Feshbach resonances of harmonically trapped atoms

TL;DR

This paper develops an analytic model for Feshbach resonances in harmonically trapped atoms, providing new parameterizations and explaining experimental phenomena like resonance shifts and trap-induced molecules.

Contribution

It introduces a novel analytic model using a two-channel approach and a new energy-dependent scattering length parameterization for trapped atoms at Feshbach resonances.

Findings

Validated model against numerical calculations for Li-Rb

Explained experimentally observed resonance shifts

Analyzed bound state admixture and transition probabilities

Abstract

Employing a short-range two-channel description we derive an analytic model of atoms in isotropic and anisotropic harmonic traps at a Feshbach resonance. On this basis we obtain a new parameterization of the energy-dependent scattering length which differs from the one previously employed. We validate the model by comparison to full numerical calculations for Li-Rb and explain quantitatively the experimental observation of a resonance shift and trap-induced molecules in exited bands. Finally, we analyze the bound state admixture and Landau-Zener transition probabilities.