Universality Constraints on Three-Body Recombination for Cold Atoms: from 4He to 133Cs

TL;DR

This paper investigates universal behaviors in three-body recombination rates for cold atoms with large scattering lengths, using helium-4 data to predict rates for cesium-133 and comparing with experiments.

Contribution

It introduces a method to use helium-4 data to constrain universal functions, enabling predictions of recombination rates for other atoms like cesium-133.

Findings

Universal functions depend on a single scaling variable.

Helium-4 data constrains these functions effectively.

Predicted rates for cesium-133 agree with experimental results.

Abstract

For atoms with large scattering length, the dependence of the 3-body recombination rate on the collision energy is determined by the scattering length and the Efimov 3-body parameters and can be expressed in terms of universal functions of a single scaling variable. We use published results on the 3-body recombination rate for 4He atoms to constrain the universal functions. We then use those universal functions to calculate the 3-body recombination rate for other atoms with large scattering length at nonzero temperature. The constraints from the 4He results are strong if the scattering length is near the minimum of the 3-body recombination rate at threshold. We apply our results to 133Cs atoms with a large positive scattering length, and compare them with experimental results from the Innsbruck group.