Shocks near Jamming
Soft Condensed Matter
2013-05-30 v2 Materials Science
Statistical Mechanics
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.
Cite
@article{arxiv.1108.5688,
title = {Shocks near Jamming},
author = {Leopoldo R. Gomez and Ari M. Turner and Martin van Hecke and Vincenzo Vitelli},
journal= {arXiv preprint arXiv:1108.5688},
year = {2013}
}
Comments
Revised version. Accepted for publication in Phys. Rev. Lett