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Condensation of Pairs of Fermionic Atoms Near a Feshbach Resonance

M. W. Zwierlein·C. A. Stan·C. H. Schunck·S. M. F. Raupach·A. J. Kerman·W. Ketterle
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Abstract

We have observed Bose-Einstein condensation of pairs of fermionic atoms in an ultracold ^6Li gas at magnetic fields above a Feshbach resonance, where no stable ^6Li_2 molecules would exist in vacuum. We accurately determined the position of the resonance to be 822+-3 G. Molecular Bose-Einstein condensates were detected after a fast magnetic field ramp, which transferred pairs of atoms at close distances into bound molecules. Condensate fractions as high as 80% were obtained. The large condensate fractions are interpreted in terms of pre-existing molecules which are quasi-stable even above the two-body Feshbach resonance due to the presence of the degenerate Fermi gas.

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M. W. Zwierlein, C. A. Stan, C. H. Schunck, S. M. F. Raupach, A. J. Kerman, W. Ketterle. 2004-03-12. Condensation of Pairs of Fermionic Atoms Near a Feshbach Resonance. https://doi.org/10.1103/physrevlett.92.120403

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