arXiv:1308.5922 · Physical Review A

Collective modes in the anisotropic unitary Fermi gas and the inclusion of a backflow term

Luca Salasnich, P. Comaron, M. Zambon, Flavio Toigo

Published Sep 9, 2013• 8 citations

Abstract

We study the collective modes of the confined unitary Fermi gas under anisotropic harmonic confinement as a function of the number of atoms. We use the equations of extended superfluid hydrodynamics, which take into account a dispersive von Weizs\"acker-like term [C. F. von Weizs\"acker, Z. Phys. 96, 431 (1935)] in the equation of state. We also discuss the inclusion of a backflow term in the extended superfluid Lagrangian and the effects of this anomalous term on sound waves and the Beliaev damping of phonons [S. T. Beliaev, Sov. Phys. JETP 7, 299 (1958)].

DOI: 10.1103/physreva.88.033610

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