Three-body problem in heteronuclear mixtures with resonant interspecies interaction

TL;DR

This paper investigates the three-body problem in heteronuclear mixtures with resonant interspecies interactions using effective field theory, providing analytical and numerical solutions for key scattering properties relevant to experiments.

Contribution

It introduces a zero-range approximation approach to solve the three-body problem, deriving integral equations and analytical solutions for atom-dimer interactions in heteronuclear mixtures.

Findings

Calculated atom-dimer scattering lengths and relaxation rates.

Identified positions of recombination loss peaks depending on mass ratio.

Provided insights applicable to Bose-Bose and Bose-Fermi mixture experiments.

Abstract

We use the zero-range approximation to study a system of two identical bosons interacting resonantly with a third particle. The method is derived from effective field theory. It reduces the three-body problem to an integral equation which we then solve numerically. We also develop an alternative approach which gives analytic solutions of the integral equation in coordinate representation in the limit of vanishing total energy. The atom-dimer scattering length, the rates of atom-dimer relaxation and three-body recombination to shallow and to deep molecular states are calculated either analytically or numerically with a well controlled accuracy for various energies as functions of the mass ratio, scattering length, and three-body parameter. We discuss in detail the relative positions of the recombination loss peaks, which in the universal limit depend only on the mass ratio. Our results have implications for ongoing and future experiments on Bose-Bose and Bose-Fermi atomic mixtures.