Dynamical Heterogeneity in Lattice Glass Models

TL;DR

This paper investigates dynamical heterogeneity in lattice glass models, revealing anisotropic particle motion, violations of the Stokes-Einstein relation, and growth of heterogeneity length scales, advancing understanding of glassy dynamics.

Contribution

Introduces a new lattice glass model that avoids crystallization and exhibits key glassy features, bridging thermodynamic considerations with dynamical heterogeneity.

Findings

Model displays anisotropic particle motion at intermediate times

Violates the Stokes-Einstein relation

Shows growth of dynamical heterogeneity length scales

Abstract

In this paper we consider in detail the properties of dynamical heterogeneity in lattice glass models (LGMs). LGMs are lattice models whose dynamical rules are based on thermodynamic, as opposed to purely kinetic, considerations. We devise a LGM that is not prone to crystallization and displays properties of a fragile glass-forming liquid. Particle motion in this model tends to be locally anisotropic on intermediate time scales even though the rules governing the model are isotropic. The model demonstrates violations of the Stokes-Einstein relation and the growth of various length scales associated with dynamical heterogeneity. We discuss future avenues of research comparing the predictions of lattice glass models and kinetically constrained models to atomistic systems.