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Expansion of a lithium gas in the BEC-BCS crossover

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 نشر من قبل Frederic Chevy
 تاريخ النشر 2004
  مجال البحث فيزياء
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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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