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arXiv · 1308.5922

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

L. Salasnich·P. Comaron·M. Zambon·F. Toigo
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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 Weizsacker-like term in the equaton 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 Beliaev damping of phonons.

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L. Salasnich, P. Comaron, M. Zambon, F. Toigo. 2013-08-27. Collective modes in the anisotropic unitary Fermi gas and the inclusion of a backflow term. https://doi.org/10.1103/physreva.88.033610

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