Deborah Jin Award for Outstanding Doctoral Thesis Research in Atomic, Molecular, or Optical Physics Recipient: Millimeter-wave to optical transduction with Rydberg atoms in a hybrid cavity-QED platform

Optical photons are the primary mode of long-distance quantum communication. This means that an efficient optical interface is a necessary ingredient of any quantum processing node of a quantum network and a distributed quantum system. Coherently converting quantum information from the mode of the processor to the mode of the communication channel is a challenge, especially when the processor encodes information in microwave photons which are four orders of magnitude lower in energy than optical photons. Hybrid quantum systems can enable such transduction of quantum information by bridging two different platforms into one with novel capabilities. Here, I will present our quantum interface which couples optical and millimeter-wave photons (100 GHz) using Rydberg atoms. I will describe our novel experimental platform and present our recent results on quantum-limited transduction between millimeter-wave and optical photons. We measure internal conversion efficiency of 58 % with 360 kHz bandwidth and 0.6 added thermal noise, which in the future can be extended to near-unity transduction in both microwave and millimeter-wave regimes. In conclusion, I will describe how the hybrid nature and the access to strong coupling regime in our platform could enable the generation of computationally useful entangled states of light and matter for further development of quantum communication technology.