Photonic MEMS vibrating at X-band rates (11 GHz)

We report on an opto-mechanical resonator with vibration excited by compressive radiation pressure via Stimulated Brillouin Scattering [SBS]. We experimentally excite an 11 GHz mechanical whispering gallery mode [WGM] from an optical WGM. The mechanical vibration is detected via the red Doppler shifted light it scatters. We numerically solve the stress-strain equation to calculate the circumferentially circulating mechanical WGM and reveal mechanical WGMs with a variety of transverse shapes. The rate of vibration can be high irrespective of the fabrication tolerances as the driving forces are applied on an optical wavelength scale.