Rotational state resolved photodissociation spectroscopy of translationally and vibrationally cold MgH⁺ions: toward rotational cooling of molecular ions

Abstract

<p style="text-align: left">The first steps toward the implementation of a simple scheme for rotational cooling of MgH⁺ ions based on rotational state optical pumping is considered. The various aspects of such an experiment are described in detail, and the rotational state-selective dissociation spectra of translationally and vibrationally cold MgH⁺ ions are presented, with and without the optical pumping laser being present. While rotational cooling is as yet not evident, first results showed evidence of a change in the rotational distribution in the presence of the optical pumping laser.