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Influence of a tight isotropic harmonic trap on photoassociation in ultracold homonuclear alkali gases

Sergey Grishkevich·Alejandro Saenz
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Abstract

The influence of a tight isotropic harmonic trap on photoassociation of two ultracold alkali atoms forming a homonuclear diatomic is investigated using realistic atomic interaction potentials. Confinement of the initial atom pair due to the trap leads to a uniform strong enhancement of the photoassociation rate to most, but also to a strongly suppressed rate for some final states. Thus tighter traps do not necessarily enhance the photoassociation rate. A further massive enhancement of the rate is found for strong interatomic interaction potentials. The details of this interaction play a minor role, except for large repulsive interactions for which a sharp window occurs in the photoassociation spectrum as is known from the trap-free case. A comparison with simplified models describing the atomic interaction like the pseudopotential approximation shows that they often provide reasonable estimates for the trap-induced enhancement of the photoassociation rate even if the predicted rates can be completely erroneous.

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Sergey Grishkevich, Alejandro Saenz. 2006-09-19. Influence of a tight isotropic harmonic trap on photoassociation in ultracold homonuclear alkali gases. https://doi.org/10.1103/physreva.76.022704

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