Vibrational quenching and reactive processes of weakly bound molecular ion-atom collisions at cold temperatures

TL;DR

This study investigates vibrational quenching and chemical processes of BaRb+ molecular ions in ultracold Rb gases using quasi-classical trajectory simulations, revealing efficient energy transfer and large quenching cross sections.

Contribution

It provides the first detailed analysis of vibrational quenching in BaRb+ ions at cold temperatures, demonstrating the applicability of the Langevin capture model.

Findings

Vibrational quenching cross sections are large and follow the Langevin model.

Energy transfer between translational and internal degrees is highly efficient.

Results inform understanding of molecular ion relaxation in ultracold gases.

Abstract

We present a study of vibrational quenching and chemical processes of molecular ions immersed in an ultracold atomic gas by means of the quasi-classical trajectory (QCT) method. In particular, BaRb$^+(v)$ + Rb collisions are studied at cold temperatures revealing a highly efficient energy transfer between the translational degrees of freedom and internal degrees of the molecular ion. Thus leading to a large vibrational quenching cross section which follows the Langevin capture model prediction. These results play a key role on the understanding of relaxation phenomena of cold molecular ions in ultracold gases as well as in the fate of the molecules emerging trough ion-neutral-neutral three-body recombination in an cold and dense environment.