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All-Optical Production of a Degenerate Fermi Gas

S. R. Granade·M. E. Gehm·K. M. O'Hara·J. E. Thomas
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Abstract

We achieve degeneracy in a mixture of the two lowest hyperfine states of $^6$Li by direct evaporation in a CO$_2$ laser trap, yielding the first all-optically produced degenerate Fermi gas. More than $10^5$ atoms are confined at temperatures below $4 μ$K at full trap depth, where the Fermi temperature for each state is $8 μ$K. This degenerate two-component mixture is ideal for exploring mechanisms of superconductivity ranging from Cooper pairing to Bose condensation of strongly bound pairs.

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S. R. Granade, M. E. Gehm, K. M. O'Hara, J. E. Thomas. 2002-03-01. All-Optical Production of a Degenerate Fermi Gas. https://doi.org/10.1103/physrevlett.88.120405

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