Nonequilibrium dynamics and thermodynamics of a degenerate Fermi gas across a Feshbach resonance

A. V. Andreev; V. Gurarie; L. Radzihovsky

doi:10.1103/physrevlett.93.130402

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Nonequilibrium dynamics and thermodynamics of a degenerate Fermi gas across a Feshbach resonance

A. V. Andreev·V. Gurarie·L. Radzihovsky

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Abstract

We consider a two-species degenerate Fermi gas coupled by a diatomic Feshbach resonance. We show that the resulting superfluid can exhibit a form of coherent BEC-to-BCS oscillations in response to a nonadiabatic change in the system's parameters, such as for example a sudden shift in the position of the Feshbach resonance. In the narrow resonance limit, the resulting soliton-like collisionless dynamics can be calculated analytically. In equilibrium the thermodynamics can be accurately computed across the full range of BCS-BEC crossover, with corrections controlled by the ratio of the resonance width to the Fermi energy.

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A. V. Andreev, V. Gurarie, L. Radzihovsky. 2004-04-30. Nonequilibrium dynamics and thermodynamics of a degenerate Fermi gas across a Feshbach resonance. https://doi.org/10.1103/physrevlett.93.130402

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