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arXiv · 0710.5187

Phase Coherence and Superfluid-Insulator Transition in a Disordered Bose-Einstein Condensate

Yong P. Chen·J. Hitchcock·D. Dries·M. Junker·C. Welford·R. G. Hulet
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Abstract

We have studied the effects of a disordered optical potential on the transport and phase coherence of a Bose-Einstein condensate (BEC) of 7Li atoms. At moderate disorder strengths (V_D), we observe inhibited transport and damping of dipole excitations, while in time-of-flight images, random but reproducible interference patterns are observed. In-situ images reveal that the appearance of interference is correlated with density modulation, without complete fragmentation. At higher V_D, the interference contrast diminishes as the BEC fragments into multiple pieces with little phase coherence.

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Yong P. Chen, J. Hitchcock, D. Dries, M. Junker, C. Welford, R. G. Hulet. 2008-02-29. Phase Coherence and Superfluid-Insulator Transition in a Disordered Bose-Einstein Condensate. https://doi.org/10.1103/physreva.77.033632

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