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Expansion of a lithium gas in the BEC-BCS crossover

J. Zhang·E. G. M. Van Kempen·T. Bourdel·L. Khaykovich·J. Cubizolles·F. Chevy·M. Teichmann·L. Tarruell·S. J. J. M. F. Kokkelmans·C. Salomon
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Abstract

We report on experiments in $^6$Li Fermi gases near Feshbach resonances. A broad s-wave resonance is used to form a Bose-Einstein condensate of weakly bound $^6$Li$_2$ molecules in a crossed optical trap. The measured molecule-molecule scattering length of $170^{+100}_{-60}$ nm at 770 G is found in good agreement with theory. The expansion energy of the cloud in the BEC-BCS crossover region is measured. Finally we discuss the properties of p-wave Feshbach resonances observed near 200 Gauss and new s-wave resonances in the heteronuclear $^6$Li- $^7$Li mixture.

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J. Zhang, E. G. M. Van Kempen, T. Bourdel, L. Khaykovich, J. Cubizolles, F. Chevy, M. Teichmann, L. Tarruell, S. J. J. M. F. Kokkelmans, C. Salomon. 2004-10-07. Expansion of a lithium gas in the BEC-BCS crossover. https://doi.org/10.1063/1.1928857

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