Ultra-long-range dynamic correlations in a microscopic model for aging gels

TL;DR

This paper uses large-scale simulations to reveal that aging gels exhibit superdiffusive particle motion, large-scale spatial correlations, and intermittent heterogeneities, matching experimental observations of soft materials.

Contribution

It introduces the first microscopic model that reproduces all key features of aging dynamics in colloidal gels observed experimentally.

Findings

Superdiffusive particle motion during aging

Compressed exponential relaxation of correlation functions

Large-scale spatial correlations and heterogeneities

Abstract

We use large-scale computer simulations to explore the non-equilibrium aging dynamics in a microscopic model for colloidal gels. We find that gelation resulting from a kinetically-arrested phase separation is accompanied by `anomalous' particle dynamics revealed by superdiffusive particle motion and compressed exponential relaxation of time correlation functions. Spatio-temporal analysis of the dynamics reveals intermittent heterogeneities producing spatial correlations over extremely large length scales. Our study is the first microscopically-resolved model reproducing all features of the spontaneous aging dynamics observed experimentally in soft materials.