A5024191579- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Cold Atom Physics and Bose-Einstein Condensates
- Quantum, superfluid, helium dynamics
- Strong Light-Matter Interactions
- Quantum Information and Cryptography
- Quantum Computing Algorithms and Architecture
- Quantum Mechanics and Applications
- Quantum chaos and dynamical systems
- 2D Materials and Applications
- Quantum many-body systems
- Physics of Superconductivity and Magnetism
- Nonlinear Photonic Systems
- Perovskite Materials and Applications
- Quantum and electron transport phenomena
- Atomic and Subatomic Physics Research
- Advanced Fiber Laser Technologies
- Quantum optics and atomic interactions
- Advanced Thermodynamics and Statistical Mechanics
- Surface and Thin Film Phenomena
- Spectroscopy and Quantum Chemical Studies
- Theoretical and Computational Physics
- Quantum Mechanics and Non-Hermitian Physics
- Mechanical and Optical Resonators
- Graphene research and applications
Peking University
2015-2024
Central South University
2021-2024
Chinese Academy of Sciences
2006-2024
Shanghai Jiao Tong University
2016-2024
Collaborative Innovation Center of Quantum Matter
2015-2024
Ningbo Institute of Industrial Technology
2024
Taiyuan University of Science and Technology
2023
Mindray (China)
2023
Nanjing University
2021
Duke University
2021
A self-interacting two-level system depending on an external parameter is investigated. The most striking feature exhibited in this the presence of a nonzero tunneling probability adiabatic limit for large enough interaction strength. Possible experimental observation breakdown adiabaticity using Bose-Einstein condensate optical potential suggested.
The superfluidity of Bose-Einstein condensates in optical lattices are investigated. Apart from the usual Landau instability which occurs when a BEC flows faster than speed sound, can also suffer dynamical instability, resulting period doubling and other sorts symmetry breaking system. Such an may play crucial role dissipative motion trapped lattice recently observed [1].
A nonlinear Landau-Zener model was proposed recently to describe, among a number of applications, the nonadiabatic transition Bose-Einstein condensate between Bloch bands. Numerical analysis revealed striking phenomenon that tunneling occurs even in adiabatic limit as parameter $C$ is above critical value equal gap $V$ avoided crossing two levels. In this paper, we present analytical results give quantitative account breakdown adiabaticity by mapping quantum into classical Josephson...
Superflow of a Bose–Einstein condensate in an optical lattice is represented by Bloch wave, plane wave with periodic modulation the amplitude. We review theoretical results interaction effects energy dispersion waves and linear stability such waves. For sufficiently strong repulsion between atoms, lowest band develops loop at edge Brillouin zone, dramatic consequence finite probability Landau–Zener tunnelling even limit vanishing external force. Superfluidity can exist central region zone...
We investigate adiabatic evolution of quantum states as governed by the nonlinear Schrödinger equation and provide examples applications with a tunneling model for Bose-Einstein condensates. Our analysis not only spells out conditions eigenstates but also characterizes motion noneigenstates which cannot be obtained from former in absence superposition principle. find that Aharonov-Anandan phases play role classical canonical actions are conserved noneigenstates.
We study bright solitons in a Bose-Einstein condensate with spin-orbit coupling that has been realized experimentally. Both stationary and moving are found. The the ground states possess well-defined spin-parity, symmetry involving both spatial spin degrees of freedom; these real valued but not positive definite, number their nodes depends on strength coupling. For solitons, shapes found to change velocity due lack Galilean invariance system.
Recent advances in twisted van der Waals heterostructure superlattices have emerged as a powerful and attractive platform for exploring novel condensed matter physics due to the interplay between moiré potential Coulomb interactions. The act periodic confinement space capture interlayer excitons (IXs), resulting exciton arrays, which provide opportunities quantum emitters many-body physics. observation of IXs transition-metal dichalcogenide (TMD) heterostructures has recently been widely...
The stacking of twisted two-dimensional (2D) layered materials has led to the creation moiré superlattices, which have become a new platform for study quantum optics. strong coupling superlattices can result in flat minibands that boost electronic interactions and generate interesting strongly correlated states, including unconventional superconductivity, Mott insulating excitons. However, impact adjusting localizing excitons Van der Waals heterostructures yet be explored experimentally....
Moiré superlattices in twisted van der Waals materials offer a powerful platform for exploring light-matter interactions. The periodic moiré potentials can induce strongly correlated quantum phenomena that depend on the potential associated with interlayer coupling at interface. However, are primarily prepared by mechanical exfoliation and manual stacking, where transfer methods easily cause interfacial contamination, preparation of high-quality bilayer 2D small twist angles growth remains...
Creating highly effective electrocatalysts for the oxygen evolution reaction (OER) holds paramount importance in advancing carbon-neutral hydrogen production through water electrolysis. Recent research highlights crucial role of spin effects on OER, emphasizing that manipulation polarization is a promising strategy to augment OER kinetics. Here, we present core–shell heterostructure electrocatalyst, which leverages strong coupling interface between antiferromagnetic Co3O4 and NiFe-layered...
Nonlinear effects in the interference of Bose-Einstein condensates are studied using exact solutions one-dimensional nonlinear Schr\"odinger equation, which is applicable when lateral motion confined or negligible. With inverse scattering method, pattern as a problem with linear whose potential profiled by initial density distribution condensates. Our theory not only provides an analytical framework for quantitative predictions case, it also gives intuitive understanding some mysterious...
We study the superfluidity of a spin-orbit coupled Bose-Einstein condensate (BEC) by computing its Bogoliubov excitations, which are found to consist two branches: one is gapless and phonon-like at long wavelength; other typically gapped. These excitations imply that has new features: ({\it i}) due absence Galilean invariance, can no longer define critical velocity independent reference frame; ii}) depends not only on whether speed BEC exceeds value, but also {\it cross helicity} defined as...
Bloch waves and band of Bose-Einstein Condensates in optical lattices are studied. We provide further evidence for the loop structure band, compute critical values mean-field interaction strength Landau instability dynamical instability.
The generation of dark solitons in Bose-Einstein condensates with phase imprinting is studied by mapping it into the classic problem a damped driven pendulum. We provide simple but powerful scheme, designing imprint for various desired outcomes soliton generation. For given step, we derive formula number traveling each direction, and examine physics behind counterpropagating solitons.
We show with numerical computation and analysis that Bloch waves, at either the center or edge of Brillouin zone, a one dimensional nonlinear periodic system can be regarded as infinite chains composed fundamental gap solitons (FGSs). This composition relation between waves FGSs leads us to predict there are n families in nth band corresponding linear system, which is confirmed numerically. Furthermore, this extended construct class solutions similar but multiple periods.
We consider ultracold atoms subjected to a cavity-assisted two-photon Raman transition. The coupling gives rise effective spin-orbit interaction which couples the atom's center-of-mass motion its pseudospin degrees of freedom. Meanwhile, cavity photon field is dynamically affected by atom. This feedback between atom and photons leads dramatic modification atomic dispersion relation, further dynamical instability system. propose detect change in number as direct way demonstrate instability.
We show that a single dark soliton can exist in spin-orbit-coupled Fermi gas with high spin imbalance, where spin-orbit coupling favors uniform superfluids over nonuniform Fulde-Ferrell-Larkin-Ovchinnikov states, leading to excitations highly imbalanced gases. Above critical two topological Majorana fermions without interactions coexist inside soliton, paving way for manipulating through controlling solitons. At the transition point, atom density contrast across suddenly vanishes, suggesting...
A large body of knowledge about magnetism is attained from models interacting spins, which usually reside on magnetic ions. Proposals beyond the ionic picture are uncommon and seldom verified by direct observations in conjunction with microscopic theory. Here, using inelastic neutron scattering to study itinerant near-ferromagnet MnSi, we find that system's fundamental units interconnected, extended molecular orbitals consisting three Mn atoms each rather than individual atoms. This result...
We investigate the approach of time-dependent variational principle (TDVP) for one-dimensional spin-$J$ PXP model with detuning, which is relevant programmable Rydberg atom arrays. The manifold chosen as minimally entangled $\mathbb{Z}_K$ matrix-product-states (MPS). demonstrate that dynamics and error can be expressed rapidly convergent series in thermodynamic limit. In particular, $J=1/2$ limiting case $J\rightarrow \infty$, TDVP results become exact significantly simplified.
We propose a systematic procedure to directly extract the Eliashberg function for electron-phonon coupling from high-resolution angle-resolved photoemission measurement. The is successfully applied Be(10(-)10) surface, providing new insights into at this surface. method shown be robust against imperfections in experimental data and suitable wider applications.
Three different Pb films---free standing, on a semiconducting Ge(111) substrate, and metallic Cu(111) substrate---are studied with first-principles calculations. Our studies show that the properties of these films---surface energy, work function, lattice relaxation---oscillate strongly film thickness. The oscillation follows bilayer pattern interrupted by even-odd crossovers. However, positions crossovers separation between depend showing substrate plays an important role in properties. In...
The quantum tunneling effects between two silver plates are studied using the time dependent density functional theory. Our results show that depends mainly on separation and initial local field of interstice plates. smaller larger field, easier electrons tunnels through interstice. numerical calculation shows when is than 0.6 nm dramatically reduces enhancing ability nanoparticles.
We study vortex formation in a Bose-Einstein condensate rotating double-well potential. Besides the ordinary quantized vortices and elusive ghost vortices, "hidden" are found distributing along central barrier. These hidden invisible like but carry angular momentum. Moreover, their core size is not given by healing length, strongly influenced external find that Feynman's rule can be well satisfied only after including vortices. There no critical frequency for of while there one visible...