Dynamical Facilitation Governs the Equilibration Dynamics of Glasses

Abstract

Convincing evidence of domain growth in the heating of ultrastable glasses suggests that the equilibration dynamics of super-cooled liquids could be driven by a nucleation and growth mechanism. We investigate this possibility by simulating the equilibration dynamics of a model glass during both heating and cooling between poorly and well-annealed states. Though we do observe the growth of domains during heating, we find that domains are absent during cooling. This absence is inconsistent with classical nucleation theory. By comparing the equilibration dynamics of our glass with that of two models with kinetic constraints, we demonstrate that dynamical facilitation generically leads to heating driven by domain growth and cooling without domains. Our results provide strong evidence that dynamical facilitation, not nucleation and interfacial-tension-driven domain growth, is the driving mechanism for the equilibration dynamics of glass-formers.

21 pages, 16 figures. Supplemental Movies too large for arXiv. Will provide download link once available. Available on request until then

References in corpus (14)

• Glassy dynamics of kinetically constrained models
• Thirty milliseconds in the life of a supercooled liquid
• Macroscopic Facilitation of Glassy Relaxation Kinetics: Ultra Stable Glass Films with Front-Like Thermal Response
• One micron length scale controls kinetic stability of low energy glasses
• Thermal stability of vapor-deposited stable glasses of an organic semiconductor
• Evidence for a disordered critical point in a glass-forming liquid
• Caging and mosaic lengthscales in plaquette spin models of glasses
• Density controls the kinetic stability of ultrastable glasses
• Enthalpy and high temperature relaxation kinetics of stable vapor-deposited glasses of toluene
• Equilibrium ultrastable glasses produced by random pinning
• Experimental evidence of a crossover between cooperative relaxation and liquid growth dynamics
• Two-step devitrification of ultrastable glasses
• Real-time microscopic view of the relaxation of a glass
• Front propagation in ultrastable glasses is dynamically heterogeneous

Cited by in corpus (5)

• Characterising the slow dynamics of the swap Monte Carlo algorithm
• Transmission of mobility via cooperative mechanisms in soft active matter
• Swap Monte Carlo for diatomic molecules
• Computational Methods toward Ultrastable Glasses
• Statistics of Thermal Avalanches in Driven Amorphous Systems