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arXiv · nlin/0008035

Resonantly Forced Inhomogeneous Reaction-Diffusion Systems

Abstract

The dynamics of spatiotemporal patterns in oscillatory reaction-diffusion systems subject to periodic forcing with a spatially random forcing amplitude field are investigated. Quenched disorder is studied using the resonantly forced complex Ginzburg-Landau equation in the 3:1 resonance regime. Front roughening and spontaneous nucleation of target patterns are observed and characterized. Time dependent spatially varying forcing fields are studied in the 3:1 forced FitzHugh-Nagumo system. The periodic variation of the spatially random forcing amplitude breaks the symmetry among the three quasi-homogeneous states of the system, making the three types of fronts separating phases inequivalent. The resulting inequality in the front velocities leads to the formation of ``compound fronts'' with velocities lying between those of the individual component fronts, and ``pulses'' which are analogous structures arising from the combination of three fronts. Spiral wave dynamics is studied in systems with compound fronts.

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BibTeXRIS

C. J. Hemming, R. Kapral. 2000-08-29. Resonantly Forced Inhomogeneous Reaction-Diffusion Systems. https://doi.org/10.1063/1.1286264

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