title: Hysteresis and drift of spiral waves near heterogeneities: From chemical experiments to cardiac simulations.
abstract: Dissipative patterns in excitable reaction-diffusion systems can be strongly affected by spatial heterogeneities. Using the photosensitive Belousov-Zhabotinsky reaction, we show a hysteresis effect in the transition between free and pinned spiral rotation. The latter state involves the rotation around a disk-shaped obstacle with an impermeable and inert boundary. The transition is controlled by changes in light intensity. For permeable heterogeneities of higher excitability, we observe spiral drift along both linear and circular boundaries. Our results confirm recent theoretical predictions and, in the case of spiral drift, are further reproduced by numerical simulations with a modified Oregonator model. Additional simulations with a cardiac model show that orbital motion can also exist in anisotropic and three-dimensional systems.
authors.affiliation: Florida State University, Department of Chemistry and Biochemistry, Tallahassee, Florida 32306-4390, USA.
authors.forename: Elias
authors.initials: E
authors.lastname: Nakouzi
authors.affiliation: Institut für Theoretische Physik, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany.
authors.forename: Jan Frederik
authors.initials: JF
authors.lastname: Totz
authors.affiliation: Florida State University, Department of Chemistry and Biochemistry, Tallahassee, Florida 32306-4390, USA.
authors.forename: Zhihui
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Florida State University, Department of Chemistry and Biochemistry, Tallahassee, Florida 32306-4390, USA.
authors.forename: Oliver
authors.initials: O
authors.lastname: Steinbock
authors.affiliation: Institut für Theoretische Physik, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany.
authors.forename: Harald
authors.initials: H
authors.lastname: Engel