Confinement-induced resonances for a two-component ultracold atom gas in arbitrary quasi-one-dimensional traps

TL;DR

This paper develops a comprehensive theoretical framework to analyze two-particle scattering in ultracold atom gases confined in arbitrary quasi-one-dimensional traps, revealing confinement-induced resonances for different atom species.

Contribution

It introduces a general solution for two-particle scattering in arbitrary traps with non-factorizable center-of-mass and relative motions, including bound states and resonances.

Findings

Resonances in 1D scattering length due to confinement

Application to two-species mixtures and non-parabolic traps

General formalism for arbitrary quasi-1D potentials

Abstract

We solve the two-particle s-wave scattering problem for ultracold atom gases confined in arbitrary quasi-one-dimensional trapping potentials, allowing for two different atom species. As a consequence, the center-of-mass and relative degrees of freedom do not factorize. We derive bound-state solutions and obtain the general scattering solution, which exhibits several resonances in the 1D scattering length induced by the confinement. We apply our formalism to two experimentally relevant cases: (i) interspecies scattering in a two-species mixture, and (ii) the two-body problem for a single species in a non-parabolic trap.