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Crossover from a molecular Bose-Einstein condensate to a degenerate Fermi gas

M. Bartenstein·A. Altmeyer·S. Riedl·S. Jochim·C. Chin·J. Hecker Denschlag·R. Grimm
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Abstract

We demonstrate a reversible conversion of a Li2 molecular Bose-Einstein condensate to a degenerate Fermi gas of atoms by adiabatically crossing a Feshbach resonance. By optical in situ imaging, we observe a smooth change of the cloud size in the crossover regime. On the Feshbach resonance, the ensemble is strongly interacting and the measured cloud size is 75(7)% of the one of a non-interacting zero-temperature Fermi gas. The high condensate fraction of more than 90% and the adiabatic crossover suggest our Fermi gas to be cold enough to form a superfluid.

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M. Bartenstein, A. Altmeyer, S. Riedl, S. Jochim, C. Chin, J. Hecker Denschlag, R. Grimm. 2004-02-28. Crossover from a molecular Bose-Einstein condensate to a degenerate Fermi gas. https://doi.org/10.1103/physrevlett.92.120401

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