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arXiv · 0908.2071

Broad Feshbach resonance in the 6Li-40K mixture

T. G. Tiecke·M. R. Goosen·A. Ludewig·S. D. Gensemer·S. Kraft·S. J. J. M. F. Kokkelmans·J. T. M. Walraven
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Abstract

We study the widths of interspecies Feshbach resonances in a mixture of the fermionic quantum gases 6Li and 40K. We develop a model to calculate the width and position of all available Feshbach resonances for a system. Using the model we select the optimal resonance to study the 6Li/40K mixture. Experimentally, we obtain the asymmetric Fano lineshape of the interspecies elastic cross section by measuring the distillation rate of 6Li atoms from a potassium-rich 6Li/40K mixture as a function of magnetic field. This provides us with the first experimental determination of the width of a resonance in this mixture, Delta B=1.5(5) G. Our results offer good perspectives for the observation of universal crossover physics using this mass-imbalanced fermionic mixture.

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T. G. Tiecke, M. R. Goosen, A. Ludewig, S. D. Gensemer, S. Kraft, S. J. J. M. F. Kokkelmans, J. T. M. Walraven. 2010-02-11. Broad Feshbach resonance in the 6Li-40K mixture. https://doi.org/10.1103/physrevlett.104.053202

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