Selective enhancement of difference sideband generation in a quadratically coupled optomechanical system with mechanical driving

Abstract

We explore theoretically the generation and selective enhancement of difference sidebands in a quadratically coupled optomechanical system in which the membrane is driven resonantly by an additional coherent mechanical driving field. We show that the generation of frequency components at the difference sideband is directly related to the nonlinear optomechanical interactions under two-phonon resonance condition, while an additional weak coherent mechanical driving field acting on the membrane can considerably establish a selective enhancement of difference sideband generation (DSG). Our analytical solution with experimentally achievable parameters demonstrates that even if the input power of the control field is relatively low DSG can be induced and greatly enhanced when the matching conditions are satisfied. It also indicates that the efficiencies of upper difference sideband generation (UDSG) and lower difference sideband generation (LDSG) can be selectively increased about three orders by properly adjusting the frequency and amplitude of the weakly coherent mechanical driving field. Furthermore, we also show that the matching conditions of UDSG and LDSG are modified by the weakly coherent mechanical driving field. The present investigation may help to achieve the practical application of DSG relevant to nonlinear optics, chip-scale optical communications, and precision measurement.