A high-cooperativity, silicon nitride transducer for room temperature quantum optomechanics

At room temperature, the thermal noise of a mechanical resonator typically dominates the quantum backaction (QBA) of its position measurement and prohibits entering the quantum regime of optomechanics. Milestones such as cooling to the ground state and generation of squeezed light have been demonstrated, but so far typically at cryogenic temperature. Room temperature operation would allow these effects to be observed in simplified experimental setups and enable new applications.
We present a nano-optomechanical transducer using high stress silicon nitride that features a one-dimensional optical cavity (Q>10^5) integrated with a high aspect ratio nanobeam resonator(Q>10^6). Our approach allows individual optimization of the optical and the mechanical resonator while maintaining a high optomechanical coupling rate. This system provides a platform for observation of room temperature quantum backaction on macroscopic mechanical resonators owing to its high single photon cooperativity (C0 = 23).