Spiral wave dynamics under traveling-wave modulation of excitable mediaS. Zykov1, 2, V. S. Zykov1 and V. Davydov2
1 Institut für Theoretische Physik, Technische Universität Berlin D-10623 Berlin, Germany
2 Moscow Institute of Radioengineering, Electronics, and Automation 117454 Moscow, Russia
received 7 November 2005; accepted in final form 7 December 2005
published online 23 December 2005
We study dynamics of spiral waves in excitable media under spatio-temporal forcing in the form of a traveling-wave modulation of a control parameter. Within a certain range of the modulation frequency a synchronized drift of a spiral wave along a straight line is obtained. A complicated cycloidal-like motion occurs outside this synchronization band. Although circulation of the spiral wave tip is in-phase with external modulation, its rotation frequency is not locked by the applied perturbation. These numerical results obtained for the Oreganator model are confirmed and complemented by analysis of a simplified kinematical model. It is shown that the observed paradoxical phase synchronization is caused by Doppler shift of the modulation frequency in a coordinate system comoving with the spiral wave core.
05.45.-a - Nonlinear dynamics and nonlinear dynamical systems.
82.40.Ck - Pattern formation in reactions with diffusion, flow, and heat transfer.
05.45.Xt - Synchronization, coupled oscillators.
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