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arXiv · 1401.1586

Strongly fluctuating fermionic superfluid in attractive π-flux Hubbard model

Ya-Jie Wu·Jiang Zhou·Su-Peng Kou
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Abstract

Ultracold atoms in optical lattice provides a platform to realize the superfluid (SF) state, a quantum order with paired charge-neutral fermions. In this paper, we studied SF state in the twodimensional attractive Hubbard model with pi-flux on each plaquette. The SF state in the pi-flux lattice model suffers very strong quantum fluctuations and the ground state becomes a possible quantum phase liquid state. In this phase, there exists the Cooper pairing together with a finite energy gap for the atoms, but no long range SF phase coherence exists at zero temperature. In addition, we discussed the properties of the SF vortices.

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Ya-Jie Wu, Jiang Zhou, Su-Peng Kou. 2014-01-15. Strongly fluctuating fermionic superfluid in attractive π-flux Hubbard model. https://doi.org/10.1103/physreva.89.013619

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