Fermionic superfluidity and spontaneous superflows in optical lattices

Shi-Jie Yang; Shiping Feng

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arXiv · 1112.5496

Fermionic superfluidity and spontaneous superflows in optical lattices

Shi-Jie Yang·Shiping Feng

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Abstract

We study superfluidity of strongly repulsive fermionic atoms in optical lattices. The atoms are paired up through a correlated tunneling mechanism, which induces superfluidity when repulsive nearest-neighbor interactions are included in the Hubbard model. This paired superfluid is a metastable state which persists for a long time as the pair-broken process is severely suppressed. The mean-field phase diagram and low energy excitations are investigated in a square lattice system. Intriguingly, spontaneous superflows may appear in the ground state of a triangular optical lattice system due to antiferromagnetic frustration.

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Shi-Jie Yang, Shiping Feng. 2011-12-23. Fermionic superfluidity and spontaneous superflows in optical lattices. https://arxiv.org/abs/1112.5496

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