Effects of colored noise on stochastic resonance in a bistable system subject to multiplicative and additive noise - art. no. 031107

The effects of colored noise on stochastic resonance (SR) in a bistable sys tem driven by multiplicative colored noise and additive white noise and a p eriodic signal are studied by using the unified colored noise approximation and the theory of signal-to-noise ratio (SNR) in the adiabatic limit. In t he case of no correlations between noises, there is an optimal noise intens ities ratio R at which SNR is a maximum that identifies the characteristics of the SR when the correlation time tau of the multiplicative colored nois e is small. However, when tau is increased, a second optimal value of R app ears, and two peaks appear in the SNR simultaneously. In the case of correl ations between noises, the SNR is not only dependent on the correlation tim e tau, but also on the intensity of correlations between noises. Moreover, the double peak phenomenon can also appear as tau is increased in certain s ituations.