Modulating coherence resonance in non-excitable systems by time-delayed feedback

Abstract

We propose a paradigmatic model system, a subcritical Hopf normal form subjected to noiseand time-delayed feedback, to investigate the impact of time delay on coherence resonancein non-excitable systems. We develop analytical tools to estimate the stationarydistribution and the time correlations in nonlinear stochastic delay differentialequations. These tools are applied to our model to propose a novel quantity to measurecoherence resonance induced by a saddle-node bifurcation of periodic orbits.