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arXiv · 0803.0651

Accurate near-threshold model for ultracold KRb dimers from interisotope Feshbach spectroscopy

A. Simoni·M. Zaccanti·C. D'Errico·M. Fattori·G. Roati·M. Inguscio·G. Modugno
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Abstract

We investigate magnetic Feshbach resonances in two different ultracold K-Rb mixtures. Information on the K(39)-Rb(87) isotopic pair is combined with novel and pre-existing observations of resonance patterns for K(40)-Rb(87). Interisotope resonance spectroscopy improves significantly our near-threshold model for scattering and bound-state calculations. Our analysis determines the number of bound states in singlet/triplet potentials and establishes precisely near threshold parameters for all K-Rb pairs of interest for experiments with both atoms and molecules. In addition, the model verifies the validity of the Born-Oppenheimer approximation at the present level of accuracy.

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A. Simoni, M. Zaccanti, C. D'Errico, M. Fattori, G. Roati, M. Inguscio, G. Modugno. 2008-03-05. Accurate near-threshold model for ultracold KRb dimers from interisotope Feshbach spectroscopy. https://doi.org/10.1103/physreva.77.052705

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