47 / 2016-10-10 16:44:39

Mass sensor based on split-nanobeam optomechanical oscillator

Optomechanics,Photonic crystals,Acousto-optical devices,Sensors

Mass sensing based on monitoring the frequency shifts induced by added mass in oscillators is a well-known and widely used technique. The optomechanical crystal cavity has strong interaction between optical mode and mechanical mode. Radiation pressure driven optomechanical crystal cavity are excellent candidates for mass detection due to their simplicity, sensitivity and all optical operation. In an optomechanical crystal cavity, a high quality factor optical mode simultaneously serves as an efficient actuator and a sensitive probe for precise monitoring the mechanical frequency change of the cavity structure. Here, a split-nanobeam optomechanical crystal cavity is proposed, the sensing resolution as small as 0.33ag (1ag=10^-21kg) and the frequency shift is more than 30MHz. This is important and promising for achieve ultimate-precision mass sensing including proteins and other molecules.