Diffusion-Induced Oscillations of Extended Defects

Alexander L. Korzhenevskii; Richard Bausch; Rudi Schmitz

doi:10.1103/physrevlett.108.046101

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arXiv · 1112.3669

Diffusion-Induced Oscillations of Extended Defects

Alexander L. Korzhenevskii·Richard Bausch·Rudi Schmitz

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Abstract

From a simple model for the driven motion of a planar interface under the influence of a diffusion field we derive a damped nonlinear oscillator equation for the interface position. Inside an unstable regime, where the damping term is negative, we find limit-cycle solutions, describing an oscillatory propagation of the interface. In case of a growing solidification front this offers a transparent scenario for the formation of solute bands in binary alloys, and, taking into account the Mullins-Sekerka instability, of banded structures.

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Alexander L. Korzhenevskii, Richard Bausch, Rudi Schmitz. 2011-12-15. Diffusion-Induced Oscillations of Extended Defects. https://doi.org/10.1103/physrevlett.108.046101

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