Front propagation in ultrastable glasses is dynamically heterogeneous

Abstract

Upon heating, ultrastable glassy films transform into liquids via a propagating equilibration front, resembling the heterogeneous melting of crystals. A microscopic understanding of this robust phenomenology is however lacking because experimental resolution is limited. We simulate the heterogeneous transformation kinetics of ultrastable configurations prepared using the swap Monte Carlo algorithm, thus allowing direct comparison with experiments. We resolve the liquid-glass interface both in space and time as well as the underlying particle motion responsible for its propagation. We perform a detailed statistical analysis of the interface geometry and kinetics over a broad range of temperatures. We show that the dynamic heterogeneity of the bulk liquid is passed on to the front which propagates heterogeneously in space and intermittently in time. This observation allows us to relate the averaged front velocity to the equilibrium diffusion coefficient of the liquid. We suggest that an experimental characterisation of the interface geometry during the heterogeneous devitrification of ultrastable glassy films would provide direct experimental access to the long-sought characteristic lengthscale of dynamic heterogeneity in bulk supercooled liquids.

References in corpus (37)

• Theoretical perspective on the glass transition and amorphous materials
• Dynamical heterogeneities in a supercooled Lennard-Jones liquid
• Direct experimental evidence of a growing length scale accompanying the glass transition
• Dynamics on the Way to Forming Glass: Bubbles in Space-time
• Universal nature of particle displacements close to glass and jamming transitions
• Models and algorithms for the next generation of glass transition studies
• Spatial correlations in the dynamics of glassforming liquids: Experimental determination of their temperature dependence
• Perspective: Highly stable vapor-deposited glasses
• Length scale for the onset of Fickian diffusion in supercooled liquids
• Facets of glass physics
• Equilibrium sampling of hard spheres up to the jamming density and beyond
• Mermin-Wagner fluctuations in 2D amorphous solids
• Fundamental differences between glassy dynamics in two and three dimensions
• Spatially Heterogeneous Dynamics in a Metallic Glass Forming Liquid Imaged by Electron Correlation Microscopy
• Thirty milliseconds in the life of a supercooled liquid
• Modern computational studies of the glass transition
• Zero-temperature glass transition in two dimensions
• Dynamic heterogeneity in a glass forming fluid: susceptibility, structure factor and correlation length
• Macroscopic Facilitation of Glassy Relaxation Kinetics: Ultra Stable Glass Films with Front-Like Thermal Response
• Model Vapor-Deposited Glasses: Growth Front and Composition Effects
• One micron length scale controls kinetic stability of low energy glasses
• Microscopic origin of excess wings in relaxation spectra of supercooled liquids
• Efficient swap algorithms for molecular dynamics simulations of equilibrium supercooled liquids
• Thermal stability of vapor-deposited stable glasses of an organic semiconductor
• Picosecond Dynamic Heterogeneity, Hopping and Johari-Goldstein Relaxation in Glassforming Liquids
• Density controls the kinetic stability of ultrastable glasses
• How to "measure" a structural relaxation time that is too long to be measured?
• 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
• The melting of stable glasses is governed by nucleation-and-growth dynamics
• Fluctuating Mobility Generation and Transport in Glasses
• Front-mediated melting of ultrastable glasses
• Real-time microscopic view of the relaxation of a glass
• Front propagation versus bulk relaxation in the annealing dynamics of a kinetically constrained model of ultrastable glasses
• Is glass a state of matter?

Cited by in corpus (6)

• Direct numerical analysis of dynamic facilitation in glass-forming liquids
• Dynamical Facilitation Governs the Equilibration Dynamics of Glasses
• High density two-component glasses of organic semiconductors prepared by physical vapor deposition
• Characterising the slow dynamics of the swap Monte Carlo algorithm
• Swap Monte Carlo for diatomic molecules
• Initial Stages of Rejuvenation of Vapor-Deposited Glasses during Isothermal Annealing: Contrast Between Experiment and Simulation