Mechanical squeezing induced by Duffing nonlinearity and two driving tones in an optomechanical system

Abstract We propose a scheme to engineer strong steady-state mechanical squeezing via the joint effect between Duffing nonlinearity and two driving tones in an optomechanical system. It is found that the joint effect can achieve strong squeezing exceeding 3 dB when the amplitude ratio of two driving tones is large enough. Moreover, the generated squeezing can be flexibly manipulated by increasing the red-detuned laser power and selecting the amplitude ratio of two driving lasers. The robustness of mechanical squeezing set up by the joint effect to the thermal noise can be improved benefiting from the enhancement of red-detuned laser power. Furthermore, we present that the mechanical squeezing can be directly detected by homodyning the cavity output field under an appropriate phase.