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

Gentaro Watanabe 1, 2, Giuliano Orso 3, Franco Dalfovo 4, Lev P. Pitaevskii 5, 6, Sandro Stringari 7

Physical Review A: Atomic, Molecular and Optical Physics 78 (2008) 063619

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.

  • 1. CNR INFM-BEC and Departement of physics,
    University of Trento
  • 2. RIKEN The Insititute of Chemical and Physical Research,
    RIKEN the insititute of chemical and physical research
  • 3. Laboratoire de Physique Théorique et Modèles Statistiques (LPTMS),
    CNRS : UMR8626 – Université Paris XI - Paris Sud
  • 4. CNR INFM BEC and Departement of physics,
    University of Trento
  • 5. Kapitza Institute for Physical Problems,
    Kapitza Institute for Physical Problems
  • 6. CNR INFM BEC and Departement of Physics,
    University of Trento
  • 7. CNR-INFM BEC Center,
    Universita di Trento