Giant vortex and Skyrmion in a rotating two-species Bose-Einstein condensate

TL;DR

This paper uses numerical simulations to study the formation of giant vortices and Skyrmions in a rotating two-species Bose-Einstein condensate with unequal particle numbers, revealing new topological structures.

Contribution

It introduces the first detailed simulation of giant vortices and Skyrmions in a rotating two-species BEC with unequal particle numbers, highlighting their formation mechanisms.

Findings

Majority species form a central vortex when rotation exceeds a critical speed.

Minority species are expelled to the outskirts, creating a vortex hole.

A novel annular Skyrmion appears at the interface between species.

Abstract

Numerical simulations are performed for a rotating two-species Bose condensate confined by a harmonic potential. The particle numbers of each species are unequal. When the rotational speed exceeds a critical value, the majority species reside in the center of the potential while the minority species is pushed out to the outskirts, forming a giant vortex hole to contain the majority species. A novel annular Skyrmion forms at the interface of the two species.