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Observation of dynamical instability for a Bose-Einstein condensate in a moving 1D optical lattice

L. Fallani·L. De Sarlo·J. E. Lye·M. Modugno·R. Saers·C. Fort·M. Inguscio
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Abstract

We have experimentally studied the unstable dynamics of a harmonically trapped Bose-Einstein condensate loaded into a 1D moving optical lattice. The lifetime of the condensate in such a potential exhibits a dramatic dependence on the quasimomentum state. This is unambiguously attributed to the onset of dynamical instability, after a comparison with the predictions of the Gross-Pitaevskii theory. Deeply in the unstable region we observe the rapid appearance of complex structures in the atomic density profile, as a consequence of the condensate phase uniformity breakdown.

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L. Fallani, L. De Sarlo, J. E. Lye, M. Modugno, R. Saers, C. Fort, M. Inguscio. 2004-04-02. Observation of dynamical instability for a Bose-Einstein condensate in a moving 1D optical lattice. https://doi.org/10.1103/physrevlett.93.140406

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