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Dynamics of the BCS-BEC crossover in a degenerate Fermi gas

M. H. Szymanska·B. D. Simons·K. Burnett
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Abstract

We study the short-time dynamics of a degenerate Fermi gas positioned near a Feshbach resonance following an abrupt jump in the atomic interaction resulting from a change of external magnetic field. We investigate the dynamics of the condensate order parameter and pair wavefunction for a range of field strengths. When the abrupt jump is sufficient to span the BCS to BEC crossover, we show that the rigidity of the momentum distribution precludes any atom-molecule oscillations in the entrance channel dominated resonances observed in the 40K and 6Li. Focusing on material parameters tailored to the 40K Feshbach resonance system at 202.1 gauss, we comment on the integrity of the fast sweet projection technique as a vehicle to explore the condensed phase in the crossover region

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M. H. Szymanska, B. D. Simons, K. Burnett. 2004-12-16. Dynamics of the BCS-BEC crossover in a degenerate Fermi gas. https://doi.org/10.1103/physrevlett.94.170402

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