Population of closed-channel molecules in trapped Fermi gases with broad Feshbach resonances.
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.
James Franck Institute and Department of Physics, University of Chicago, Illinois 60637, USA.
Qijin
Q
Chen
K
K
Levin