A5101697860- Topological Materials and Phenomena
- 2D Materials and Applications
- Graphene research and applications
- Quantum and electron transport phenomena
- Organic and Molecular Conductors Research
- Rare-earth and actinide compounds
- Iron-based superconductors research
- Perovskite Materials and Applications
- Magnetism in coordination complexes
- Conducting polymers and applications
- Phase-change materials and chalcogenides
- Electronic and Structural Properties of Oxides
- Solid-state spectroscopy and crystallography
- Physics of Superconductivity and Magnetism
- Advanced Thermoelectric Materials and Devices
- Electron Spin Resonance Studies
- Machine Learning in Materials Science
- MXene and MAX Phase Materials
- Magnetic Properties of Alloys
- Theoretical and Computational Physics
- Optical and Acousto-Optic Technologies
- Advanced Condensed Matter Physics
- Computational Drug Discovery Methods
- Advanced Graph Neural Networks
- Topological and Geometric Data Analysis
Chinese Academy of Sciences
2015-2024
Huazhong University of Science and Technology
2000-2024
University of Chinese Academy of Sciences
2019-2024
Czech Academy of Sciences, Institute of Physics
2017-2024
Songshan Lake Materials Laboratory
2024
Southern University of Science and Technology
2022-2024
Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area
2023
Wuhan National Laboratory for Optoelectronics
2022
Institute of Physics
2015-2020
National Laboratory for Superconductivity
2019-2020
We have investigated the spin texture of surface Fermi arcs in recently discovered Weyl semimetal TaAs using spin- and angle-resolved photoemission spectroscopy. The experimental results demonstrate that are spin-polarized. measured fulfills requirement mirror time reversal symmetries is well reproduced by our first-principles calculations, which gives strong evidence for topologically nontrivial state TaAs. consistency between calculated further confirms distribution chirality nodes...
We present an infrared spectroscopy study of ZrTe$_5$, which confirms a recent theoretical proposal that this material exhibits temperature-driven topological quantum phase transition from weak to strong insulating state with intermediate Dirac semimetal around $T_p \simeq$ 138K. Our details the temperature evolution energy gap in bulk electronic structure. found closes $T_p$ where optical response characteristic signatures state, i.e. linear frequency-dependent conductivity extrapolating...
We introduce SignNet and BasisNet -- new neural architectures that are invariant to two key symmetries displayed by eigenvectors: (i) sign flips, since if $v$ is an eigenvector then so $-v$; (ii) more general basis symmetries, which occur in higher dimensional eigenspaces with infinitely many choices of eigenvectors. prove under certain conditions our networks universal, i.e., they can approximate any continuous function eigenvectors the desired invariances. When used Laplacian eigenvectors,...
Magnetic topological materials are a class of compounds with the underlying interplay nontrivial band topology and magnetic spin configuration. Extensive interest has been aroused due to their application potential involved an array exotic quantum states. With angle-resolved photoemission spectroscopy first-principles calculations, here we study electronic properties two Weyl semimetal candidates, PrAlSi SmAlSi. Though harbor distinct ground states (ferromagnetic antiferromagnetic for...
There is a long-standing confusion concerning the physical origin of anomalous resistivity peak in transition metal pentatelluride HfTe5. Several mechanisms, such as formation charge density wave or polaron, have been proposed, but so far no conclusive evidence has presented. In this work, we investigate unusual temperature dependence magneto-transport properties It found that three-dimensional topological Dirac semimetal state emerges only at around Tp (at which shows pronounced peak),...
The electronic and superconducting properties associated with the topologically non-trivial bands in Weyl semimetals have recently attracted much attention. We report microscopic of type-I semimetal TaAs measured by $^{75}$As nuclear magnetic (quadrupole) resonance under zero elevated fields over a wide temperature range up to 500 K. susceptibility Knight shift $K$ is found be negative at low strong field ($B$) dependence as ln$B$ $T$ = 1.56 Such nonlinear field-dependent magnetization can...
Two-dimensional materials offer opportunities for unravelling unprecedented ordered states at single layer limit. Among such states, Mott phase is rarely explored. Here, we report the in van der Waals chromium (II) iodide (CrI2) films. High quality CrI2 films with atomically flat surface and macro size are grown on graphitized 6H-SiC(0001) substrate by molecular beam epitaxy. By situ low temperature scanning tunneling microscopy spectroscopy (STM/STS), reveal that film has a band gap as...
Charge transport of topological semimetals has been in the focus intensive investigations because their non-trivial band topology. Heat these materials, on other hand, is largely unexplored and remains elusive. Here we report an observation unprecedented, giant magnetic quantum oscillations thermal conductivity prototypical Weyl semimetal TaAs. The are antiphase with oscillating electronic density states a pocket, amplitudes amount to two orders magnitude estimation based Wiedemann-Franz...
Large nonsaturating magnetoresistance has been observed in various materials and electron-hole compensation regarded as one of the main mechanisms. Here we present a detailed study angle-dependent Shubnikov--de Haas effect on large material pyrite-type ${\mathrm{PtBi}}_{2}$, which allows us to experimentally reconstruct its Fermi-surface structure extract physical properties each pocket. We find Fermi surface contains four types pockets Brillouin zone: three ellipsoidlike hole...
Tip-induced superconductivity at point contacts on the nonsuperconducting Weyl semimetal TaAs has been reported recently. Meanwhile, both main tetragonal phase and intergrown hexagonal of were identified to be topologically nontrivial according theoretical calculations. Here, we report observation two independent local superconducting states induced formed TaAs, which exhibit distinct temperature dependencies critical magnetic field ${H}_{c2}(T)$. A universal relationship between...
Gray arsenic is a two-dimensional semimetal material that has attracted much attention due to its rich and fascinating properties such as ultrahigh carrier mobility giant magnetoresistance properties. In this work, the structural electrical of gray under high pressure have been systematically explored. Two phase transitions, A7 simple cubic host-guest phase, were revealed at \ensuremath{\sim}28 \ensuremath{\sim}35 GPa, respectively. And transition completed \ensuremath{\sim}46 GPa....
In transition-metal dipnictides TmPn2 (Tm = Ta and Nb; Pn P, As, Sb), the origin of extremely large magnetoresistance (XMR) is yet to be studied by direct visualization experimental band structures. Here, using angle-resolved photoemission spectroscopy, we map out three-dimensional electronic structure NbAs2. The open-orbit topology contributes a non-negligible part Fermi surfaces (FSs), like that isostructural compound MoAs2, where open FS proposed likely explain XMR. We further demonstrate...
Novel materials incorporating electronic degrees of freedom other than charge, including spin, orbital, and valley freedom, have shown themselves to be great interest applicable potential. Recently, the multipolar attracted remarkable attention in correlated effects. In this work, we systematically study transport, magnetic, thermodynamic properties topological semimetal candidate PrBi framework crystalline electric field theory. Our results demonstrate ${\mathrm{\ensuremath{\Gamma}}}_{3}$...
The topological edge states of two-dimensional insulators with large energy gap furnish ideal conduction channels for dissipationless current transport. Transition metal tellurides XTe5 (X=Zr, Hf) are theoretically predicted to be large-gap and the experimental observations their bulk insulating in-gap have been reported, but nature these still remains further elucidated. Here, we report our low temperature scanning tunneling microscopy/spectroscopy study on single crystals HfTe5. We...
We report the transport properties of CaAs3 single crystal, which has been predicted to be a candidate for topological nodal-line semimetals. At ambient pressure, exhibits semiconducting behavior with small gap, while in some crystals containing tiny defects or impurities, large "hump" resistivity is observed around 230 K. By applying hydrostatic samples appear tendency towards metallic behavior, but not fully metallized up 2 GPa. Further high pressure studies are needed explore...
We report the extremely large magnetoresistance (XMR) property and Shubnikov--de Haas (SdH) oscillations in a quasi-one-dimensional material ${\mathrm{W}}_{2}{\mathrm{As}}_{3}$ single crystal, which shows good metallic behavior with typical residual resistivity ratio $\ensuremath{\rho}(300\phantom{\rule{4pt}{0ex}}\mathrm{K})/\ensuremath{\rho}(1.8\phantom{\rule{4pt}{0ex}}\mathrm{K})=1240$. In magnetic field, quick upturn saturates plateau as temperature cools down. At...
Abstract Interfaces between materials with different crystal structures and electronic properties offer an approach for creating controlling novel quantum states of matter, in which inversion symmetry breaking other effects at the boundaries may introduce additional states. Here observation superconductivity ≈3 K interface Weyl semimetal TaAs normal metal Ag is reported, as evidenced by soft‐point‐contact spectroscopy standard four‐probe resistance measurements. This from previous reports on...
We report transport properties in a ternary compound MoAlB single crystal. It shows metallic behavior with residual resistivity ratio of $\ensuremath{\rho}$(300 K)/$\ensuremath{\rho}$(2 K)=40. After applied magnetic fields, the quick upturn and saturates to plateau as temperature decreasing. At 2 K, magnetoresistance (MR) increases quadratically field reaches up $1650%$ ($B=14$ T) without saturation. The two-band fitting Hall conductivity suggests that unsaturated large quadratic MR was...
We report a study of fermiology, electrical anisotropy, and Fermi liquid properties in the layered ternary boride MoAlB, which could be peeled into two-dimensional (2D) metal borides (MBenes). By studying quantum oscillations comprehensive methods magnetization, magnetothermoelectric power, torque with first-principle calculations, we reveal three types bands this system, including two 2D-like electronic one complex three-dimensional-like hole band. Meanwhile, large out-of-plane anisotropy (...
Due to non-saturating magnetoresistance (MR) and the special compensation mechanism, Weyl semimetal TaAs single crystal has attracted considerable attention in condensed matter physics. Herein, we use maximum entropy mobility spectrum analysis (MEMSA) extract charge carrier information by fitting experimentally measured longitudinal transverse electric transport curves of TaAs. The types number bands are obtained without any hypothesis. Study temperature dependence shows details property...
Strategies to achieve higher upper-critical-field superconductors ({\mu}0Hc2(0)) are of great interest for both fundamental science and practical applications. While reducing the thickness two-dimensional (2D) materials a few layers significantly enhances {\mu}0Hc2(0) with accompanied potential unconventional pairing mechanisms, further dimensional reduction 1D compounds rarely exceeds expected Pauli limit. Here, we report discovery granular Ta-Te nanowire that becomes superconducting under...