Avalanche properties at the yielding transition: from externally deformed glasses to active systems

TL;DR

This study explores the universality of avalanche behaviors at the yielding transition in soft particle systems, comparing passive and active deformation scenarios through numerical simulations, revealing consistent avalanche exponents but differing flow dynamics.

Contribution

It demonstrates that avalanche size distributions are universal across passive and active systems, and analyzes how flow curve differences relate to avalanche propagation mechanisms.

Findings

Avalanche exponents are universal across different deformation modes.

Flow curve differences are linked to dynamic effects on avalanche propagation.

Plastic avalanches show similar scaling between size and relaxation time.

Abstract

We investigated the yielding phenomenon in the quasistatic limit using numerical simulations of soft particles. Two different deformation scenarios, simple shear (passive) and self-random force (active), and two interaction potentials were used. Our approach reveals that the exponents describing the avalanche distribution are universal within the margin of error, showing consistency between the passive and active systems. This indicates that any differences observed in the flow curves may have resulted from a dynamic effect on the avalanche propagation mechanism. The evolution time required to reach a steady state differs significantly between active and passive scenarios under similar conditions. However, we demonstrated that plastic avalanches under athermal quasistatic simulation dynamics display a similar scaling relationship between avalanche size and relaxation time, which cannot explain the different flow curves.