Boojums in Rotating Two-Component Bose-Einstein Condensates

TL;DR

This paper theoretically investigates boojum topological defects at the interface of two-component Bose-Einstein condensates with differing vortex structures, revealing their detailed density, vorticity, and pseudospin textures.

Contribution

It introduces a theoretical analysis of boojums in two-component BECs with contrasting intra-component interactions, highlighting their detailed structure and formation.

Findings

Boojum structures depend on the interface between phases with different vortex configurations.

Density distribution and superflow vorticity profiles of boojums are characterized.

Pseudospin textures of boojums are analyzed to understand their topological nature.

Abstract

A boojum is a topological defect that can form only on the surface of an ordered medium such as superfluid $^3$He and liquid crystals. We study theoretically boojums appearing between two phases with different vortex structures in two-component BECs where the intracomponent interaction is repulsive in one phase and attractive in the other. The detailed structure of the boojums is revealed by investigating its density distribution, effective superflow vorticity and pseudospin texture.