报告题目:Quantum Spin Dynamics in a Normal Bose Gas with Spin-orbit Coupling

报告人：张世忠 （香港大学物理系）

报告时间：2019年7月4日（星期四）上午9:30 — 11:00

报告地点：新物理楼5楼多功能厅

报告摘要：

We discuss the spin dynamics of a two-component Bose gas with spin-orbit coupling realised in cold atom experiments. Taking into account of the effect originally discovered by Leggett and Rice, we derive a set of hydrodynamic equations that describes the spin evolution in both adiabatic and diabatic regimes. We show that exact solution corresponding to persistent spin helix exists and discuss the stability of spin helical structure with general wave vector. In the adiabatic regime, the transverse spin decays parabolically in the short-time limit and exponentially in the long-time limit, depending on initial polarisation. In contrast, in the diabatic regime, transverse spin density and current oscillate in a way similar to the charge-current oscillation in an undamped LC circuit. Finally, using realistic experimental parameters for ⁸⁷Rb, we show that the time scales for spin dynamics is of order of milliseconds to a few seconds and can hopefully be observed experimentally.

邀请人： 王宇 教授