A5100682781- Topological Materials and Phenomena
- Advanced Condensed Matter Physics
- Graphene research and applications
- 2D Materials and Applications
- Electronic and Structural Properties of Oxides
- Advanced Chemical Physics Studies
- Magnetic and transport properties of perovskites and related materials
- Magnetic properties of thin films
- Quantum, superfluid, helium dynamics
- Physics of Superconductivity and Magnetism
- Multiferroics and related materials
- Electron and X-Ray Spectroscopy Techniques
- Catalytic Processes in Materials Science
- Surface and Thin Film Phenomena
- Advanced X-ray Imaging Techniques
- Diamond and Carbon-based Materials Research
- Iron-based superconductors research
- Photorefractive and Nonlinear Optics
- Quantum many-body systems
- Catalysts for Methane Reforming
- Fullerene Chemistry and Applications
- Catalysis and Oxidation Reactions
- Rare-earth and actinide compounds
- Quantum and electron transport phenomena
- Heusler alloys: electronic and magnetic properties
Shanghai Institute of Microsystem and Information Technology
2015-2025
Shanghai Advanced Research Institute
2023-2025
Chinese Academy of Sciences
2015-2024
University of Chinese Academy of Sciences
2021-2024
Dalian University of Technology
2020-2024
Institute of Soil Science
2017-2022
Hiroshima University
2008-2021
Rutile RuO_{2} has been posited as a potential d-wave altermagnetism candidate, with predicted significant spin splitting up to 1.4 eV. Despite accumulating theoretical predictions and transport measurements, direct spectroscopic observation of remained elusive. Here, we employ spin- angle-resolved photoemission spectroscopy investigate the band structures polarization thin-film single-crystal RuO_{2}. Contrary expectations altermagnetism, our analysis indicates that RuO_{2}'s electronic...
The unidirectional alignment of graphene islands is essential to the synthesis wafer-scale single-crystal on Ge(110) surface, but underlying mechanism not well-understood. Here we report that necessary coalignment nucleating surface caused by presence step-pattern; show preannealed textureless appear nonpreferentially orientated, while surfaces with natural step pattern, all emerge coaligned. First-principles calculations and theoretical analysis reveal this different behaviors originate...
We have performed scanning tunneling microscopy and differential conductance (dI/dV) mapping for the surface of three-dimensional topological insulator Bi(2)Se(3). The fast Fourier transformation applied to dI/dV image shows an electron interference pattern near Dirac node despite general belief that backscattering is well suppressed in bulk energy gap region. comparison present experimental result with theoretical band structures occurs through scattering between states continuum states.
The experimental evidence is presented of the topological insulator state in PbBi2Te4. A single surface Dirac cone observed by angle-resolved photoemission spectroscopy with synchrotron radiation. Topological invariants Z2 are calculated from ab initio band structure to be 1;(111). two-dimensional isoenergy contours bulk energy gap found largest among known three-dimensional insulators. This opens a pathway achieving sufficiently large spin current density future spintronic devices.
Abstract Topological insulators (TIs) are a new quantum state of matter. Their surfaces and interfaces act as topological boundary to generate massless Dirac fermions with spin-helical textures. Investigation fermion dynamics near the point (DP) is crucial for future development spintronic devices incorporating insulators. However, research so far has been unsatisfactory because substantial overlap bulk valence band lack completely unoccupied DP. Here, we explore surface in TI Sb 2 Te 3 by...
Certain bacteria are resistant to antibiotics and can even transform in the environment. It is unclear how molecular mechanisms underlying resistance biotransformation processes vary under different environmental conditions. The objective of this study investigate tetracycline by Stenotrophomonas maltophilia strain DT1 various background nutrient Strain was exposed for 7 days with four conditions: no (NB), peptone (P), plus citrate (PC), glucose (PG). rate follows order PC > P PG NB ≈ 0....
Abstract The simple kagome-lattice band structure possesses Dirac cones, flat band, and saddle point with van Hove singularities in the electronic density of states, facilitating emergence various orders. Here we report a titanium-based kagome metal CsTi 3 Bi 5 where titanium atoms form network, resembling its isostructural compound CsV Sb . Thermodynamic properties including magnetization, resistance, heat capacity reveal conventional Fermi liquid behavior no signature superconducting or...
Abstract Magnetically doped topological insulators, possessing an energy gap created at the Dirac point through time-reversal-symmetry breaking, are predicted to exhibit exotic phenomena including quantized anomalous Hall effect and a dissipationless transport, which facilitate development of low-power-consumption devices using electron spins. Although several candidates magnetically insulators were demonstrated show long-range magnetic order, realization is so far restricted Cr-doped...
The half-Heusler compounds NiXSn (X = Ti, Zr, Hf) are regarded as examples of materials possessing excellent thermoelectric properties. We have studied their electronic structures by photoemission spectroscopy excited soft and hard X-ray synchrotron radiation. Although the overall features experimental valence band spectra well explained a calculated density states,"in-gap" states close to Fermi energy emerge due atomic disorder. These were further confirmed core-level appear be key for behavior.
A topological surface state that is protected physically under the Bi2Te3-like five-layer block has been revealed on Pb-based insulator (TI) PbBi4Te7 by bulk sensitive angle-resolved photoelectron spectroscopy (ARPES). Furthermore, conservation of spin polarization hidden states directly confirmed bulk-sensitive ARPES observation. This finding paves way to realize real spintronics devices TIs are operable in environment.
The structure sensitivity of CO2 activation in the presence H2 has been identified by ambient-pressure X-ray photoelectron spectroscopy (APXPS) on Ni(111) and Ni(110) surfaces under identical reaction conditions. Based APXPS results computer simulations, we propose that, around room temperature, hydrogen-assisted is major path Ni(111), while redox pathway prevails Ni(110). With increasing two pathways are activated parallel. While surface fully reduced to metallic state at elevated...
Fe 3 GaTe 2 , a recently discovered van der Waals ferromagnetic crystal with the highest Curie temperature and strong perpendicular magnetic anisotropy among two-dimensional (2D) materials, has attracted significant attention makes it promising candidate for next-generation spintronic applications. Compared GeTe which similar structure, mechanism of enhanced properties in is still unclear needs to be investigated. Here, by using x-ray circular dichroism measurements, we find that both Ga Te...
Abstract Topological insulators (TIs) possess spin-polarized Dirac fermions on their surface but unique properties are often masked by residual carriers in the bulk. Recently, (Sb 1− x Bi ) 2 Te 3 was introduced as a non-metallic TI whose carrier type can be tuned from n to p across charge neutrality point. By using time- and angle-resolved photoemission spectroscopy, we investigate ultrafast dynamics series of . The electronic recovery ∼10 ps at most bulk-metallic regime elongated >400...
Electron spin plays important roles in determining the physical and chemical properties of matter. However, measurements electron are poor quality, impeding development material sciences, because polarimeter has a low efficiency. Here, we show an imaging-type exchange-scattering with 6786 channels $8.5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}$ single channel As demonstration, fine structure electronic states bismuth (111) is investigated, for which strong Rashba-type splitting...
Recently, V-based kagome superconductors have emerged as a new research topic in condensed matter physics by intertwining superconductivity, charge density wave, and strong correlation. Here, the authors identify CsV${}_{3}$Sb${}_{5}$ Dirac nodal-line semimetal determining multiple nodal lines loops close to Fermi level with help of ARPES first-principles calculations. These could provide yet another source for obtaining larger Berry curvature and, hence, anomalous Hall conductivity, thus...
Abstract PrAlSi, a non‐centrosymmetric ferromagnetic Weyl semimetal candidate with Curie temperature of 17.8K, offers unique platform for exploring the interplay symmetry breaking and topological electronic structures. Up to now, fermion distribution as well their evolution across paramagnetic phase transition in PrAlSi has not been explored. Here, presence fermions is uncovered demonstrates that they can be manipulated through magnetic transition. The ab‐initio calculations indicate shift...
Along with the development of accelerator technology, synchrotron emittance has continuously decreased. This results in increased brightness, but also causes a heavy heat load on beamline optics. Recently, optical surfaces 0.1 nm micro-roughness and 0.05 µrad slope error (r.m.s.) have become commercially available surface distortions due to key factor determining performance, serious problem at modern radiation facilities. Here, APPLE-Knot undulators which can generate photons arbitrary...
Quantum confinement is a restriction on the motion of electrons in material to specific region, resulting discrete energy levels rather than continuous bands. In certain materials quantum could dramatically reshape electronic structure and properties surface with respect bulk. Here, recently discovered kagome superconductor CsV$_3$Sb$_5$ (A=K, Rb, Cs) family materials, we unveil dominant role determining their structure. Combining angle-resolved photoemission spectroscopy (ARPES) measurement...
Chalcogenide phase-change materials show strikingly contrasting optical and electrical properties, which has led to their extensive implementation in various memory devices. By performing spin-, time-, angle-resolved photoemission spectroscopy combined with the first-principles calculation, we report experimental results that crystalline phase of GeSb2Te4 is topologically nontrivial vicinity Dirac semimetal phase. The resulting linearly dispersive bulk Dirac-like bands cross Fermi level are...
5-nm thick Co4N layers capped with 3-nm Au were grown epitaxially on SrTiO3(001) substrates by molecular beam epitaxy using solid Co and a radio-frequency NH3 plasma. Spin orbital magnetic moments of the estimated x-ray circular dichroism (XMCD) measurements at 300 K. The site-averaged 3d spin moment is evaluated to be about 1.4 μB, which smaller than that predicted theoretically (1.58 μB). element-specific XMCD intensities for L3 edge N K show induced atoms.