Feshbach resonances in potassium Bose-Bose mixtures

TL;DR

This paper reports the discovery and characterization of 20 new Feshbach resonances in potassium Bose-Bose mixtures, providing valuable data for tuning interactions in ultracold atomic experiments.

Contribution

It identifies and assigns new Feshbach resonances in potassium isotopic mixtures, enhancing control over ultracold Bose-Bose systems.

Findings

20 new Feshbach resonances in 39K-41K mixtures

Characterization of a specific 39K Feshbach resonance

Enlarged experimental possibilities for Bose-Bose mixtures

Abstract

We present a detailed study of the scattering properties of ultracold mixtures of bosonic potassium atoms. We locate 20 previously unobserved Feshbach resonances in isotopic 39K-41K mixtures. These are assigned to s-wave molecular channels by comparison to an asymptotic bound state model and coupled channels calculations. Additional Feshbach resonances are studied in spin mixtures of a single potassium isotope, both in 39K and 41K. In particular, we characterize the parameters of a selected 39K Feshbach resonance by radio-frequency association of Feshbach molecules. Our results could be exploited to refine the model potentials for potassium scattering. Furthermore, these new Feshbach resonances enlarge the range of experiments possible with degenerate Bose-Bose mixtures.