Berlin 2024 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
DY: Fachverband Dynamik und Statistische Physik
DY 10: Nonlinear Dynamics, Synchronization and Chaos
DY 10.12: Talk
Monday, March 18, 2024, 18:00–18:15, BH-N 128
Patched patterns and emergence of chaotic interfaces: a new paradigm in coupled excitable systems — •Igor Franovic1 and Sebastian Eydam2 — 1Institute of Physics Belgrade, Serbia — 2RIKEN Center for Brain Science, Wako, Japan
While coherence-incoherence patterns have been extensively explored for coupled oscillators, much less is known about onset mechanisms and finite-size effects associated with such patterns in coupled excitable systems. Here we present a new class of patterns, called patched patterns, in non-locally coupled arrays of excitable units with attractive and repulsive interactions. Their self-organization involves the formation of patches, the spatial domains of units locked by their average spiking frequencies. Depending on the prevalence of attraction vs repulsion, patched patterns can be temporally periodic, quasiperiodic or chaotic, whereby in contrast to chimeras, chaos is not spatially localized. Chaotic patterns may develop interfaces where the units display a slow alternation between epochs of locking to adjacent patches and epochs of increased variability. We demonstrate typical bifurcation scenarios giving rise to chaos, showing that adapting the coupling range may change the character of the transition to chaos. Unlike chimeras, the maximal Lyapunov exponent for chaotic patched patterns converges to a finite value with system size. Nevertheless, interfaces may undergo an unpinning transition, which leads to diffusive motion similar to that of the incoherent part of chimeras.
Reference: I. Franović and S. R. Eydam, Chaos 32, 091102 (2022), https://doi.org/10.1063/5.0111507
Keywords: coherence-incoherence patterns; coupled excitable systems; frequency synchronization; chaotic interfaces; diffusive motion