Selective transduction of wine-glass vibration mode using differential optomechanics

This paper demonstrates differential optomechanical transduction which selectively drives and senses the wine-glass vibration mode of a silicon resonator. Two waveguide arms are used for optomechanical sensing at the anti-nodes of the 22 MHz wine-glass mode and utilize a differential photo detector (PD) to measure the vibration. The differential sense scheme enhances the wine-glass signal by 5.4 dB while significantly attenuating the radial “common-mode” vibration at 96.2 MHz by 11 dB.