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arXiv · 1005.3794

Dynamic heterogeneity in a glass forming fluid: susceptibility, structure factor and correlation length

Elijah Flenner·Grzegorz Szamel
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Abstract

We investigate the growth of dynamic heterogeneity in a glassy hard-sphere mixture for volume fractions up to and including the mode-coupling transition. We use an 80 000 particle system to test a new procedure to evaluate a dynamic correlation length xi(t): we determine the ensemble independent dynamic susceptibility chi_4(t) and use it to facilitate evaluation of xi(t) from the small wave vector behavior of the four-point structure factor. We analyze relations between the alpha relaxation time tau_alpha, chi_4(tau_alpha), and xi(tau_alpha). We find that mode-coupling like power laws provide a reasonable description of the data over a restricted range of volume fractions, but the power laws' exponents differ from those predicted by the inhomogeneous mode-coupling theory. We find xi(tau_alpha) ~ ln(tau_alpha) over the full range of volume fractions studied, which is consistent with Adams-Gibbs-type relation.

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Elijah Flenner, Grzegorz Szamel. 2010-11-04. Dynamic heterogeneity in a glass forming fluid: susceptibility, structure factor and correlation length. https://doi.org/10.1103/physrevlett.105.217801

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