Vortex Solutions in a Binary Immiscible Bose-Einstein Condensate

TL;DR

This paper investigates vortex solutions in a two-component immiscible Bose-Einstein condensate, employing a variational approach and numerical analysis to demonstrate the stability of vortex structures with an in-filling component.

Contribution

It introduces a variational method using a super-Gaussian approximation to model vortex solutions and analyzes their stability in a two-component BEC system.

Findings

Super-Gaussian function effectively approximates vortex solutions.

Vortex solutions are stable against small perturbations.

Numerical solutions confirm the variational approach's accuracy.

Abstract

We consider the mean-field vortex solutions and their stability within a two-component Bose Einstein condensate in the immiscible limit. A variational approach is employed to study a system consisting of a majority component which contains a single quantised vortex and a minority component which fills the vortex core. We show that a super-Gaussian function is a good approximation to the two-component vortex solution for a range of atom numbers of the in-filling component, by comparing the variational solutions to the full numerical solutions of the coupled Gross-Pitaevskii equations. We subsequently examine the stability of the vortex solutions by perturbing the in-filling component away from the centre of the vortex core, thereby demonstrating their stability to small perturbations.