A High Cooperativity Silicon Nitride Optomechanical Transducer

Mechanical resonators are a canonical system for the exploration of quantum measurements. Milestones such as cooling to the ground state and generation of squeezed light have been demonstrated, but so far typically at cryogenic temperatures [1] , [2] . Room temperature operation would allow these effects to be observed in simplified experimental setups and potentially enable new applications inside and outside the laboratory. However, at room temperature, the thermal noise of a mechanical resonator usually dominates the quantum backaction of light and prohibits entering the quantum regime of optomechanics. Therefore, reduced mechanical dissipation is required to isolate the system from the environment. We present a platform that solves this problem: a nano-optomechanical transducer using high stress Si 3 N 4 , which features a one-dimensional Fabry-Pérot optical cavity integrated with a high aspect ratio nanobeam mechanical resonator reaching single photon optomechanical cooperativity exceeding 10 3 .