Direct numerical analysis of dynamic facilitation in glass-forming liquids

Cecilia Herrero; Ludovic Berthier

doi:10.1103/physrevlett.132.258201

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arXiv · 2310.16935

Direct numerical analysis of dynamic facilitation in glass-forming liquids

Cecilia Herrero·Ludovic Berthier

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Abstract

We propose a computational strategy to quantify the temperature evolution of the timescales and lengthscales over which dynamic facilitation affects the relaxation dynamics of glass-forming liquids at low temperatures, that requires no assumption about the nature of the dynamics. In two glass models, we find that dynamic facilitation depends strongly on temperature, leading to a subdiffusive spreading of relaxation events which we characterize using a temperature-dependent dynamic exponent. We also establish that this temperature evolution represents a major contribution to the increase of the structural relaxation time.

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Cecilia Herrero, Ludovic Berthier. 2023-10-25. Direct numerical analysis of dynamic facilitation in glass-forming liquids. https://doi.org/10.1103/physrevlett.132.258201

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