A5021976960- Topological Materials and Phenomena
- Quantum Mechanics and Non-Hermitian Physics
- Cold Atom Physics and Bose-Einstein Condensates
- Graphene research and applications
- Astrophysics and Star Formation Studies
- Quantum chaos and dynamical systems
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Spectral Theory in Mathematical Physics
- Quantum optics and atomic interactions
- Quantum and electron transport phenomena
- Atomic and Subatomic Physics Research
- Quantum, superfluid, helium dynamics
- Quantum many-body systems
- Quantum Information and Cryptography
- Advanced Condensed Matter Physics
- Mechanical and Optical Resonators
- Galaxies: Formation, Evolution, Phenomena
- Differential Equations and Boundary Problems
- Nonlinear Photonic Systems
- 2D Materials and Applications
- Gamma-ray bursts and supernovae
- Advanced Fiber Laser Technologies
- Laser-Matter Interactions and Applications
- Physics of Superconductivity and Magnetism
Tsinghua University
2016-2025
Beijing Tsinghua Chang Gung Hospital
2019-2025
Northeast Agricultural University
2024
Dalian University of Technology
2024
Xinjiang University
2024
Anyang Eye Hospital
2024
Chinese Academy of Sciences
2006-2023
Qingdao Institute of Bioenergy and Bioprocess Technology
2019-2023
Yantai University
2023
Northeastern University
2022
The bulk-boundary correspondence is among the central issues of non-Hermitian topological states. We show that a previously overlooked "non-Hermitian skin effect" necessitates redefinition invariants in generalized Brillouin zone. resultant phase diagrams dramatically differ from usual Bloch theory. Specifically, we obtain diagram Su-Schrieffer-Heeger model, whose zero modes are determined by non-Bloch winding number instead Bloch-Hamiltonian-based number. Our work settles issue breakdown...
The relation between chiral edge modes and bulk Chern numbers of quantum Hall insulators is a paradigmatic example bulk-boundary correspondence. We show that the are not strictly tied to defined by non-Hermitian Bloch Hamiltonian. This breakdown conventional correspondence stems from non-Bloch-wave behavior eigenstates (non-Hermitian skin effect), which generates pronounced deviations phase diagrams theory. introduce non-Bloch faithfully predict modes. theory backed up open-boundary energy...
One of the unique features non-Hermitian Hamiltonians is skin effect, namely, that eigenstates are exponentially localized at boundary system. For open quantum systems, a short-time evolution can often be well described by effective Hamiltonians, while long-time dynamics calls for Lindblad master equations, in which Liouvillian superoperators generate time evolution. In this Letter, we find exhibit and uncover its unexpected physical consequences. It shown effect dramatically shapes...
We present multiband photometry of 185 type-Ia supernovae (SNe Ia), with over 11,500 observations. These were acquired between 2001 and 2008 at the F. L. Whipple Observatory Harvard-Smithsonian Center for Astrophysics (CfA). This sample contains largest number homogeneously observed reduced nearby SNe Ia (z ≲ 0.08) published to date. It more than doubles sample, bringing SN cosmology point where systematic uncertainties dominate. Our natural system has a precision ≲0.02 mag in BVRIr'i' ≲0.04...
The topology of non-Hermitian systems is drastically shaped by the skin effect, which leads to generalized bulk-boundary correspondence and non-Bloch band theory. essential part in formulations a general computable definition topological invariants. In this Letter, we introduce construction invariants based directly on real-space wave functions, provides straightforward approach for determining topology. As an illustration, apply formulation several representative models systems, efficiently...
We present UBVRI photometry of 44 Type Ia supernovae (SNe Ia) observed from 1997 to 2001 as part a continuing monitoring campaign at the Fred Lawrence Whipple Observatory Harvard-Smithsonian Center for Astrophysics. The data set comprises 2190 observations and is largest homogeneously reduced sample SNe date, nearly doubling number well-observed, nearby with published multicolor CCD light curves. large U-band unique addition, important connections high redshift. decline rate SN curves...
We introduce two-dimensional topological insulators in proximity to high-temperature cuprate or iron-based superconductors as platforms of Majorana Kramers pairs zero modes. The proximity-induced pairing at the helical edge state insulator serves a Dirac mass, whose sign changes sample corner because symmetry high-${T}_{c}$ superconductors. This changing naturally creates each pair modes protected by time-reversal symmetry. Conceptually, this is topologically trivial superconductor-based...
In topological semimetals, the valance band and conduction meet at zero-dimensional nodal points or one-dimensional rings, which are protected by topology symmetries. this Rapid Communication, we introduce ``nodal-link semimetals'', host linked rings in Brillouin zone. We put forward a general recipe based on Hopf map for constructing models of nodal-link semimetals. The consequences ring linking Landau levels Floquet properties investigated.
We propose general topological order parameters for interacting insulators in terms of the Green's function at zero frequency. They provide an unified description various including quantum anomalous Hall and time reversal invariant four, three two dimensions. Since only frequency is used, these can be evaluated efficiently by most numerical analytical algorithms strongly systems.
We study dynamical instability and chiral symmetry breaking in three-dimensional Weyl semimetals, which turns semimetals into ``axion insulators.'' Charge density waves (CDWs) are found to be the natural consequence of breaking. The phase mode this charge wave state is identified as axion, couples an electromagnetic field topological $\ensuremath{\theta}\mathbf{E}\ifmmode\cdot\else\textperiodcentered\fi{}\mathbf{B}$ term. One our main results that strings'' can realized (screw or edge)...
Weyl semimetals and nodal line are characterized by linear band touching at zero-dimensional points one-dimensional lines, respectively. We predict that a circularly polarized light drives into semimetals. The Floquet thus obtained tunable the incident light, which enables investigations of them in highly controllable manner. transition from to is accompanied emergence large anomalous Hall conductivity. Our predictions experimentally testable transport measurement film samples or pump-probe...
Dirac semimetals have attracted extensive attentions in recent years. It has been theoretically suggested that many-body interactions may drive exotic phase transitions, spontaneously generating a mass for the nominally massless electrons. So far, signature of interaction-driven transition lacking. In this work, we report high-magnetic-field transport measurements semimetal candidate ZrTe5. Owing to large g factor ZrTe5, Zeeman splitting can be observed at magnetic field as low 3 T. Most...
Topological nodal-line semimetals are characterized by one-dimensional lines of band crossing in the Brillouin zone. In contrast to nodal points, can be topologically nontrivial configurations. this paper, we study simplest forms line, namely, a single line taking shape knot We introduce generic construction for various "nodal-knot semimetals", which yields trefoil and other more complicated knots The knotted-unknotted transitions reconnections also studied. Our work brings theory subject...
Parity-time (PT)-symmetric Hamiltonians have widespread significance in non-Hermitian physics. A PT-symmetric Hamiltonian can exhibit distinct phases with either real or complex eigenspectrum, while the transition points between, so-called exceptional points, give rise to a host of critical behaviors that holds great promise for applications. For spatially periodic systems, PT symmetries are commonly characterized and observed line Bloch band theory, dwelling Brillouin zone. Here, nonunitary...
We unveil an unexpected non-Hermitian phenomenon, dubbed edge burst, in quantum dynamics. Specifically, a class of walk periodic lattices with open boundary condition, exceptionally large portion loss occurs at the system boundary. The physical origin this burst is found to be interplay between two unique phenomena: skin effect and imaginary gap closing. Furthermore, we establish universal bulk-edge scaling relation underlying burst. Our predictions are experimentally accessible various...
The parity-time ($\mathcal{PT}$) symmetry of a non-Hermitian Hamiltonian leads to real (complex) energy spectrum when the non-Hermiticity is below (above) threshold. Recently, it has been demonstrated that skin effect generates new type $\mathcal{PT}$ symmetry, dubbed non-Bloch featuring unique properties such as high sensitivity boundary condition. Despite its relevance wide range lattice systems, general theory still lacking for this generic phenomenon even in one spatial dimension. Here,...
The non-Hermitian skin effect dramatically reshapes the energy bands of systems, meaning that usual Bloch band theory is fundamentally inadequate as their characterization. non-Bloch theory, in which concept Brillouin zone generalized, has been widely applied to investigate systems one spatial dimension. However, its generalization higher dimensions challenging. Here, we develop a formulation and arbitrary dimensions, based on natural geometrical object known amoeba. Our provides general...
Decoherence is a major obstacle to the preparation of topological order in noisy intermediate-scale quantum devices. Here, we show that decoherence can also give rise new types order. Specifically, construct concrete examples by proliferating fermionic anyons toric code via local channels. The resulting mixed states retain long-range entanglement, which manifests nonzero entanglement negativity, though memory destroyed decoherence. By comparison with gapless spin liquid pure states,...
We propose a topological order parameter for interacting insulators, expressed in terms of the full Green's functions system. show that it is exactly quantized time reversal invariant insulator, and can be experimentally measured through magneto-electric effect. This applied to both disordered systems, used determining their phase diagrams.
Periodically driven (Floquet) systems have been under active theoretical and experimental investigations. This paper aims at a systematic study in the following aspects of Floquet systems: (i) formulation topological invariants based on cooperation topology symmetries. Topological are constructed for ten symmetry classes all spatial dimensions, both homogeneous (Floquet insulators superconductors) defects. Meanwhile, useful representative Dirac Hamiltonians obtained studied. (ii) A general...
Abstract Classical wave fields are real-valued, ensuring the states at opposite frequencies and momenta to be inherently identical. Such a particle–hole symmetry can open up new possibilities for topological phenomena in classical systems. Here we show that historically studied two-dimensional (2D) magnetoplasmon, which bears gapped bulk gapless one-way edge near-zero frequency, is topologically analogous 2D p + ip superconductor with chiral Majorana zero modes. We further predict type of...