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arXiv · 0906.1766

The central role of thermal collective strain in the relaxation of structure in a supercooled liquid

Asaph Widmer-Cooper·Peter Harrowell
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Abstract

The spatial distribution of structural relaxation in a supercooled liquid is studied using molecular dynamics simulations of a 2D binary mixture. It is shown that the spatial heterogeneity of the relaxation along with the time scale of the relaxation is determined, not by the frequency with which particles move a distance pi/2kBragg, but by the frequency with which particles can achieve persistent displacements. We show that these persistent displacements are achieved through the coupled action of local reorganizations and unrecoverable thermal strains.

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Asaph Widmer-Cooper, Peter Harrowell. 2009-10-11. The central role of thermal collective strain in the relaxation of structure in a supercooled liquid. https://doi.org/10.1103/physreve.80.061501

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