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arXiv · cond-mat/0610489

Caging dynamics in a granular fluid

Pedro M. Reis·Rohit A. Ingale·Mark D. Shattuck
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Abstract

We report an experimental investigation of the caging motion in a uniformly heated granular fluid, for a wide range of filling fractions, $ϕ$. At low $ϕ$ the classic diffusive behavior of a fluid is observed. However, as $ϕ$ is increased, temporary cages develop and particles become increasingly trapped by their neighbors. We statistically analyze particle trajectories and observe a number of robust features typically associated with dense molecular liquids and colloids. Even though our monodisperse and quasi-2D system is known to not exhibit a glass transition, we still observe many of the precursors usually associated with glassy dynamics. We speculate that this is due to a process of structural arrest provided, in our case, by the presence of crystallization.

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Pedro M. Reis, Rohit A. Ingale, Mark D. Shattuck. 2006-10-17. Caging dynamics in a granular fluid. https://doi.org/10.1103/physrevlett.98.188301

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