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arXiv · 1308.6710

Ferromagnetism in a two-component Bose-Hubbard model with a synthetic spin-orbit coupling

Jize Zhao·Shijie Hu·Jun Chang·Ping Zhang·Xiaoqun Wang
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Abstract

We study the effect of the synthetic spin-orbit coupling in a two-component Bose-Hubbard model in one dimension by employing the density-matrix renormalization group method. A ferromagnetic long-range order emerges in both Mott insulator and superfluid phases resulting from the spontaneous breaking of the $Z_2$ symmetry, when the spin-orbit coupling term becomes comparable to the hopping kinetic energy and the inter-component interaction is smaller than the intra-one as well. This novel effect is expected to be detectable with the present realization of the synthetic spin-orbit coupling in experiments.

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Jize Zhao, Shijie Hu, Jun Chang, Ping Zhang, Xiaoqun Wang. 2014-04-18. Ferromagnetism in a two-component Bose-Hubbard model with a synthetic spin-orbit coupling. https://doi.org/10.1103/physreva.89.043611

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