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arXiv · 1306.3365

Efficient demagnetization cooling of atoms and its limits

Valentin V. Volchkov·Jahn Rührig·Tilman Pfau·Axel Griesmaier
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Abstract

Demagnetization cooling relies on spin-orbit coupling that brings motional and spin degrees of freedom into thermal equilibrium. In the case of a gas, one has the advantage that the spin degree of freedom can be cooled very efficiently using optical pumping. We investigate demagnetization cooling of a chromium gas in a deep optical dipole trap over a large temperature range and reach high densities up to $5\times 10^{19} m^{-3}$. We study the loss mechanism under such extreme conditions and identify excited-state collisions as the main limiting process. We discuss that in some systems demagnetization cooling has a realistic potential of reaching degeneracy by optical cooling only.

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Valentin V. Volchkov, Jahn Rührig, Tilman Pfau, Axel Griesmaier. 2014-05-25. Efficient demagnetization cooling of atoms and its limits. https://doi.org/10.1103/physreva.89.043417

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