Speed of sound in a superfluid Fermi gas in an optical lattice

2010/06/07 by Zlatko Koinov, Koinov, Z. G.
Physics and Astronomy · #Atomic and Subatomic Physics Research #Cold Atom Physics and Bose-Einstein Condensates #FOS: Physical sciences #Quantum, superfluid, helium dynamics #Strongly Correlated Electrons (cond-mat.str-el)

paper · pdf · doi:10.48550/arxiv.1006.1392

openalex publication_date 2010/06/07 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

A system of equal mixture of ⁶Li atomic Fermi gas of two hyperfine states loaded into a cubic three-dimensional optical lattice is studied assuming a negative scattering length (BCS side of the Feshbach resonance). When the interaction is attractive, fermionic atoms can pair and form a superfluid. The dispersion of the phonon-like mode and the speed of sound in the long-wavelength limit are obtained by solving the Bethe-Salpeter equations for the collective modes of the attractive Hubbard Hamiltonian.

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