A Novel Imaging Technique for Optical Tweezer Arrays of CaF Molecules

We report on a novel imaging scheme that offers nearly background-free high-fidelity detection of CaF molecules in optical tweezer traps. Our scheme relies on two distinct electronic transitions, one for laser cooling and one for fluorescent detection, and consequently provides low detection backgrounds. We have quantified the imaging losses and have characterized many of the possible loss channels. We have also identified methods that can mitigate some of these losses. In addition to further improving the detection fidelity, these methods may also help with slowing and MOT loading.