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arXiv · 2110.14073

Pair Fluctuation Effects on Quasiparticle Transport in Fermi Systems

Wei-Ting Lin·J. A. Sauls
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Abstract

The leading corrections to Fermi liquid theory for non-equilibrium quasiparticle transport near a Cooper instability arise from the virtual emission and absorption of incipient Cooper pairs. We formulate the corrections to the Landau-Boltzmann transport equation starting from Keldysh's field theory for non-equilibrium, strongly interacting Fermions. The theory is applicable to quasiparticle transport in conventional and unconventional superconductors, dense nuclear matter and the low temperature phases of liquid $^3$He. Validation of the theory is provided by our analysis, and quantitative agreement between theory and experiment, of the excess attenuation of zero sound in liquid $^3$He near the superfluid transition. We propose an additional experimental test of the theory based on the effects of a Zeeman field on the spectrum of pairing fluctuations for the Cooper instability in spin-triplet superfluids.

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Wei-Ting Lin, J. A. Sauls. 2021-10-26. Pair Fluctuation Effects on Quasiparticle Transport in Fermi Systems. https://arxiv.org/abs/2110.14073

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