微重力环境下冷原子物理及其应用

文章介绍了国际上微重力环境下冷原子物理及其应用的研究工作：空间原子钟、原子干涉仪、超冷原子物理和建议中的广义相对论的探索.文中简要介绍了中国科学院上海光学精密机械研究所在微重力环境下所进行的空间原子钟、玻色-爱因斯坦凝聚和原子芯片等研究工作.     

外势对物质波孤子的吸引和排斥

本文运用拉格朗日理论研究了物质波孤子在外势作用下的运动情况,主要讨论了初速度为零的孤子在势井和势垒中所表现出的不同行为,结果显示势垒能排斥孤子,势井能吸引孤子,并用数值模拟的方法使其得到了验证.     

磁偶极相互作用下玻色-爱因斯坦凝聚体中出现的奇特涡旋晶格结构

文章简要地介绍了玻色-爱因斯坦凝聚体中出现的涡旋和铬原子玻色-爱因斯坦凝聚体的实验研究进展,还介绍了文章作者的一项最新的理论工作.研究指出,由于铬原子磁偶极相互作用的影响,凝聚体中将出现奇特的各向异性的涡旋晶格结构     

Confinement and Zitterbewegung in a spin-orbit-coupled Bose-Einstein condensate with a spatially localized Raman coupling

Artificial spin-orbit coupling has been successfully implemented in many atomic experiments by so-called Raman addressing, and various interesting phenomena have already been investigated in such spin-orbit-coupled atomic systems. In this paper, we study spin-orbit-coupled Bose-Einstein condensates addressed by spatially localized Raman lasers. The localized Raman coupling effectively generates a spatial inhomogeneous spin-orbit coupling. The ground states of this system are spatially confined into the localization region. We excite Zitterbewegung dynamics by an experimentally realizable quench. By making advantage of Zitterbewegung, we propose to implement an atomic device to control over atoms.     

Phase Transition from the “Condensate” State

Mathematical Notes -     

The one-dimensional soliton state of Bose-Einstein condensate

Under certain conditions, the Bose-Einstein condensate confined in a two-dimensional harmonic trap is associated with a one-dimensional nonlinear Schrödinger equation and a soliton solution. The influence of the initial condition on the solution is discussed. The critical initial number of condensed atoms to maintain a soliton is evaluated. In the Li case, this number is of the order of thousand. The energy per particle of the solitons is also calculated.     

Two-component Bose-Einstein condensates

Recently, coupled systems of nonlinear Schrödinger equations have been used extensively to describe Bose-Einstein condensates. In this paper, we study the structure of vortices of the coupled nonlinear equations for two-component Bose-Einstein condensates (BEC) in a three-dimensional space. We show that vortices is 1-rectifiable set, and give its mean curvature. In particular, we show that large interspecies scattering length causes vortices for two-component BEC.     

QCD中等时方程的赝标介子解

本文讨论在背景场量子色动力学框架中的等时方程赝标介子解. 方程的积分核由微扰和非微扰贡献两部分组成．微拔部分是通常的单胶子交换图的贡献；非微扰部分的贡献来自于最低阶的夸克和胶子凝聚效应. 当输入合理的夸克质量参数和耦合常数时，可以得到与实验相符合的赝标介子谱．     

From two mesons and (V-A) weak currents to the standard model of quark and lepton interactions

This retrospective paper traces the conceptual evolution of two theories in which the author was involved—the two-meson theory (with H A Bethe) in 1947 and the universal (V-A) theory of weak interactions (with E C G Sudarshan) in 1957—into the present-day standard model of particle interactions. Part 1 is entitled ‘From the pion to QCD and pseudo-Goldstone bosons” and Part 2 “From the muon and neutrino to QFD and chiral anomalies’. Adapted from two lectures delivered at the University of Rochester in October, 1987.     

Propagators and Masses of Light Quarks

Based on Dyson-Schwinger equations in “rainbow“ approximation, fully dressed confining quark propagator is obtained, and then the masses of light quarks (mu, md, and ms) are derived from the fully dressed confining quark propagator. At the same time, the local and non-local quark vacuum condensates as well as the quark-gluon mixed condensate are also predicted. Furthermore, the quark masses are also deduced from the Gell-Mann-Oakes-Renner relation and chiral perturbative theory. The results from different methods are consistent with each other.