Vortex line and ring dynamics in trapped Bose-Einstein condensates

TL;DR

This paper investigates vortex and vortex ring dynamics in trapped Bose-Einstein condensates through numerical simulations, revealing precession behaviors, oscillatory motions, and effects of dissipation on vortex rings.

Contribution

It provides new numerical insights into vortex and vortex ring behaviors in inhomogeneous BECs, including precession frequencies and oscillation characteristics.

Findings

Vortex precession around the condensate center was simulated and analyzed.

Vortex rings exhibit oscillatory motion around a maximum energy circle.

Dissipation increases oscillation amplitude, leading to vortex ring self-annihilation.

Abstract

Vortex dynamics in inhomogeneous Bose-Einstein condensates are studied numerically in two and three dimensions. We simulate the precession of a single vortex around the center of a trapped condensate, and use the Magnus force to estimate the precession frequency. Vortex ring dynamics in a spherical trap are also simulated, and we discover that a ring undergoes oscillatory motion around a circle of maximum energy. The position of this locus is calculated as a function of the number of condensed atoms. In the presence of dissipation, the amplitude of the oscillation will increase, eventually resulting in self-annihilation of the ring.