A5083035542- Iron-based superconductors research
- Topological Materials and Phenomena
- Advanced Condensed Matter Physics
- Rare-earth and actinide compounds
- Physics of Superconductivity and Magnetism
- 2D Materials and Applications
- Graphene research and applications
- Magnetic and transport properties of perovskites and related materials
- Corporate Taxation and Avoidance
- Electronic and Structural Properties of Oxides
- Superconductivity in MgB2 and Alloys
- Intellectual Capital and Performance Analysis
- Multiferroics and related materials
- Inorganic Chemistry and Materials
- Magnetic properties of thin films
- Photorefractive and Nonlinear Optics
- Advanced Thermoelectric Materials and Devices
- Quantum and electron transport phenomena
- Advanced Chemical Physics Studies
- Study of Mite Species
- Quantum many-body systems
- Chalcogenide Semiconductor Thin Films
- Aquatic Ecosystems and Phytoplankton Dynamics
- Advanced Materials Characterization Techniques
- Quantum, superfluid, helium dynamics
Chinese Academy of Sciences
2015-2024
Institute of Physics
2015-2024
University of Chinese Academy of Sciences
2011-2024
Fudan University
2018-2024
Hebei University of Chinese Medicine
2024
People's Liberation Army 401 Hospital
2024
National Laboratory for Superconductivity
2012-2024
Shaanxi Normal University
2024
Hebei Finance University
2024
Songshan Lake Materials Laboratory
2019-2023
Weyl fermions possess exotic properties and can act like magnetic monopoles. Researchers show that TaAs is a semimetal, demonstrating for the first time semimetals be identified experimentally.
A confluence of precise theoretical predictions shows that carefully fabricated three-dimensional (3D) semimetals can host a variety exotic phases dominated by topological constraints. This experimental review 3D addresses the role electronic structure and associated band crossings play in validating Dirac Weyl fermion descriptions have analogies with elementary particles quantum field theory. The importance Fermi arcs, nodal geometries, symmetry, spin-orbit coupling, dimensionality is...
Abstract A Weyl semimetal possesses spin-polarized band-crossings, called nodes, connected by topological surface arcs. The low-energy excitations near the crossing points behave same as massless fermions, leading to exotic properties like chiral anomaly. To have transport dominated nodes need locate nearly at chemical potential and enclosed pairs of individual Fermi surfaces with non-zero Chern numbers. Combining angle-resolved photoemission spectroscopy first-principles calculation, here...
In magnetic topological insulators (TIs), the interplay between order and nontrivial topology can induce fascinating quantum phenomena, such as anomalous Hall effect, chiral Majorana fermions axion electrodynamics. Recently, a great deal of attention has been focused on intrinsic TIs, where disorder effects be eliminated to large extent, which is expected facilitate emergence phenomena. despite intensive efforts, experimental evidence surface states (SSs) remains elusive. Here, by combining...
We demonstrate, using first-principles calculations, that the electronic structure of ${\mathrm{FeSe}}_{1\ensuremath{-}x}{\mathrm{Te}}_{x}\phantom{\rule{0.28em}{0ex}}(x=0.5)$ is topologically nontrivial and characterized by an odd ${\mathbb{Z}}_{2}$ invariant Dirac cone type surface states, in sharp contrast to end member FeSe $(x=0)$. This topological state induced enhanced three-dimensionality spin-orbit coupling due Te substitution (compared FeSe), a band inversion at $Z$ point Brillouin...
Topological semimetals are characterized by symmetry-protected band crossings, which can be preserved in different dimensions momentum space, forming zero-dimensional nodal points, one-dimensional lines, or even two-dimensional surfaces. Materials harboring points and lines have been experimentally verified, whereas experimental evidence of surfaces is still lacking. Here, using angle-resolved photoemission spectroscopy (ARPES), we reveal the coexistence Dirac bulk electronic structures...
Abstract The latest discovery of high temperature superconductivity near 80 K in La 3 Ni 2 O 7 under pressure has attracted much attention. Many proposals are put forth to understand the origin superconductivity. determination electronic structures is a prerequisite establish theories nickelates but still lacking. Here we report our direct measurement by high-resolution angle-resolved photoemission spectroscopy. Fermi surface and band observed compared with structure calculations. Strong...
MoTe$_2$ is an exfoliable transition metal dichalcogenide (TMD) which crystallizes in three symmetries, the semiconducting trigonal-prismatic $2H-$phase, semimetallic $1T^{\prime}$ monoclinic phase, and orthorhombic $T_d$ structure. The $2H-$phase displays a band gap of $\sim 1$ eV making it appealing for flexible transparent optoelectronics. $T_d-$phase predicted to possess unique topological properties might lead topologically protected non-dissipative transport channels. Recently, was...
Safety is essential for life. To survive, humans and other animals have developed sets of psychological physiological adaptations known as life history (LH) tradeoff strategies in response to various safety constraints. Evolutionarily selected LH turn regulate development behavior optimize survival under prevailing conditions. The present study tested hypotheses concerning based on a 6-year longitudinal sample 1,245 adolescents their parents from 9 countries. results revealed that, invariant...
Two-dimensional topological insulators with a large bulk band gap are promising for experimental studies of quantum spin Hall effect and spintronic device applications. Despite considerable theoretical efforts in predicting large-gap two-dimensional insulator candidates, none them have been experimentally demonstrated to full gap, which is crucial effect. Here, by combining scanning tunneling microscopy/spectroscopy angle-resolved photoemission spectroscopy, we reveal that ZrTe5 crystal...
We report the temperature evolution of detailed electronic band structure in FeSe single-crystals measured by angle-resolved photoemission spectroscopy (ARPES), including degeneracy removal $d_{xz}$ and $d_{yz}$ orbitals at $Γ$/Z M points, orbital-selective hybridization between $d_{xy}$ $d_{xz/yz}$ orbitals. The dependences splittings points are different, indicating that they controlled different order parameters. splitting point is closely related to structural transition attributed...
By combining angle-resolved photoemission spectroscopy and quantum oscillation measurements, we performed a comprehensive investigation on the electronic structure of LaSb, which exhibits near-quadratic extremely large magnetoresistance (XMR) without any sign saturation at magnetic fields as high 40 T. We clearly resolve one spherical intersecting-ellipsoidal hole Fermi surfaces (FSs) Brillouin zone (BZ) center Γ ellipsoidal electron FS BZ boundary X. The carriers calculated from enclosed...
Topological insulators (TIs) host novel states of quantum matter, distinguished from trivial by the presence nontrivial conducting boundary connecting valence and conduction bulk bands. Up to date, all TIs discovered experimentally rely on either time reversal or symmorphic mirror symmetry protect massless Dirac-like states. Very recently, it has been theoretically proposed that several materials are a new type protected nonsymmorphic symmetry, where glide-mirror can exotic surface fermions...
The mental health of the elderly is an important issue in area psychology. This study investigated effect intergeneration social support on subjective well-being 429 participants. Results suggested that support, self-esteem, and loneliness were significantly correlated to well-being. Structural equation modeling indicated self-esteem partially mediated These findings provided insights into elderly.
We performed a high-resolution angle-resolved photoemission spectroscopy study of the Tl0.63K0.37Fe1.78Se2 superconductor (Tc=29 K). show existence two electron-like bands at M(π, 0)-point which cross Fermi level similar wave vectors to form nearly circular surface pockets. observe isotropic ∼8.5 meV superconducting gap (2Δ/kBTc∼7) on these surfaces. Our analysis band structure around Brillouin zone centre reveals additional surfaces: very small one and larger with kF comparable surfaces M....
2D transition metal chalcogenides have attracted tremendous attention due to their novel properties and potential applications. Although dichalcogenides are easily fabricated layer-stacked bulk phase, monochalcogenides difficult obtain. Recently, a single atomic layer monochalcogenide (CuSe) with an intrinsic pattern of nanoscale triangular holes is on Cu(111). The first-principles calculations show that free-standing monolayer CuSe not stable, while hole-free endowed the Dirac nodal line...
We used angle-resolved photoemission spectroscopy to reveal directly the momentum distribution of superconducting gap in FeTe${}_{1\ensuremath{-}x}$Se${}_{x}$, which has simplest structure all Fe-based superconductors. found isotropic gaps on Fermi surfaces whose sizes can be fitted by a single function derived from strong coupling approach, promoting local antiferromagnetic exchange interactions as serious candidate for pairing origin.
Abstract Parity‐time symmetry plays an essential role for the formation of Dirac states in semimetals. So far, all experimentally identified topologically nontrivial semimetals (DSMs) possess both parity and time reversal symmetry. The realization magnetic topological DSMs remains a major issue material research. Here, combining angle‐resolved photoemission spectroscopy with density functional theory calculations, it is ascertained that band inversion induces ground state EuCd 2 As . result,...