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arXiv · 1208.4569

Feshbach spectroscopy of an ultracold mixture of $^{85}$Rb and $^{133}$Cs

Hung-Wen Cho·Daniel J. McCarron·Michael P. Koppinger·Daniel L. Jenkin·Kirsteen L. Butler·Paul S. Julienne·Caroline L. Blackley·C. Ruth Le Sueur·Jeremy M. Hutson·Simon L. Cornish
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Abstract

We report the observation of interspecies Feshbach resonances in an optically trapped mixture of $^{85}$Rb and $^{133}$Cs. We measure 14 interspecies features in the lowest spin channels for a magnetic field range from 0 to 700 G and show that they are in good agreement with coupled-channel calculations. The interspecies background scattering length is close to zero over a large range of magnetic fields, permitting the sensitive detection of Feshbach resonances through interspecies thermalisation. Our results confirm the quality of the Rb-Cs potential curves and offer promising starting points for the production of ultracold polar molecules.

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Hung-Wen Cho, Daniel J. McCarron, Michael P. Koppinger, Daniel L. Jenkin, Kirsteen L. Butler, Paul S. Julienne, Caroline L. Blackley, C. Ruth Le Sueur, Jeremy M. Hutson, Simon L. Cornish. 2012-08-22. Feshbach spectroscopy of an ultracold mixture of $^{85}$Rb and $^{133}$Cs. https://doi.org/10.1103/physreva.87.010703

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