Feshbach resonance in a strictly two-dimensional atomic Bose gas

TL;DR

This paper investigates Feshbach resonances in a two-dimensional Bose gas, analyzing how tunable interactions affect condensate properties and stability, with implications for controlling quantum gases.

Contribution

It introduces a method to tune the interaction strength in a 2D Bose gas and examines the resulting effects on condensate behavior and stability near Feshbach resonances.

Findings

The condensate wave function spreads with increased repulsion.

Stable condensate regimes are identified even near attractive interactions.

A tunable coupling parameter is established for 2D Bose gases.

Abstract

We discuss the atom-atom scattering problem across a Feshbach resonance in a two-dimensional dilute Bose gas at zero temperature, in the limit where the s-wave scattering length exceeds the width of the vertical confinement. We determine a tunable coupling-strength parameter and by controlling it we evaluate how the condensate wave function spreads out with increasing atom-atom repulsions. We also discuss the stability of the condensate in the magnetic-field regime where the coupling has become attractive.