Symmetry Breaking in Bose-Einstein Condensates

TL;DR

This paper explores how symmetry breaking occurs in Bose-Einstein condensates across various phenomena, clarifying the success of mean-field theories and the role of many-body effects in mesoscopic quantum systems.

Contribution

It provides a comprehensive analysis of symmetry breaking in BECs through four distinct cases, highlighting conditions where mean-field theories succeed or fail.

Findings

Mean-field theories effectively describe soliton and vortex phenomena in BECs.

Many-body effects become significant in spinor and dipolar BECs.

Symmetry breaking mechanisms vary across different BEC configurations.

Abstract

A gaseous Bose-Einstein condensate (BEC) offers an ideal testing ground for studying symmetry breaking, because a trapped BEC system is in a mesoscopic regime, and situations exist under which symmetry breaking may or may not occur. Investigating this problem can explain why mean-field theories have been so successful in elucidating gaseous BEC systems and when many-body effects play a significant role. We substantiate these ideas in four distinct situations: namely, soliton formation in attractive BECs, vortex nucleation in rotating BECs, spontaneous magnetization in spinor BECs, and spin texture formation in dipolar BECs.