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arXiv · 1405.0414

Unusual synchronization phenomena during electrodissolution of silicon: the role of nonlinear global coupling

Abstract

The photoelectrodissolution of n-type silicon constitutes a convenient model system to study the nonlinear dynamics of oscillatory media. On the silicon surface, a silicon oxide layer forms. In the lateral direction, the thickness of this layer is not uniform. Rather, several spatio-temporal patterns in the oxide layer emerge spontaneously, ranging from cluster patterns and turbulence to quite peculiar dynamics like chimera states. Introducing a nonlinear global coupling in the complex Ginzburg-Landau equation allows us to identify this nonlinear coupling as the essential ingredient to describe the patterns found in the experiments. The nonlinear global coupling is designed in such a way, as to capture an important, experimentally observed feature: the spatially averaged oxide-layer thickness shows nearly harmonic oscillations. Simulations of the modified complex Ginzburg-Landau equation capture the experimental dynamics very well.

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Lennart Schmidt, Konrad Schönleber, Vladimir García-Morales, Katharina Krischer. 2014-05-02. Unusual synchronization phenomena during electrodissolution of silicon: the role of nonlinear global coupling. https://doi.org/10.1142/9789814616133_0014

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