arXiv:physics/0002041 · Physical Review Letters

Josephson Effects in Dilute Bose-Einstein Condensates

S. Giovanazzi, Augusto Smerzi, Stefano Fantoni

Published May 15, 2000• 160 citations

Abstract

We propose an experiment that would demonstrate the dc and ac Josephson effects in two weakly linked Bose-Einstein condensates. We consider a time-dependent barrier, moving adiabatically across the trapping potential. The phase dynamics are governed by a "driven-pendulum" equation, as in current-driven superconducting Josephson junctions. At a critical velocity of the barrier (proportional to the critical tunneling current), there is a sharp transition between the dc and ac regimes. The signature is a sudden jump of a large fraction of the relative condensate population. Analytical results are compared with a numerical integration of the Gross-Pitaevskii equation, in an experimentally realistic situation.

DOI: 10.1103/physrevlett.84.4521

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