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Fingering Instability of Dislocations and Related Defects

Ming Li·Brian B. Smith·Robin L. B. Selinger
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Abstract

We identify a fundamental morphological instability of mobile dislocations in crystals and related line defects. A positive gradient in the local driving force along the direction of defect motion destabilizes long-wavelength vibrational modes, producing a ``fingering'' pattern. The minimum unstable wavelength scales as the inverse square root of the force gradient. We demonstrate the instability's onset in simulations of a screw dislocation in Al (via molecular dynamics) and of a vortex in a 3-d XY ``rotator'' model.

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Ming Li, Brian B. Smith, Robin L. B. Selinger. 1998-08-11. Fingering Instability of Dislocations and Related Defects. https://doi.org/10.1103/physrevlett.82.2306

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