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Exact solution of slow quench dynamics and nonadiabatic characterization of topological phases

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Chinese Physics B 2023年第8期32卷 171-180页

作者：邬睿房盼攀孙辰李福祥 School of Physics and Electronics Hunan UniversityChangsha 410082China

Previous studies have shown that the bulk topology of single-particle systems can be captured by the band inversion surface or by the spin inversion surface emerging on the time-averaged spin *** of the studies,however,are based on the single-particle picture even though the systems are fermionic and ***,we study the slow quench dynamics of topological systems with all the valence bands fully occupied,and show that the concepts of band inversion surface and spin inversion surface are still *** importantly,the many-particle nonadiabatic quench dynamics is shown to be reduced to a new and nontrivial three-level Landau-Zener *** nontrivial three-level Landau-Zener problem is then solved analytically by applying the integrability condition and symmetry considerations,and thus adds a new member to the few models that are exactly *** on the analytical results,the topological spin texture revealed by the time-averaged spin polarization can be applied to characterize the bulk topology and thus provides a direct comparison for future experiments.

关键词： Landau-Zener slow quench nonadiabatic

nonadiabatic Tapered Optical Fiber for Biosensor Applications

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Photonic Sensors 2012年第4期2卷 340-356页

作者： Hamid LATIFI Mohammad I. ZIBAII Seyed M. HOSSEINI Pedro JORGE Laser & Plasma Research Institute Shahid Beheshti University Evin Tehran Iran Department of Microbiology Faculty of Biological Sciences Shahid Beheshti University Evin Tehran Iran INESC Porto Rua do Campo Alegre 687 4169-007 Porto Portugal

A brief review on biconical tapered fiber sensors for biosensing applications is presented. A variety of configurations and formats of this sensor have been devised for label free biosensing based on measuring small refractive index changes. The biconical nonadiabatic tapered optical fiber offers a number of favorable properties for optical sensing, which have been exploited in several biosensing applications, including cell, protein, and DNA sensors. The types of these sensors present a low-cost fiber biosensor featuring a miniature sensing probe, label-free direct detection, and high sensitivity.

关键词： Biconical tapered optical fiber nonadiabatic refractive index biosensor

Three dimensional nonlinear shock waves in inhomogeneous plasmas with different size dust grains and external magnetized field

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Plasma Science and Technology 2020年第3期22卷 1-7页

作者： Liping ZHANG Jun FU Junyan SU School of Sciences Lanzhou University of TechnologyLanzhou 730050People’s Republic of China

The evolution of three dimensional nonlinear shock waves is investigated in a dusty plasma with inhomogeneous particles’density,nonadiabatic dust charge variation,external magnetized field and power law dust size *** this purpose,a modified nonlinear Korteweg-de Vries Burgers equation containing variable coefficients is obtained by reductive perturbation *** effects of inhomogeneity,dust size distribution,external magnetized field,dust charge variation and obliqueness parameter on shock structures are numerically examined in great ***,research results show that oscillatory shock waves and monotone shock waves exist and transform each other in this system.

关键词： shock structures inhomogeneity nonadiabatic dust charge fluctuation dust size distribution

A multi-dimensional microcanonical Monte Carlo study of S_0→T_1 intersystem crossing of isocyanic acid

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Science China Chemistry 2009年第11期52卷 1885-1891页

作者： ZHANG Feng1,2,FANG WeiHai1,LUO Yi2 & LIU RuoZhuang1 1 College of Chemistry,Beijing Normal University,Beijing 100875,China 2 Theoretical Chemistry,School of Biotechnology,Royal Institute of Technology,S-10691 Stockholm,Sweden 1. College of Chemistry Beijing Normal University Beijing 100875 China 2. Theoretical Chemistry School of Biotechnology Royal Institute of Technology S-10691 Stockholm Sweden

A general formula for the multi-dimensional Monte Carlo microcanonical nonadiabatic rate constant expressed in configuration space is applied to calculate the rate of intersystem crossing(ISC) between the ground(S0) and first excited triplet(T1) states for isocyanic ***-,two-and three-dimensional potential energy surfaces are constructed by coupled-cluster single-double CCSD calculations,which are used for Monte Carlo *** calculated S0→T1 ISC rate is in good agreement with experimental findings,which gives us a reason to believe that the multi-dimensional Monte Carlo microcanonical nonadiabatic rate theory is a very effective method for calculating nonadiabatic transition rate of a polyatomic molecule.

关键词： multi-dimensional Monte Carlo microcanonical nonadiabatic rate theory intersystem crossing isocyanic acid nonadiabatic transition

Field-dependent rate constant for intramolecular electron transfer reactions

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Chinese Science Bulletin 1995年第20期40卷 1698-1702页

作者：李象远田安民何福城鄢国森 Department of Chemistry Sichuan Union University Chengdu 610064 China

Electron transfer (ET) reactions are of great importance to nearly every subdiscipline of chemistry. Marcus classical model, quantum model treating the nuclei as a quantum system, and the semiclassical model neglecting the nuclear tunneling effects but taking the nonadiabatic transition between two electronic states into account, have been widely used in the kinetic research of ET reactions. For the symmetric double-well potential vs. the nuclear configuration Q along the reaction path (fig.1(a)), a semiclassical kinetic model

关键词： external electric field electron transfer nonadiabatic transition transition state rate constant.

Constraining Forces Causing the Meissner Effect

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Journal of Modern Physics 2017年第8期8卷 1134-1142页

作者： Ekkehard Krüger Institut für Materialwissenschaft Materialphysik Universit&auml t Stuttgart Stuttgart Germany

As shown in former papers, the nonadiabatic Heisenberg model presents a novel mechanism of Cooper pair formation which is not the result of an attractive electron-electron interaction but can be described in terms of quantum mechanical constraining forces. This mechanism operates in narrow, roughly half-filled superconducting bands of special symmetry and is evidently responsible for the formation of Cooper pairs in all superconductors. Here we consider this new mechanism within an outer magnetic field. We show that in the magnetic field the constraining forces produce Cooper pairs of non-vanishing total momentum with the consequence that an electric current flows within the superconductor. This current satisfies the London equations and, consequently, leads to the Meissner effect. This theoretical result is confirmed by the experimental observation that all superconductors, whether conventional or unconventional, exhibit the Meissner effect.

关键词： Superconductivity Meissner Effect nonadiabatic Heisenberg Model Time Inversion in a Magnetic Field Constraining Forces