Atoms Laser-Cooled Below the Doppler-Cooling Limit
We have previously reported  laser cooling of atoms in optical molasses to temperatures as low as 40 μK; more recently, we have measured the temperature of this three-dimensional gas of Na atoms to be as low as -10 +20 μK. These low temperatures are in strong disagreement with the traditional theory of laser cooling, which predicted a lower limit of 240 μK. Temperatures below the “cooling limit” were surprising and unexpected. They pointed out the inadequacy of the usual theory for explaining a rather simple experiment. The results have great practical interest because it now appears to be relatively easy to obtain temperatures much lower than previously thought possible.
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- P Gould et al., in Laser Spectroscopy VIII,S. Svanberg and W. Persson, Eds. (Springer Verlag, Berlin, 1987) p. 64. and references therein.Google Scholar
- J. Dalibard and C. Cohen-Tannoudji, presented at the Eleventh International Conference on Atomic Physics, Paris, July 1988; presented at this conference; and private communications.Google Scholar
- .S. Chu, presented at the Eleventh International Conference on Atomic Physics, Paris, July 1988.Google Scholar