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Reaching Fermi degeneracy in two-species optical dipole traps

Roberto Onofrio·Carlo Presilla
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Abstract

We propose the use of a combined optical dipole trap to achieve Fermi degeneracy by sympathetic cooling with a different bosonic species. Two far-detuned pairs of laser beams focused on the atomic clouds are used to confine the two atomic species with different trapping strengths. We show that a deep Fermi degeneracy regime can be potentially achieved earlier than Bose-Einstein condensation, as discussed in the favorable situation of a ^6Li--^{23}Na mixture. This opens up the possibility of experimentally investigating a mixture of superfluid Fermi and normal Bose gases.

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Roberto Onofrio, Carlo Presilla. 2002-07-25. Reaching Fermi degeneracy in two-species optical dipole traps. https://doi.org/10.1103/physrevlett.89.100401

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