Inherent-State Melting and the Onset of Glassy Dynamics in Two-Dimensional Supercooled Liquids

Abstract

Below the onset temperature $T_{\text{o}}$, the equilibrium relaxation time of most glass-forming liquids exhibits glassy dynamics characterized by super-Arrhenius temperature dependence. In this supercooled regime, the relaxation dynamics also proceeds through localized elastic excitations corresponding to hopping events between inherent states, i.e., potential-energy minimizing configurations of the liquid. Despite its importance in distinguishing the supercooled regime from the high-temperature regime, the microscopic origin of $T_{\text{o}}$ is not yet known. Here, we construct a theory for the onset temperature in two dimensions and find that inherent-state melting transition, described by the binding-unbinding transition of dipolar elastic excitations, delineates the supercooled regime from the high-temperature regime. The corresponding melting transition temperature is in good agreement with the onset temperature found in various two-dimensional atomistic models of glass formers. We discuss the predictions of our theory on the displacement and density correlations of two-dimensional supercooled liquids, which are consistent with observations of the Mermin-Wagner fluctuations in recent experiments and molecular simulations.

8 pages, 4 figures, 1 table

References in corpus (10)

• Theoretical perspective on the glass transition and amorphous materials
• Supercooled Liquids for Pedestrians
• Glassy dynamics of kinetically constrained models
• Microscopic origin of excess wings in relaxation spectra of supercooled liquids
• Low-energy quasilocalized excitations in structural glasses
• Replica theory of the rigidity of structural glasses
• Elastoplasticity Mediates Dynamical Heterogeneity Below the Mode-Coupling Temperature
• A Theory of Localized Excitations in Supercooled Liquids
• Mean-field description for the architecture of low-energy excitations in glasses
• Inherent-State Melting and the Onset of Glassy Dynamics in Two-Dimensional Supercooled Liquids

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