Bose-Einstein Condensates on slightly asymmetric double-well potentials

TL;DR

This paper provides an analytical study of symmetry breaking and quantum fluctuations in Bose-Einstein condensates within slightly asymmetric double-well potentials, focusing on the transition from Josephson to self-trapping regimes.

Contribution

It introduces simple formulas linking condensate fragmentation to quantum fluctuations during the Josephson to self-trapped transition in an asymmetric double-well system.

Findings

Derived expressions for ground state properties of attractive bosons.

Established a relationship between fragmentation and quantum fluctuations.

Analyzed the transition mechanisms in asymmetric double-well potentials.

Abstract

An analytical insight into the symmetry breaking mechanisms underlying the transition from Josephson to self-trapping regimes in Bose-Einstein condensates is presented. We obtain expressions for the ground state properties of the system of a gas of attractive bosons modelized by a two site Bose-Hubbard hamiltonian with an external bias. Simple formulas are found relating the appearance of fragmentation in the condensate with the large quantum fluctuations of the population imbalance occurring in the transition from the Josephson to the self-trapped regime.