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Communications in Theoretical Physics

Analytical Expression of Ground State of Double-Well Bose–Einstein Condensates

Ai-Xi Chen, Li Deng

Published Feb 1, 2008• 0 citations
Publisher

Abstract

We derive an approximate analytical expression for the ground state of double-well BEC's, which reproduces highly accurately the numerical solution for the whole parameter regimes of the two-body repulsive interaction strength, the total number of atoms, and the hopping parameter.
DOI
10.1088/0253-6102/49/2/27

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We present a theoretical study of the ground state of a Bose-Einstein condensate with repulsive interparticle interactions in a double-well potential, using a restricted variational principle. Within such an approach, there is a transition from a single condensate to a fragmented condensate as the strength of the central barrier of the potential is increased. We determine the nature of this transition through an approximate analytic solution as well as a numerical solution of our model, in the regime where the interparticle interactions can be treated perturbatively. The degree of fragmentation of the condensate is characterized by the degrees of first- and second-order spatial coherence across the barrier.