Allgemeines Physikalisches Kolloquium im Wintersemester 2012/2013
Ort: 48149 Münster, Wilhelm-Klemm-Str. 10, IG I, HS 2,
Zeit: Donnerstag, 13.12.2012 16:00 Uhr c.t.
Kolloquiums-Kaffee ab 15:45 Uhr vor dem Hörsaal
Instabilities of self-organized structures in dissipative systems with delayed feedback
Dr. Svetlana Gurevich, Institut für Theoretische Physik, WWU Münster
During the last decade, control of complex irregular dynamics has evolved as one of the central issues in
applied nonlinear science. In particular, control of solitary localized structures in dissipative systems has
been of increasing interest in recent years. A particularly simple and efficient control scheme is time delayed
feedback. Here, we discuss the stability of two-dimensional solitary localized structures subjected to
a delayed feedback. We shall show that the presence of the delay term leads to nontrivial instabilities
resulting in formation of complex spatio-temporal structures, e.g., oscillons, soliton rings, labyrinth patterns or moving structures. We provide a bifurcation analysis of the delayed system and derive a system of
order parameter equations explicitly describing the temporal evolution of the localized structure in the
vicinity of the bifurcation point. In addition, numerical simulations are carried out showing good agreement
with the analytical predictions.
Einladender: Fachbereich Physik
Im Auftrag der Hochschullehrer des Fachbereichs Physik
Prof. Dr. Nikos Doltsinis