Tuning the dynamic behavior of parametric resonance in a micromechanical oscillator

We describe how to significantly change the dynamic behavior of parametric resonance in a micromechanical oscillator. By varying the voltage amplitude of applied electrical signal, the frequency response of the first order parametric resonance changes dramatically. We attribute this variation to the tuning of effective cubic stiffness of the oscillator, which is a contribution of both structural and electrical cubic stiffness. This phenomenon is well explained by the first-order perturbation analysis of nonlinear Mathieu equation.