Zero sound in a two-dimensional dipolar Fermi gas

Zhen-Kai Lu 1, S. I. Matveenko 23, G. V. Shlyapnikov 245

Physical Review A 88 (2013) 033625

We study zero sound in a weakly interacting 2D gas of single-component fermionic dipoles (polar molecules or atoms with a large magnetic moment) tilted with respect to the plane of their translational motion. It is shown that the propagation of zero sound is provided by both mean field and many-body (beyond mean field) effects, and the anisotropy of the sound velocity is the same as the one of the Fermi velocity. The damping of zero sound modes can be much slower than that of quasiparticle excitations of the same energy. One thus has wide possibilities for the observation of zero sound modes in experiments with 2D fermionic dipoles, although the zero sound peak in the structure function is very close to the particle-hole continuum.

  • 1 : Max-Planck-Institut für Quantenoptik
    Max-Planck-Institut für Quantenoptik
  • 2 : Laboratoire de Physique Théorique et Modèles Statistiques (LPTMS)
    CNRS : UMR8626 – Université Paris XI - Paris Sud
  • 3 : L. D. Landau Institute for Theoretical Physics
    L. D. Landau Institute for Theoretical Physics
  • 4 : Van der Waals-Zeeman Institute
    University of Amsterdam
  • 5 : Kavli Institute for Theoretical Physics
    University of California, Santa Barbara