Negative Nonlinear Dissipation in Microelectromechanical Beams

In this work we present measurements of drive-induced negative nonlinear dissipation present in doubly clamped microbeams fabricated in a hermetically sealed package. We characterize the amplitude-frequency nonlinearity and nonlinear dissipation present in this system under direct drive. The negative nature of the nonlinear dissipation is observed when measuring either the directly- or parametrically-actuated response. By comparing to the free ringdown response, we confirm that the nonlinear dissipation is induced by driving the resonator. Drive-induced nonlinear damping is an important consideration for resonant sensors and oscillators operated at large amplitudes.