Fig. 4. Room temperature mechanical spectroscopy.

a Measured mechanical noise power spectrum for one device each for θ = 0°, 15°, 30°, and 45°. b Mechanical frequency distribution of a group of five devices for each θ. Error bars indicate one standard deviation (error bars smaller than the symbol are not shown). Dashed lines are the simulated mechanical frequencies. c Unit-cell optomechanical coupling. The dashed lines correspond to simulated coupling for w = 28 nm (top) and 40 nm (bottom). d Total quality factor of the mechanical modes. The dashed lines are the estimated bound and mean from the simulation of a 1 × 4 super-cell with disorders.