Southampton Physics Colloquia

Microwave to Optical Signal Transduction using Piezo-Optomechanical Circuits
Dr Krishna Balram University of Bristol 14:30, Friday 24 March 2017
Physics Seminar Room (Building 46/5081)
The detection of weak signals (down to the single quantum level) is pretty standard at optical frequencies, given the high photon energy compared to kT and the ready availability of single photon detectors. The same cannot be said for the RF and microwave frequency ranges (1-10 GHz) wherein the low photon energy gets swamped by thermal noise in detectors, requiring the use of cryogenic amplifiers. A wide variety of applications ranging from radio astronomy, MRI to radar require weak RF signal detection and are limited by the detector sensitivity. An alternative approach is to transduce the signals from the RF to the optical domain and use sensitive optical detection. Such an efficient RF-to-optical transducer becomes paramount if distant systems need to communicate with each other using low loss telecom fibres. Both classical (e.g. radio over fibre systems) and quantum (e.g. linking two superconducting qubits in distant dilution fridges) information processing systems will benefit greatly from the development of an efficient microwave to optical signal transducer.