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arXiv:cond-mat/0308104

Josephson Current Counterflow in Atomic Bose-Einstein Condensates

E. Sakellari, Nick P. Proukakis, M. L. Leadbeater, Charles S. Adams

Published Aug 6, 2003• 0 citations
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Abstract

Josephson weak links in superconductors can be engineered such that the phase difference across the junction is $π$ ($π$-junction),leading to the reversal of the current. The conditions under which the analogous effect of supercurrent counterflow can be achieved in a double-well atomic Bose-Einstein condensate are investigated. It is shown that this effect is observable for condensates up to a few thousand atoms, which are initially prepared in an anti-symmetric '$π$-state' and subsequently subjected to a uniformly increasing magnetic field gradient. This effect is found to be only weakly-dependent on trap geometry, and can be observed in both attractive and repulsive condensates.

DOI
10.48550/arxiv.cond-mat/0308104

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