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arXiv · 1407.8014

Relaxation in yield stress systems through elastically interacting activated events

Ezequiel E. Ferrero·Kirsten Martens·Jean-Louis Barrat
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Abstract

We study consequences of long-range elasticity in thermally assisted dynamics of yield stress materials. Within a two-dimensinal mesoscopic model we calculate the mean-square displacement and the dynamical structure factor for tracer particle trajectories. The ballistic regime at short time scales is associated with a compressed exponential decay in the dynamical structure factor, followed by a subdiffusive crossover prior to the onset of diffusion. We relate this crossover to spatiotemporal correlations and thus go beyond established mean field predictions.

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Ezequiel E. Ferrero, Kirsten Martens, Jean-Louis Barrat. 2014-11-26. Relaxation in yield stress systems through elastically interacting activated events. https://doi.org/10.1103/physrevlett.113.248301

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