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arXiv · 2207.02092

Triatomic Photoassociation in an Ultracold Atom-Molecule Collision

Ahmed A. Elkamshishy·Chris H. Greene
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Abstract

Ultracold collisions of neutral atoms and molecules have been of great interest since experimental advances enabled the cooling and trapping of such species. This study is a theoretical investigation of a low-energy collision between an alkali atom and a diatomic molecule, accompanied by absorption of a photon from an external electromagnetic field. The long-range interaction between the two species is treated, including the atomic spin-orbit interaction. The long-range potential energy curves for the triatomic complex are calculated in realistic detail, while the short-range behavior is mimicked by applying different boundary conditions at the van der Waals length. The photoassociation (PA) rate of an atom colliding with a dimer is calculated for different alkali atoms, namely Na and Cs. The model developed in this study is also tested against known results for the formation rate of the Cs$_3$ complex via PA, namely to compare with the work done by Rios et al., PRL 115, 073201 (2015), and the results are in generally good agreement.

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Ahmed A. Elkamshishy, Chris H. Greene. 2022-07-05. Triatomic Photoassociation in an Ultracold Atom-Molecule Collision. https://doi.org/10.1021/acs.jpca.2c04727

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