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arXiv · 1805.09724

Period-doubled Bloch states in a Bose-Einstein condensate

Baoguo Yang·Pengju Tang·Xinxin Guo·Xuzong Chen·Biao Wu·Xiaoji Zhou
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Abstract

We study systematically the period-doubled Bloch states for a weakly interacting Bose-Einstein condensate in a one-dimensional optical lattice. This kind of state is of form $ψ_k=e^{ikx}ϕ_k(x)$, where $ϕ_k(x)$ is of period twice the optical lattice constant. Our numerical results show how these nonlinear period-doubled states grow out of linear period-doubled states at a quarter away from the Brillouin zone center as the repulsive interatomic interaction increases. This is corroborated by our analytical results. We find that all nonlinear period-doubled Bloch states have both Landau instability and dynamical instability.

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Baoguo Yang, Pengju Tang, Xinxin Guo, Xuzong Chen, Biao Wu, Xiaoji Zhou. 2018-05-24. Period-doubled Bloch states in a Bose-Einstein condensate. https://doi.org/10.1088/0256-307x%2F35%2F7%2F070301

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