A new method for resonant sensing based on noise in nonlinear MEMS

This paper investigates a new method for tracking parameters at which dynamic bifurcations occur in MEMS. Taking advantage of the changes in phase and amplitude which precede a critical pitchfork bifurcation, feedback control of the root mean square of the amplitude can be utilized to stabilize a device on the "edge" of instability. This can then be used as a method of tracking parameter changes in the device, e.g., as a mass sensor. Sensitivity to these device parameters is explored and initial results show sensitivity of 50 ppm for vibration amplitudes near the noise floor.