Effects of correlation time between noises on the noise enhanced stability phenomenon in an asymmetric bistable system

The effects of the correlation time τ between noises on the noise-enhanced stability(NES) phenomenon in an asymmetric bistable system driven by cross-correlated noise are investigated. The expressions for the average escape time from the left metastable state T L and from the right metastable state T R are derived. The results indicate that: i) The NES effect is suppressed as the correlation time τ increases for two metastable states; ii) The increase in τ speeds up the escape process from the right state for positively correlated noise, whereas its role is reverses for negatively correlated;iii) In the escape process from the left state, the role of τ is opposite to that in escape from the right state.