Confinement-Induced Resonances in Low-Dimensional Quantum Systems

TL;DR

This paper reports the experimental observation of confinement-induced resonances in low-dimensional quantum gases, revealing how confinement geometry and anisotropy influence scattering properties and resonance behavior.

Contribution

It provides the first experimental evidence of confinement-induced resonances in 1D and 2D quantum gases with tunable interactions, including effects of anisotropy.

Findings

Resonances occur when the scattering length matches the confinement length scale.

Anisotropy causes splitting and emergence of additional resonances.

One resonance persists in the 2D limit.

Abstract

We report on the observation of confinement-induced resonances in strongly interacting quantum-gas systems with tunable interactions for one- and two-dimensional geometry. Atom-atom scattering is substantially modified when the s-wave scattering length approaches the length scale associated with the tight transversal confinement, leading to characteristic loss and heating signatures. Upon introducing an anisotropy for the transversal confinement we observe a splitting of the confinement-induced resonance. With increasing anisotropy additional resonances appear. In the limit of a two-dimensional system we find that one resonance persists.