Stochastic resonance in a new asymmetric bistable system driven by unrelated multiplicative and additive noise

• A new asymmetry bistable system with two asymmetric terms is investigated.
• The expression of mean first-passage time (MFPT) is obtained.
• The analytic expression of signal-to-noise ratio (SNR) is derived.
• The effects of system parameters on the SNR are found.

In this paper, we study the stochastic resonance (SR) in a new asymmetric bistable model driven by unrelated multiplicative and additive noise. Firstly, a new asymmetric bistable model with two asymmetric terms is proposed. Secondly, the mean first-passage time (MFPT) and the signal-to-noise ratio (SNR) as the index of evaluating the model are researched. Applying the two-state theory and the adiabatic approximation theory, the analytical expressions of MFPT and SNR have been obtained for the asymmetric bistable system driven by a periodic signal, unrelated multiplicative and additive noise. Simulation results show that it is easier to generate stochastic resonance to adjust the intensity of additive noise than to adjust multiplicative noise intensity. Adjusting potential asymmetry is easier to obtain stochastic resonance than adjusting noise. In addition, the influence of the noise intensity on MFPT of two different directions is different, which is consistent with the simulation of model with only one asymmetric term.