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Collisional properties of ultracold K-Rb mixtures

G. Ferrari·M. Inguscio·W. Jastrzebski·G. Modugno·G. Roati·A. Simoni
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Abstract

We determine the inter-species s-wave triplet scattering length a3 for all K-Rb isotopic mixtures by measuring the cross-section for collisions between 41K and 87Rb in different temperature regimes. The positive value a3=+163(+57,-12)a0 ensures the stability of binary 41K-87Rb Bose-Einstein condensates. For the fermion-boson mixture 40K-87Rb we obtain a large and negative scattering length which implies an efficient sympathetic cooling of the fermionic species down to the degenerate regime.

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G. Ferrari, M. Inguscio, W. Jastrzebski, G. Modugno, G. Roati, A. Simoni. 2003-04-17. Collisional properties of ultracold K-Rb mixtures. https://doi.org/10.1103/physrevlett.89.053202

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