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arXiv · 2001.06757

Repulsive Fermi gases in a two-dimensional lattice with non-Abelian gauge fields

Yi-Xiang Wang·Fuxiang Li
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Abstract

Motivated by the recent experiment realizing bidirectional spin-orbit-coupled Bose-Einstein condensates (BEC), we theoretically explore the properties of repulsive fermions in the two-dimensional (2D) optical lattice with such non-Abelian gauge fields. Within the mean-field level, we find a novel phase of topological antiferromagnetic (TAFM) order which incorporates both the non-trivial topology due to spin-flip hopping and spontaneous symmetry breaking (SSB) for the in-plane spin order. We argue that the appearance of such a phase is generic for repulsive fermions in Chern bands achieved through spin-orbit coupling. Our work paves the way for further studies of fermionic generalization of 2D non-Abelian spin-orbit-coupled quantum gases.

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Yi-Xiang Wang, Fuxiang Li. 2020-01-19. Repulsive Fermi gases in a two-dimensional lattice with non-Abelian gauge fields. https://doi.org/10.1209/0295-5075%2F123%2F37001

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