Optomechanical devices. a) Optical micrograph of an on-chip torsional optomechanical device taken with the imaging system used to observe the optomechanical chamber. The green indicates etched regions, while the remaining device layer is shown in pink. The large etched region provides access for the dimple to couple to the microdisk. On the right are SEM images of b) a torsional mechanical device and c) a microcantilever, both of which are side-coupled to a microdisk WGM resonator. Note that the cantilever follows the curvature of the disk to enhance optomechanical coupling. All scale bars are 5 μm.