Dynamical Effects Induced by Long Range Activation in a Nonequilibrium Reaction-Diffusion system.

M. FUENTES; M. N. KUPERMAN; J. BOISSONADE; E. DULOS; F. GAUFFRE; P. DE KEPPER

PHYSICAL REVIEW E - STATISTICAL PHYSICS, PLASMAS, FLUIDS AND RELATED INTERDISCIPLINARY TOPICS

Año: 2002 vol. 66 p. 562051 - 5620510

1063-651X

We show both experimentally and numerically that the time scales separation introduced by long range activation can induce oscillations and excitability in nonequilibrium reaction-diffusion systems that would otherwise only exhibit bistability. Namely, we show that in the chlorite-tetrathionate reaction, where the autocatalytic species H1 diffuses faster than the substrates, the spatial bistability domain in the nonequilibrium phase diagram is extended with oscillatory and excitability domains. A simple model and a more realistic model qualitatively account for the observed dynamical behavior. The latter model provides quantitative agreement with the experiments.