Heterogeneous diffusion in a reversible gel

Pablo I. Hurtado; Ludovic Berthier; Walter Kob

doi:10.1103/physrevlett.98.135503

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arXiv · cond-mat/0612513

Heterogeneous diffusion in a reversible gel

Pablo I. Hurtado·Ludovic Berthier·Walter Kob

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Abstract

We introduce a microscopically realistic model of a physical gel and use computer simulations to study its static and dynamic properties at thermal equilibrium. The phase diagram comprises a sol phase, a coexistence region ending at a critical point, a gelation line determined by geometric percolation, and an equilibrium gel phase unrelated to phase separation. The global structure of the gel is homogeneous, but the stress is supported by a fractal network. The gel dynamics is highly heterogeneous and we propose a theoretical model to quantitatively describe dynamic heterogeneity in gels. We elucidate several differences between the dynamics of gels and that of glass-formers.

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Pablo I. Hurtado, Ludovic Berthier, Walter Kob. 2007-03-29. Heterogeneous diffusion in a reversible gel. https://doi.org/10.1103/physrevlett.98.135503

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