Vortex nucleation in Bose-Einstein Condensates subject to light induced effective magnetic fields

TL;DR

This paper numerically investigates how vortices form in Bose-Einstein Condensates under light-induced effective magnetic fields, revealing the role of surface instabilities and field geometry in vortex nucleation.

Contribution

It introduces a method to generate and control effective magnetic fields in BECs using light, and demonstrates vortex nucleation mechanisms influenced by field inhomogeneity and trap asymmetry.

Findings

Vortex nucleation is triggered by surface excitation instabilities.

The shape of the applied magnetic field affects vortex configurations.

Surface excitations couple to the effective magnetic field in vortex formation.

Abstract

We numerically simulate vortex nucleation in a Bose-Einstein Condensate (BEC) subject to an effective magnetic field. The effective magnetic field is generated from the interplay between light with a non-trivial phase structure and the BEC, and can be shaped and controlled by appropriate modifications to the phase and intensity of the light. We demonstrate that the nucleation of vortices is seeded by instabilities in surface excitations which are coupled to by an asymmetric trapping potential (similar to the case of condensates subject to mechanical rotation) and show that this picture also holds when the applied effective magnetic field is not homogeneous. The eventual configuration of vortices in the cloud depends on the geometry of the applied field.