Spin-driven spatial symmetry breaking of spinor condensates in a double-well

TL;DR

This paper investigates how spin interactions in an F=1 spinor Bose-Einstein condensate cause spatial symmetry breaking, leading to localization in one well, using mean-field and Hamiltonian models.

Contribution

It introduces a simplified effective Hamiltonian derived via perturbation theory to describe the symmetry-breaking transition in spinor condensates.

Findings

Spin effects induce spatial symmetry breaking.

Localization of condensate in one well occurs due to spin interactions.

Effective Hamiltonian captures the transition dynamics.

Abstract

The properties of an F=1 spinor Bose-Einstein condensate trapped in a double-well potential are discussed using both a mean-field two-mode approach and a simplified two-site Bose-Hubbard Hamiltonian. We focus in the region of phase space in which spin effects lead to a symmetry breaking of the system, favoring the spatial localization of the condensate in one well. To model this transition we derive, using perturbation theory, an effective Hamiltonian that describes N/2 spin singlets confined in a double-well potential.