IFISUR   23398
INSTITUTO DE FISICA DEL SUR
Unidad Ejecutora - UE
artículos
Título:
Shocks near Jamming
Autor/es:
L. R. GÓMEZ; A. M. TURNER; M. VAN HECKE; V. VITELLI
Revista:
PHYSICAL REVIEW LETTERS
Editorial:
AMER PHYSICAL SOC
Referencias:
Lugar: New York; Año: 2012 vol. 108 p. 580011 - 580015
ISSN:
0031-9007
Resumen:
Nonlinear 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 nonlinear 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.