The prospects of forming ultracold molecules in $^2\Sigma$ states by magnetoassociation of alkali-metal atoms with Yb

TL;DR

This paper investigates the potential for creating ultracold diatomic molecules with electric and magnetic dipole moments via magnetoassociation of alkali-metal atoms with ytterbium, focusing on Feshbach resonances and their dependencies.

Contribution

It provides a systematic survey of Feshbach resonances in alkali-metal and Yb systems, highlighting how resonance widths depend on various atomic and magnetic parameters.

Findings

Resonance widths can exceed 100 mG in favorable cases.

Resonance widths depend strongly on background scattering length and hyperfine coupling.

Isotope selection of Yb influences the resonance properties.

Abstract

We explore the feasibility of producing ultracold diatomic molecules with nonzero electric and magnetic dipole moments by magnetically associating two atoms, one with zero electron spin and one with nonzero spin. Feshbach resonances arise through the dependence of the hyperfine coupling on internuclear distance. We survey the Feshbach resonances in diatomic systems combining the nine stable alkali-metal isotopes with those of Yb, focussing on the illustrative examples of RbYb and CsYb. We show that the resonance widths may expressed as a product of physically comprehensible terms in the framework of Fermi's Golden Rule. The resonance widths depend strongly on the background scattering length, which may be adjusted by selecting the Yb isotope, and on the hyperfine coupling constant and the magnetic field. In favorable cases the resonances may be over 100 mG wide.