Dynamics of Topological Defects in a Rashba Spin-Orbit Coupled Bose-Einstein Condensate

TL;DR

This paper studies the formation and dynamics of topological vortices in a two-dimensional Rashba spin-orbit coupled Bose-Einstein condensate during a quench from zero-momentum to plane-wave phase, revealing Kibble-Zurek scaling behaviors.

Contribution

It provides the first detailed analysis of vortex dynamics and scaling laws in Rashba spin-orbit coupled BECs during phase quenches, connecting to Kibble-Zurek physics.

Findings

Vortices form with equal numbers of vortices and anti-vortices.

Vortex production time and number scale exponentially with quench rate.

Vortex decay follows a logarithmic law consistent with experiments.

Abstract

We investigate the quench dynamics of a two-dimensional Rashba spin-orbit coupled Bose-Einstein condensate. Our study focuses on quenching the system from a zero-momentum phase to a plane-wave phase. During this quench, topological defects emerge in the form of vortices. These vortices and anti-vortices exhibit a random spatial distribution with equal numbers, mirroring the core principles of Kosterlitz-Thouless physics. In a uniform system, we observe an exponential scaling of both the vortex production time and the vortex number with the quench rate, consistent with the conventional Kibble-Zurek mechanism. The decay of which adheres to a logarithmic law, aligning with experimental observations.