Microresonators based on 1:2 internal resonance

A nonlinear autoparametric resonance based microresonator concept is explored in this study. The concept is illustrated by modelling an electrostatically actuated T-beam structure, with the first two modes of the structure in 1:2 internal resonance. The response of the system to primary resonance of the first and second mode is presented. When the second mode is resonantly actuated, the second mode in turn excites the first mode due to 1:2 internal resonance and the nonlinear coupling between the two modes. The structure therefore oscillates in first mode with half the frequency of excitation voltage. This is a unique feature of this microresonator, and as a result of this feature, the resonator can serve as a filter as well as a mixer in RF MEMS devices. When the first mode is excited, the structure oscillates in both the first and the second mode and thus has an output signal with frequency twice the input signal. The response also showed Hopf-bifurcations for higher actuation voltages.