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arXiv · 1406.1789

Relaxation dynamics in a strongly coupled Fermi superfluid

S. Khlebnikov
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Abstract

The key feature of time-dependent dynamics in a paired Fermi superfluid is the presence of a large number of independent degrees of freedom---the pairing amplitudes of fermions with different momenta. We argue that useful prototypes of this dynamics come from D-brane constructions of string theory. Using a specific example of that kind, we identify the mechanism by which a strongly coupled Fermi superfluid relaxes to equilibrium; it involves a wave of excitation in the momentum space, propagating from the Fermi surface towards the ultraviolet. For a sudden quench induced by a change in the fermion coupling, we find that the relaxation occurs rapidly, over only a few oscillations of the quasiparticle gap.

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S. Khlebnikov. 2014-06-06. Relaxation dynamics in a strongly coupled Fermi superfluid. https://arxiv.org/abs/1406.1789

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