Experimental and theoretical study of the noise-induced gain degradation in vibrational resonance

We present the results of theoretical and experimental investigations of the effect of additive noise on vibrational resonance in a bistable system driven by two periodic forces with very different frequencies. The phenomenon shows up as a parametric amplification of the low-frequency signal depending on the amplitude of high-frequency modulation. A scaling law for noise-induced decreasing of the gain factor, found theoretically, is compared with the experimental results obtained in a bistable vertical cavity surface emitting laser.