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Sympathetic cooling and collisional properties of a Rb-Cs mixture

M. Anderlini·E. Courtade·M. Cristiani·D. Cossart·D. Ciampini·C. Sias·O. Morsch·E. Arimondo
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Abstract

We report on measurements of the collisional properties of a mixture of $^{133}$Cs and $^{87}$Rb atoms in a magnetic trap at $μ\mathrm{K}$ temperatures. By selectively evaporating the Rb atoms using a radio-frequency field, we achieved sympathetic cooling of Cs down to a few $μ\mathrm{K}$. The inter-species collisional cross-section was determined through rethermalization measurements, leading to an estimate of $a_s=595 a_0$ for the s-wave scattering length for Rb in the $|F=2, m_F=2>$ and Cs in the $|F=4, m_F=4>$ magnetic states. We briefly speculate on the prospects for reaching Bose-Einstein condensation of Cs inside a magnetic trap through sympathetic cooling.

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M. Anderlini, E. Courtade, M. Cristiani, D. Cossart, D. Ciampini, C. Sias, O. Morsch, E. Arimondo. 2004-11-23. Sympathetic cooling and collisional properties of a Rb-Cs mixture. https://doi.org/10.1103/physreva.71.061401

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