Mean-field Dynamics of Spin-Orbit Coupled Bose-Einstein Condensates

TL;DR

This paper derives a generalized Gross-Pitaevskii equation to study the mean-field dynamics of spin-orbit coupled Bose-Einstein condensates, revealing diverse ground states and novel oscillation phenomena induced by SOC.

Contribution

It introduces a generic theoretical framework for analyzing many-body dynamics in spin-orbit coupled BECs, highlighting the impact of different laser configurations on condensate behavior.

Findings

Different laser setups lead to distinct mean field dynamics.

Multiple ground state phases such as stripe and phase separation are identified.

A new SOC-induced oscillation similar to Zitterbewegung is observed.

Abstract

Spin-orbit coupling (SOC), the interaction between the spin and momentum of a quantum particle, is crucial for many important condensed matter phenomena. The recent experimental realization of SOC in neutral bosonic cold atoms provides a new and ideal platform for investigating spin-orbit coupled quantum many-body physics. In this Letter, we derive a generic Gross-Pitaevskii equation as the starting point for the study of many-body dynamics in spin-orbit coupled Bose-Einstein condensates. We show that different laser setups for realizing the same SOC may lead to different mean field dynamics. Various ground state phases (stripe, phase separation, etc.) of the condensate are found in different parameter regions. A new oscillation period induced by the SOC, similar to the Zitterbewegung oscillation, is found in the center of mass motion of the condensate.