Activation barrier scaling for fluctuation induced switching in driven non-linear micromechanical oscillators

Abstract

We explore fluctuation induced switching in an underdamped micromechanical torsional oscillator driven far from equilibrium. Under a sufficiently strong periodic driving field, the oscillator possesses multiple stable dynamical states. Depending on whether the device is resonantly or parametrically driven, two different types of bifurcation occur. In the presence of noise, the oscillator is induced to switch from one dynamical state into the other. Near the bifurcation points, the activation barrier exhibits a power law dependence on the frequency detuning. The critical exponents are measured to be different for the two types of bifurcation. Both values are in agreement with theoretical predictions. Such scaling of the activation barrier close to the bifurcation point is expected to occur in all systems that are driven away from equilibrium.

Switching dynamics and linear response spectra of a driven one-dimensional nonlinear lattice containing an intrinsic localized mode

“…Because the Duffing resonator is the simplest nonlinear oscillator with these phenomena, this model system has been used for a variety of theoretical studies [37][38][39][40][41], for developing new ideas [31,42], and for applications [43][44][45]. A stochastic resonance when the Duffing resonator is at a kinetic phase transition, where the system is simultaneously in 50% high and 50% low amplitude states, is one example [46,47]. Another example is a bifurcation amplifier, which uses the sudden change at the bifurcation to amplify a signal [43].…”