arXiv:cond-mat/0412454 · Physical Review Letters

Dynamics of the BCS-BEC Crossover in a Degenerate Fermi Gas

Marzena Hanna Szymańska, Benjamin D. Simons, Keith R. Burnett

Published May 3, 2005• 61 citations

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 magnetic field. We investigate the dynamics of the condensate order parameter and pair wave function for a range of field strengths. When the jump is sufficient to span the BCS to Bose-Einstein condensation crossover, we show that the rigidity of the momentum distribution precludes any atom-molecule oscillations in the entrance channel dominated resonances observed in 40K and 6Li. Focusing on material parameters tailored to the 40K Feshbach resonance at 202.1 G, we comment on the integrity of the fast sweep projection technique as a vehicle to explore the condensed phase in the crossover region.

DOI: 10.1103/physrevlett.94.170402

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