Publication : t10/282
Super-diffusion around the rigidity transition: Lévy and the Lilliputians
Lechenault F. (CEA Saclay/SPCSI, Grp. Complex Systems and Fracture, F-91191 Gif-sur-Yvette, France)Candelier R. (LPS, Ecole Normale Sup´erieure, URA D 1306, 24 rue Lhomond 75005 Paris, France)
Dauchot O. (CEA, IRAMIS, SPEC (Service de Physique de lEtat Condensé), F-91191 Gif-sur-Yvette, FRANCE)
Bouchaud J.-P. (Science & Finance, Capital Fund Management 6 Bld Haussmann, F-75009 Paris, France)
Biroli G. (CEA, IPhT (Institut de Physique Théorique), F-91191 Gif-sur-Yvette, France)
Abstract:Année de publication : 2010
By analyzing the displacement statistics of an assembly of horizontally vibrated bidisperse frictional grains in the vicinity of the jamming transition experimentally studied before, we establish that their superdiffusive motion is a genuine Levy flight, but with `jump' size very small compared to the diameter of the grains. The vibration induces a broad distribution of jumps that are random in time, but correlated in space, and that can be interpreted as micro-crack events at all scales. As the volume fraction departs from the critical jamming density, this distribution is truncated at a smaller and smaller jump size, inducing a crossover towards standard diffusive motion at long times. This interpretation contrasts with the idea of temporally persistent, spatially correlated currents and raises new issues regarding the analysis of the dynamics in terms of vibrational modes.
Revue : Soft Matter 6 3059-3064 (2010)
DOI : 10.1039/C000802H
Preprint : arXiv:1001.1765v1
Langue : Anglais
NB : 6 figures
Fichier(s) à télécharger :
publi.pdf
