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arXiv · 1001.0914

Superdiffusive, heterogeneous, and collective particle motion near the jamming transition in athermal disordered materials

Claus Heussinger·Ludovic Berthier·Jean-Louis Barrat
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Abstract

We use computer simulations to study the microscopic dynamics of an athermal assembly of soft particles near the fluid-to-solid, jamming transition. Borrowing tools developed to study dynamic heterogeneity near glass transitions, we discover a number of original signatures of the jamming transition at the particle scale. We observe superdiffusive, spatially heterogeneous, and collective particle motion over a characteristic scale which displays a surprising non-monotonic behavior across the transition. In the solid phase, the dynamics is an intermittent succession of elastic deformations and plastic relaxations, which are both characterized by scale-free spatial correlations and system size dependent dynamic susceptibilities. Our results show that dynamic heterogeneities in dense athermal systems and glass-formers are very different, and shed light on recent experimental reports of `anomalous' dynamical behavior near the jamming transition of granular and colloidal assemblies.

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Claus Heussinger, Ludovic Berthier, Jean-Louis Barrat. 2010-06-23. Superdiffusive, heterogeneous, and collective particle motion near the jamming transition in athermal disordered materials. https://doi.org/10.1209/0295-5075%2F90%2F20005

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