Using an Optical Conveyor for Light-Matter Interaction Experiments

Abstract

In this work, we cool Rubidium atoms to the Doppler limit. After atoms were cooled, we use two purely optical traps, an Optical Dipole Trap (ODT) and a standing wave trap (optical conveyor) to transport them. We have optimized the performance of the standing wave trap and succeeded to slowly transport 105 traps and cools atoms to the surface of a nanophotonic sample located 5 mm from the loading point. We calibrated the required optical power during absorption imaging for the accurate and reproducible calculation of the number of trapped atoms. A 200 nm thin free-standing Silicon-Nitride slab waveguide was used to probe interactions between atoms and resonant light in the guided mode. The propagating mode has an evanescent tail that extends further than the physical dimensions of the waveguide. Bringing atoms to the resonant field can trigger interactions between light and atoms. We succeeded in coupling light in and out of the waveguide and built a dedicated imaging section for the transmission. Last, we performed a reference experiment to determine the response of the optical setup, without the presence of atoms at the proximity of the slab waveguide.