Electric field induced saturation effects in photoassociation of a pair of heteronuclear atoms

TL;DR

This paper theoretically investigates how a static electric field can induce saturation effects in the photoassociation process of heteronuclear atom pairs, revealing resonances and rate modifications relevant for polar molecule formation.

Contribution

It introduces a detailed theoretical analysis of electric field-induced saturation effects on heteronuclear photoassociation, including anisotropic resonances and rate splitting phenomena.

Findings

Electric fields cause anisotropic resonances affecting scattering wave-functions.

Photoassociation rates exhibit splitting and dips near resonant electric fields.

Electric fields can potentially enhance ground state polar molecule formation.

Abstract

We theoretically study saturation effects induced by an external static electric field on photoassociation (PA) of a heteronuclear atom pair. A static electric field influences scattering wave-function of two heteronuclear atoms as described in [D. Chakraborty, J. Hazra and B. Deb, J. Phys. B. {\bf 44} 095201 (2011)]. For certain values of electric field strengths there exist anisotropic resonances in ground state scattering leading to a large modification of scattering wave-function at short and intermediate separations where photoassociative Franck-Condon overlap is significant. Photoassociation rate as a function of collision energy shows a splitting near resonant electric field in the mili Kelvin energy regime. This splitting with a prominent dip occurs due to resonant enhancement of free-bound stimulated linewidth leading to saturation in free-bound transitions. We study electric field induced saturation effects on both one- and two-colour PA. Our results suggest that a static electric field may influence the formation of ground state polar molecules in two-colour PA.