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Physical Review Letters

Reabsorption of Light by Trapped Atoms

Yvan Castin, J. I. Cirac, Maciej Lewenstein

Published Jun 15, 1998• 88 citations
Publisher

Abstract

We investigate the effect of reabsorption of photons in laser cooling of trapped atoms, in view of a possible achievement of Bose-Einstein condensation by purely optical means. Reabsorption can be strongly suppressed by using strongly deformed traps and by reducing the fluorescence rate to a value smaller than the trap frequencies.
DOI
10.1103/physrevlett.80.5305

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The laser cooling and trapping of 87Rb{ }^{87} \mathbf{R b}87Rb atoms in pure-optical two frequency trap is studied in details. The parameter ranges in which optimal laser cooling is achieved were studied for the first time. The atoms can be simultaneously cooled and trapped by bichromatic laser field that opens up possibility to realize principally new type of pure optical trap. The depth of our trap is hundreds of spontaneous relaxation frequencies which corresponds to the depth of the magneto-optical traps used in the experiments.