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arXiv · 0903.2568

Collisional cooling of ultra-cold atom ensembles using Feshbach resonances

L. Mathey·Eite Tiesinga·Paul S. Julienne·Charles W. Clark
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Abstract

We propose a new type of cooling mechanism for ultra-cold fermionic atom ensembles, which capitalizes on the energy dependence of inelastic collisions in the presence of a Feshbach resonance. We first discuss the case of a single magnetic resonance, and find that the final temperature and the cooling rate is limited by the width of the resonance. A concrete example, based on a p-wave resonance of $^{40}$K, is given. We then improve upon this setup by using both a very sharp optical or radio-frequency induced resonance and a very broad magnetic resonance and show that one can improve upon temperatures reached with current technologies.

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L. Mathey, Eite Tiesinga, Paul S. Julienne, Charles W. Clark. 2009-03-14. Collisional cooling of ultra-cold atom ensembles using Feshbach resonances. https://doi.org/10.1103/physreva.80.030702

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