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Instability of a superfluid Bose gas induced by a locked thermal gas in an optical lattice

Satoru Konabe·Tetsuro Nikuni
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Abstract

We use a dissipative Gross-Petaevskii equation derived from the Bose-Hubbard Hamiltonian to study the effect of the thermal component on the stability of a current-carrying superfluid state of a Bose gas in an optical lattice potential. We explicitly show that the superfluid state becomes unstable at certain quasi-momentum of the condensate due to a thermal component which is locked by an optical lattice potential. It is shown that this instability coincides with the Landau instability derived from the GP equation.

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Satoru Konabe, Tetsuro Nikuni. 2005-12-01. Instability of a superfluid Bose gas induced by a locked thermal gas in an optical lattice. https://doi.org/10.1088/0953-4075%2F39%2F10%2Fs10

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