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Sub-Doppler Laser Cooling of Fermionic K-40 Atoms

G. Modugno·C. Benko·P. Hannaford·G. Roati·M. Inguscio
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Abstract

We report laser cooling of fermionic K-40 atoms, with temperatures down to (15 +/- 5) microK, for an enriched sample trapped in a MOT and additionaly cooled in optical molasses. This temperature is a factor of 10 below the Doppler-cooling limit and corresponds to an rms velocity within a factor of two of the lowest realizable rms velocity (~3.5v rec) in 3D optical molasses. Realization of such low atom temperatures, up to now only accessible with evaporative cooling techniques, is an important precursor to producing a degenerate Fermi gas of K-40 atoms.

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G. Modugno, C. Benko, P. Hannaford, G. Roati, M. Inguscio. 1999-08-06. Sub-Doppler Laser Cooling of Fermionic K-40 Atoms. https://doi.org/10.1103/physreva.60.r3373

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