Avalanches in Strained Amorphous Solids: Does Inertia Destroy Critical Behavior?

TL;DR

This study investigates how inertia influences avalanche behavior in sheared amorphous solids, revealing that inertia shifts the system to a new universality class without destroying criticality.

Contribution

It demonstrates that inertia induces a new underdamped universality class in avalanches of amorphous solids, distinct from the overdamped case, and identifies the critical damping separating these regimes.

Findings

Inertia leads to a new universality class in avalanche behavior.

Overdamped universality persists even with underdamped vibrational modes.

Critical damping marks the transition between universality classes.

Abstract

Simulations are used to determine the effect of inertia on athermal shear of a two-dimensional binary Lennard-Jones glass. In the quasistatic limit, shear occurs through a series of rapid avalanches. The distribution of avalanches is analyzed using finite-size scaling with thousands to millions of particles. Inertia takes the system to a new underdamped universality class rather than driving the system away from criticality. Scaling exponents are determined for the underdamped and overdamped limits and a critical damping that separates the two regimes. Systems are in the overdamped universality class even when most vibrational modes are underdamped.