Robustness of avalanche dynamics in sheared amorphous solids as probed by transverse diffusion

TL;DR

This study uses numerical simulations to analyze transverse diffusion in sheared amorphous solids, revealing persistent correlations between plastic events near the glass transition and showing avalanche sizes are temperature-independent up to 0.75 T_g.

Contribution

It provides the first extensive finite-size analysis of transverse diffusion in sheared 2D amorphous solids across various temperatures and strain rates.

Findings

Correlations between plastic events persist near T_g.

Average avalanche size remains stable up to 0.75 T_g.

Transverse diffusion coefficient exhibits qualitative and quantitative behaviors across conditions.

Abstract

Using numerical simulations, we perform an extensive finite-size analysis of the transverse diffusion coefficient in a sheared 2D amorphous solid, over a broad range of strain rates, at temperatures up to the supercooled liquid regime. We thus obtain direct qualitative evidence for the persistence of correlations between elementary plastic events up to the vicinity of the glass transition temperature $T_g$. A quantitative analysis of the data, combined with a previous study of the $T$- and $\dot\gamma$-dependence of the macroscopic stress \cite{ChattorajCaroliLemaitre2010}, leads us to conclude that the average avalanche size remains essentially unaffected by temperature up to $T\sim0.75 T_g$.