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arXiv:cond-mat/0505689 · Physical Review Letters

Population of Closed-Channel Molecules in Trapped Fermi Gases with Broad Feshbach Resonances

Qijin Chen, Kathryn Levin

Published Dec 28, 2005• 26 citations
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Abstract

We compute the fraction of closed-channel molecules in trapped atomic Fermi gases, over the entire range of accessible fields and temperatures. We use a two-channel model of Bardeen-Cooper-Schrieffer-Bose-Einstein-condensation crossover theory at general temperature , and show that this fraction provides a measure of the T-dependent pairing gap. Our calculations, containing no free parameters, are in good quantitative agreement with recent low- measurements in (6)Li. We present readily testable predictions for the dependencies of the closed-channel fraction on temperature and Fermi momentum.

DOI
10.1103/physrevlett.95.260406

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