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Vortex-Peierls States in Optical Lattices

A. A. Burkov·Eugene Demler
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Abstract

We show that vortices, induced in cold atom superfluids in optical lattices, may order in a novel vortex-Peierls ground state. In such a state vortices do not form a simple lattice but arrange themselves in clusters, within which the vortices are partially delocalized, tunneling between classically degenerate configurations. We demonstrate that this exotic quantum many-body state is selected by an order-from-disorder mechanism for a special combination of the vortex filling and lattice geometry that has a macroscopic number of classically degenerate ground states.

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A. A. Burkov, Eugene Demler. 2006-05-10. Vortex-Peierls States in Optical Lattices. https://doi.org/10.1103/physrevlett.96.180406

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