arXiv:cond-mat/0311410 · New Journal of Physics

Superfluid current disruption in a chain of weakly coupled Bose–Einstein condensates

F. S. Cataliotti, L. Fallani, Francesca Ferlaino, C. Fort, P. Maddaloni, M. Inguscio

Published Jun 13, 2003• 197 citations

Abstract

We report the experimental observation of the disruption of the superfluid atomic current flowing through an array of weakly linked Bose–Einstein condensates. The condensates are trapped in an optical lattice superimposed on a harmonic magnetic potential. The dynamical response of the system to a change of the magnetic potential minimum along the optical lattice axis goes from a coherent oscillation (superfluid regime) to a localization of the condensates in the harmonic trap ('classical' insulator regime). The localization occurs when the initial displacement is larger than a critical value or, equivalently, when the velocity of the wavepacket's centre of mass is larger than a critical velocity dependent on the rate of tunnelling between adjacent sites.

DOI: 10.1088/1367-2630/5/1/371

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