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Quantum-degenerate mixture of fermionic lithium and bosonic rubidium gases

C. Silber·S. Guenther·C. Marzok·B. Deh·Ph. W. Courteille·C. Zimmermann
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Abstract

We report on the observation of sympathetic cooling of a cloud of fermionic 6-Li atoms which are thermally coupled to evaporatively cooled bosonic 87-Rb. Using this technique we obtain a mixture of quantum-degenerate gases, where the Rb cloud is colder than the critical temperature for Bose-Einstein condensation and the Li cloud colder than the Fermi temperature. From measurements of the thermalization velocity we estimate the interspecies s-wave triplet scattering length |a_s|=20_{-6}^{+9} a_B. We found that the presence of residual rubidium atoms in the |2,1> and the |1,-1> Zeeman substates gives rise to important losses due to inelastic collisions.

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C. Silber, S. Guenther, C. Marzok, B. Deh, Ph. W. Courteille, C. Zimmermann. 2005-09-27. Quantum-degenerate mixture of fermionic lithium and bosonic rubidium gases. https://doi.org/10.1103/physrevlett.95.170408

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