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aria-label="Page 2" aria-current="page">2 </a> </li> <li> <a href="/search/?searchtype=author&query=Kono%2C+J&start=100" class="pagination-link " aria-label="Page 3" aria-current="page">3 </a> </li> </ul> </nav> <ol class="breathe-horizontal" start="1"> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2410.21171">arXiv:2410.21171</a> <span> [<a href="https://arxiv.org/pdf/2410.21171">pdf</a>, <a href="https://arxiv.org/format/2410.21171">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> </div> <p class="title is-5 mathjax"> Terahertz chiral photonic-crystal cavities with broken time-reversal symmetry </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Tay%2C+F">Fuyang Tay</a>, <a href="/search/cond-mat?searchtype=author&query=Sanders%2C+S">Stephen Sanders</a>, <a href="/search/cond-mat?searchtype=author&query=Baydin%2C+A">Andrey Baydin</a>, <a href="/search/cond-mat?searchtype=author&query=Song%2C+Z">Zhigang Song</a>, <a href="/search/cond-mat?searchtype=author&query=Welakuh%2C+D+M">Davis M. Welakuh</a>, <a href="/search/cond-mat?searchtype=author&query=Alabastri%2C+A">Alessandro Alabastri</a>, <a href="/search/cond-mat?searchtype=author&query=Rokaj%2C+V">Vasil Rokaj</a>, <a href="/search/cond-mat?searchtype=author&query=Dag%2C+C+B">Ceren B. Dag</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2410.21171v1-abstract-short" style="display: inline;"> Strong coupling between matter and vacuum electromagnetic fields in a cavity can induce novel quantum phases in thermal equilibrium via symmetry breaking. Particularly, coupling with circularly polarized fields can break time-reversal symmetry, leading to topological modifications in the band structure. Therefore, chiral optical cavities that host chiral vacuum fields are being sought, especially… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2410.21171v1-abstract-full').style.display = 'inline'; document.getElementById('2410.21171v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2410.21171v1-abstract-full" style="display: none;"> Strong coupling between matter and vacuum electromagnetic fields in a cavity can induce novel quantum phases in thermal equilibrium via symmetry breaking. Particularly, coupling with circularly polarized fields can break time-reversal symmetry, leading to topological modifications in the band structure. Therefore, chiral optical cavities that host chiral vacuum fields are being sought, especially in the terahertz (THz) frequency range, where various large-oscillator-strength resonances exist. Here, we present a novel approach to achieving THz chiral photonic-crystal cavities (PCCs) with high-quality factors (>400) using a magnetoplasma in a lightly doped semiconductor. Numerical simulations of an optimized structure based on InSb in a small perpendicular magnetic field (~0.2 T) show chiral cavity resonances with near-perfect ellipticity at the surfaces of the central dielectric layer, where one can place atomically thin materials like monolayer graphene. We theoretically estimate an energy gap on the order of 1 meV in graphene when coupled to our proposed chiral cavity, which is potentially measurable in experiments. These THz chiral PCCs offer a promising platform for exploring new phases in cavity-dressed condensed matter with broken time-reversal symmetry. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2410.21171v1-abstract-full').style.display = 'none'; document.getElementById('2410.21171v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 28 October, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2024. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">30 pages, 11 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2410.06147">arXiv:2410.06147</a> <span> [<a href="https://arxiv.org/pdf/2410.06147">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1038/s41467-024-53722-3">10.1038/s41467-024-53722-3 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Persistent flat band splitting and strong selective band renormalization in a kagome magnet thin film </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Ren%2C+Z">Zheng Ren</a>, <a href="/search/cond-mat?searchtype=author&query=Huang%2C+J">Jianwei Huang</a>, <a href="/search/cond-mat?searchtype=author&query=Tan%2C+H">Hengxin Tan</a>, <a href="/search/cond-mat?searchtype=author&query=Biswas%2C+A">Ananya Biswas</a>, <a href="/search/cond-mat?searchtype=author&query=Pulkkinen%2C+A">Aki Pulkkinen</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+Y">Yichen Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Xie%2C+Y">Yaofeng Xie</a>, <a href="/search/cond-mat?searchtype=author&query=Yue%2C+Z">Ziqin Yue</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+L">Lei Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Xie%2C+F">Fang Xie</a>, <a href="/search/cond-mat?searchtype=author&query=Allen%2C+K">Kevin Allen</a>, <a href="/search/cond-mat?searchtype=author&query=Wu%2C+H">Han Wu</a>, <a href="/search/cond-mat?searchtype=author&query=Ren%2C+Q">Qirui Ren</a>, <a href="/search/cond-mat?searchtype=author&query=Rajapitamahuni%2C+A">Anil Rajapitamahuni</a>, <a href="/search/cond-mat?searchtype=author&query=Kundu%2C+A">Asish Kundu</a>, <a href="/search/cond-mat?searchtype=author&query=Vescovo%2C+E">Elio Vescovo</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Morosan%2C+E">Emilia Morosan</a>, <a href="/search/cond-mat?searchtype=author&query=Dai%2C+P">Pengcheng Dai</a>, <a href="/search/cond-mat?searchtype=author&query=Zhu%2C+J">Jian-Xin Zhu</a>, <a href="/search/cond-mat?searchtype=author&query=Si%2C+Q">Qimiao Si</a>, <a href="/search/cond-mat?searchtype=author&query=Min%C3%A1r%2C+J">J谩n Min谩r</a>, <a href="/search/cond-mat?searchtype=author&query=Yan%2C+B">Binghai Yan</a>, <a href="/search/cond-mat?searchtype=author&query=Yi%2C+M">Ming Yi</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2410.06147v1-abstract-short" style="display: inline;"> Magnetic kagome materials provide a fascinating playground for exploring the interplay of magnetism, correlation and topology. Many magnetic kagome systems have been reported including the binary FemXn (X=Sn, Ge; m:n = 3:1, 3:2, 1:1) family and the rare earth RMn6Sn6 (R = rare earth) family, where their kagome flat bands are calculated to be near the Fermi level in the paramagnetic phase. While pa… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2410.06147v1-abstract-full').style.display = 'inline'; document.getElementById('2410.06147v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2410.06147v1-abstract-full" style="display: none;"> Magnetic kagome materials provide a fascinating playground for exploring the interplay of magnetism, correlation and topology. Many magnetic kagome systems have been reported including the binary FemXn (X=Sn, Ge; m:n = 3:1, 3:2, 1:1) family and the rare earth RMn6Sn6 (R = rare earth) family, where their kagome flat bands are calculated to be near the Fermi level in the paramagnetic phase. While partially filling a kagome flat band is predicted to give rise to a Stoner-type ferromagnetism, experimental visualization of the magnetic splitting across the ordering temperature has not been reported for any of these systems due to the high ordering temperatures, hence leaving the nature of magnetism in kagome magnets an open question. Here, we probe the electronic structure with angle-resolved photoemission spectroscopy in a kagome magnet thin film FeSn synthesized using molecular beam epitaxy. We identify the exchange-split kagome flat bands, whose splitting persists above the magnetic ordering temperature, indicative of a local moment picture. Such local moments in the presence of the topological flat band are consistent with the compact molecular orbitals predicted in theory. We further observe a large spin-orbital selective band renormalization in the Fe d_xy+d_(x^2-y^2 ) spin majority channel reminiscent of the orbital selective correlation effects in the iron-based superconductors. Our discovery of the coexistence of local moments with topological flat bands in a kagome system echoes similar findings in magic-angle twisted bilayer graphene, and provides a basis for theoretical effort towards modeling correlation effects in magnetic flat band systems. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2410.06147v1-abstract-full').style.display = 'none'; document.getElementById('2410.06147v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 8 October, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2024. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Nature Communications 15, 9376 (2024) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2409.17339">arXiv:2409.17339</a> <span> [<a href="https://arxiv.org/pdf/2409.17339">pdf</a>, <a href="https://arxiv.org/format/2409.17339">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Other Condensed Matter">cond-mat.other</span> </div> </div> <p class="title is-5 mathjax"> Zeeman polaritons as a platform for probing Dicke physics in condensed matter </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Kritzell%2C+T+E">T. Elijah Kritzell</a>, <a href="/search/cond-mat?searchtype=author&query=Doumani%2C+J">Jacques Doumani</a>, <a href="/search/cond-mat?searchtype=author&query=Asano%2C+T">Tobias Asano</a>, <a href="/search/cond-mat?searchtype=author&query=Yamada%2C+S">Sota Yamada</a>, <a href="/search/cond-mat?searchtype=author&query=Tay%2C+F">Fuyang Tay</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+H">Hongjing Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Yan%2C+H">Han Yan</a>, <a href="/search/cond-mat?searchtype=author&query=Katayama%2C+I">Ikufumi Katayama</a>, <a href="/search/cond-mat?searchtype=author&query=Takeda%2C+J">Jun Takeda</a>, <a href="/search/cond-mat?searchtype=author&query=Nevidomskyy%2C+A">Andriy Nevidomskyy</a>, <a href="/search/cond-mat?searchtype=author&query=Nojiri%2C+H">Hiroyuki Nojiri</a>, <a href="/search/cond-mat?searchtype=author&query=Bamba%2C+M">Motoaki Bamba</a>, <a href="/search/cond-mat?searchtype=author&query=Baydin%2C+A">Andrey Baydin</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2409.17339v1-abstract-short" style="display: inline;"> The interaction of an ensemble of two-level atoms and a quantized electromagnetic field, described by the Dicke Hamiltonian, is an extensively studied problem in quantum optics. However, experimental efforts to explore similar physics in condensed matter typically employ bosonic matter modes (e.g., phonons, magnons, and plasmons) that are describable as simple harmonic oscillators, i.e., an infini… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2409.17339v1-abstract-full').style.display = 'inline'; document.getElementById('2409.17339v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2409.17339v1-abstract-full" style="display: none;"> The interaction of an ensemble of two-level atoms and a quantized electromagnetic field, described by the Dicke Hamiltonian, is an extensively studied problem in quantum optics. However, experimental efforts to explore similar physics in condensed matter typically employ bosonic matter modes (e.g., phonons, magnons, and plasmons) that are describable as simple harmonic oscillators, i.e., an infinite ladder of equally spaced energy levels. Here, we examine ultrastrong coupling between a coherent light mode and an ensemble of paramagnetic spins, a finite-multilevel system, in Gd$_3$Ga$_5$O$_{12}$. The electron paramagnetic resonance of Gd$^{3+}$ ions is tuned by a magnetic field into resonance with a Fabry--P茅rot cavity mode, resulting in the formation of spin--photon hybrid states, or Zeeman polaritons. We observe that the light--matter coupling strength, measured through the vacuum Rabi splitting, decreases with increasing temperature, which can be explained by the temperature-dependent population difference between the lower and higher-energy states, a trait of a finite-level system. This finding demonstrates that a spin--boson system is more compatible with the Dicke model and has advantages over boson--boson systems for pursuing experimental realizations of phenomena predicted for ultrastrongly coupled light--matter hybrids. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2409.17339v1-abstract-full').style.display = 'none'; document.getElementById('2409.17339v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 25 September, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2024. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2409.12423">arXiv:2409.12423</a> <span> [<a href="https://arxiv.org/pdf/2409.12423">pdf</a>, <a href="https://arxiv.org/format/2409.12423">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> </div> <p class="title is-5 mathjax"> Topological Surface State Evolution in Bi$_2$Se$_3$ via Surface Etching </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Yue%2C+Z">Ziqin Yue</a>, <a href="/search/cond-mat?searchtype=author&query=Huang%2C+J">Jianwei Huang</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%2C+R">Ruohan Wang</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+J">Jia-Wan Li</a>, <a href="/search/cond-mat?searchtype=author&query=Rong%2C+H">Hongtao Rong</a>, <a href="/search/cond-mat?searchtype=author&query=Guo%2C+Y">Yucheng Guo</a>, <a href="/search/cond-mat?searchtype=author&query=Wu%2C+H">Han Wu</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+Y">Yichen Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Zhou%2C+X">Xingjiang Zhou</a>, <a href="/search/cond-mat?searchtype=author&query=Hou%2C+Y">Yusheng Hou</a>, <a href="/search/cond-mat?searchtype=author&query=Wu%2C+R">Ruqian Wu</a>, <a href="/search/cond-mat?searchtype=author&query=Yi%2C+M">Ming Yi</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2409.12423v1-abstract-short" style="display: inline;"> Topological insulators are materials with an insulating bulk interior while maintaining gapless boundary states against back scattering. Bi$_2$Se$_3$ is a prototypical topological insulator with a Dirac-cone surface state around $螕$. Here, we present a controlled methodology to gradually remove Se atoms from the surface Se-Bi-Se-Bi-Se quintuple layers, eventually forming bilayer-Bi on top of the q… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2409.12423v1-abstract-full').style.display = 'inline'; document.getElementById('2409.12423v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2409.12423v1-abstract-full" style="display: none;"> Topological insulators are materials with an insulating bulk interior while maintaining gapless boundary states against back scattering. Bi$_2$Se$_3$ is a prototypical topological insulator with a Dirac-cone surface state around $螕$. Here, we present a controlled methodology to gradually remove Se atoms from the surface Se-Bi-Se-Bi-Se quintuple layers, eventually forming bilayer-Bi on top of the quintuple bulk. Our method allows us to track the topological surface state and confirm its robustness throughout the surface modification. Importantly, we report a relocation of the topological Dirac cone in both real space and momentum space, as the top surface layer transitions from quintuple Se-Bi-Se-Bi-Se to bilayer-Bi. Additionally, charge transfer among different surface layers is identified. Our study provides a precise method to manipulate surface configurations, allowing for the fine-tuning of the topological surface states in Bi$_2$Se$_3$, which represents a significant advancement towards nano-engineering of topological states. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2409.12423v1-abstract-full').style.display = 'none'; document.getElementById('2409.12423v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 18 September, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2024. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">21 pages, 5 figures, accepted for publication in Nano Letters</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2409.04505">arXiv:2409.04505</a> <span> [<a href="https://arxiv.org/pdf/2409.04505">pdf</a>, <a href="https://arxiv.org/format/2409.04505">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> </div> <p class="title is-5 mathjax"> Cavity-mediated superthermal phonon correlations in the ultrastrong coupling regime </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Kim%2C+D">Dasom Kim</a>, <a href="/search/cond-mat?searchtype=author&query=Hou%2C+J">Jin Hou</a>, <a href="/search/cond-mat?searchtype=author&query=Lee%2C+G">Geon Lee</a>, <a href="/search/cond-mat?searchtype=author&query=Agrawal%2C+A">Ayush Agrawal</a>, <a href="/search/cond-mat?searchtype=author&query=Kim%2C+S">Sunghwan Kim</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+H">Hao Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Bao%2C+D">Di Bao</a>, <a href="/search/cond-mat?searchtype=author&query=Baydin%2C+A">Andrey Baydin</a>, <a href="/search/cond-mat?searchtype=author&query=Wu%2C+W">Wenjing Wu</a>, <a href="/search/cond-mat?searchtype=author&query=Tay%2C+F">Fuyang Tay</a>, <a href="/search/cond-mat?searchtype=author&query=Huang%2C+S">Shengxi Huang</a>, <a href="/search/cond-mat?searchtype=author&query=Chia%2C+E+E+M">Elbert E. M. Chia</a>, <a href="/search/cond-mat?searchtype=author&query=Kim%2C+D">Dai-Sik Kim</a>, <a href="/search/cond-mat?searchtype=author&query=Seo%2C+M">Minah Seo</a>, <a href="/search/cond-mat?searchtype=author&query=Mohite%2C+A+D">Aditya D. Mohite</a>, <a href="/search/cond-mat?searchtype=author&query=Hagenm%C3%BCller%2C+D">David Hagenm眉ller</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2409.04505v1-abstract-short" style="display: inline;"> Phonons, or vibrational quanta, are behind some of the most fundamental physical phenomena in solids, including superconductivity, Raman processes, and broken-symmetry phases. It is therefore of fundamental importance to find ways to harness phonons for controlling these phenomena and developing novel quantum technologies. However, the majority of current phonon control techniques rely on the use… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2409.04505v1-abstract-full').style.display = 'inline'; document.getElementById('2409.04505v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2409.04505v1-abstract-full" style="display: none;"> Phonons, or vibrational quanta, are behind some of the most fundamental physical phenomena in solids, including superconductivity, Raman processes, and broken-symmetry phases. It is therefore of fundamental importance to find ways to harness phonons for controlling these phenomena and developing novel quantum technologies. However, the majority of current phonon control techniques rely on the use of intense external driving fields or strong anharmonicities, which restricts their range of applications. Here, we present a scheme for controlling the intensity fluctuations in phonon emission at room temperature based on multimode ultrastrong light--matter coupling. The multimode ultrastrong coupling regime is achieved by coupling two optical phonon modes in lead halide perovskites to an array of nanoslots, which operates as a single-mode cavity. The extremely small mode volume of the nanoslots enables unprecedented coupling strengths in a cavity phonon-polariton system. In the far-detuned, low-cavity-frequency regime, we demonstrate that the nanoslot resonator mediates an effective coupling between the phonon modes, resulting in superthermal phonon bunching in thermal equilibrium, both within the same mode and between different modes. Experimental results are in good agreement with a multimode Hopfield model. Our work paves the way for the tailoring of phonons to modify charge and energy transport in perovskite materials, with potential applications in light-collecting or emitting devices. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2409.04505v1-abstract-full').style.display = 'none'; document.getElementById('2409.04505v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 6 September, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2024. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2407.04514">arXiv:2407.04514</a> <span> [<a href="https://arxiv.org/pdf/2407.04514">pdf</a>, <a href="https://arxiv.org/format/2407.04514">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> </div> <p class="title is-5 mathjax"> Giant Second Harmonic Generation from Wafer-Scale Aligned Chiral Carbon Nanotubes </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Xu%2C+R">Rui Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Doumani%2C+J">Jacques Doumani</a>, <a href="/search/cond-mat?searchtype=author&query=Labuntsov%2C+V">Viktor Labuntsov</a>, <a href="/search/cond-mat?searchtype=author&query=Hong%2C+N">Nina Hong</a>, <a href="/search/cond-mat?searchtype=author&query=Samaha%2C+A">Anna-Christina Samaha</a>, <a href="/search/cond-mat?searchtype=author&query=Tu%2C+W">Weiran Tu</a>, <a href="/search/cond-mat?searchtype=author&query=Tay%2C+F">Fuyang Tay</a>, <a href="/search/cond-mat?searchtype=author&query=Blackert%2C+E">Elizabeth Blackert</a>, <a href="/search/cond-mat?searchtype=author&query=Luo%2C+J">Jiaming Luo</a>, <a href="/search/cond-mat?searchtype=author&query=Tahchi%2C+M+E">Mario El Tahchi</a>, <a href="/search/cond-mat?searchtype=author&query=Gao%2C+W">Weilu Gao</a>, <a href="/search/cond-mat?searchtype=author&query=Lou%2C+J">Jun Lou</a>, <a href="/search/cond-mat?searchtype=author&query=Yomogida%2C+Y">Yohei Yomogida</a>, <a href="/search/cond-mat?searchtype=author&query=Yanagi%2C+K">Kazuhiro Yanagi</a>, <a href="/search/cond-mat?searchtype=author&query=Saito%2C+R">Riichiro Saito</a>, <a href="/search/cond-mat?searchtype=author&query=Perebeinos%2C+V">Vasili Perebeinos</a>, <a href="/search/cond-mat?searchtype=author&query=Baydin%2C+A">Andrey Baydin</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Zhu%2C+H">Hanyu Zhu</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2407.04514v1-abstract-short" style="display: inline;"> Chiral carbon nanotubes (CNTs) are direct-gap semiconductors with optical properties governed by one-dimensional excitons with enormous oscillator strengths. Each species of chiral CNTs has an enantiomeric pair of left- and right-handed CNTs with nearly identical properties, but enantiomer-dependent phenomena can emerge, especially in nonlinear optical processes. Theoretical studies have predicted… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2407.04514v1-abstract-full').style.display = 'inline'; document.getElementById('2407.04514v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2407.04514v1-abstract-full" style="display: none;"> Chiral carbon nanotubes (CNTs) are direct-gap semiconductors with optical properties governed by one-dimensional excitons with enormous oscillator strengths. Each species of chiral CNTs has an enantiomeric pair of left- and right-handed CNTs with nearly identical properties, but enantiomer-dependent phenomena can emerge, especially in nonlinear optical processes. Theoretical studies have predicted strong second-order nonlinearities for chiral CNTs, but there has been no experimental verification due to the lack of macroscopically ordered assemblies of single-enantiomer chiral CNTs. Here for the first time, we report the synthesis of centimeter-scale films of densely packed and aligned single-enantiomer chiral CNTs that exhibit micro-fabrication compatibility. We observe giant second harmonic generation (SHG) emission from the chiral CNT film, which originates from the intrinsic chirality and inversion symmetry breaking of the atomic structure of chiral CNTs. The observed value of the dominant element of the second-order nonlinear optical susceptibility tensor reaches $1.5\times 10^{3}$ pm/V at a pump wavelength of 1030 nm, corresponding to the lowest-energy excitonic resonance. Our calculations based on many-body theory correctly estimate the spectrum and magnitude of such excitonically enhanced optical nonlinearity. These results are promising for developing scalable chiral-CNT electronics, nonlinear photonics and photonic quantum computing. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2407.04514v1-abstract-full').style.display = 'none'; document.getElementById('2407.04514v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 5 July, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2024. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2406.05293">arXiv:2406.05293</a> <span> [<a href="https://arxiv.org/pdf/2406.05293">pdf</a>, <a href="https://arxiv.org/format/2406.05293">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Strongly Correlated Electrons">cond-mat.str-el</span> </div> </div> <p class="title is-5 mathjax"> Ubiquitous Flat Bands in a Cr-based Kagome Superconductor </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Guo%2C+Y">Yucheng Guo</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%2C+Z">Zehao Wang</a>, <a href="/search/cond-mat?searchtype=author&query=Xie%2C+F">Fang Xie</a>, <a href="/search/cond-mat?searchtype=author&query=Huang%2C+Y">Yuefei Huang</a>, <a href="/search/cond-mat?searchtype=author&query=Gao%2C+B">Bin Gao</a>, <a href="/search/cond-mat?searchtype=author&query=Oh%2C+J+S">Ji Seop Oh</a>, <a href="/search/cond-mat?searchtype=author&query=Wu%2C+H">Han Wu</a>, <a href="/search/cond-mat?searchtype=author&query=Liu%2C+Z">Zhaoyu Liu</a>, <a href="/search/cond-mat?searchtype=author&query=Ren%2C+Z">Zheng Ren</a>, <a href="/search/cond-mat?searchtype=author&query=Fang%2C+Y">Yuan Fang</a>, <a href="/search/cond-mat?searchtype=author&query=Biswas%2C+A">Ananya Biswas</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+Y">Yichen Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Yue%2C+Z">Ziqin Yue</a>, <a href="/search/cond-mat?searchtype=author&query=Hu%2C+C">Cheng Hu</a>, <a href="/search/cond-mat?searchtype=author&query=Jozwiak%2C+C">Chris Jozwiak</a>, <a href="/search/cond-mat?searchtype=author&query=Bostwick%2C+A">Aaron Bostwick</a>, <a href="/search/cond-mat?searchtype=author&query=Rotenberg%2C+E">Eli Rotenberg</a>, <a href="/search/cond-mat?searchtype=author&query=Hashimoto%2C+M">Makoto Hashimoto</a>, <a href="/search/cond-mat?searchtype=author&query=Lu%2C+D">Donghui Lu</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Chu%2C+J">Jiun-Haw Chu</a>, <a href="/search/cond-mat?searchtype=author&query=Yakobson%2C+B+I">Boris I Yakobson</a>, <a href="/search/cond-mat?searchtype=author&query=Birgeneau%2C+R+J">Robert J Birgeneau</a>, <a href="/search/cond-mat?searchtype=author&query=Si%2C+Q">Qimiao Si</a>, <a href="/search/cond-mat?searchtype=author&query=Dai%2C+P">Pengcheng Dai</a> , et al. (1 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2406.05293v2-abstract-short" style="display: inline;"> In the quest for novel quantum states driven by topology and correlation, kagome lattice materials have garnered significant interest due to their distinctive electronic band structures, featuring flat bands (FBs) arising from the quantum destructive interference of the electronic wave function. The tuning of the FBs to the chemical potential would lead to the possibility of liberating electronic… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2406.05293v2-abstract-full').style.display = 'inline'; document.getElementById('2406.05293v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2406.05293v2-abstract-full" style="display: none;"> In the quest for novel quantum states driven by topology and correlation, kagome lattice materials have garnered significant interest due to their distinctive electronic band structures, featuring flat bands (FBs) arising from the quantum destructive interference of the electronic wave function. The tuning of the FBs to the chemical potential would lead to the possibility of liberating electronic instabilities that lead to emergent electronic orders. Despite extensive studies, direct evidence of FBs tuned to the chemical potential and their participation in emergent electronic orders have been lacking in bulk quantum materials. Here using a combination of Angle-Resolved Photoemission Spectroscopy (ARPES) and Density Functional Theory (DFT), we reveal that the low-energy electronic structure of the recently discovered Cr-based kagome metal superconductor CsCr3Sb5 is dominated by a pervasive FB in close proximity to, and below the Fermi level. A comparative analysis with orbital-projected DFT and polarization dependence measurement uncovers that an orbital-selective renormalization mechanism is needed to reconcile the discrepancy with the DFT calculations, which predict the FB to appear 200 meV above the Fermi level. Furthermore, we observe the FB to shift away from the Fermi level by 20 meV in the low-temperature density wave-ordered phase, highlighting the role of the FB in the emergent electronic order. Our results reveal CsCr3Sb5 to stand out as a promising platform for further exploration into the effects of FBs near the Fermi level on kagome lattices, and their role in emergent orders in bulk quantum materials. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2406.05293v2-abstract-full').style.display = 'none'; document.getElementById('2406.05293v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 12 June, 2024; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 7 June, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2024. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2402.11357">arXiv:2402.11357</a> <span> [<a href="https://arxiv.org/pdf/2402.11357">pdf</a>, <a href="https://arxiv.org/format/2402.11357">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> </div> <p class="title is-5 mathjax"> Graphene Terahertz Devices for Sensing and Communication </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Samaha%2C+A">Anna-Christina Samaha</a>, <a href="/search/cond-mat?searchtype=author&query=Doumani%2C+J">Jacques Doumani</a>, <a href="/search/cond-mat?searchtype=author&query=Kritzell%2C+T+E">T. Elijah Kritzell</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+H">Hongjing Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Baydin%2C+A">Andrey Baydin</a>, <a href="/search/cond-mat?searchtype=author&query=Ajayan%2C+P+M">Pulickel M. Ajayan</a>, <a href="/search/cond-mat?searchtype=author&query=Tahchi%2C+M+E">Mario El Tahchi</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2402.11357v2-abstract-short" style="display: inline;"> Graphene-based terahertz (THz) devices have emerged as promising platforms for a variety of applications, leveraging graphene's unique optoelectronic properties. This review explores recent advancements in utilizing graphene in THz technology, focusing on two main aspects: THz molecular sensing and THz wave modulation. In molecular sensing, the environment-sensitive THz transmission and emission p… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2402.11357v2-abstract-full').style.display = 'inline'; document.getElementById('2402.11357v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2402.11357v2-abstract-full" style="display: none;"> Graphene-based terahertz (THz) devices have emerged as promising platforms for a variety of applications, leveraging graphene's unique optoelectronic properties. This review explores recent advancements in utilizing graphene in THz technology, focusing on two main aspects: THz molecular sensing and THz wave modulation. In molecular sensing, the environment-sensitive THz transmission and emission properties of graphene are utilized for enabling molecular adsorption detection and biomolecular sensing. This capability holds significant potential, from the detection of pesticides to DNA at high sensitivity and selectivity. In THz wave modulation, crucial for next-generation wireless communication systems, graphene demonstrates remarkable potential in absorption modulation when gated. Novel device structures, spectroscopic systems, and metasurface architectures have enabled enhanced absorption and wave modulation. Furthermore, techniques such as spatial phase modulation and polarization manipulation have been explored. From sensing to communication, graphene-based THz devices present a wide array of opportunities for future research and development. Finally, advancements in sensing techniques not only enhance biomolecular analysis but also contribute to optimizing graphene's properties for communication by enabling efficient modulation of electromagnetic waves. Conversely, developments in communication strategies inform and enhance sensing capabilities, establishing a mutually beneficial relationship. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2402.11357v2-abstract-full').style.display = 'none'; document.getElementById('2402.11357v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 25 May, 2024; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 17 February, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2024. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2401.01873">arXiv:2401.01873</a> <span> [<a href="https://arxiv.org/pdf/2401.01873">pdf</a>, <a href="https://arxiv.org/format/2401.01873">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> </div> <p class="title is-5 mathjax"> Observation of the Magnonic Dicke Superradiant Phase Transition </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Kim%2C+D">Dasom Kim</a>, <a href="/search/cond-mat?searchtype=author&query=Dasgupta%2C+S">Sohail Dasgupta</a>, <a href="/search/cond-mat?searchtype=author&query=Ma%2C+X">Xiaoxuan Ma</a>, <a href="/search/cond-mat?searchtype=author&query=Park%2C+J">Joong-Mok Park</a>, <a href="/search/cond-mat?searchtype=author&query=Wei%2C+H">Hao-Tian Wei</a>, <a href="/search/cond-mat?searchtype=author&query=Luo%2C+L">Liang Luo</a>, <a href="/search/cond-mat?searchtype=author&query=Doumani%2C+J">Jacques Doumani</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+X">Xinwei Li</a>, <a href="/search/cond-mat?searchtype=author&query=Yang%2C+W">Wanting Yang</a>, <a href="/search/cond-mat?searchtype=author&query=Cheng%2C+D">Di Cheng</a>, <a href="/search/cond-mat?searchtype=author&query=Kim%2C+R+H+J">Richard H. J. Kim</a>, <a href="/search/cond-mat?searchtype=author&query=Everitt%2C+H+O">Henry O. Everitt</a>, <a href="/search/cond-mat?searchtype=author&query=Kimura%2C+S">Shojiro Kimura</a>, <a href="/search/cond-mat?searchtype=author&query=Nojiri%2C+H">Hiroyuki Nojiri</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%2C+J">Jigang Wang</a>, <a href="/search/cond-mat?searchtype=author&query=Cao%2C+S">Shixun Cao</a>, <a href="/search/cond-mat?searchtype=author&query=Bamba%2C+M">Motoaki Bamba</a>, <a href="/search/cond-mat?searchtype=author&query=Hazzard%2C+K+R+A">Kaden R. A. Hazzard</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2401.01873v1-abstract-short" style="display: inline;"> Two-level atoms coupled with single-mode cavity photons are predicted to exhibit a quantum phase transition when the coupling strength exceeds a critical value, entering a phase in which atomic polarization and photonic field are finite even at zero temperature and without external driving. However, this phenomenon, the superradiant phase transition (SRPT), is forbidden by a no-go theorem due to t… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2401.01873v1-abstract-full').style.display = 'inline'; document.getElementById('2401.01873v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2401.01873v1-abstract-full" style="display: none;"> Two-level atoms coupled with single-mode cavity photons are predicted to exhibit a quantum phase transition when the coupling strength exceeds a critical value, entering a phase in which atomic polarization and photonic field are finite even at zero temperature and without external driving. However, this phenomenon, the superradiant phase transition (SRPT), is forbidden by a no-go theorem due to the existence of the diamagnetic term in the Hamiltonian. Here, we present spectroscopic evidence for a magnonic SRPT in ErFeO$_3$, where the role of the photonic mode (two-level atoms) in the photonic SRPT is played by an Fe$^{3+}$ magnon mode (Er$^{3+}$ spins). The absence of the diamagnetic term in the Fe$^{3+}$-Er$^{3+}$ exchange coupling ensures that the no-go theorem does not apply. Terahertz and gigahertz magnetospectroscopy experiments revealed the signatures of the SRPT -- a kink and a softening, respectively, of two spin-magnon hybridized modes at the critical point. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2401.01873v1-abstract-full').style.display = 'none'; document.getElementById('2401.01873v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 3 January, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2024. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2312.11732">arXiv:2312.11732</a> <span> [<a href="https://arxiv.org/pdf/2312.11732">pdf</a>, <a href="https://arxiv.org/format/2312.11732">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Strongly Correlated Electrons">cond-mat.str-el</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevB.109.045416">10.1103/PhysRevB.109.045416 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Two-Step Electronic Response to Magnetic Ordering in a van der Waals Ferromagnet </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Wu%2C+H">Han Wu</a>, <a href="/search/cond-mat?searchtype=author&query=Zhu%2C+J">Jian-Xin Zhu</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+L">Lebing Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Butcher%2C+M+W">Matthew W Butcher</a>, <a href="/search/cond-mat?searchtype=author&query=Yue%2C+Z">Ziqin Yue</a>, <a href="/search/cond-mat?searchtype=author&query=Yuan%2C+D">Dongsheng Yuan</a>, <a href="/search/cond-mat?searchtype=author&query=He%2C+Y">Yu He</a>, <a href="/search/cond-mat?searchtype=author&query=Oh%2C+J+S">Ji Seop Oh</a>, <a href="/search/cond-mat?searchtype=author&query=Huang%2C+J">Jianwei Huang</a>, <a href="/search/cond-mat?searchtype=author&query=Wu%2C+S">Shan Wu</a>, <a href="/search/cond-mat?searchtype=author&query=Gong%2C+C">Cheng Gong</a>, <a href="/search/cond-mat?searchtype=author&query=Guo%2C+Y">Yucheng Guo</a>, <a href="/search/cond-mat?searchtype=author&query=Mo%2C+S">Sung-Kwan Mo</a>, <a href="/search/cond-mat?searchtype=author&query=Denlinger%2C+J+D">Jonathan D. Denlinger</a>, <a href="/search/cond-mat?searchtype=author&query=Lu%2C+D">Donghui Lu</a>, <a href="/search/cond-mat?searchtype=author&query=Hashimoto%2C+M">Makoto Hashimoto</a>, <a href="/search/cond-mat?searchtype=author&query=Stone%2C+M+B">Matthew B. Stone</a>, <a href="/search/cond-mat?searchtype=author&query=Kolesnikov%2C+A+I">Alexander I. Kolesnikov</a>, <a href="/search/cond-mat?searchtype=author&query=Chi%2C+S">Songxue Chi</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Nevidomskyy%2C+A+H">Andriy H. Nevidomskyy</a>, <a href="/search/cond-mat?searchtype=author&query=Birgeneau%2C+R+J">Robert J. Birgeneau</a>, <a href="/search/cond-mat?searchtype=author&query=Dai%2C+P">Pengcheng Dai</a>, <a href="/search/cond-mat?searchtype=author&query=Yi%2C+M">Ming Yi</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2312.11732v2-abstract-short" style="display: inline;"> The two-dimensional (2D) material Cr$_2$Ge$_2$Te$_6$ is a member of the class of insulating van der Waals magnets. Here, using high resolution angle-resolved photoemission spectroscopy in a detailed temperature dependence study, we identify a clear response of the electronic structure to a dimensional crossover in the form of two distinct temperature scales marking onsets of modifications in the e… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2312.11732v2-abstract-full').style.display = 'inline'; document.getElementById('2312.11732v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2312.11732v2-abstract-full" style="display: none;"> The two-dimensional (2D) material Cr$_2$Ge$_2$Te$_6$ is a member of the class of insulating van der Waals magnets. Here, using high resolution angle-resolved photoemission spectroscopy in a detailed temperature dependence study, we identify a clear response of the electronic structure to a dimensional crossover in the form of two distinct temperature scales marking onsets of modifications in the electronic structure. Specifically, we observe Te $p$-orbital-dominated bands to undergo changes at the Curie transition temperature T$_C$ while the Cr $d$-orbital-dominated bands begin evolving at a higher temperature scale. Combined with neutron scattering, density functional theory calculations, and Monte Carlo simulations, we find that the electronic system can be consistently understood to respond sequentially to the distinct temperatures at which in-plane and out-of-plane spin correlations exceed a characteristic length scale. Our findings reveal the sensitivity of the orbital-selective electronic structure for probing the dynamical evolution of local moment correlations in vdW insulating magnets. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2312.11732v2-abstract-full').style.display = 'none'; document.getElementById('2312.11732v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 20 December, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 18 December, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2023. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">PRB, in press</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Physical Review B 109, 045416 (2024) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2312.00984">arXiv:2312.00984</a> <span> [<a href="https://arxiv.org/pdf/2312.00984">pdf</a>, <a href="https://arxiv.org/format/2312.00984">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> </div> <p class="title is-5 mathjax"> Macroscopically Self-Aligned and Chiralized Carbon Nanotubes: From Filtration to Innovation </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Doumani%2C+J">Jacques Doumani</a>, <a href="/search/cond-mat?searchtype=author&query=Zahn%2C+K">Keshav Zahn</a>, <a href="/search/cond-mat?searchtype=author&query=Yu%2C+S">Shengjie Yu</a>, <a href="/search/cond-mat?searchtype=author&query=Barrios%2C+G+R">Gustavo Rodriguez Barrios</a>, <a href="/search/cond-mat?searchtype=author&query=Sasmal%2C+S">Somesh Sasmal</a>, <a href="/search/cond-mat?searchtype=author&query=Kikuchi%2C+R">Rikuta Kikuchi</a>, <a href="/search/cond-mat?searchtype=author&query=Kritzell%2C+T+E">T. Elijah Kritzell</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+H">Hongjing Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Baydin%2C+A">Andrey Baydin</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2312.00984v1-abstract-short" style="display: inline;"> Because of their natural one-dimensional (1D) structure combined with intricate chiral variations, carbon nanotubes (CNTs) exhibit various exceptional physical properties, such as ultrahigh electrical and thermal conductivity, exceptional mechanical strength, and chirality-dependent metallicity. These properties make CNTs highly promising for diverse applications, including field-effect transistor… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2312.00984v1-abstract-full').style.display = 'inline'; document.getElementById('2312.00984v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2312.00984v1-abstract-full" style="display: none;"> Because of their natural one-dimensional (1D) structure combined with intricate chiral variations, carbon nanotubes (CNTs) exhibit various exceptional physical properties, such as ultrahigh electrical and thermal conductivity, exceptional mechanical strength, and chirality-dependent metallicity. These properties make CNTs highly promising for diverse applications, including field-effect transistors, sensors, photodetectors, and thermoelectric devices. While CNTs excel individually at the nanoscale, their 1D and chiral nature can be lost on a macroscopic scale when they are randomly assembled. Therefore, the alignment and organization of CNTs in macroscopic structures is crucial for harnessing their full potential. In this review, we explore recent advancements in understanding CNT alignment mechanisms, improving CNT aligning methods, and demonstrating macroscopically 1D properties of ordered CNT assemblies. We also focus on a newly discovered class of CNT architectures, combining CNT alignment and twisting mechanisms to create artificial radial and chiral CNT films at wafer scales. Finally, we summarize recent developments related to aligned and chiral CNT films in optoelectronics, highlighting their unique roles in solar cells, thermal emitters, and optical modulators. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2312.00984v1-abstract-full').style.display = 'none'; document.getElementById('2312.00984v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 1 December, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2023. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2308.12427">arXiv:2308.12427</a> <span> [<a href="https://arxiv.org/pdf/2308.12427">pdf</a>, <a href="https://arxiv.org/format/2308.12427">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> </div> <p class="title is-5 mathjax"> Multimode Ultrastrong Coupling in Three-Dimensional Photonic-Crystal Cavities </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Tay%2C+F">Fuyang Tay</a>, <a href="/search/cond-mat?searchtype=author&query=Mojibpour%2C+A">Ali Mojibpour</a>, <a href="/search/cond-mat?searchtype=author&query=Sanders%2C+S">Stephen Sanders</a>, <a href="/search/cond-mat?searchtype=author&query=Liang%2C+S">Shuang Liang</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+H">Hongjing Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Gardner%2C+G+C">Geoff C. Gardner</a>, <a href="/search/cond-mat?searchtype=author&query=Baydin%2C+A">Andrey Baydin</a>, <a href="/search/cond-mat?searchtype=author&query=Manfra%2C+M+J">Michael J. Manfra</a>, <a href="/search/cond-mat?searchtype=author&query=Alabastri%2C+A">Alessandro Alabastri</a>, <a href="/search/cond-mat?searchtype=author&query=Hagenm%C3%BCller%2C+D">David Hagenm眉ller</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2308.12427v3-abstract-short" style="display: inline;"> Recent theoretical studies have highlighted the role of spatially varying cavity electromagnetic fields in exploring novel cavity quantum electrodynamics (cQED) phenomena, such as the potential realization of the elusive Dicke superradiant phase transition. One-dimensional photonic-crystal cavities (PCCs), widely used for studying solid-state cQED systems, have uniform spatial profiles in the late… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2308.12427v3-abstract-full').style.display = 'inline'; document.getElementById('2308.12427v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2308.12427v3-abstract-full" style="display: none;"> Recent theoretical studies have highlighted the role of spatially varying cavity electromagnetic fields in exploring novel cavity quantum electrodynamics (cQED) phenomena, such as the potential realization of the elusive Dicke superradiant phase transition. One-dimensional photonic-crystal cavities (PCCs), widely used for studying solid-state cQED systems, have uniform spatial profiles in the lateral plane. Three-dimensional (3D) PCCs, which exhibit discrete in-plane translational symmetry, overcome this limitation, but fabrication challenges have hindered the achievement of strong coupling in 3D-PCCs. Here, we report the realization of multimode ultrastrong coupling in a 3D-PCC at terahertz frequencies. The multimode coupling between the 3D-PCC's cavity modes and the cyclotron resonance of a Landau-quantized two-dimensional electron gas in GaAs is significantly influenced by the spatial profiles of the cavity modes, leading to distinct coupling scenarios depending on the probe polarization. Our experimental results are in excellent agreement with a multimode extended Hopfield model that accounts for the spatial inhomogeneity of the cavity field. Guided by the model, we discuss the possible strong ground-state correlations between different cavity modes and introduce relevant figures of merit for the multimode ultrastrong coupling regime. Our findings emphasize the importance of spatially nonuniform cavity mode profiles in probing nonintuitive quantum phenomena expected for the ground states of cQED systems in the ultrastrong coupling regime. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2308.12427v3-abstract-full').style.display = 'none'; document.getElementById('2308.12427v3-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 8 July, 2024; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 23 August, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2023. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">36 pages, 13 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2307.03154">arXiv:2307.03154</a> <span> [<a href="https://arxiv.org/pdf/2307.03154">pdf</a>, <a href="https://arxiv.org/format/2307.03154">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Strongly Correlated Electrons">cond-mat.str-el</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1038/s41467-024-46862-z">10.1038/s41467-024-46862-z <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Reversible Non-Volatile Electronic Switching in a Near Room Temperature van der Waals Ferromagnet </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Wu%2C+H">Han Wu</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+L">Lei Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Malinowski%2C+P">Paul Malinowski</a>, <a href="/search/cond-mat?searchtype=author&query=Huang%2C+J">Jianwei Huang</a>, <a href="/search/cond-mat?searchtype=author&query=Deng%2C+Q">Qinwen Deng</a>, <a href="/search/cond-mat?searchtype=author&query=Scott%2C+K">Kirsty Scott</a>, <a href="/search/cond-mat?searchtype=author&query=Jang%2C+B+G">Bo Gyu Jang</a>, <a href="/search/cond-mat?searchtype=author&query=Ruff%2C+J+P+C">Jacob P. C. Ruff</a>, <a href="/search/cond-mat?searchtype=author&query=He%2C+Y">Yu He</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+X">Xiang Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Hu%2C+C">Chaowei Hu</a>, <a href="/search/cond-mat?searchtype=author&query=Yue%2C+Z">Ziqin Yue</a>, <a href="/search/cond-mat?searchtype=author&query=Oh%2C+J+S">Ji Seop Oh</a>, <a href="/search/cond-mat?searchtype=author&query=Teng%2C+X">Xiaokun Teng</a>, <a href="/search/cond-mat?searchtype=author&query=Guo%2C+Y">Yucheng Guo</a>, <a href="/search/cond-mat?searchtype=author&query=Klemm%2C+M">Mason Klemm</a>, <a href="/search/cond-mat?searchtype=author&query=Shi%2C+C">Chuqiao Shi</a>, <a href="/search/cond-mat?searchtype=author&query=Shi%2C+Y">Yue Shi</a>, <a href="/search/cond-mat?searchtype=author&query=Setty%2C+C">Chandan Setty</a>, <a href="/search/cond-mat?searchtype=author&query=Werner%2C+T">Tyler Werner</a>, <a href="/search/cond-mat?searchtype=author&query=Hashimoto%2C+M">Makoto Hashimoto</a>, <a href="/search/cond-mat?searchtype=author&query=Lu%2C+D">Donghui Lu</a>, <a href="/search/cond-mat?searchtype=author&query=Yilmaz%2C+T">T. Yilmaz</a>, <a href="/search/cond-mat?searchtype=author&query=Vescovo%2C+E">Elio Vescovo</a>, <a href="/search/cond-mat?searchtype=author&query=Mo%2C+S">Sung-Kwan Mo</a> , et al. (15 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2307.03154v1-abstract-short" style="display: inline;"> The ability to reversibly toggle between two distinct states in a non-volatile method is important for information storage applications. Such devices have been realized for phase-change materials, which utilizes local heating methods to toggle between a crystalline and an amorphous state with distinct electrical properties. To expand such kind of switching between two topologically distinct phases… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2307.03154v1-abstract-full').style.display = 'inline'; document.getElementById('2307.03154v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2307.03154v1-abstract-full" style="display: none;"> The ability to reversibly toggle between two distinct states in a non-volatile method is important for information storage applications. Such devices have been realized for phase-change materials, which utilizes local heating methods to toggle between a crystalline and an amorphous state with distinct electrical properties. To expand such kind of switching between two topologically distinct phases requires non-volatile switching between two crystalline phases with distinct symmetries. Here we report the observation of reversible and non-volatile switching between two stable and closely-related crystal structures with remarkably distinct electronic structures in the near room temperature van der Waals ferromagnet Fe$_{5-未}$GeTe$_2$. From a combination of characterization techniques we show that the switching is enabled by the ordering and disordering of an Fe site vacancy that results in distinct crystalline symmetries of the two phases that can be controlled by a thermal annealing and quenching method. Furthermore, from symmetry analysis as well as first principle calculations, we provide understanding of the key distinction in the observed electronic structures of the two phases: topological nodal lines compatible with the preserved global inversion symmetry in the site-disordered phase, and flat bands resulting from quantum destructive interference on a bipartite crystaline lattice formed by the presence of the site order as well as the lifting of the topological degeneracy due to the broken inversion symmetry in the site-ordered phase. Our work not only reveals a rich variety of quantum phases emergent in the metallic van der Waals ferromagnets due to the presence of site ordering, but also demonstrates the potential of these highly tunable two-dimensional magnets for memory and spintronics applications. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2307.03154v1-abstract-full').style.display = 'none'; document.getElementById('2307.03154v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 6 July, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2023. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Nat Commun 15, 2739 (2024) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2307.00441">arXiv:2307.00441</a> <span> [<a href="https://arxiv.org/pdf/2307.00441">pdf</a>, <a href="https://arxiv.org/format/2307.00441">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Strongly Correlated Electrons">cond-mat.str-el</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevB.109.104410">10.1103/PhysRevB.109.104410 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Spectral Evidence for Local-Moment Ferromagnetism in van der Waals Metals Fe$_3$GaTe$_2$ and Fe$_3$GeTe$_2$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Wu%2C+H">Han Wu</a>, <a href="/search/cond-mat?searchtype=author&query=Hu%2C+C">Chaowei Hu</a>, <a href="/search/cond-mat?searchtype=author&query=Xie%2C+Y">Yaofeng Xie</a>, <a href="/search/cond-mat?searchtype=author&query=Jang%2C+B+G">Bo Gyu Jang</a>, <a href="/search/cond-mat?searchtype=author&query=Huang%2C+J">Jianwei Huang</a>, <a href="/search/cond-mat?searchtype=author&query=Guo%2C+Y">Yucheng Guo</a>, <a href="/search/cond-mat?searchtype=author&query=Wu%2C+S">Shan Wu</a>, <a href="/search/cond-mat?searchtype=author&query=Hu%2C+C">Cheng Hu</a>, <a href="/search/cond-mat?searchtype=author&query=Yue%2C+Z">Ziqin Yue</a>, <a href="/search/cond-mat?searchtype=author&query=Shi%2C+Y">Yue Shi</a>, <a href="/search/cond-mat?searchtype=author&query=Ren%2C+Z">Zheng Ren</a>, <a href="/search/cond-mat?searchtype=author&query=Yilmaz%2C+T">T. Yilmaz</a>, <a href="/search/cond-mat?searchtype=author&query=Vescovo%2C+E">Elio Vescovo</a>, <a href="/search/cond-mat?searchtype=author&query=Jozwiak%2C+C">Chris Jozwiak</a>, <a href="/search/cond-mat?searchtype=author&query=Bostwick%2C+A">Aaron Bostwick</a>, <a href="/search/cond-mat?searchtype=author&query=Rotenberg%2C+E">Eli Rotenberg</a>, <a href="/search/cond-mat?searchtype=author&query=Fedorov%2C+A">Alexei Fedorov</a>, <a href="/search/cond-mat?searchtype=author&query=Denlinger%2C+J">Jonathan Denlinger</a>, <a href="/search/cond-mat?searchtype=author&query=Klewe%2C+C">Christoph Klewe</a>, <a href="/search/cond-mat?searchtype=author&query=Shafer%2C+P">Padraic Shafer</a>, <a href="/search/cond-mat?searchtype=author&query=Lu%2C+D">Donghui Lu</a>, <a href="/search/cond-mat?searchtype=author&query=Hashimoto%2C+M">Makoto Hashimoto</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Birgeneau%2C+R+J">Robert J. Birgeneau</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+X">Xiaodong Xu</a> , et al. (4 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2307.00441v2-abstract-short" style="display: inline;"> Magnetism in two-dimensional (2D) materials has attracted considerable attention recently for both fundamental understanding of magnetism and their tunability towards device applications. The isostructural Fe$_3$GeTe$_2$ and Fe$_3$GaTe$_2$ are two members of the Fe-based van der Waals (vdW) ferromagnet family, but exhibit very different Curie temperatures (T$_C$) of 210 K and 360 K, respectively.… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2307.00441v2-abstract-full').style.display = 'inline'; document.getElementById('2307.00441v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2307.00441v2-abstract-full" style="display: none;"> Magnetism in two-dimensional (2D) materials has attracted considerable attention recently for both fundamental understanding of magnetism and their tunability towards device applications. The isostructural Fe$_3$GeTe$_2$ and Fe$_3$GaTe$_2$ are two members of the Fe-based van der Waals (vdW) ferromagnet family, but exhibit very different Curie temperatures (T$_C$) of 210 K and 360 K, respectively. Here, by using angle-resolved photoemission spectroscopy and density functional theory, we systematically compare the electronic structures of the two compounds. Qualitative similarities in the Fermi surface can be found between the two compounds, with expanded hole pockets in Fe$_3$GaTe$_2$ suggesting additional hole carriers compared to Fe$_3$GeTe$_2$. Interestingly, we observe no band shift in Fe$_3$GaTe$_2$ across its T$_C$ of 360 K, compared to a small shift in Fe$_3$GeTe$_2$ across its T$_C$ of 210 K. The weak temperature-dependent evolution strongly deviates from the expectations of an itinerant Stoner mechanism. Our results suggest that itinerant electrons have minimal contributions to the enhancement of T$_C$ in Fe$_3$GaTe$_2$ compared to Fe$_3$GeTe$_2$, and that the nature of ferromagnetism in these Fe-based vdW ferromagnets must be understood with considerations of the electron correlations. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2307.00441v2-abstract-full').style.display = 'none'; document.getElementById('2307.00441v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 2 December, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 1 July, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2023. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Physical Review B 109, 104410 (2024) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2305.02625">arXiv:2305.02625</a> <span> [<a href="https://arxiv.org/pdf/2305.02625">pdf</a>, <a href="https://arxiv.org/format/2305.02625">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Strongly Correlated Electrons">cond-mat.str-el</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Superconductivity">cond-mat.supr-con</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1063/5.0157031">10.1063/5.0157031 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Angle-resolved photoemission spectroscopy with an $\textit{in situ}$ tunable magnetic field </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Huang%2C+J">Jianwei Huang</a>, <a href="/search/cond-mat?searchtype=author&query=Yue%2C+Z">Ziqin Yue</a>, <a href="/search/cond-mat?searchtype=author&query=Baydin%2C+A">Andrey Baydin</a>, <a href="/search/cond-mat?searchtype=author&query=Zhu%2C+H">Hanyu Zhu</a>, <a href="/search/cond-mat?searchtype=author&query=Nojiri%2C+H">Hiroyuki Nojiri</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=He%2C+Y">Yu He</a>, <a href="/search/cond-mat?searchtype=author&query=Yi%2C+M">Ming Yi</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2305.02625v2-abstract-short" style="display: inline;"> Angle-resolved photoemission spectroscopy (ARPES) is a powerful tool for probing the momentum-resolved single-particle spectral function of materials. Historically, $\textit{in situ}$ magnetic fields have been carefully avoided as they are detrimental to the control of photoelectron trajectory during the photoelectron detection process. However, magnetic field is an important experimental knob for… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2305.02625v2-abstract-full').style.display = 'inline'; document.getElementById('2305.02625v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2305.02625v2-abstract-full" style="display: none;"> Angle-resolved photoemission spectroscopy (ARPES) is a powerful tool for probing the momentum-resolved single-particle spectral function of materials. Historically, $\textit{in situ}$ magnetic fields have been carefully avoided as they are detrimental to the control of photoelectron trajectory during the photoelectron detection process. However, magnetic field is an important experimental knob for both probing and tuning symmetry-breaking phases and electronic topology in quantum materials. In this paper, we introduce an easily implementable method for realizing an $\textit{in situ}$ tunable magnetic field at the sample position in an ARPES experiment and analyze magnetic field induced artifacts in ARPES data. Specifically, we identified and quantified three distinct extrinsic effects of a magnetic field: Fermi surface rotation, momentum shrinking, and momentum broadening. We examined these effects in three prototypical quantum materials, i.e., a topological insulator (Bi$_2$Se$_3$), an iron-based superconductor (LiFeAs), and a cuprate superconductor (Bi$_2$Sr$_2$CaCu$_2$O$_{8+x}$), and demonstrate the feasibility of ARPES measurements in the presence of a controllable magnetic field. Our studies lay the foundation for the future development of the technique and interpretation of ARPES measurements of field-tunable quantum phases. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2305.02625v2-abstract-full').style.display = 'none'; document.getElementById('2305.02625v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 19 May, 2024; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 4 May, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2023. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">26 pages, 7 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Rev. Sci. Instrum. 94, 093902 (2023) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2303.13820">arXiv:2303.13820</a> <span> [<a href="https://arxiv.org/pdf/2303.13820">pdf</a>, <a href="https://arxiv.org/format/2303.13820">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1364/OPTICA.491626">10.1364/OPTICA.491626 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Observation of Colossal Terahertz Magnetoresistance and Magnetocapacitance in a Perovskite Manganite </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Tay%2C+F">Fuyang Tay</a>, <a href="/search/cond-mat?searchtype=author&query=Chaudhary%2C+S">Swati Chaudhary</a>, <a href="/search/cond-mat?searchtype=author&query=He%2C+J">Jiaming He</a>, <a href="/search/cond-mat?searchtype=author&query=Peraca%2C+N+M">Nicolas Marquez Peraca</a>, <a href="/search/cond-mat?searchtype=author&query=Baydin%2C+A">Andrey Baydin</a>, <a href="/search/cond-mat?searchtype=author&query=Fiete%2C+G+A">Gregory A. Fiete</a>, <a href="/search/cond-mat?searchtype=author&query=Zhou%2C+J">Jianshi Zhou</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2303.13820v1-abstract-short" style="display: inline;"> We have studied the terahertz response of a bulk single crystal of La$_{0.875}$Sr$_{0.125}$MnO$_3$ at around its Curie temperature, observing large changes in the real and imaginary parts of the optical conductivity as a function of magnetic field. The terahertz resistance and capacitance extracted from the optical conductivity rapidly increased with increasing magnetic field and did not show any… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2303.13820v1-abstract-full').style.display = 'inline'; document.getElementById('2303.13820v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2303.13820v1-abstract-full" style="display: none;"> We have studied the terahertz response of a bulk single crystal of La$_{0.875}$Sr$_{0.125}$MnO$_3$ at around its Curie temperature, observing large changes in the real and imaginary parts of the optical conductivity as a function of magnetic field. The terahertz resistance and capacitance extracted from the optical conductivity rapidly increased with increasing magnetic field and did not show any sign of saturation up to 6 T, reaching 60% and 15%, respectively, at 180 K. The observed terahertz colossal magnetoresistance and magnetocapacitance effects can be qualitatively explained by using a two-component model that assumes the coexistence of two phases with vastly different conductivities. These results demonstrate the potential use of perovskite manganites for developing efficient terahertz devices based on magnetic modulations of the amplitude and phase of terahertz waves. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2303.13820v1-abstract-full').style.display = 'none'; document.getElementById('2303.13820v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 24 March, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2023. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">7 pages, 6 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Optica 10, 7 (2023) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2303.01866">arXiv:2303.01866</a> <span> [<a href="https://arxiv.org/pdf/2303.01866">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1021/acs.nanolett.3c00765">10.1021/acs.nanolett.3c00765 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Transition from Diffusive to Superdiffusive Transport in Carbon Nanotube Networks via Nematic Order Control </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Wais%2C+M">Michael Wais</a>, <a href="/search/cond-mat?searchtype=author&query=Bagsican%2C+F+R+G">Filchito Renee G. Bagsican</a>, <a href="/search/cond-mat?searchtype=author&query=Komatsu%2C+N">Natsumi Komatsu</a>, <a href="/search/cond-mat?searchtype=author&query=Gao%2C+W">Weilu Gao</a>, <a href="/search/cond-mat?searchtype=author&query=Serita%2C+K">Kazunori Serita</a>, <a href="/search/cond-mat?searchtype=author&query=Murakami%2C+H">Hironaru Murakami</a>, <a href="/search/cond-mat?searchtype=author&query=Held%2C+K">Karsten Held</a>, <a href="/search/cond-mat?searchtype=author&query=Kawayama%2C+I">Iwao Kawayama</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Battiato%2C+M">Marco Battiato</a>, <a href="/search/cond-mat?searchtype=author&query=Tonouchi%2C+M">Masayoshi Tonouchi</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2303.01866v2-abstract-short" style="display: inline;"> The one-dimensional confinement of quasiparticles in individual carbon nanotubes (CNTs) leads to extremely anisotropic electronic and optical properties. In a macroscopic ensemble of randomly oriented CNTs, this anisotropy disappears together with other properties that make them attractive for certain device applications. The question however remains if not only anisotropy, but other types of beha… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2303.01866v2-abstract-full').style.display = 'inline'; document.getElementById('2303.01866v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2303.01866v2-abstract-full" style="display: none;"> The one-dimensional confinement of quasiparticles in individual carbon nanotubes (CNTs) leads to extremely anisotropic electronic and optical properties. In a macroscopic ensemble of randomly oriented CNTs, this anisotropy disappears together with other properties that make them attractive for certain device applications. The question however remains if not only anisotropy, but other types of behaviours are suppressed by disorder. Here, we compare the dynamics of quasiparticles under strong electric fields in aligned and random CNT networks using a combination of terahertz emission and photocurrent experiments and out-of-equilibrium numerical simulations. We find that the degree of alignment strongly influences the excited quasiparticles' dynamics, rerouting the thermalisation pathways. This is, in particular, evidenced in the high-energy, high-momentum electronic population (probed through the formation of low energy excitons via exciton impact ionization) and the transport regime evolving from diffusive to superdiffusive. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2303.01866v2-abstract-full').style.display = 'none'; document.getElementById('2303.01866v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 11 May, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 3 March, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2023. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">17 pages, 5 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2302.12227">arXiv:2302.12227</a> <span> [<a href="https://arxiv.org/pdf/2302.12227">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Strongly Correlated Electrons">cond-mat.str-el</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1038/s41535-024-00623-9">10.1038/s41535-024-00623-9 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Nanoscale visualization and spectral fingerprints of the charge order in ScV6Sn6 distinct from other kagome metals </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Cheng%2C+S">Siyu Cheng</a>, <a href="/search/cond-mat?searchtype=author&query=Ren%2C+Z">Zheng Ren</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+H">Hong Li</a>, <a href="/search/cond-mat?searchtype=author&query=Oh%2C+J">Jiseop Oh</a>, <a href="/search/cond-mat?searchtype=author&query=Tan%2C+H">Hengxin Tan</a>, <a href="/search/cond-mat?searchtype=author&query=Pokharel%2C+G">Ganesh Pokharel</a>, <a href="/search/cond-mat?searchtype=author&query=DeStefano%2C+J+M">Jonathan M. DeStefano</a>, <a href="/search/cond-mat?searchtype=author&query=Rosenberg%2C+E">Elliott Rosenberg</a>, <a href="/search/cond-mat?searchtype=author&query=Guo%2C+Y">Yucheng Guo</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+Y">Yichen Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Yue%2C+Z">Ziqin Yue</a>, <a href="/search/cond-mat?searchtype=author&query=Lee%2C+Y">Yongbin Lee</a>, <a href="/search/cond-mat?searchtype=author&query=Gorovikov%2C+S">Sergey Gorovikov</a>, <a href="/search/cond-mat?searchtype=author&query=Zonno%2C+M">Marta Zonno</a>, <a href="/search/cond-mat?searchtype=author&query=Hashimoto%2C+M">Makoto Hashimoto</a>, <a href="/search/cond-mat?searchtype=author&query=Lu%2C+D">Donghui Lu</a>, <a href="/search/cond-mat?searchtype=author&query=Ke%2C+L">Liqin Ke</a>, <a href="/search/cond-mat?searchtype=author&query=Mazzola%2C+F">Federico Mazzola</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Birgeneau%2C+R+J">R. J. Birgeneau</a>, <a href="/search/cond-mat?searchtype=author&query=Chu%2C+J">Jiun-Haw Chu</a>, <a href="/search/cond-mat?searchtype=author&query=Wilson%2C+S+D">Stephen D. Wilson</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%2C+Z">Ziqiang Wang</a>, <a href="/search/cond-mat?searchtype=author&query=Yan%2C+B">Binghai Yan</a>, <a href="/search/cond-mat?searchtype=author&query=Yi%2C+M">Ming Yi</a> , et al. (1 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2302.12227v1-abstract-short" style="display: inline;"> Charge density waves (CDWs) have been tied to a number of unusual phenomena in kagome metals, including rotation symmetry breaking, time-reversal symmetry breaking and superconductivity. The majority of the experiments thus far have focused on the CDW states in AV3Sb5 and FeGe, characterized by the 2a0 by 2a0 period. Recently, a bulk CDW phase (T* ~ 92 K) with a different wave length and orientati… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2302.12227v1-abstract-full').style.display = 'inline'; document.getElementById('2302.12227v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2302.12227v1-abstract-full" style="display: none;"> Charge density waves (CDWs) have been tied to a number of unusual phenomena in kagome metals, including rotation symmetry breaking, time-reversal symmetry breaking and superconductivity. The majority of the experiments thus far have focused on the CDW states in AV3Sb5 and FeGe, characterized by the 2a0 by 2a0 period. Recently, a bulk CDW phase (T* ~ 92 K) with a different wave length and orientation has been reported in ScV6Sn6, as the first realization of a CDW state in the broad RM6X6 structure. Here, using a combination of scanning tunneling microscopy/spectroscopy and angle-resolved photoemission spectroscopy, we reveal the microscopic structure and the spectroscopic signatures of this charge ordering phase in ScV6Sn6. Differential conductance dI/dV spectra show a partial gap opening in the density-of-states of about 20 meV at the Fermi level. This is much smaller than the spectral gaps observed in AV3Sb5 and FeGe despite the comparable T* temperatures in these systems, suggesting substantially weaker coupling strength in ScV6Sn6. Surprisingly, despite the three-dimensional bulk nature of the charge order, we find that the charge modulation is only observed on the kagome termination. Temperature-dependent band structure evolution suggests a modulation of the surface states as a consequence of the emergent charge order, with an abrupt spectral weight shift below T* consistent with the first-order phase transition. The similarity of the electronic band structures of ScV6Sn6 and TbV6Sn6 (where charge ordering is absent), together with the first-principle calculations, suggests that charge ordering in ScV6Sn6 may not be primarily electronically driven. Interestingly, in contrast to the CDW state of cousin AV3Sb5, we find no evidence supporting rotation symmetry breaking. Our results reveal a distinctive nature of the charge ordering phase in ScV6Sn6 in comparison to other kagome metals. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2302.12227v1-abstract-full').style.display = 'none'; document.getElementById('2302.12227v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 23 February, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2023. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> npj Quantum Mater. 9, 14 (2024) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2301.12311">arXiv:2301.12311</a> <span> [<a href="https://arxiv.org/pdf/2301.12311">pdf</a>, <a href="https://arxiv.org/format/2301.12311">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> </div> <p class="title is-5 mathjax"> Controlled synthetic chirality in macroscopic assemblies of carbon nanotubes </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Doumani%2C+J">Jacques Doumani</a>, <a href="/search/cond-mat?searchtype=author&query=Lou%2C+M">Minhan Lou</a>, <a href="/search/cond-mat?searchtype=author&query=Dewey%2C+O">Oliver Dewey</a>, <a href="/search/cond-mat?searchtype=author&query=Hong%2C+N">Nina Hong</a>, <a href="/search/cond-mat?searchtype=author&query=Fan%2C+J">Jichao Fan</a>, <a href="/search/cond-mat?searchtype=author&query=Baydin%2C+A">Andrey Baydin</a>, <a href="/search/cond-mat?searchtype=author&query=Yomogida%2C+Y">Yohei Yomogida</a>, <a href="/search/cond-mat?searchtype=author&query=Yanagi%2C+K">Kazuhiro Yanagi</a>, <a href="/search/cond-mat?searchtype=author&query=Pasquali%2C+M">Matteo Pasquali</a>, <a href="/search/cond-mat?searchtype=author&query=Saito%2C+R">Riichiro Saito</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Gao%2C+W">Weilu Gao</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2301.12311v1-abstract-short" style="display: inline;"> There is an emerging recognition that successful utilization of chiral degrees of freedom can bring new scientific and technological opportunities to diverse research areas. Hence, methods are being sought for creating artificial matter with controllable chirality in an uncomplicated and reproducible manner. Here, we report the development of two straightforward methods for fabricating wafer-scale… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2301.12311v1-abstract-full').style.display = 'inline'; document.getElementById('2301.12311v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2301.12311v1-abstract-full" style="display: none;"> There is an emerging recognition that successful utilization of chiral degrees of freedom can bring new scientific and technological opportunities to diverse research areas. Hence, methods are being sought for creating artificial matter with controllable chirality in an uncomplicated and reproducible manner. Here, we report the development of two straightforward methods for fabricating wafer-scale chiral architectures of ordered carbon nanotubes (CNTs) with tunable and giant circular dichroism (CD). Both methods employ simple approaches, (i) mechanical rotation and (ii) twist-stacking, based on controlled vacuum filtration and do not involve any sophisticated nanofabrication processes. We used a racemic mixture of CNTs as the starting material, so the intrinsic chirality of chiral CNTs is not responsible for the observed chirality. In particular, by controlling the stacking angle and handedness in (ii), we were able to maximize the CD response and achieve a record-high deep-ultraviolet ellipticity of 40 $\pm$ 1 mdeg/nm. Our theoretical simulations using the transfer matrix method reproduce the salient features of the experimentally observed CD spectra and further predict that a film of twist-stacked CNTs with an optimized thickness will exhibit an ellipticity as high as 150 mdeg/nm. The created wafer-scale objects represent a new class of synthetic chiral matter consisting of ordered quantum wires whose macroscopic properties are governed by nanoscopic electronic signatures such as van Hove singularities. These artificial structures with engineered chirality will not only provide playgrounds for uncovering new chiral phenomena but also open up new opportunities for developing high-performance chiral photonic and optoelectronic devices. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2301.12311v1-abstract-full').style.display = 'none'; document.getElementById('2301.12311v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 28 January, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2023. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Main text: 4 figures, 21 pages; SI: 9 figures, 1 table, 11 pages</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2210.13538">arXiv:2210.13538</a> <span> [<a href="https://arxiv.org/pdf/2210.13538">pdf</a>, <a href="https://arxiv.org/format/2210.13538">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1038/s42005-023-01257-2">10.1038/s42005-023-01257-2 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Kramers nodal lines and Weyl fermions in SmAlSi </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+Y">Yichen Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Gao%2C+Y">Yuxiang Gao</a>, <a href="/search/cond-mat?searchtype=author&query=Gao%2C+X">Xue-Jian Gao</a>, <a href="/search/cond-mat?searchtype=author&query=Lei%2C+S">Shiming Lei</a>, <a href="/search/cond-mat?searchtype=author&query=Ni%2C+Z">Zhuoliang Ni</a>, <a href="/search/cond-mat?searchtype=author&query=Oh%2C+J+S">Ji Seop Oh</a>, <a href="/search/cond-mat?searchtype=author&query=Huang%2C+J">Jianwei Huang</a>, <a href="/search/cond-mat?searchtype=author&query=Yue%2C+Z">Ziqin Yue</a>, <a href="/search/cond-mat?searchtype=author&query=Zonno%2C+M">Marta Zonno</a>, <a href="/search/cond-mat?searchtype=author&query=Gorovikov%2C+S">Sergey Gorovikov</a>, <a href="/search/cond-mat?searchtype=author&query=Hashimoto%2C+M">Makoto Hashimoto</a>, <a href="/search/cond-mat?searchtype=author&query=Lu%2C+D">Donghui Lu</a>, <a href="/search/cond-mat?searchtype=author&query=Denlinger%2C+J+D">Jonathan D. Denlinger</a>, <a href="/search/cond-mat?searchtype=author&query=Birgeneau%2C+R+J">Robert J. Birgeneau</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Wu%2C+L">Liang Wu</a>, <a href="/search/cond-mat?searchtype=author&query=Law%2C+K+T">Kam Tuen Law</a>, <a href="/search/cond-mat?searchtype=author&query=Morosan%2C+E">Emilia Morosan</a>, <a href="/search/cond-mat?searchtype=author&query=Yi%2C+M">Ming Yi</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2210.13538v3-abstract-short" style="display: inline;"> Kramers nodal lines (KNLs) have recently been proposed theoretically as a special type of Weyl line degeneracy connecting time-reversal invariant momenta. KNLs are robust to spin orbit coupling and are inherent to all non-centrosymmetric achiral crystal structures, leading to unusual spin, magneto-electric, and optical properties. However, their existence in in real quantum materials has not been… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2210.13538v3-abstract-full').style.display = 'inline'; document.getElementById('2210.13538v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2210.13538v3-abstract-full" style="display: none;"> Kramers nodal lines (KNLs) have recently been proposed theoretically as a special type of Weyl line degeneracy connecting time-reversal invariant momenta. KNLs are robust to spin orbit coupling and are inherent to all non-centrosymmetric achiral crystal structures, leading to unusual spin, magneto-electric, and optical properties. However, their existence in in real quantum materials has not been experimentally established. Here we gather the experimental evidence pointing at the presence of KNLs in SmAlSi, a non-centrosymmetric metal that develops incommensurate spin density wave order at low temperature. Using angle-resolved photoemission spectroscopy, density functional theory calculations, and magneto-transport methods, we provide evidence suggesting the presence of KNLs, together with observing Weyl fermions under the broken inversion symmetry in the paramagnetic phase of SmAlSi. We discuss the nesting possibilities regarding the emergent magnetic orders in SmAlSi. Our results provide a solid basis of experimental observations for exploring correlated topology in SmAlSi. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2210.13538v3-abstract-full').style.display = 'none'; document.getElementById('2210.13538v3-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 9 June, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 24 October, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2022. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">40 pages, 5 figures, 1 table</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Commun. Phys. 6, 134 (2023) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2209.09468">arXiv:2209.09468</a> <span> [<a href="https://arxiv.org/pdf/2209.09468">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> </div> <p class="title is-5 mathjax"> Terahertz spin dynamics in rare-earth orthoferrites </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Li%2C+X">Xinwei Li</a>, <a href="/search/cond-mat?searchtype=author&query=Kim%2C+D">Dasom Kim</a>, <a href="/search/cond-mat?searchtype=author&query=Liu%2C+Y">Yincheng Liu</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2209.09468v1-abstract-short" style="display: inline;"> Recent interest in developing fast spintronic devices and laser-controllable magnetic solids has sparked tremendous experimental and theoretical efforts to understand and manipulate ultrafast dynamics in materials. Studies of spin dynamics in the terahertz (THz) frequency range are particularly important for elucidating microscopic pathways toward novel device functionalities. Here, we review THz… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2209.09468v1-abstract-full').style.display = 'inline'; document.getElementById('2209.09468v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2209.09468v1-abstract-full" style="display: none;"> Recent interest in developing fast spintronic devices and laser-controllable magnetic solids has sparked tremendous experimental and theoretical efforts to understand and manipulate ultrafast dynamics in materials. Studies of spin dynamics in the terahertz (THz) frequency range are particularly important for elucidating microscopic pathways toward novel device functionalities. Here, we review THz phenomena related to spin dynamics in rare-earth orthoferrites, a class of materials promising for antiferromagnetic spintronics. We expand this topic into a description of four key elements. (1) We start by describing THz spectroscopy of spin excitations for probing magnetic phase transitions in thermal equilibrium. While acoustic magnons are useful indicators of spin reorientation transitions, electromagnons that arise from dynamic magnetoelectric couplings serve as a signature of inversion-symmetry-breaking phases at low temperatures. (2) We then review the strong laser driving scenario, where the system is excited far from equilibrium and thereby subject to modifications to the free energy landscape. Microscopic pathways for ultrafast laser manipulation of magnetic order are discussed. (3) Furthermore, we review a variety of protocols to manipulate coherent THz magnons in time and space, which are useful capabilities for antiferromagnetic spintronic applications. (4) Finally, new insights on the connection between dynamic magnetic coupling in condensed matter and the Dicke superradiant phase transition in quantum optics are provided. By presenting a review on an array of THz spin phenomena occurring in a single class of materials, we hope to trigger interdisciplinary efforts that actively seek connections between subfields of spintronics, which will facilitate the invention of new protocols of active spin control and quantum phase engineering. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2209.09468v1-abstract-full').style.display = 'none'; document.getElementById('2209.09468v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 20 September, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2022. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2208.12235">arXiv:2208.12235</a> <span> [<a href="https://arxiv.org/pdf/2208.12235">pdf</a>, <a href="https://arxiv.org/format/2208.12235">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1126/sciadv.adj4074">10.1126/sciadv.adj4074 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Chiral Phonons with Giant Magnetic Moments in a Topological Crystalline Insulator </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Hernandez%2C+F+G+G">Felix G. G. Hernandez</a>, <a href="/search/cond-mat?searchtype=author&query=Baydin%2C+A">Andrey Baydin</a>, <a href="/search/cond-mat?searchtype=author&query=Chaudhary%2C+S">Swati Chaudhary</a>, <a href="/search/cond-mat?searchtype=author&query=Tay%2C+F">Fuyang Tay</a>, <a href="/search/cond-mat?searchtype=author&query=Katayama%2C+I">Ikufumi Katayama</a>, <a href="/search/cond-mat?searchtype=author&query=Takeda%2C+J">Jun Takeda</a>, <a href="/search/cond-mat?searchtype=author&query=Nojiri%2C+H">Hiroyuki Nojiri</a>, <a href="/search/cond-mat?searchtype=author&query=Okazaki%2C+A+K">Anderson K. Okazaki</a>, <a href="/search/cond-mat?searchtype=author&query=Rappl%2C+P+H+O">Paulo H. O. Rappl</a>, <a href="/search/cond-mat?searchtype=author&query=Abramof%2C+E">Eduardo Abramof</a>, <a href="/search/cond-mat?searchtype=author&query=Rodriguez-Vega%2C+M">Martin Rodriguez-Vega</a>, <a href="/search/cond-mat?searchtype=author&query=Fiete%2C+G+A">Gregory A. Fiete</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2208.12235v3-abstract-short" style="display: inline;"> We have studied the magnetic response of transverse optical phonons in Pb$_{1-x}$Sn$_{x}$Te films. Polarization-dependent terahertz magnetospectroscopy measurements revealed Zeeman splittings and diamagnetic shifts, demonstrating that these phonon modes become chiral in magnetic fields. Films in the topological crystalline insulator phase ($x > 0.32$) exhibited magnetic moment values that are larg… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2208.12235v3-abstract-full').style.display = 'inline'; document.getElementById('2208.12235v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2208.12235v3-abstract-full" style="display: none;"> We have studied the magnetic response of transverse optical phonons in Pb$_{1-x}$Sn$_{x}$Te films. Polarization-dependent terahertz magnetospectroscopy measurements revealed Zeeman splittings and diamagnetic shifts, demonstrating that these phonon modes become chiral in magnetic fields. Films in the topological crystalline insulator phase ($x > 0.32$) exhibited magnetic moment values that are larger than those for topologically trivial films ($x < 0.32$) by two orders of magnitude. Furthermore, the sign of the effective $g$-factor was opposite in the two phases, which can be explained by our theoretical model. These results strongly indicate the existence of interplay between the magnetic properties of chiral phonons and the topology of electronic band structure. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2208.12235v3-abstract-full').style.display = 'none'; document.getElementById('2208.12235v3-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 16 January, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 25 August, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2022. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">6 pages, 3 figures, see Supplemental Material in the Ancillary directory</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2208.10030">arXiv:2208.10030</a> <span> [<a href="https://arxiv.org/pdf/2208.10030">pdf</a>, <a href="https://arxiv.org/format/2208.10030">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> </div> <p class="title is-5 mathjax"> Magnetically Tuned Continuous Transition from Weak to Strong Coupling in Terahertz Magnon Polaritons </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Baydin%2C+A">Andrey Baydin</a>, <a href="/search/cond-mat?searchtype=author&query=Hayashida%2C+K">Kenji Hayashida</a>, <a href="/search/cond-mat?searchtype=author&query=Makihara%2C+T">Takuma Makihara</a>, <a href="/search/cond-mat?searchtype=author&query=Tay%2C+F">Fuyang Tay</a>, <a href="/search/cond-mat?searchtype=author&query=Ma%2C+X">Xiaoxuan Ma</a>, <a href="/search/cond-mat?searchtype=author&query=Ren%2C+W">Wei Ren</a>, <a href="/search/cond-mat?searchtype=author&query=Ma%2C+G">Guohong Ma</a>, <a href="/search/cond-mat?searchtype=author&query=Noe%2C+G+T">G. Timothy Noe II</a>, <a href="/search/cond-mat?searchtype=author&query=Katayama%2C+I">Ikufumi Katayama</a>, <a href="/search/cond-mat?searchtype=author&query=Takeda%2C+J">Jun Takeda</a>, <a href="/search/cond-mat?searchtype=author&query=Nojiri%2C+H">Hiroyuki Nojiri</a>, <a href="/search/cond-mat?searchtype=author&query=Cao%2C+S">Shixun Cao</a>, <a href="/search/cond-mat?searchtype=author&query=Bamba%2C+M">Motoaki Bamba</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2208.10030v1-abstract-short" style="display: inline;"> Depending on the relative rates of coupling and dissipation, a light-matter coupled system is either in the weak- or strong-coupling regime. Here, we present a unique system where the coupling rate continuously increases with an externally applied magnetic field while the dissipation rate remains constant, allowing us to monitor a weak-to-strong coupling transition as a function of magnetic field.… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2208.10030v1-abstract-full').style.display = 'inline'; document.getElementById('2208.10030v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2208.10030v1-abstract-full" style="display: none;"> Depending on the relative rates of coupling and dissipation, a light-matter coupled system is either in the weak- or strong-coupling regime. Here, we present a unique system where the coupling rate continuously increases with an externally applied magnetic field while the dissipation rate remains constant, allowing us to monitor a weak-to-strong coupling transition as a function of magnetic field. We observed a Rabi splitting of a terahertz magnon mode in yttrium orthoferrite above a threshold magnetic field of ~14 T. Based on a microscopic theoretical model, we show that with increasing magnetic field the magnons transition into magnon polaritons through an exceptional point, which will open up new opportunities for in situ control of non-Hermitian systems. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2208.10030v1-abstract-full').style.display = 'none'; document.getElementById('2208.10030v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 21 August, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2022. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2205.13382">arXiv:2205.13382</a> <span> [<a href="https://arxiv.org/pdf/2205.13382">pdf</a>, <a href="https://arxiv.org/format/2205.13382">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Strongly Correlated Electrons">cond-mat.str-el</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3389/femat.2022.934691">10.3389/femat.2022.934691 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Is the optical conductivity of heavy fermion strange metals Planckian? </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Li%2C+X">Xinwei Li</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Si%2C+Q">Qimiao Si</a>, <a href="/search/cond-mat?searchtype=author&query=Paschen%2C+S">Silke Paschen</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2205.13382v2-abstract-short" style="display: inline;"> Strange metal behavior appears across a variety of condensed matter settings and beyond, and achieving a universal understanding is an exciting prospect. The beyond-Landau quantum criticality of Kondo destruction has had considerable success in describing the behavior of strange metal heavy fermion compounds, and there is some evidence that the associated partial localization-delocalization nature… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2205.13382v2-abstract-full').style.display = 'inline'; document.getElementById('2205.13382v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2205.13382v2-abstract-full" style="display: none;"> Strange metal behavior appears across a variety of condensed matter settings and beyond, and achieving a universal understanding is an exciting prospect. The beyond-Landau quantum criticality of Kondo destruction has had considerable success in describing the behavior of strange metal heavy fermion compounds, and there is some evidence that the associated partial localization-delocalization nature can be generalized to diverse materials classes. Other potential overarching principles at play are also being explored. An intriguing proposal is that Planckian scattering, with a rate of $k_{\rm B}T/\hbar$, leads to the linear temperature dependence of the (dc) electrical resistivity, which is a hallmark of strange metal behavior. Here we extend a previously introduced analysis scheme based on the Drude description of the dc resistivity to optical conductivity data. When they are well described by a simple (ac) Drude model, the scattering rate can be directly extracted. This avoids the need to determine the ratio of charge carrier concentration to effective mass, which has complicated previous analyses based on the dc resistivity. However, we point out that strange metals typically exhibit strong deviations from Drude behavior, as exemplified by the ``extreme'' strange metal YbRh$_2$Si$_2$. This calls for alternative approaches, and we point to the power of strange metal dynamical (energy-over-temperature) scaling analyses for the inelastic part of the optical conductivity. If such scaling extends to the low-frequency limit, a strange metal relaxation rate can be estimated, and may ultimately be used to test whether strange metals relax in a Planckian manner. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2205.13382v2-abstract-full').style.display = 'none'; document.getElementById('2205.13382v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 1 January, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 26 May, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2022. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Perspective in the invited issue "New Heavy Fermion Superconductors", Frontiers in Electronic Materials; 21 pages, 7 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2201.06693">arXiv:2201.06693</a> <span> [<a href="https://arxiv.org/pdf/2201.06693">pdf</a>, <a href="https://arxiv.org/format/2201.06693">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevLett.130.176303">10.1103/PhysRevLett.130.176303 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Evidence for Phonon-Assisted Intertube Electronic Transport in an Armchair Carbon Nanotube Film </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Adinehloo%2C+D">Davoud Adinehloo</a>, <a href="/search/cond-mat?searchtype=author&query=Gao%2C+W">Weilu Gao</a>, <a href="/search/cond-mat?searchtype=author&query=Mojibpour%2C+A">Ali Mojibpour</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Perebeinos%2C+V">Vasili Perebeinos</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2201.06693v1-abstract-short" style="display: inline;"> The electrical conductivity of a macroscopic assembly of nanomaterials is determined through a complex interplay of electronic transport within and between constituent nano-objects. Phonons play dual roles in this situation: their increased populations tend to reduce the conductivity via electron scattering while they can boost the conductivity by assisting electrons to propagate through the poten… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2201.06693v1-abstract-full').style.display = 'inline'; document.getElementById('2201.06693v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2201.06693v1-abstract-full" style="display: none;"> The electrical conductivity of a macroscopic assembly of nanomaterials is determined through a complex interplay of electronic transport within and between constituent nano-objects. Phonons play dual roles in this situation: their increased populations tend to reduce the conductivity via electron scattering while they can boost the conductivity by assisting electrons to propagate through the potential-energy landscape. Here, we identify a phonon-assisted coherent electron transport process between neighboring nanotubes in temperature-dependent conductivity measurements on a macroscopic film of armchair single-wall carbon nanotubes. Through atomistic modeling of electronic states and calculations of both electronic and phonon-assisted junction conductances, we conclude that phonon-assisted conductance is the dominant mechanism for the observed high-temperature transport. The unambiguous manifestation of coherent intertube dynamics proves a single-chirality armchair nanotube film to be a unique macroscopic solid-state ensemble of nano-objects promising for the development of room-temperature coherent electronic devices. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2201.06693v1-abstract-full').style.display = 'none'; document.getElementById('2201.06693v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 17 January, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2022. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">6 pages, 3 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2107.08659">arXiv:2107.08659</a> <span> [<a href="https://arxiv.org/pdf/2107.08659">pdf</a>, <a href="https://arxiv.org/format/2107.08659">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Computational Physics">physics.comp-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1016/j.carbon.2021.10.048">10.1016/j.carbon.2021.10.048 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Origin of the Background Absorption in Carbon Nanotubes: Phonon-Assisted Excitonic Continuum </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Forno%2C+S+D">Stefano Dal Forno</a>, <a href="/search/cond-mat?searchtype=author&query=Komatsu%2C+N">Natsumi Komatsu</a>, <a href="/search/cond-mat?searchtype=author&query=Wais%2C+M">Michael Wais</a>, <a href="/search/cond-mat?searchtype=author&query=Mojibpour%2C+A">Ali Mojibpour</a>, <a href="/search/cond-mat?searchtype=author&query=Wadgaonkar%2C+I">Indrajit Wadgaonkar</a>, <a href="/search/cond-mat?searchtype=author&query=Ghosh%2C+S">Saunab Ghosh</a>, <a href="/search/cond-mat?searchtype=author&query=Yomogida%2C+Y">Yohei Yomogida</a>, <a href="/search/cond-mat?searchtype=author&query=Yanagi%2C+K">Kazuhiro Yanagi</a>, <a href="/search/cond-mat?searchtype=author&query=Held%2C+K">Karsten Held</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Battiato%2C+M">Marco Battiato</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2107.08659v1-abstract-short" style="display: inline;"> Excitonic effects in 1D semiconductors can be qualitatively different from those in higher dimensions. In particular, the Sommerfeld factor, the ratio of the above-band-edge excitonic continuum absorption to free electron-hole pair generation, has been shown to be less than 1 (i.e., suppressed) in 1D systems while it is larger than1 (i.e., enhanced) in 2D and 3D systems. Strong continuum suppressi… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2107.08659v1-abstract-full').style.display = 'inline'; document.getElementById('2107.08659v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2107.08659v1-abstract-full" style="display: none;"> Excitonic effects in 1D semiconductors can be qualitatively different from those in higher dimensions. In particular, the Sommerfeld factor, the ratio of the above-band-edge excitonic continuum absorption to free electron-hole pair generation, has been shown to be less than 1 (i.e., suppressed) in 1D systems while it is larger than1 (i.e., enhanced) in 2D and 3D systems. Strong continuum suppression indeed exists in semiconducting single-wall carbon nanotubes, a prototypical 1D semiconductor. However, absorption spectra for carbon nanotubes are typically fit with a combination of Lorentzians and a polynomial background baseline with little physical meaning. Here, we performed absorption measurements in aligned single-chirality (6,5) carbon nanotube films. The obtained spectra were fit with our theoretical model obtained by solving the Boltzmann scattering equation (i.e., the quantum Fokker-Planck equation), involving fifty-nine different types of transitions among three different types of quasiparticles. Specifically, we took into account microscopic interactions between photons, phonons, and excitons, including their dispersions, which unambiguously demonstrated that the background absorption is due to phonon-assisted transitions from the semiconductor vacuum to finite-momentum continuum states of excitons. The excellent agreement we obtained between experiment and theory suggests that our numerical technique can be seamlessly extended to compute strongly out-of-equilibrium many-body dynamics and time-resolved spectra in low-dimensional materials. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2107.08659v1-abstract-full').style.display = 'none'; document.getElementById('2107.08659v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 19 July, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2021. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2107.07616">arXiv:2107.07616</a> <span> [<a href="https://arxiv.org/pdf/2107.07616">pdf</a>, <a href="https://arxiv.org/format/2107.07616">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevLett.128.075901">10.1103/PhysRevLett.128.075901 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Magnetic Control of Soft Chiral Phonons in PbTe </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Baydin%2C+A">Andrey Baydin</a>, <a href="/search/cond-mat?searchtype=author&query=Hernandez%2C+F+G+G">Felix G. G. Hernandez</a>, <a href="/search/cond-mat?searchtype=author&query=Rodriguez-Vega%2C+M">Martin Rodriguez-Vega</a>, <a href="/search/cond-mat?searchtype=author&query=Okazaki%2C+A+K">Anderson K. Okazaki</a>, <a href="/search/cond-mat?searchtype=author&query=Tay%2C+F">Fuyang Tay</a>, <a href="/search/cond-mat?searchtype=author&query=Noe%2C+G+T">G. Timothy Noe II</a>, <a href="/search/cond-mat?searchtype=author&query=Katayama%2C+I">Ikufumi Katayama</a>, <a href="/search/cond-mat?searchtype=author&query=Takeda%2C+J">Jun Takeda</a>, <a href="/search/cond-mat?searchtype=author&query=Nojiri%2C+H">Hiroyuki Nojiri</a>, <a href="/search/cond-mat?searchtype=author&query=Rappl%2C+P+H+O">Paulo H. O. Rappl</a>, <a href="/search/cond-mat?searchtype=author&query=Abramof%2C+E">Eduardo Abramof</a>, <a href="/search/cond-mat?searchtype=author&query=Fiete%2C+G+A">Gregory A. Fiete</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2107.07616v2-abstract-short" style="display: inline;"> PbTe crystals have a soft transverse optical phonon mode in the terahertz frequency range, which is known to efficiently decay into heat-carrying acoustic phonons, resulting in anomalously low thermal conductivity. Here, we studied this phonon via polarization-dependent terahertz spectroscopy. We observed softening of this mode with decreasing temperature, indicative of incipient ferroelectricity,… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2107.07616v2-abstract-full').style.display = 'inline'; document.getElementById('2107.07616v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2107.07616v2-abstract-full" style="display: none;"> PbTe crystals have a soft transverse optical phonon mode in the terahertz frequency range, which is known to efficiently decay into heat-carrying acoustic phonons, resulting in anomalously low thermal conductivity. Here, we studied this phonon via polarization-dependent terahertz spectroscopy. We observed softening of this mode with decreasing temperature, indicative of incipient ferroelectricity, which we explain through a model including strong anharmonicity with a quartic displacement term. In magnetic fields up to 25T, the phonon mode split into two modes with opposite handedness, exhibiting circular dichroism. Their frequencies displayed Zeeman splitting together with an overall diamagnetic shift with increasing magnetic field. Using a group-theoretical approach, we demonstrate that these observations are results of magnetic field-induced morphic changes in the crystal symmetries through the Lorentz force exerted on the lattice ions. This study thus reveals a novel process of controlling phonon properties in a soft ionic lattice by a strong magnetic field. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2107.07616v2-abstract-full').style.display = 'none'; document.getElementById('2107.07616v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 18 February, 2022; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 15 July, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2021. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Lett. 128, 075901 (2022) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2101.07503">arXiv:2101.07503</a> <span> [<a href="https://arxiv.org/pdf/2101.07503">pdf</a>, <a href="https://arxiv.org/format/2101.07503">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1016/j.carbon.2021.07.057">10.1016/j.carbon.2021.07.057 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Band Structure Dependent Electronic Localization in Macroscopic Films of Single-Chirality Single-Wall Carbon Nanotubes </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Gao%2C+W">Weilu Gao</a>, <a href="/search/cond-mat?searchtype=author&query=Adinehloo%2C+D">Davoud Adinehloo</a>, <a href="/search/cond-mat?searchtype=author&query=Mojibpour%2C+A">Ali Mojibpour</a>, <a href="/search/cond-mat?searchtype=author&query=Yomogida%2C+Y">Yohei Yomogida</a>, <a href="/search/cond-mat?searchtype=author&query=Hirano%2C+A">Atsushi Hirano</a>, <a href="/search/cond-mat?searchtype=author&query=Tanaka%2C+T">Takeshi Tanaka</a>, <a href="/search/cond-mat?searchtype=author&query=Kataura%2C+H">Hiromichi Kataura</a>, <a href="/search/cond-mat?searchtype=author&query=Zheng%2C+M">Ming Zheng</a>, <a href="/search/cond-mat?searchtype=author&query=Perebeinos%2C+V">Vasili Perebeinos</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2101.07503v3-abstract-short" style="display: inline;"> Significant understanding has been achieved over the last few decades regarding chirality-dependent properties of single-wall carbon nanotubes (SWCNTs), primarily through single-tube studies. However, macroscopic manifestations of chirality dependence have been limited, especially in electronic transport, despite the fact that such distinct behaviors are needed for many applications of SWCNT-based… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2101.07503v3-abstract-full').style.display = 'inline'; document.getElementById('2101.07503v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2101.07503v3-abstract-full" style="display: none;"> Significant understanding has been achieved over the last few decades regarding chirality-dependent properties of single-wall carbon nanotubes (SWCNTs), primarily through single-tube studies. However, macroscopic manifestations of chirality dependence have been limited, especially in electronic transport, despite the fact that such distinct behaviors are needed for many applications of SWCNT-based devices. In addition, developing reliable transport theory is challenging since a description of localization phenomena in an assembly of nanoobjects requires precise knowledge of disorder on multiple spatial scales, particularly if the ensemble is heterogeneous. Here, we report an observation of pronounced chirality-dependent electronic localization in temperature and magnetic field dependent conductivity measurements on macroscopic films of single-chirality SWCNTs. The samples included large-gap semiconducting (6,5) and (10,3) films, narrow-gap semiconducting (7,4) and (8,5) films, and armchair metallic (6,6) films. Experimental data and theoretical calculations revealed Mott variable-range-hopping dominated transport in all samples, while localization lengths fall into three distinct categories depending on their band gaps. Armchair films have the largest localization length. Our detailed analyses on electronic transport properties of single-chirality SWCNT films provide significant new insight into electronic transport in ensembles of nanoobjects, offering foundations for designing and deploying macroscopic SWCNT solid-state devices. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2101.07503v3-abstract-full').style.display = 'none'; document.getElementById('2101.07503v3-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 20 September, 2021; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 19 January, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2021. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">4 figures, 1 table, 25 pages</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Carbon 183, 774 (2021) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2008.10721">arXiv:2008.10721</a> <span> [<a href="https://arxiv.org/pdf/2008.10721">pdf</a>, <a href="https://arxiv.org/format/2008.10721">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Quantum Gases">cond-mat.quant-gas</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1038/s41467-021-23159-z">10.1038/s41467-021-23159-z <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Ultrastrong Magnon-Magnon Coupling Dominated by Antiresonant Interactions </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Makihara%2C+T">Takuma Makihara</a>, <a href="/search/cond-mat?searchtype=author&query=Hayashida%2C+K">Kenji Hayashida</a>, <a href="/search/cond-mat?searchtype=author&query=Noe%2C+G+T">G. Timothy Noe II</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+X">Xinwei Li</a>, <a href="/search/cond-mat?searchtype=author&query=Peraca%2C+N+M">Nicolas Marquez Peraca</a>, <a href="/search/cond-mat?searchtype=author&query=Ma%2C+X">Xiaoxuan Ma</a>, <a href="/search/cond-mat?searchtype=author&query=Jin%2C+Z">Zuanming Jin</a>, <a href="/search/cond-mat?searchtype=author&query=Ren%2C+W">Wei Ren</a>, <a href="/search/cond-mat?searchtype=author&query=Ma%2C+G">Guohong Ma</a>, <a href="/search/cond-mat?searchtype=author&query=Katayama%2C+I">Ikufumi Katayama</a>, <a href="/search/cond-mat?searchtype=author&query=Takeda%2C+J">Jun Takeda</a>, <a href="/search/cond-mat?searchtype=author&query=Nojiri%2C+H">Hiroyuki Nojiri</a>, <a href="/search/cond-mat?searchtype=author&query=Turchinovich%2C+D">Dmitry Turchinovich</a>, <a href="/search/cond-mat?searchtype=author&query=Cao%2C+S">Shixun Cao</a>, <a href="/search/cond-mat?searchtype=author&query=Bamba%2C+M">Motoaki Bamba</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2008.10721v2-abstract-short" style="display: inline;"> Exotic quantum vacuum phenomena are predicted in cavity quantum electrodynamics (QED) systems with ultrastrong light-matter interactions. Their ground states are predicted to be vacuum squeezed states with suppressed quantum fluctuations. The source of such phenomena are antiresonant terms in the Hamiltonian, yet antiresonant interactions are typically negligible compared to resonant interactions… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2008.10721v2-abstract-full').style.display = 'inline'; document.getElementById('2008.10721v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2008.10721v2-abstract-full" style="display: none;"> Exotic quantum vacuum phenomena are predicted in cavity quantum electrodynamics (QED) systems with ultrastrong light-matter interactions. Their ground states are predicted to be vacuum squeezed states with suppressed quantum fluctuations. The source of such phenomena are antiresonant terms in the Hamiltonian, yet antiresonant interactions are typically negligible compared to resonant interactions in light-matter systems. We report an unusual coupled matter-matter system of magnons that can simulate a unique cavity QED Hamiltonian with coupling strengths that are easily tunable into the ultrastrong coupling regime and with dominant antiresonant terms. We found a novel regime where vacuum Bloch-Siegert shifts, the hallmark of antiresonant interactions, greatly exceed analogous frequency shifts from resonant interactions. Further, we theoretically explored the system's ground state and calculated up to 5.9 dB of quantum fluctuation suppression. These observations demonstrate that magnonic systems provide an ideal platform for simulating exotic quantum vacuum phenomena predicted in ultrastrongly coupled light-matter systems. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2008.10721v2-abstract-full').style.display = 'none'; document.getElementById('2008.10721v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 7 February, 2021; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 24 August, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2020. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">36 pages, 4 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2007.13263">arXiv:2007.13263</a> <span> [<a href="https://arxiv.org/pdf/2007.13263">pdf</a>, <a href="https://arxiv.org/ps/2007.13263">ps</a>, <a href="https://arxiv.org/format/2007.13263">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1038/s42005-021-00785-z">10.1038/s42005-021-00785-z <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Magnonic Superradiant Phase Transition </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Bamba%2C+M">Motoaki Bamba</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+X">Xinwei Li</a>, <a href="/search/cond-mat?searchtype=author&query=Peraca%2C+N+M">Nicolas Marquez Peraca</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2007.13263v1-abstract-short" style="display: inline;"> We show that the low-temperature phase transition in ErFeO3 that occurs at a critical temperature of ~ 4 K can be described as a magnonic version of the superradiant phase transition (SRPT). The role of photons in the quantum-optical SRPT is played by Fe magnons, while that of two-level atoms is played by Er spins. Our spin model, which is reduced to an extended Dicke model, takes into account the… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2007.13263v1-abstract-full').style.display = 'inline'; document.getElementById('2007.13263v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2007.13263v1-abstract-full" style="display: none;"> We show that the low-temperature phase transition in ErFeO3 that occurs at a critical temperature of ~ 4 K can be described as a magnonic version of the superradiant phase transition (SRPT). The role of photons in the quantum-optical SRPT is played by Fe magnons, while that of two-level atoms is played by Er spins. Our spin model, which is reduced to an extended Dicke model, takes into account the short-range, direct exchange interactions between Er spins in addition to the long-range Er-Er interactions mediated by Fe magnons. By using realistic parameters determined by recent terahertz magnetospectroscopy and magnetization experiments, we demonstrate that it is the cooperative, ultrastrong coupling between Er spins and Fe magnons that causes the phase transition. This work thus proves ErFeO3 to be a unique system that exhibits a SRPT in thermal equilibrium, in contrast to previous observations of laser-driven non-equilibrium SRPTs. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2007.13263v1-abstract-full').style.display = 'none'; document.getElementById('2007.13263v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 26 July, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2020. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">24 pages, 9 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Communications Physics 5, 3 (2022) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2004.11459">arXiv:2004.11459</a> <span> [<a href="https://arxiv.org/pdf/2004.11459">pdf</a>, <a href="https://arxiv.org/format/2004.11459">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Quantum Gases">cond-mat.quant-gas</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevLett.125.167401">10.1103/PhysRevLett.125.167401 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Observation of Photoinduced Terahertz Gain in GaAs Quantum Wells: Evidence for Radiative Two-Exciton-to-Biexciton Scattering </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Li%2C+X">X. Li</a>, <a href="/search/cond-mat?searchtype=author&query=Yoshioka%2C+K">K. Yoshioka</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+Q">Q. Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Peraca%2C+N+M">N. Marquez Peraca</a>, <a href="/search/cond-mat?searchtype=author&query=Katsutani%2C+F">F. Katsutani</a>, <a href="/search/cond-mat?searchtype=author&query=Gao%2C+W">W. Gao</a>, <a href="/search/cond-mat?searchtype=author&query=Noe%2C+G+T">G. T. Noe II</a>, <a href="/search/cond-mat?searchtype=author&query=Watson%2C+J+D">J. D. Watson</a>, <a href="/search/cond-mat?searchtype=author&query=Manfra%2C+M+J">M. J. Manfra</a>, <a href="/search/cond-mat?searchtype=author&query=Katayama%2C+I">I. Katayama</a>, <a href="/search/cond-mat?searchtype=author&query=Takeda%2C+J">J. Takeda</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">J. Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2004.11459v2-abstract-short" style="display: inline;"> We have observed photoinduced negative optical conductivity, or gain, in the terahertz frequency range in a GaAs multiple-quantum-well structure in a strong perpendicular magnetic field at low temperatures. The gain is narrow-band: it appears as a sharp peak (linewidth $<$0.45 meV) whose frequency shifts with applied magnetic field. The gain has a circular-polarization selection rule: a strong lin… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2004.11459v2-abstract-full').style.display = 'inline'; document.getElementById('2004.11459v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2004.11459v2-abstract-full" style="display: none;"> We have observed photoinduced negative optical conductivity, or gain, in the terahertz frequency range in a GaAs multiple-quantum-well structure in a strong perpendicular magnetic field at low temperatures. The gain is narrow-band: it appears as a sharp peak (linewidth $<$0.45 meV) whose frequency shifts with applied magnetic field. The gain has a circular-polarization selection rule: a strong line is observed for hole-cyclotron-resonance-active polarization. Furthermore, the gain appears only when the exciton $1s$ state is populated, which rules out intraexcitonic transitions to be its origin. Based on these observations, we propose a possible process in which the stimulated emission of a terahertz photon occurs while two free excitons scatter into one biexciton in an energy and angular-momentum conserving manner. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2004.11459v2-abstract-full').style.display = 'none'; document.getElementById('2004.11459v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 19 September, 2020; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 18 April, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2020. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">5 pages, 4 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Lett. 125, 167401 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2004.02615">arXiv:2004.02615</a> <span> [<a href="https://arxiv.org/pdf/2004.02615">pdf</a>, <a href="https://arxiv.org/format/2004.02615">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1021/acs.nanolett.9b05082">10.1021/acs.nanolett.9b05082 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Terahertz Excitonics in Carbon Nanotubes: Exciton Autoionization and Multiplication </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Bagsican%2C+F+R+G">Filchito Renee G. Bagsican</a>, <a href="/search/cond-mat?searchtype=author&query=Wais%2C+M">Michael Wais</a>, <a href="/search/cond-mat?searchtype=author&query=Komatsu%2C+N">Natsumi Komatsu</a>, <a href="/search/cond-mat?searchtype=author&query=Gao%2C+W">Weilu Gao</a>, <a href="/search/cond-mat?searchtype=author&query=Weber%2C+L+W">Lincoln W. Weber</a>, <a href="/search/cond-mat?searchtype=author&query=Serita%2C+K">Kazunori Serita</a>, <a href="/search/cond-mat?searchtype=author&query=Murakami%2C+H">Hironaru Murakami</a>, <a href="/search/cond-mat?searchtype=author&query=Held%2C+K">Karsten Held</a>, <a href="/search/cond-mat?searchtype=author&query=Hegmann%2C+F+A">Frank A. Hegmann</a>, <a href="/search/cond-mat?searchtype=author&query=Tonouchi%2C+M">Masayoshi Tonouchi</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Kawayama%2C+I">Iwao Kawayama</a>, <a href="/search/cond-mat?searchtype=author&query=Battiato%2C+M">Marco Battiato</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2004.02615v1-abstract-short" style="display: inline;"> Excitons play major roles in optical processes in modern semiconductors, such as single-wall carbon nanotubes (SWCNTs), transition metal dichalcogenides, and 2D perovskite quantum wells. They possess extremely large binding energies (>100~meV), dominating absorption and emission spectra even at high temperatures. The large binding energies imply that they are stable, that is, hard to ionize, rende… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2004.02615v1-abstract-full').style.display = 'inline'; document.getElementById('2004.02615v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2004.02615v1-abstract-full" style="display: none;"> Excitons play major roles in optical processes in modern semiconductors, such as single-wall carbon nanotubes (SWCNTs), transition metal dichalcogenides, and 2D perovskite quantum wells. They possess extremely large binding energies (>100~meV), dominating absorption and emission spectra even at high temperatures. The large binding energies imply that they are stable, that is, hard to ionize, rendering them seemingly unsuited for optoelectronic devices that require mobile charge carriers, especially terahertz emitters and solar cells. Here, we have conducted terahertz emission and photocurrent studies on films of aligned single-chirality semiconducting SWCNTs and find that excitons autoionize, i.e., spontaneously dissociate into electrons and holes. This process naturally occurs ultrafast (<1~ps) while conserving energy and momentum. The created carriers can then be accelerated to emit a burst of terahertz radiation when a dc bias is applied, with promising efficiency in comparison to standard GaAs-based emitters. Furthermore, at high bias, the accelerated carriers acquire high enough kinetic energy to create secondary excitons through impact exciton generation, again in a fully energy and momentum conserving fashion. This exciton multiplication process leads to a nonlinear photocurrent increase as a function of bias. Our theoretical simulations based on nonequilibrium Boltzmann transport equations, taking into account all possible scattering pathways and a realistic band structure, reproduce all our experimental data semi-quantitatively. These results not only elucidate the momentum-dependent ultrafast dynamics of excitons and carriers in SWCNTs but also suggest promising routes toward terahertz excitonics despite the orders-of-magnitude mismatch between the exciton binding energies and the terahertz photon energies. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2004.02615v1-abstract-full').style.display = 'none'; document.getElementById('2004.02615v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 6 April, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2020. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1912.11175">arXiv:1912.11175</a> <span> [<a href="https://arxiv.org/pdf/1912.11175">pdf</a>, <a href="https://arxiv.org/format/1912.11175">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1021/acs.nanolett.9b04764">10.1021/acs.nanolett.9b04764 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Groove-Assisted Global Spontaneous Alignment of Carbon Nanotubes in Vacuum Filtration </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Komatsu%2C+N">Natsumi Komatsu</a>, <a href="/search/cond-mat?searchtype=author&query=Nakamura%2C+M">Motonori Nakamura</a>, <a href="/search/cond-mat?searchtype=author&query=Ghosh%2C+S">Saunab Ghosh</a>, <a href="/search/cond-mat?searchtype=author&query=Kim%2C+D">Daeun Kim</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+H">Haoze Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Katagiri%2C+A">Atsuhiro Katagiri</a>, <a href="/search/cond-mat?searchtype=author&query=Yomogida%2C+Y">Yohei Yomogida</a>, <a href="/search/cond-mat?searchtype=author&query=Gao%2C+W">Weilu Gao</a>, <a href="/search/cond-mat?searchtype=author&query=Yanagi%2C+K">Kazuhiro Yanagi</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1912.11175v1-abstract-short" style="display: inline;"> Ever since the discovery of carbon nanotubes (CNTs), it has long been a challenging goal to create macroscopically ordered assemblies, or crystals, of CNTs that preserve the one-dimensional quantum properties of individual CNTs on a macroscopic scale. Recently, a simple and well-controlled method was reported for producing wafer-scale crystalline films of highly aligned and densely packed CNTs thr… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1912.11175v1-abstract-full').style.display = 'inline'; document.getElementById('1912.11175v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1912.11175v1-abstract-full" style="display: none;"> Ever since the discovery of carbon nanotubes (CNTs), it has long been a challenging goal to create macroscopically ordered assemblies, or crystals, of CNTs that preserve the one-dimensional quantum properties of individual CNTs on a macroscopic scale. Recently, a simple and well-controlled method was reported for producing wafer-scale crystalline films of highly aligned and densely packed CNTs through spontaneous global alignment that occurs during vacuum filtration [\textit{Nat.\ Nanotechnol}.\ \textbf{11}, 633 (2016)]. However, a full understanding of the mechanism of such global alignment has not been achieved. Here, we report results of a series of systematic experiments that demonstrate that the CNT alignment direction can be controlled by the surface morphology of the filter membrane used in the vacuum filtration process. More specifically, we found that the direction of parallel grooves pre-existing on the surface of the filter membrane dictates the direction of the resulting CNT alignment. Furthermore, we intentionally imprinted periodically spaced parallel grooves on a filter membranes using a diffraction grating, which successfully defined the direction of the global alignment of CNTs in a precise and reproducible manner. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1912.11175v1-abstract-full').style.display = 'none'; document.getElementById('1912.11175v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 23 December, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">18 pages, 5 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Nano Letters 20, 2332 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1907.00137">arXiv:1907.00137</a> <span> [<a href="https://arxiv.org/pdf/1907.00137">pdf</a>, <a href="https://arxiv.org/format/1907.00137">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevB.100.115145">10.1103/PhysRevB.100.115145 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Terahertz Faraday and Kerr rotation spectroscopy of Bi$_{1-x}$Sb$_x$ films in high magnetic fields up to 30 Tesla </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Li%2C+X">Xinwei Li</a>, <a href="/search/cond-mat?searchtype=author&query=Yoshioka%2C+K">Katsumasa Yoshioka</a>, <a href="/search/cond-mat?searchtype=author&query=Xie%2C+M">Ming Xie</a>, <a href="/search/cond-mat?searchtype=author&query=Noe%2C+G+T">G. Timothy Noe II</a>, <a href="/search/cond-mat?searchtype=author&query=Lee%2C+W">Woojoo Lee</a>, <a href="/search/cond-mat?searchtype=author&query=Peraca%2C+N+M">Nicolas Marquez Peraca</a>, <a href="/search/cond-mat?searchtype=author&query=Gao%2C+W">Weilu Gao</a>, <a href="/search/cond-mat?searchtype=author&query=Hagiwara%2C+T">Toshio Hagiwara</a>, <a href="/search/cond-mat?searchtype=author&query=Orjan%2C+H+S">Handegard S. Orjan</a>, <a href="/search/cond-mat?searchtype=author&query=Nien%2C+L">Li-Wei Nien</a>, <a href="/search/cond-mat?searchtype=author&query=Nagao%2C+T">Tadaaki Nagao</a>, <a href="/search/cond-mat?searchtype=author&query=Kitajima%2C+M">Masahiro Kitajima</a>, <a href="/search/cond-mat?searchtype=author&query=Nojiri%2C+H">Hiroyuki Nojiri</a>, <a href="/search/cond-mat?searchtype=author&query=Shih%2C+C">Chih-Kang Shih</a>, <a href="/search/cond-mat?searchtype=author&query=MacDonald%2C+A+H">Allan H. MacDonald</a>, <a href="/search/cond-mat?searchtype=author&query=Katayama%2C+I">Ikufumi Katayama</a>, <a href="/search/cond-mat?searchtype=author&query=Takeda%2C+J">Jun Takeda</a>, <a href="/search/cond-mat?searchtype=author&query=Fiete%2C+G+A">Gregory A. Fiete</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1907.00137v1-abstract-short" style="display: inline;"> We report results of terahertz Faraday and Kerr rotation spectroscopy measurements on thin films of $\text{Bi}_{1-x}\text{Sb}_{x}$, an alloy system that exhibits a semimetal-to-topological-insulator transition as the Sb composition $x$ increases. By using a single-shot time-domain terahertz spectroscopy setup combined with a table-top pulsed mini-coil magnet, we conducted measurements in magnetic… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1907.00137v1-abstract-full').style.display = 'inline'; document.getElementById('1907.00137v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1907.00137v1-abstract-full" style="display: none;"> We report results of terahertz Faraday and Kerr rotation spectroscopy measurements on thin films of $\text{Bi}_{1-x}\text{Sb}_{x}$, an alloy system that exhibits a semimetal-to-topological-insulator transition as the Sb composition $x$ increases. By using a single-shot time-domain terahertz spectroscopy setup combined with a table-top pulsed mini-coil magnet, we conducted measurements in magnetic fields up to 30~T, observing distinctly different behaviors between semimetallic ($x < 0.07$) and topological insulator ($x > 0.07$) samples. Faraday and Kerr rotation spectra for the semimetallic films showed a pronounced dip that blue-shifted with the magnetic field, whereas spectra for the topological insulator films were positive and featureless, increasing in amplitude with increasing magnetic field and eventually saturating at high fields ($>$20~T). Ellipticity spectra for the semimetallic films showed resonances, whereas the topological insulator films showed no detectable ellipticity. To explain these observations, we developed a theoretical model based on realistic band parameters and the Kubo formula for calculating the optical conductivity of Landau-quantized charge carriers. Our calculations quantitatively reproduced all experimental features, establishing that the Faraday and Kerr signals in the semimetallic films predominantly arise from bulk hole cyclotron resonances while the signals in the topological insulator films represent combined effects of surface carriers originating from multiple electron and hole pockets. These results demonstrate that the use of high magnetic fields in terahertz magnetopolarimetry, combined with detailed electronic structure and conductivity calculations, allows us to unambiguously identify and quantitatively determine unique contributions from different species of carriers of topological and nontopological nature in Bi$_{1-x}$Sb$_x$. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1907.00137v1-abstract-full').style.display = 'none'; document.getElementById('1907.00137v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 28 June, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">17 pages, 22 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 100, 115145 (2019) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1903.06063">arXiv:1903.06063</a> <span> [<a href="https://arxiv.org/pdf/1903.06063">pdf</a>, <a href="https://arxiv.org/format/1903.06063">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1021/acsphotonics.9b00452">10.1021/acsphotonics.9b00452 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Macroscopically Aligned Carbon Nanotubes as a Refractory Platform for Hyperbolic Thermal Emitters </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Gao%2C+W">Weilu Gao</a>, <a href="/search/cond-mat?searchtype=author&query=Doiron%2C+C+F">Chloe F. Doiron</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+X">Xinwei Li</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Naik%2C+G+V">Gururaj V. Naik</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1903.06063v1-abstract-short" style="display: inline;"> Refractory nanophotonics, or nanophotonics at high temperatures, can revolutionize many applications, including data storage and waste heat recovery. In particular, nanophotonic devices made from hyperbolic materials are promising due to their nearly infinite photonic density of states (PDOS). However, it is challenging to achieve a prominent PDOS in existing refractory hyperbolic materials, espec… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1903.06063v1-abstract-full').style.display = 'inline'; document.getElementById('1903.06063v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1903.06063v1-abstract-full" style="display: none;"> Refractory nanophotonics, or nanophotonics at high temperatures, can revolutionize many applications, including data storage and waste heat recovery. In particular, nanophotonic devices made from hyperbolic materials are promising due to their nearly infinite photonic density of states (PDOS). However, it is challenging to achieve a prominent PDOS in existing refractory hyperbolic materials, especially in a broad spectral range. Here, we demonstrate that macroscopic films and architectures of aligned carbon nanotubes work as excellent refractory hyperbolic materials. We found that aligned carbon nanotubes are thermally stable up to $1600^{\circ}$C and exhibit extreme anisotropy - metallic in one direction and insulating in the other two directions. Such extreme anisotropy makes this system a hyperbolic material with an exceptionally large PDOS over a broadband spectrum range (longer than $4.3渭$m) in the midinfrared, exhibiting strong resonances in deeply sub-wavelength-sized cavities. We observed polarized, spectrally selective thermal emission from aligned carbon nanotube films as well as indefinite cavities of aligned carbon nanotubes with volume as small as $\sim位^3/700$ operating at $700^{\circ}$C . These experiments suggest that aligned carbon nanotubes possess naturally large PDOS that leads to thermal photon densities enhanced by over two orders of magnitude, making them a promising refractory nanophotonics platform. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1903.06063v1-abstract-full').style.display = 'none'; document.getElementById('1903.06063v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 14 March, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">12 pages, 8 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> ACS Photonics 2019, 6, 7, 1602-1609 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1901.06749">arXiv:1901.06749</a> <span> [<a href="https://arxiv.org/pdf/1901.06749">pdf</a>, <a href="https://arxiv.org/format/1901.06749">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1117/12.2512794">10.1117/12.2512794 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Terahertz Strong-Field Physics without a Strong External Terahertz Field </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Bamba%2C+M">Motoaki Bamba</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+X">Xinwei Li</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1901.06749v1-abstract-short" style="display: inline;"> Traditionally, strong-field physics explores phenomena in matter (atoms, molecules, and solids) driven by an extremely strong laser field nonperturbatively. However, even in the complete absence of an external electromagnetic field, strong-field phenomena can arise when matter strongly couples with the zero-point field of the quantum vacuum state, i.e., fluctuating electromagnetic waves whose expe… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1901.06749v1-abstract-full').style.display = 'inline'; document.getElementById('1901.06749v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1901.06749v1-abstract-full" style="display: none;"> Traditionally, strong-field physics explores phenomena in matter (atoms, molecules, and solids) driven by an extremely strong laser field nonperturbatively. However, even in the complete absence of an external electromagnetic field, strong-field phenomena can arise when matter strongly couples with the zero-point field of the quantum vacuum state, i.e., fluctuating electromagnetic waves whose expectation value is zero. Some of the most striking examples of this occur in a cavity setting, in which an ensemble of two-level atoms resonantly interacts with a single photonic mode of vacuum fields, producing vacuum Rabi splitting. In particular, the nature of the matter-vacuum-field coupled system fundamentally changes when the coupling rate (equal to one half of the vacuum Rabi splitting) becomes comparable to, or larger than, the resonance frequency. In this so-called ultrastrong coupling regime, a non-negligible number of photons exist in the ground state of the coupled system. Furthermore, the coupling rate can be cooperatively enhanced (via so-called Dicke cooperativity) when the matter is comprised of a large number of identical two-level particles, and a quantum phase transition is predicted to occur as the coupling rate reaches a critical value. Low-energy electronic or magnetic transitions in many-body condensed matter systems with large dipole moments are ideally suited for searching for these predicted phenomena. Here, we discuss two condensed matter systems that have shown cooperative ultrastrong interactions in the terahertz frequency range: a Landau-quantized two-dimensional electron gas interacting with high-quality-factor cavity photons, and an Er$^{3+}$ spin ensemble interacting with Fe$^{3+}$ magnons in ErFeO$_3$. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1901.06749v1-abstract-full').style.display = 'none'; document.getElementById('1901.06749v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 20 January, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">12 pages, 4 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Proc. SPIE 10916, Ultrafast Phenomena and Nanophotonics XXIII, 1091605 (2019) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1810.02928">arXiv:1810.02928</a> <span> [<a href="https://arxiv.org/pdf/1810.02928">pdf</a>, <a href="https://arxiv.org/format/1810.02928">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1098/rsos.181605">10.1098/rsos.181605 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Science and applications of wafer-scale crystalline carbon nanotube films prepared through controlled vacuum filtration </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Gao%2C+W">Weilu Gao</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1810.02928v1-abstract-short" style="display: inline;"> Carbon nanotubes (CNTs) make an ideal one-dimensional (1D) material platform for the exploration of exotic physical phenomena under extremely strong quantum confinement. The 1D character of electrons, phonons and excitons in individual CNTs features extraordinary electronic, thermal and optical properties. Since the first discovery, they have been continuing to attract interest in various discipli… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1810.02928v1-abstract-full').style.display = 'inline'; document.getElementById('1810.02928v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1810.02928v1-abstract-full" style="display: none;"> Carbon nanotubes (CNTs) make an ideal one-dimensional (1D) material platform for the exploration of exotic physical phenomena under extremely strong quantum confinement. The 1D character of electrons, phonons and excitons in individual CNTs features extraordinary electronic, thermal and optical properties. Since the first discovery, they have been continuing to attract interest in various disciplines, including chemistry, materials science, physics, and engineering. However, the macroscopic manifestation of such properties is still limited, despite significant efforts for decades. Recently, a controlled vacuum filtration method has been developed for the preparation of wafer-scale films of crystalline chirality-enriched CNTs, and such films immediately enable exciting new fundamental studies and applications. In this review, we will first discuss the controlled vacuum filtration technique, and then summarize recent discoveries in optical spectroscopy studies and optoelectronic device applications using films prepared by this technique. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1810.02928v1-abstract-full').style.display = 'none'; document.getElementById('1810.02928v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 5 October, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">24 pages, 14 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Royal Society Open Science 6, 181605 (2019) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1808.08602">arXiv:1808.08602</a> <span> [<a href="https://arxiv.org/pdf/1808.08602">pdf</a>, <a href="https://arxiv.org/format/1808.08602">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevB.99.035426">10.1103/PhysRevB.99.035426 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Direct Observation of Cross-Polarized Excitons in Aligned Single-Chirality Single-Wall Carbon Nanotubes </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Katsutani%2C+F">Fumiya Katsutani</a>, <a href="/search/cond-mat?searchtype=author&query=Gao%2C+W">Weilu Gao</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+X">Xinwei Li</a>, <a href="/search/cond-mat?searchtype=author&query=Ichinose%2C+Y">Yota Ichinose</a>, <a href="/search/cond-mat?searchtype=author&query=Yomogida%2C+Y">Yohei Yomogida</a>, <a href="/search/cond-mat?searchtype=author&query=Yanagi%2C+K">Kazuhiro Yanagi</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1808.08602v1-abstract-short" style="display: inline;"> Optical properties of single-wall carbon nanotubes (SWCNTs) for light polarized parallel to the nanotube axis have been extensively studied, whereas their response to light polarized perpendicular to the nanotube axis has not been well explored. Here, by using a macroscopic film of highly aligned single-chirality (6,5) SWCNTs, we performed a systematic polarization-dependent optical absorption spe… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.08602v1-abstract-full').style.display = 'inline'; document.getElementById('1808.08602v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1808.08602v1-abstract-full" style="display: none;"> Optical properties of single-wall carbon nanotubes (SWCNTs) for light polarized parallel to the nanotube axis have been extensively studied, whereas their response to light polarized perpendicular to the nanotube axis has not been well explored. Here, by using a macroscopic film of highly aligned single-chirality (6,5) SWCNTs, we performed a systematic polarization-dependent optical absorption spectroscopy study. In addition to the commonly observed angular-momentum-conserving interband absorption of parallel-polarized light, which generates $E_{11}$ and $E_{22}$ excitons, we observed a small but unambiguous absorption peak whose intensity is maximum for perpendicular-polarized light. We attribute this feature to the lowest-energy cross-polarized interband absorption processes that change the angular momentum along the nanotube axis by $\pm 1$, generating $E_{12}$ and $E_{21}$ excitons. The energy difference between the $E_{12}$ and $E_{21}$ exciton peaks, expected from asymmetry between the conduction and valence bands, was smaller than the observed linewidth. Unlike previous observations of cross-polarized excitons in polarization-dependent photoluminescence and circular dichroism spectroscopy experiments, our direct observation using absorption spectroscopy allowed us to quantitatively analyze this resonance. Specifically, we determined the energy and oscillator strength of this resonance to be 1.54 and 0.05, respectively, compared with the values for the $E_{11}$ exciton peak. These values, in combination with comparison with theoretical calculations, in turn led to an assessment of the environmental effect on the strength of Coulomb interactions in this aligned single-chirality SWCNT film. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.08602v1-abstract-full').style.display = 'none'; document.getElementById('1808.08602v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 26 August, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">14 pages, 14 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 99, 035426 (2019) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1808.02296">arXiv:1808.02296</a> <span> [<a href="https://arxiv.org/pdf/1808.02296">pdf</a>, <a href="https://arxiv.org/format/1808.02296">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Strongly Correlated Electrons">cond-mat.str-el</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1126/science.aag1595">10.1126/science.aag1595 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Singular charge fluctuations at a magnetic quantum critical point </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Prochaska%2C+L">L. Prochaska</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+X">X. Li</a>, <a href="/search/cond-mat?searchtype=author&query=MacFarland%2C+D+C">D. C. MacFarland</a>, <a href="/search/cond-mat?searchtype=author&query=Andrews%2C+A+M">A. M. Andrews</a>, <a href="/search/cond-mat?searchtype=author&query=Bonta%2C+M">M. Bonta</a>, <a href="/search/cond-mat?searchtype=author&query=Bianco%2C+E+F">E. F. Bianco</a>, <a href="/search/cond-mat?searchtype=author&query=Yazdi%2C+S">S. Yazdi</a>, <a href="/search/cond-mat?searchtype=author&query=Schrenk%2C+W">W. Schrenk</a>, <a href="/search/cond-mat?searchtype=author&query=Detz%2C+H">H. Detz</a>, <a href="/search/cond-mat?searchtype=author&query=Limbeck%2C+A">A. Limbeck</a>, <a href="/search/cond-mat?searchtype=author&query=Si%2C+Q">Q. Si</a>, <a href="/search/cond-mat?searchtype=author&query=Ringe%2C+E">E. Ringe</a>, <a href="/search/cond-mat?searchtype=author&query=Strasser%2C+G">G. Strasser</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">J. Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Paschen%2C+S">S. Paschen</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1808.02296v1-abstract-short" style="display: inline;"> Strange metal behavior is ubiquitous to correlated materials ranging from cuprate superconductors to bilayer graphene. There is increasing recognition that it arises from physics beyond the quantum fluctuations of a Landau order parameter which, in quantum critical heavy fermion antiferromagnets, may be realized as critical Kondo entanglement of spin and charge. The dynamics of the associated elec… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.02296v1-abstract-full').style.display = 'inline'; document.getElementById('1808.02296v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1808.02296v1-abstract-full" style="display: none;"> Strange metal behavior is ubiquitous to correlated materials ranging from cuprate superconductors to bilayer graphene. There is increasing recognition that it arises from physics beyond the quantum fluctuations of a Landau order parameter which, in quantum critical heavy fermion antiferromagnets, may be realized as critical Kondo entanglement of spin and charge. The dynamics of the associated electronic delocalization transition could be ideally probed by optical conductivity, but experiments in the corresponding frequency and temperature ranges have remained elusive. We present terahertz time-domain transmission spectroscopy on molecular beam epitaxy-grown thin films of YbRh$_2$Si$_2$, a model strange metal compound. We observe frequency over temperature scaling of the optical conductivity as a hallmark of beyond-Landau quantum criticality. Our discovery implicates critical charge fluctuations as playing a central role in the strange metal behavior, thereby elucidating one of the longstanding mysteries of correlated quantum matter. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.02296v1-abstract-full').style.display = 'none'; document.getElementById('1808.02296v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 7 August, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">preprint with 15 pages, 4 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Science 367 (2020) 285-288 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1804.09275">arXiv:1804.09275</a> <span> [<a href="https://arxiv.org/pdf/1804.09275">pdf</a>, <a href="https://arxiv.org/format/1804.09275">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Physics">quant-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Superconductivity">cond-mat.supr-con</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/RevModPhys.91.025005">10.1103/RevModPhys.91.025005 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Ultrastrong coupling regimes of light-matter interaction </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Forn-D%C3%ADaz%2C+P">P. Forn-D铆az</a>, <a href="/search/cond-mat?searchtype=author&query=Lamata%2C+L">L. Lamata</a>, <a href="/search/cond-mat?searchtype=author&query=Rico%2C+E">E. Rico</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">J. Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Solano%2C+E">E. Solano</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1804.09275v3-abstract-short" style="display: inline;"> Recent experiments have demonstrated that light and matter can mix together to an extreme degree, and previously uncharted regimes of light-matter interactions are currently being explored in a variety of settings. The so-called ultrastrong coupling (USC) regime is established when the light-matter interaction energy is a comparable fraction of the bare frequencies of the uncoupled systems. Furthe… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1804.09275v3-abstract-full').style.display = 'inline'; document.getElementById('1804.09275v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1804.09275v3-abstract-full" style="display: none;"> Recent experiments have demonstrated that light and matter can mix together to an extreme degree, and previously uncharted regimes of light-matter interactions are currently being explored in a variety of settings. The so-called ultrastrong coupling (USC) regime is established when the light-matter interaction energy is a comparable fraction of the bare frequencies of the uncoupled systems. Furthermore, when the interaction strengths become larger than the bare frequencies, the deep-strong coupling (DSC) regime emerges. This article reviews advances in the field of the USC and DSC regimes, in particular, for light modes confined in cavities interacting with two-level systems. An overview is first provided on the theoretical progress since the origins from the semiclassical Rabi model until recent developments of the quantum Rabi model. Next, several key experimental results from a variety of quantum platforms are described, including superconducting circuits, semiconductor quantum wells, and other hybrid quantum systems. Finally, anticipated applications are highlighted utilizing USC and DSC regimes, including novel quantum optical phenomena, quantum simulation, and quantum computation. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1804.09275v3-abstract-full').style.display = 'none'; document.getElementById('1804.09275v3-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 12 June, 2019; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 24 April, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Review article, 53 pages, 39 figures. Published version</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Rev. Mod. Phys. 91, 25005 (2019) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1709.00123">arXiv:1709.00123</a> <span> [<a href="https://arxiv.org/pdf/1709.00123">pdf</a>, <a href="https://arxiv.org/format/1709.00123">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevLett.120.057405">10.1103/PhysRevLett.120.057405 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Magneto-Optics of Exciton Rydberg States in a Monolayer Semiconductor </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Stier%2C+A+V">Andreas V. Stier</a>, <a href="/search/cond-mat?searchtype=author&query=Wilson%2C+N+P">Nathan P. Wilson</a>, <a href="/search/cond-mat?searchtype=author&query=Velizhanin%2C+K+A">Kirill A. Velizhanin</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+X">Xiaodong Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Crooker%2C+S+A">Scott A. Crooker</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1709.00123v2-abstract-short" style="display: inline;"> We report 65 tesla magneto-absorption spectroscopy of exciton Rydberg states in the archetypal monolayer semiconductor WSe$_2$. The strongly field-dependent and distinct energy shifts of the 2s, 3s, and 4s excited neutral excitons permits their unambiguous identification and allows for quantitative comparison with leading theoretical models. Both the sizes (via low-field diamagnetic shifts) and th… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1709.00123v2-abstract-full').style.display = 'inline'; document.getElementById('1709.00123v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1709.00123v2-abstract-full" style="display: none;"> We report 65 tesla magneto-absorption spectroscopy of exciton Rydberg states in the archetypal monolayer semiconductor WSe$_2$. The strongly field-dependent and distinct energy shifts of the 2s, 3s, and 4s excited neutral excitons permits their unambiguous identification and allows for quantitative comparison with leading theoretical models. Both the sizes (via low-field diamagnetic shifts) and the energies of the $ns$ exciton states agree remarkably well with detailed numerical simulations using the non-hydrogenic screened Keldysh potential for 2D semiconductors. Moreover, at the highest magnetic fields the nearly-linear diamagnetic shifts of the weakly-bound 3s and 4s excitons provide a direct experimental measure of the exciton's reduced mass, $m_r = 0.20 \pm 0.01~m_0$. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1709.00123v2-abstract-full').style.display = 'none'; document.getElementById('1709.00123v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 25 January, 2018; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 31 August, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">To appear in Phys. Rev. Lett. Updated version (25 jan 2018) now includes detailed supplemental discussion of Landau levels, Rydberg exciton energies, exciton mass, Dirac Hamiltonian, nonparabolicity, and dielectric effects</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Lett. 120, 057405 (2018) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1610.05784">arXiv:1610.05784</a> <span> [<a href="https://arxiv.org/pdf/1610.05784">pdf</a>, <a href="https://arxiv.org/format/1610.05784">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevB.95.045116">10.1103/PhysRevB.95.045116 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Probing the semiconductor to semimetal transition in InAs/GaSb double quantum wells by magneto-infrared spectroscopy </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Jiang%2C+Y">Y. Jiang</a>, <a href="/search/cond-mat?searchtype=author&query=Thapa%2C+S">S. Thapa</a>, <a href="/search/cond-mat?searchtype=author&query=Sanders%2C+G+D">G. D. Sanders</a>, <a href="/search/cond-mat?searchtype=author&query=Stanton%2C+C+J">C. J. Stanton</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+Q">Q. Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">J. Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Lou%2C+W+K">W. K. Lou</a>, <a href="/search/cond-mat?searchtype=author&query=Chang%2C+K">K. Chang</a>, <a href="/search/cond-mat?searchtype=author&query=Hawkins%2C+S+D">S. D. Hawkins</a>, <a href="/search/cond-mat?searchtype=author&query=Klem%2C+J+F">J. F. Klem</a>, <a href="/search/cond-mat?searchtype=author&query=Pan%2C+W">W. Pan</a>, <a href="/search/cond-mat?searchtype=author&query=Smirnov%2C+D">D. Smirnov</a>, <a href="/search/cond-mat?searchtype=author&query=Jiang%2C+Z">Z. Jiang</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1610.05784v1-abstract-short" style="display: inline;"> We perform a magneto-infrared spectroscopy study of the semiconductor to semimetal transition of InAs/GaSb double quantum wells from the normal to the inverted state. We show that owing to the low carrier density of our samples (approaching the intrinsic limit), the magneto-absorption spectra evolve from a single cyclotron resonance peak in the normal state to multiple absorption peaks in the inve… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1610.05784v1-abstract-full').style.display = 'inline'; document.getElementById('1610.05784v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1610.05784v1-abstract-full" style="display: none;"> We perform a magneto-infrared spectroscopy study of the semiconductor to semimetal transition of InAs/GaSb double quantum wells from the normal to the inverted state. We show that owing to the low carrier density of our samples (approaching the intrinsic limit), the magneto-absorption spectra evolve from a single cyclotron resonance peak in the normal state to multiple absorption peaks in the inverted state with distinct magnetic field dependence. Using an eight-band Pidgeon-Brown model, we explain all the major absorption peaks observed in our experiment. We demonstrate that the semiconductor to semimetal transition can be realized by manipulating the quantum confinement, the strain, and the magnetic field. Our work paves the way for band engineering of optimal InAs/GaSb structures for realizing novel topological states as well as for device applications in the terahertz regime. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1610.05784v1-abstract-full').style.display = 'none'; document.getElementById('1610.05784v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 18 October, 2016; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2016. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">15 pages, 9 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 95, 045116 (2017) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1606.08278">arXiv:1606.08278</a> <span> [<a href="https://arxiv.org/pdf/1606.08278">pdf</a>, <a href="https://arxiv.org/format/1606.08278">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Gases">cond-mat.quant-gas</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevLett.117.207402">10.1103/PhysRevLett.117.207402 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Stability of High-Density Two-Dimensional Excitons against a Mott Transition in High Magnetic Fields Probed by Coherent Terahertz Spectroscopy </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+Q">Qi Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%2C+Y">Yongrui Wang</a>, <a href="/search/cond-mat?searchtype=author&query=Gao%2C+W">Weilu Gao</a>, <a href="/search/cond-mat?searchtype=author&query=Long%2C+Z">Zhongqu Long</a>, <a href="/search/cond-mat?searchtype=author&query=Watson%2C+J+D">John D. Watson</a>, <a href="/search/cond-mat?searchtype=author&query=Manfra%2C+M+J">Michael J. Manfra</a>, <a href="/search/cond-mat?searchtype=author&query=Belyanin%2C+A">Alexey Belyanin</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1606.08278v2-abstract-short" style="display: inline;"> We have performed time-resolved terahertz absorption measurements on photoexcited electron-hole pairs in undoped GaAs quantum wells in magnetic fields. We probed both unbound- and bound-carrier responses via cyclotron resonance and intraexciton resonance, respectively. The stability of excitons, monitored as the pair density was systematically increased, was found to dramatically increase with inc… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1606.08278v2-abstract-full').style.display = 'inline'; document.getElementById('1606.08278v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1606.08278v2-abstract-full" style="display: none;"> We have performed time-resolved terahertz absorption measurements on photoexcited electron-hole pairs in undoped GaAs quantum wells in magnetic fields. We probed both unbound- and bound-carrier responses via cyclotron resonance and intraexciton resonance, respectively. The stability of excitons, monitored as the pair density was systematically increased, was found to dramatically increase with increasing magnetic field. Specifically, the 1$s$-2$p_-$ intraexciton transition at 9 T persisted up to the highest density, whereas the 1$s$-2$p$ feature at 0 T was quickly replaced by a free-carrier Drude response. Interestingly, at 9 T, the 1$s$-2$p_-$ peak was replaced by free-hole cyclotron resonance at high temperatures, indicating that 2D magnetoexcitons do dissociate under thermal excitation, even though they are stable against a density-driven Mott transition. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1606.08278v2-abstract-full').style.display = 'none'; document.getElementById('1606.08278v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 12 October, 2016; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 27 June, 2016; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2016. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">5 pages, 4 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Physical Review Letters 117, 207402 (2016) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1604.08297">arXiv:1604.08297</a> <span> [<a href="https://arxiv.org/pdf/1604.08297">pdf</a>, <a href="https://arxiv.org/format/1604.08297">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Gases">cond-mat.quant-gas</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1038/nphys3850">10.1038/nphys3850 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Collective, Coherent, and Ultrastrong Coupling of 2D Electrons with Terahertz Cavity Photons </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+Q">Qi Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Lou%2C+M">Minhan Lou</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+X">Xinwei Li</a>, <a href="/search/cond-mat?searchtype=author&query=Reno%2C+J+L">John L. Reno</a>, <a href="/search/cond-mat?searchtype=author&query=Pan%2C+W">Wei Pan</a>, <a href="/search/cond-mat?searchtype=author&query=Watson%2C+J+D">John D. Watson</a>, <a href="/search/cond-mat?searchtype=author&query=Manfra%2C+M+J">Michael J. Manfra</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1604.08297v1-abstract-short" style="display: inline;"> Nonperturbative coupling of light with condensed matter in an optical cavity is expected to reveal a host of coherent many-body phenomena and states. In addition, strong coherent light-matter interaction in a solid-state environment is of great interest to emerging quantum-based technologies. However, creating a system that combines a long electronic coherence time, a large dipole moment, and a hi… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1604.08297v1-abstract-full').style.display = 'inline'; document.getElementById('1604.08297v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1604.08297v1-abstract-full" style="display: none;"> Nonperturbative coupling of light with condensed matter in an optical cavity is expected to reveal a host of coherent many-body phenomena and states. In addition, strong coherent light-matter interaction in a solid-state environment is of great interest to emerging quantum-based technologies. However, creating a system that combines a long electronic coherence time, a large dipole moment, and a high cavity quality ($Q$) factor has been a challenging goal. Here, we report collective ultrastrong light-matter coupling in an ultrahigh-mobility two-dimensional electron gas in a high-$Q$ terahertz photonic-crystal cavity in a quantizing magnetic field, demonstrating a cooperativity of $\sim$360. The splitting of cyclotron resonance (CR) into the lower and upper polariton branches exhibited a $\sqrt{n_\mathrm{e}}$-dependence on the electron density ($n_\mathrm{e}$), a hallmark of collective vacuum Rabi splitting. Furthermore, a small but definite blue shift was observed for the polariton frequencies due to the normally negligible $A^2$ term in the light-matter interaction Hamiltonian. Finally, the high-$Q$ cavity suppressed the superradiant decay of coherent CR, which resulted in an unprecedentedly narrow intrinsic CR linewidth of 5.6 GHz at 2 K. These results open up a variety of new possibilities to combine the traditional disciplines of many-body condensed matter physics and cavity-based quantum optics. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1604.08297v1-abstract-full').style.display = 'none'; document.getElementById('1604.08297v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 27 April, 2016; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2016. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">6 pages, 4 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Nature Physics 12, 1005 (2016) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1603.07004">arXiv:1603.07004</a> <span> [<a href="https://arxiv.org/pdf/1603.07004">pdf</a>, <a href="https://arxiv.org/format/1603.07004">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1116/1.4948992">10.1116/1.4948992 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Magneto-reflection spectroscopy of monolayer transition-metal dichalcogenide semiconductors in pulsed magnetic fields </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Stier%2C+A+V">Andreas V. Stier</a>, <a href="/search/cond-mat?searchtype=author&query=McCreary%2C+K+M">Kathleen M. McCreary</a>, <a href="/search/cond-mat?searchtype=author&query=Jonker%2C+B+T">Berend T. Jonker</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Crooker%2C+S+A">Scott A. Crooker</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1603.07004v1-abstract-short" style="display: inline;"> We describe recent experimental efforts to perform polarization-resolved optical spectroscopy of monolayer transition-metal dichalcogenide semiconductors in very large pulsed magnetic fields to 65 tesla. The experimental setup and technical challenges are discussed in detail, and temperature-dependent magneto-reflection spectra from atomically thin tungsten disulphide (WS$_2$) are presented. The d… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1603.07004v1-abstract-full').style.display = 'inline'; document.getElementById('1603.07004v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1603.07004v1-abstract-full" style="display: none;"> We describe recent experimental efforts to perform polarization-resolved optical spectroscopy of monolayer transition-metal dichalcogenide semiconductors in very large pulsed magnetic fields to 65 tesla. The experimental setup and technical challenges are discussed in detail, and temperature-dependent magneto-reflection spectra from atomically thin tungsten disulphide (WS$_2$) are presented. The data clearly reveal not only the valley Zeeman effect in these 2D semiconductors, but also the small quadratic exciton diamagnetic shift from which the very small exciton size can be directly inferred. Finally, we present model calculations that demonstrate how the measured diamagnetic shifts can be used to constrain estimates of the exciton binding energy in this new family of monolayer semiconductors. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1603.07004v1-abstract-full').style.display = 'none'; document.getElementById('1603.07004v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 22 March, 2016; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2016. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">PCSI-43 conference (Jan. 2016; Palm Springs, CA)</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> J. Vac. Sci. Tech. B 34, 04J102 (2016) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1602.04374">arXiv:1602.04374</a> <span> [<a href="https://arxiv.org/pdf/1602.04374">pdf</a>, <a href="https://arxiv.org/format/1602.04374">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Quantum Gases">cond-mat.quant-gas</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1364/JOSAB.33.000C80">10.1364/JOSAB.33.000C80 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Dicke Superradiance in Solids </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Cong%2C+K">Kankan Cong</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+Q">Qi Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%2C+Y">Yongrui Wang</a>, <a href="/search/cond-mat?searchtype=author&query=Noe%2C+G+T">G. Timothy Noe II</a>, <a href="/search/cond-mat?searchtype=author&query=Belyanin%2C+A">Alexey Belyanin</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1602.04374v2-abstract-short" style="display: inline;"> Recent advances in optical studies of condensed matter have led to the emergence of phenomena that have conventionally been studied in the realm of quantum optics. These studies have not only deepened our understanding of light-matter interactions but also introduced aspects of many-body correlations inherent in optical processes in condensed matter systems. This article is concerned with superrad… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1602.04374v2-abstract-full').style.display = 'inline'; document.getElementById('1602.04374v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1602.04374v2-abstract-full" style="display: none;"> Recent advances in optical studies of condensed matter have led to the emergence of phenomena that have conventionally been studied in the realm of quantum optics. These studies have not only deepened our understanding of light-matter interactions but also introduced aspects of many-body correlations inherent in optical processes in condensed matter systems. This article is concerned with superradiance (SR), a profound quantum optical process predicted by Dicke in 1954. The basic concept of SR applies to a general $N$-body system where constituent oscillating dipoles couple together through interaction with a common light field and accelerate the radiative decay of the system. In the most fascinating manifestation of SR, known as superfluorescence (SF), an incoherently prepared system of $N$ inverted atoms spontaneously develops macroscopic coherence from vacuum fluctuations and produces a delayed pulse of coherent light whose peak intensity $\propto N^2$. Such SF pulses have been observed in atomic and molecular gases, and their intriguing quantum nature has been unambiguously demonstrated. Here, we focus on the rapidly developing field of research on SR in solids, where not only photon-mediated coupling but also strong Coulomb interactions and ultrafast scattering exist. We describe SR and SF in molecular centers in solids, molecular aggregates and crystals, quantum dots, and quantum wells. In particular, we will summarize a series of studies we have recently performed on quantum wells in strong magnetic fields. These studies show that cooperative effects in solid-state systems are not merely small corrections that require exotic conditions to be observed; rather, they can dominate the nonequilibrium dynamics and light emission processes of the entire system of interacting electrons. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1602.04374v2-abstract-full').style.display = 'none'; document.getElementById('1602.04374v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 29 May, 2016; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 13 February, 2016; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2016. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">23 pages, 26 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Journal of the Optical Society of America B 33, C80 (2016) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1510.07022">arXiv:1510.07022</a> <span> [<a href="https://arxiv.org/pdf/1510.07022">pdf</a>, <a href="https://arxiv.org/ps/1510.07022">ps</a>, <a href="https://arxiv.org/format/1510.07022">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1038/ncomms10643">10.1038/ncomms10643 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Exciton Diamagnetic Shifts and Valley Zeeman Effects in Monolayer WS$_2$ and MoS$_2$ to 65 Tesla </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Stier%2C+A+V">Andreas V. Stier</a>, <a href="/search/cond-mat?searchtype=author&query=McCreary%2C+K+M">Kathleen M. McCreary</a>, <a href="/search/cond-mat?searchtype=author&query=Jonker%2C+B+T">Berend T. Jonker</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a>, <a href="/search/cond-mat?searchtype=author&query=Crooker%2C+S+A">Scott A. Crooker</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1510.07022v1-abstract-short" style="display: inline;"> We report circularly-polarized optical reflection spectroscopy of monolayer WS$_2$ and MoS$_2$ at low temperatures (4~K) and in high magnetic fields to 65~T. Both the A and the B exciton transitions exhibit a clear and very similar Zeeman splitting of approximately $-$230~$渭$eV/T ($g\simeq -4$), providing the first measurements of the valley Zeeman effect and associated $g$-factors in monolayer tr… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1510.07022v1-abstract-full').style.display = 'inline'; document.getElementById('1510.07022v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1510.07022v1-abstract-full" style="display: none;"> We report circularly-polarized optical reflection spectroscopy of monolayer WS$_2$ and MoS$_2$ at low temperatures (4~K) and in high magnetic fields to 65~T. Both the A and the B exciton transitions exhibit a clear and very similar Zeeman splitting of approximately $-$230~$渭$eV/T ($g\simeq -4$), providing the first measurements of the valley Zeeman effect and associated $g$-factors in monolayer transition-metal disulphides. These results complement and are compared with recent low-field photoluminescence measurements of valley degeneracy breaking in the monolayer diselenides MoSe$_2$ and WSe$_2$. Further, the very large magnetic fields used in our studies allows us to observe the small quadratic diamagnetic shifts of the A and B excitons in monolayer WS$_2$ (0.32 and 0.11~$渭$eV/T$^2$, respectively), from which we calculate exciton radii of 1.53~nm and 1.16~nm. When analyzed within a model of non-local dielectric screening in monolayer semiconductors, these diamagnetic shifts also constrain and provide estimates of the exciton binding energies (410~meV and 470~meV for the A and B excitons, respectively), further highlighting the utility of high magnetic fields for understanding new 2D materials. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1510.07022v1-abstract-full').style.display = 'none'; document.getElementById('1510.07022v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 23 October, 2015; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2015. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">9 pages, 5 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Nature Communications 7: 10643 (2016) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1505.02702">arXiv:1505.02702</a> <span> [<a href="https://arxiv.org/pdf/1505.02702">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1002/adom.201500237">10.1002/adom.201500237 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Uncooled Carbon Nanotube Photodetectors </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=He%2C+X">Xiaowei He</a>, <a href="/search/cond-mat?searchtype=author&query=Leonard%2C+F">Francois Leonard</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1505.02702v1-abstract-short" style="display: inline;"> Photodetectors play key roles in many applications such as remote sensing, night vision, reconnaissance, medical imaging, thermal imaging, and chemical detection. Several properties such as performance, reliability, ease of integration, cost, weight, and form factor are all important in determining the attributes of photodetectors for particular applications. While a number of materials have been… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1505.02702v1-abstract-full').style.display = 'inline'; document.getElementById('1505.02702v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1505.02702v1-abstract-full" style="display: none;"> Photodetectors play key roles in many applications such as remote sensing, night vision, reconnaissance, medical imaging, thermal imaging, and chemical detection. Several properties such as performance, reliability, ease of integration, cost, weight, and form factor are all important in determining the attributes of photodetectors for particular applications. While a number of materials have been used over the past several decades to address photodetection needs across the electromagnetic spectrum, the advent of nanomaterials opens new possibilities for photodetectors. In particular, carbon-based nanomaterials such as carbon nanotubes (CNTs) and graphene possess unique properties that have recently been explored for photodetectors. Here, we review the status of the field, presenting a broad coverage of the different types of photodetectors that have been realized with CNTs, placing particular emphasis on the types of mechanisms that govern their operation. We present a comparative summary of the main performance metrics for such detectors, and an outlook for performance improvements. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1505.02702v1-abstract-full').style.display = 'none'; document.getElementById('1505.02702v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 11 May, 2015; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2015. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">73 pages, 21 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Advanced Optical Materials 3, 989 (2015) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1405.1132">arXiv:1405.1132</a> <span> [<a href="https://arxiv.org/pdf/1405.1132">pdf</a>, <a href="https://arxiv.org/format/1405.1132">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevLett.113.047601">10.1103/PhysRevLett.113.047601 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Superradiant Decay of Cyclotron Resonance of Two-Dimensional Electron Gases </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+Q">Qi Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Arikawa%2C+T">Takashi Arikawa</a>, <a href="/search/cond-mat?searchtype=author&query=Kato%2C+E">Eiji Kato</a>, <a href="/search/cond-mat?searchtype=author&query=Reno%2C+J+L">John L. Reno</a>, <a href="/search/cond-mat?searchtype=author&query=Pan%2C+W">Wei Pan</a>, <a href="/search/cond-mat?searchtype=author&query=Watson%2C+J+D">John D. Watson</a>, <a href="/search/cond-mat?searchtype=author&query=Manfra%2C+M+J">Michael J. Manfra</a>, <a href="/search/cond-mat?searchtype=author&query=Zudov%2C+M+A">Michael A. Zudov</a>, <a href="/search/cond-mat?searchtype=author&query=Tokman%2C+M">Michail Tokman</a>, <a href="/search/cond-mat?searchtype=author&query=Erukhimova%2C+M">Maria Erukhimova</a>, <a href="/search/cond-mat?searchtype=author&query=Belyanin%2C+A">Alexey Belyanin</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">Junichiro Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1405.1132v1-abstract-short" style="display: inline;"> We report on the observation of collective radiative decay, or superradiance, of cyclotron resonance (CR) in high-mobility two-dimensional electron gases in GaAs quantum wells using time-domain terahertz magnetospectroscopy. The decay rate of coherent CR oscillations increases linearly with the electron density in a wide range, which is a hallmark of superradiant damping. Our fully quantum mechani… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1405.1132v1-abstract-full').style.display = 'inline'; document.getElementById('1405.1132v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1405.1132v1-abstract-full" style="display: none;"> We report on the observation of collective radiative decay, or superradiance, of cyclotron resonance (CR) in high-mobility two-dimensional electron gases in GaAs quantum wells using time-domain terahertz magnetospectroscopy. The decay rate of coherent CR oscillations increases linearly with the electron density in a wide range, which is a hallmark of superradiant damping. Our fully quantum mechanical theory provides a universal formula for the decay rate, which reproduces our experimental data without any adjustable parameter. These results firmly establish the many-body nature of CR decoherence in this system, despite the fact that the CR frequency is immune to electron-electron interactions due to Kohn's theorem. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1405.1132v1-abstract-full').style.display = 'none'; document.getElementById('1405.1132v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 5 May, 2014; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2014. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">5 pages, 4 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Physical Review Letters 113, 047601 (2014) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1404.5592">arXiv:1404.5592</a> <span> [<a href="https://arxiv.org/pdf/1404.5592">pdf</a>, <a href="https://arxiv.org/ps/1404.5592">ps</a>, <a href="https://arxiv.org/format/1404.5592">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1364/AO.53.005850">10.1364/AO.53.005850 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Rapid Scanning Terahertz Time-Domain Magnetospectroscopy with a Table-Top Repetitive Pulsed Magnet </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Noe%2C+G+T">G. T. Noe</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+Q">Q. Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Lee%2C+J">J. Lee</a>, <a href="/search/cond-mat?searchtype=author&query=Kato%2C+E">E. Kato</a>, <a href="/search/cond-mat?searchtype=author&query=Woods%2C+G+L">G. L. Woods</a>, <a href="/search/cond-mat?searchtype=author&query=Nojiri%2C+H">H. Nojiri</a>, <a href="/search/cond-mat?searchtype=author&query=Kono%2C+J">J. Kono</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1404.5592v1-abstract-short" style="display: inline;"> We have performed terahertz time-domain magnetospectroscopy by combining a rapid scanning terahertz time-domain spectrometer based on the electronically coupled optical sampling method with a table-top mini-coil pulsed magnet capable of producing magnetic fields up to 30 T. We demonstrate the capability of this system by measuring coherent cyclotron resonance oscillations in a high-mobility two-di… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1404.5592v1-abstract-full').style.display = 'inline'; document.getElementById('1404.5592v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1404.5592v1-abstract-full" style="display: none;"> We have performed terahertz time-domain magnetospectroscopy by combining a rapid scanning terahertz time-domain spectrometer based on the electronically coupled optical sampling method with a table-top mini-coil pulsed magnet capable of producing magnetic fields up to 30 T. We demonstrate the capability of this system by measuring coherent cyclotron resonance oscillations in a high-mobility two-dimensional electron gas in GaAs and interference-induced terahertz transmittance modifications in a magnetoplasma in lightly doped n-InSb. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1404.5592v1-abstract-full').style.display = 'none'; document.getElementById('1404.5592v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 22 April, 2014; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2014. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">6 pages, 4 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Applied Optics 53, 5850 (2014) </p> </li> </ol> <nav class="pagination is-small is-centered breathe-horizontal" role="navigation" aria-label="pagination"> <a href="" class="pagination-previous is-invisible">Previous </a> <a href="/search/?searchtype=author&query=Kono%2C+J&start=50" class="pagination-next" >Next </a> <ul class="pagination-list"> <li> <a href="/search/?searchtype=author&query=Kono%2C+J&start=0" class="pagination-link is-current" aria-label="Goto page 1">1 </a> </li> <li> <a href="/search/?searchtype=author&query=Kono%2C+J&start=50" class="pagination-link " aria-label="Page 2" aria-current="page">2 </a> </li> <li> <a href="/search/?searchtype=author&query=Kono%2C+J&start=100" class="pagination-link " aria-label="Page 3" aria-current="page">3 </a> </li> </ul> </nav> <div class="is-hidden-tablet"> <!-- feedback for mobile only --> <span class="help" style="display: inline-block;"><a href="https://github.com/arXiv/arxiv-search/releases">Search v0.5.6 released 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