Theory of controlling stochastic resonance

Abstract
The concept of controlling stochastic resonance has been recently introduced [L. Gammaitoni et al., Phys. Rev. Lett. 82, 4574 (1999)] to enhance or suppress the spectral response to threshold-crossing events triggered by a time-periodic signal in background noise. Here, we develop a general theoretical framework, based on a rate equation approach. This generic two-state theory captures the essential features observed in our experiments and numerical simulations.