From Inherent Structures Deformation to Elastic Heterogeneities

TL;DR

This study investigates the relationship between dynamical heterogeneities and elastic heterogeneities in glassy materials using molecular dynamics simulations, revealing that their characteristic length scales converge at low temperatures.

Contribution

It introduces a novel deformation protocol and compares it with isoconfigurational ensemble methods to connect dynamical and elastic heterogeneities in glasses.

Findings

Length scales grow as temperature decreases.

Both methods show identical trend in length scale evolution.

Length scales converge to characterize elastic heterogeneities at low temperatures.

Abstract

Using a well defined soft model glass in the framework of Molecular Dynamics simulations, the inherent structures are probed by means of a recently developed deformation protocol that aims to capture the Dynamical Heterogeneities (DH), as well as by the use of the isoconfigurational ensemble. Comparisons of both methods are performed by extracting the corresponding inherent characteristic length scales as the temperature of the system is cooled down from the liquid to the glassy state. The obtained lengths grow and depict an identical trend as the system falls out-off equilibrium, and appear to converge to the characteristic length scale that characterizes the Elastic Heterogeneities (EH) of the materials in the very low temperature limit, which is deeply related to the properties of the glass. This provides a first evidence of a relationship between DH and EH.