Eur. Phys. J. B (2012) 85: 75
https://doi.org/10.1140/epjb/e2012-21053-0

Regular Article

Stochastic resonance in a bistable system with global delay and two noises

Department of Physics, Yunnan University, Kunming, 650091, P.R. China

^a e-mail: meidch@ynu.edu.cn

Received: 19 December 2011
Received in final form: 12 January 2012
Published online: 27 February 2012

Abstract

The global time delay is introduced into a bistable system driven by two noises and a periodic signal. The signal power amplification factor η is employed to characterise stochastic resonance (SR) of the system. Numerical simulation results indicate the following. (1) For a periodic signal with low frequency (Ω), the typical behaviour of the SR is lowered monotonically by increasing the delay time τ; for moderate Ω, τ enhances the SR behaviour and then weakens it, with a critical value at which the SR is optimum. (2) Multiplicative noise intensity D and additive noise intensity α have different influences on the SR performance, viz D enhances the SR monotonically while α enforces the SR initially and then restrains it; (3) correlation intensity λ between the two noises always weakens the SR behaviour of the system.