Delay-enhanced coherent chaotic oscillations in networks with large disorders

Potsdam Institute for Climate Impact Research, DE-14473 Potsdam, Germany.
Physical Review E (Impact Factor: 2.33). 12/2011; 84(6 Pt 2):066206. DOI: 10.1103/PhysRevE.84.066206
Source: arXiv

ABSTRACT We study the effect of coupling delay in a regular network with a ring topology and in a more complex network with an all-to-all (global) topology in the presence of impurities (disorder). We find that the coupling delay is capable of inducing phase-coherent chaotic oscillations in both types of networks, thereby enhancing the spatiotemporal complexity even in the presence of 50% of symmetric disorders of both fixed and random types. Furthermore, the coupling delay increases the robustness of the networks up to 70% of disorders, thereby preventing the network from acquiring periodic oscillations to foster disorder-induced spatiotemporal order. We also confirm the enhancement of coherent chaotic oscillations using snapshots of the phases and values of the associated Kuramoto order parameter. We also explain a possible mechanism for the phenomenon of delay-induced coherent chaotic oscillations despite the presence of large disorders and discuss its applications.

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