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Loss of superfluidity in a Bose-Einstein condensate on an optical lattice via a novel classical phase transition

Sadhan K. Adhikari
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Abstract

We predict the loss of superfluidity in a Bose-Einstein condensate (BEC) trapped in a combined optical and axially-symmetric harmonic potentials during a resonant collective excitation initiated by a periodic modulation of the atomic scattering length $a$, when the modulation frequency equals twice the radial trapping frequency or multiples thereof. This classical dynamical transition is marked by a loss of superfluidity in the BEC and a subsequent destruction of the interference pattern upon free expansion. Suggestion for future experiment is made.

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Sadhan K. Adhikari. 2003-02-10. Loss of superfluidity in a Bose-Einstein condensate on an optical lattice via a novel classical phase transition. https://doi.org/10.1016/s0375-9601(03)00059-8

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