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Grain boundary dynamics in stripe phases of non potential systems

Zhi-Feng Huang·Jorge Vinals
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Abstract

We describe numerical solutions of two non potential models of pattern formation in nonequilibrium systems to address the motion and decay of grain boundaries separating domains of stripe configurations of different orientations. We first address wavenumber selection because of the boundary, and possible decay modes when the periodicity of the stripe phases is different from the selected wavenumber for a stationary boundary. We discuss several decay modes including long wavelength undulations of the moving boundary as well as the formation of localized defects and their subsequent motion. We find three different regimes as a function of the distance to the stripe phase threshold and initial wavenumber, and then correlate these findings with domain morphology during domain coarsening in a large aspect ratio configuration.

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Zhi-Feng Huang, Jorge Vinals. 2006-12-11. Grain boundary dynamics in stripe phases of non potential systems. https://doi.org/10.1103/physreve.75.056202

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