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arXiv · 0806.4713

Equation of state and effective mass of the unitary Fermi gas in a 1D periodic potential

Gentaro Watanabe·Giuliano Orso·Franco Dalfovo·Lev P. Pitaevskii·Sandro Stringari
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Abstract

By solving the Bogoliubov -- de Gennes equations at zero temperature, we study the effects of a one-dimensional optical lattice on the behavior of a superfluid Fermi gas at unitarity. We show that, due to the lattice, at low densities the gas becomes highly compressible and the effective mass is large, with a consequent significant reduction of the sound velocity. We discuss the role played by the lattice in the formation of molecules and the emergence of two-dimensional effects in the equation of state. Predictions for the density profiles and for the frequency of the collective oscillations in the presence of harmonic trapping are also given.

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Gentaro Watanabe, Giuliano Orso, Franco Dalfovo, Lev P. Pitaevskii, Sandro Stringari. 2008-11-19. Equation of state and effective mass of the unitary Fermi gas in a 1D periodic potential. https://doi.org/10.1103/physreva.78.063619

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