Optomechanically enhanced precision measurement

Abstract

Cavity optomechanical systems provide excellent platforms for the high-precision measurement of various physical quantities. Here, we investigate the improvement of optomechanical precision measurements based on the tuning of the optomechanical interaction, which can surpass the quantum shot-noise limit without using a squeezed light source. The enhanced performance comes from the optomechanical two-mode squeezing interaction. The approach is based on the tuning of the mechanical susceptibility using optical force, which can be adjusted by controlling the laser frequency and power. For proper blue-detuned laser driving, the mechanical response to the detected signal is greatly enhanced, with improved measurement sensitivity surpassing the shot-noise limit. Moreover, for proper red-detuned laser driving, the working bandwidth can be broadened when the quantum shot noise does not dominate. Our work opens an avenue towards significant improvement to all kinds of optomechanical precision-measurement systems without stringent requirements.