Magnetic control of ultra-cold $^6$Li and $^{174}$Yb($^3P_2$) atom mixtures with Feshbach resonances

TL;DR

This paper theoretically investigates the potential to create magnetically-tunable Feshbach molecules from collisions between fermionic $^6$Li and bosonic $^{174}$Yb($^3P_2$) atoms, highlighting the role of anisotropic interactions and resonance broadening.

Contribution

It presents the first-principle coupled-channel calculations revealing broad Feshbach resonances in Li-Yb collisions, with optimized potentials fitting experimental data and analyzing anisotropic effects.

Findings

Existence of broad Feshbach resonances due to anisotropic interactions

Identification of dominant resonance quantum numbers

Role of collisional anisotropy in resonance broadening

Abstract

We theoretically evaluate the feasibility to form magnetically-tunable Feshbach molecules in collisions between fermionic $^6$Li atoms and bosonic metastable $^{174}$Yb($^3$P$_2$) atoms. In contrast to the well-studied alkali-metal atom collisions, collisions with meta-stable atoms are highly anisotropic. Our first-principle coupled-channel calculation of these collisions reveals the existence of broad Feshbach resonances due to the combined effect of anisotropic-molecular and atomic-hyperfine interactions. In order to fit our predictions to the specific positions of experimentally-observed broad resonance structures \cite{Deep2015} we optimized the shape of the short-range potentials by direct least-square fitting. This allowed us to identify the dominant resonance by its leading angular momentum quantum numbers and describe the role of collisional anisotropy in the creation and broadening of this and other resonances.