Nonlinearity characteristic of disk resonator

This work investigated the nonlinear behaviors of the disk resonator. Generally, nonlinearity occurs in resonators with small stiffness, such as cantilever, bridge, etc. However, it was observed that the radial-contour-mode micromechanical disk resonator with large stiffness and high quality factor (Q) also suffers nonlinearity when a large bias voltage is applied. The resonator shows a linear response with a voltage of 10 V in atmosphere and room temperature. However, as it vibrates in vacuum or at low temperature (below 110 K), nonlinearity occurs even with a bias voltage of 6 V. This nonlinear effect is closely related to the change of quality factor, and a small driving force is suggested to make sure the device works in linear regime when operating the disk resonator at low temperature or in vacuum.