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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=Sankar%2C+R&start=50" class="pagination-next" >Next </a> <ul class="pagination-list"> <li> <a href="/search/?searchtype=author&query=Sankar%2C+R&start=0" class="pagination-link is-current" aria-label="Goto page 1">1 </a> </li> <li> <a href="/search/?searchtype=author&query=Sankar%2C+R&start=50" class="pagination-link " aria-label="Page 2" aria-current="page">2 </a> </li> <li> <a href="/search/?searchtype=author&query=Sankar%2C+R&start=100" class="pagination-link " aria-label="Page 3" aria-current="page">3 </a> </li> </ul> </nav> <ol class="breathe-horizontal" start="1"> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2502.02791">arXiv:2502.02791</a> <span> [<a href="https://arxiv.org/pdf/2502.02791">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="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.111.085101">10.1103/PhysRevB.111.085101 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Strong Long-Wave Infrared Optical Response in a Topological Semiconductor with a Mexican Hat Band Structure </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Polking%2C+M+J">Mark J. Polking</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+H">Haowei Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Grossklaus%2C+K">Kevin Grossklaus</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+J">Ju Li</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="2502.02791v1-abstract-short" style="display: inline;"> Light sources and photodetectors operating in the far- to mid-infrared (FIR/MIR) band ($8$-$12~\rm 渭m$, $0.1$-$0.15~\rm eV$) remain relatively poorly developed compared to their counterparts operating in the visible and near-infrared ranges, despite extensive application potential for thermal imaging, standoff sensing, and other technologies. This is attributable in part to the lack of narrow-gap… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2502.02791v1-abstract-full').style.display = 'inline'; document.getElementById('2502.02791v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2502.02791v1-abstract-full" style="display: none;"> Light sources and photodetectors operating in the far- to mid-infrared (FIR/MIR) band ($8$-$12~\rm 渭m$, $0.1$-$0.15~\rm eV$) remain relatively poorly developed compared to their counterparts operating in the visible and near-infrared ranges, despite extensive application potential for thermal imaging, standoff sensing, and other technologies. This is attributable in part to the lack of narrow-gap materials ($<0.1~\rm eV$) with high optical gain and absorption. In this work, a narrow-gap semiconductor, $\rm Pb_{0.7}Sn_{0.3}Se$, is demonstrated to exhibit an optical response $>10\times$ larger than that of $\rm Hg_{x}Cd_{1-x}Te$ (MCT), the dominant material for FIR/MIR photodetectors. A previous theoretical investigation indicated that chalcogen $p$ and metal $d$ band inversion in this material creates a Mexican hat band structure (MHBS), which results in a dramatic increase in the joint density of states at the optical transition edge compared to typical semiconductors. This prediction is experimentally validated here using single-crystal specimens of $\rm Pb_{0.7}Sn_{0.3}Se$ measured using temperature-dependent spectroscopic ellipsometry over a wavelength range of $1.7$-$20~\rm 渭m$ ($0.73$-$0.062~\rm eV$). These measurements demonstrate a large enhancement in extinction coefficient and refractive index characteristic of a MHBS in the vicinity of the absorption edge, in agreement with theoretical predictions. The realization of topological semiconductors with a MHBS is expected to lead to high-efficiency detectors operating in the FIR/MID range. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2502.02791v1-abstract-full').style.display = 'none'; document.getElementById('2502.02791v1-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 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">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. B 111, 085101 (2025) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2501.06272">arXiv:2501.06272</a> <span> [<a href="https://arxiv.org/pdf/2501.06272">pdf</a>, <a href="https://arxiv.org/format/2501.06272">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="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.111.024502">10.1103/PhysRevB.111.024502 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Effects of disorder on the quantum transport properties in topologically nontrivial metal PbTaSe$_{2}$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Sun%2C+L">Longfei Sun</a>, <a href="/search/cond-mat?searchtype=author&query=Sun%2C+Y">Yue Sun</a>, <a href="/search/cond-mat?searchtype=author&query=Hou%2C+Q">Qiang Hou</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Kalaivanan%2C+R">R. Kalaivanan</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+X">Xiaofeng Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Shi%2C+Z">Zhixiang Shi</a>, <a href="/search/cond-mat?searchtype=author&query=Tamegai%2C+T">Tsuyoshi Tamegai</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="2501.06272v1-abstract-short" style="display: inline;"> Weak antilocalization (WAL), an increase in the electrical conductivity at low temperatures associated with the suppression of electron localization due to quantum interference effects, is often observed in topological materials. In this study, we report the observation of WAL in topologically nontrivial metal PbTaSe$_{2}$ at low temperatures. In the pristine sample, we identified the presence of… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2501.06272v1-abstract-full').style.display = 'inline'; document.getElementById('2501.06272v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2501.06272v1-abstract-full" style="display: none;"> Weak antilocalization (WAL), an increase in the electrical conductivity at low temperatures associated with the suppression of electron localization due to quantum interference effects, is often observed in topological materials. In this study, we report the observation of WAL in topologically nontrivial metal PbTaSe$_{2}$ at low temperatures. In the pristine sample, we identified the presence of WAL, which is attributed to the topologically protected backscattering. In order to investigate the influence of disorder on the WAL, we successively introduced controlled amounts of disorder by H$^{+}$-irradiation. As disorder increases, the dip-like magnetoresistance caused by WAL changes to a linear magnetoresistance(MR), and eventually to a quadratic MR as the electronic system becomes highly localized. This research unveils the significance of disorder in shaping the quantum transport characteristics of topological materials. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2501.06272v1-abstract-full').style.display = 'none'; document.getElementById('2501.06272v1-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 January, 2025; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 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">7 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. B 111, 024502 (2025) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2411.15791">arXiv:2411.15791</a> <span> [<a href="https://arxiv.org/pdf/2411.15791">pdf</a>, <a href="https://arxiv.org/format/2411.15791">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"> Ultrafast Spectroscopy of Dirac Semimetal Cd3As2 under Pressure </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Arora%2C+V">Vikas Arora</a>, <a href="/search/cond-mat?searchtype=author&query=Muthu%2C+D+V+S">D. V. S. Muthu</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Sood%2C+A+K">A K Sood</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="2411.15791v1-abstract-short" style="display: inline;"> Topological properties of a three-dimensional Dirac semimetal Cd3As2, protected by crystal rotation and time-reversal symmetry, can be tuned with the application of pressure. Ultrafast spectroscopy is a unique tool to investigate the character and time evolution of electronic states, emphasizing the signatures of transition. We designed an experimental setup for in-situ pressure-dependent ultrafas… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2411.15791v1-abstract-full').style.display = 'inline'; document.getElementById('2411.15791v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2411.15791v1-abstract-full" style="display: none;"> Topological properties of a three-dimensional Dirac semimetal Cd3As2, protected by crystal rotation and time-reversal symmetry, can be tuned with the application of pressure. Ultrafast spectroscopy is a unique tool to investigate the character and time evolution of electronic states, emphasizing the signatures of transition. We designed an experimental setup for in-situ pressure-dependent ultrafast optical pump optical probe spectroscopy of Cd3As2 using a symmetric diamond anvil cell. The fast relaxation processes show significant changes across pressure-induced phase transitions at PC1, approximately 3 GPa, and PC2, approximately 9 GPa. A new sub-picosecond time scale relaxation dynamics emerges beyond PC2. Theoretical calculations of differential reflectivity for both interband and intraband processes indicate that the negative (positive) differential reflectivity (Delta R/R) results from the interband (intraband) processes. The pressure-dependent behavior of relaxation dynamics amplitudes beyond PC1 emphasized the necessity of incorporating quadratic band opening in the calculations, explaining the transition of Cd3As2 from a Dirac semimetal to a semiconducting phase. The time evolution of differential reflectivity is calculated using the electronic temperature as a function of time, as provided by the two-temperature model, which fits the experimental data. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2411.15791v1-abstract-full').style.display = 'none'; document.getElementById('2411.15791v1-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> <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, 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/2409.05661">arXiv:2409.05661</a> <span> [<a href="https://arxiv.org/pdf/2409.05661">pdf</a>, <a href="https://arxiv.org/format/2409.05661">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.110.L140402">10.1103/PhysRevB.110.L140402 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Signatures of a Quantum Critical Endpoint in the Kitaev Candidate Na$_2$Co$_2$TeO$_6$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Arneth%2C+J">J. Arneth</a>, <a href="/search/cond-mat?searchtype=author&query=Choi%2C+K+-">K. -Y. Choi</a>, <a href="/search/cond-mat?searchtype=author&query=Kalaivanan%2C+R">R. Kalaivanan</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Klingeler%2C+R">R. Klingeler</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2409.05661v1-abstract-short" style="display: inline;"> The putative Kitaev material Na$_2$Co$_2$TeO$_6$ has recently been proposed to enter a quantum spin disordered state when magnetic fields are applied in parallel to the honeycomb layers. In this report we uncover signatures of a quantum critical endpoint (QCEP) associated with the assumed order-disorder transition by means of high-resolution capacitance dilatometry. At the critical field… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2409.05661v1-abstract-full').style.display = 'inline'; document.getElementById('2409.05661v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2409.05661v1-abstract-full" style="display: none;"> The putative Kitaev material Na$_2$Co$_2$TeO$_6$ has recently been proposed to enter a quantum spin disordered state when magnetic fields are applied in parallel to the honeycomb layers. In this report we uncover signatures of a quantum critical endpoint (QCEP) associated with the assumed order-disorder transition by means of high-resolution capacitance dilatometry. At the critical field $B_\mathrm{C} \simeq 6$~T , a sign change of the out-of-plane thermal expansion coefficient $伪_c$ indicates accumulation of entropy upon crossing the phase boundary. The proportional relationship between isothermal magnetisation and magnetostriction signals that the QCEP can be tuned by magnetic field and pressure simultaneously. The presented results expand the material classes that exhibit metamagnetic quantum criticality to honeycomb antiferromagnets with possible Kitaev interactions. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2409.05661v1-abstract-full').style.display = 'none'; document.getElementById('2409.05661v1-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 September, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2024. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">20 pages, 13 figures, submitted to 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 110, L140402 (2024) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2408.12230">arXiv:2408.12230</a> <span> [<a href="https://arxiv.org/pdf/2408.12230">pdf</a>, <a href="https://arxiv.org/format/2408.12230">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"> Tuning THz magnons in a mixed van-der-Waals antiferromagnet </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Mardele%2C+F+L">F. Le Mardele</a>, <a href="/search/cond-mat?searchtype=author&query=Mohelsky%2C+I">I. Mohelsky</a>, <a href="/search/cond-mat?searchtype=author&query=Jana%2C+D">D. Jana</a>, <a href="/search/cond-mat?searchtype=author&query=Pawbake%2C+A">A. Pawbake</a>, <a href="/search/cond-mat?searchtype=author&query=Dzian%2C+J">J. Dzian</a>, <a href="/search/cond-mat?searchtype=author&query=Lee%2C+W+-">W. -L. Lee</a>, <a href="/search/cond-mat?searchtype=author&query=Raju%2C+K">K. Raju</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Faugeras%2C+C">C. Faugeras</a>, <a href="/search/cond-mat?searchtype=author&query=Potemski%2C+M">M. Potemski</a>, <a href="/search/cond-mat?searchtype=author&query=Zhitomirsky%2C+M+E">M. E. Zhitomirsky</a>, <a href="/search/cond-mat?searchtype=author&query=Orlita%2C+M">M. Orlita</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="2408.12230v2-abstract-short" style="display: inline;"> Alloying stands out as a pivotal technological method employed across various compounds, be they metallic, magnetic, or semiconducting, serving to fine-tune their properties to meet specific requirements. Ternary semiconductors represent a prominent example of such alloys. They offer fine-tuning of electronic bands, the band gap in particular, thus granting the technology of semiconductor heterost… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2408.12230v2-abstract-full').style.display = 'inline'; document.getElementById('2408.12230v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2408.12230v2-abstract-full" style="display: none;"> Alloying stands out as a pivotal technological method employed across various compounds, be they metallic, magnetic, or semiconducting, serving to fine-tune their properties to meet specific requirements. Ternary semiconductors represent a prominent example of such alloys. They offer fine-tuning of electronic bands, the band gap in particular, thus granting the technology of semiconductor heterostructures devices, key elements in current electronics and optoelectronics. In the realm of magnetically ordered systems, akin to electronic bands in solids, spin waves exhibit characteristic dispersion relations, featuring sizeable magnon gaps in many antiferromagnets. The engineering of the magnon gap constitutes a relevant direction in current research on antiferromagnets, aiming to leverage their distinct properties for THz technologies, spintronics, or magnonics. In this study, we showcase the tunability of the magnon gap across the THz spectral range within an alloy comprising representative semiconducting van-der-Waals antiferromagnets FePS$_3$ and NiPS$_3$. These constituents share identical in-plane crystal structures, magnetic unit cells and the direction of the magnetic anisotropy, but differ in the amplitude and sign of the latter. Altogether these attributes result in the wide tunability of the magnon gap in the Fe$_{1-x}$Ni$_x$PS$_3$ alloy in which the magnetic order is imposed by stronger, perpendicular anisotropy of iron. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2408.12230v2-abstract-full').style.display = 'none'; document.getElementById('2408.12230v2-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 November, 2024; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 22 August, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 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">6 pages, 1 figure, to be published in Phys. Rev. B</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2404.11099">arXiv:2404.11099</a> <span> [<a href="https://arxiv.org/pdf/2404.11099">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"> Interplay between magnetic and lattice excitations and emergent multiple phase transitions in MnPSe3-xSx </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Kumar%2C+D">Deepu Kumar</a>, <a href="/search/cond-mat?searchtype=author&query=Hoang%2C+N+T">Nguyen The Hoang</a>, <a href="/search/cond-mat?searchtype=author&query=Sim%2C+Y">Yumin Sim</a>, <a href="/search/cond-mat?searchtype=author&query=Choi%2C+Y">Youngsu Choi</a>, <a href="/search/cond-mat?searchtype=author&query=Raju%2C+K">Kalaivanan Raju</a>, <a href="/search/cond-mat?searchtype=author&query=Ulaganathan%2C+R+K">Rajesh Kumar Ulaganathan</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Seong%2C+M">Maeng-Je Seong</a>, <a href="/search/cond-mat?searchtype=author&query=Choi%2C+K">Kwang-Yong Choi</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="2404.11099v1-abstract-short" style="display: inline;"> The intricate interplay between spin and lattice degrees of freedom in two-dimensional magnetic materials plays a pivotal role in modifying their magnetic characteristics, engendering hybrid quasiparticles, and implementing functional devices. Herein, we present our comprehensive and in-depth investigations on magnetic and lattice excitations of MnPSe3-xSx (x = 0, 0.5, and 1.5) alloys, utilizing t… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2404.11099v1-abstract-full').style.display = 'inline'; document.getElementById('2404.11099v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2404.11099v1-abstract-full" style="display: none;"> The intricate interplay between spin and lattice degrees of freedom in two-dimensional magnetic materials plays a pivotal role in modifying their magnetic characteristics, engendering hybrid quasiparticles, and implementing functional devices. Herein, we present our comprehensive and in-depth investigations on magnetic and lattice excitations of MnPSe3-xSx (x = 0, 0.5, and 1.5) alloys, utilizing temperature- and polarization-dependent Raman scattering. Our experimental results reveal the occurrence of multiple phase transitions, evidenced by notable changes in phonon self-energy and the appearance or splitting of phonon modes. These emergent phases are tied to the development of long and short-range spin-spin correlations, as well as to spin reorientations or magnetic instabilities. Our analysis of two-magnon excitations as a function of temperature and composition showcases their hybridization with phonons whose degree weakens with increasing x. Moreover, the suppression of spin-dependent phonon intensity in chemically most-disordered MnPSe3-xSx (x = 1.5) suggests that chalcogen substitution offers a control knob of tuning spin and phonon dynamics by modulating concurrently superexchange pathways and a degree of trigonal distortions. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2404.11099v1-abstract-full').style.display = 'none'; document.getElementById('2404.11099v1-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 April, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2024. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2402.18893">arXiv:2402.18893</a> <span> [<a href="https://arxiv.org/pdf/2402.18893">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"> Direct Visualization of a Disorder Driven Electronic Smectic Phase in Dirac Nodal Line Semimetal GdSbTe </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Venkatesan%2C+B">Balaji Venkatesan</a>, <a href="/search/cond-mat?searchtype=author&query=Guan%2C+S">Syu-You Guan</a>, <a href="/search/cond-mat?searchtype=author&query=Chang%2C+J">Jen-Te Chang</a>, <a href="/search/cond-mat?searchtype=author&query=Chiu%2C+S">Shiang-Bin Chiu</a>, <a href="/search/cond-mat?searchtype=author&query=Yang%2C+P">Po-Yuan Yang</a>, <a href="/search/cond-mat?searchtype=author&query=Su%2C+C">Chih-Chuan Su</a>, <a href="/search/cond-mat?searchtype=author&query=Chang%2C+T">Tay-Rong Chang</a>, <a href="/search/cond-mat?searchtype=author&query=Raju%2C+K">Kalaivanan Raju</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Fongchaiya%2C+S">Somboon Fongchaiya</a>, <a href="/search/cond-mat?searchtype=author&query=Chu%2C+M">Ming-Wen Chu</a>, <a href="/search/cond-mat?searchtype=author&query=Chang%2C+C">Chia-Seng Chang</a>, <a href="/search/cond-mat?searchtype=author&query=Chang%2C+G">Guoqing Chang</a>, <a href="/search/cond-mat?searchtype=author&query=Lin%2C+H">Hsin Lin</a>, <a href="/search/cond-mat?searchtype=author&query=Del+Maestro%2C+A">Adrian Del Maestro</a>, <a href="/search/cond-mat?searchtype=author&query=Kao%2C+Y">Ying-Jer Kao</a>, <a href="/search/cond-mat?searchtype=author&query=Chuang%2C+T">Tien-Ming Chuang</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2402.18893v3-abstract-short" style="display: inline;"> Electronic liquid crystal (ELC) phases are spontaneous symmetry breaking states believed to arise from strong electron correlation in quantum materials such as cuprates and iron pnictides. Here, we report a direct observation of a smectic phase in a weakly correlated Dirac nodal line (DNL) semimetal GdSbxTe2-x. Incommensurate smectic charge modulation and intense local unidirectional nanostructure… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2402.18893v3-abstract-full').style.display = 'inline'; document.getElementById('2402.18893v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2402.18893v3-abstract-full" style="display: none;"> Electronic liquid crystal (ELC) phases are spontaneous symmetry breaking states believed to arise from strong electron correlation in quantum materials such as cuprates and iron pnictides. Here, we report a direct observation of a smectic phase in a weakly correlated Dirac nodal line (DNL) semimetal GdSbxTe2-x. Incommensurate smectic charge modulation and intense local unidirectional nanostructure are visualized by using spectroscopic imaging - scanning tunneling microscopy. As topological materials with symmetry protected Dirac or Weyl fermions are mostly weakly correlated, the discovery of such an ELC phase are anomalous and raise questions on the origin of their emergence. Specifically, we demonstrate how chemical substitution generates these symmetry breaking phases before the system undergoes a charge density wave (CDW) - orthorhombic structural transition. Our results highlight the importance of impurities in realizing ELC phases and present a new material platform for exploring the interplay among quenched disorder, topology and electron correlation. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2402.18893v3-abstract-full').style.display = 'none'; document.getElementById('2402.18893v3-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 January, 2025; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 29 February, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2024. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2210.13798">arXiv:2210.13798</a> <span> [<a href="https://arxiv.org/pdf/2210.13798">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/PhysRevResearch.4.L042035">10.1103/PhysRevResearch.4.L042035 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Planar Thermal Hall Effects in Kitaev Spin Liquid Candidate Na2Co2TeO6 </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Takeda%2C+H">Hikaru Takeda</a>, <a href="/search/cond-mat?searchtype=author&query=Mai%2C+J">Jiancong Mai</a>, <a href="/search/cond-mat?searchtype=author&query=Akazawa%2C+M">Masatoshi Akazawa</a>, <a href="/search/cond-mat?searchtype=author&query=Tamura%2C+K">Kyo Tamura</a>, <a href="/search/cond-mat?searchtype=author&query=Yan%2C+J">Jian Yan</a>, <a href="/search/cond-mat?searchtype=author&query=Moovendaran%2C+K">Kalimuthu Moovendaran</a>, <a href="/search/cond-mat?searchtype=author&query=Raju%2C+K">Kalaivanan Raju</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Choi%2C+K">Kwang-Yong Choi</a>, <a href="/search/cond-mat?searchtype=author&query=Yamashita%2C+M">Minoru Yamashita</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2210.13798v1-abstract-short" style="display: inline;"> We investigate both the longitudinal thermal conductivity ($魏_{xx}$) and the planar thermal Hall conductivity ($魏_{xy}$) in the Kitaev spin liquid candidate of Co-based honeycomb antiferromagnet Na$_2$Co$_2$TeO$_6$ in a magnetic field ($B$) applied along the $a$ and $a^*$ axes. A finite $魏_{xy}$ is resolved for both field directions in the antiferromagnetic (AFM) phase below the N茅el temperature o… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2210.13798v1-abstract-full').style.display = 'inline'; document.getElementById('2210.13798v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2210.13798v1-abstract-full" style="display: none;"> We investigate both the longitudinal thermal conductivity ($魏_{xx}$) and the planar thermal Hall conductivity ($魏_{xy}$) in the Kitaev spin liquid candidate of Co-based honeycomb antiferromagnet Na$_2$Co$_2$TeO$_6$ in a magnetic field ($B$) applied along the $a$ and $a^*$ axes. A finite $魏_{xy}$ is resolved for both field directions in the antiferromagnetic (AFM) phase below the N茅el temperature of 27 K. The temperature dependence of $魏_{xy}/T$ shows the emergence of topological bosonic excitations. In addition, the field dependence of $魏_{xy}$ shows sign reversals at the critical fields in the AFM phase, suggesting the changes in the Chern number distribution of the topological magnons. Remarkably, a finite $魏_{xy}$ is observed in $B \parallel a^*$ between the first-order transition field in the AFM phase and the saturation field, which is prohibited in a disordered state by the two-fold rotation symmetry around the $a^*$ axis of the honeycomb lattice, showing the presence of a magnetically ordered state that breaks the two-fold rotation symmetry. Our results demonstrate the presence of topological magnons in this compound in the whole field range below the saturation field. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2210.13798v1-abstract-full').style.display = 'none'; document.getElementById('2210.13798v1-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 October, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2022. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">7 pages, 5 figures, and Supplementary Materials. To appear in Phys. Rev. Research</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, L042035 (2022) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2206.00281">arXiv:2206.00281</a> <span> [<a href="https://arxiv.org/pdf/2206.00281">pdf</a>, <a href="https://arxiv.org/ps/2206.00281">ps</a>, <a href="https://arxiv.org/format/2206.00281">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"> Charge density wave and superconductivity in 6R-TaS2 </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Pal%2C+S">Sudip Pal</a>, <a href="/search/cond-mat?searchtype=author&query=Bahera%2C+P">Prakash Bahera</a>, <a href="/search/cond-mat?searchtype=author&query=Sahoo%2C+S+R">S. R. Sahoo</a>, <a href="/search/cond-mat?searchtype=author&query=Srivastava%2C+H">Himanshu Srivastava</a>, <a href="/search/cond-mat?searchtype=author&query=Srivastava%2C+A+K">A. K. Srivastava</a>, <a href="/search/cond-mat?searchtype=author&query=Lalla%2C+N+P">N. P. Lalla</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Banerjee%2C+A">A. Banerjee</a>, <a href="/search/cond-mat?searchtype=author&query=Roy%2C+S+B">S. B. Roy</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="2206.00281v3-abstract-short" style="display: inline;"> The layered transition metal dichalcogenide compounds 1T-TaS2 and 4H-TaS2 are well known for their exotic properties, which include charge density wave, superconductivity, Mott transition, etc., and lately quantum spin liquid. Here, we report the magnetic, transport and transmission electron microscopy study of the charge density wave and superconductivity in 6R-TaS2 which is a relatively less stu… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2206.00281v3-abstract-full').style.display = 'inline'; document.getElementById('2206.00281v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2206.00281v3-abstract-full" style="display: none;"> The layered transition metal dichalcogenide compounds 1T-TaS2 and 4H-TaS2 are well known for their exotic properties, which include charge density wave, superconductivity, Mott transition, etc., and lately quantum spin liquid. Here, we report the magnetic, transport and transmission electron microscopy study of the charge density wave and superconductivity in 6R-TaS2 which is a relatively less studied polymorph of this dichalcogenide TaS2. Our high temperature electron microscopy reveals multiple charge density wave transitions between room temperature and 650K. Magnetization, and the electrical resistivity measurements in the temperature range of 2-400 K reveal that 6R-TaS2 undergoes a charge density wave transition around 305 K and is followed by a transition to a superconducting state around 3.5 K. The low temperature specific heat measurement exhibits anomaly associated with the superconducting transition around 2.4 K. The estimated Ginzburg Landau parameter suggests that this compound lies at the extreme limit of type-II superconductivity. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2206.00281v3-abstract-full').style.display = 'none'; document.getElementById('2206.00281v3-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 August, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 1 June, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2022. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2110.07266">arXiv:2110.07266</a> <span> [<a href="https://arxiv.org/pdf/2110.07266">pdf</a>, <a href="https://arxiv.org/format/2110.07266">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1002/advs.202105720">10.1002/advs.202105720 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Lorentz-boost-driven magneto-optics in a Dirac nodal-line semimetal </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Wyzula%2C+J">J. Wyzula</a>, <a href="/search/cond-mat?searchtype=author&query=Lu%2C+X">X. Lu</a>, <a href="/search/cond-mat?searchtype=author&query=Santos-Cottin%2C+D">D. Santos-Cottin</a>, <a href="/search/cond-mat?searchtype=author&query=Mukherjee%2C+D+K">D. K. Mukherjee</a>, <a href="/search/cond-mat?searchtype=author&query=Mohelsky%2C+I">I. Mohelsky</a>, <a href="/search/cond-mat?searchtype=author&query=Mardele%2C+F+L">F. Le Mardele</a>, <a href="/search/cond-mat?searchtype=author&query=Novak%2C+J">J. Novak</a>, <a href="/search/cond-mat?searchtype=author&query=Novak%2C+M">M. Novak</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Krupko%2C+Y">Y. Krupko</a>, <a href="/search/cond-mat?searchtype=author&query=Piot%2C+B+A">B. A. Piot</a>, <a href="/search/cond-mat?searchtype=author&query=Lee%2C+W+-">W. -L. Lee</a>, <a href="/search/cond-mat?searchtype=author&query=Akrap%2C+A">A. Akrap</a>, <a href="/search/cond-mat?searchtype=author&query=Potemski%2C+M">M. Potemski</a>, <a href="/search/cond-mat?searchtype=author&query=Goerbig%2C+M+O">M. O. Goerbig</a>, <a href="/search/cond-mat?searchtype=author&query=Orlita%2C+M">M. Orlita</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="2110.07266v3-abstract-short" style="display: inline;"> Optical response of crystalline solids is to a large extent driven by excitations that promote electrons among individual bands. This allows one to apply optical and magneto-optical methods to determine experimentally the energy band gap - a fundamental property crucial to our understanding of any solid - with a great precision. Here we show that such conventional methods, applied with great succe… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2110.07266v3-abstract-full').style.display = 'inline'; document.getElementById('2110.07266v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2110.07266v3-abstract-full" style="display: none;"> Optical response of crystalline solids is to a large extent driven by excitations that promote electrons among individual bands. This allows one to apply optical and magneto-optical methods to determine experimentally the energy band gap - a fundamental property crucial to our understanding of any solid - with a great precision. Here we show that such conventional methods, applied with great success to many materials in the past, do not work in topological Dirac semimetals with a dispersive nodal line. There, the optically deduced band gap depends on how the magnetic field is oriented with respect to the crystal axes. Such highly unusual behaviour is explained in terms of band-gap renormalization driven by Lorentz boosts. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2110.07266v3-abstract-full').style.display = 'none'; document.getElementById('2110.07266v3-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 July, 2022; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 14 October, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 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">9 pages, 3 figures + supplementary materials</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Advanced Science 2105720 (2022) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2108.06012">arXiv:2108.06012</a> <span> [<a href="https://arxiv.org/pdf/2108.06012">pdf</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.104.075145">10.1103/PhysRevB.104.075145 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Robust topological state against magnetic impurities observed in superconductor PbTaSe2 </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Multer%2C+D">Daniel Multer</a>, <a href="/search/cond-mat?searchtype=author&query=Yin%2C+J">Jia-Xin Yin</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+S+S">Songtian S. Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Zheng%2C+H">Hao Zheng</a>, <a href="/search/cond-mat?searchtype=author&query=Chang%2C+T">Tay-Rong Chang</a>, <a href="/search/cond-mat?searchtype=author&query=Bian%2C+G">Guang Bian</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Hasan%2C+M+Z">M. Zahid Hasan</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="2108.06012v1-abstract-short" style="display: inline;"> Magnetic impurities deposited on topological superconductor candidate PbTaSe2 can introduce a non-splitting zero-energy state inside the superconducting gap, which has been proposed as a field-free platform for topological zero modes. However, it is still unclear how robust the topological state in PbTaSe2 is against magnetic impurities, which is related to the topological nature of the zero-energ… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2108.06012v1-abstract-full').style.display = 'inline'; document.getElementById('2108.06012v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2108.06012v1-abstract-full" style="display: none;"> Magnetic impurities deposited on topological superconductor candidate PbTaSe2 can introduce a non-splitting zero-energy state inside the superconducting gap, which has been proposed as a field-free platform for topological zero modes. However, it is still unclear how robust the topological state in PbTaSe2 is against magnetic impurities, which is related to the topological nature of the zero-energy state as well as its potential for quantum computation. In this work, we use scanning tunneling microscopy (STM) to study the topological surface state in the normal state of PbTaSe2 under the perturbation of magnetic impurities. We visualize the quasi-particle interference (QPI) arising from the topological surface state. We then deposit Fe impurities on the surface to form atomic Fe adatoms. We find that each Fe adatom sits at a unique interstitial position on the surface and features a local state at high energies, both of which are consistent with our first-principles calculation that further reveals its large magnetic moment. Our systematic Fe deposition and subsequent measurements show that the arc-like QPI pattern at the Fermi energy is robust with up to 3% Fe coverage where the atomic nature of Fe adatoms still holds. Our results provide evidence that the topological surface state at the Fermi energy in PbTaSe2 is robust against dilute magnetic impurities. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2108.06012v1-abstract-full').style.display = 'none'; document.getElementById('2108.06012v1-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 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">Journal ref:</span> Phys. Rev. B 104, 075145 (2021) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2106.11600">arXiv:2106.11600</a> <span> [<a href="https://arxiv.org/pdf/2106.11600">pdf</a>, <a href="https://arxiv.org/ps/2106.11600">ps</a>, <a href="https://arxiv.org/format/2106.11600">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.127.076402">10.1103/PhysRevLett.127.076402 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Pressure-induced excitations in the out-of-plane optical response of the nodal-line semimetal ZrSiS </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Ebad-Allah%2C+J">J. Ebad-Allah</a>, <a href="/search/cond-mat?searchtype=author&query=Rojewski%2C+S">S. Rojewski</a>, <a href="/search/cond-mat?searchtype=author&query=V%C3%B6st%2C+M">M. V枚st</a>, <a href="/search/cond-mat?searchtype=author&query=Eickerling%2C+G">G. Eickerling</a>, <a href="/search/cond-mat?searchtype=author&query=Scherer%2C+W">W. Scherer</a>, <a href="/search/cond-mat?searchtype=author&query=Uykur%2C+E">E. Uykur</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Varrassi%2C+L">L. Varrassi</a>, <a href="/search/cond-mat?searchtype=author&query=Franchini%2C+C">C. Franchini</a>, <a href="/search/cond-mat?searchtype=author&query=Ahn%2C+K">K. Ahn</a>, <a href="/search/cond-mat?searchtype=author&query=Kune%C5%A1%2C+J">J. Kune拧</a>, <a href="/search/cond-mat?searchtype=author&query=Kuntscher%2C+C+A">C. A. Kuntscher</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="2106.11600v1-abstract-short" style="display: inline;"> The anisotropic optical response of the layered, nodal-line semimetal ZrSiS at ambient and high pressure is investigated by frequency-dependent reflectivity measurements for the polarization along and perpendicular to the layers. The highly anisotropic optical conductivity is in very good agreement with results from density functional theory calculations and confirms the anisotropic character of Z… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2106.11600v1-abstract-full').style.display = 'inline'; document.getElementById('2106.11600v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2106.11600v1-abstract-full" style="display: none;"> The anisotropic optical response of the layered, nodal-line semimetal ZrSiS at ambient and high pressure is investigated by frequency-dependent reflectivity measurements for the polarization along and perpendicular to the layers. The highly anisotropic optical conductivity is in very good agreement with results from density functional theory calculations and confirms the anisotropic character of ZrSiS. Whereas the in-plane optical conductivity shows only modest pressure-induced changes, we found strong effects on the out-of-plane optical conductivity spectrum of ZrSiS, with the appearance of two prominent excitations. These pronounced pressure-induced effects can neither be attributed to a structural phase transition according to our single-crystal x-ray diffraction measurements, nor can they be explained by electronic correlation and electron-hole pairing effects, as revealed by theoretical calculations. Our findings are discussed in the context of the recently proposed excitonic insulator phase in ZrSiS. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2106.11600v1-abstract-full').style.display = 'none'; document.getElementById('2106.11600v1-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 June, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 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, 3 figures, accepted for publication in Phys. Rev. Lett</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2101.05166">arXiv:2101.05166</a> <span> [<a href="https://arxiv.org/pdf/2101.05166">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevMaterials.6.044201">10.1103/PhysRevMaterials.6.044201 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Observation of a Smoothly Tunable Dirac Point in $Ge(Bi_{x}Sb_{1-x})_{2}Te_{4}$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Howard%2C+S">Sean Howard</a>, <a href="/search/cond-mat?searchtype=author&query=Raghavan%2C+A">Arjun Raghavan</a>, <a href="/search/cond-mat?searchtype=author&query=Iaia%2C+D">Davide Iaia</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+C">Caizhi Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Fl%C3%B6totto%2C+D">David Fl枚totto</a>, <a href="/search/cond-mat?searchtype=author&query=Wong%2C+M">Man-Hong Wong</a>, <a href="/search/cond-mat?searchtype=author&query=Mo%2C+S">Sung-Kwan Mo</a>, <a href="/search/cond-mat?searchtype=author&query=Singh%2C+B">Bahadur Singh</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Lin%2C+H">Hsin Lin</a>, <a href="/search/cond-mat?searchtype=author&query=Chiang%2C+T">Tai-Chang Chiang</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="2101.05166v3-abstract-short" style="display: inline;"> State-of-the-art topological devices require the use topological surface states to drive electronic transport. In this study, we examine a tunable topological system, $Ge(Bi_{x}Sb_{1-x})_{2}Te_{4}$, for a range of 'x' values from 0 to 1, using a combination of Fourier Transform Scanning Tunneling Spectroscopy (FT-STS) and Angle-Resolved Photoemission Spectroscopy (ARPES). Our results show that the… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2101.05166v3-abstract-full').style.display = 'inline'; document.getElementById('2101.05166v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2101.05166v3-abstract-full" style="display: none;"> State-of-the-art topological devices require the use topological surface states to drive electronic transport. In this study, we examine a tunable topological system, $Ge(Bi_{x}Sb_{1-x})_{2}Te_{4}$, for a range of 'x' values from 0 to 1, using a combination of Fourier Transform Scanning Tunneling Spectroscopy (FT-STS) and Angle-Resolved Photoemission Spectroscopy (ARPES). Our results show that the Dirac point shifts linearly with 'x', crossing the Fermi energy near x = 0.7. This novel observation of a smoothly tunable, isolated Dirac point crossing through the topological transport regime and having strong linear dependence with substitution can be critical for future topological spintronics applications. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2101.05166v3-abstract-full').style.display = 'none'; document.getElementById('2101.05166v3-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 October, 2021; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 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">Comments:</span> <span class="has-text-grey-dark mathjax">18 Pages, 9 Figures, including Appendix</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Mater. 6, 044201 (2022) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2011.06358">arXiv:2011.06358</a> <span> [<a href="https://arxiv.org/pdf/2011.06358">pdf</a>, <a href="https://arxiv.org/format/2011.06358">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.L241108">10.1103/PhysRevB.103.L241108 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Hot carrier-assisted switching of the electron-phonon interaction in 1$T$-VSe$_2$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Majchrzak%2C+P">Paulina Majchrzak</a>, <a href="/search/cond-mat?searchtype=author&query=Pakdel%2C+S">Sahar Pakdel</a>, <a href="/search/cond-mat?searchtype=author&query=Biswas%2C+D">Deepnarayan Biswas</a>, <a href="/search/cond-mat?searchtype=author&query=Jones%2C+A+J+H">Alfred J. H. Jones</a>, <a href="/search/cond-mat?searchtype=author&query=Volckaert%2C+K">Klara Volckaert</a>, <a href="/search/cond-mat?searchtype=author&query=Markovi%C4%87%2C+I">Igor Markovi膰</a>, <a href="/search/cond-mat?searchtype=author&query=Andreatta%2C+F">Federico Andreatta</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Jozwiak%2C+C">Chris Jozwiak</a>, <a href="/search/cond-mat?searchtype=author&query=Rotenberg%2C+E">Eli Rotenberg</a>, <a href="/search/cond-mat?searchtype=author&query=Bostwick%2C+A">Aaron Bostwick</a>, <a href="/search/cond-mat?searchtype=author&query=Sanders%2C+C+E">Charlotte E. Sanders</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+Y">Yu Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Karras%2C+G">Gabriel Karras</a>, <a href="/search/cond-mat?searchtype=author&query=Chapman%2C+R+T">Richard T. Chapman</a>, <a href="/search/cond-mat?searchtype=author&query=Wyatt%2C+A">Adam Wyatt</a>, <a href="/search/cond-mat?searchtype=author&query=Springate%2C+E">Emma Springate</a>, <a href="/search/cond-mat?searchtype=author&query=Miwa%2C+J+A">Jill A. Miwa</a>, <a href="/search/cond-mat?searchtype=author&query=Hofmann%2C+P">Philip Hofmann</a>, <a href="/search/cond-mat?searchtype=author&query=King%2C+P+D+C">Phil D. C. King</a>, <a href="/search/cond-mat?searchtype=author&query=Lanata%2C+N">Nicola Lanata</a>, <a href="/search/cond-mat?searchtype=author&query=Chang%2C+Y+J">Young Jun Chang</a>, <a href="/search/cond-mat?searchtype=author&query=Ulstrup%2C+S">S酶ren Ulstrup</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="2011.06358v1-abstract-short" style="display: inline;"> We apply an intense infrared laser pulse in order to perturb the electronic and vibrational states in the three-dimensional charge density wave material 1$T$-VSe$_2$. Ultrafast snapshots of the light-induced hot carrier dynamics and non-equilibrium quasiparticle spectral function are collected using time- and angle-resolved photoemission spectroscopy. The hot carrier temperature and time-dependent… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2011.06358v1-abstract-full').style.display = 'inline'; document.getElementById('2011.06358v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2011.06358v1-abstract-full" style="display: none;"> We apply an intense infrared laser pulse in order to perturb the electronic and vibrational states in the three-dimensional charge density wave material 1$T$-VSe$_2$. Ultrafast snapshots of the light-induced hot carrier dynamics and non-equilibrium quasiparticle spectral function are collected using time- and angle-resolved photoemission spectroscopy. The hot carrier temperature and time-dependent electronic self-energy are extracted from the time-dependent spectral function, revealing that incoherent electron-phonon interactions heat the lattice above the charge density wave critical temperature on a timescale of $(200 \pm 40)$~fs. Density functional perturbation theory calculations establish that the presence of hot carriers alters the overall phonon dispersion and quenches efficient low-energy acoustic phonon scattering channels, which results in a new quasi-equilibrium state that is experimentally observed. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2011.06358v1-abstract-full').style.display = 'none'; document.getElementById('2011.06358v1-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 November, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 2020. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">24 pages including supplemental material, 4 figures in the main text and 4 figures in the supplemental material</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, 241108 (2021) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2007.11364">arXiv:2007.11364</a> <span> [<a href="https://arxiv.org/pdf/2007.11364">pdf</a>, <a href="https://arxiv.org/format/2007.11364">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.102.024517">10.1103/PhysRevB.102.024517 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Fully gapped superconductivity without sign reversal in the topological superconductor PbTaSe$_2$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Sun%2C+Y">Yue Sun</a>, <a href="/search/cond-mat?searchtype=author&query=Kittaka%2C+S">Shunichiro Kittaka</a>, <a href="/search/cond-mat?searchtype=author&query=Sakakibara%2C+T">Toshiro Sakakibara</a>, <a href="/search/cond-mat?searchtype=author&query=Machida%2C+K">Kazushige Machida</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+X">Xiaofeng Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Zhou%2C+N">Nan Zhou</a>, <a href="/search/cond-mat?searchtype=author&query=Xing%2C+X">Xiangzhuo Xing</a>, <a href="/search/cond-mat?searchtype=author&query=Shi%2C+Z">Zhixiang Shi</a>, <a href="/search/cond-mat?searchtype=author&query=Pyon%2C+S">Sunseng Pyon</a>, <a href="/search/cond-mat?searchtype=author&query=Tamegai%2C+T">Tsuyoshi Tamegai</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2007.11364v1-abstract-short" style="display: inline;"> We investigate the superconducting gap function of topological superconductor PbTaSe$_2$. Temperature, magnetic field, and three-dimensional (3D) field-angle dependences of the specific heat prove that the superconductivity of PbTaSe$_2$ is fully-gapped, with two isotropic $s$-wave gaps. The pair-breaking effect is probed by systematically increasing non-magnetic disorders through H$^+$-irradiatio… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2007.11364v1-abstract-full').style.display = 'inline'; document.getElementById('2007.11364v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2007.11364v1-abstract-full" style="display: none;"> We investigate the superconducting gap function of topological superconductor PbTaSe$_2$. Temperature, magnetic field, and three-dimensional (3D) field-angle dependences of the specific heat prove that the superconductivity of PbTaSe$_2$ is fully-gapped, with two isotropic $s$-wave gaps. The pair-breaking effect is probed by systematically increasing non-magnetic disorders through H$^+$-irradiations. The superconducting transition temperature, $T_{\rm{c}}$, is found to be robust against disorders, which suggests that the pairing should be sign-preserved rather than sign-reversed. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2007.11364v1-abstract-full').style.display = 'none'; document.getElementById('2007.11364v1-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, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2020. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">9 pages, 7 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 102, 024517 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2006.12775">arXiv:2006.12775</a> <span> [<a href="https://arxiv.org/pdf/2006.12775">pdf</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> <p class="title is-5 mathjax"> Wohlleben Effect and Emergent Pi junctions in superconducting Boron doped Diamond thin films </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Govindaraj%2C+L">L. Govindaraj</a>, <a href="/search/cond-mat?searchtype=author&query=Arumugam%2C+S">S. Arumugam</a>, <a href="/search/cond-mat?searchtype=author&query=Thiyagarajan%2C+R">R. Thiyagarajan</a>, <a href="/search/cond-mat?searchtype=author&query=Kumar%2C+D">Dinesh Kumar</a>, <a href="/search/cond-mat?searchtype=author&query=Kannan%2C+M">M. Kannan</a>, <a href="/search/cond-mat?searchtype=author&query=Das%2C+D">Dhrubha Das</a>, <a href="/search/cond-mat?searchtype=author&query=Suraj%2C+T+S">T. S. Suraj</a>, <a href="/search/cond-mat?searchtype=author&query=Sankaranarayanan%2C+V">V. Sankaranarayanan</a>, <a href="/search/cond-mat?searchtype=author&query=Sethupathi%2C+K">K. Sethupathi</a>, <a href="/search/cond-mat?searchtype=author&query=Baskaran%2C+G">G. Baskaran</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Rao%2C+M+S+R">M. S. Ramachandra Rao</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="2006.12775v1-abstract-short" style="display: inline;"> Diamond is an excellent band insulator. However, boron (B) doping is known to induce superconductivity. We present two interesting effects in superconducting B doped diamond (BDD) thin films: i) Wohlleben effect (paramagnetic Meissner effect, PME) and ii) a low field spin glass like susceptibility anomaly. We have performed electrical and magnetic measurements (under pressure in one sample) at dop… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2006.12775v1-abstract-full').style.display = 'inline'; document.getElementById('2006.12775v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2006.12775v1-abstract-full" style="display: none;"> Diamond is an excellent band insulator. However, boron (B) doping is known to induce superconductivity. We present two interesting effects in superconducting B doped diamond (BDD) thin films: i) Wohlleben effect (paramagnetic Meissner effect, PME) and ii) a low field spin glass like susceptibility anomaly. We have performed electrical and magnetic measurements (under pressure in one sample) at dopings (1.4 , 2.6 and 3.6) X 1021 cm-3, in a temperature range 2 - 10 K. PME, a low field anomaly in inhomogeneous superconductors could arise from flux trapping, flux compression, or for non-trivial reason such as emergent Josephson Pi junctions. Joint occurrence of PME and spin glass type anomalies points to possible emergence of Pi junctions. BDD is a disordered s-wave superconductor; and Pi junctions could be produced by spin flip scattering of spin half moments when present at weak superconducting regions (Bulaevski et al. 1978). A frustrated network of 0 and Pi junctions will result (Kusmartsev et al. 1992) in a distribution of spontaneous equilibrium supercurrents, a phase glass state. Anderson localized spin half spinons embedded in a metallic fluid (two fluid model of Bhatt et al.) could create Pi junction by spin flip scattering. Our findings are consistent with presence of Pi junctions, invoked to explain their (Bhattacharyya et al.) observation of certain resistance anomaly in BDD. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2006.12775v1-abstract-full').style.display = 'none'; document.getElementById('2006.12775v1-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">Comments:</span> <span class="has-text-grey-dark mathjax">21 Pages, 7 Figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2006.09164">arXiv:2006.09164</a> <span> [<a href="https://arxiv.org/pdf/2006.09164">pdf</a>, <a href="https://arxiv.org/ps/2006.09164">ps</a>, <a href="https://arxiv.org/format/2006.09164">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"> Anisotropic transport and quantum oscillations in the quasi-one-dimensional TaNiTe5: Evidence for the nontrivial band topology </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Xu%2C+C+Q">C. Q. Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Liu%2C+Y">Y. Liu</a>, <a href="/search/cond-mat?searchtype=author&query=Cai%2C+P+G">P. G. Cai</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+B">B. Li</a>, <a href="/search/cond-mat?searchtype=author&query=Jiao%2C+W+H">W. H. Jiao</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+Y+L">Y. L. Li</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+J+Y">J. Y. Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Zhou%2C+W">W. Zhou</a>, <a href="/search/cond-mat?searchtype=author&query=Qian%2C+B">B. Qian</a>, <a href="/search/cond-mat?searchtype=author&query=Jiang%2C+X+F">X. F. Jiang</a>, <a href="/search/cond-mat?searchtype=author&query=Shi%2C+Z+X">Z. X. Shi</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+J+L">J. L. Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Yang%2C+F">F. Yang</a>, <a href="/search/cond-mat?searchtype=author&query=Zhu%2C+Z">Zengwei Zhu</a>, <a href="/search/cond-mat?searchtype=author&query=Biswas%2C+P+K">P. K. Biswas</a>, <a href="/search/cond-mat?searchtype=author&query=Qian%2C+D">Dong Qian</a>, <a href="/search/cond-mat?searchtype=author&query=Ke%2C+X">X. Ke</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+X">Xiaofeng Xu</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="2006.09164v1-abstract-short" style="display: inline;"> The past decade has witnessed the burgeoning discovery of a variety of topological states of matter with distinct nontrivial band topologies. Thus far, most of materials studied possess two-dimensional or three-dimensional electronic structures, with only a few exceptions that host quasi-one-dimensional (quasi-1D) topological electronic properties. Here we present the clear-cut evidence for Dirac… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2006.09164v1-abstract-full').style.display = 'inline'; document.getElementById('2006.09164v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2006.09164v1-abstract-full" style="display: none;"> The past decade has witnessed the burgeoning discovery of a variety of topological states of matter with distinct nontrivial band topologies. Thus far, most of materials studied possess two-dimensional or three-dimensional electronic structures, with only a few exceptions that host quasi-one-dimensional (quasi-1D) topological electronic properties. Here we present the clear-cut evidence for Dirac fermions in the quasi-1D telluride TaNiTe5. We show that its transport behaviors are highly anisotropic and we observe nontrivial Berry phases via the quantum oscillation measurements. The nontrivial band topology is further corroborated by first-principles calculations. Our results may help to guide the future quest for topological states in this new family of quasi-1D ternary chalcogenides. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2006.09164v1-abstract-full').style.display = 'none'; document.getElementById('2006.09164v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 16 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">5 figures, 1 table</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> J. Phys. Chem. Lett. 11, 7782 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2004.10962">arXiv:2004.10962</a> <span> [<a href="https://arxiv.org/pdf/2004.10962">pdf</a>, <a href="https://arxiv.org/ps/2004.10962">ps</a>, <a href="https://arxiv.org/format/2004.10962">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Applied Physics">physics.app-ph</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1021/acsami.0c01025">10.1021/acsami.0c01025 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Ultralow Schottky Barriers in hBN-Encapsulated Monolayer WSe$_2$ Tunnel Field-Effect Transistors </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Pande%2C+G">Gaurav Pande</a>, <a href="/search/cond-mat?searchtype=author&query=Siao%2C+J">Jyun-Yan Siao</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+W">Wei-Liang Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Lee%2C+C">Chien-Ju Lee</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Chang%2C+Y">Yu-Ming Chang</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+C">Chii-Dong Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Chang%2C+W">Wen-Hao Chang</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">Fang-Cheng Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Lin%2C+M">Minn-Tsong Lin</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2004.10962v1-abstract-short" style="display: inline;"> To explore the potential of field-effect transistors (FETs) based on monolayers of the two-dimensional semiconducting channel(SC) for spintronics, the two most important issues are to ensure the formation of variable low resistive tunnel ferromagnetic contacts(FC), and to preserve intrinsic properties of the SC during fabrication. Large Schottky barriers lead to the formation of high resistive con… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2004.10962v1-abstract-full').style.display = 'inline'; document.getElementById('2004.10962v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2004.10962v1-abstract-full" style="display: none;"> To explore the potential of field-effect transistors (FETs) based on monolayers of the two-dimensional semiconducting channel(SC) for spintronics, the two most important issues are to ensure the formation of variable low resistive tunnel ferromagnetic contacts(FC), and to preserve intrinsic properties of the SC during fabrication. Large Schottky barriers lead to the formation of high resistive contacts and methods adopted to control the barriers often alter the intrinsic properties of the SC. This work aims at addressing both issues in fully encapsulated monolayer WSe$_2$ FETs by using bi-layer h-BN as a tunnel barrier at the FC/SC interface. We investigate the electrical transport in monolayer WSe$_2$ FETs with current-in-plane geometry that yields hole mobilities $\sim$ 38.3 $cm^{2}V^{-1}s^{-1}$ at 240 K and On/Off ratios of the order of 10$^7$, limited by the contact regions. We have achieved ultralow effective Schottky barrier ($\sim$ 5.34 meV) with encapsulated tunneling device as opposed to a non-encapsulated device in which the barrier heights are considerably higher. These observations provide an insight into the electrical behavior of the FC/h-BN/SC/h-BN heterostructures and such control over the barrier heights opens up the possibilities for WSe$_2$-based spintronic devices. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2004.10962v1-abstract-full').style.display = 'none'; document.getElementById('2004.10962v1-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 April, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2020. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Applied Materials and Interfaces \{copyright} American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/abs/10.1021/acsami.0c01025</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> ACS Appl. Mater. Interfaces 12, 16, 18667-18673 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2004.10879">arXiv:2004.10879</a> <span> [<a href="https://arxiv.org/pdf/2004.10879">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Disordered Systems and Neural Networks">cond-mat.dis-nn</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.102.121301">10.1103/PhysRevB.102.121301 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Electron-Electron Interactions in 2D Semiconductor InSe </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Kumar%2C+A+S">Arvind Shankar Kumar</a>, <a href="/search/cond-mat?searchtype=author&query=Premasiri%2C+K">Kasun Premasiri</a>, <a href="/search/cond-mat?searchtype=author&query=Gao%2C+M">Min Gao</a>, <a href="/search/cond-mat?searchtype=author&query=Kumar%2C+U+R">U. Rajesh Kumar</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">Fang-Cheng Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Gao%2C+X+P+A">Xuan P. A. Gao</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2004.10879v1-abstract-short" style="display: inline;"> Electron-electron interactions (EEIs) in 2D van der Waals structures is one of the topics with high current interest in physics. We report the observation of a negative parabolic magnetoresistance (MR) in multilayer 2D semiconductor InSe beyond the low-field weak localization/antilocalization regime, and provide evidence for the EEI origin of this MR behavior. Further, we analyze this negative par… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2004.10879v1-abstract-full').style.display = 'inline'; document.getElementById('2004.10879v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2004.10879v1-abstract-full" style="display: none;"> Electron-electron interactions (EEIs) in 2D van der Waals structures is one of the topics with high current interest in physics. We report the observation of a negative parabolic magnetoresistance (MR) in multilayer 2D semiconductor InSe beyond the low-field weak localization/antilocalization regime, and provide evidence for the EEI origin of this MR behavior. Further, we analyze this negative parabolic MR and other observed quantum transport signatures of EEIs (temperature dependent conductance and Hall coefficient) within the framework of Fermi liquid theory and extract the gate voltage tunable Fermi liquid parameter $F_0^蟽$ which quantifies the electron spin-exchange interaction strength. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2004.10879v1-abstract-full').style.display = 'none'; document.getElementById('2004.10879v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 22 April, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2020. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 102, 121301 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2002.00135">arXiv:2002.00135</a> <span> [<a href="https://arxiv.org/pdf/2002.00135">pdf</a>, <a href="https://arxiv.org/format/2002.00135">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/PhysRevB.107.214405">10.1103/PhysRevB.107.214405 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Random magnetic anisotropy driven transitions in layered perovskite LaSrCoO$_4$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Ahad%2C+A">Abdul Ahad</a>, <a href="/search/cond-mat?searchtype=author&query=Gautam%2C+K">K. Gautam</a>, <a href="/search/cond-mat?searchtype=author&query=Majid%2C+S+S">S. S. Majid</a>, <a href="/search/cond-mat?searchtype=author&query=Dey%2C+K">K. Dey</a>, <a href="/search/cond-mat?searchtype=author&query=Tripathy%2C+A">A. Tripathy</a>, <a href="/search/cond-mat?searchtype=author&query=Rahman%2C+F">F. Rahman</a>, <a href="/search/cond-mat?searchtype=author&query=Choudhary%2C+R+J">R. J. Choudhary</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Sinha%2C+A+K">A. K. Sinha</a>, <a href="/search/cond-mat?searchtype=author&query=Kaul%2C+S+N">S. N. Kaul</a>, <a href="/search/cond-mat?searchtype=author&query=Shukla%2C+D+K">D. K. Shukla</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="2002.00135v3-abstract-short" style="display: inline;"> Attempts to unravel the nature of magnetic ordering in LaSrCoO$_4$ (Co$^{3+}$), a compound intermediate between antiferromagnetic (AFM) La$_2$CoO$_4$ (Co$^{2+}$) and ferromagnetic (FM) Sr$_2$CoO$_4$ (Co$^{4+}$), have met with a limited success so far. In this report, the results of a thorough investigation of dc magnetization and ac susceptibility (ACS) in single-phase LaSrCoO$_4$ provide clinchin… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2002.00135v3-abstract-full').style.display = 'inline'; document.getElementById('2002.00135v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2002.00135v3-abstract-full" style="display: none;"> Attempts to unravel the nature of magnetic ordering in LaSrCoO$_4$ (Co$^{3+}$), a compound intermediate between antiferromagnetic (AFM) La$_2$CoO$_4$ (Co$^{2+}$) and ferromagnetic (FM) Sr$_2$CoO$_4$ (Co$^{4+}$), have met with a limited success so far. In this report, the results of a thorough investigation of dc magnetization and ac susceptibility (ACS) in single-phase LaSrCoO$_4$ provide clinching evidence for a thermodynamic paramagnetic (PM) - ferromagnetic (FM) phase transition at T$_{c}$ = 220.5 K, followed at lower temperature (T$_{g}$ = 7.7 K) by a transition to the cluster spin glass (CSG) state. Analysis of the low-field Arrott plot isotherms, in the critical region near T$_{c}$, in terms of the Aharony-Pytte scaling equation of state clearly establishes that the PM-FM transition is basically driven by random magnetic anisotropy (RMA). For temperatures below $\approx$ 30 K, large enough RMA destroys long-range FM order by breaking up the infinite FM network into FM clusters of finite size and leads to the formation of a CSG state at temperatures T $\lesssim$ 8 K by promoting freezing of finite FM clusters in random orientations. Increasing strength of the single-ion magnetocrystalline anisotropy (and hence RMA) with decreasing temperature is taken to reflect an increase in the number of low-spin (LS) Co$^{3+}$ ions at the expense of that of high-spin (HS) Co$^{3+}$ ions. At intermediate temperatures (30 K $\lesssim T \lesssim$ 180 K), spin dynamics has contributions from the infinite FM network (fast relaxation governed by a single anisotropy energy barrier) and finite FM clusters (extremely slow stretched exponential relaxation due to hierarchical energy barriers). <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2002.00135v3-abstract-full').style.display = 'none'; document.getElementById('2002.00135v3-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 16 May, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 31 January, 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">23 pages, 9 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 107, 214405 (2023) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1912.11513">arXiv:1912.11513</a> <span> [<a href="https://arxiv.org/pdf/1912.11513">pdf</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> </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.101.100507">10.1103/PhysRevB.101.100507 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Field-free platform for topological zero-energy mode in superconductors LiFeAs and PbTaSe$_2$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+S+S">Songtian S. Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Yin%2C+J">Jia-Xin Yin</a>, <a href="/search/cond-mat?searchtype=author&query=Dai%2C+G">Guangyang Dai</a>, <a href="/search/cond-mat?searchtype=author&query=Zhao%2C+L">Lingxiao Zhao</a>, <a href="/search/cond-mat?searchtype=author&query=Chang%2C+T">Tay-Rong Chang</a>, <a href="/search/cond-mat?searchtype=author&query=Shumiya%2C+N">Nana Shumiya</a>, <a href="/search/cond-mat?searchtype=author&query=Jiang%2C+K">Kun Jiang</a>, <a href="/search/cond-mat?searchtype=author&query=Zheng%2C+H">Hao Zheng</a>, <a href="/search/cond-mat?searchtype=author&query=Bian%2C+G">Guang Bian</a>, <a href="/search/cond-mat?searchtype=author&query=Multer%2C+D">Daniel Multer</a>, <a href="/search/cond-mat?searchtype=author&query=Litskevich%2C+M">Maksim Litskevich</a>, <a href="/search/cond-mat?searchtype=author&query=Chang%2C+G">Guoqing Chang</a>, <a href="/search/cond-mat?searchtype=author&query=Belopolski%2C+I">Ilya Belopolski</a>, <a href="/search/cond-mat?searchtype=author&query=Cochran%2C+T+A">Tyler A. Cochran</a>, <a href="/search/cond-mat?searchtype=author&query=Wu%2C+X">Xianxin Wu</a>, <a href="/search/cond-mat?searchtype=author&query=Wu%2C+D">Desheng Wu</a>, <a href="/search/cond-mat?searchtype=author&query=Luo%2C+J">Jianlin Luo</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+G">Genfu Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Lin%2C+H">Hsin Lin</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">Fang-Cheng Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%2C+X">Xiancheng Wang</a>, <a href="/search/cond-mat?searchtype=author&query=Jin%2C+C">Changqing Jin</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%2C+Z">Ziqiang Wang</a>, <a href="/search/cond-mat?searchtype=author&query=Hasan%2C+M+Z">M. Zahid Hasan</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1912.11513v1-abstract-short" style="display: inline;"> Superconducting materials exhibiting topological properties are emerging as an exciting platform to realize fundamentally new excitations from topological quantum states of matter. In this work, we explore the possibility of a field-free platform for generating Majorana zero energy excitations by depositing magnetic Fe impurities on the surface of candidate topological superconductors, LiFeAs and… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1912.11513v1-abstract-full').style.display = 'inline'; document.getElementById('1912.11513v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1912.11513v1-abstract-full" style="display: none;"> Superconducting materials exhibiting topological properties are emerging as an exciting platform to realize fundamentally new excitations from topological quantum states of matter. In this work, we explore the possibility of a field-free platform for generating Majorana zero energy excitations by depositing magnetic Fe impurities on the surface of candidate topological superconductors, LiFeAs and PbTaSe$_2$. We use scanning tunneling microscopy to probe localized states induced at the Fe adatoms on the atomic scale and at sub-Kelvin temperatures. We find that each Fe adatom generates a striking zero-energy bound state inside the superconducting gap, which do not split in magnetic fields up to 8T, underlining a nontrivial topological origin. Our findings point to magnetic Fe adatoms evaporated on bulk superconductors with topological surface states as a new platform for exploring Majorana zero modes and quantum information science under field-free conditions. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1912.11513v1-abstract-full').style.display = 'none'; document.getElementById('1912.11513v1-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 December, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">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, 100507 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1912.07002">arXiv:1912.07002</a> <span> [<a href="https://arxiv.org/pdf/1912.07002">pdf</a>, <a href="https://arxiv.org/format/1912.07002">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/10.1088/1367-2630/ac2b53">10.1088/1367-2630/ac2b53 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Dirac Nodal Line and Rashba Splitting Surface States in Nonsymmorphic ZrGeTe </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Yen%2C+Y">Yun Yen</a>, <a href="/search/cond-mat?searchtype=author&query=Chiu%2C+C">Cheng-Li Chiu</a>, <a href="/search/cond-mat?searchtype=author&query=Lin%2C+P">Ping-Hui Lin</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">Fangcheng Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Chuang%2C+T">Tien-Ming Chuang</a>, <a href="/search/cond-mat?searchtype=author&query=Guo%2C+G">Guang-Yu Guo</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1912.07002v1-abstract-short" style="display: inline;"> Dirac semimetals (DSMs) are three dimensional analogue to graphene with symmety enforced bulk Dirac nodes. Among various DSMs, ZrSiS has been attracting more interests recently, due to its three dimensional Dirac nodal line protected by the nonsymmorphic symmetry. It actually belongs to a large family of isostructural compounds with unique quantum phenomenon. Here we present a comprehensive study… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1912.07002v1-abstract-full').style.display = 'inline'; document.getElementById('1912.07002v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1912.07002v1-abstract-full" style="display: none;"> Dirac semimetals (DSMs) are three dimensional analogue to graphene with symmety enforced bulk Dirac nodes. Among various DSMs, ZrSiS has been attracting more interests recently, due to its three dimensional Dirac nodal line protected by the nonsymmorphic symmetry. It actually belongs to a large family of isostructural compounds with unique quantum phenomenon. Here we present a comprehensive study of the first principle calculation, angle-resolved photoemission spectroscopy (ARPES) measurements, and scanning tunneling microscope (STM) experiments on ZrGeTe, a member of the ZrSiS family with stronger spin-orbit coupling (SOC). Our band structure calculation shows the existence of floating gapless surface states at $\bar{X}$ with Rashba splitted helical spin texture, which are confirmed by our ARPES measurements. We also perform quasiparticle scattering interference (QPI) imaging and find several q-vectors, with two Umklapp scattering vectors not observed in other family compounds. All the q-vectors can be identified with joint density of states (JDOS) simulation. Our results demonstrate the interesting electronic structure of ZrGeTe and might benefit the potential application by utilizing its exotic quantum states in the future. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1912.07002v1-abstract-full').style.display = 'none'; document.getElementById('1912.07002v1-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 December, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">12 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/1911.09327">arXiv:1911.09327</a> <span> [<a href="https://arxiv.org/pdf/1911.09327">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <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"> Oxidized-monolayer Tunneling Barrier for Strong Fermi-level Depinning in Layered InSe Transistors </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Chen%2C+Y">Yi-Hsun Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Cheng%2C+C">Chih-Yi Cheng</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+S">Shao-Yu Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Rodriguez%2C+J+S+D">Jan Sebastian Dominic Rodriguez</a>, <a href="/search/cond-mat?searchtype=author&query=Liao%2C+H">Han-Ting Liao</a>, <a href="/search/cond-mat?searchtype=author&query=Watanabe%2C+K">Kenji Watanabe</a>, <a href="/search/cond-mat?searchtype=author&query=Taniguchi%2C+T">Takashi Taniguchi</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+C">Chun-Wei Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">Fang-Cheng Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Chiu%2C+H">Hsiang-Chih Chiu</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%2C+W">Wei-Hua Wang</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="1911.09327v1-abstract-short" style="display: inline;"> In 2D-semiconductor-based field-effect transistors and optoelectronic devices, metal-semiconductor junctions are one of the crucial factors determining device performance. The Fermi-level (FL) pinning effect, which commonly caused by interfacial gap states, severely limits the tunability of junction characteristics, including barrier height and contact resistance. A tunneling contact scheme has be… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1911.09327v1-abstract-full').style.display = 'inline'; document.getElementById('1911.09327v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1911.09327v1-abstract-full" style="display: none;"> In 2D-semiconductor-based field-effect transistors and optoelectronic devices, metal-semiconductor junctions are one of the crucial factors determining device performance. The Fermi-level (FL) pinning effect, which commonly caused by interfacial gap states, severely limits the tunability of junction characteristics, including barrier height and contact resistance. A tunneling contact scheme has been suggested to address the FL pinning issue in metal-2D-semiconductor junctions, whereas the experimental realization is still elusive. Here, we show that an oxidized-monolayer-enabled tunneling barrier can realize a pronounced FL depinning in indium selenide (InSe) transistors, exhibiting a large pinning factor of 0.5 and a highly modulated Schottky barrier height. The FL depinning can be attributed to the suppression of metal- and disorder-induced gap states as a result of the high-quality tunneling contacts. Structural characterizations indicate uniform and atomically thin surface oxidation layer inherent from nature of van der Waals materials and atomically sharp oxide-2D-semiconductor interfaces. Moreover, by effectively lowering the Schottky barrier height, we achieve an electron mobility of 2160 cm$^2$/Vs and a contact barrier of 65 meV in two-terminal InSe transistors. The realization of strong FL depinning in high-mobility InSe transistors with the oxidized monolayer presents a viable strategy to exploit layered semiconductors in contact engineering for advanced electronics and optoelectronics. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1911.09327v1-abstract-full').style.display = 'none'; document.getElementById('1911.09327v1-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, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 2019. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1908.00371">arXiv:1908.00371</a> <span> [<a href="https://arxiv.org/pdf/1908.00371">pdf</a>, <a href="https://arxiv.org/format/1908.00371">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/PhysRevB.101.224430">10.1103/PhysRevB.101.224430 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Magnetic and orbital correlations in multiferroic CaMn$_7$O$_{12}$ probed by x-ray resonant elastic scattering </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Gautam%2C+K">K. Gautam</a>, <a href="/search/cond-mat?searchtype=author&query=Majid%2C+S+S">S. S. Majid</a>, <a href="/search/cond-mat?searchtype=author&query=Francoual%2C+S">S. Francoual</a>, <a href="/search/cond-mat?searchtype=author&query=Ahad%2C+A">A. Ahad</a>, <a href="/search/cond-mat?searchtype=author&query=Dey%2C+K">K. Dey</a>, <a href="/search/cond-mat?searchtype=author&query=Rahn%2C+M+C">M. C. Rahn</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F+C">F. C. Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Shukla%2C+D+K">D. K. Shukla</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="1908.00371v2-abstract-short" style="display: inline;"> The quadruple perovskite CaMn$_7$O$_{12}$ is a topical multiferroic, in which the hierarchy of electronic correlations driving structural distortions, modulated magnetism, and orbital order is not well known and may vary with temperature. x-ray resonant elastic scattering (XRES) provides a momentum-resolved tool to study these phenomena, even in very small single crystals, with valuable informatio… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1908.00371v2-abstract-full').style.display = 'inline'; document.getElementById('1908.00371v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1908.00371v2-abstract-full" style="display: none;"> The quadruple perovskite CaMn$_7$O$_{12}$ is a topical multiferroic, in which the hierarchy of electronic correlations driving structural distortions, modulated magnetism, and orbital order is not well known and may vary with temperature. x-ray resonant elastic scattering (XRES) provides a momentum-resolved tool to study these phenomena, even in very small single crystals, with valuable information encoded in its polarization- and energy-dependence. We present an application of this technique to CaMn$_7$O$_{12}$. By polarization analysis, it is possible to distinguish superstructure reflections associated with magnetic order and orbital order. Given the high momentum resolution, we resolve a previously unknown splitting of an orbital order superstructure peak, associated with a distinct \textit{locked-in} phase at low temperatures. A second set of orbital order superstructure peaks can then be interpreted as a second-harmonic orbital signal. Surprisingly, the intensities of the first- and second-harmonic orbital signal show disparate temperature and polarization dependence. This orbital re-ordering may be driven by an exchange mechanism, that becomes dominant over the Jahn-Teller instability at low temperature. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1908.00371v2-abstract-full').style.display = 'none'; document.getElementById('1908.00371v2-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 June, 2020; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 1 August, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 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 and 1 supplementary with 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, 224430 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1905.11177">arXiv:1905.11177</a> <span> [<a href="https://arxiv.org/pdf/1905.11177">pdf</a>, <a href="https://arxiv.org/ps/1905.11177">ps</a>, <a href="https://arxiv.org/format/1905.11177">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/10.1016/j.scib.2020.04.039">10.1016/j.scib.2020.04.039 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Evidence for nematic superconductivity of topological surface states in PbTaSe2 </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Le%2C+T">Tian Le</a>, <a href="/search/cond-mat?searchtype=author&query=Sun%2C+Y">Yue Sun</a>, <a href="/search/cond-mat?searchtype=author&query=Jin%2C+H">Hui-Ke Jin</a>, <a href="/search/cond-mat?searchtype=author&query=Che%2C+L">Liqiang Che</a>, <a href="/search/cond-mat?searchtype=author&query=Yin%2C+L">Lichang Yin</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+J">Jie Li</a>, <a href="/search/cond-mat?searchtype=author&query=Pang%2C+G+M">G. M. Pang</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+C+Q">C. Q. Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Zhao%2C+L+X">L. X. Zhao</a>, <a href="/search/cond-mat?searchtype=author&query=Kittaka%2C+S">S. Kittaka</a>, <a href="/search/cond-mat?searchtype=author&query=Sakakibara%2C+T">T. Sakakibara</a>, <a href="/search/cond-mat?searchtype=author&query=Machida%2C+K">K. Machida</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Yuan%2C+H+Q">H. Q. Yuan</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+G+F">G. F. Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+X">Xiaofeng Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+S">Shiyan Li</a>, <a href="/search/cond-mat?searchtype=author&query=Zhou%2C+Y">Yi Zhou</a>, <a href="/search/cond-mat?searchtype=author&query=Lu%2C+X">Xin Lu</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="1905.11177v1-abstract-short" style="display: inline;"> Spontaneous symmetry breaking has been a paradigm to describe the phase transitions in condensed matter physics. In addition to the continuous electromagnetic gauge symmetry, an unconventional superconductor can break discrete symmetries simultaneously, such as time reversal and lattice rotational symmetry. In this work we report a characteristic in-plane 2-fold behaviour of the resistive upper cr… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1905.11177v1-abstract-full').style.display = 'inline'; document.getElementById('1905.11177v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1905.11177v1-abstract-full" style="display: none;"> Spontaneous symmetry breaking has been a paradigm to describe the phase transitions in condensed matter physics. In addition to the continuous electromagnetic gauge symmetry, an unconventional superconductor can break discrete symmetries simultaneously, such as time reversal and lattice rotational symmetry. In this work we report a characteristic in-plane 2-fold behaviour of the resistive upper critical field and point-contact spectra on the superconducting semimetal PbTaSe2 with topological nodal-rings, despite its hexagonal lattice symmetry (or D_3h in bulk while C_3v on surface, to be precise). However, we do not observe any lattice rotational symmetry breaking signal from field-angle-dependent specific heat. It is worth noting that such surface-only electronic nematicity is in sharp contrast to the observation in the topological superconductor candidate, CuxBi2Se3, where the nematicity occurs in various bulk measurements. In combination with theory, superconducting nematicity is likely to emerge from the topological surface states of PbTaSe2, rather than the proximity effect. The issue of time reversal symmetry breaking is also addressed. Thus, our results on PbTaSe2 shed new light on possible routes to realize nematic superconductivity with nontrivial topology. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1905.11177v1-abstract-full').style.display = 'none'; document.getElementById('1905.11177v1-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 May, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 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">3 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Science Bulletin 65, 1349 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1810.03726">arXiv:1810.03726</a> <span> [<a href="https://arxiv.org/pdf/1810.03726">pdf</a>, <a href="https://arxiv.org/format/1810.03726">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevMaterials.2.120302">10.1103/PhysRevMaterials.2.120302 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> 3D Dirac semimetal Cd3As2: A review of material properties </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Crassee%2C+I">I. Crassee</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Lee%2C+W+-">W. -L. Lee</a>, <a href="/search/cond-mat?searchtype=author&query=Akrap%2C+A">A. Akrap</a>, <a href="/search/cond-mat?searchtype=author&query=Orlita%2C+M">M. Orlita</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1810.03726v2-abstract-short" style="display: inline;"> Cadmium arsenide (Cd3As2) - a time-honored and widely explored material in solid-state physics - has recently attracted considerable attention. This was triggered by a theoretical prediction concerning the presence of 3D symmetry-protected massless Dirac electrons, which could turn Cd3As2 into a 3D analogue of graphene. Subsequent extended experimental studies have provided us with compelling expe… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1810.03726v2-abstract-full').style.display = 'inline'; document.getElementById('1810.03726v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1810.03726v2-abstract-full" style="display: none;"> Cadmium arsenide (Cd3As2) - a time-honored and widely explored material in solid-state physics - has recently attracted considerable attention. This was triggered by a theoretical prediction concerning the presence of 3D symmetry-protected massless Dirac electrons, which could turn Cd3As2 into a 3D analogue of graphene. Subsequent extended experimental studies have provided us with compelling experimental evidence of conical bands in this system, and revealed a number of interesting properties and phenomena. At the same time, some of the material properties remain the subject of vast discussions despite recent intensive experimental and theoretical efforts, which may hinder the progress in understanding and applications of this appealing material. In this review, we focus on the basic material parameters and properties of Cd3As2, in particular those which are directly related to the conical features in the electronic band structure of this material. The outcome of experimental investigations, performed on Cd3As2 using various spectroscopic and transport techniques within the past sixty years, is compared with theoretical studies. These theoretical works gave us not only simplified effective models, but more recently, also the electronic band structure calculated numerically using ab initio methods. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1810.03726v2-abstract-full').style.display = 'none'; document.getElementById('1810.03726v2-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 January, 2019; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 8 October, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">16 pages, 16 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Materials 2, 120302 (2018) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1809.10689">arXiv:1809.10689</a> <span> [<a href="https://arxiv.org/pdf/1809.10689">pdf</a>, <a href="https://arxiv.org/format/1809.10689">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="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevB.99.155116">10.1103/PhysRevB.99.155116 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Topological nature of step edge states on the surface of topological crystalline insulator Pb$_{0.7}$Sn$_{0.3}$Se </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Iaia%2C+D">Davide Iaia</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%2C+C">Chang-Yan Wang</a>, <a href="/search/cond-mat?searchtype=author&query=Maximenko%2C+Y">Yulia Maximenko</a>, <a href="/search/cond-mat?searchtype=author&query=Walkup%2C+D">Daniel Walkup</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">Fangcheng Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Lu%2C+Y">Yuan-Ming Lu</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="1809.10689v3-abstract-short" style="display: inline;"> In addition to novel surface states, topological insulators can also exhibit robust gapless states at crystalline defects. Step edges constitute a class of common defects on the surface of crystals. In this work we establish the topological nature of one-dimensional (1D) bound states localized at step edges of the [001] surface of a topological crystalline insulator (TCI) Pb$_{0.7}$Sn$_{0.3}$Se, b… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1809.10689v3-abstract-full').style.display = 'inline'; document.getElementById('1809.10689v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1809.10689v3-abstract-full" style="display: none;"> In addition to novel surface states, topological insulators can also exhibit robust gapless states at crystalline defects. Step edges constitute a class of common defects on the surface of crystals. In this work we establish the topological nature of one-dimensional (1D) bound states localized at step edges of the [001] surface of a topological crystalline insulator (TCI) Pb$_{0.7}$Sn$_{0.3}$Se, both theoretically and experimentally. We show that the topological stability of the step edge states arises from an emergent particle-hole symmetry of the surface low-energy physics, and demonstrate the experimental signatures of the particle-hole symmetry breaking. We also reveal the effects of an external magnetic field on the 1D bound states. Our work suggests the possibility of similar topological step edge modes in other topological materials with a rocks-salt structure. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1809.10689v3-abstract-full').style.display = 'none'; document.getElementById('1809.10689v3-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 25 January, 2019; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 27 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">Comments:</span> <span class="has-text-grey-dark mathjax">8+6 pages, 6 figures, references and acknowledgements updated</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 99, 155116 (2019) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1809.03181">arXiv:1809.03181</a> <span> [<a href="https://arxiv.org/pdf/1809.03181">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> </div> <p class="title is-5 mathjax"> High-performance InSe Transistors with Ohmic Contact Enabled by Nonrectifying-barrier-type Indium Electrodes </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Huang%2C+Y">Yu-Ting Huang</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+Y">Yi-Hsun Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Ho%2C+Y">Yi-Ju Ho</a>, <a href="/search/cond-mat?searchtype=author&query=Huang%2C+S">Shih-Wei Huang</a>, <a href="/search/cond-mat?searchtype=author&query=Chang%2C+Y">Yih-Ren Chang</a>, <a href="/search/cond-mat?searchtype=author&query=Watanabe%2C+K">Kenji Watanabe</a>, <a href="/search/cond-mat?searchtype=author&query=Taniguchi%2C+T">Takashi Taniguchi</a>, <a href="/search/cond-mat?searchtype=author&query=Chiu%2C+H">Hsiang-Chih Chiu</a>, <a href="/search/cond-mat?searchtype=author&query=Liang%2C+C">Chi-Te Liang</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">Fang-Cheng Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+C">Chun-Wei Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%2C+W">Wei-Hua Wang</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="1809.03181v1-abstract-short" style="display: inline;"> The electrical contact to two-dimensional (2D)-semiconductor materials are decisive to the electronic performance of 2D-semiconductor field-effect devices (FEDs). The presence of a Schottky barrier often leads to a large contact resistance, which seriously limits the channel conductance and carrier mobility measured in a two-terminal geometry. In contrast, ohmic contact is desirable and can be ach… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1809.03181v1-abstract-full').style.display = 'inline'; document.getElementById('1809.03181v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1809.03181v1-abstract-full" style="display: none;"> The electrical contact to two-dimensional (2D)-semiconductor materials are decisive to the electronic performance of 2D-semiconductor field-effect devices (FEDs). The presence of a Schottky barrier often leads to a large contact resistance, which seriously limits the channel conductance and carrier mobility measured in a two-terminal geometry. In contrast, ohmic contact is desirable and can be achieved by the presence of a nonrectifying or tunneling barrier. Here, we demonstrate that an nonrectifying barrier can be realized by contacting indium (In), a low work function metal, with layered InSe because of a favorable band alignment at the In-InSe interface. The nonrectifying barrier is manifested by ohmic contact behavior at T=2 K and a low barrier height, 桅$_B$=50 meV. This ohmic contact enables demonstration of an ON-current as large as 410 渭A/渭m, which is among the highest values achieved in FEDs based on layered semiconductors. A high electron mobility of 3,700 and 1,000 cm$^2$/Vs is achieved with the two-terminal In-InSe FEDs at T=2 K and room temperature, respectively, which can be attributed to enhanced quality of both conduction channel and the contacts. The improvement in the contact quality is further proven by an X-ray photoelectron spectroscopy study, which suggests that a reduction effect occurs at the In-InSe interface. The demonstration of high-performance In-InSe FEDs indicates a viable interface engineering method for next-generation, 2D-semiconductor-based electronics. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1809.03181v1-abstract-full').style.display = 'none'; document.getElementById('1809.03181v1-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 September, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2018. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1808.08367">arXiv:1808.08367</a> <span> [<a href="https://arxiv.org/pdf/1808.08367">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/10.1088/1367-2630/aae5c8">10.1088/1367-2630/aae5c8 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Surface Termination Dependent Quasiparticle Scattering Interference and Magneto-transport Study on ZrSiS </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Su%2C+C">Chih-Chuan Su</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+C">Chi-Sheng Li</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%2C+T">Tzu-Cheng Wang</a>, <a href="/search/cond-mat?searchtype=author&query=Guan%2C+S">Syu-You Guan</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">Fangcheng Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Chang%2C+C">Chia-Seng Chang</a>, <a href="/search/cond-mat?searchtype=author&query=Lee%2C+W">Wei-Li Lee</a>, <a href="/search/cond-mat?searchtype=author&query=Guo%2C+G">Guang-Yu Guo</a>, <a href="/search/cond-mat?searchtype=author&query=Chuang%2C+T">Tien-Ming Chuang</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1808.08367v2-abstract-short" style="display: inline;"> Dirac nodal line semimetals represent a new state of quantum matters in which the electronic bands touch to form a closed loop with linear dispersion. Here, we report a combined study on ZrSiS by density functional theory calculation, scanning tunneling microscope (STM) and magneto-transport measurements. Our STM measurements reveal the spectroscopic signatures of a diamond-shaped Dirac bulk band… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.08367v2-abstract-full').style.display = 'inline'; document.getElementById('1808.08367v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1808.08367v2-abstract-full" style="display: none;"> Dirac nodal line semimetals represent a new state of quantum matters in which the electronic bands touch to form a closed loop with linear dispersion. Here, we report a combined study on ZrSiS by density functional theory calculation, scanning tunneling microscope (STM) and magneto-transport measurements. Our STM measurements reveal the spectroscopic signatures of a diamond-shaped Dirac bulk band and a surface band on two types of cleaved surfaces as well as a spin polarized surface band at ${\bar螕}$ at E~0.6eV on S-surface, consistent with our band calculation. Furthermore, we find the surface termination does not affect the surface spectral weight from the Dirac bulk bands but greatly affect the surface bands due to the change in the surface orbital composition. From our magneto-transport measurements, the primary Shubnikov de-Haas frequency is identified to stem from the hole-type quasi-two-dimensional Fermi surface between 螕 and X. The extracted non-orbital magnetoresistance (MR) contribution D($胃$, H) yields a nearly H-linear dependence, which is attributed to the intrinsic MR in ZrSiS. Our results demonstrate the unique Dirac line nodes phase and the dominating role of Zr-d orbital on the electronic structure in ZrSiS and the related compounds. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.08367v2-abstract-full').style.display = 'none'; document.getElementById('1808.08367v2-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 October, 2018; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 25 August, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> New Journal of Physics 20, 103025 (2018) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1808.07610">arXiv:1808.07610</a> <span> [<a href="https://arxiv.org/pdf/1808.07610">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"> Topological Type-II Dirac Fermions Approaching the Fermi Level in a Transition Metal Dichalcogenide NiTe2 </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Xu%2C+C">Chunqiang Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+B">Bin Li</a>, <a href="/search/cond-mat?searchtype=author&query=Jiao%2C+W">Wenhe Jiao</a>, <a href="/search/cond-mat?searchtype=author&query=Zhou%2C+W">Wei Zhou</a>, <a href="/search/cond-mat?searchtype=author&query=Qian%2C+B">Bin Qian</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Zhigadlo%2C+N+D">Nikolai D. Zhigadlo</a>, <a href="/search/cond-mat?searchtype=author&query=Qi%2C+Y">Yanpeng Qi</a>, <a href="/search/cond-mat?searchtype=author&query=Qian%2C+D">Dong Qian</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">Fang-Cheng Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+X">Xiaofeng Xu</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1808.07610v1-abstract-short" style="display: inline;"> Type-II Dirac/Weyl semimetals are characterized by strongly tilted Dirac cones such that the Dirac/Weyl node emerges at the boundary of electron and hole pockets as a new state of quantum matter, distinct from the standard Dirac/Weyl points with a point-like Fermi surface which are referred to as type-I nodes. The type-II Dirac fermions were recently predicted by theory and have since been confirm… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.07610v1-abstract-full').style.display = 'inline'; document.getElementById('1808.07610v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1808.07610v1-abstract-full" style="display: none;"> Type-II Dirac/Weyl semimetals are characterized by strongly tilted Dirac cones such that the Dirac/Weyl node emerges at the boundary of electron and hole pockets as a new state of quantum matter, distinct from the standard Dirac/Weyl points with a point-like Fermi surface which are referred to as type-I nodes. The type-II Dirac fermions were recently predicted by theory and have since been confirmed in experiments in the PtSe2-class of transition metal dichal-cogenides. However, the Dirac nodes observed in PtSe2, PdTe2 and PtTe2 candidates are quite far away from the Fermi level, making the signature of topological fermions obscure as the physical properties are still dominated by the non-Dirac quasiparticles. Here we report the synthesis of a new type-II Dirac semimetal NiTe2 in which a pair of type-II Dirac nodes are located very close to the Fermi level. The quantum oscillations in this material reveal a nontrivial Berry's phase associated with these Dirac fermions. Our first principles calculations further unveil a topological Dirac cone in its surface states. Therefore, NiTe2 may not only represent an improved system to formulate the theoretical understanding of the exotic consequences of type-II Dirac fermions, it also facilitates possible applications based on these topological carriers. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.07610v1-abstract-full').style.display = 'none'; document.getElementById('1808.07610v1-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 August, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">4 figures, 1 table</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Chem. Mater. 30, 4823 (2018) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1808.07609">arXiv:1808.07609</a> <span> [<a href="https://arxiv.org/pdf/1808.07609">pdf</a>, <a href="https://arxiv.org/format/1808.07609">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.96.184503">10.1103/PhysRevB.96.184503 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Correlation between non-Fermi-liquid behavior and superconductivity in (Ca, La)(Fe,Co)As2 iron arsenides: A high-pressure study </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Zhou%2C+W">W. Zhou</a>, <a href="/search/cond-mat?searchtype=author&query=Ke%2C+F">F. Ke</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+X">Xiaofeng Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Xing%2C+X">X. Xing</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+C+Q">C. Q. Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Jiang%2C+X+F">X. F. Jiang</a>, <a href="/search/cond-mat?searchtype=author&query=Qian%2C+B">B. Qian</a>, <a href="/search/cond-mat?searchtype=author&query=Zhou%2C+N">N. Zhou</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+Y">Y. Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+M">M. Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+B">B. Li</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+B">B. Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Shi%2C+Z+X">Z. X. Shi</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1808.07609v1-abstract-short" style="display: inline;"> Non-Fermi-liquid (NFL) phenomena associated with correlation effects have been widely observed in the phase diagrams of unconventional superconducting families. Exploration of the correlation between the normal state NFL, regardless of its microscopic origins, and the superconductivity has been argued as a key to unveiling the mystery of the high-Tc pairing mechanism. Here we systematically invest… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.07609v1-abstract-full').style.display = 'inline'; document.getElementById('1808.07609v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1808.07609v1-abstract-full" style="display: none;"> Non-Fermi-liquid (NFL) phenomena associated with correlation effects have been widely observed in the phase diagrams of unconventional superconducting families. Exploration of the correlation between the normal state NFL, regardless of its microscopic origins, and the superconductivity has been argued as a key to unveiling the mystery of the high-Tc pairing mechanism. Here we systematically investigate the pressure-dependent in-plane resistivity and Hall coefficient (RH ) of a high-quality 112-type Fe-based superconductor Ca1-xLaxFe1-yCoyAs2 (x = 0.2,y = 0.02). With increasing pressure, the normal-state resistivity of the studied sample exhibits a pronounced crossover from non-Fermi-liquid to Fermi-liquid behaviors. Accompanied with this crossover, Tc is gradually suppressed. In parallel, the extremum in the Hall coefficient RH (T ) curve, possibly due to anisotropic scattering induced by spin fluctuations, is also gradually suppressed. The symbiosis of NFL and superconductivity implies that these two phenomena are intimately related. Further study on the pressure-dependent upper critical field reveals that the two-band effects are also gradually weakened with increasing pressure and reduced to the one-band Werthamer-Helfand-Hohenberg limit in the low-Tc regime. Overall, our paper supports the picture that NFL, multigap, and extreme RH (T ) are all of the same magnetic origin, i.e., the spin fluctuations in the 112 iron arsenide superconductors. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.07609v1-abstract-full').style.display = 'none'; document.getElementById('1808.07609v1-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 August, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 96, 184503 (2017) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1808.03034">arXiv:1808.03034</a> <span> [<a href="https://arxiv.org/pdf/1808.03034">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 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.8b01764">10.1021/acs.nanolett.8b01764 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Emergence of a Metal-Insulator Transition and High Temperature Charge Density Waves in VSe2 at the Monolayer Limit </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Duvjir%2C+G">Ganbat Duvjir</a>, <a href="/search/cond-mat?searchtype=author&query=Choi%2C+B+K">Byoung Ki Choi</a>, <a href="/search/cond-mat?searchtype=author&query=Jang%2C+I">Iksu Jang</a>, <a href="/search/cond-mat?searchtype=author&query=Ulstrup%2C+S">S酶ren Ulstrup</a>, <a href="/search/cond-mat?searchtype=author&query=Kang%2C+S">Soonmin Kang</a>, <a href="/search/cond-mat?searchtype=author&query=Ly%2C+T+T">Trinh Thi Ly</a>, <a href="/search/cond-mat?searchtype=author&query=Kim%2C+S">Sanghwa Kim</a>, <a href="/search/cond-mat?searchtype=author&query=Choi%2C+Y+H">Young Hwan Choi</a>, <a href="/search/cond-mat?searchtype=author&query=Jozwiak%2C+C">Chris Jozwiak</a>, <a href="/search/cond-mat?searchtype=author&query=Bostwick%2C+A">Aaron Bostwick</a>, <a href="/search/cond-mat?searchtype=author&query=Rotenberg%2C+E">Eli Rotenberg</a>, <a href="/search/cond-mat?searchtype=author&query=Park%2C+J">Je-Geun Park</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Kim%2C+K">Ki-Seok Kim</a>, <a href="/search/cond-mat?searchtype=author&query=Kim%2C+J">Jungdae Kim</a>, <a href="/search/cond-mat?searchtype=author&query=Chang%2C+Y+J">Young Jun Chang</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1808.03034v1-abstract-short" style="display: inline;"> Emergent phenomena driven by electronic reconstructions in oxide heterostructures have been intensively discussed. However, the role of these phenomena in shaping the electronic properties in van der Waals heterointerfaces has hitherto not been established. By reducing the material thickness and forming a heterointerface, we find two types of charge-ordering transitions in monolayer VSe2 on graphe… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.03034v1-abstract-full').style.display = 'inline'; document.getElementById('1808.03034v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1808.03034v1-abstract-full" style="display: none;"> Emergent phenomena driven by electronic reconstructions in oxide heterostructures have been intensively discussed. However, the role of these phenomena in shaping the electronic properties in van der Waals heterointerfaces has hitherto not been established. By reducing the material thickness and forming a heterointerface, we find two types of charge-ordering transitions in monolayer VSe2 on graphene substrates. Angle-resolved photoemission spectroscopy (ARPES) uncovers that Fermi-surface nesting becomes perfect in ML VSe2. Renormalization group analysis confirms that imperfect nesting in three dimensions universally flows into perfect nesting in two dimensions. As a result, the charge density wave transition temperature is dramatically enhanced to a value of 350 K compared to the 105 K in bulk VSe2. More interestingly, ARPES and scanning tunneling microscopy measurements confirm an unexpected metal-insulator transition at 135 K, driven by lattice distortions. The heterointerface plays an important role in driving this novel metal-insulator transition in the family of monolayered transition metal dichalcogenides. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.03034v1-abstract-full').style.display = 'none'; document.getElementById('1808.03034v1-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 August, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">21 pages, 4 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> published in Nano Letters 2018 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1807.08862">arXiv:1807.08862</a> <span> [<a href="https://arxiv.org/pdf/1807.08862">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> </div> <p class="title is-5 mathjax"> Enhanced Light Emission from the Ridge of Two-dimensional InSe Flakes </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Li%C2%A7%2C+Y">Yang Li搂</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%C2%A7%2C+T">Tianmeng Wang搂</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%C2%A7%2C+H">Han Wang搂</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+Z">Zhipeng Li</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+Y">Yanwen Chen</a>, <a href="/search/cond-mat?searchtype=author&query=West%2C+D">Damien West</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Ulaganathan%2C+R+K">Rajesh K. Ulaganathan</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">Fangcheng Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Wetzel%2C+C">Christian Wetzel</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+C">Cheng-Yan Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+S">Shengbai Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Shi%2C+S">Su-Fei Shi</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="1807.08862v1-abstract-short" style="display: inline;"> InSe, a newly rediscovered two-dimensional (2D) semiconductor, possesses superior electrical and optical properties as a direct bandgap semiconductor with high mobility from bulk to atomically thin layers, drastically different from transition metal dichalcogenides (TMDCs) in which the direct bandgap only exists at the single layer limit. However, absorption in InSe is mostly dominated by an out-o… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1807.08862v1-abstract-full').style.display = 'inline'; document.getElementById('1807.08862v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1807.08862v1-abstract-full" style="display: none;"> InSe, a newly rediscovered two-dimensional (2D) semiconductor, possesses superior electrical and optical properties as a direct bandgap semiconductor with high mobility from bulk to atomically thin layers, drastically different from transition metal dichalcogenides (TMDCs) in which the direct bandgap only exists at the single layer limit. However, absorption in InSe is mostly dominated by an out-of-plane dipole contribution which results in the limited absorption of normally incident light which can only excite the in-plane dipole at resonance. To address this challenge, we have explored a unique geometric ridge state of the 2D flake without compromising the sample quality. We observed the enhanced absorption at the ridge over a broad range of excitation frequencies from photocurrent and photoluminescence (PL) measurements. In addition, we have discovered new PL peaks at low temperature due to defect states on the ridge, which can be as much as ~ 60 times stronger than the intrinsic PL peak of InSe. Interestingly, the PL of the defects is highly tunable through an external electrical field, which can be attributed to the Stark effect of the localized defects. InSe ridges thus provide new avenues for manipulating light-matter interaction and defect-engineering which are vitally crucial for novel optoelectronic devices based on 2D semiconductors. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1807.08862v1-abstract-full').style.display = 'none'; document.getElementById('1807.08862v1-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, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2018. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1806.09665">arXiv:1806.09665</a> <span> [<a href="https://arxiv.org/pdf/1806.09665">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/10.1073/pnas.1718931115">10.1073/pnas.1718931115 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Atomic-Scale Strain Manipulation of a Charge Density Wave </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Gao%2C+S">Shang Gao</a>, <a href="/search/cond-mat?searchtype=author&query=Flicker%2C+F">Felix Flicker</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Zhao%2C+H">He Zhao</a>, <a href="/search/cond-mat?searchtype=author&query=Ren%2C+Z">Zheng Ren</a>, <a href="/search/cond-mat?searchtype=author&query=Rachmilowitz%2C+B">Bryan Rachmilowitz</a>, <a href="/search/cond-mat?searchtype=author&query=Balachandar%2C+S">Sidhika Balachandar</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">Fangcheng Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Burch%2C+K">Kenneth Burch</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%2C+Z">Ziqiang Wang</a>, <a href="/search/cond-mat?searchtype=author&query=van+Wezel%2C+J">Jasper van Wezel</a>, <a href="/search/cond-mat?searchtype=author&query=Zeljkovic%2C+I">Ilija Zeljkovic</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="1806.09665v1-abstract-short" style="display: inline;"> A charge density wave (CDW) is one of the fundamental instabilities of the Fermi surface occurring in a wide range of quantum materials. In dimensions higher than one, where Fermi surface nesting can play only a limited role, the selection of the particular wave vector and geometry of an emerging CDW should in principle be susceptible to controllable manipulation. In this work, we implement a simp… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1806.09665v1-abstract-full').style.display = 'inline'; document.getElementById('1806.09665v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1806.09665v1-abstract-full" style="display: none;"> A charge density wave (CDW) is one of the fundamental instabilities of the Fermi surface occurring in a wide range of quantum materials. In dimensions higher than one, where Fermi surface nesting can play only a limited role, the selection of the particular wave vector and geometry of an emerging CDW should in principle be susceptible to controllable manipulation. In this work, we implement a simple method for straining materials compatible with low-temperature scanning tunneling microscopy/spectroscopy (STM/S), and use it to strain-engineer new CDWs in 2H-NbSe2. Our STM/S measurements combined with theory reveal how small strain-induced changes in the electronic band structure and phonon dispersion lead to dramatic changes in the CDW ordering wave vector and geometry. Our work unveils the microscopic mechanism of a CDW formation in this system, and can serve as a general tool compatible with a range of spectroscopic techniques to engineer novel electronic states in any material where local strain or lattice symmetry breaking plays a role. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1806.09665v1-abstract-full').style.display = 'none'; document.getElementById('1806.09665v1-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 June, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">to appear in PNAS (2018)</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1806.01996">arXiv:1806.01996</a> <span> [<a href="https://arxiv.org/pdf/1806.01996">pdf</a>, <a href="https://arxiv.org/format/1806.01996">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Optics">physics.optics</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1073/pnas.1809631115">10.1073/pnas.1809631115 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Optical Signatures of Dirac Nodal-lines in NbAs$_2$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Shao%2C+Y">Yinming Shao</a>, <a href="/search/cond-mat?searchtype=author&query=Sun%2C+Z">Zhiyuan Sun</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%2C+Y">Ying Wang</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+C">Chenchao Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Breindel%2C+A+J">Alex J. Breindel</a>, <a href="/search/cond-mat?searchtype=author&query=Cao%2C+C">Chao Cao</a>, <a href="/search/cond-mat?searchtype=author&query=Fogler%2C+M+M">M. M. Fogler</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">Fangcheng Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+Z">Zhiqiang Li</a>, <a href="/search/cond-mat?searchtype=author&query=Timusk%2C+T">T. Timusk</a>, <a href="/search/cond-mat?searchtype=author&query=Maple%2C+M+B">M. Brian Maple</a>, <a href="/search/cond-mat?searchtype=author&query=Basov%2C+D+N">D. N. Basov</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="1806.01996v2-abstract-short" style="display: inline;"> Using polarized optical and magneto-optical spectroscopy, we have demonstrated universal aspects of electrodynamics associated with Dirac nodal-lines. We investigated anisotropic electrodynamics of NbAs$_2$ where the spin-orbit interaction triggers energy gaps along the nodal-lines, which manifest as sharp steps in the optical conductivity spectra. We show experimentally and theoretically that shi… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1806.01996v2-abstract-full').style.display = 'inline'; document.getElementById('1806.01996v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1806.01996v2-abstract-full" style="display: none;"> Using polarized optical and magneto-optical spectroscopy, we have demonstrated universal aspects of electrodynamics associated with Dirac nodal-lines. We investigated anisotropic electrodynamics of NbAs$_2$ where the spin-orbit interaction triggers energy gaps along the nodal-lines, which manifest as sharp steps in the optical conductivity spectra. We show experimentally and theoretically that shifted 2D Dirac nodal-lines feature linear scaling $蟽_1 (蠅)\sim蠅$, similar to 3D nodal-points. Massive Dirac nature of the nodal-lines are confirmed by magneto-optical data, which may also be indicative of theoretically predicted surface states. Optical data also offer a natural explanation for the giant magneto-resistance in NbAs$_2$. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1806.01996v2-abstract-full').style.display = 'none'; document.getElementById('1806.01996v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 12 June, 2018; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 5 June, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> PNAS Jan 2019, 116 (4) 1168-1173 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1804.04992">arXiv:1804.04992</a> <span> [<a href="https://arxiv.org/pdf/1804.04992">pdf</a>, <a href="https://arxiv.org/format/1804.04992">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1021/acs.nanolett.8b01462">10.1021/acs.nanolett.8b01462 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Tuning Rashba Spin-Orbit Coupling in Gated Multilayer InSe </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Premasiri%2C+K">Kasun Premasiri</a>, <a href="/search/cond-mat?searchtype=author&query=Radha%2C+S+K">Santosh Kumar Radha</a>, <a href="/search/cond-mat?searchtype=author&query=Sucharitakul%2C+S">Sukrit Sucharitakul</a>, <a href="/search/cond-mat?searchtype=author&query=Kumar%2C+U+R">U. Rajesh Kumar</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">Fang-Cheng Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+Y">Yit-Tsong Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Gao%2C+X+P+A">Xuan P. A. Gao</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1804.04992v2-abstract-short" style="display: inline;"> Manipulating the electron spin with the aid of spin-orbit coupling (SOC) is an indispensable element of spintronics. Electrostatically gating a material with strong SOC results in an effective magnetic field which can in turn be used to govern the electron spin. In this work, we report the existence and electrostatic tunability of Rashba SOC in multilayer InSe. We observed a gate-voltage-tuned cro… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1804.04992v2-abstract-full').style.display = 'inline'; document.getElementById('1804.04992v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1804.04992v2-abstract-full" style="display: none;"> Manipulating the electron spin with the aid of spin-orbit coupling (SOC) is an indispensable element of spintronics. Electrostatically gating a material with strong SOC results in an effective magnetic field which can in turn be used to govern the electron spin. In this work, we report the existence and electrostatic tunability of Rashba SOC in multilayer InSe. We observed a gate-voltage-tuned crossover from weak localization (WL) to weak antilocalization (WAL) effect in quantum transport studies of InSe, which suggests an increasing SOC strength. Quantitative analyses of magneto-transport studies and energy band diagram calculations provide strong evidence for the predominance of Rashba SOC in electrostatically gated InSe. Furthermore, we attribute the tendency of the SOC strength to saturate at high gate voltages to the increased electronic density of states-induced saturation of the electric field experienced by the electrons in the InSe layer. This explanation of nonlinear gate voltage control of Rashba SOC can be generalized to other electrostatically gated semiconductor nanomaterials in which a similar tendency of spin-orbit length saturation was observed (e.g. nanowire field effect transistors), and is thus of broad implications in spintronics. Identifying and controlling the Rashba SOC in InSe may serve pivotally in devising III-VI semiconductor-based spintronic devices in the future. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1804.04992v2-abstract-full').style.display = 'none'; document.getElementById('1804.04992v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 5 July, 2018; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 13 April, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">7 pages, 5 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Nano Lett. 18(7), 4403-4408 (2018) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1804.00845">arXiv:1804.00845</a> <span> [<a href="https://arxiv.org/pdf/1804.00845">pdf</a>, <a href="https://arxiv.org/ps/1804.00845">ps</a>, <a href="https://arxiv.org/format/1804.00845">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"> Dynamic surface electronic reconstruction as symmetry-protected topological orders in topological insulator Bi2Se3 </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Shu%2C+G+J">G. J. Shu</a>, <a href="/search/cond-mat?searchtype=author&query=Liou%2C+S+C">S. C. Liou</a>, <a href="/search/cond-mat?searchtype=author&query=Karna%2C+S+K">S. K. Karna</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Hayashi%2C+M">M. Hayashi</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F+C">F. C. Chou</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1804.00845v1-abstract-short" style="display: inline;"> Layered narrow band gap semiconductor Bi2Se3 is composed of heavy elements with strong spin-orbital coupling (SOC), which has been identified both as a good candidate of thermoelectric material of high thermoelectric figure-of-merit (ZT) and a topological insulator of Z2-type with a gapless surface band in Dirac cone shape. The existence of a conjugated pi-bond system on the surface of each Bi2Se3… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1804.00845v1-abstract-full').style.display = 'inline'; document.getElementById('1804.00845v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1804.00845v1-abstract-full" style="display: none;"> Layered narrow band gap semiconductor Bi2Se3 is composed of heavy elements with strong spin-orbital coupling (SOC), which has been identified both as a good candidate of thermoelectric material of high thermoelectric figure-of-merit (ZT) and a topological insulator of Z2-type with a gapless surface band in Dirac cone shape. The existence of a conjugated pi-bond system on the surface of each Bi2Se3 quintuple layer is proposed based on an extended valence bond model having valence electrons distributed in the hybridized orbitals. Supporting experimental evidences of a 2D conjugated pi-bond system on each quintuple layer of Bi2Se3 are provided by electron energy-loss spectroscopy (EELS) and electron density (ED) mapping through inverse Fourier transform of X-ray diffraction data. Quantum chemistry calculations support the pi-bond existence between partially filled 4pz orbitals of Se via side-to-side orbital overlap positively. The conjugated pi-bond system on the surface of each quintuple Bi2Se3 layer is proposed being similar to that found in graphite (graphene) and responsible for the unique 2D conduction mechanism. The van der Waals (vdW) attractive force between quintuple layers is interpreted being coming from the anti-ferroelectrically ordered effective electric dipoles which are constructed with pi-bond trimer pairs on Se-layers across the vdW gap of minimized Coulomb repulsion. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1804.00845v1-abstract-full').style.display = 'none'; document.getElementById('1804.00845v1-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 April, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">12 pages, 9 figures, to be published in Phys. Rev. Materials</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1803.05469">arXiv:1803.05469</a> <span> [<a href="https://arxiv.org/pdf/1803.05469">pdf</a>, <a href="https://arxiv.org/format/1803.05469">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevB.97.115206">10.1103/PhysRevB.97.115206 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The energy scale of Dirac electrons in Cd3As2 </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Hakl%2C+M">M. Hakl</a>, <a href="/search/cond-mat?searchtype=author&query=Tchoumakov%2C+S">S. Tchoumakov</a>, <a href="/search/cond-mat?searchtype=author&query=Crassee%2C+I">I. Crassee</a>, <a href="/search/cond-mat?searchtype=author&query=Akrap%2C+A">A. Akrap</a>, <a href="/search/cond-mat?searchtype=author&query=Piot%2C+B+A">B. A. Piot</a>, <a href="/search/cond-mat?searchtype=author&query=Faugeras%2C+C">C. Faugeras</a>, <a href="/search/cond-mat?searchtype=author&query=Martinez%2C+G">G. Martinez</a>, <a href="/search/cond-mat?searchtype=author&query=Nateprov%2C+A">A. Nateprov</a>, <a href="/search/cond-mat?searchtype=author&query=Arushanov%2C+E">E. Arushanov</a>, <a href="/search/cond-mat?searchtype=author&query=Teppe%2C+F">F. Teppe</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Lee%2C+W">Wei-li Lee</a>, <a href="/search/cond-mat?searchtype=author&query=Debray%2C+J">J. Debray</a>, <a href="/search/cond-mat?searchtype=author&query=Caha%2C+O">O. Caha</a>, <a href="/search/cond-mat?searchtype=author&query=Novak%2C+J">J. Novak</a>, <a href="/search/cond-mat?searchtype=author&query=Goerbig%2C+M+O">M. O. Goerbig</a>, <a href="/search/cond-mat?searchtype=author&query=Potemski%2C+M">M. Potemski</a>, <a href="/search/cond-mat?searchtype=author&query=Orlita%2C+M">M. Orlita</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="1803.05469v1-abstract-short" style="display: inline;"> Cadmium arsenide (Cd3As2) has recently became conspicuous in solid-state physics due to several reports proposing that it hosts a pair of symmetry-protected 3D Dirac cones. Despite vast investigations, a solid experimental insight into the band structure of this material is still missing. Here we fill one of the existing gaps in our understanding of Cd3As2, and based on our Landau level spectrosco… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1803.05469v1-abstract-full').style.display = 'inline'; document.getElementById('1803.05469v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1803.05469v1-abstract-full" style="display: none;"> Cadmium arsenide (Cd3As2) has recently became conspicuous in solid-state physics due to several reports proposing that it hosts a pair of symmetry-protected 3D Dirac cones. Despite vast investigations, a solid experimental insight into the band structure of this material is still missing. Here we fill one of the existing gaps in our understanding of Cd3As2, and based on our Landau level spectroscopy study, we provide an estimate for the energy scale of 3D Dirac electrons in this system. We find that the appearance of such charge carriers is limited - contrary to a widespread belief in the solid-state community - to a relatively small energy scale (below 40 meV). <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1803.05469v1-abstract-full').style.display = 'none'; document.getElementById('1803.05469v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 14 March, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">to be published in Phys. Rev. B</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 97, 115206 (2018) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1802.05060">arXiv:1802.05060</a> <span> [<a href="https://arxiv.org/pdf/1802.05060">pdf</a>, <a href="https://arxiv.org/format/1802.05060">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.97.195120">10.1103/PhysRevB.97.195120 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Kondo behavior and metamagnetic phase transition in a heavy fermion compound CeBi2 </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Zhou%2C+W">W. Zhou</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+C+Q">C. Q. Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+B">B. Li</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+F+M">F. M. Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Qian%2C+B">B. Qian</a>, <a href="/search/cond-mat?searchtype=author&query=Cao%2C+C">C. Cao</a>, <a href="/search/cond-mat?searchtype=author&query=Dai%2C+J+H">J. H. Dai</a>, <a href="/search/cond-mat?searchtype=author&query=Lu%2C+J">Jianming Lu</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+X">Xiaofeng Xu</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="1802.05060v1-abstract-short" style="display: inline;"> Heavy fermions represent an archetypal example of strongly correlated electron systems which, due to entanglement among different interactions, often exhibit exotic and fascinating physics involving Kondo screening, magnetism and unconventional superconductivity. Here we report a comprehensive study on the transport and thermodynamic properties of a cerium-based heavy fermion compound CeBi$_2$ whi… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1802.05060v1-abstract-full').style.display = 'inline'; document.getElementById('1802.05060v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1802.05060v1-abstract-full" style="display: none;"> Heavy fermions represent an archetypal example of strongly correlated electron systems which, due to entanglement among different interactions, often exhibit exotic and fascinating physics involving Kondo screening, magnetism and unconventional superconductivity. Here we report a comprehensive study on the transport and thermodynamic properties of a cerium-based heavy fermion compound CeBi$_2$ which undergoes an anti-ferromagnetic transition at $T_N$ $\sim$ 3.3 K. Its high temperature paramagnetic state is characterized by an enhanced heat capacity with Sommerfeld coefficient $纬$ over 200 mJ/molK$^2$. The magnetization in the magnetically ordered state features a metamagnetic transition. Remarkably, a large negative magnetoresistance associated with the magnetism was observed in a wide temperature and field-angle range. Collectively, CeBi$_2$ may serve as an intriguing system to study the interplay between $f$ electrons and the itinerant Fermi sea. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1802.05060v1-abstract-full').style.display = 'none'; document.getElementById('1802.05060v1-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 February, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">7 pages, 6 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. B 97, 195120 (2018) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1801.07538">arXiv:1801.07538</a> <span> [<a href="https://arxiv.org/pdf/1801.07538">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> </div> <p class="title is-5 mathjax"> Ultrasensitive Tunability of the Direct Bandgap of Two-dimensional InSe Flakes via Strain Engineering </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Li%C2%A7%2C+Y">Yang Li搂</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%C2%A7%2C+T">Tianmeng Wang搂</a>, <a href="/search/cond-mat?searchtype=author&query=Wu%C2%A7%2C+M">Meng Wu搂</a>, <a href="/search/cond-mat?searchtype=author&query=Cao%2C+T">Ting Cao</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+Y">Yanwen Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Ulaganathan%2C+R+K">Rajesh K. Ulaganathan</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">Fangcheng Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Wetzel%2C+C">Christian Wetzel</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+C">Cheng-Yan Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Louie%2C+S+G">Steven G. Louie</a>, <a href="/search/cond-mat?searchtype=author&query=Shi%2C+S">Sufei Shi</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="1801.07538v1-abstract-short" style="display: inline;"> InSe, a member of the layered materials family, is a superior electronic and optical material which retains a direct bandgap feature from the bulk to atomically thin few-layers and high electronic mobility down to a single layer limit. We, for the first time, exploit strain to drastically modify the bandgap of two-dimensional (2D) InSe nanoflakes. We demonstrated that we could decrease the bandgap… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1801.07538v1-abstract-full').style.display = 'inline'; document.getElementById('1801.07538v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1801.07538v1-abstract-full" style="display: none;"> InSe, a member of the layered materials family, is a superior electronic and optical material which retains a direct bandgap feature from the bulk to atomically thin few-layers and high electronic mobility down to a single layer limit. We, for the first time, exploit strain to drastically modify the bandgap of two-dimensional (2D) InSe nanoflakes. We demonstrated that we could decrease the bandgap of a few-layer InSe flake by 160 meV through applying an in-plane uniaxial tensile strain to 1.06% and increase the bandgap by 79 meV through applying an in-plane uniaxial compressive strain to 0.62%, as evidenced by photoluminescence (PL) spectroscopy. The large reversible bandgap change of ~ 239 meV arises from a large bandgap change rate (bandgap strain coefficient) of few-layer InSe in response to strain, ~ 154 meV/% for uniaxial tensile strain and ~ 140 meV/% for uniaxial compressive strain, representing the most pronounced uniaxial strain-induced bandgap strain coefficient experimentally reported in two-dimensional materials.We developed a theoretical understanding of the strain-induced bandgap change through first-principles DFT and GW calculations. We also confirmed the bandgap change by photoconductivity measurements using excitation light with different photon energies. The highly tunable bandgap of InSe in the infrared regime should enable a wide range of applications, including electro-mechanical, piezoelectric and optoelectronic devices. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1801.07538v1-abstract-full').style.display = 'none'; document.getElementById('1801.07538v1-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 January, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2018. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1801.05162">arXiv:1801.05162</a> <span> [<a href="https://arxiv.org/pdf/1801.05162">pdf</a>, <a href="https://arxiv.org/format/1801.05162">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> </div> <p class="title is-5 mathjax"> Resistivity Anomaly in Weyl Semimetal candidate Molybdenum Telluride </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Suri%2C+D">Dhavala Suri</a>, <a href="/search/cond-mat?searchtype=author&query=Linderalv%2C+C">Christopher Linderalv</a>, <a href="/search/cond-mat?searchtype=author&query=Karpiak%2C+B">Bogdan Karpiak</a>, <a href="/search/cond-mat?searchtype=author&query=Anderson%2C+L">Linnea Anderson</a>, <a href="/search/cond-mat?searchtype=author&query=Singh%2C+S+K">Sandeep Kumar Singh</a>, <a href="/search/cond-mat?searchtype=author&query=Dankert%2C+A">Andre Dankert</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F+C">F. C. Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F+C">F. C. Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Erhart%2C+P">Paul Erhart</a>, <a href="/search/cond-mat?searchtype=author&query=Dash%2C+S+P">Saroj P. Dash</a>, <a href="/search/cond-mat?searchtype=author&query=Patel%2C+R+S">R. S. Patel</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="1801.05162v1-abstract-short" style="display: inline;"> The Weyl semi-metal candidate MoTe$_{2}$ is expected to exhibit a range of exotic electronic transport properties. It exhibits a structural phase transition near room temperature that is evident in the thermal hysteresis in resistivity and thermopower (Seebeck coefficient) as well as large spin-orbit interaction. Here, we also document a resistivity anomaly of up to 13% in the temperature window b… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1801.05162v1-abstract-full').style.display = 'inline'; document.getElementById('1801.05162v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1801.05162v1-abstract-full" style="display: none;"> The Weyl semi-metal candidate MoTe$_{2}$ is expected to exhibit a range of exotic electronic transport properties. It exhibits a structural phase transition near room temperature that is evident in the thermal hysteresis in resistivity and thermopower (Seebeck coefficient) as well as large spin-orbit interaction. Here, we also document a resistivity anomaly of up to 13% in the temperature window between 25 and 50 K, which is found to be strongly anisotropic. Based on the experimental data in conjunction with density functional theory calculations, we conjecture that the anomaly can be related to the presence of defects in the system. These findings open opportunities for further investigations and understanding of the transport behavior in these newly discovered semi-metallic layered systems. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1801.05162v1-abstract-full').style.display = 'none'; document.getElementById('1801.05162v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 16 January, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2018. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1712.08322">arXiv:1712.08322</a> <span> [<a href="https://arxiv.org/pdf/1712.08322">pdf</a>, <a href="https://arxiv.org/format/1712.08322">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> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Strongly Correlated Electrons">cond-mat.str-el</span> </div> </div> <p class="title is-5 mathjax"> Evidence of s-wave superconductivity in the noncentrosymmetric La$_7$Ir$_3$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Li%2C+B">B. Li</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+C+Q">C. Q. Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Zhou%2C+W">W. Zhou</a>, <a href="/search/cond-mat?searchtype=author&query=Jiao%2C+W+H">W. H. Jiao</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+F+M">F. M. Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Hou%2C+H+H">H. H. Hou</a>, <a href="/search/cond-mat?searchtype=author&query=Jiang%2C+X+F">X. F. Jiang</a>, <a href="/search/cond-mat?searchtype=author&query=Qian%2C+B">B. Qian</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+B">B. Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Bangura%2C+A+F">A. F. Bangura</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+X">Xiaofeng Xu</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="1712.08322v1-abstract-short" style="display: inline;"> Superconductivity in noncentrosymmetric compounds has attracted sustained interest in the last decades. Here we present a detailed study on the transport, thermodynamic properties and the band structure of the noncentrosymmetric superconductor La$_7$Ir$_3$ ($T_c$ $\sim$2.3 K) that was recently proposed to break the time-reversal symmetry. It is found that La$_7$Ir$_3$ displays a moderately large e… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1712.08322v1-abstract-full').style.display = 'inline'; document.getElementById('1712.08322v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1712.08322v1-abstract-full" style="display: none;"> Superconductivity in noncentrosymmetric compounds has attracted sustained interest in the last decades. Here we present a detailed study on the transport, thermodynamic properties and the band structure of the noncentrosymmetric superconductor La$_7$Ir$_3$ ($T_c$ $\sim$2.3 K) that was recently proposed to break the time-reversal symmetry. It is found that La$_7$Ir$_3$ displays a moderately large electronic heat capacity (Sommerfeld coefficient $纬_n$ $\sim$ 53.1 mJ/mol $\text{K}^2$) and a significantly enhanced Kadowaki-Woods ratio (KWR $\sim$ 32 $渭惟$ cm mol$^2$ K$^2$ J$^{-2}$) that is greater than the typical value ($\sim$ 10 $渭惟$ cm mol$^2$ K$^2$ J$^{-2}$) for strongly correlated electron systems. The upper critical field $H_{c2}$ was seen to be nicely described by the single-band Werthamer-Helfand-Hohenberg model down to very low temperatures. The hydrostatic pressure effects on the superconductivity were also investigated. The heat capacity below $T_c$ reveals a dominant s-wave gap with the magnitude close to the BCS value. The first-principles calculations yield the electron-phonon coupling constant $位$ = 0.81 and the logarithmically averaged frequency $蠅_{ln}$ = 78.5 K, resulting in a theoretical $T_c$ = 2.5 K, close to the experimental value. Our calculations suggest that the enhanced electronic heat capacity is more likely due to electron-phonon coupling, rather than the electron-electron correlation effects. Collectively, these results place severe constraints on any theory of exotic superconductivity in this system. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1712.08322v1-abstract-full').style.display = 'none'; document.getElementById('1712.08322v1-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 December, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Scientific Reports 8, 651 (2018) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1711.07390">arXiv:1711.07390</a> <span> [<a href="https://arxiv.org/pdf/1711.07390">pdf</a>, <a href="https://arxiv.org/format/1711.07390">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1038/s41467-018-05233-1">10.1038/s41467-018-05233-1 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Distinct multiple fermionic states in a single topological metal </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Hosen%2C+M+M">M. Mofazzel Hosen</a>, <a href="/search/cond-mat?searchtype=author&query=Dimitri%2C+K">Klauss Dimitri</a>, <a href="/search/cond-mat?searchtype=author&query=Nandy%2C+A+K">Ashis K. Nandy</a>, <a href="/search/cond-mat?searchtype=author&query=Aperis%2C+A">Alex Aperis</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Dhakal%2C+G">Gyanendra Dhakal</a>, <a href="/search/cond-mat?searchtype=author&query=Maldonado%2C+P">Pablo Maldonado</a>, <a href="/search/cond-mat?searchtype=author&query=Kabir%2C+F">Firoza Kabir</a>, <a href="/search/cond-mat?searchtype=author&query=Sims%2C+C">Christopher Sims</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">Fangcheng Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Kaczorowski%2C+D">Dariusz Kaczorowski</a>, <a href="/search/cond-mat?searchtype=author&query=Durakiewicz%2C+T">Tomasz Durakiewicz</a>, <a href="/search/cond-mat?searchtype=author&query=Oppeneer%2C+P+M">Peter M. Oppeneer</a>, <a href="/search/cond-mat?searchtype=author&query=Neupane%2C+M">Madhab Neupane</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="1711.07390v1-abstract-short" style="display: inline;"> Among the quantum materials that gained interest recently are the topological Dirac/Weyl semimetals, where conduction and valence bands touch at points in reciprocal (k)-space, and the Dirac nodal-line semimetals, where these bands touch along a line or a loop in k-space. However, the coexistence of multiple fermion phases in one and the same material has not been verified yet. Using angle-resolve… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1711.07390v1-abstract-full').style.display = 'inline'; document.getElementById('1711.07390v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1711.07390v1-abstract-full" style="display: none;"> Among the quantum materials that gained interest recently are the topological Dirac/Weyl semimetals, where conduction and valence bands touch at points in reciprocal (k)-space, and the Dirac nodal-line semimetals, where these bands touch along a line or a loop in k-space. However, the coexistence of multiple fermion phases in one and the same material has not been verified yet. Using angle-resolved photoemission spectroscopy (ARPES) and first-principles electronic structure calculations, we systematically study the metallic topological quantum material, Hf2Te2P. Our investigations discover various properties that are rare and never observed in a single Dirac material. We observe the coexistence of both weak and strong topological surface states in the same material and interestingly, at the same momentum position. An one-dimensional Dirac crossing{the Dirac-node arc-along a high-symmetry direction is revealed by our first-principles calculations and confirmed by our ARPES measurements. This novel state is associated with the surface bands of a weak topological insulator protected by in-plane time-reversal invariance. Ternary compound Hf2Te2P thus emerges as an intriguing platform to study the coexistence and competition of multi-fermionic states in one material. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1711.07390v1-abstract-full').style.display = 'none'; document.getElementById('1711.07390v1-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 November, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">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> Nature Communications 9, 3002 (2018) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1708.00998">arXiv:1708.00998</a> <span> [<a href="https://arxiv.org/pdf/1708.00998">pdf</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/10.1038/s41598-017-07990-3">10.1038/s41598-017-07990-3 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Proximity-effect-induced Superconducting Gap in Topological Surface States - A Point Contact Spectroscopy Study of NbSe2/Bi2Se3 Superconductor-Topological Insulator Heterostructures </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Dai%2C+W">Wenqing Dai</a>, <a href="/search/cond-mat?searchtype=author&query=Richardella%2C+A">Anthony Richardella</a>, <a href="/search/cond-mat?searchtype=author&query=Du%2C+R">Renzhong Du</a>, <a href="/search/cond-mat?searchtype=author&query=Zhao%2C+W">Weiwei Zhao</a>, <a href="/search/cond-mat?searchtype=author&query=Liu%2C+X">Xin Liu</a>, <a href="/search/cond-mat?searchtype=author&query=Liu%2C+C+X">C. X. Liu</a>, <a href="/search/cond-mat?searchtype=author&query=Huang%2C+S">Song-Hsun Huang</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">Fangcheng Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Samarth%2C+N">Nitin Samarth</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+Q">Qi Li</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="1708.00998v1-abstract-short" style="display: inline;"> Proximity-effect-induced superconductivity was studied in epitaxial topological insulator Bi2Se3 thin films grown on superconducting NbSe2 single crystals. A point contact spectroscopy (PCS) method was used at low temperatures down to 40 mK. An induced superconducting gap in Bi2Se3 was observed in the spectra, which decreased with increasing Bi2Se3 layer thickness, consistent with the proximity ef… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1708.00998v1-abstract-full').style.display = 'inline'; document.getElementById('1708.00998v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1708.00998v1-abstract-full" style="display: none;"> Proximity-effect-induced superconductivity was studied in epitaxial topological insulator Bi2Se3 thin films grown on superconducting NbSe2 single crystals. A point contact spectroscopy (PCS) method was used at low temperatures down to 40 mK. An induced superconducting gap in Bi2Se3 was observed in the spectra, which decreased with increasing Bi2Se3 layer thickness, consistent with the proximity effect in the bulk states of Bi2Se3 induced by NbSe2. At very low temperatures, an extra point contact feature which may correspond to a second energy gap appeared in the spectrum. For a 16 quintuple layer Bi2Se3 on NbSe2 sample, the bulk state gap value near the top surface is ~ 159 渭eV, while the second gap value is ~ 120 渭eV at 40 mK. The second gap value decreased with increasing Bi2Se3 layer thickness, but the ratio between the second gap and the bulk state gap remained about the same for different Bi2Se3 thicknesses. It is plausible that this is due to superconductivity in Bi2Se3 topological surface states induced through the bulk states. The two induced gaps in the PCS measurement are consistent with the three-dimensional bulk state and the two-dimensional surface state superconducting gaps observed in the angle-resolved photoemission spectroscopy (ARPES) measurement. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1708.00998v1-abstract-full').style.display = 'none'; document.getElementById('1708.00998v1-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 August, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Scientific Reports 7, 7631 (2017) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1708.00725">arXiv:1708.00725</a> <span> [<a href="https://arxiv.org/pdf/1708.00725">pdf</a>, <a href="https://arxiv.org/ps/1708.00725">ps</a>, <a href="https://arxiv.org/format/1708.00725">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.97.195134">10.1103/PhysRevB.97.195134 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Optical spectroscopy study on pressure-induced phase transitions in the three-dimensional Dirac semimetal Cd$_3$As$_2$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Uykur%2C+E">E. Uykur</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Schmitz%2C+D">D. Schmitz</a>, <a href="/search/cond-mat?searchtype=author&query=Kuntscher%2C+C+A">C. A. Kuntscher</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="1708.00725v1-abstract-short" style="display: inline;"> We report a room-temperature optical reflectivity study performed on [112]-oriented Cd$_3$As$_2$ single crystals over a broad energy range under external pressure up to 10 GPa. The abrupt drop of the band dispersion parameter ($z$-parameter) and the interruption of the gradual redshift of the bandgap at $\sim$4~GPa confirms the structural phase transition from a tetragonal to a monoclinic phase in… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1708.00725v1-abstract-full').style.display = 'inline'; document.getElementById('1708.00725v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1708.00725v1-abstract-full" style="display: none;"> We report a room-temperature optical reflectivity study performed on [112]-oriented Cd$_3$As$_2$ single crystals over a broad energy range under external pressure up to 10 GPa. The abrupt drop of the band dispersion parameter ($z$-parameter) and the interruption of the gradual redshift of the bandgap at $\sim$4~GPa confirms the structural phase transition from a tetragonal to a monoclinic phase in this material. The pressure-induced increase of the overall optical conductivity at low energies and the continuous redshift of the high-energy bands indicate that the system evolves towards a topologically trivial metallic state, although a complete closing of the band gap could not be observed in the studied pressure range. Furthermore, a detailed investigation of the low-pressure regime suggests the possible existence of an intermediate state between 2 and 4~GPa , that might be a precursor of the structural phase transition or due to the lifted degeneracy of the Dirac nodes. Several optical parameters show yet another anomaly at 8~GPa, where low-temperature superconductivity was found in an earlier study. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1708.00725v1-abstract-full').style.display = 'none'; document.getElementById('1708.00725v1-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 August, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">submitted to 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 97, 195134 (2018) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1707.00822">arXiv:1707.00822</a> <span> [<a href="https://arxiv.org/pdf/1707.00822">pdf</a>, <a href="https://arxiv.org/format/1707.00822">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div 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.96.195125">10.1103/PhysRevB.96.195125 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Quasiparticle Interference in ZrSiS - Strongly Band-Selective Scattering Depending on Impurity Lattice Site </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Butler%2C+C+J">Christopher J. Butler</a>, <a href="/search/cond-mat?searchtype=author&query=Wu%2C+Y">Yu-Mi Wu</a>, <a href="/search/cond-mat?searchtype=author&query=Hsing%2C+C">Cheng-Rong Hsing</a>, <a href="/search/cond-mat?searchtype=author&query=Tseng%2C+Y">Yi Tseng</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Wei%2C+C">Ching-Ming Wei</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">Fang-Cheng Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Lin%2C+M">Minn-Tsong Lin</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="1707.00822v2-abstract-short" style="display: inline;"> Scanning tunneling microscopy visualizations of quasiparticle interference (QPI) enable powerful insights into the k-space properties of superconducting, topological, Rashba and other exotic electronic phases, but their reliance on impurities acting as scattering centers is rarely scrutinized. Here we investigate QPI at the vacuum-cleaved (001) surface of the Dirac semimetal ZrSiS. We find that in… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1707.00822v2-abstract-full').style.display = 'inline'; document.getElementById('1707.00822v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1707.00822v2-abstract-full" style="display: none;"> Scanning tunneling microscopy visualizations of quasiparticle interference (QPI) enable powerful insights into the k-space properties of superconducting, topological, Rashba and other exotic electronic phases, but their reliance on impurities acting as scattering centers is rarely scrutinized. Here we investigate QPI at the vacuum-cleaved (001) surface of the Dirac semimetal ZrSiS. We find that interference patterns around impurities located on the Zr and S lattice sites appear very different, and can be ascribed to selective scattering of different sub-sets of the predominantly Zr 4d-derived band structure, namely the m = 0 and m = +/-1 components. We show that the selectivity of scattering channels requires an explanation beyond the different bands' orbital characteristics and their respective charge density distributions over Zr and S lattices sites. Importantly, this result shows that the usual assumption of generic scattering centers allowing observations of quasiparticle interference to shed light indiscriminately and isotropically upon the \textit{q}-space of scattering events does not hold, and that the scope and interpretation of QPI observations can therefore be be strongly contingent on the material defect chemistry. This finding promises to spur new investigations into the quasiparticle scattering process itself, to inform future interpretations of quasiparticle interference observations, and ultimately to aid the understanding and engineering of quantum electronic transport properties. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1707.00822v2-abstract-full').style.display = 'none'; document.getElementById('1707.00822v2-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 November, 2017; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 4 July, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">This version is as accepted for 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 96, 195125 (2017) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1707.00216">arXiv:1707.00216</a> <span> [<a href="https://arxiv.org/pdf/1707.00216">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/PhysRevMaterials.1.064201">10.1103/PhysRevMaterials.1.064201 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Enhanced electron correlations in the new binary stannide PdSn4: a homologue of the Dirac nodal arc semimetal PtSn4 </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Xu%2C+C+Q">C. Q. Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Zhou%2C+W">W. Zhou</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Xing%2C+X+Z">X. Z. Xing</a>, <a href="/search/cond-mat?searchtype=author&query=Shi%2C+Z+X">Z. X. Shi</a>, <a href="/search/cond-mat?searchtype=author&query=Han%2C+Z+D">Z. D. Han</a>, <a href="/search/cond-mat?searchtype=author&query=Qian%2C+B">B. Qian</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%2C+J+H">J. H. Wang</a>, <a href="/search/cond-mat?searchtype=author&query=Zhu%2C+Z">Zengwei Zhu</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+J+L">J. L. Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Bangura%2C+A+F">A. F. Bangura</a>, <a href="/search/cond-mat?searchtype=author&query=Hussey%2C+N+E">N. E. Hussey</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+X">Xiaofeng Xu</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="1707.00216v1-abstract-short" style="display: inline;"> The advent of nodal-line semi-metals, i.e. systems in which the conduction and valence bands cross each other along a closed trajectory (line or loop) inside the Brillouin zone, has opened up a new arena for the exploration of topological condensed matter in which, due to a vanishing density of states near the Fermi level, electron correlation effects may also play an important role. In spite of t… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1707.00216v1-abstract-full').style.display = 'inline'; document.getElementById('1707.00216v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1707.00216v1-abstract-full" style="display: none;"> The advent of nodal-line semi-metals, i.e. systems in which the conduction and valence bands cross each other along a closed trajectory (line or loop) inside the Brillouin zone, has opened up a new arena for the exploration of topological condensed matter in which, due to a vanishing density of states near the Fermi level, electron correlation effects may also play an important role. In spite of this conceptual richness however, material realization of nodal-line (loop) fermions is rare, with PbTaSe2, ZrSiS and PtSn4 the only promising known candidates. Here we report the synthesis and physical properties of a new compound PdSn4 that is isostructural with PtSn4 yet possesses quasiparticles with significantly enhanced effective masses. In addition, PdSn4 displays an unusual polar angular magnetoresistance which at a certain field orientation, varies linearly with field up to 55 Tesla. Our study suggests that, in association with its homologue PtSn4 whose low-lying excitations were recently claimed to possess Dirac node arcs, PdSn4 may be a promising candidate in the search for novel topological states with enhanced correlation effects. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1707.00216v1-abstract-full').style.display = 'none'; document.getElementById('1707.00216v1-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 July, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">6 figures, 1 table</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Materials 1, 064201 (2017) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1706.01744">arXiv:1706.01744</a> <span> [<a href="https://arxiv.org/pdf/1706.01744">pdf</a>, <a href="https://arxiv.org/ps/1706.01744">ps</a>, <a href="https://arxiv.org/format/1706.01744">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.96.064528">10.1103/PhysRevB.96.064528 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Topological Phase Transition Under Pressure in the Topological Nodal Line Superconductor PbTaSe$_2$ </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Xu%2C+C+Q">C. Q. Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Zhou%2C+W">W. Zhou</a>, <a href="/search/cond-mat?searchtype=author&query=Li%2C+B">Bin Li</a>, <a href="/search/cond-mat?searchtype=author&query=Han%2C+Z+D">Z. D. Han</a>, <a href="/search/cond-mat?searchtype=author&query=Qian%2C+B">B. Qian</a>, <a href="/search/cond-mat?searchtype=author&query=Dai%2C+J+H">J. H. Dai</a>, <a href="/search/cond-mat?searchtype=author&query=Cui%2C+H">Hengbo Cui</a>, <a href="/search/cond-mat?searchtype=author&query=Bangura%2C+A+F">A. F. Bangura</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F+C">F. C. Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+X">Xiaofeng Xu</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="1706.01744v1-abstract-short" style="display: inline;"> A first-order-like resistivity hysteresis is induced by a subtle structural transition under hydrostatic pressure in the topological nodal-line superconductor PbTaSe$_2$. This structure transition is quickly suppressed to zero at pressure $\sim$0.25 GPa. As a result, superconductivity shows a marked suppression, accompanied with fundamental changes in the magnetoresistance and Hall resistivity, su… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1706.01744v1-abstract-full').style.display = 'inline'; document.getElementById('1706.01744v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1706.01744v1-abstract-full" style="display: none;"> A first-order-like resistivity hysteresis is induced by a subtle structural transition under hydrostatic pressure in the topological nodal-line superconductor PbTaSe$_2$. This structure transition is quickly suppressed to zero at pressure $\sim$0.25 GPa. As a result, superconductivity shows a marked suppression, accompanied with fundamental changes in the magnetoresistance and Hall resistivity, suggesting a Lifshitz transition around $\sim$0.25 GPa. The first principles calculations show that the spin-orbit interactions partially gap out the Dirac nodal line around $K$ point in the Brillouin zone upon applying a small pressure, whilst the Dirac states around $H$ point are completely destroyed. The calculations further reveal a second structural phase transition under a pressure as high as $\sim$30 GPa, through which a transition from a topologically nontrivial phase to a trivial phase is uncovered, with a superconducting dome emerging under this high-pressure phase. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1706.01744v1-abstract-full').style.display = 'none'; document.getElementById('1706.01744v1-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 June, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">6 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 96, 064528 (2017) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1705.01685">arXiv:1705.01685</a> <span> [<a href="https://arxiv.org/pdf/1705.01685">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Materials Science">cond-mat.mtrl-sci</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevLett.119.136805">10.1103/PhysRevLett.119.136805 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Anomalous Acoustic Plasmon Mode from Topologically Protected States </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Jia%2C+X">Xun Jia</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+S">Shuyuan Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">Raman Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">Fang-Cheng Chou</a>, <a href="/search/cond-mat?searchtype=author&query=Wang%2C+W">Weihua Wang</a>, <a href="/search/cond-mat?searchtype=author&query=Kempa%2C+K">K. Kempa</a>, <a href="/search/cond-mat?searchtype=author&query=Plummer%2C+E+W">E. W. Plummer</a>, <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+J">Jiandi Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Zhu%2C+X">Xuetao Zhu</a>, <a href="/search/cond-mat?searchtype=author&query=Guo%2C+J">Jiandong Guo</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="1705.01685v3-abstract-short" style="display: inline;"> Plasmons, the collective excitations of electrons in the bulk or at the surface, play an important role in the properties of materials, and have generated the field of Plasmonics. We report the observation of a highly unusual acoustic plasmon mode on the surface of a three-dimensional topological insulator (TI), Bi2Se3, using momentum resolved inelastic electron scattering. In sharp contrast to or… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1705.01685v3-abstract-full').style.display = 'inline'; document.getElementById('1705.01685v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1705.01685v3-abstract-full" style="display: none;"> Plasmons, the collective excitations of electrons in the bulk or at the surface, play an important role in the properties of materials, and have generated the field of Plasmonics. We report the observation of a highly unusual acoustic plasmon mode on the surface of a three-dimensional topological insulator (TI), Bi2Se3, using momentum resolved inelastic electron scattering. In sharp contrast to ordinary plasmon modes, this mode exhibits almost linear dispersion into the second Brillouin zone and remains prominent with remarkably weak damping not seen in any other systems. This behavior must be associated with the inherent robustness of the electrons in the TI surface state, so that not only the surface Dirac states but also their collective excitations are topologically protected. On the other hand, this mode has much smaller energy dispersion than expected from a continuous media excitation picture, which can be attributed to the strong coupling with surface phonons. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1705.01685v3-abstract-full').style.display = 'none'; document.getElementById('1705.01685v3-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 September, 2017; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 3 May, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys. Rev. Lett. 119, 136805 (2017) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1705.00920">arXiv:1705.00920</a> <span> [<a href="https://arxiv.org/pdf/1705.00920">pdf</a>, <a href="https://arxiv.org/format/1705.00920">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Mesoscale and Nanoscale Physics">cond-mat.mes-hall</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1103/PhysRevB.100.115138">10.1103/PhysRevB.100.115138 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Planar Hall-effect, Anomalous planar Hall-effect, and Magnetic Field-Induced Phase Transitions in TaAs </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/cond-mat?searchtype=author&query=Zhang%2C+Q+R">Q. R. Zhang</a>, <a href="/search/cond-mat?searchtype=author&query=Zeng%2C+B">B. Zeng</a>, <a href="/search/cond-mat?searchtype=author&query=Chiu%2C+Y+C">Y. C. Chiu</a>, <a href="/search/cond-mat?searchtype=author&query=Schoenemann%2C+R">R. Schoenemann</a>, <a href="/search/cond-mat?searchtype=author&query=Memaran%2C+S">S. Memaran</a>, <a href="/search/cond-mat?searchtype=author&query=Zheng%2C+W">W. Zheng</a>, <a href="/search/cond-mat?searchtype=author&query=Rhodes%2C+D">D. Rhodes</a>, <a href="/search/cond-mat?searchtype=author&query=Chen%2C+K+-">K. -W. Chen</a>, <a href="/search/cond-mat?searchtype=author&query=Besara%2C+T">T. Besara</a>, <a href="/search/cond-mat?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/cond-mat?searchtype=author&query=Chou%2C+F">F. Chou</a>, <a href="/search/cond-mat?searchtype=author&query=McCandless%2C+G+T">G. T. McCandless</a>, <a href="/search/cond-mat?searchtype=author&query=Chan%2C+J+Y">J. Y. Chan</a>, <a href="/search/cond-mat?searchtype=author&query=Alidoust%2C+N">N. Alidoust</a>, <a href="/search/cond-mat?searchtype=author&query=Xu%2C+S+-">S. -Y. Xu</a>, <a href="/search/cond-mat?searchtype=author&query=Belopolski%2C+I">I. Belopolski</a>, <a href="/search/cond-mat?searchtype=author&query=Hasan%2C+M+Z">M. Z. Hasan</a>, <a href="/search/cond-mat?searchtype=author&query=Balakirev%2C+F+F">F. F. Balakirev</a>, <a href="/search/cond-mat?searchtype=author&query=Balicas%2C+L">L. Balicas</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="1705.00920v3-abstract-short" style="display: inline;"> We evaluate the topological character of TaAs through a detailed study of the angular, magnetic-field and temperature dependence of its magnetoresistivity and Hall-effect(s), and of its bulk electronic structure through quantum oscillatory phenomena. At low temperatures, and for fields perpendicular to the electrical current, we extract an extremely large Hall angle $螛_H$ at higher fields, that is… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1705.00920v3-abstract-full').style.display = 'inline'; document.getElementById('1705.00920v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1705.00920v3-abstract-full" style="display: none;"> We evaluate the topological character of TaAs through a detailed study of the angular, magnetic-field and temperature dependence of its magnetoresistivity and Hall-effect(s), and of its bulk electronic structure through quantum oscillatory phenomena. At low temperatures, and for fields perpendicular to the electrical current, we extract an extremely large Hall angle $螛_H$ at higher fields, that is $螛_H \sim 82.5^{\circ}$, implying a very pronounced Hall signal superimposed into its magnetoresistivity. For magnetic fields and electrical currents perpendicular to the \emph{c}-axis we observe a very pronounced planar Hall-effect, when the magnetic field is rotated within the basal plane. This effect is observed even at higher temperatures, i.e. as high as $T = 100$ K, and predicted recently to result from the chiral anomaly among Weyl points. Superimposed onto this planar Hall, which is an even function of the field, we observe an anomalous planar Hall-signal akin to the one reported for that is an odd function of the field. Below 100 K, negative longitudinal magnetoresistivity (LMR), initially ascribed to the chiral anomaly and subsequently to current inhomogeneities, is observed in samples having different geometries and contact configurations, once the large Hall signal is subtracted. Our measurements reveal a phase transition upon approaching the quantum limit that leads to the reconstruction of the FS and to the concomitant suppression of the negative LMR indicating that it is intrinsically associated with the Weyl dispersion at the Fermi level. For fields along the \emph{a}-axis it also leads to a pronounced hysteresis pointing to a field-induced electronic phase-transition. This collection of unconventional tranport observations points to the prominent role played by the axial anomaly among Weyl nodes. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1705.00920v3-abstract-full').style.display = 'none'; document.getElementById('1705.00920v3-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 November, 2018; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 2 May, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">13 pages, 8 figures, Supplemental File not 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 100, 115138 (2019) </p> </li> </ol> <nav class="pagination is-small is-centered breathe-horizontal" role="navigation" aria-label="pagination"> <a href="" class="pagination-previous is-invisible">Previous </a> <a href="/search/?searchtype=author&query=Sankar%2C+R&start=50" class="pagination-next" >Next </a> <ul class="pagination-list"> <li> <a href="/search/?searchtype=author&query=Sankar%2C+R&start=0" class="pagination-link is-current" aria-label="Goto page 1">1 </a> </li> <li> <a href="/search/?searchtype=author&query=Sankar%2C+R&start=50" class="pagination-link " aria-label="Page 2" aria-current="page">2 </a> </li> <li> <a href="/search/?searchtype=author&query=Sankar%2C+R&start=100" class="pagination-link " aria-label="Page 3" aria-current="page">3 </a> </li> </ul> </nav> <div class="is-hidden-tablet">  <span class="help" style="display: inline-block;"><a href="https://github.com/arXiv/arxiv-search/releases">Search v0.5.6 released 2020-02-24</a>  </span> </div> </div> </main> 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