Stable and unstable vortices in multicomponent Bose-Einstein condensates

TL;DR

This paper investigates the stability and dynamics of vortices in two-species Bose-Einstein condensates, revealing conditions for stability and complex behaviors when unstable, aligning with recent experimental observations.

Contribution

It provides a theoretical analysis of vortex stability in multicomponent condensates, matching experimental results and exploring vortex transfer and dynamics in unstable cases.

Findings

Only one vortex configuration is linearly stable, consistent with experiments.

Unstable vortices can transfer between species or exhibit complex dynamics.

Unstable vortices are not necessarily destroyed, but can persist with dynamic behavior.

Abstract

We study the stability and dynamics of vortices in two-species condensates as prepared in the recent JILA experiment (M. R. Andrews {\em et al.}, Phys. Rev. Lett. 83 (1999) 2498). We find that of the two available configurations, in which one specie has vorticity $m=1$ and the other one has $m=0$, only one is linearly stable, which agrees with the experimental results. However, it is found that in the unstable case the vortex is not destroyed by the instability, but may be transfered from one specie to the other or display complex spatiotemporal dynamics.