Graphene optomechanics realized at microwave frequencies

Cavity optomechanics has served as a platform for studying the interaction between light and micromechanical motion via radiation pressure. Here we observe such phenomena with a graphene mechanical resonator coupled to an electromagnetic mode. We measure thermal motion and back-action cooling in a bilayer graphene resonator coupled to a microwave on-chip cavity. We detect the lowest flexural mode at 24 MHz down to 50 mK, corresponding to roughly mechanical 40 quanta, representing nearly three orders of magnitude lower phonon occupation than recorded to date with graphene resonators.