Spin textures in slowly rotating Bose-Einstein Condensates

TL;DR

This paper investigates spin textures in slowly rotating Bose-Einstein condensates with different magnetic interactions, revealing distinct topological structures and their experimental signatures.

Contribution

It introduces a variational approach to analyze spin textures in rotating BECs, highlighting differences between ferromagnetic and antiferromagnetic interactions.

Findings

In ferromagnetic gases, angular momentum is carried by skyrmion textures.

In antiferromagnetic gases, angular momentum is carried by $ ext{pi}$-disclinations.

Core structures of $ ext{pi}$-disclinations can be imaged with polarized light.

Abstract

Slowly rotating spin-1 Bose-Einstein condensates are studied through a variational approach based upon lowest Landau level calculus. The author finds that in a gas with ferromagnetic interactions, such as $^{87}$Rb, angular momentum is predominantly carried by clusters of two different types of skyrmion textures in the spin-vector order parameter. Conversely, in a gas with antiferromagnetic interactions, such as $^{23}$Na, angular momentum is carried by $\pi$-disclinations in the nematic order parameter which arises from spin fluctuations. For experimentally relevant parameters, the cores of these $\pi$-disclinations are ferromagnetic, and can be imaged with polarized light.