Delay-induced deterministic resonance of chaotic dynamics

Abstract

We show that time-delayed feedback can induce an optimal regularity in the pulsating dynamics of a nonlinear system without the need for an additional noise source. This deterministic delay-induced coherence resonance is reported experimentally in the chaotic dynamics of a laser diode subject to a phase-conjugate optical feedback, when varying the amount of feedback light. Qualitatively similar resonance is found theoretically in the model of a time-delayed class-A laser. The resonance is therefore not related to an interplay between time-delayed dynamics and faster undamped relaxation oscillations and is thought to be generic for a large class of delayed nonlinear systems.