Universal rates for reactive ultracold polar molecules in reduced dimensions

TL;DR

This paper derives universal formulas for elastic and reactive collision rates of ultracold polar molecules in reduced dimensions, providing insights into their stability and cooling strategies.

Contribution

It introduces analytic expressions for collision rates in quasi-2D and quasi-1D ultracold molecules, with calculations for KRb demonstrating practical stability conditions.

Findings

Stability and evaporative cooling are feasible for spin-polarized fermions at moderate parameters.

Bosons and unlike fermions need higher dipole or trapping strengths for stability.

Universal rates depend on dimensional confinement and molecular interactions.

Abstract

Analytic expressions describe universal elastic and reactive rates of quasi-two-dimensional and quasi-one-dimensional collisions of highly reactive ultracold molecules interacting by a van der Waals potential. Exact and approximate calculations for the example species of KRb show that stability and evaporative cooling can be realized for spin-polarized fermions at moderate dipole and trapping strength, whereas bosons or unlike fermions require significantly higher dipole or trapping strengths.