Spatial heterogeneities in structural temperature cause Kovacs expansion gap paradox in aging of glasses
arXiv:1909.03685 · doi:10.1103/PhysRevLett.124.095501
Abstract
Volume and enthalpy relaxation of glasses after a sudden temperature change has been extensively studied since Kovacs seminal work. One observes an asymmetric approach to equilibrium upon cooling versus heating and, more counter-intuitively, the expansion gap paradox, i.e. a dependence on the initial temperature of the effective relaxation time even close to equilibrium when heating. Here we show that a distinguishable-particles lattice model can capture both the asymmetry and the expansion gap. We quantitatively characterize the energetic states of the particles configurations using a physical realization of the fictive temperature called the structural temperature, which, in the heating case, displays a strong spatial heterogeneity. The system relaxes by nucleation and expansion of warmer mobile domains having attained the final temperature, against cooler immobile domains maintained at the initial temperature. A small population of these cooler regions persists close to equilibrium, thus explaining the paradox.
arXiv commentMain text: 6 pages, 3 figures. Supplemental: 2 pages, 2 figures and 2 videos
References in corpus (10)
- Theoretical perspective on the glass transition and amorphous materials
- Spatially Heterogeneous Dynamics in a Metallic Glass Forming Liquid Imaged by Electron Correlation Microscopy
- Physical aging studied by a device allowing for rapid thermal equilibration
- Physical ageing studied by a device allowing for rapid thermal equilibration
- Calorimetric glass transition explained by hierarchical dynamic facilitation
- Direct tests of single-parameter aging
- Emergent facilitation behavior in a distinguishable-particle lattice model of glass
- Local random configuration-tree theory for string repetition and facilitated dynamics of glass
- Configuration-tree Theoretical Calculation of the Mean-Squared Displacement of Particles in Glass Formers
- A molecular perspective on the yield and flow of polymer glasses: The role of enhanced segmental dynamics during active deformation
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