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arXiv · 0709.1782

Supersonic dislocations observed in a plasma crystal

V. Nosenko·S. Zhdanov·G. Morfill
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Abstract

Experimental results on the dislocation dynamics in a two-dimensional plasma crystal are presented. Edge dislocations were created in pairs in lattice locations where the internal shear stress exceeded a threshold and then moved apart in the glide plane at a speed higher than the sound speed of shear waves, $C_T$. The experimental system, a plasma crystal, allowed observation of this process at an atomistic (kinetic) level. The early stage of this process is identified as a stacking fault. At a later stage, supersonically moving dislocations generated shear-wave Mach cones.

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V. Nosenko, S. Zhdanov, G. Morfill. 2007-09-12. Supersonic dislocations observed in a plasma crystal. https://doi.org/10.1103/physrevlett.99.025002

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