Coupled Piezoelectric and Optomechanical Resonators for RF-to-optical Frequency Conversion*

The development of quantum computing technologies currently faces interconnectivity barriers. A leading platform for quantum processors uses superconducting microwave or radio-frequency (RF) circuits encased inside dilution refrigerators at millikelvin temperatures. Long-range communication is thus a major challenge due to loss of signal outside cryogenic environment. Recently, RF-to-optical photon converters have attracted significant interest for their use in linking RF signals to an optical signal that can propagate in high-speed low-loss optical fiber networks. We propose an on-chip nanoscale converter that connects RF signals to mechanical degrees of freedom using a piezoelectric resonator and then bridges to the optical domain using an optomechanical resonator. This effective electro-mechano-optical modulator is built on a GaAs material platform which exhibits strong photoelastic effect for optomechanical coupling. We demonstrate new device designs that compensate for the inherently low piezoelectric effect in GaAs and progress in the fabrication of an integrated piezo-optomechanical device.