Feshbach resonances in the 6Li-40K Fermi-Fermi mixture: Elastic versus inelastic interactions

TL;DR

This paper provides a comprehensive theoretical and experimental analysis of Feshbach resonances in the 6Li-40K mixture, focusing on elastic and inelastic scattering, and identifies optimal resonances for interaction control.

Contribution

It offers the first detailed study of inelastic scattering in this system and compares theoretical predictions with experimental data for a key resonance near 155 G.

Findings

Excellent agreement between theory and experiment for the 155 G resonance

Characterization of the molecular state's lifetime against dissociation

Survey of multiple resonances with detailed elastic and inelastic properties

Abstract

We present a detailed theoretical and experimental study of Feshbach resonances in the 6Li-40K mixture. Particular attention is given to the inelastic scattering properties, which have not been considered before. As an important example, we thoroughly investigate both elastic and inelastic scattering properties of a resonance that occurs near 155 G. Our theoretical predictions based on a coupled channels calculation are found in excellent agreement with the experimental results. We also present theoretical results on the molecular state that underlies the 155G resonance, in particular concerning its lifetime against spontaneous dissociation. We then present a survey of resonances in the system, fully characterizing the corresponding elastic and inelastic scattering properties. This provides the essential information to identify optimum resonances for applications relying on interaction control in this Fermi-Fermi mixture.