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Fermi-Bose quantum degenerate ^40 K - ^87 Rb mixture with attractive interaction

G. Roati·F. Riboli·G. Modugno·M. Inguscio
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Abstract

We report on the achievement of simultaneous quantum degeneracy in a mixed gas of fermionic ^40 K and bosonic ^87 Rb. Potassium is cooled to 0.3 times the Fermi temperature by means of an efficient thermalization with evaporatively cooled rubidium. Direct measurement of the collisional cross-section confirms a large interspecies attraction. This interaction is shown to affect the expansion of the Bose-Einstein condensate released form the magnetic trap, where it is immersed in the Fermi sea.

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G. Roati, F. Riboli, G. Modugno, M. Inguscio. 2002-08-07. Fermi-Bose quantum degenerate ^40 K - ^87 Rb mixture with attractive interaction. https://doi.org/10.1103/physrevlett.89.150403

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