Reconstruction of Rb-Rb inter-atomic potential from ultracold Bose-gas collision

TL;DR

This paper reconstructs the effective inter-atomic potential for ultracold 87Rb Bose-gas collisions by analyzing scattering phase shifts, revealing a sudden change from repulsive to attractive interactions near a specific energy, which could inform future experiments.

Contribution

It introduces a method to reconstruct inter-atomic potentials from experimental phase shifts and identifies a notable energy-dependent interaction change in 87Rb Bose-gas collisions.

Findings

Interaction strength changes from repulsive to attractive near E=275 mikroK

Potential reconstruction aligns with experimental scattering data

Highlights a shape resonance effect in ultracold collisions

Abstract

Scattering phase shifts obtained from 87Rb Bose-gas collision experiments are used to reconstruct effective potentials resulting, self-consistently, in the same scattering events observed in the experiments at a particular energy. We have found that the interaction strength close to the origin suddenly changes from repulsion to attraction when the collision energy crosses, from below, the l=2 shape resonance position at E = 275 mikroK. This observation may be utilized in outlining future Bose-gas collision experiments.