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arXiv · cond-mat/0607274

Persistent current of atoms in a ring optical lattice

Andrey R. Kolovsky
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Abstract

We consider a small ensemble of Bose atoms in a ring optical lattice with weak disorder. The atoms are assumed to be initially prepared in a superfluid state with non-zero quasimomentum and, hence, may carry matter current. It is found that the atomic current persists in time for a low value of the quasimomentum but decays exponentially for a high (around one quater of the Brillouin zone) quasimomentum. The explanation is given in terms of low- and high-energy spectra of the Bose-Hubbard model, which we describe using the Bogoliubov and random matrix theories, respectively.

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Andrey R. Kolovsky. 2006-07-11. Persistent current of atoms in a ring optical lattice. https://doi.org/10.1088/1367-2630%2F8%2F9%2F197

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