Noise-Induced Entrainment between Two Coupled Chemical Oscillators in Belouzov-Zhabotinsky Reactions

Kazuyuki Fujii¹, Daisuke Hayashi¹, Osamu Inomoto^1,2 and Shoichi Kai¹

¹Department of Applied Physics, Kyushu University, Fukuoka 812-8581, Japan
E-mail: kaitap@mbox.nc.kyushu-u.ac.jp
²Optical Engineering Laboratory, The Institute of Physical and Chemical Research, Hirosawa 2-1, Wako, Saitama 351-0198, Japan
E-mail:inomoto@postman.riken.go.jp

(Received April 19, 2000; Accepted May 19, 2000)

Keywords: Noise Synchronization, Stochastic Resonance, Entrainment, Chemical Oscillation, BZ Reaction

Abstract. The entrainment dynamics of two chemical-oscillators in an excitable medium separated by some distance d was experimentally studied in the light-sensitive Belousov-Zhabotinsky reaction under application of external noise. Two chemical-oscillators were always spontaneously synchronized at sufficiently small d or frequency difference in the absence of noise. For insufficient distance to entrain each other, however, the frequency and phase were self-synchronized by application of noise. Increasing the noise intensity the entrainment frequency area between two oscillators increased and showed a maximum at a certain noise intensity, that is, an optimum noise intensity existed. We call this the noise-synchronaization phenomenon.