Coupled Ginzburg-Landau equations appear in a variety of contexts
involving instabilities in oscillatory media. When the relevant
unstable mode is of vectorial character (a common situation in
nonlinear optics), the pair of coupled equations has special
symmetries and can be written as a {\sl vector complex
Ginzburg-Landau equation}. Dynamical properties of localized
structures of topological character in this vector-field case are
considered. Creation and annihilation processes of different kinds
of vector defects are described, and some of them interpreted in
theoretical terms. A transition between different regimes of
spatiotemporal dynamics is described.
Keywords: Vector Ginzburg-Landau equation (VCGL), topological defects, spatiotemporal chaos, optical instabilities, light
polarization.
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http://ifisc.uib-csic.es/physdept/Nonlinear/research_topics/Vcgl2/.