Consequences of kinetic inhomogeneities in glasses

Abstract

Many of the physical pictures used to rationalize the phenomenology of glassy dynamics rest upon a consideration of spatial fluctuations in the relaxation kinetics of the glass-forming liquid. We examine the wide ranging consequences which flow from assuming the existence of transient kinetic inhomogeneities. These consequences include: strong and fragile behavior, two-step relaxation processes, nonlinear relaxation following temperature jumps, spatially correlated kinetics and non-Gaussian behavior of incoherent processes. These general predictions are explored in simulations in which relaxation is governed by diffusing defects. © 1996 The American Physical Society.