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Bose-representation for a strongly coupled nonequilibrim fermionic superfluid in a time-dependent trap

I. V. Tokatly
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Abstract

Using the functional integral formulation of a nonequilibrium quantum many-body theory we develop a regular description of a Fermi system with a strong attractive interaction in the presence of an external time-dependent potential. In the strong coupling limit this fermionic system is equivalent to a noequilibrium dilute Bose gas of diatomic molecules. We also consider a nonequilibrim strongly coupled Bardeen-Cooper-Schrieffer (BCS) theory and show that it reduces to the full nonlinear time-dependent Gross-Pitaevski (GP) equation, which determines an evolution of the condensate wave function.

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I. V. Tokatly. 2004-01-29. Bose-representation for a strongly coupled nonequilibrim fermionic superfluid in a time-dependent trap. https://doi.org/10.1103/physreva.70.043601

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