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Superfluid current disruption in a chain of weakly coupled Bose-Einstein Condensates

F. S. Cataliotti·L. Fallani·F. Ferlaino·C. Fort·P. Maddaloni·M. Inguscio
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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 center of mass is larger than a critical velocity dependent on the tunnelling rate between adjacent sites.

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F. S. Cataliotti, L. Fallani, F. Ferlaino, C. Fort, P. Maddaloni, M. Inguscio. 2003-11-18. Superfluid current disruption in a chain of weakly coupled Bose-Einstein Condensates. https://doi.org/10.1088/1367-2630%2F5%2F1%2F371

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