Universal scaling of the velocity field in crack front propagation

TL;DR

This paper demonstrates that analyzing velocity field correlations in crack front propagation reveals universal scaling laws and critical exponents, applicable to both simulations and experiments, advancing understanding of avalanche dynamics in disordered materials.

Contribution

It introduces a method using velocity correlation functions to identify universality classes and critical exponents in crack front avalanches, applicable across systems.

Findings

Correlation functions yield critical exponents.

Universal scaling laws are confirmed in experiments and simulations.

Method is robust and extendable to other avalanche systems.

Abstract

The propagation of a crack front in disordered materials is jerky and characterized by bursts of activity, called avalanches. These phenomena are the manifestation of an out-of-equilibrium phase transition originated by the disorder. As a result avalanches display universal scalings which are however difficult to characterize in experiments at finite drive. Here we show that the correlation functions of the velocity field along the front allow to extract the critical exponents of the transition and to identify the universality class of the system. We employ these correlations to characterize the universal behavior of the transition in simulations and in an experiment of crack propagation. This analysis is robust, efficient and can be extended to all systems displaying avalanche dynamics.