BaF molecules in neon ice: trapping, spectroscopy and optical control of electron spins

TL;DR

This paper demonstrates trapping BaF molecules in neon ice, using laser spectroscopy to control and measure electron spins, enabling new avenues for precision physics experiments beyond the standard model.

Contribution

It introduces a novel method of trapping and optically controlling heavy polar molecules in a neon ice matrix for quantum measurements.

Findings

Neon lattice minimally perturbs optical transitions

Laser polarization of electron spins in trapped molecules

Detection of spin flips and hyperfine transitions

Abstract

We have trapped BaF molecules in neon ice, and used laser-induced fluorescence spectroscopy to map out optical transitions in the trapped molecules. Our measurements show that the neon lattice does not significantly perturb certain optical transitions in the trapped molecules. We used one of these transitions to polarize the electron spins, detect spin flips and measure hyperfine transitions in the trapped molecules, entirely using lasers. This demonstration with heavy polar molecules opens up new opportunities for precision measurements of beyond-standard-model physics.