arXiv:1110.0311 · Europhysics Letters (EPL)

Supersonic and subsonic shock waves in the unitary Fermi gas

Luca Salasnich

Published Nov 1, 2011• 33 citations

Abstract

We investigate shock waves in the unitary Fermi gas by using the zero-temperature equations of superfluid hydrodynamics. We obtain analytical solutions for the dynamics of a localized perturbation of the uniform gas. These supersonic bright and subsonic dark solutions produce, after a transient time, an extremely large (divergent) density gradient: the shock. We calculate the time of formation of the shock and also simulate the space-time behavior of the waves by solving generalized hydrodynamic equations, which include a reliable dispersive regularization of the shock. We find that the shock spreads into wave ripples whose properties crucially depend on the chosen initial configuration.

DOI: 10.1209/0295-5075/96/40007

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