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Response of a Fermi gas to time-dependent perturbations: Riemann-Hilbert approach at non-zero temperatures

Bernd Braunecker
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Abstract

We provide an exact finite temperature extension to the recently developed Riemann-Hilbert approach for the calculation of response functions in nonadiabatically perturbed (multi-channel) Fermi gases. We give a precise definition of the finite temperature Riemann-Hilbert problem and show that it is equivalent to a zero temperature problem. Using this equivalence, we discuss the solution of the nonequilibrium Fermi-edge singularity problem at finite temperatures.

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Bernd Braunecker. 2006-03-07. Response of a Fermi gas to time-dependent perturbations: Riemann-Hilbert approach at non-zero temperatures. https://doi.org/10.1103/physrevb.73.075122

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