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Time dependence of laser cooling in optical lattices

Claude M. Dion·Peder Sjolund·Stefan J. H. Petra·Svante Jonsell·Anders Kastberg
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Abstract

We study the dynamics of the cooling of a gas of caesium atoms in an optical lattice, both experimentally and with 1D full-quantum Monte Carlo simulations. We find that, contrary to the standard interpretation of the Sisyphus model, the cooling process does not work by a continuous decrease of the average kinetic energy of the atoms in the lattice. Instead, we show that the momentum of the atoms follows a bimodal distribution, the atoms being gradually transferred from a hot to a cold mode. We suggest that the cooling mechanism should be depicted in terms of a rate model, describing the transfer between the two modes along with the processes occurring within each mode.

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Claude M. Dion, Peder Sjolund, Stefan J. H. Petra, Svante Jonsell, Anders Kastberg. 2005-09-05. Time dependence of laser cooling in optical lattices. https://doi.org/10.1209/epl%2Fi2005-10244-6

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