Dynamics of bubbles in a two-component Bose-Einstein condensate

TL;DR

This paper studies the complex dynamics of bubbles in a two-component Bose-Einstein condensate, revealing vortex formation, deformation, and vortex ring interactions through numerical simulations of the Gross--Pitaevskii equation.

Contribution

It provides new insights into bubble dynamics, vortex creation, and vortex ring interactions in two- and three-dimensional Bose-Einstein condensates using detailed numerical simulations.

Findings

Bubbles deform into ellipses and split into vortex fragments.

Vortex rings exhibit leapfrogging behavior.

Generation of Bénard--von Kármán vortex street in 2D.

Abstract

The dynamics of a phase-separated two-component Bose-Einstein condensate are investigated, in which a bubble of one component moves through the other component. Numerical simulations of the Gross--Pitaevskii equation reveal a variety of dynamics associated with the creation of quantized vortices. In two dimensions, a circular bubble deforms into an ellipse and splits into fragments with vortices, which undergo the Magnus effect. The B\'enard--von K\'arm\'an vortex street is also generated. In three dimensions, a spherical bubble deforms into toruses with vortex rings. When two rings are formed, they exhibit leapfrogging dynamics.