Vibrational energy transfer in ultracold molecule - molecule collisions

TL;DR

This paper investigates vibrational relaxation mechanisms in ultracold p-H2 + p-H2 collisions, revealing a highly state-selective energy transfer process that conserves internal energy and angular momentum.

Contribution

It provides a rigorous analysis of vibrational energy transfer in ultracold molecules, identifying a specific efficient mechanism involving simultaneous conservation laws.

Findings

Identifies an efficient, state-selective vibrational energy transfer mechanism.

Demonstrates conservation of internal energy and total rotational angular momentum.

Highlights the role of ro-vibrational energy transfer in ultracold molecular collisions.

Abstract

We present a rigorous study of vibrational relaxation in p-H2 + p-H2 collisions at cold and ultracold temperatures and identify an efficient mechanism of ro-vibrational energy transfer. If the colliding molecules are in different rotational and vibrational levels, the internal energy may be transferred between the molecules through an extremely state-selective process involving simultaneous conservation of internal energy and total rotational angular momentum. The same transition in collisions of distinguishable molecules corresponds to the rotational energy transfer from one vibrational state of the colliding molecules to another.