Resonator-assisted Atom Cooling, Molecule Synthesis and Detection

Due to the rapid development of nanophotonics, microring resonators suspended on a membrane holds promises for a scalable optical circuit with strong light-atom interaction. In this dissertation, I introduce a efficiently-coupled microring circuits for on-chip cavity QED with cold atoms and report my experimental efforts to integrate the optical chip into a ultrahigh-vacuum chamber with a magneto-optical trap for Rb atoms. My attempts to load single atoms into optical tweezers are also discussed.

  Although the loading of atom into optical tweezers above the top surface of resonator remains a challenge in experiment, I propose an alternative of cavity cooling based on cavity QED to facilitate the loading of atom into a two-color evanescent field trap around the waveguide. Assuming that the strong interaction between atoms and resonator modes is realized, I theoretically investigate the synthesis via photoassociation and the direct optical detection of a single ground-state cold molecule, whose corresponding excited-state has multiple decay channels. Similarly to the Purcell effect, the decay in a specific decay channel could be enhanced based on cavity QED, and therefore the synthesis efficiency can approach unity when the interaction between the resonator modes and a single cold molecule becomes stronger. In addition, for a single cold molecule without closed optical transition, the electromagnetically induced transparency is possible to be observed on our nanophotonic platform in the case of strong resonator-molecule coupling.