A hybrid system for interfacing mm-wave and optical photons: Part 2

In the second of the two talks, I will describe integrating a high power ultra-violet (UV) 297 nm laser into our hybrid experimental setup. The UV laser closes the loop for interconversion between the mm-wave and optical modes. It also enables fast coherent excitation to the rydberg state, where the high cooperativity mm-wave cavity can be used to generate spin-squeezing. We observe that the UV laser strongly affects the finesse and the effective length of the optical cavity, and I will describe how we overcome these effects. I will also describe how the optical cavity can be used to efficiently detect depletion of the atoms from ground state due to the UV laser, thus enabling spectroscopy of the direct rydberg transition as well as observation of rabi-flopping in a cloud of atoms. I will also give an update on quantum transduction in this system.