Influence of global features of a Bose-Einstein condensate on the vortex velocity

TL;DR

This paper investigates how the shape of the trapping potential influences vortex motion in a Bose-Einstein condensate, revealing the importance of global condensate features on vortex velocity through theoretical and simulation analyses.

Contribution

It introduces a simple relationship between vortex energy gradient and precession velocity, highlighting the impact of global condensate features on vortex dynamics.

Findings

Vortex velocity closely matches time evolution simulation results.

Velocity estimates from existing formulas show significant discrepancies.

Global features of the condensate significantly influence vortex precession velocity.

Abstract

We study the way in which the geometry of the trapping potential affects the vortex velocity in a Bose-Einstein condensate confined by a toroidal trap. We calculate the vortex precession velocity through a simple relationship between such a velocity and the gradient of the numerically obtained vortex energy. We observe that our results correspond very closely to the velocity calculated through time evolution simulations. However, we find that the estimates derived from available velocity field formulas present appreciable differences. To resolve such discrepancies, we further study the induced velocity field, analyzing the effect of global features of the condensate on such a field and on the precession velocity.