Stochastic resonance in a bistable system driven by cross-correlated noises and an amplitude modulation signal

We explore stochastic resonance effects in a bistable system driven by an amplitude modulation (two-frequencies) signal and cross-correlated additive and multiplicative noises. The analytical expression of the signal-to-noise ratio (SNR) is obtained under the condition of adiabatic approximation. The results manifest: (i) the amplitude modulation deepness and the frequency of the signal affect the SNR intensely; (ii) the cross-correlation of additive and multiplicative noises leads to a novel resonance character. The multi-extrema phenomenon appears in the curve of the SNR as a function of cross-correlation coefficient λ. The SNR versus λ curve not only exhibits the multi-peaks phenomenon, but also the multi-wells phenomenon. This means that we can control the SNR by virtue of controlling λ to obtain a larger SNR under fixed noise intensities.