A5047462937- Topological Materials and Phenomena
- Physics of Superconductivity and Magnetism
- Advanced Condensed Matter Physics
- 2D Materials and Applications
- Magnetic and transport properties of perovskites and related materials
- Graphene research and applications
- Quantum and electron transport phenomena
- Rare-earth and actinide compounds
- Iron-based superconductors research
- Quantum, superfluid, helium dynamics
- Magnetic properties of thin films
- Transition Metal Oxide Nanomaterials
- High-pressure geophysics and materials
- Cold Atom Physics and Bose-Einstein Condensates
- Advancements in Semiconductor Devices and Circuit Design
- Multiferroics and related materials
- High-Temperature Coating Behaviors
- Magnetic Properties of Alloys
- Subcritical and Supercritical Water Processes
- Electronic and Structural Properties of Oxides
- Quantum Mechanics and Non-Hermitian Physics
- Inorganic Chemistry and Materials
- Spectral Theory in Mathematical Physics
- Atomic and Subatomic Physics Research
- Ga2O3 and related materials
University of Washington
2023-2025
California NanoSystems Institute
2017-2024
University of California, Los Angeles
2017-2024
China General Nuclear Power Corporation (China)
2021-2024
Southwest Petroleum University
2022-2023
Yantai University
2023
Astronomy and Space
2020-2022
UCLA Health
2021
Oak Ridge National Laboratory
2020
Harbin University of Science and Technology
2015
The recent discovered antiferromagnetic topological insulators in Mn-Bi-Te family with intrinsic magnetic ordering have rapidly drawn broad interest since its cleaved surface state is believed to be gapped, hosting the unprecedented axion states half-integer quantum Hall effect. Here, however, we show unambiguously by using high-resolution angle-resolved photoemission spectroscopy that a gapless Dirac cone at (0001) of MnBi$_2$Te$_4$ exists between bulk band gap. Such unexpected remains...
Abstract Magnetic topological insulators (TI) provide an important material platform to explore quantum phenomena such as quantized anomalous Hall effect and Majorana modes, etc. Their successful realization is thus essential for our fundamental understanding potential technical revolutions. By realizing a bulk van der Waals MnBi 4 Te 7 with alternating septuple [MnBi 2 ] quintuple [Bi 3 layers, we show that it ferromagnetic in plane but antiferromagnetic along the c axis out-of-plane...
The interplay between topology and magnetism is essential for realizing novel topological states including the axion insulator, magnetic Weyl semimetal, etc. An intrinsically ferromagnetic material with only bands at charge neutrality energy has so far remained elusive. By rationally designing natural heterostructure consisting of [MnBi2Te4] septuple layers [Bi2Te3] quintuple layers, we report MnBi8Te13 as first intrinsic clean low-energy band structure. Based on thermodynamic, transport...
Quantum geometry in condensed-matter physics has two components: the real part quantum metric and imaginary Berry curvature. Whereas effects of curvature have been observed through phenomena such as Hall effect two-dimensional electron gases anomalous (AHE) ferromagnets, rarely explored. Here, we report a nonlinear induced by dipole interfacing even-layered MnBi 2 Te 4 with black phosphorus. The switches direction upon reversing antiferromagnetic (AFM) spins exhibits distinct scaling that is...
Using single-crystal neutron diffraction, we present a systematic investigation of the crystal structure and magnetism van der Waals topological insulators ${\mathrm{MnBi}}_{2}{\mathrm{Te}}_{4}$ ${\mathrm{MnBi}}_{4}{\mathrm{Te}}_{7}$, where rich quantum states have been recently predicted observed. Structural refinements reveal that considerable Bi atoms occupied on Mn sites in both materials, distinct from previously reported antisite disorder. We show unambiguously orders...
The authors apply uniaxial strain on the layered kagome superconductor CsV${}_{3}$Sb${}_{5}$. They show that its charge density wave (CDW) and superconductivity (SC) transitions are dominated by change in $c$ axis, effect of explicit rotational symmetry breaking is negligible competition between CDW SC. Together with theoretical studies, they propose trilinear coupling ${M}_{1}^{+}$ ${L}_{2}^{\ensuremath{-}}$ phonon modes plays an important role CDW.
Most of the searches for Kitaev materials deal with $4d/5d$ magnets spin-orbit-coupled ${J=1/2}$ local moments such as iridates and $\alpha$-RuCl$_3$. Here we propose monoclinic YbCl$_3$ a Yb$^{3+}$ honeycomb lattice exploration Kiteav physics. We perform thermodynamic, $ac$ susceptibility, angle-dependent magnetic torque neutron diffraction measurements on single crystal. find that ion exhibits Kramers doublet ground state gives rise to an effective spin ${J_{\text{eff}}=1/2}$ moment. The...
The fine control of magnetism and electronic structure in a magnetic topological insulator is crucial order to realize various novel states including axion insulators, Weyl semimetals, Chern etc. Through crystal growth, transport, thermodynamic, neutron diffraction measurements, we show that under Sb doping the newly discovered intrinsic antiferromagnetic (AFM) ${\mathrm{MnBi}}_{4}{\mathrm{Te}}_{7}$ evolves from AFM ferromagnetic (FM) then ferrimagnetic. We attribute this formation...
Ever since the discovery of charge density wave (CDW) transition in kagome metal <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:msub><a:mrow><a:mi>CsV</a:mi></a:mrow><a:mrow><a:mn>3</a:mn></a:mrow></a:msub></a:mrow><a:mrow><a:msub><a:mrow><a:mi>Sb</a:mi></a:mrow><a:mrow><a:mn>5</a:mn></a:mrow></a:msub></a:mrow></a:math>, nature its symmetry breaking has been under intense debate. While evidence suggests that rotational is already broken at CDW temperature...
EuCd${}_{2}$As${}_{2}$ has been widely considered as a leading candidate for the ideal Weyl semimetal. However, recent study challenged this view by discovering substantial band gap in system. Here, authors successfully synthesize highly insulating EuCd${}_{2}$As${}_{2}$. It reveals decrease of anomalous Hall conductivity (AHC) orders magnitude carrier density decreases, contradicting expected behavior intrinsic AHC generated points. The results suggest that is magnetic semiconductor rather than
Abstract Non-volatile phase-change memory devices utilize local heating to toggle between crystalline and amorphous states with distinct electrical properties. Expanding on this kind of switching two topologically phases requires controlled non-volatile symmetries. Here, we report the observation reversible stable closely related crystal structures, remarkably electronic in near-room-temperature van der Waals ferromagnet Fe 5− δ GeTe 2 . We show that is enabled by ordering disordering site...
As the first intrinsic antiferromagnetic (AFM) topological insulator (TI), MnBi$_2$Te$_4$ has provided a material platform to realize various emergent phenomena arising from interplay of magnetism and band topology. Here by investigating (Mn$_{1-x}$Pb$_x$)Bi$_2$Te$_4$ $(0\leq x \leq 0.82)$ single crystals via x-ray, electrical transport, magnetometry neutron measurements, chemical analysis, external pressure, first-principles calculations, we reveal magnetic dilution effect on topology in...
Topological materials featuring exotic band structures, unconventional current flow patterns, and emergent organizing principles offer attractive platforms for the development of next-generation transformative quantum electronic technologies. The family MnBi2Te4 (Bi2Te3)n is naturally relevant in this context due to their nontrivial topology, tunable magnetism, recently discovered extraordinary transport behaviors. Despite numerous pioneering studies date, local magnetic properties remain an...
An intrinsic antiferromagnetic topological insulator ${\mathrm{MnBi}}_{2}{\mathrm{Te}}_{4}$ arises when intercalating a Mn-Te bilayer chain in insulator, ${\mathrm{Bi}}_{2}{\mathrm{Te}}_{3}$. We present observations on the inter- and intralayer phonon modes of generalized $\mathrm{Mn}\phantom{\rule{0.28em}{0ex}}{\mathrm{Bi}}_{2n}{\mathrm{Te}}_{3n+1}(n=1,2,3,4)$ family using cryogenic low-frequency Raman spectroscopy with various polarization configurations. Two peaks at 66...
Magnetism in two-dimensional (2D) materials has attracted considerable attention recently for both fundamental understanding of magnetism and its tunability towards device applications. The isostructural Fe3GeTe2 Fe3GaTe2 are two members the Fe-based van der Waals (vdW) ferromagnet family, but exhibit very different Curie temperatures (TC) 210 360 K, respectively. Here, by using angle-resolved photoemission spectroscopy density functional theory, we systematically compare electronic...
Atomically thin van der Waals materials provide a highly tunable platform for exploring emergent quantum phenomena in solid state systems. Due to their remarkable mechanical strength, one enticing tuning knob is strain. However, the weak strain transfer of graphite and hBN, which are standard components high-quality vdW devices, poses fundamental challenges high-strain experiments. Here, we investigate transmission less-explored orthorhombic crystals find robust up several percent at...