Superfluid transition in the attractive Hofstadter-Hubbard model

R. O. Umucalilar; M. Iskin

doi:10.1103/physreva.94.023611

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arXiv · 1605.07426

Superfluid transition in the attractive Hofstadter-Hubbard model

R. O. Umucalilar·M. Iskin

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Abstract

We consider a Fermi gas that is loaded onto a square optical lattice and subjected to a perpendicular artificial magnetic field, and determine its superfluid transition boundary by adopting a BCS-like mean-field approach in momentum space. The multi-band structure of the single-particle Hofstadter spectrum is taken explicitly into account while deriving a generalized pairing equation. We present the numerical solutions as functions of the artificial magnetic flux, interaction strength, Zeeman field, chemical potential, and temperature, with a special emphasis on the roles played by the density of single-particle states and center-of-mass momentum of Cooper pairs.

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R. O. Umucalilar, M. Iskin. 2016-05-24. Superfluid transition in the attractive Hofstadter-Hubbard model. https://doi.org/10.1103/physreva.94.023611

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