Multiple length and time scales of dynamic heterogeneities in model glass-forming liquids: A systematic analysis of multi-point and multi-time correlations

Abstract

We report an extensive and systematic investigation of the multi-point and multi-time correlation functions to reveal the spatio-temporal structures of dynamic heterogeneities in glass-forming liquids. Molecular dynamics simulations are carried out for the supercooled states of various prototype models of glass-forming liquids such as binary Kob-Andersen, Wahnstrom, soft-sphere, and network-forming liquids. First, we quantify the length scale of the dynamic heterogeneities utilizing the four-point correlation function. The growth of the dynamic length scale with decreasing temperature is characterized by various scaling relations that are analogous to the critical phenomena. We also examine how the growth of the length scale depends upon the model employed. Second, the four-point correlation function is extended to a three-time correlation function to characterize the temporal structures of the dynamic heterogeneities based on our previous studies. We provide comprehensive numerical results obtained from the three-time correlation function for the above models. From these calculations, we examine the time scale of the dynamic heterogeneities and determine the associated lifetime in a consistent and systematic way. Our results indicate that the lifetime of the dynamical heterogeneities becomes much longer than the alpha relaxation time determined from a two-point correlation function in fragile liquids. The decoupling between the two time scales is remarkable, particularly in supercooled states, and the time scales differ by more than an order of magnitude in a more fragile liquid. In contrast, the lifetime is shorter than the alpha-relaxation time in tetrahedral network-forming strong liquid, even at lower temperatures.

12 pages, 10 figures, submitted to J. Chem. Phys. for "Special Topic Issue on the Glass Transition"

References in corpus (31)

• Theoretical perspective on the glass transition and amorphous materials
• Supercooled Liquids for Pedestrians
• Irreversible reorganization in a supercooled liquid originates from localised soft modes
• Probing the equilibrium dynamics of colloidal hard spheres above the mode-coupling glass transition
• Inhomogeneous Mode-Coupling Theory and Growing Dynamic Length in Supercooled Liquids
• Roles of icosahedral and crystal-like order in hard spheres glass transition
• Growing length and time scales in glass forming liquids
• Spatial correlations in the dynamics of glassforming liquids: Experimental determination of their temperature dependence
• Spontaneous and induced dynamic fluctuations in glass-formers I: General results and dependence on ensemble and dynamics
• Dynamic heterogeneity in amorphous materials
• Excitation lines and the breakdown of Stokes-Einstein relations in supercooled liquids
• Understanding fragility in supercooled Lennard-Jones mixtures. I. Locally preferred structures
• Spontaneous and induced dynamic correlations in glass-formers II: Model calculations and comparison to numerical simulations
• Heterogeneous Dynamics, Marginal Stability and Soft Modes in Hard Sphere Glasses
• Mosaic multi-state scenario vs. one-state description of supercooled liquids
• Dynamical Exchanges in Facilitated Models of Supercooled liquids
• Lengthscale dependence of dynamic four-point susceptibilities in glass formers
• Locally preferred structures and many-body static correlations in viscous liquids
• The role of attractive forces in viscous liquids
• Finite size effects in the dynamics of glass-forming liquids
• A critical test of the mode-coupling theory of the glass transition
• Short and long range correlated motion observed in colloidal glasses and liquids
• Tuning the fragility of a glassforming liquid by curving space
• Revisiting the slow dynamics of a silica melt using Monte Carlo simulations
• Relationship between bond-breakage correlations and four-point correlations in heterogeneous glassy dynamics: Configuration changes and vibration modes
• Characterizing order in amorphous systems
• Multi-time density correlation functions in glass-forming liquids: Probing dynamical heterogeneity and its lifetime
• Four-point susceptibility of a glass-forming binary mixture: Brownian dynamics
• Multiple time scales hidden in heterogeneous dynamics of glass-forming liquids
• Dynamic heterogeneities in attractive colloids
• Suppression of the rate of growth of dynamic heterogeneities and its relation to the local structure in a supercooled polydisperse liquid

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• Frequency dependence of specific heat in supercooled liquid water and emergence of correlated dynamics
• The role of pair correlation function in the dynamical transition predicted by the mode coupling theory