Hamburg 2001 – scientific programme
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DY: Dynamik und Statistische Physik
DY 46: Poster
DY 46.44: Poster
Thursday, March 29, 2001, 15:45–18:15, Foyer S\ 3
Transition from one-channel to global feedback control in excitable media — •On-Uma Kheowan1, Vladimir S. Zykov2, and Stefan C. Müller2 — 1Mahidol University, Department of Chemistry, Rama 6 Road, Bangkok 10400, Thailand — 2Institut für Experimentelle Physik, Otto-von-Guericke-Universität, Universitätsplatz 2, D-39106 Magdeburg, Germany
Dynamics of spiral waves in excitable media subjected to a feedback control is investigated. Spiral waves are induced in a thin layer of the light-sensitive Belousov-Zhabotinsky reaction and controlled by a time-dependent uniform illumination. The intensity of the illumination is taken to be proportional to the average wave activity observed within a circular area of the reaction layer. Variation of the diameter d of this area allows us to study a smooth transition from a one-channel (small d) to a global (large d) feedback control. Stabilization and destabilization of spiral waves, as well as the existence of new types of attractors are demonstrated and compared with results of numerical simulations.