Determination of the universality class of crystal plasticity

TL;DR

This study uses large-scale simulations of 2D dislocation dynamics to identify the universality class of crystal plasticity, finding it aligns with the mean-field interface depinning model.

Contribution

It provides the first comprehensive simulation-based evidence that crystal plasticity belongs to the mean-field universality class.

Findings

Avalanche scaling exponents match mean-field predictions

Avalanche profile scaling function agrees with interface depinning model

Static and dynamic universality classes are consistent with mean-field theory

Abstract

Although scaling phenomena have long been documented in crystalline plasticity, the universality class has been difficult to identify due to the rarity of avalanche events, which require large system sizes and long times in order to accurately measure scaling exponents and functions. Here we present comprehensive simulations of two-dimensional dislocation dynamics under shear, using finite-size scaling to extract scaling exponents and the avalanche profile scaling function from time-resolved measurements of slip-avalanches. Our results provide compelling evidence that both the static and dynamic universality classes are consistent with the mean-field interface depinning model.