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<button class="button is-small is-link">Go</button> </div> </div> </form> </div> </div> <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=Birol%2C+T&start=50" class="pagination-next" >Next </a> <ul class="pagination-list"> <li> <a href="/search/?searchtype=author&query=Birol%2C+T&start=0" class="pagination-link is-current" aria-label="Goto page 1">1 </a> </li> <li> <a href="/search/?searchtype=author&query=Birol%2C+T&start=50" class="pagination-link " aria-label="Page 2" aria-current="page">2 </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/2502.19826">arXiv:2502.19826</a> <span> [<a href="https://arxiv.org/pdf/2502.19826">pdf</a>, <a href="https://arxiv.org/format/2502.19826">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Superconductivity">cond-mat.supr-con</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"> Phonon anomalies within the polar charge density wave phase of superconductor Mo$_3$Al$_2$C with structural chirality </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Wu%2C+S">Shangfei Wu</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+X">Xianghan Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Huang%2C+F">Fei-Ting Huang</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Cheong%2C+S">Sang-Wook Cheong</a>, <a href="/search/cond-mat?searchtype=author&query=Blumberg%2C+G">Girsh Blumberg</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="2502.19826v1-abstract-short" style="display: inline;"> We employ polarization-resolved Raman spectroscopy to study the lattice dynamics of the polar charge density wave phase of the superconductor Mo$_3$Al$_2$C with structural chirality. We show the phononic signatures of the charge density wave transition at $T^*$=155K in Mo$_3$Al$_2$C. The detailed temperature dependence of these phonon modes' frequency, half-width-at-half-maximum, and the integrate… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2502.19826v1-abstract-full').style.display = 'inline'; document.getElementById('2502.19826v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2502.19826v1-abstract-full" style="display: none;"> We employ polarization-resolved Raman spectroscopy to study the lattice dynamics of the polar charge density wave phase of the superconductor Mo$_3$Al$_2$C with structural chirality. We show the phononic signatures of the charge density wave transition at $T^*$=155K in Mo$_3$Al$_2$C. The detailed temperature dependence of these phonon modes' frequency, half-width-at-half-maximum, and the integrated area below $T^*$ reveal anomalies at an intermediate temperature $T'\sim$100K, especially for the low-energy modes at 130cm$^{-1}$ and 180cm$^{-1}$. Since these low-energy modes are dominated by Mo-related lattice vibration, we propose that lattice anomalies at $T'$ within the charge density wave phase are related to a modification of the Mo displacements while preserving the crystal symmetry. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2502.19826v1-abstract-full').style.display = 'none'; document.getElementById('2502.19826v1-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 February, 2025; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2025. </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, 6 figures. The supplemental materials are available upon request</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2502.16657">arXiv:2502.16657</a> <span> [<a href="https://arxiv.org/pdf/2502.16657">pdf</a>, <a href="https://arxiv.org/format/2502.16657">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="Superconductivity">cond-mat.supr-con</span> </div> </div> <p class="title is-5 mathjax"> Loop-current order through the kagome looking glass </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Ye%2C+M">Mengxing Ye</a>, <a href="/search/cond-mat?searchtype=author&query=Vanderbilt%2C+D">David Vanderbilt</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="2502.16657v1-abstract-short" style="display: inline;"> In loop-current states, interacting electronic degrees of freedom collectively establish interatomic currents, in a rare example of magnetism in which spin degrees of freedom do not play the primary role. The main impact of such states on the electronic spectrum is not via the standard Zeeman term, but via the kinetic energy, in which hopping parameters develop non-trivial phases that break time-r… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2502.16657v1-abstract-full').style.display = 'inline'; document.getElementById('2502.16657v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2502.16657v1-abstract-full" style="display: none;"> In loop-current states, interacting electronic degrees of freedom collectively establish interatomic currents, in a rare example of magnetism in which spin degrees of freedom do not play the primary role. The main impact of such states on the electronic spectrum is not via the standard Zeeman term, but via the kinetic energy, in which hopping parameters develop non-trivial phases that break time-reversal symmetry. The recent proposal of loop-current states in kagome superconductors has stimulated renewed interest in this exotic type of magnetism. In this perspective, we use kagome materials as a scaffolding to frame the basic phenomenology of loop-current states. We provide an overview of the group-theoretical properties of loop currents, as well as of relevant microscopic models and ab initio methods. Particular emphasis is given to the comparison with spin-density waves in the presence of spin-orbit coupling, as well as to the anharmonic coupling with charge-density waves, which is present in systems with threefold rotational symmetry. We also provide a brief overview of the current status of loop-current order in kagome metals and discuss open challenges including their experimental detection and interplay with other orders. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2502.16657v1-abstract-full').style.display = 'none'; document.getElementById('2502.16657v1-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, 2025; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2025. </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 paper</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2502.08633">arXiv:2502.08633</a> <span> [<a href="https://arxiv.org/pdf/2502.08633">pdf</a>, <a href="https://arxiv.org/ps/2502.08633">ps</a>, <a href="https://arxiv.org/format/2502.08633">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> <p class="title is-5 mathjax"> Triggered ferroelectricity in HfO$_2$ from hybrid phonons </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Jung%2C+S">Seongjoo Jung</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</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="2502.08633v2-abstract-short" style="display: inline;"> Ferroelectric HfO$_2$ has garnered significant attention for its promising application in high density nonvolatile data storage and nanoscale transistors. However, the uncertain origin of polarization in HfO$_2$ limits our ability to fully understand and control its ferroelectricity. The ongoing debate centers on whether HfO$_2$ is a proper or improper ferroelectric, as it exhibits characteristics… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2502.08633v2-abstract-full').style.display = 'inline'; document.getElementById('2502.08633v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2502.08633v2-abstract-full" style="display: none;"> Ferroelectric HfO$_2$ has garnered significant attention for its promising application in high density nonvolatile data storage and nanoscale transistors. However, the uncertain origin of polarization in HfO$_2$ limits our ability to fully understand and control its ferroelectricity. The ongoing debate centers on whether HfO$_2$ is a proper or improper ferroelectric, as it exhibits characteristics of both types. In this study, we utilize symmetry-guided first-principles quantum mechanical (DFT) calculations to accurately map the energy landscape and identify the coherent switching pathway of HfO$_2$ by voltage. Our findings reveal two key insights. First, ferroelectricity in HfO$_2$ is driven by a triggered mechanism through coupling between the stable polar mode and hybrid non-polar modes. Second, unusually high polarization arises from the hybrid modes, which consists solely of non-polar modes. The results fundamentally transforms the perspective on polarization in HfO$_2$ and resolve conflicting characteristics observed, offering valuable guidance for superior technological applications. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2502.08633v2-abstract-full').style.display = 'none'; document.getElementById('2502.08633v2-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 February, 2025; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 12 February, 2025; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2025. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2411.16065">arXiv:2411.16065</a> <span> [<a href="https://arxiv.org/pdf/2411.16065">pdf</a>, <a href="https://arxiv.org/format/2411.16065">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.4c05972">10.1021/acs.nanolett.4c05972 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Octahedral Rotation Induced, Antiferroelectric-like Double Hysteresis in Strained Perovskites </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Jung%2C+S">Seongjoo Jung</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</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="2411.16065v1-abstract-short" style="display: inline;"> Antiferroelectrics, which host both polar and antipolar order parameters, are characterized by the double hysteresis loops which are advantageous for various applications such as high-density energy storage. In this study, we investigate the coupling between oxygen octahedral rotations and polarization in well-known perovskites, with a focus on SrTiO$_3$. Using first-principles calculations and sy… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2411.16065v1-abstract-full').style.display = 'inline'; document.getElementById('2411.16065v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2411.16065v1-abstract-full" style="display: none;"> Antiferroelectrics, which host both polar and antipolar order parameters, are characterized by the double hysteresis loops which are advantageous for various applications such as high-density energy storage. In this study, we investigate the coupling between oxygen octahedral rotations and polarization in well-known perovskites, with a focus on SrTiO$_3$. Using first-principles calculations and symmetry-adapted Landau-Ginzburg-Devonshire theory, we construct an energy landscape to analyze how this coupling shapes polarization-voltage hysteresis behavior. We show that tuning the relative strength of polar and rotational instabilities by exploiting epitaxial strain and layering leads to nontrivial hysteresis behavior. Consequently, the rotation coupling with polarization leads to an expanded search space of materials exhibiting antiferroelectric-like double hysteresis. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2411.16065v1-abstract-full').style.display = 'none'; document.getElementById('2411.16065v1-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 November, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 2024. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2411.04117">arXiv:2411.04117</a> <span> [<a href="https://arxiv.org/pdf/2411.04117">pdf</a>, <a href="https://arxiv.org/format/2411.04117">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> <p class="title is-5 mathjax"> Octupolar vortex crystal and toroidal moment in twisted bilayer MnPSe$_3$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Akram%2C+M">Muhammad Akram</a>, <a href="/search/cond-mat?searchtype=author&query=Yang%2C+F">Fan Yang</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Erten%2C+O">Onur Erten</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="2411.04117v1-abstract-short" style="display: inline;"> Experimental detection of antiferromagnetic order in two-dimensional materials is a challenging task due to the absence of net dipole moments. Identifying multi-domain antiferromagnetic textures via the current techniques is even more difficult. In order to address this challenge, we investigate the higher order multipole moments in twisted bilayer MnPSe$_3$. While the monolayers of MnPSe$_3$ exhi… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2411.04117v1-abstract-full').style.display = 'inline'; document.getElementById('2411.04117v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2411.04117v1-abstract-full" style="display: none;"> Experimental detection of antiferromagnetic order in two-dimensional materials is a challenging task due to the absence of net dipole moments. Identifying multi-domain antiferromagnetic textures via the current techniques is even more difficult. In order to address this challenge, we investigate the higher order multipole moments in twisted bilayer MnPSe$_3$. While the monolayers of MnPSe$_3$ exhibit in-plane N茅el antiferromagnetic order, our atomistic simulations indicate that the moir茅 superlattices display a two-domain phase on each layer. We show that the octupolar moments $M_{33}^+$ and $M_{33}^-$ are significant in this multi-domain phase at the domain walls. In addition, when $[M_{33}^+,M_{33}^-]$ are represented by the $x$ and $y$ components of a vector, the resultant pattern of these octupole moments winds around the antiferromagnetic domains and forms to vortex crystals which leads to octupolar toroidal moments, $T_{xyz}$ and $T_{z}^尾$. $T_{xyz}$ and $T_{z}^尾$ can give rise to a magnetoelectric effect and gyrotropic birefringence that may provide indirect ways of detecting multi-domain antiferromagnetic order. Our results highlight the importance of higher-order multipole moments for identification of complex spin textures in moir茅 magnets. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2411.04117v1-abstract-full').style.display = 'none'; document.getElementById('2411.04117v1-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 November, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 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">22 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/2410.20921">arXiv:2410.20921</a> <span> [<a href="https://arxiv.org/pdf/2410.20921">pdf</a>, <a href="https://arxiv.org/format/2410.20921">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Superconductivity">cond-mat.supr-con</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/s41467-024-53627-1">10.1038/s41467-024-53627-1 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Polar charge density wave in a superconductor with crystallographic chirality </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Wu%2C+S">Shangfei Wu</a>, <a href="/search/cond-mat?searchtype=author&query=Huang%2C+F">Fei-Ting Huang</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+X">Xianghan Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Ritz%2C+E+T">Ethan T. Ritz</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Cheong%2C+S">Sang-Wook Cheong</a>, <a href="/search/cond-mat?searchtype=author&query=Blumberg%2C+G">Girsh Blumberg</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="2410.20921v1-abstract-short" style="display: inline;"> Symmetry plays an important role in determining the physical properties in condensed matter physics, as the symmetry operations of any physical property must include the symmetry operations of the point group of the crystal. As a consequence, crystallographic polarity and chirality are expected to have an impact on the Cooper pairing in a superconductor. While superconductivity with crystallograph… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2410.20921v1-abstract-full').style.display = 'inline'; document.getElementById('2410.20921v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2410.20921v1-abstract-full" style="display: none;"> Symmetry plays an important role in determining the physical properties in condensed matter physics, as the symmetry operations of any physical property must include the symmetry operations of the point group of the crystal. As a consequence, crystallographic polarity and chirality are expected to have an impact on the Cooper pairing in a superconductor. While superconductivity with crystallographic polarity and chirality have both been found in a few crystalline phases separately; however, their coexistence and material realizations have not been studied. Here, by utilizing transport, Raman scattering, and transmission electron microscopy, we unveil a unique realization of superconductivity in single-crystalline Mo3Al2C (superconducting Tc=8K) with a polar charge-density-wave phase and well-defined crystallographic chirality. We show that the intriguing charge density wave order leads to a noncentrosymmetric-nonpolar to polar transition below T*=155K via breaking both the translational and rotational symmetries. Superconductivity emerges in this polar and chiral crystal structure below Tc=8K. Our results establish that Mo3Al2C is a superconductor with crystallographic polarity and chirality simultaneously, and motivate future studies of unconventional superconductivity in this category. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2410.20921v1-abstract-full').style.display = 'none'; document.getElementById('2410.20921v1-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">20 pages, 3 figures, journal version</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Nature Communications 15, 9276 (2024) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2406.11212">arXiv:2406.11212</a> <span> [<a href="https://arxiv.org/pdf/2406.11212">pdf</a>, <a href="https://arxiv.org/format/2406.11212">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/10.1038/s41467-024-48883-0">10.1038/s41467-024-48883-0 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Low-Energy Electronic Structure in the Unconventional Charge-Ordered State of ScV$_6$Sn$_6$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Kundu%2C+A+K">Asish K. Kundu</a>, <a href="/search/cond-mat?searchtype=author&query=Huang%2C+X">Xiong Huang</a>, <a href="/search/cond-mat?searchtype=author&query=Seewald%2C+E">Eric Seewald</a>, <a href="/search/cond-mat?searchtype=author&query=Ritz%2C+E">Ethan Ritz</a>, <a href="/search/cond-mat?searchtype=author&query=Pakhira%2C+S">Santanu Pakhira</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+S">Shuai Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Sun%2C+D">Dihao Sun</a>, <a href="/search/cond-mat?searchtype=author&query=Turkel%2C+S">Simon Turkel</a>, <a href="/search/cond-mat?searchtype=author&query=Shabani%2C+S">Sara Shabani</a>, <a href="/search/cond-mat?searchtype=author&query=Yilmaz%2C+T">Turgut Yilmaz</a>, <a href="/search/cond-mat?searchtype=author&query=Vescovo%2C+E">Elio Vescovo</a>, <a href="/search/cond-mat?searchtype=author&query=Dean%2C+C+R">Cory R. Dean</a>, <a href="/search/cond-mat?searchtype=author&query=Johnston%2C+D+C">David C. Johnston</a>, <a href="/search/cond-mat?searchtype=author&query=Valla%2C+T">Tonica Valla</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Basov%2C+D+N">Dmitri N. Basov</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</a>, <a href="/search/cond-mat?searchtype=author&query=Pasupathy%2C+A+N">Abhay N. Pasupathy</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="2406.11212v1-abstract-short" style="display: inline;"> Kagome vanadates {\it A}V$_3$Sb$_5$ display unusual low-temperature electronic properties including charge density waves (CDW), whose microscopic origin remains unsettled. Recently, CDW order has been discovered in a new material ScV$_6$Sn$_6$, providing an opportunity to explore whether the onset of CDW leads to unusual electronic properties. Here, we study this question using angle-resolved phot… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2406.11212v1-abstract-full').style.display = 'inline'; document.getElementById('2406.11212v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2406.11212v1-abstract-full" style="display: none;"> Kagome vanadates {\it A}V$_3$Sb$_5$ display unusual low-temperature electronic properties including charge density waves (CDW), whose microscopic origin remains unsettled. Recently, CDW order has been discovered in a new material ScV$_6$Sn$_6$, providing an opportunity to explore whether the onset of CDW leads to unusual electronic properties. Here, we study this question using angle-resolved photoemission spectroscopy (ARPES) and scanning tunneling microscopy (STM). The ARPES measurements show minimal changes to the electronic structure after the onset of CDW. However, STM quasiparticle interference (QPI) measurements show strong dispersing features related to the CDW ordering vectors. A plausible explanation is the presence of a strong momentum-dependent scattering potential peaked at the CDW wavevector, associated with the existence of competing CDW instabilities. Our STM results further indicate that the bands most affected by the CDW are near vHS, analogous to the case of {\it A}V$_3$Sb$_5$ despite very different CDW wavevectors. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2406.11212v1-abstract-full').style.display = 'none'; document.getElementById('2406.11212v1-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 June, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 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">33 pages, 4 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Nat. Commun. 15, 5008 (2024) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2405.05838">arXiv:2405.05838</a> <span> [<a href="https://arxiv.org/pdf/2405.05838">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="Other Condensed Matter">cond-mat.other</span> </div> </div> <p class="title is-5 mathjax"> Altermagnetic Polar Metallic phase in Ultra-Thin Epitaxially-Strained RuO2 Films </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Jeong%2C+S+G">Seung Gyo Jeong</a>, <a href="/search/cond-mat?searchtype=author&query=Choi%2C+I+H">In Hyeok Choi</a>, <a href="/search/cond-mat?searchtype=author&query=Nair%2C+S">Sreejith Nair</a>, <a href="/search/cond-mat?searchtype=author&query=Buiarelli%2C+L">Luca Buiarelli</a>, <a href="/search/cond-mat?searchtype=author&query=Pourbahari%2C+B">Bita Pourbahari</a>, <a href="/search/cond-mat?searchtype=author&query=Oh%2C+J+Y">Jin Young Oh</a>, <a href="/search/cond-mat?searchtype=author&query=Bassim%2C+N">Nabil Bassim</a>, <a href="/search/cond-mat?searchtype=author&query=Hirai%2C+D">Daigorou Hirai</a>, <a href="/search/cond-mat?searchtype=author&query=Seo%2C+A">Ambrose Seo</a>, <a href="/search/cond-mat?searchtype=author&query=Choi%2C+W+S">Woo Seok Choi</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Zhao%2C+L">Liuyan Zhao</a>, <a href="/search/cond-mat?searchtype=author&query=Lee%2C+J+S">Jong Seok Lee</a>, <a href="/search/cond-mat?searchtype=author&query=Jalan%2C+B">Bharat Jalan</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="2405.05838v2-abstract-short" style="display: inline;"> Altermagnetism refers to a wide class of magnetic orders featuring magnetic sublattices with opposite spins related by rotational symmetries, resulting in non-trivial spin splitting and magnetic multipoles. However, the direct observation of the altermagnetic order parameter remains elusive. Here, by combining theoretical analysis, electrical transport, X-ray and optical spectroscopies, we establi… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2405.05838v2-abstract-full').style.display = 'inline'; document.getElementById('2405.05838v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2405.05838v2-abstract-full" style="display: none;"> Altermagnetism refers to a wide class of magnetic orders featuring magnetic sublattices with opposite spins related by rotational symmetries, resulting in non-trivial spin splitting and magnetic multipoles. However, the direct observation of the altermagnetic order parameter remains elusive. Here, by combining theoretical analysis, electrical transport, X-ray and optical spectroscopies, we establish a phase diagram in hybrid molecular beam epitaxy-grown RuO2/TiO2 (110) films, mapping symmetries along with altermagnetic/electronic/structural phase transitions as functions of film thickness and temperature. This features a novel altermagnetic metallic polar phase in epitaxially-strained 2 nm films, extending the concept of multiferroicity to altermagnets. Such a clear signature of a magnetic phase transition at ~500 K is observed exclusively in ultrathin strained films, unlike in bulk RuO2 single crystals. These results demonstrate the potential of epitaxial heterostructure design to induce altermagnetism, paving the way for emergent novel phases with multifunctional properties. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2405.05838v2-abstract-full').style.display = 'none'; document.getElementById('2405.05838v2-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> 13 February, 2025; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 9 May, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 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">23 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/2405.02149">arXiv:2405.02149</a> <span> [<a href="https://arxiv.org/pdf/2405.02149">pdf</a>, <a href="https://arxiv.org/format/2405.02149">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="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/PhysRevLett.134.016401">10.1103/PhysRevLett.134.016401 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Piezoresistivity as a Fingerprint of Ferroaxial Transitions </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Day-Roberts%2C+E">Ezra Day-Roberts</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</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="2405.02149v2-abstract-short" style="display: inline;"> Recent progress in the understanding of the collective behavior of electrons and ions have revealed new types of ferroic orders beyond ferroelectricity and ferromagnetism, such as the ferroaxial state. The latter retains only rotational symmetry around a single axis and reflection symmetry with respect to a single mirror plane, both of which are set by an emergent electric toroidal dipole moment.… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2405.02149v2-abstract-full').style.display = 'inline'; document.getElementById('2405.02149v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2405.02149v2-abstract-full" style="display: none;"> Recent progress in the understanding of the collective behavior of electrons and ions have revealed new types of ferroic orders beyond ferroelectricity and ferromagnetism, such as the ferroaxial state. The latter retains only rotational symmetry around a single axis and reflection symmetry with respect to a single mirror plane, both of which are set by an emergent electric toroidal dipole moment. Due to this unusual symmetry-breaking pattern, it has been challenging to directly measure the ferroaxial order parameter, despite the increasing attention this state has drawn. Here, we show that off-diagonal components of the piezoresistivity tensor (i.e., the linear change in resistivity under strain) transform the same way as the ferroaxial moments, providing a direct probe of such order parameters. We identify two new proper ferroaxial materials through a materials database search, and use first-principles calculations to evaluate the piezoconductivity of the double-perovskite CaSnF$_6$, revealing its connection to ferroaxial order and to octahedral rotation modes. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2405.02149v2-abstract-full').style.display = 'none'; document.getElementById('2405.02149v2-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 March, 2025; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 3 May, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2024. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Lett. 134, 016401 (2025) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2311.12969">arXiv:2311.12969</a> <span> [<a href="https://arxiv.org/pdf/2311.12969">pdf</a>, <a href="https://arxiv.org/format/2311.12969">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> <p class="title is-5 mathjax"> Effect of (001) and (111) Epitaxial Strain on \emph{Pnma} Perovskite Oxides </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Saha%2C+A">Amartyajyoti Saha</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</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="2311.12969v1-abstract-short" style="display: inline;"> With recent advances in strain engineering and its widespread applications, it is becoming increasingly important to understand the effect of biaxial strain on the most common structural phase of perovskites -- the orthorhombic $Pnma$ structure. In this work, by using a combination of group theory and first principles density functional theory, we study the effect of biaxial strain on (001) and (1… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2311.12969v1-abstract-full').style.display = 'inline'; document.getElementById('2311.12969v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2311.12969v1-abstract-full" style="display: none;"> With recent advances in strain engineering and its widespread applications, it is becoming increasingly important to understand the effect of biaxial strain on the most common structural phase of perovskites -- the orthorhombic $Pnma$ structure. In this work, by using a combination of group theory and first principles density functional theory, we study the effect of biaxial strain on (001) and (111)-oriented CaTiO$_3$, SrSnO$_3$ and SrZrO$_3$ films. We observe manifestly different behaviors depending on the strain orientation, with common trends emerging between different materials. In addition to many different structural phases observed in individual compounds before, we identify a transition between two different phases with the same space group name ($P2_1/c$) but different symmetries in (111)-strained materials. We also find that allowing the relaxation of the out-of-plane monoclinic angles, often ignored in first principles studies, lead to significant stabilization of certain phases and is essential to correctly determine the structural ground state. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2311.12969v1-abstract-full').style.display = 'none'; document.getElementById('2311.12969v1-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 November, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 2023. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2311.06127">arXiv:2311.06127</a> <span> [<a href="https://arxiv.org/pdf/2311.06127">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="Materials Science">cond-mat.mtrl-sci</span> </div> </div> <p class="title is-5 mathjax"> First-order phase transition vs. spin-state quantum-critical scenarios in strain-tuned epitaxial cobaltite thin films </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Dewey%2C+J+E">J. E. Dewey</a>, <a href="/search/cond-mat?searchtype=author&query=Chaturvedi%2C+V">V. Chaturvedi</a>, <a href="/search/cond-mat?searchtype=author&query=Webb%2C+T+A">T. A. Webb</a>, <a href="/search/cond-mat?searchtype=author&query=Sharma%2C+P">P. Sharma</a>, <a href="/search/cond-mat?searchtype=author&query=Postiglione%2C+W+M">W. M. Postiglione</a>, <a href="/search/cond-mat?searchtype=author&query=Quarterman%2C+P">P. Quarterman</a>, <a href="/search/cond-mat?searchtype=author&query=Balakrishnan%2C+P+P">P. P. Balakrishnan</a>, <a href="/search/cond-mat?searchtype=author&query=Kirby%2C+B+J">B. J. Kirby</a>, <a href="/search/cond-mat?searchtype=author&query=Figari%2C+L">L. Figari</a>, <a href="/search/cond-mat?searchtype=author&query=Korostynski%2C+C">C. Korostynski</a>, <a href="/search/cond-mat?searchtype=author&query=Jacobson%2C+A">A. Jacobson</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">T. Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">R. M. Fernandes</a>, <a href="/search/cond-mat?searchtype=author&query=Pasupathy%2C+A+N">A. N. Pasupathy</a>, <a href="/search/cond-mat?searchtype=author&query=Leighton%2C+C">C. Leighton</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="2311.06127v1-abstract-short" style="display: inline;"> Pr-containing perovskite cobaltites exhibit unusual valence transitions, coupled to coincident structural, spin-state, and metal-insulator transitions. Heteroepitaxial strain was recently used to control these phenomena in the model (Pr$_{1-y}$Y$_y$)$_{1-x}$Ca$_x$CoO$_{3-未}$ system, stabilizing a nonmagnetic insulating phase under compression (with a room-temperature valence/spin-state/metal-insul… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2311.06127v1-abstract-full').style.display = 'inline'; document.getElementById('2311.06127v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2311.06127v1-abstract-full" style="display: none;"> Pr-containing perovskite cobaltites exhibit unusual valence transitions, coupled to coincident structural, spin-state, and metal-insulator transitions. Heteroepitaxial strain was recently used to control these phenomena in the model (Pr$_{1-y}$Y$_y$)$_{1-x}$Ca$_x$CoO$_{3-未}$ system, stabilizing a nonmagnetic insulating phase under compression (with a room-temperature valence/spin-state/metal-insulator transition) and a ferromagnetic metallic phase under tension, thus exposing a potential spin-state quantum critical point. The latter has been proposed in cobaltites and can be probed in this system as a function of a disorder-free variable (strain). We study this here via thickness-dependent strain relaxation in compressive SrLaAlO$_4$(001)/(Pr$_{0.85}$Y$_{0.15}$)$_{0.70}$Ca$_{0.30}$CoO$_{3-未}$ epitaxial thin films to quasi-continuously probe structural, electronic, and magnetic behaviors across the nonmagnetic-insulator/ferromagnetic-metal boundary. High-resolution X-ray diffraction, electronic transport, magnetometry, polarized neutron reflectometry, and temperature-dependent magnetic force microscopy provide a detailed picture, including abundant evidence of temperature- and strain-dependent phase coexistence. This indicates a first-order phase transition as opposed to spin-state quantum-critical behavior, which we discuss theoretically via a phenomenological Landau model for coupled spin-state and magnetic phase transitions. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2311.06127v1-abstract-full').style.display = 'none'; document.getElementById('2311.06127v1-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> 10 November, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 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 + supplementary material</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2309.14314">arXiv:2309.14314</a> <span> [<a href="https://arxiv.org/pdf/2309.14314">pdf</a>, <a href="https://arxiv.org/format/2309.14314">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/PhysRevX.14.011043">10.1103/PhysRevX.14.011043 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Symmetry breaking and ascending in the magnetic kagome metal FeGe </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Wu%2C+S">Shangfei Wu</a>, <a href="/search/cond-mat?searchtype=author&query=Klemm%2C+M">Mason Klemm</a>, <a href="/search/cond-mat?searchtype=author&query=Shah%2C+J">Jay Shah</a>, <a href="/search/cond-mat?searchtype=author&query=Ritz%2C+E+T">Ethan T. Ritz</a>, <a href="/search/cond-mat?searchtype=author&query=Duan%2C+C">Chunruo Duan</a>, <a href="/search/cond-mat?searchtype=author&query=Teng%2C+X">Xiaokun Teng</a>, <a href="/search/cond-mat?searchtype=author&query=Gao%2C+B">Bin Gao</a>, <a href="/search/cond-mat?searchtype=author&query=Ye%2C+F">Feng Ye</a>, <a href="/search/cond-mat?searchtype=author&query=Matsuda%2C+M">Masaaki Matsuda</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+F">Fankang Li</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+X">Xianghan Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Yi%2C+M">Ming Yi</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Dai%2C+P">Pengcheng Dai</a>, <a href="/search/cond-mat?searchtype=author&query=Blumberg%2C+G">Girsh Blumberg</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="2309.14314v2-abstract-short" style="display: inline;"> Spontaneous symmetry breaking-the phenomenon where an infinitesimal perturbation can cause the system to break the underlying symmetry-is a cornerstone concept in the understanding of interacting solid-state systems. In a typical series of temperature-driven phase transitions, higher temperature phases are more symmetric due to the stabilizing effect of entropy that becomes dominant as the tempera… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2309.14314v2-abstract-full').style.display = 'inline'; document.getElementById('2309.14314v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2309.14314v2-abstract-full" style="display: none;"> Spontaneous symmetry breaking-the phenomenon where an infinitesimal perturbation can cause the system to break the underlying symmetry-is a cornerstone concept in the understanding of interacting solid-state systems. In a typical series of temperature-driven phase transitions, higher temperature phases are more symmetric due to the stabilizing effect of entropy that becomes dominant as the temperature is increased. However, the opposite is rare but possible when there are multiple degrees of freedom in the system. Here, we present such an example of a symmetry-ascending phenomenon in a magnetic kagome metal FeGe by utilizing neutron Larmor diffraction and Raman spectroscopy. In the paramagnetic state at 460K, we confirm that the crystal structure is indeed hexagonal kagome lattice. On cooling to TN, the crystal structure changes from hexagonal to monoclinic with in-plane lattice distortions on the order of 10^(-4) and the associated splitting of the double degenerate phonon mode of the pristine kagome lattice. Upon further cooling to TCDW, the kagome lattice shows a small negative thermal expansion, and the crystal structure becomes more symmetric gradually upon further cooling. Increasing the crystalline symmetry upon cooling is unusual, it originates from an extremely weak structural instability that coexists and competes with the CDW and magnetic orders. These observations are against the expectations for a simple model with a single order parameter, hence can only be explained by a Landau free energy expansion that takes into account multiple lattice, charge, and spin degrees of freedom. Thus, the determination of the crystalline lattice symmetry as well as the unusual spin-lattice coupling is a first step towards understanding the rich electronic and magnetic properties of the system and sheds new light on intertwined orders where the lattice degree of freedom is no longer dominant. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2309.14314v2-abstract-full').style.display = 'none'; document.getElementById('2309.14314v2-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 March, 2024; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 25 September, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 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">20 pages with 10 figures, replaced with journal version</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. X 14, 011043 (2024) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2308.14257">arXiv:2308.14257</a> <span> [<a href="https://arxiv.org/pdf/2308.14257">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> <p class="title is-5 mathjax"> Crystal-Chemical Origins of the Ultrahigh Conductivity of Metallic Delafossites </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+Y">Yi Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Tutt%2C+F">Fred Tutt</a>, <a href="/search/cond-mat?searchtype=author&query=Evans%2C+G+N">Guy N. Evans</a>, <a href="/search/cond-mat?searchtype=author&query=Sharma%2C+P">Prachi Sharma</a>, <a href="/search/cond-mat?searchtype=author&query=Haugstad%2C+G">Greg Haugstad</a>, <a href="/search/cond-mat?searchtype=author&query=Kaiser%2C+B">Ben Kaiser</a>, <a href="/search/cond-mat?searchtype=author&query=Ramberger%2C+J">Justin Ramberger</a>, <a href="/search/cond-mat?searchtype=author&query=Bayliff%2C+S">Samuel Bayliff</a>, <a href="/search/cond-mat?searchtype=author&query=Tao%2C+Y">Yu Tao</a>, <a href="/search/cond-mat?searchtype=author&query=Manno%2C+M">Mike Manno</a>, <a href="/search/cond-mat?searchtype=author&query=Garcia-Barriocanal%2C+J">Javier Garcia-Barriocanal</a>, <a href="/search/cond-mat?searchtype=author&query=Chaturvedi%2C+V">Vipul Chaturvedi</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Seyfried%2C+W+E">William E. Seyfried Jr.</a>, <a href="/search/cond-mat?searchtype=author&query=Leighton%2C+C">Chris Leighton</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="2308.14257v2-abstract-short" style="display: inline;"> Despite their highly anisotropic complex-oxidic nature, certain delafossite compounds (e.g., PdCoO2, PtCoO2) are the most conductive oxides known, for reasons that remain poorly understood. Their room-temperature conductivity can exceed that of Au, while their low-temperature electronic mean-free-paths reach an astonishing 20 microns. It is widely accepted that these materials must be ultrapure to… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2308.14257v2-abstract-full').style.display = 'inline'; document.getElementById('2308.14257v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2308.14257v2-abstract-full" style="display: none;"> Despite their highly anisotropic complex-oxidic nature, certain delafossite compounds (e.g., PdCoO2, PtCoO2) are the most conductive oxides known, for reasons that remain poorly understood. Their room-temperature conductivity can exceed that of Au, while their low-temperature electronic mean-free-paths reach an astonishing 20 microns. It is widely accepted that these materials must be ultrapure to achieve this, although the methods for their growth (which produce only small crystals) are not typically capable of such. Here, we first report a new approach to PdCoO2 crystal growth, using chemical vapor transport methods to achieve order-of-magnitude gains in size, the highest structural qualities yet reported, and record residual resistivity ratios (>440). Nevertheless, the first detailed mass spectrometry measurements on these materials reveal that they are not ultrapure, typically harboring 100s-of-parts-per-million impurity levels. Through quantitative crystal-chemical analyses, we resolve this apparent dichotomy, showing that the vast majority of impurities are forced to reside in the Co-O octahedral layers, leaving the conductive Pd sheets highly pure (~1 ppm impurity concentrations). These purities are shown to be in quantitative agreement with measured residual resistivities. We thus conclude that a previously unconsidered "sublattice purification" mechanism is essential to the ultrahigh low-temperature conductivity and mean-free-path of metallic delafossites. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2308.14257v2-abstract-full').style.display = 'none'; document.getElementById('2308.14257v2-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 September, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 27 August, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2023. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2308.10342">arXiv:2308.10342</a> <span> [<a href="https://arxiv.org/pdf/2308.10342">pdf</a>, <a href="https://arxiv.org/format/2308.10342">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/10.1103/PhysRevMaterials.7.094407">10.1103/PhysRevMaterials.7.094407 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Tetrahedral rotations in alkaline-earth metal orthovanadates </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Saha%2C+A">Amartyajyoti Saha</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</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="2308.10342v2-abstract-short" style="display: inline;"> The alkaline-earth orthovanadate Sr$_3$V$_2$O$_8$ with the palmierite structure is reported to host a dielectric anomaly as well as a structural phase transition above the room temperature. With V$^{5+}$ ions and tetrahedral oxygen coordination, the crystal structure of this compound is not studied in detail from first principles yet. In this work, we perform a detailed analysis of the crystal str… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2308.10342v2-abstract-full').style.display = 'inline'; document.getElementById('2308.10342v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2308.10342v2-abstract-full" style="display: none;"> The alkaline-earth orthovanadate Sr$_3$V$_2$O$_8$ with the palmierite structure is reported to host a dielectric anomaly as well as a structural phase transition above the room temperature. With V$^{5+}$ ions and tetrahedral oxygen coordination, the crystal structure of this compound is not studied in detail from first principles yet. In this work, we perform a detailed analysis of the crystal structure and instabilities of M$_3$V$_2$O$_8$ ($\text{M} = \text{Ca, Sr, Ba}$) orthovanadates with the palmierite structure using first principles density functional theory. We find that as the M$^{2+}$ cation size decreases, a significant structural distortion that changes the symmetry from $R\bar{3}m$ to $C2/c$ emerges. This change is accompanied with a rotation of the oxygen tetrahedra. Our calculations also indicate that the polar instability in these compounds are suppressed by these tetrahedral rotations. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2308.10342v2-abstract-full').style.display = 'none'; document.getElementById('2308.10342v2-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 September, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 20 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">Journal ref:</span> Phys. Rev. Materials 7, 094407 (2023) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2308.04128">arXiv:2308.04128</a> <span> [<a href="https://arxiv.org/pdf/2308.04128">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> </div> </div> <p class="title is-5 mathjax"> Optical Manipulation of the Charge Density Wave state in RbV3Sb5 </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Xing%2C+Y">Yuqing Xing</a>, <a href="/search/cond-mat?searchtype=author&query=Bae%2C+S">Seokjin Bae</a>, <a href="/search/cond-mat?searchtype=author&query=Ritz%2C+E">Ethan Ritz</a>, <a href="/search/cond-mat?searchtype=author&query=Yang%2C+F">Fan Yang</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Salinas%2C+A+N+C">Andrea N. Capa Salinas</a>, <a href="/search/cond-mat?searchtype=author&query=Ortiz%2C+B+R">Brenden R. Ortiz</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=Fernandes%2C+R+M">Rafael M. Fernandes</a>, <a href="/search/cond-mat?searchtype=author&query=Madhavan%2C+V">Vidya Madhavan</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="2308.04128v2-abstract-short" style="display: inline;"> Broken time-reversal symmetry in the absence of spin order indicates the presence of unusual phases such as orbital magnetism and loop currents. The recently discovered family of kagome superconductors AV$_3$Sb$_5$ (A = K, Rb, or Cs), hosting an exotic charge-density wave (CDW) state, has emerged as a strong candidate for this phase. While initial experiments suggested that the CDW phase breaks ti… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2308.04128v2-abstract-full').style.display = 'inline'; document.getElementById('2308.04128v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2308.04128v2-abstract-full" style="display: none;"> Broken time-reversal symmetry in the absence of spin order indicates the presence of unusual phases such as orbital magnetism and loop currents. The recently discovered family of kagome superconductors AV$_3$Sb$_5$ (A = K, Rb, or Cs), hosting an exotic charge-density wave (CDW) state, has emerged as a strong candidate for this phase. While initial experiments suggested that the CDW phase breaks time-reversal symmetry, this idea is being intensely debated due to conflicting experimental data. In this work we use laser-coupled scanning tunneling microscopy (STM) to study RbV$_3$Sb$_5$. STM data shows that the Fourier intensities of all three CDW peaks are different, implying that the CDW breaks rotational and mirror symmetries. By applying linearly polarized light along high-symmetry directions, we show that the relative intensities of the CDW peaks can be reversibly switched, implying a substantial electro-striction response, indicative of strong non-linear electron-phonon coupling. A similar CDW intensity switching is observed with perpendicular magnetic fields, which implies an unusual piezo-magnetic response that, in turn, requires time-reversal symmetry-breaking. We show that the simplest CDW that satisfies these constraints and reconciles previous seemingly contradictory experimental data is an out-of-phase combination of bond charge order and loop currents that we dub congruent CDW flux phase. Our laser-STM data opens the door to the possibility of dynamic optical control of complex quantum phenomenon in correlated materials. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2308.04128v2-abstract-full').style.display = 'none'; document.getElementById('2308.04128v2-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 March, 2024; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 8 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">main text: 21 pages, 5 figures // Methods and Extended Data: 25 pages, 14 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/2307.12380">arXiv:2307.12380</a> <span> [<a href="https://arxiv.org/pdf/2307.12380">pdf</a>, <a href="https://arxiv.org/format/2307.12380">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="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.109.024404">10.1103/PhysRevB.109.024404 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Topological transition from nodal to nodeless Zeeman splitting in altermagnets </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</a>, <a href="/search/cond-mat?searchtype=author&query=de+Carvalho%2C+V+S">Vanuildo S. de Carvalho</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Pereira%2C+R+G">Rodrigo G. Pereira</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="2307.12380v4-abstract-short" style="display: inline;"> In an altermagnet, the symmetry that relates configurations with flipped magnetic moments is a rotation. This makes it qualitatively different from a ferromagnet, where no such symmetry exists, or a collinear antiferromagnet, where this symmetry is a lattice translation. In this paper, we investigate the impact of the crystalline environment, enabled by the spin-orbit coupling, on the magnetic and… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2307.12380v4-abstract-full').style.display = 'inline'; document.getElementById('2307.12380v4-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2307.12380v4-abstract-full" style="display: none;"> In an altermagnet, the symmetry that relates configurations with flipped magnetic moments is a rotation. This makes it qualitatively different from a ferromagnet, where no such symmetry exists, or a collinear antiferromagnet, where this symmetry is a lattice translation. In this paper, we investigate the impact of the crystalline environment, enabled by the spin-orbit coupling, on the magnetic and electronic properties of an altermagnet. We find that, because each component of the magnetization acquires its own angular dependence, the Zeeman splitting of the bands has symmetry-protected nodal lines residing on mirror planes of the crystal. Upon crossing the Fermi surface, these nodal lines give rise to pinch points that behave as single or double type-II Weyl nodes. We show that an external magnetic field perpendicular to these mirror planes can only move the nodal lines, such that a critical field value is necessary to collapse the nodes and make the Weyl pinch points annihilate. This unveils the topological nature of the transition from a nodal to a nodeless Zeeman splitting of the bands. We also classify the altermagnetic states of common crystallographic point groups in the presence of spin-orbit coupling, revealing that a broad family of magnetic orthorhombic perovskites can realize altermagnetism. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2307.12380v4-abstract-full').style.display = 'none'; document.getElementById('2307.12380v4-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">v1</span> submitted 23 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">Comments:</span> <span class="has-text-grey-dark mathjax">revised manuscript accepted for publication as an Editors' Suggestion in PRB</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 109, 024404 (2024) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2305.04280">arXiv:2305.04280</a> <span> [<a href="https://arxiv.org/pdf/2305.04280">pdf</a>, <a href="https://arxiv.org/format/2305.04280">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.108.134406">10.1103/PhysRevB.108.134406 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Effect of random antiferromagnetic exchange on the spin waves in a three-dimensional Heisenberg ferromagnet </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Hameed%2C+S">S. Hameed</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%2C+Z">Z. Wang</a>, <a href="/search/cond-mat?searchtype=author&query=Gautreau%2C+D+M">D. M. Gautreau</a>, <a href="/search/cond-mat?searchtype=author&query=Joe%2C+J">J. Joe</a>, <a href="/search/cond-mat?searchtype=author&query=Olson%2C+K+P">K. P. Olson</a>, <a href="/search/cond-mat?searchtype=author&query=Chi%2C+S">S. Chi</a>, <a href="/search/cond-mat?searchtype=author&query=Gehring%2C+P+M">P. M. Gehring</a>, <a href="/search/cond-mat?searchtype=author&query=Hong%2C+T">T. Hong</a>, <a href="/search/cond-mat?searchtype=author&query=Pajerowski%2C+D+M">D. M. Pajerowski</a>, <a href="/search/cond-mat?searchtype=author&query=Williams%2C+T+J">T. J. Williams</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+Z">Z. Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Matsuda%2C+M">M. Matsuda</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">T. Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">R. M. Fernandes</a>, <a href="/search/cond-mat?searchtype=author&query=Greven%2C+M">M. Greven</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="2305.04280v1-abstract-short" style="display: inline;"> Neutron scattering is used to study spin waves in the three-dimensional Heisenberg ferromagnet YTiO$_3$, with spin-spin exchange disorder introduced $via$ La-substitution at the Y site. No significant changes are observed in the spin-wave dispersion up to a La concentration of 20%. However, a strong broadening of the spectrum is found, indicative of shortened spin-wave lifetimes. Density-functiona… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2305.04280v1-abstract-full').style.display = 'inline'; document.getElementById('2305.04280v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2305.04280v1-abstract-full" style="display: none;"> Neutron scattering is used to study spin waves in the three-dimensional Heisenberg ferromagnet YTiO$_3$, with spin-spin exchange disorder introduced $via$ La-substitution at the Y site. No significant changes are observed in the spin-wave dispersion up to a La concentration of 20%. However, a strong broadening of the spectrum is found, indicative of shortened spin-wave lifetimes. Density-functional theory calculations predict minimal changes in exchange constants as a result of average structural changes due to La substitution, in agreement with the data. The absence of significant changes in the spin-wave dispersion, the considerable lifetime effect, and the reduced ordered magnetic moment previously observed in the La-substituted system are qualitatively captured by an isotropic, nearest-neighbor, three-dimensional Heisenberg ferromagnet model with random antiferromagnetic exchange. We therefore establish Y$_{1-x}$La$_x$TiO$_3$ as a model system to study the effect of antiferromagnetic spin-exchange disorder in a three-dimensional Heisenberg ferromagnet. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2305.04280v1-abstract-full').style.display = 'none'; document.getElementById('2305.04280v1-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 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">6 pages and 5 figures in main text. Supplementary material included</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 108, 134406 (2023) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2305.01086">arXiv:2305.01086</a> <span> [<a href="https://arxiv.org/pdf/2305.01086">pdf</a>, <a href="https://arxiv.org/format/2305.01086">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/s41535-023-00590-7">10.1038/s41535-023-00590-7 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Origin and stability of the charge density wave in ScV$_6$Sn$_6$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Gu%2C+Y">Yanhong Gu</a>, <a href="/search/cond-mat?searchtype=author&query=Ritz%2C+E">Ethan Ritz</a>, <a href="/search/cond-mat?searchtype=author&query=Meier%2C+W+R">William R. Meier</a>, <a href="/search/cond-mat?searchtype=author&query=Blockmon%2C+A">Avery Blockmon</a>, <a href="/search/cond-mat?searchtype=author&query=Smith%2C+K">Kevin Smith</a>, <a href="/search/cond-mat?searchtype=author&query=Madhogaria%2C+R+P">Richa Pokharel Madhogaria</a>, <a href="/search/cond-mat?searchtype=author&query=Mozaffari%2C+S">Shirin Mozaffari</a>, <a href="/search/cond-mat?searchtype=author&query=Mandrus%2C+D">David Mandrus</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Musfeldt%2C+J+L">Janice L. Musfeldt</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="2305.01086v1-abstract-short" style="display: inline;"> Kagome metals are widely recognized as versatile platforms for exploring novel topological properties, unconventional electronic correlations, magnetic frustration, and superconductivity. In the $R$V$_6$Sn$_6$ family of materials ($R$ = Sc, Y, Lu), ScV$_6$Sn$_6$ hosts an unusual charge density wave ground state as well as structural similarities with the $A$V$_3$Sb$_5$ system ($A$ = K, Cs, Rb). In… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2305.01086v1-abstract-full').style.display = 'inline'; document.getElementById('2305.01086v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2305.01086v1-abstract-full" style="display: none;"> Kagome metals are widely recognized as versatile platforms for exploring novel topological properties, unconventional electronic correlations, magnetic frustration, and superconductivity. In the $R$V$_6$Sn$_6$ family of materials ($R$ = Sc, Y, Lu), ScV$_6$Sn$_6$ hosts an unusual charge density wave ground state as well as structural similarities with the $A$V$_3$Sb$_5$ system ($A$ = K, Cs, Rb). In this work, we combine Raman scattering spectroscopy with first-principles lattice dynamics calculations to reveal the charge density wave state in ScV$_6$Sn$_6$. In the low temperature phase, we find a five-fold splitting of the V-containing totally symmetric mode near 240 cm$^{-1}$ suggesting that the density wave acts to mix modes of $P$6/$mmm$ and $R$$\bar{3}$$m$ symmetry - an effect that we quantify by projecting phonons of the high symmetry state onto those of the lower symmetry structure. We also test the stability of the density wave state under compression and find that both physical and chemical pressure act to quench the effect. We discuss these findings in terms of symmetry and the structure-property trends that can be unraveled in this system. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2305.01086v1-abstract-full').style.display = 'none'; document.getElementById('2305.01086v1-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 May, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2023. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2304.14822">arXiv:2304.14822</a> <span> [<a href="https://arxiv.org/pdf/2304.14822">pdf</a>, <a href="https://arxiv.org/format/2304.14822">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Superconductivity">cond-mat.supr-con</span> <span class="tag is-small is-grey 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.108.L100510">10.1103/PhysRevB.108.L100510 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Superconductivity from Orbital-Selective Electron-Phonon Coupling in $A\mathrm{V}_3\mathrm{Sb}_5$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Ritz%2C+E+T">Ethan T. Ritz</a>, <a href="/search/cond-mat?searchtype=author&query=R%C3%B8ising%2C+H+S">Henrik S. R酶ising</a>, <a href="/search/cond-mat?searchtype=author&query=Christensen%2C+M+H">Morten H. Christensen</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Andersen%2C+B+M">Brian M. Andersen</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</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="2304.14822v2-abstract-short" style="display: inline;"> Recent experiments have shown that the phase diagrams of the kagome superconductors $A\mathrm{V}_3\mathrm{Sb}_5$ are strongly impacted by changes in the $c$-axis lattice parameter. Here, we show that $c$-axis deformations impact primarily the Sb apical bonds and thus the overlap between their $p_z$ orbitals. Changes in the latter, in turn, substantially affect low-energy electronic states with sig… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2304.14822v2-abstract-full').style.display = 'inline'; document.getElementById('2304.14822v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2304.14822v2-abstract-full" style="display: none;"> Recent experiments have shown that the phase diagrams of the kagome superconductors $A\mathrm{V}_3\mathrm{Sb}_5$ are strongly impacted by changes in the $c$-axis lattice parameter. Here, we show that $c$-axis deformations impact primarily the Sb apical bonds and thus the overlap between their $p_z$ orbitals. Changes in the latter, in turn, substantially affect low-energy electronic states with significant Sb character, most notably the central electron pocket and the van Hove singularities located above the Fermi level. Based on the orbital-selective character of $c$-axis strain, we argue that these electronic states experience a non-negligible attractive electron-phonon pairing interaction mediated by fluctuations in the apical Sb bonds. We thus propose a multi-band model for superconductivity in $A\mathrm{V}_3\mathrm{Sb}_5$ that includes both the Sb pocket and the V-derived van Hove singularities. Upon comparing the theoretical phase diagram with the experimentally observed vanishing of the $T_c$ dome across a Lifshitz transition of the Sb pocket, we propose that either an $s^{+-}$ or an $s^{++}$ state is realized in $A\mathrm{V}_3\mathrm{Sb}_5$. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2304.14822v2-abstract-full').style.display = 'none'; document.getElementById('2304.14822v2-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 September, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 28 April, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 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+5 pages, 2+4 figures. Accepted in Phys. Rev. B</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Report number:</span> NBI CMT 2023 </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 108, L100510 (2023) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2304.05443">arXiv:2304.05443</a> <span> [<a href="https://arxiv.org/pdf/2304.05443">pdf</a>, <a href="https://arxiv.org/format/2304.05443">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Superconductivity">cond-mat.supr-con</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/s41586-022-05521-3">10.1038/s41586-022-05521-3 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Coupled Ferroelectricity and Superconductivity in Bilayer $T_d$-MoTe$_2$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Jindal%2C+A">Apoorv Jindal</a>, <a href="/search/cond-mat?searchtype=author&query=Saha%2C+A">Amartyajyoti Saha</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+Z">Zizhong Li</a>, <a href="/search/cond-mat?searchtype=author&query=Taniguchi%2C+T">Takashi Taniguchi</a>, <a href="/search/cond-mat?searchtype=author&query=Watanabe%2C+K">Kenji Watanabe</a>, <a href="/search/cond-mat?searchtype=author&query=Hone%2C+J+C">James C. Hone</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</a>, <a href="/search/cond-mat?searchtype=author&query=Dean%2C+C+R">Cory R. Dean</a>, <a href="/search/cond-mat?searchtype=author&query=Pasupathy%2C+A+N">Abhay N. Pasupathy</a>, <a href="/search/cond-mat?searchtype=author&query=Rhodes%2C+D+A">Daniel A. Rhodes</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="2304.05443v1-abstract-short" style="display: inline;"> Achieving electrostatic control of quantum phases is at the frontier of condensed matter research. Recent investigations have revealed superconductivity tunable by electrostatic doping in twisted graphene heterostructures and in two-dimensional (2D) semimetals such as WTe$_2$. Some of these systems have a polar crystal structure that gives rise to ferroelectricity, in which the interlayer polariza… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2304.05443v1-abstract-full').style.display = 'inline'; document.getElementById('2304.05443v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2304.05443v1-abstract-full" style="display: none;"> Achieving electrostatic control of quantum phases is at the frontier of condensed matter research. Recent investigations have revealed superconductivity tunable by electrostatic doping in twisted graphene heterostructures and in two-dimensional (2D) semimetals such as WTe$_2$. Some of these systems have a polar crystal structure that gives rise to ferroelectricity, in which the interlayer polarization exhibits bistability driven by external electric fields. Here we show that bilayer $T_d$-MoTe$_2$ simultaneously exhibits ferroelectric switching and superconductivity. Remarkably, a field-driven, first-order superconductor-to-normal transition is observed at its ferroelectric transition. Bilayer $T_d$-MoTe$_2$ also has a maximum in its superconducting transition temperature ($T_\textrm{c}$) as a function of carrier density and temperature, allowing independent control of the superconducting state as a function of both doping and polarization. We find that the maximum $T_\textrm{c}$ is concomitant with compensated electron and hole carrier densities and vanishes when one of the Fermi pockets disappears with doping. We argue that this unusual polarization-sensitive 2D superconductor is driven by an interband pairing interaction associated with nearly nested electron and hole Fermi pockets. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2304.05443v1-abstract-full').style.display = 'none'; document.getElementById('2304.05443v1-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 April, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2023. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Nature 613, 48-52 (2023) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2212.13319">arXiv:2212.13319</a> <span> [<a href="https://arxiv.org/pdf/2212.13319">pdf</a>, <a href="https://arxiv.org/format/2212.13319">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="Strongly Correlated Electrons">cond-mat.str-el</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/PhysRevB.107.205131">10.1103/PhysRevB.107.205131 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Impact of Sb degrees of freedom on the charge density wave phase diagram of the kagome metal CsV$_3$Sb$_5$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Ritz%2C+E+T">Ethan T. Ritz</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</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="2212.13319v1-abstract-short" style="display: inline;"> Elucidating the microscopic mechanisms responsible for the charge density wave (CDW) instability of the AV$_3$Sb$_5$ (A=Cs, K, Rb) family of kagome metals is critical for understanding their unique properties, including superconductivity. In these compounds, distinct CDW phases with wave-vectors at the $M$ and $L$ points are energetically favorable, opening the possibility of tuning the type of CD… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2212.13319v1-abstract-full').style.display = 'inline'; document.getElementById('2212.13319v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2212.13319v1-abstract-full" style="display: none;"> Elucidating the microscopic mechanisms responsible for the charge density wave (CDW) instability of the AV$_3$Sb$_5$ (A=Cs, K, Rb) family of kagome metals is critical for understanding their unique properties, including superconductivity. In these compounds, distinct CDW phases with wave-vectors at the $M$ and $L$ points are energetically favorable, opening the possibility of tuning the type of CDW order by appropriate external parameters. Here, we shed light on the CDW landscape of CsV$_3$Sb$_5$ via a combination of first-principles calculations and phenomenology, which consists of extracting the coefficients of the CDW Landau free-energy expansion from density functional theory. We find that while the main structural distortions of the kagome lattice in the staggered tri-hexagonal CDW phase are along the nearest-neighbor V-V bonds, distortions associated with the Sb ions play a defining role in the energy gain in this and all other CDW states. Moreover, the coupling between ionic displacements from different unit cells is small, thus explaining the existence of multiple CDW instabilities with different modulations along the c-axis. We also investigate how pressure and temperature impact the CDW phase of CsV$_3$Sb$_5$. Increasing pressure does not change the staggered tri-hexagonal CDW ground state, even though the $M$-point CDW instability disappears before the $L$-point one, a behavior that we attribute to the large nonlinear coupling between the order parameters. Upon changing the temperature, we find a narrow regime in which another transition can take place, toward a tri-hexagonal Star-of-David CDW phase. We discuss the implications of our results by comparing them with experiments on this compound. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2212.13319v1-abstract-full').style.display = 'none'; document.getElementById('2212.13319v1-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 December, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2022. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2208.07481">arXiv:2208.07481</a> <span> [<a href="https://arxiv.org/pdf/2208.07481">pdf</a>, <a href="https://arxiv.org/format/2208.07481">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> <p class="title is-5 mathjax"> Strain effect on the ground-state structure of Sr2SnO4 Ruddlesden-Popper oxides </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Yun%2C+H">Hwanhui Yun</a>, <a href="/search/cond-mat?searchtype=author&query=Gautreau%2C+D">Dominique Gautreau</a>, <a href="/search/cond-mat?searchtype=author&query=Mkhoyan%2C+K+A">K. Andre Mkhoyan</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</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="2208.07481v2-abstract-short" style="display: inline;"> Ruddlesden-Popper (RP) oxides (A$_{n+1}$B$_n$O$_{3n+1}$) comprised of perovskite (ABO$_3$)$_n$ slabs can host a wider variety of structural distortions than their perovskite counterparts. This makes accurate structural determination of RP oxides more challenging. In this study, we investigate the structural phase diagram of $n=1$ RP Sr$_2$SnO$_4$, one of alkaline earth stannates that are promising… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2208.07481v2-abstract-full').style.display = 'inline'; document.getElementById('2208.07481v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2208.07481v2-abstract-full" style="display: none;"> Ruddlesden-Popper (RP) oxides (A$_{n+1}$B$_n$O$_{3n+1}$) comprised of perovskite (ABO$_3$)$_n$ slabs can host a wider variety of structural distortions than their perovskite counterparts. This makes accurate structural determination of RP oxides more challenging. In this study, we investigate the structural phase diagram of $n=1$ RP Sr$_2$SnO$_4$, one of alkaline earth stannates that are promising for opto-electronic applications by using group theory-based symmetry analysis and first-principles calculations. We explore the symmetry breaking effects of different dynamical instabilities, predict the energies of phases they lead to, and take into account different (biaxial strain and hydrostatic pressure) boundary conditions. We also address the effect of structural changes on the electronic structure and find that compressive biaxial strain drives Sr$_2$SnO$_4$ into a regime with wider bandgap and lower electron effective mass. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2208.07481v2-abstract-full').style.display = 'none'; document.getElementById('2208.07481v2-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> 4 October, 2022; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 15 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/2207.12820">arXiv:2207.12820</a> <span> [<a href="https://arxiv.org/pdf/2207.12820">pdf</a>, <a href="https://arxiv.org/format/2207.12820">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="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/PhysRevB.106.144504">10.1103/PhysRevB.106.144504 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Loop currents in $A$V$_3$Sb$_5$ kagome metals: multipolar and toroidal magnetic orders </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Christensen%2C+M+H">Morten H. Christensen</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Andersen%2C+B+M">Brian M. Andersen</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</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="2207.12820v2-abstract-short" style="display: inline;"> Experiments in the recently discovered vanadium-based kagome metals have suggested that their charge-ordered state displays not only bond distortions, characteristic of a ``real" charge density-wave (rCDW), but also time-reversal symmetry-breaking, typical of loop currents described by an ``imaginary" charge density-wave (iCDW). Here, we combine density-functional theory, group-theory, and phenome… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2207.12820v2-abstract-full').style.display = 'inline'; document.getElementById('2207.12820v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2207.12820v2-abstract-full" style="display: none;"> Experiments in the recently discovered vanadium-based kagome metals have suggested that their charge-ordered state displays not only bond distortions, characteristic of a ``real" charge density-wave (rCDW), but also time-reversal symmetry-breaking, typical of loop currents described by an ``imaginary" charge density-wave (iCDW). Here, we combine density-functional theory, group-theory, and phenomenological modeling to investigate the complex charge-ordered states that arise from interactions between the low-energy van Hove singularities present in the electronic structure of $A$V$_3$Sb$_5$. We find two broad classes of mixed iCDW-rCDW configurations: triple-$\mathbf{Q}$ iCDW, triple-$\mathbf{Q}$ rCDW order, dubbed $3\mathbf{Q}$-$3\mathbf{Q}$, and double-$\mathbf{Q}$ iCDW, single-$\mathbf{Q}$ rCDW order, dubbed $2\mathbf{Q}$-$1\mathbf{Q}$. Moreover, we identify seven different types of iCDW order, stemming from the different vanadium-orbital and kagome-sublattice structures of the two pairs of van Hove singularities present above and below the Fermi level. While the $2\mathbf{Q}$-$1\mathbf{Q}$ states trigger an orthorhombic distortion that breaks the threefold rotational symmetry of the kagome lattice, the $3\mathbf{Q}$-$3\mathbf{Q}$ states induce various types of subsidiary uniform magnetic orders, from conventional ferromagnetism to magnetic octupolar, magnetic toroidal, and even magnetic monopolar order. We show that these exotic orders display unique magneto-striction, magneto-electric, and magneto-electric-striction properties that can be probed experimentally to identify which iCDW state is realized in these compounds. We briefly discuss the impact of an out-of-plane modulation of the charge order and the interplay between these complex charge-ordered states and superconductivity. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2207.12820v2-abstract-full').style.display = 'none'; document.getElementById('2207.12820v2-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 October, 2022; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 26 July, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 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">20 pages, 8 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Report number:</span> NBI CMT 2022 </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 106, 144504 (2022) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2203.13355">arXiv:2203.13355</a> <span> [<a href="https://arxiv.org/pdf/2203.13355">pdf</a>, <a href="https://arxiv.org/format/2203.13355">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.107.085150">10.1103/PhysRevB.107.085150 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Gating-Induced Mott Transition in NiS$_2$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Day-Roberts%2C+E">Ezra Day-Roberts</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</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="2203.13355v2-abstract-short" style="display: inline;"> NiS$_2$ has been widely regarded as a model system to study the bandwidth-controlled Mott transition, as enabled by isovalent Se chemical substitution on the S sites. Motivated by advances in electrolyte gating, we theoretically investigate the filling-controlled Mott transition induced by gating, which has the advantage of avoiding dopant disorder and stoichiometric changes. We use combined Densi… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2203.13355v2-abstract-full').style.display = 'inline'; document.getElementById('2203.13355v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2203.13355v2-abstract-full" style="display: none;"> NiS$_2$ has been widely regarded as a model system to study the bandwidth-controlled Mott transition, as enabled by isovalent Se chemical substitution on the S sites. Motivated by advances in electrolyte gating, we theoretically investigate the filling-controlled Mott transition induced by gating, which has the advantage of avoiding dopant disorder and stoichiometric changes. We use combined Density Functional Theory (DFT) and Dynamical Mean Field Theory (DMFT) to study such a filling-controlled transition and compare it with the case of bandwidth control. We draw a temperature-filling phase diagram and find that the Mott-insulator to metal transition occurs with modest added electron concentrations, well within the capabilities of existing electrolyte gating experiments. We find that there is significant incoherent weight at the Fermi level in the metallic phase when the transition is induced by gating. In contrast, the spectral weight remains rather coherent in the case of the bandwidth-controlled transition. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2203.13355v2-abstract-full').style.display = 'none'; document.getElementById('2203.13355v2-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 February, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 24 March, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2022. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2203.12317">arXiv:2203.12317</a> <span> [<a href="https://arxiv.org/pdf/2203.12317">pdf</a>, <a href="https://arxiv.org/format/2203.12317">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="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/PhysRevResearch.4.023244">10.1103/PhysRevResearch.4.023244 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Charge order breaks time-reversal symmetry in CsV$_3$Sb$_5$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Khasanov%2C+R">Rustem Khasanov</a>, <a href="/search/cond-mat?searchtype=author&query=Das%2C+D">Debarchan Das</a>, <a href="/search/cond-mat?searchtype=author&query=Gupta%2C+R">Ritu Gupta</a>, <a href="/search/cond-mat?searchtype=author&query=Mielke%2C+C">Charles Mielke III</a>, <a href="/search/cond-mat?searchtype=author&query=Elender%2C+M">Matthias Elender</a>, <a href="/search/cond-mat?searchtype=author&query=Yin%2C+Q">Qiangwei Yin</a>, <a href="/search/cond-mat?searchtype=author&query=Tu%2C+Z">Zhijun Tu</a>, <a href="/search/cond-mat?searchtype=author&query=Gong%2C+C">Chunsheng Gong</a>, <a href="/search/cond-mat?searchtype=author&query=Lei%2C+H">Hechang Lei</a>, <a href="/search/cond-mat?searchtype=author&query=Ritz%2C+E">Ethan Ritz</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Guguchia%2C+Z">Zurab Guguchia</a>, <a href="/search/cond-mat?searchtype=author&query=Luetkens%2C+H">Hubertus Luetkens</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="2203.12317v1-abstract-short" style="display: inline;"> The recently discovered vanadium-based kagome metals $A$V$_{3}$Sb$_{5}$ ($A$~=~K,~Rb,~Cs) exhibit superconductivity at low-temperatures and charge density wave (CDW) order at high-temperatures. A prominent feature of the charge ordered state in this family is that it breaks time-reversal symmetry (TRSB), which is connected to the underlying topological nature of the band structure. In this work, a… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2203.12317v1-abstract-full').style.display = 'inline'; document.getElementById('2203.12317v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2203.12317v1-abstract-full" style="display: none;"> The recently discovered vanadium-based kagome metals $A$V$_{3}$Sb$_{5}$ ($A$~=~K,~Rb,~Cs) exhibit superconductivity at low-temperatures and charge density wave (CDW) order at high-temperatures. A prominent feature of the charge ordered state in this family is that it breaks time-reversal symmetry (TRSB), which is connected to the underlying topological nature of the band structure. In this work, a powerful combination of zero-field and high-field muon-spin rotation/relaxation is used to study the signatures of TRSB of the charge order in CsV$_3$Sb$_5$, as well as its anisotropic character. By tracking the temperature evolution of the in-plane and out-of-plane components of the muon-spin polarization, an enhancement of the internal field width sensed by the muon-spin ensemble was observed below $T_{\rm TRSB}=T_{\rm CDW}\simeq95$~K. Additional increase of the internal field width, accompanied by a change of the local field direction at the muon site from the $ab$-plane to the $c$-axis, was detected below $T^\ast\simeq30$~K. Remarkably, this two-step feature becomes well pronounced when a magnetic field of 8~T is applied along the crystallographic $c-$axis, thus indicating a field-induced enhancement of the electronic response at the CDW transition. These results point to a TRSB in CsV$_3$Sb$_5$ by charge order with an onset of ${\simeq}~95$~K, followed by an enhanced electronic response below ${\simeq}~30$~K. The observed two-step transition is discussed within the framework of different charge-order instabilities, which, in accordance with density functional theory calculations, are nearly degenerate in energy. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2203.12317v1-abstract-full').style.display = 'none'; document.getElementById('2203.12317v1-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 March, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 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">10 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. Research 4, 023244 (2022) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2203.05055">arXiv:2203.05055</a> <span> [<a href="https://arxiv.org/pdf/2203.05055">pdf</a>, <a href="https://arxiv.org/format/2203.05055">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Superconductivity">cond-mat.supr-con</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"> Two types of charge order in the superconducting kagome material CsV$_3$Sb$_5$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Gupta%2C+R">Ritu Gupta</a>, <a href="/search/cond-mat?searchtype=author&query=Das%2C+D">Debarchan Das</a>, <a href="/search/cond-mat?searchtype=author&query=Mielke%2C+C">Charles Mielke III</a>, <a href="/search/cond-mat?searchtype=author&query=Ritz%2C+E">Ethan Ritz</a>, <a href="/search/cond-mat?searchtype=author&query=Hotz%2C+F">Fabian Hotz</a>, <a href="/search/cond-mat?searchtype=author&query=Yin%2C+Q">Qiangwei Yin</a>, <a href="/search/cond-mat?searchtype=author&query=Tu%2C+Z">Zhijun Tu</a>, <a href="/search/cond-mat?searchtype=author&query=Gong%2C+C">Chunsheng Gong</a>, <a href="/search/cond-mat?searchtype=author&query=Lei%2C+H">Hechang Lei</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</a>, <a href="/search/cond-mat?searchtype=author&query=Guguchia%2C+Z">Zurab Guguchia</a>, <a href="/search/cond-mat?searchtype=author&query=Luetkens%2C+H">Hubertus Luetkens</a>, <a href="/search/cond-mat?searchtype=author&query=Khasanov%2C+R">Rustem Khasanov</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="2203.05055v1-abstract-short" style="display: inline;"> The kagome metals of the family $A$V$_3$Sb$_5$, featuring a unique structural motif, harbor an array of intriguing phenomena such as chiral charge order and superconductivity. CsV$_3$Sb$_5$ is of particular interest because it displays a double superconducting dome in the region of the temperature-pressure phase diagram where charge order is still present. However, the microscopic origin of such a… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2203.05055v1-abstract-full').style.display = 'inline'; document.getElementById('2203.05055v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2203.05055v1-abstract-full" style="display: none;"> The kagome metals of the family $A$V$_3$Sb$_5$, featuring a unique structural motif, harbor an array of intriguing phenomena such as chiral charge order and superconductivity. CsV$_3$Sb$_5$ is of particular interest because it displays a double superconducting dome in the region of the temperature-pressure phase diagram where charge order is still present. However, the microscopic origin of such an unusual behavior remains an unsolved issue. Here, to address it, we combine high-pressure, low-temperature muon spin relaxation with first-principles calculations. We observe a pressure-induced threefold enhancement of the superfluid density, which also displays a double peak feature, similar to the superconducting critical temperature. This leads to three distinct regions in the phase diagram, each of which features distinct slopes of the linear relation between superfluid density and the critical temperature. These results are attributed to a possible evolution of the charge order pattern from the superimposed tri-hexagonal Star-of-David phase at low pressures (within the first dome) to the staggered tri-hexagonal phase at intermediate pressures (between the first and second domes). Our findings suggest a change in the nature of the charge ordered state across the phase diagram of CsV$_3$Sb$_5$, with varying degrees of competition with superconductivity. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2203.05055v1-abstract-full').style.display = 'none'; document.getElementById('2203.05055v1-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 March, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 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">9 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/2201.05188">arXiv:2201.05188</a> <span> [<a href="https://arxiv.org/pdf/2201.05188">pdf</a>, <a href="https://arxiv.org/format/2201.05188">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.105.155106">10.1103/PhysRevB.105.155106 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Charge density wave order in kagome metal AV$_3$Sb$_5$ (A= Cs, Rb, K) </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Wu%2C+S">Shangfei Wu</a>, <a href="/search/cond-mat?searchtype=author&query=Ortiz%2C+B+R">Brenden R. Ortiz</a>, <a href="/search/cond-mat?searchtype=author&query=Tan%2C+H">Hengxin Tan</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=Yan%2C+B">Binghai Yan</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Blumberg%2C+G">Girsh Blumberg</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="2201.05188v2-abstract-short" style="display: inline;"> We employ polarization-resolved electronic Raman spectroscopy and density functional theory to study the primary and secondary order parameters, as well as their interplay, in the charge density wave (CDW) state of the kagome metal AV3Sb5. Previous x-ray diffraction data at 15K established that the CDW order in CsV3Sb5 comprises of a 2x2x4 structure: one layer of inverse-star-of-David and three co… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2201.05188v2-abstract-full').style.display = 'inline'; document.getElementById('2201.05188v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2201.05188v2-abstract-full" style="display: none;"> We employ polarization-resolved electronic Raman spectroscopy and density functional theory to study the primary and secondary order parameters, as well as their interplay, in the charge density wave (CDW) state of the kagome metal AV3Sb5. Previous x-ray diffraction data at 15K established that the CDW order in CsV3Sb5 comprises of a 2x2x4 structure: one layer of inverse-star-of-David and three consecutive layers of star-of-David pattern. We analyze the lattice distortions based the 2x2x4 structure at 15K, and find that U lattice distortion is the primary order parameter while M and L distortions are secondary order parameters for Vanadium displacements. This conclusion is confirmed by the calculation of bare susceptibility that shows a broad peak at around qz=0.25 along the hexagonal Brillouin zone face central line (U-line). We also identify several phonon modes emerging in the CDW state, which are lattice vibration modes related to V and Sb atoms as well as alkali atoms. The detailed temperature evolution of these modes' frequencies, HWHM, and integrated intensities support a phase diagram with two successive structural phase transitions in CsV3Sb5: the first one with a primary order parameter appearing at TS=94K and the second isostructural one appearing at around 70K. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2201.05188v2-abstract-full').style.display = 'none'; document.getElementById('2201.05188v2-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 April, 2022; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 13 January, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2022. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2112.10917">arXiv:2112.10917</a> <span> [<a href="https://arxiv.org/pdf/2112.10917">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/10.1038/s41467-022-35024-8">10.1038/s41467-022-35024-8 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Room-Temperature Valence Transition in a Strain-Tuned Perovskite Oxide </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Chaturvedi%2C+V">Vipul Chaturvedi</a>, <a href="/search/cond-mat?searchtype=author&query=Ghosh%2C+S">Supriya Ghosh</a>, <a href="/search/cond-mat?searchtype=author&query=Gautreau%2C+D">Dominique Gautreau</a>, <a href="/search/cond-mat?searchtype=author&query=Postiglione%2C+W+M">William M. Postiglione</a>, <a href="/search/cond-mat?searchtype=author&query=Dewey%2C+J+E">John E. Dewey</a>, <a href="/search/cond-mat?searchtype=author&query=Quarterman%2C+P">Patrick Quarterman</a>, <a href="/search/cond-mat?searchtype=author&query=Balakrishnan%2C+P+P">Purnima P. Balakrishnan</a>, <a href="/search/cond-mat?searchtype=author&query=Kirby%2C+B+J">Brian J. Kirby</a>, <a href="/search/cond-mat?searchtype=author&query=Zhou%2C+H">Hua Zhou</a>, <a href="/search/cond-mat?searchtype=author&query=Cheng%2C+H">Huikai Cheng</a>, <a href="/search/cond-mat?searchtype=author&query=Huon%2C+A">Amanda Huon</a>, <a href="/search/cond-mat?searchtype=author&query=Charlton%2C+T">Timothy Charlton</a>, <a href="/search/cond-mat?searchtype=author&query=Fitzsimmons%2C+M+R">Michael R. Fitzsimmons</a>, <a href="/search/cond-mat?searchtype=author&query=Korostynski%2C+C">Caroline Korostynski</a>, <a href="/search/cond-mat?searchtype=author&query=Jacobson%2C+A">Andrew Jacobson</a>, <a href="/search/cond-mat?searchtype=author&query=Figari%2C+L">Lucca Figari</a>, <a href="/search/cond-mat?searchtype=author&query=Barriocanal%2C+J+G">Javier Garcia Barriocanal</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Mkhoyan%2C+K+A">K. Andre Mkhoyan</a>, <a href="/search/cond-mat?searchtype=author&query=Leighton%2C+C">Chris Leighton</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="2112.10917v2-abstract-short" style="display: inline;"> Cobalt oxides have long been understood to display intriguing phenomena known as spin-state crossovers, where the cobalt ion spin changes vs. temperature, pressure, etc. A very different situation was recently uncovered in praseodymium-containing cobalt oxides, where a first-order coupled spin-state/structural/metal-insulator transition occurs, driven by a remarkable praseodymium valence transitio… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2112.10917v2-abstract-full').style.display = 'inline'; document.getElementById('2112.10917v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2112.10917v2-abstract-full" style="display: none;"> Cobalt oxides have long been understood to display intriguing phenomena known as spin-state crossovers, where the cobalt ion spin changes vs. temperature, pressure, etc. A very different situation was recently uncovered in praseodymium-containing cobalt oxides, where a first-order coupled spin-state/structural/metal-insulator transition occurs, driven by a remarkable praseodymium valence transition. Such valence transitions, particularly when triggering spin-state and metal-insulator transitions, offer highly appealing functionality, but have thus far been confined to cryogenic temperatures in bulk materials (e.g., 90 K in Pr1-xCaxCoO3). Here, we show that in thin films of the complex perovskite (Pr1-yYy)1-xCaxCoO3-未, heteroepitaxial strain tuning enables stabilization of valence-driven spin-state/structural/metal-insulator transitions to at least 291 K, i.e., around room temperature. The technological implications of this result are accompanied by fundamental prospects, as complete strain control of the electronic ground state is demonstrated, from ferromagnetic metal under tension to nonmagnetic insulator under compression, thereby exposing a potential novel quantum critical point. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2112.10917v2-abstract-full').style.display = 'none'; document.getElementById('2112.10917v2-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, 2022; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 20 December, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 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">35 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/2108.02862">arXiv:2108.02862</a> <span> [<a href="https://arxiv.org/pdf/2108.02862">pdf</a>, <a href="https://arxiv.org/ps/2108.02862">ps</a>, <a href="https://arxiv.org/format/2108.02862">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/PhysRevLett.127.049702">10.1103/PhysRevLett.127.049702 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Response to comment on "Spin-lattice coupling and the emergence of the trimerized phase in the $S=1$ kagome antiferromagnet Na$_2$Ti$_3$Cl$_8$", Phys. Rev. Lett. 124, 167203 (2020) </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Paul%2C+A">Arpita Paul</a>, <a href="/search/cond-mat?searchtype=author&query=Chung%2C+C">Chia-Min Chung</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Changlani%2C+H+J">Hitesh J. Changlani</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="2108.02862v1-abstract-short" style="display: inline;"> In the context of the $S=1$ kagome antiferromagnet Na$_2$Ti$_3$Cl$_8$, we respond to the comment by Khomskii et al. [D.I. Khomskii, T. Mizokawa and S.V. Streltsov, Phys. Rev. Lett. 127, 049701 (2021)] on previous work by Paul et al. [A. Paul, C.-M. Chung, T. Birol, and H. J. Changlani, Phys. Rev. Lett. 124, 167203 (2020)]. </span> <span class="abstract-full has-text-grey-dark mathjax" id="2108.02862v1-abstract-full" style="display: none;"> In the context of the $S=1$ kagome antiferromagnet Na$_2$Ti$_3$Cl$_8$, we respond to the comment by Khomskii et al. [D.I. Khomskii, T. Mizokawa and S.V. Streltsov, Phys. Rev. Lett. 127, 049701 (2021)] on previous work by Paul et al. [A. Paul, C.-M. Chung, T. Birol, and H. J. Changlani, Phys. Rev. Lett. 124, 167203 (2020)]. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2108.02862v1-abstract-full').style.display = 'none'; document.getElementById('2108.02862v1-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 August, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 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">PRL title of the response is "Paul et al. Reply"</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Lett. 127, 049702 (2021) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2107.04546">arXiv:2107.04546</a> <span> [<a href="https://arxiv.org/pdf/2107.04546">pdf</a>, <a href="https://arxiv.org/format/2107.04546">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Superconductivity">cond-mat.supr-con</span> <span class="tag is-small is-grey 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.104.214513">10.1103/PhysRevB.104.214513 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Theory of the charge-density wave in $A$V$_3$Sb$_5$ kagome metals </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Christensen%2C+M+H">Morten H. Christensen</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Andersen%2C+B+M">Brian M. Andersen</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</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="2107.04546v2-abstract-short" style="display: inline;"> The family of metallic kagome compounds $A$V$_3$Sb$_5$ ($A$=K, Rb, Cs) was recently discovered to exhibit both superconductivity and charge order. The nature of the charge-density wave (CDW) phase is presently unsettled, which complicates the interpretation of the superconducting ground state. In this paper, we use group-theory and density-functional theory (DFT) to derive and solve a phenomenolog… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2107.04546v2-abstract-full').style.display = 'inline'; document.getElementById('2107.04546v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2107.04546v2-abstract-full" style="display: none;"> The family of metallic kagome compounds $A$V$_3$Sb$_5$ ($A$=K, Rb, Cs) was recently discovered to exhibit both superconductivity and charge order. The nature of the charge-density wave (CDW) phase is presently unsettled, which complicates the interpretation of the superconducting ground state. In this paper, we use group-theory and density-functional theory (DFT) to derive and solve a phenomenological Landau model for this CDW state. The DFT results reveal three unstable phonon modes with the same in-plane momentum but different out-of-plane momenta, whose frequencies depend strongly on the electronic temperature. This is indicative of an electronically-driven CDW, stabilized by features of the in-plane electronic dispersion. Motivated by the DFT analysis, we construct a Landau free-energy expansion for coupled CDW order parameters with wave-vectors at the $M$ and $L$ points of the hexagonal Brillouin zone. We find an unusual trilinear term coupling these different order parameters, which can promote the simultaneous condensation of both CDWs even if the two modes are not nearly-degenerate. We classify the different types of coupled multi-$\bf{Q}$ CDW orders, focusing on those that break the sixfold rotational symmetry and lead to a unit-cell doubling along all three crystallographic directions, as suggested by experiments. We determine a region in parameter space, characterized by large nonlinear Landau coefficients, where these phases - dubbed staggered tri-hexagonal and staggered Star-of-David - are the leading instabilities of the system. Finally, we discuss the implications of our results for the kagome metals. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2107.04546v2-abstract-full').style.display = 'none'; document.getElementById('2107.04546v2-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 July, 2021; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 9 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">Comments:</span> <span class="has-text-grey-dark mathjax">17 pages, 11 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Report number:</span> NBI CMT 2021 </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 104, 214513 (2021) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2107.04545">arXiv:2107.04545</a> <span> [<a href="https://arxiv.org/pdf/2107.04545">pdf</a>, <a href="https://arxiv.org/ps/2107.04545">ps</a>, <a href="https://arxiv.org/format/2107.04545">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Superconductivity">cond-mat.supr-con</span> <span class="tag is-small is-grey 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.104.144506">10.1103/PhysRevB.104.144506 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Revealing the competition between charge-density wave and superconductivity in CsV$_3$Sb$_5$ through uniaxial strain </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Qian%2C+T">Tiema Qian</a>, <a href="/search/cond-mat?searchtype=author&query=Christensen%2C+M+H">Morten H. Christensen</a>, <a href="/search/cond-mat?searchtype=author&query=Hu%2C+C">Chaowei Hu</a>, <a href="/search/cond-mat?searchtype=author&query=Saha%2C+A">Amartyajyoti Saha</a>, <a href="/search/cond-mat?searchtype=author&query=Andersen%2C+B+M">Brian M. Andersen</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Ni%2C+N">Ni Ni</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="2107.04545v2-abstract-short" style="display: inline;"> In this paper we report the impact of uniaxial strain $\varepsilon$ applied along the crystalline $a$ axis on the newly discovered kagome superconductor CsV$_3$Sb$_5$. At ambient conditions, CsV$_3$Sb$_5$ shows a charge-density wave (CDW) transition at $T_{\rm CDW}=94.5$ K and superconducts below $T_C = 3.34$ K. In our study, when the uniaxial strain $\varepsilon$ is varied from $-0.90\%$ to… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2107.04545v2-abstract-full').style.display = 'inline'; document.getElementById('2107.04545v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2107.04545v2-abstract-full" style="display: none;"> In this paper we report the impact of uniaxial strain $\varepsilon$ applied along the crystalline $a$ axis on the newly discovered kagome superconductor CsV$_3$Sb$_5$. At ambient conditions, CsV$_3$Sb$_5$ shows a charge-density wave (CDW) transition at $T_{\rm CDW}=94.5$ K and superconducts below $T_C = 3.34$ K. In our study, when the uniaxial strain $\varepsilon$ is varied from $-0.90\%$ to $0.90\%$, $T_C$ monotonically increases by $\sim 33\%$ from 3.0 K to 4.0 K, giving rise to the empirical relation $T_C (\varepsilon)=3.4+0.56\varepsilon+0.12\varepsilon^2$. On the other hand, for $\varepsilon$ changing from $-0.76\%$ to $1.26\%$, $T_{\rm CDW}$ decreases monotonically by $\sim 10\%$ from 97.5 K to 87.5 K with $T_{\rm CDW}(\varepsilon)=94.5-4.72\varepsilon-0.60\varepsilon^2$. The opposite response of $T_C$ and $T_{\rm CDW}$ to the uniaxial strain suggests strong competition between these two orders. Comparison with hydrostatic pressure measurements indicate that it is the change in the $c$-axis that is responsible for these behaviors of the CDW and superconducting transitions, and that the explicit breaking of the sixfold rotational symmetry by strain has a negligible effect. Combined with our first-principles calculations and phenomenological analysis, we conclude that the enhancement in $T_C$ with decreasing $c$ is caused primarily by the suppression of $T_{\rm CDW}$, rather than strain-induced modifications in the bare superconducting parameters. We propose that the sensitivity of $T_{\rm CDW}$ with respect to the changes in the $c$-axis arises from the impact of the latter on the trilinear coupling between the $M_1^+$ and $L_2^-$ phonon modes associated with the CDW. Overall, our work reveals that the $c$-axis lattice parameter, which can be controlled by both pressure and uniaxial strain, is a powerful tuning knob for the phase diagram of CsV$_3$Sb$_5$. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2107.04545v2-abstract-full').style.display = 'none'; document.getElementById('2107.04545v2-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 July, 2021; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 9 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">Comments:</span> <span class="has-text-grey-dark mathjax">8 pages, 5 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 104 (2021), 144506 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2105.08905">arXiv:2105.08905</a> <span> [<a href="https://arxiv.org/pdf/2105.08905">pdf</a>, <a href="https://arxiv.org/format/2105.08905">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/10.1103/PhysRevLett.127.087601">10.1103/PhysRevLett.127.087601 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Free carrier induced ferroelectricity in layered perovskites </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Li%2C+S">Shutong Li</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</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="2105.08905v1-abstract-short" style="display: inline;"> Doping ferroelectrics with carriers is often detrimental to polarization. This makes the design and discovery of metals that undergo a ferroelectric-like transition challenging. In this letter, we show from first principles that the oxygen octahedral rotations in perovskites are often enhanced by electron doping, and this can be used as a means to strengthen the structural polarization in certain… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2105.08905v1-abstract-full').style.display = 'inline'; document.getElementById('2105.08905v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2105.08905v1-abstract-full" style="display: none;"> Doping ferroelectrics with carriers is often detrimental to polarization. This makes the design and discovery of metals that undergo a ferroelectric-like transition challenging. In this letter, we show from first principles that the oxygen octahedral rotations in perovskites are often enhanced by electron doping, and this can be used as a means to strengthen the structural polarization in certain hybrid-improper ferroelectrics -- compounds in which the polarization is not stabilized by the long range Coulomb interactions but is instead induced by a trilinear coupling to octahedral rotations. We use this design strategy to predict a cation ordered Ruddlesden-Popper compound that can be driven into a metallic ferroelectric-like phase via electrolyte gating. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2105.08905v1-abstract-full').style.display = 'none'; document.getElementById('2105.08905v1-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 May, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2021. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Lett. 127, 087601 (2021) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2105.06695">arXiv:2105.06695</a> <span> [<a href="https://arxiv.org/pdf/2105.06695">pdf</a>, <a href="https://arxiv.org/format/2105.06695">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/PhysRevLett.128.167201">10.1103/PhysRevLett.128.167201 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Uniaxial strain control of bulk ferromagnetism in rare-earth titanates </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Najev%2C+A">Ana Najev</a>, <a href="/search/cond-mat?searchtype=author&query=Hameed%2C+S">Sajna Hameed</a>, <a href="/search/cond-mat?searchtype=author&query=Gautreau%2C+D+M">Dominique M. Gautreau</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%2C+Z">Zhentao Wang</a>, <a href="/search/cond-mat?searchtype=author&query=Joe%2C+J">Joseph Joe</a>, <a href="/search/cond-mat?searchtype=author&query=Po%C5%BEek%2C+M">Miroslav Po啪ek</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</a>, <a href="/search/cond-mat?searchtype=author&query=Greven%2C+M">Martin Greven</a>, <a href="/search/cond-mat?searchtype=author&query=Pelc%2C+D">Damjan Pelc</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="2105.06695v3-abstract-short" style="display: inline;"> The perovskite rare-earth titanates are model Mott insulators with magnetic ground states that are very sensitive to structural distortions. These distortions couple strongly to the orbital degrees of freedom and, in principle, it should be possible to tune the superexchange and the magnetic transition with strain. We investigate the representative system (Y,La,Ca)TiO$_3$, which exhibits low cryst… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2105.06695v3-abstract-full').style.display = 'inline'; document.getElementById('2105.06695v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2105.06695v3-abstract-full" style="display: none;"> The perovskite rare-earth titanates are model Mott insulators with magnetic ground states that are very sensitive to structural distortions. These distortions couple strongly to the orbital degrees of freedom and, in principle, it should be possible to tune the superexchange and the magnetic transition with strain. We investigate the representative system (Y,La,Ca)TiO$_3$, which exhibits low crystallographic symmetry and no structural instabilities. From magnetic susceptibility measurements of the Curie temperature, we demonstrate direct, reversible and continuous control of ferromagnetism by influencing the TiO$_6$ octahedral tilts and rotations with uniaxial strain. The relative change in $T_C$ as a function of strain is well described by ab initio calculations, which provides detailed understanding of the complex interactions among structural, orbital and magnetic properties in rare-earth titanates. The demonstrated manipulation of octahedral distortions opens up far-reaching possibilities for investigations of electron-lattice coupling, competing ground states, and magnetic quantum phase transitions in a wide range of quantum materials. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2105.06695v3-abstract-full').style.display = 'none'; document.getElementById('2105.06695v3-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 April, 2022; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 14 May, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 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">6 pages, 4 figures, nearly published version</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Lett. 128, 167201 (2022) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2105.01559">arXiv:2105.01559</a> <span> [<a href="https://arxiv.org/pdf/2105.01559">pdf</a>, <a href="https://arxiv.org/format/2105.01559">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.105.144404">10.1103/PhysRevB.105.144404 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Strain-tunable metamagnetic critical endpoint in Mott insulating rare-earth titanates </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Wang%2C+Z">Zhentao Wang</a>, <a href="/search/cond-mat?searchtype=author&query=Gautreau%2C+D">Dominique Gautreau</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</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="2105.01559v2-abstract-short" style="display: inline;"> Rare-earth titanates are Mott insulators whose magnetic ground state -- antiferromagnetic (AFM) or ferromagnetic (FM) -- can be tuned by the radius of the rare-earth element. Here, we combine phenomenology and first-principles calculations to shed light on the generic magnetic phase diagram of a chemically substituted titanate on the rare-earth site that interpolates between an AFM and a FM state.… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2105.01559v2-abstract-full').style.display = 'inline'; document.getElementById('2105.01559v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2105.01559v2-abstract-full" style="display: none;"> Rare-earth titanates are Mott insulators whose magnetic ground state -- antiferromagnetic (AFM) or ferromagnetic (FM) -- can be tuned by the radius of the rare-earth element. Here, we combine phenomenology and first-principles calculations to shed light on the generic magnetic phase diagram of a chemically substituted titanate on the rare-earth site that interpolates between an AFM and a FM state. Octahedral rotations present in these perovskites cause the AFM order to acquire a small FM component -- and vice-versa -- removing any multicritical point from the phase diagram. However, for a wide parameter range, a first-order metamagnetic transition line terminating at a critical endpoint survives inside the magnetically ordered phase. Like the liquid-gas transition, a Widom line emerges from the endpoint, characterized by enhanced fluctuations. In contrast to metallic FMs, this metamagnetic transition involves two symmetry-equivalent and insulating canted spin states. Moreover, instead of a magnetic field, we show that uniaxial strain can be used to tune this transition to zero temperature, inducing a quantum critical endpoint. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2105.01559v2-abstract-full').style.display = 'none'; document.getElementById('2105.01559v2-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 April, 2022; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 4 May, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 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">8 pages, 6 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 105, 144404 (2022) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2104.00478">arXiv:2104.00478</a> <span> [<a href="https://arxiv.org/pdf/2104.00478">pdf</a>, <a href="https://arxiv.org/format/2104.00478">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/s41699-021-00226-z">10.1038/s41699-021-00226-z <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Chemical bonding and Born charge in 1T-HfS$_2$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Neal%2C+S+N">Sabine N. Neal</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+S">Shutong Li</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Musfeldt%2C+J+L">Janice L. Musfeldt</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="2104.00478v1-abstract-short" style="display: inline;"> We combine infrared absorption and Raman scattering spectroscopies to explore the properties of the heavy transition metal dichalcogenide 1T-HfS$_2$. We employ the LO-TO splitting of the $E_u$ vibrational mode along with a reevaluation of mode mass, unit cell volume, and dielectric constant to reveal the Born effective charge. We find $Z^*_{\rm{B}}$ = 5.3$e$, in excellent agreement with complement… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2104.00478v1-abstract-full').style.display = 'inline'; document.getElementById('2104.00478v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2104.00478v1-abstract-full" style="display: none;"> We combine infrared absorption and Raman scattering spectroscopies to explore the properties of the heavy transition metal dichalcogenide 1T-HfS$_2$. We employ the LO-TO splitting of the $E_u$ vibrational mode along with a reevaluation of mode mass, unit cell volume, and dielectric constant to reveal the Born effective charge. We find $Z^*_{\rm{B}}$ = 5.3$e$, in excellent agreement with complementary first principles calculations. In addition to resolving controversy over the nature of chemical bonding in this system, we decompose Born charge into polarizability and local charge. We find $伪$ = 5.07 脜$^3$ and $Z^{*}$ = 5.2$e$, respectively. Polar displacement-induced charge transfer from sulfur $p$ to hafnium $d$ is responsible for the enhanced Born charge compared to the nominal 4+ in hafnium. 1T-HfS$_2$ is thus an ionic crystal with strong and dynamic covalent effects. Taken together, our work places the vibrational properties of 1T-HfS$_2$ on a firm foundation and opens the door to understanding the properties of tubes and sheets. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2104.00478v1-abstract-full').style.display = 'none'; document.getElementById('2104.00478v1-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 April, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2021. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> npj 2D Materials and Applications 5, 45 (2021) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2103.08566">arXiv:2103.08566</a> <span> [<a href="https://arxiv.org/pdf/2103.08566">pdf</a>, <a href="https://arxiv.org/format/2103.08566">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.104.045112">10.1103/PhysRevB.104.045112 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Two-component electronic phase separation in the doped Mott insulator Y$_{1-x}$Ca$_{x}$TiO$_{3}$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Hameed%2C+S">S. Hameed</a>, <a href="/search/cond-mat?searchtype=author&query=Joe%2C+J">J. Joe</a>, <a href="/search/cond-mat?searchtype=author&query=Gautreau%2C+D+M">D. M. Gautreau</a>, <a href="/search/cond-mat?searchtype=author&query=Freeland%2C+J+W">J. W. Freeland</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">T. Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Greven%2C+M">M. Greven</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="2103.08566v1-abstract-short" style="display: inline;"> One of the major puzzles in condensed matter physics has been the observation of a Mott-insulating state away from half-filling. The filling-controlled Mott insulator-metal transition, induced via charge-carrier doping, has been extensively researched, but its governing mechanisms have yet to be fully understood. Several theoretical proposals aimed to elucidate the nature of the transition have be… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2103.08566v1-abstract-full').style.display = 'inline'; document.getElementById('2103.08566v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2103.08566v1-abstract-full" style="display: none;"> One of the major puzzles in condensed matter physics has been the observation of a Mott-insulating state away from half-filling. The filling-controlled Mott insulator-metal transition, induced via charge-carrier doping, has been extensively researched, but its governing mechanisms have yet to be fully understood. Several theoretical proposals aimed to elucidate the nature of the transition have been put forth, a notable one being phase separation and an associated percolation-induced transition. In the present work, we study the prototypical doped Mott-insulating rare-earth titanate YTiO$_3$, in which the insulating state survives up to a large hole concentration of 35%. Single crystals of Y$_{1-x}$Ca$_x$TiO$_3$ with $0 \leq x \leq 0.5$, spanning the insulator-metal transition, are grown and investigated. Using x-ray absorption spectroscopy, a powerful technique capable of probing element-specific electronic states, we find that the primary effect of hole doping is to induce electronic phase separation into hole-rich and hole-poor regions. The data reveal the formation of electronic states within the Mott-Hubbard gap, near the Fermi level, which increase in spectral weight with increasing doping. From a comparison with DFT+$U$ calculations, we infer that the hole-poor and hole-rich components have charge densities that correspond to the Mott-insulating $x = 0$ and metallic $x \sim 0.5$ states, respectively, and that the new electronic states arise from the metallic component. Our results indicate that the hole-doping-induced insulator-metal transition in Y$_{1-x}$Ca$_x$TiO$_3$ is indeed percolative in nature, and thus of inherent first-order character. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2103.08566v1-abstract-full').style.display = 'none'; document.getElementById('2103.08566v1-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> 15 March, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 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">15 pages, supplementary material included</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 104, 045112 (2021) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2103.06287">arXiv:2103.06287</a> <span> [<a href="https://arxiv.org/pdf/2103.06287">pdf</a>, <a href="https://arxiv.org/format/2103.06287">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link 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/PhysRevB.103.224522">10.1103/PhysRevB.103.224522 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Robust Gapless Superconductivity in 4Hb-TaS$_2$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Dentelski%2C+D">David Dentelski</a>, <a href="/search/cond-mat?searchtype=author&query=Day-Roberts%2C+E">Ezra Day-Roberts</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</a>, <a href="/search/cond-mat?searchtype=author&query=Ruhman%2C+J">Jonathan Ruhman</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="2103.06287v2-abstract-short" style="display: inline;"> The superconducting TMD 4Hb-TaS$_2$ consists of alternating layers of H and T structures, which in their bulk form are metallic and Mott-insulating, respectively. Recently, this compound has been proposed as a candidate chiral superconductor, due to an observed enhancement of the muon spin relaxation at $T_c$. 4Hb-TaS$_2$ also exhibits a puzzling $T$-linear specific heat at low temperatures, which… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2103.06287v2-abstract-full').style.display = 'inline'; document.getElementById('2103.06287v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2103.06287v2-abstract-full" style="display: none;"> The superconducting TMD 4Hb-TaS$_2$ consists of alternating layers of H and T structures, which in their bulk form are metallic and Mott-insulating, respectively. Recently, this compound has been proposed as a candidate chiral superconductor, due to an observed enhancement of the muon spin relaxation at $T_c$. 4Hb-TaS$_2$ also exhibits a puzzling $T$-linear specific heat at low temperatures, which is unlikely to be caused by disorder. Elucidating the origin of this behavior is an essential step in discerning the true nature of the superconducting ground state. Here, we propose a simple model that attributes the $T$-linear specific heat to the emergence of a robust multi-band gapless superconducting state. We show that an extended regime of gapless superconductivity naturally appears when the pair-breaking scattering rate on distinct Fermi-surface pockets differs significantly, and the pairing interaction is predominantly intra-pocket. Using a tight-binding model derived from first-principle calculations, we show that the pair-breaking scattering rate promoted by slow magnetic fluctuations on the T layers, which arise from proximity to a Mott transition, can be significantly different in the various H-layer dominated Fermi pockets depending on their hybridization with T-layer states. Thus, our results suggest that the ground state of 4Hb-TaS$_2$ consists of Fermi pockets displaying gapless superconductivity, which are shunted by superconducting Fermi pockets that are nearly decoupled from the T-layers. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2103.06287v2-abstract-full').style.display = 'none'; document.getElementById('2103.06287v2-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 March, 2021; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 10 March, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 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">15 pages, 5 figures, two appendices</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 103, 224522 (2021) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2103.03982">arXiv:2103.03982</a> <span> [<a href="https://arxiv.org/pdf/2103.03982">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.1c00966">10.1021/acs.nanolett.1c00966 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Direct observation and consequences of dopant segregation inside and outside dislocation cores in perovskite BaSnO3 </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Yun%2C+H">Hwanhui Yun</a>, <a href="/search/cond-mat?searchtype=author&query=Prakash%2C+A">Abhinav Prakash</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Jalan%2C+B">Bharat Jalan</a>, <a href="/search/cond-mat?searchtype=author&query=Mkhoyan%2C+K+A">K. Andre Mkhoyan</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="2103.03982v1-abstract-short" style="display: inline;"> Distinct dopant behaviors inside and outside dislocation cores are identified by atomic-resolution electron microscopy in perovskite BaSnO3 with considerable consequences on local atomic and electronic structures. Driven by elastic strain, when A-site designated La dopants segregate near a dislocation core, the dopant atoms accumulate at the Ba sites in compressively strained regions. This trigger… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2103.03982v1-abstract-full').style.display = 'inline'; document.getElementById('2103.03982v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2103.03982v1-abstract-full" style="display: none;"> Distinct dopant behaviors inside and outside dislocation cores are identified by atomic-resolution electron microscopy in perovskite BaSnO3 with considerable consequences on local atomic and electronic structures. Driven by elastic strain, when A-site designated La dopants segregate near a dislocation core, the dopant atoms accumulate at the Ba sites in compressively strained regions. This triggers formation of Ba-vacancies adjacent to the core atomic sites resulting in reconstruction of the core. Notwithstanding the presence of extremely large tensile strain fields, when La atoms segregate inside the dislocation core, they become B-site dopants, replacing Sn atoms and compensating the positive charge of the core oxygen vacancies. Electron energy-loss spectroscopy shows that the local electronic structure of these dislocations changes dramatically due to the segregation of the dopants inside and around the core ranging from formation of strong La-O hybridized electronic states near the conduction band minimum to insulator-to-metal transition. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2103.03982v1-abstract-full').style.display = 'none'; document.getElementById('2103.03982v1-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 March, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2021. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2102.01542">arXiv:2102.01542</a> <span> [<a href="https://arxiv.org/pdf/2102.01542">pdf</a>, <a href="https://arxiv.org/format/2102.01542">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/10.1103/PhysRevMaterials.5.024407">10.1103/PhysRevMaterials.5.024407 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> First-principles characterization of the magnetic properties of Cu$_2$(OH)$_3$Br </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Gautreau%2C+D+M">Dominique M. Gautreau</a>, <a href="/search/cond-mat?searchtype=author&query=Saha%2C+A">Amartyajyoti Saha</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</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="2102.01542v1-abstract-short" style="display: inline;"> Low dimensional spin-1/2 transition metal oxides and oxyhalides continue to be at the forefront of research investigating nonclassical phases such as quantum spin liquids. In this study, we examine the magnetic properties of the oxyhalide $\text{Cu}_2\text{(OH)}_3\text{Br}$ in the botallackite structure using first-principles density functional theory, linear spin-wave theory, and exact diagonaliz… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2102.01542v1-abstract-full').style.display = 'inline'; document.getElementById('2102.01542v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2102.01542v1-abstract-full" style="display: none;"> Low dimensional spin-1/2 transition metal oxides and oxyhalides continue to be at the forefront of research investigating nonclassical phases such as quantum spin liquids. In this study, we examine the magnetic properties of the oxyhalide $\text{Cu}_2\text{(OH)}_3\text{Br}$ in the botallackite structure using first-principles density functional theory, linear spin-wave theory, and exact diagonalization calculations. This quasi-2D system consists of $\text{Cu}^{2+}$ $\mathrm{S} = 1/2$ moments arranged on a distorted triangular lattice. Our exact diagonalization calculations, which rely on a first-principles-based magnetic model, generate spectral functions consistent with inelastic neutron scattering (INS) data. By performing computational experiments to disentangle the chemical and steric effects of the halide ions, we find that the dominant effect of the halogen ions is steric in the $\text{Cu}_2\text{(OH)}_3\text{X}$ series of compounds. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2102.01542v1-abstract-full').style.display = 'none'; document.getElementById('2102.01542v1-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 February, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2021. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Mat. 5, 024407 (2021) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2101.05301">arXiv:2101.05301</a> <span> [<a href="https://arxiv.org/pdf/2101.05301">pdf</a>, <a href="https://arxiv.org/format/2101.05301">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.104.075101">10.1103/PhysRevB.104.075101 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Prediction of Double-Weyl Points in the Iron-Based Superconductor CaKFe$_4$As$_4$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Heinsdorf%2C+N">N. Heinsdorf</a>, <a href="/search/cond-mat?searchtype=author&query=Christensen%2C+M+H">M. H. Christensen</a>, <a href="/search/cond-mat?searchtype=author&query=Iraola%2C+M">M. Iraola</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+S">S. Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Yang%2C+F">F. Yang</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">T. Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Batista%2C+C+D">C. D. Batista</a>, <a href="/search/cond-mat?searchtype=author&query=Valent%C3%AD%2C+R">R. Valent铆</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">R. M. Fernandes</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="2101.05301v1-abstract-short" style="display: inline;"> Employing a combination of symmetry analysis, low-energy modeling, and ab initio simulations, we predict the presence of magnetic-field-induced Weyl points close to the Fermi level in CaKFe$_4$As$_4$. Depending on the relative strengths of the magnetic field and of the spin-orbit coupling, the Weyl fermions can carry a topological charge of $\pm1$ or $\pm2$, making CaKFe$_4$As$_4$ a rare realizati… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2101.05301v1-abstract-full').style.display = 'inline'; document.getElementById('2101.05301v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2101.05301v1-abstract-full" style="display: none;"> Employing a combination of symmetry analysis, low-energy modeling, and ab initio simulations, we predict the presence of magnetic-field-induced Weyl points close to the Fermi level in CaKFe$_4$As$_4$. Depending on the relative strengths of the magnetic field and of the spin-orbit coupling, the Weyl fermions can carry a topological charge of $\pm1$ or $\pm2$, making CaKFe$_4$As$_4$ a rare realization of a double-Weyl semimetal. We further predict experimental manifestations of these Weyl points, both in bulk properties, such as the anomalous Hall effect, and in surface properties, such as the emergence of prominent Fermi arcs. Because CaKFe$_4$As$_4$ displays unconventional fully-gapped superconductivity below 30 K, our findings open a novel route to investigate the interplay between superconductivity and Weyl fermions. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2101.05301v1-abstract-full').style.display = 'none'; document.getElementById('2101.05301v1-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> 13 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">Journal ref:</span> Phys. Rev. B 104, 075101 (2021) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2009.12486">arXiv:2009.12486</a> <span> [<a href="https://arxiv.org/pdf/2009.12486">pdf</a>, <a href="https://arxiv.org/format/2009.12486">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/s41524-020-00436-x">10.1038/s41524-020-00436-x <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Suppressing The Ferroelectric Switching Barrier in Hybrid Improper Ferroelectrics </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Li%2C+S">Shutong Li</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</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="2009.12486v1-abstract-short" style="display: inline;"> Integration of ferroelectric materials into novel technological applications requires low coercive field materials, and consequently, design strategies to reduce the ferroelectric switching barriers. In this first principles study, we show that biaxial strain, which has a strong effect on the ferroelectric ground states, can also be used to tune the switching barrier of hybrid improper ferroelectr… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2009.12486v1-abstract-full').style.display = 'inline'; document.getElementById('2009.12486v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2009.12486v1-abstract-full" style="display: none;"> Integration of ferroelectric materials into novel technological applications requires low coercive field materials, and consequently, design strategies to reduce the ferroelectric switching barriers. In this first principles study, we show that biaxial strain, which has a strong effect on the ferroelectric ground states, can also be used to tune the switching barrier of hybrid improper ferroelectric Ruddlesden-Popper oxides. We identify the region of the strain -- tolerance factor phase diagram where this intrinsic barrier is suppressed, and show that it can be explained in relation to strain induced phase transitions to nonpolar phases. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2009.12486v1-abstract-full').style.display = 'none'; document.getElementById('2009.12486v1-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, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2020. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> npj Comput. Mater. 6, 168 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2009.11489">arXiv:2009.11489</a> <span> [<a href="https://arxiv.org/pdf/2009.11489">pdf</a>, <a href="https://arxiv.org/format/2009.11489">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/10.1103/PhysRevB.103.045134">10.1103/PhysRevB.103.045134 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Electronic correlations in the semiconducting half-Heusler compound FeVSb </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Shourov%2C+E+H">Estiaque H. Shourov</a>, <a href="/search/cond-mat?searchtype=author&query=Strohbeen%2C+P+J">Patrick J. Strohbeen</a>, <a href="/search/cond-mat?searchtype=author&query=Du%2C+D">Dongxue Du</a>, <a href="/search/cond-mat?searchtype=author&query=Sharan%2C+A">Abhishek Sharan</a>, <a href="/search/cond-mat?searchtype=author&query=de+Lima%2C+F+C">Felipe C. de Lima</a>, <a href="/search/cond-mat?searchtype=author&query=Rodolakis%2C+F">Fanny Rodolakis</a>, <a href="/search/cond-mat?searchtype=author&query=McChesney%2C+J">Jessica McChesney</a>, <a href="/search/cond-mat?searchtype=author&query=Yannello%2C+V">Vincent Yannello</a>, <a href="/search/cond-mat?searchtype=author&query=Janotti%2C+A">Anderson Janotti</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Kawasaki%2C+J+K">Jason K. Kawasaki</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="2009.11489v2-abstract-short" style="display: inline;"> Electronic correlations are crucial to the low energy physics of metallic systems with localized $d$ and $f$ states; however, their effect on band insulators and semiconductors is typically negligible. Here, we measure the electronic structure of the half-Heusler compound FeVSb, a band insulator with filled shell configuration of 18 valence electrons per formula unit ($s^2 p^6 d^{10}$). Angle-reso… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2009.11489v2-abstract-full').style.display = 'inline'; document.getElementById('2009.11489v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2009.11489v2-abstract-full" style="display: none;"> Electronic correlations are crucial to the low energy physics of metallic systems with localized $d$ and $f$ states; however, their effect on band insulators and semiconductors is typically negligible. Here, we measure the electronic structure of the half-Heusler compound FeVSb, a band insulator with filled shell configuration of 18 valence electrons per formula unit ($s^2 p^6 d^{10}$). Angle-resolved photoemission spectroscopy (ARPES) reveals a mass renormalization of $m^{*}/m_{bare}= 1.4$, where $m^{*}$ is the measured effective mass and $m_{bare}$ is the mass from density functional theory (DFT) calculations with no added on-site Coulomb repulsion. Our measurements are in quantitative agreement with dynamical mean field theory (DMFT) calculations, highlighting the many-body origin of the mass renormalization. This mass renormalization lies in dramatic contrast to other filled shell intermetallics, including the thermoelectric materials CoTiSb and NiTiSn; and has a similar origin to that in FeSi, where Hund's coupling induced fluctuations across the gap can explain a dynamical self-energy and correlations. Our work calls for a re-thinking of the role of correlations and Hund's coupling in intermetallic band insulators. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2009.11489v2-abstract-full').style.display = 'none'; document.getElementById('2009.11489v2-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 September, 2020; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 24 September, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2020. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 103, 045134 (2021) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2006.13195">arXiv:2006.13195</a> <span> [<a href="https://arxiv.org/pdf/2006.13195">pdf</a>, <a href="https://arxiv.org/format/2006.13195">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/PhysRevResearch.2.033156">10.1103/PhysRevResearch.2.033156 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Cation Order Control of Correlations in Double Perovskite Sr$_2$VNbO$_6$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Paul%2C+A">Arpita Paul</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</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="2006.13195v1-abstract-short" style="display: inline;"> Double perovskites extend the design space for new materials, and they often host phenomena that don't exist in their parent perovskite compounds. Here, we present a detailed first principles study of the correlated double perovskite Sr$_2$VNbO$_6$, where inter-cationic charge transfer and strength of electronic correlations depend strongly on the cation order. By using Density Functional Theory +… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2006.13195v1-abstract-full').style.display = 'inline'; document.getElementById('2006.13195v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2006.13195v1-abstract-full" style="display: none;"> Double perovskites extend the design space for new materials, and they often host phenomena that don't exist in their parent perovskite compounds. Here, we present a detailed first principles study of the correlated double perovskite Sr$_2$VNbO$_6$, where inter-cationic charge transfer and strength of electronic correlations depend strongly on the cation order. By using Density Functional Theory + Embedded Dynamical Mean Field Theory, we show that this compound has a completely different electronic structure than either of its parent compounds despite V and Nb being from the same group in the periodic table. We explain how the electronic correlations' effect on the crystal structural parameters determines on which side of the Hund's metal-Mott insulator transition the material is. Our results demonstrate the emergence of Hund's metallic behavior in a double perovskite that has $d^1$ parents, and underlines the importance of electronic correlation effects on the crystal structure. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2006.13195v1-abstract-full').style.display = 'none'; document.getElementById('2006.13195v1-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 June, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2020. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Research 2, 033156 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2006.10922">arXiv:2006.10922</a> <span> [<a href="https://arxiv.org/pdf/2006.10922">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> </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.125.037204">10.1103/PhysRevLett.125.037204 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Coexistence and interaction of spinons and magnons in an antiferromagnet with alternating antiferromagnetic and ferromagnetic quantum spin chains </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+H">H. Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Zhao%2C+Z">Z. Zhao</a>, <a href="/search/cond-mat?searchtype=author&query=Gautreau%2C+D">D. Gautreau</a>, <a href="/search/cond-mat?searchtype=author&query=Raczkowski%2C+M">M. Raczkowski</a>, <a href="/search/cond-mat?searchtype=author&query=Saha%2C+A">A. Saha</a>, <a href="/search/cond-mat?searchtype=author&query=Garlea%2C+V+O">V. O. Garlea</a>, <a href="/search/cond-mat?searchtype=author&query=Cao%2C+H">H. Cao</a>, <a href="/search/cond-mat?searchtype=author&query=Hong%2C+T">T. Hong</a>, <a href="/search/cond-mat?searchtype=author&query=Jeschke%2C+H+O">H. O. Jeschke</a>, <a href="/search/cond-mat?searchtype=author&query=Mahanti%2C+S+D">Subhendra D. Mahanti</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">T. Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Assaad%2C+F+F">F. F. Assaad</a>, <a href="/search/cond-mat?searchtype=author&query=Ke%2C+X">X. Ke</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="2006.10922v2-abstract-short" style="display: inline;"> In conventional quasi-one-dimensional antiferromagnets with quantum spins, magnetic excitations are carried by either magnons or spinons in different energy regimes: they do not coexist independently, nor could they interact with each other. In this Letter, by combining inelastic neutron scattering, quantum Monte Carlo simulations and Random Phase Approximation calculations, we report the discover… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2006.10922v2-abstract-full').style.display = 'inline'; document.getElementById('2006.10922v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2006.10922v2-abstract-full" style="display: none;"> In conventional quasi-one-dimensional antiferromagnets with quantum spins, magnetic excitations are carried by either magnons or spinons in different energy regimes: they do not coexist independently, nor could they interact with each other. In this Letter, by combining inelastic neutron scattering, quantum Monte Carlo simulations and Random Phase Approximation calculations, we report the discovery and discuss the physics of the coexistence of magnons and spinons and their interactions in Botallackite-Cu2(OH)3Br. This is a unique quantum antiferromagnet consisting of alternating ferromagnetic and antiferromagnetic Spin-1/2 chains with weak inter-chain couplings. Our study presents a new paradigm where one can study the interaction between two different types of magnetic quasiparticles, magnons and spinons. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2006.10922v2-abstract-full').style.display = 'none'; document.getElementById('2006.10922v2-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 July, 2020; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 18 June, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 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">Accepted by PRL</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, 037204 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2002.01996">arXiv:2002.01996</a> <span> [<a href="https://arxiv.org/pdf/2002.01996">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="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.101.180409">10.1103/PhysRevB.101.180409 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Multiferroic behavior confined by symmetry in EuTiO3 films </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Ryan%2C+P+J">P. J. Ryan</a>, <a href="/search/cond-mat?searchtype=author&query=Sterbinsky%2C+G+E">G. E. Sterbinsky</a>, <a href="/search/cond-mat?searchtype=author&query=Choi%2C+Y">Y. Choi</a>, <a href="/search/cond-mat?searchtype=author&query=Woicik%2C+J+C">J. C. Woicik</a>, <a href="/search/cond-mat?searchtype=author&query=Zhu%2C+L">Leyi Zhu</a>, <a href="/search/cond-mat?searchtype=author&query=Jiang%2C+J+S">J. S. Jiang</a>, <a href="/search/cond-mat?searchtype=author&query=Lee%2C+J">J-H. Lee</a>, <a href="/search/cond-mat?searchtype=author&query=Schlom%2C+D+G">D. G. Schlom</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">T. Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Brown%2C+S+D">S. D. Brown</a>, <a href="/search/cond-mat?searchtype=author&query=Thompson%2C+P+B+J">P. B. J. Thompson</a>, <a href="/search/cond-mat?searchtype=author&query=Normile%2C+P+S">P. S. Normile</a>, <a href="/search/cond-mat?searchtype=author&query=Lang%2C+J">J. Lang</a>, <a href="/search/cond-mat?searchtype=author&query=Kim%2C+J+-">J. -W. Kim</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="2002.01996v1-abstract-short" style="display: inline;"> We have elucidated the spin, lattice, charge and orbital coupling mechanism underlying the multiferroic character in tensile strained EuTiO3 films. Symmetry determined by oxygen octahedral tilting shapes the hybridization between the Eu 4f and Ti 3d orbitals and this inhibits predicted Ti displacement proper ferroelectricity. Instead, phonon softening emerges at low temperatures within the pseudo-… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2002.01996v1-abstract-full').style.display = 'inline'; document.getElementById('2002.01996v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2002.01996v1-abstract-full" style="display: none;"> We have elucidated the spin, lattice, charge and orbital coupling mechanism underlying the multiferroic character in tensile strained EuTiO3 films. Symmetry determined by oxygen octahedral tilting shapes the hybridization between the Eu 4f and Ti 3d orbitals and this inhibits predicted Ti displacement proper ferroelectricity. Instead, phonon softening emerges at low temperatures within the pseudo-cube (110) plane, orthogonal to the anticipated ferroelectric polarization symmetry. Additionally, the magnetic anisotropy is determined by orbital distortion through hybridization between the Ti 3d and typically isotropic Eu2+ 4f. This unique scenario demonstrates the critical role symmetry plays in the coupling of order parameters defining multiferroic behaviour. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2002.01996v1-abstract-full').style.display = 'none'; document.getElementById('2002.01996v1-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 February, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 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">11 pages, 3 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 101, 180409 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2001.07319">arXiv:2001.07319</a> <span> [<a href="https://arxiv.org/pdf/2001.07319">pdf</a>, <a href="https://arxiv.org/format/2001.07319">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/10.1103/PhysRevMaterials.4.054405">10.1103/PhysRevMaterials.4.054405 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Contrasting Ferromagnetism in Pyrite FeS$_2$ Induced by Chemical Doping versus Electrostatic Gating </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Day-Roberts%2C+E">Ezra Day-Roberts</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Fernandes%2C+R+M">Rafael M. Fernandes</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="2001.07319v1-abstract-short" style="display: inline;"> Recent advances in electrostatic gating provide a novel way to modify the carrier concentration in materials via electrostatic means instead of chemical doping, thus minimizing the impurity scattering. Here, we use first-principles Density Functional Theory combined with a tight-binding approach to compare and contrast the effects of electrostatic gating and Co chemical doping on the ferromagnetic… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2001.07319v1-abstract-full').style.display = 'inline'; document.getElementById('2001.07319v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2001.07319v1-abstract-full" style="display: none;"> Recent advances in electrostatic gating provide a novel way to modify the carrier concentration in materials via electrostatic means instead of chemical doping, thus minimizing the impurity scattering. Here, we use first-principles Density Functional Theory combined with a tight-binding approach to compare and contrast the effects of electrostatic gating and Co chemical doping on the ferromagnetic transition of FeS$_2$, a transition metal disulfide with the pyrite structure. Using tight-binding parameters obtained from maximally-localized Wannier functions, we calculate the magnetic susceptibility across a wide doping range. We find that electrostatic gating requires a higher electron concentration than the equivalent in Co doping to induce ferromagnetism via a Stoner-like mechanism. We attribute this behavior to the formation of a narrow Co band near the bottom of the conduction band under chemical doping, which is absent in the electrostatic gating case. Our results reveal that the effects of electrostatic gating go beyond a simple rigid band shift, and highlight the importance of the changes in the crystal structure promoted by gating. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2001.07319v1-abstract-full').style.display = 'none'; document.getElementById('2001.07319v1-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, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2020. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Materials 4, 054405 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1909.02020">arXiv:1909.02020</a> <span> [<a href="https://arxiv.org/pdf/1909.02020">pdf</a>, <a href="https://arxiv.org/format/1909.02020">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/PhysRevLett.124.167203">10.1103/PhysRevLett.124.167203 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Spin--lattice coupling and the emergence of the trimerized phase in the $S=1$ Kagome antiferromagnet Na$_2$Ti$_3$Cl$_8$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Paul%2C+A">Arpita Paul</a>, <a href="/search/cond-mat?searchtype=author&query=Chung%2C+C">Chia-Min Chung</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Changlani%2C+H+J">Hitesh J. Changlani</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="1909.02020v1-abstract-short" style="display: inline;"> Spin-1 antiferromagnets are abundant in nature, but few theories or results exist to understand their general properties and behavior, particularly in situations when geometric frustration is present. Here we study the $S=1$ Kagome compound Na$_2$Ti$_3$Cl$_8$ using a combination of Density Functional Theory, Exact Diagonalization, and Density Matrix Renormalization Group methods to achieve a first… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1909.02020v1-abstract-full').style.display = 'inline'; document.getElementById('1909.02020v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1909.02020v1-abstract-full" style="display: none;"> Spin-1 antiferromagnets are abundant in nature, but few theories or results exist to understand their general properties and behavior, particularly in situations when geometric frustration is present. Here we study the $S=1$ Kagome compound Na$_2$Ti$_3$Cl$_8$ using a combination of Density Functional Theory, Exact Diagonalization, and Density Matrix Renormalization Group methods to achieve a first principles supported explanation of exotic magnetic phases in this compound. We find that the effective magnetic Hamiltonian includes essential non-Heisenberg terms that do not stem from spin-orbit coupling, and both trimerized and spin-nematic magnetic phases are relevant. The experimentally observed structural transition to a breathing Kagome phase is driven by spin--lattice coupling, which favors the trimerized magnetic phase against the quadrupolar one. We thus show that lattice effects can be necessary to understand the magnetism in frustrated magnetic compounds, and surmise that Na$_2$Ti$_3$Cl$_8$ is a compound which cannot be understood from only electronic or only lattice Hamiltonians, very much like VO$_2$. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1909.02020v1-abstract-full').style.display = 'none'; document.getElementById('1909.02020v1-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> 4 September, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 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">6 pages, 4 figures. 9 pages of supplementary material with 10 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. 124, 167203 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1907.09860">arXiv:1907.09860</a> <span> [<a href="https://arxiv.org/pdf/1907.09860">pdf</a>, <a href="https://arxiv.org/format/1907.09860">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="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/PhysRevMaterials.3.085001">10.1103/PhysRevMaterials.3.085001 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Strain Tuning of Plasma Frequency in Vanadate, Niobate, and Molybdate Perovskite Oxides </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Paul%2C+A">Arpita Paul</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</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="1907.09860v1-abstract-short" style="display: inline;"> A novel approach for finding new transparent conductors involves taking advantage of electronic correlations in metallic transition metal oxides, such as SrVO$_3$, to enhance the electronic effective mass and suppress the plasma frequency ($蠅_P$) to infrared. Success of this approach relies on finding a compound with the right electron effective mass and quasiparticle weight $Z$. Biaxial strain ca… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1907.09860v1-abstract-full').style.display = 'inline'; document.getElementById('1907.09860v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1907.09860v1-abstract-full" style="display: none;"> A novel approach for finding new transparent conductors involves taking advantage of electronic correlations in metallic transition metal oxides, such as SrVO$_3$, to enhance the electronic effective mass and suppress the plasma frequency ($蠅_P$) to infrared. Success of this approach relies on finding a compound with the right electron effective mass and quasiparticle weight $Z$. Biaxial strain can in principle be a fruitful way to manipulate the electronic properties of materials to tune both of these quantities. In this study, we elucidate the behavior of the electronic properties of early transition metal oxides SrVO$_3$, SrNbO$_3$, and SrMoO$_3$ under strain, using first principles density functional theory and dynamical mean field theory. We show that strain is not an effective way to manipulate the plasma frequency, but dimensionality of the crystal structure and origin of electronic correlations strongly affect the trends in both $蠅_P$ and $Z$. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1907.09860v1-abstract-full').style.display = 'none'; document.getElementById('1907.09860v1-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 July, 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">Journal ref:</span> Phys. Rev. Materials 3, 085001 (2019) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1907.09392">arXiv:1907.09392</a> <span> [<a href="https://arxiv.org/pdf/1907.09392">pdf</a>, <a href="https://arxiv.org/format/1907.09392">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/s41535-019-0184-x">10.1038/s41535-019-0184-x <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Spin-lattice and electron-phonon coupling in 3$d$/5$d$ hybrid Sr$_3$NiIrO$_6$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=O%27Neal%2C+K+R">Kenneth R. O'Neal</a>, <a href="/search/cond-mat?searchtype=author&query=Paul%2C+A">Arpita Paul</a>, <a href="/search/cond-mat?searchtype=author&query=al-Wahish%2C+A">Amal al-Wahish</a>, <a href="/search/cond-mat?searchtype=author&query=Hughey%2C+K+D">Kendall D. Hughey</a>, <a href="/search/cond-mat?searchtype=author&query=Blockmon%2C+A+L">Avery L. Blockmon</a>, <a href="/search/cond-mat?searchtype=author&query=Luo%2C+X">Xuan Luo</a>, <a href="/search/cond-mat?searchtype=author&query=Cheong%2C+S">Sang-Wook Cheong</a>, <a href="/search/cond-mat?searchtype=author&query=Zapf%2C+V+S">Vivien S. Zapf</a>, <a href="/search/cond-mat?searchtype=author&query=Topping%2C+C+V">Craig V. Topping</a>, <a href="/search/cond-mat?searchtype=author&query=Singleton%2C+J">John Singleton</a>, <a href="/search/cond-mat?searchtype=author&query=Ozerov%2C+M">Mykhalo Ozerov</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</a>, <a href="/search/cond-mat?searchtype=author&query=Musfeldt%2C+J+L">Janice L. Musfeldt</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="1907.09392v1-abstract-short" style="display: inline;"> While 3$d$-containing materials display strong electron correlations, narrow band widths, and robust magnetism, 5$d$ systems are recognized for strong spin-orbit coupling, increased hybridization, and more diffuse orbitals. Combining these properties leads to novel behavior. Sr$_3$NiIrO$_6$, for example, displays complex magnetism and ultra-high coercive fields - up to an incredible 55~T. Here, we… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1907.09392v1-abstract-full').style.display = 'inline'; document.getElementById('1907.09392v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1907.09392v1-abstract-full" style="display: none;"> While 3$d$-containing materials display strong electron correlations, narrow band widths, and robust magnetism, 5$d$ systems are recognized for strong spin-orbit coupling, increased hybridization, and more diffuse orbitals. Combining these properties leads to novel behavior. Sr$_3$NiIrO$_6$, for example, displays complex magnetism and ultra-high coercive fields - up to an incredible 55~T. Here, we combine infrared and optical spectroscopies with high-field magnetization and first principles calculations to explore the fundamental excitations of the lattice and related coupling processes including spin-lattice and electron-phonon mechanisms. Magneto-infrared spectroscopy reveals spin-lattice coupling of three phonons that modulate the Ir environment to reduce the energy required to modify the spin arrangement. While these modes primarily affect exchange within the chains, analysis also uncovers important inter-chain motion. This provides a mechanism by which inter-chain interactions can occur in the developing model for ultra-high coercivity. At the same time, analysis of the on-site Ir$^{4+}$ excitations reveals vibronic coupling and extremely large crystal field parameters that lead to a t$_{2g}$-derived low-spin state for Ir. These findings highlight the spin-charge-lattice entanglement in Sr$_3$NiIrO$_6$ and suggest that similar interactions may take place in other 3$d$/5$d$ hybrids. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1907.09392v1-abstract-full').style.display = 'none'; document.getElementById('1907.09392v1-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 July, 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">Journal ref:</span> npj Quantum Materials 4, 48 (2019) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1809.09246">arXiv:1809.09246</a> <span> [<a href="https://arxiv.org/pdf/1809.09246">pdf</a>, <a href="https://arxiv.org/ps/1809.09246">ps</a>, <a href="https://arxiv.org/format/1809.09246">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/10.1146/annurev-matsci-070218-121825">10.1146/annurev-matsci-070218-121825 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Applications of DFT+DMFT in Materials Science </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Paul%2C+A">Arpita Paul</a>, <a href="/search/cond-mat?searchtype=author&query=Birol%2C+T">Turan Birol</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="1809.09246v2-abstract-short" style="display: inline;"> First principles methods can provide insight into materials that is otherwise impossible to acquire. Density Functional Theory (DFT) has been the first principles method of choice for numerous applications, but it falls short of predicting the properties of correlated materials. First principles Density Functional Theory + Dynamical Mean Field Theory (DFT+DMFT) is a powerful tool that can address… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1809.09246v2-abstract-full').style.display = 'inline'; document.getElementById('1809.09246v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1809.09246v2-abstract-full" style="display: none;"> First principles methods can provide insight into materials that is otherwise impossible to acquire. Density Functional Theory (DFT) has been the first principles method of choice for numerous applications, but it falls short of predicting the properties of correlated materials. First principles Density Functional Theory + Dynamical Mean Field Theory (DFT+DMFT) is a powerful tool that can address these shortcomings of DFT when applied to correlated metals. In this brief review, which is aimed at non-experts, we review the basics and some applications of DFT+DMFT. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1809.09246v2-abstract-full').style.display = 'none'; document.getElementById('1809.09246v2-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 December, 2018; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 24 September, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Annual Review of Materials Research 49, 31 (2019) </p> </li> </ol> <nav class="pagination is-small is-centered breathe-horizontal" role="navigation" aria-label="pagination"> <a href="" class="pagination-previous 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