Feshbach-Resonant Interactions in 40K and 6Li Degenerate Fermi Gases

Abstract

We theoretically examine a system of Fermi degenerate atoms coupled to bosonic molecules by a Feshbach resonance, focusing on the superfluid transition to a molecular Bose-Einstein condensate dressed by Cooper pairs of atoms. This problem raises an interest because it is unclear at present whether bimodal density distributions observed recently in 40-K and 6-Li are due to a condensate of bosonic molecules or fermionic atom pairs. As opposed to 40-K, we find that any measurable fraction of above-threshold bosonic molecules are necessarily absent for the 6-Li system in question, which strongly implicates Cooper pairs as the culprit behind its bimodal distributions.

arXiv comment4 pages, 2 figures, 25+ references, previously known as cond-mat/0409164 (it happens), accepted to PRL

References in corpus (20)

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• Condensation of Pairs of Fermionic Atoms Near a Feshbach Resonance
• Observation of Bose-Einstein Condensation of Molecules
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• Elastic and inelastic collisions of 6Li in magnetic and optical traps
• Cooper Pairing in Ultracold K-40 Using Feshbach Resonances
• Mean-Field Theory of Feshbach-Resonant Interactions in 85Rb Condensates
• Crossover temperature of Bose-Einstein condensation in an atomic Fermi gas
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• Atom-molecule equilibration in a degenerate Fermi gas with resonant interactions
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Cited by in corpus (10)

• The potential energy of a ${}^{40}$K Fermi gas in the BCS-BEC crossover
• Anisotropic Fermi Superfluid via p-wave Feshbach Resonance
• Conventional character of the BCS-BEC cross-over in ultra-cold gases of 40K
• Dressed Feshbach molecules in the BEC-BCS crossover
• Simple Mean-Field Theory for a Zero-Temperature Fermi Gas at a Feshbach Resonance
• Pairing Symmetry in the Anisotropic Fermi Superfluid under p-wave Feshbach Resonance
• Bogoliubov theory of Feshbach molecules in the BEC-BCS crossover
• A pseudo-potential analog for zero-range photoassociation and Feshbach resonance
• Adiabatic Phase Diagram of an Ultracold Atomic Fermi Gas with a Feshbach Resonance
• Adiabatic Phase Diagram on Degenerate Fermi Gas with Feshbach-Resonance