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arXiv · 2304.07452

Instabilities of a Bose-Einstein condensate with mixed nonlinear and linear lattices

Jun Hong·Chenhui Wang·Yongping Zhang
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Abstract

Bose-Einstein condensates (BECs) in periodic potentials generate interesting physics on the instabilities of Bloch states. The lowest-energy Bloch states of BECs in pure nonlinear lattices are dynamically and Landau unstable, which breaks down BEC superfluidity. In this paper we propose to use an out-of-phase linear lattice to stabilize them. The stabilization mechanism is revealed by the averaged interaction. We further incorporate a constant interaction into BECs with mixed nonlinear and linear lattices, and reveal its effect on the instabilities of Bloch states in the lowest band.

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Jun Hong, Chenhui Wang, Yongping Zhang. 2023-04-15. Instabilities of a Bose-Einstein condensate with mixed nonlinear and linear lattices. https://doi.org/10.1103/physreve.107.044219

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