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

• DOI: 10.1063/1.4769256
• Publication Date: 2013-01-03T06:34:57Z
• Authors: Kang Kim; Shinji Saito
• Keywords: Supercooling; Length scale; Dynamical heterogeneity

We report an extensive and systematic investigation of the multi-point multi-time correlation functions to reveal spatio-temporal structures dynamic heterogeneities in glass-forming liquids. Molecular dynamics simulations are carried out for supercooled states various prototype models liquids such as binary Kob-Andersen, Wahnström, soft-sphere, network-forming While first three act fragile exhibiting super-Arrhenius temperature dependence their relaxation times, last is a strong glass-former Arrhenius behavior. First, we quantify length scale utilizing four-point function. The growth with decreasing characterized by scaling relations that analogous critical phenomena. also examine how depends upon model employed. Second, function extended three-time characterize temporal based on our previous studies [K. Kim S. Saito, Phys. Rev. E 79, 060501(R) (2009); J. Chem. 133, 044511 (2010)]. provide comprehensive numerical results obtained from above models. From these calculations, time determine associated lifetime consistent way. Our indicate dynamical becomes much longer than α-relaxation determined two-point decoupling between two scales remarkable, particularly states, differ more order magnitude liquid. In contrast, shorter tetrahedral liquid, even at lower temperatures.