Dispersion management using betatron resonances in an ultracold-atom storage ring

TL;DR

This paper demonstrates how betatron resonances in an ultracold-atom storage ring can significantly reduce longitudinal dispersion of atomic beams, enhancing atom interferometry performance.

Contribution

It reports the first direct observation of betatron resonances in an ultracold-atom storage ring and shows how to control these resonances to improve beam coherence.

Findings

Betatron resonances cause near-elimination of longitudinal dispersion.

Resonant velocities and resonance strength can be tuned via storage ring modifications.

Enhanced atom interferometry potential due to dispersion reduction.

Abstract

Specific velocities of particles circulating in a storage ring can lead to betatron resonances at which static perturbations of the particles' orbit yield large transverse (betatron) oscillations. We have observed betatron resonances in an ultracold-atom storage ring by direct observation of betatron motion. These resonances caused a near-elimination of the longitudinal dispersion of atomic beams propagating at resonant velocities, an effect which can improve the performance of atom interferometric devices. Both the resonant velocities and the strength of the resonances were varied by deliberate modifications to the storage ring.