Dynamical Correlations near Dislocation Jamming

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Journal Title
Journal ISSN
Volume Title
School of Science | A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
Date
2010
Major/Subject
Mcode
Degree programme
Language
en
Pages
015501/1-4
Series
Physical Review Letters, Volume 105, Issue 1
Abstract
Dislocation assemblies exhibit a jamming or yielding transition at a critical external shear stress value σ=σc. Here we study the heterogeneous and collective nature of dislocation dynamics within a crystal plasticity model close to σc, by considering the first-passage properties of the dislocation dynamics. As the transition is approached in the moving phase, the first-passage time distribution exhibits scaling, and a related peak dynamical susceptibility χ∗4 diverges as χ∗4∼(σ−σc)−α, with α≈1.1. We relate this scaling to an avalanche description of the dynamics. While the static structural correlations are found to be independent of the external stress, we identify a diverging dynamical correlation length ξy in the direction perpendicular to the dislocation glide motion.
Description
Keywords
plasticity, dislocation dynamics
Other note
Citation
Laurson, Lasse & Miguel, M.-Carmen & Alava, Mikko J. 2010. Dynamical Correlations near Dislocation Jamming. Physical Review Letters. Volume 105, Issue 1. 015501/1-4. ISSN 0031-9007 (printed). DOI: 10.1103/physrevlett.105.015501.