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arXiv · 1108.5688

Shocks near Jamming

Leopoldo R. Gomez·Ari M. Turner·Martin van Hecke·Vincenzo Vitelli
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Abstract

Non-linear sound is an extreme phenomenon typically observed in solids after violent explosions. But granular media are different. Right when they jam, these fragile and disordered solids exhibit a vanishing rigidity and sound speed, so that even tiny mechanical perturbations form supersonic shocks. Here, we perform simulations in which two-dimensional jammed granular packings are dynamically compressed, and demonstrate that the elementary excitations are strongly non-linear shocks, rather than ordinary phonons. We capture the full dependence of the shock speed on pressure and impact intensity by a surprisingly simple analytical model.

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Leopoldo R. Gomez, Ari M. Turner, Martin van Hecke, Vincenzo Vitelli. 2011-12-07. Shocks near Jamming. https://doi.org/10.1103/physrevlett.108.058001

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