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Dressed Feshbach molecules in the BEC-BCS crossover

M. W. J. Romans·H. T. C. Stoof
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Abstract

We present the RPA theory of the BEC-BCS crossover in an atomic Fermi gas near a Feshbach resonance that includes the relevant two-body atomic physics exactly. This allows us to determine the probability $Z$ for the dressed molecules in the Bose-Einstein condensate to be in the closed channel of the Feshbach resonance and to compare with the recent experiments of Partridge {\it et al.} [cond-mat/0505353] with $^{6}$Li. We determine for this extremely broad resonance also the condensate density of the dressed molecules throughout the BEC-BCS crossover.

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M. W. J. Romans, H. T. C. Stoof. 2005-06-13. Dressed Feshbach molecules in the BEC-BCS crossover. https://doi.org/10.1103/physrevlett.95.260407

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