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Landau and Dynamical Instabilities of the Superflow of Bose-Einstein Condensates in Optical Lattices

Biao Wu·Qian Niu
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Abstract

The superfluidity of Bose-Einstein condensates in optical lattices are investigated. Apart from the usual Landau instability which occurs when a BEC flows faster than the speed of sound, the BEC can also suffer a dynamical instability, resulting in period doubling and other sorts of symmetry breaking of the system. Such an instability may play a crucial role in the dissipative motion of a trapped BEC in an optical lattice recently observed [1].

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Biao Wu, Qian Niu. 2001-04-06. Landau and Dynamical Instabilities of the Superflow of Bose-Einstein Condensates in Optical Lattices. https://doi.org/10.1103/physreva.64.061603

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