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Dynamical vanishing of the order parameter in a fermionic condensate

Emil A. Yuzbashyan·Maxim Dzero
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Abstract

We analyze the dynamics of a condensate of ultra-cold atomic fermions following an abrupt change of the pairing strength. At long times, the system goes to a non-stationary steady state, which we determine exactly. The superfluid order parameter asymptotes to a constant value. We show that the order parameter vanishes when the pairing strength is decreased below a certain critical value. In this case, the steady state of the system combines properties of normal and superfluid states - the gap and the condensate fraction vanish, while the superfluid density is nonzero.

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Emil A. Yuzbashyan, Maxim Dzero. 2006-06-17. Dynamical vanishing of the order parameter in a fermionic condensate. https://doi.org/10.1103/physrevlett.96.230404

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