A phase-separation perspective on dynamic heterogeneities in glass-forming liquids

TL;DR

This paper investigates dynamic heterogeneities in glass-forming liquids through a phase-separation lens, revealing that these heterogeneities are linked to a transient phase-separating regime with finite surface tension.

Contribution

It introduces a phase-separation perspective to understand dynamic heterogeneities, supported by thermodynamic calculations indicating spinodal decomposition in a model glass-former.

Findings

Evidence of phase separation into regions of different overlap.

Thermodynamic potential shows a Maxwell's construction.

Dynamic heterogeneities linked to a transient phase-separating regime.

Abstract

We study dynamic heterogeneities in a model glass-former whose overlap with a reference configuration is constrained to a fixed value. The system phase-separates into regions of small and large overlap, so that dynamical correlations remain strong even for asymptotic times. We calculate an appropriate thermodynamic potential and find evidence of a Maxwell's construction consistent with a spinodal decomposition of two phases. Our results suggest that dynamic heterogeneities are the expression of an ephemeral phase-separating regime ruled by a finite surface tension.