Theory of long-range ultracold atom-molecule photoassociation

TL;DR

This paper presents a theoretical framework for photoassociating ultracold atoms and molecules to form excited triatomic molecules, expanding ultracold chemistry beyond diatomic species with predicted rates comparable to existing atom-atom photoassociation.

Contribution

It introduces a novel theoretical model for atom-molecule photoassociation to create ultracold triatomic molecules, including rate predictions and an experimental observation proposal.

Findings

Predicted formation rate of excited Cs3 molecules is comparable to atom-atom photoassociation rates.

Developed a quantum dynamic model for long-range atom-molecule interactions.

Proposed experimental methods using optical lattices and photoassociation spectroscopy.

Abstract

The creation of ultracold molecules is currently limited to diatomic species. In this letter we present a theoretical description of the photoassociation of ultracold atoms and molecules to create ultracold excited triatomic molecules, thus being a novel example of light-assisted ultracold chemical reaction. The calculation of the photoassociation rate of ultracold Cs atoms with ultracold Cs$_2$ molecules in their rovibrational ground state is reported, based on the solution of the quantum dynamics involving the atom-molecule long-range interactions, and assuming a model potential for the short-range physics. The rate for the formation of excited Cs$_3$ molecules is predicted to be comparable with currently observed atom-atom photoassociation rates. We formulate an experimental proposal to observe this process relying on the available techniques of optical lattices and standard photoassociation spectroscopy.