Growing Surface Tension of Amorphous-Amorphous Interfaces on Approaching the Colloidal Glass Transition

Abstract

There is mounting evidence indicating that relaxation dynamics in liquids approaching their glass transition not only becomes increasingly cooperative (1,2) but the relaxing regions also become more compact in shape(3-7). While the surface tension of the interface separating neighboring relaxing regions is thought to play a crucial role in deciding both their size and morphology(8-10), owing to the amorphous nature of these regions, even identifying these interfaces has not been possible in bulk liquids. Here, by devising a scheme to identify self-induced disorder sites in bulk colloidal liquids, we directly quantified the dynamics of interfaces delineating regions of high and low configurational overlap. This procedure also helped unveil a non-monotonicity in dynamical correlations that has never been observed in bulk supercooled liquids. Using the capillary fluctuation method (11,12), we measured the surface tension of amorphous-amorphous interfaces with supercooling and find that it increases rapidly across the mode-coupling area fraction. Remarkably, a similar growth in the surface tension is also seen in the presence of a pinned amorphous wall. Our observations help prune theories of glass formation and opens up new research avenues aimed at tuning the properties of amorphous-amorphous interfaces, and hence the glass itself, in a manner analogous to grain boundary engineering in polycrystals (13).

References in corpus (9)

• Theoretical perspective on the glass transition and amorphous materials
• Supercooled Liquids for Pedestrians
• Configurational entropy measurements in extremely supercooled liquids that break the glass ceiling
• Direct measurements of growing amorphous order and non-monotonic dynamic correlations in a colloidal glass-former
• Finite size effects in the dynamics of glass-forming liquids
• The equilibrium intrinsic crystal-liquid interface of colloids
• Deconstructing the glass transition through critical experiments on colloids
• Non-linear dynamic response of glass-forming liquids to random pinning
• Excess free energy of supercooled liquids at disordered walls

Cited by in corpus (8)

• Colloidal Hard Spheres: Triumphs, Challenges and Mysteries
• Does the Adam-Gibbs relation hold in simulated supercooled liquids?
• Effect of pinning on the yielding transition of amorphous solids
• The glass transition in molecules, colloids and grains: universality and specificity
• Fragile-to-Strong Crossover, growing length scales, and dynamic heterogeneity in Wigner Glasses
• Concentrated suspensions of Brownian beads in water: dynamic heterogeneities trough a simple experimental technique
• Surface melting of a colloidal glass
• Static self-induced heterogeneity in glass-forming liquids: Overlap as a microscope