Plasticity of a colloidal polycrystal under cyclic shear Auteur(s): Tamborini E., Cipelletti L., Ramos L. (Article) Publié: Physical Review Letters, vol. 113 p.078301 (2014) Texte intégral en Openaccess : Ref HAL: hal-01058850_v1 Ref Arxiv: 1311.1996 DOI: 10.1103/PhysRevLett.113.078301 WoS: 000341115700027 Ref. & Cit.: NASA ADS Exporter : BibTex | endNote 25 Citations Résumé: We use confocal microscopy and time-resolved light scattering to investigate plasticity in a colloidal polycrystal, following the evolution of the network of grain boundaries as the sample is submitted to thousands of shear deformation cycles. The grain boundary motion is found to be ballistic, with a velocity distribution function exhibiting non-trivial power law tails. The shear- induced dynamics initially slow down, similarly to the aging of the spontaneous dynamics in glassy materials, but eventually reach a steady state. Surprisingly, the cross-over time between the ini- tial aging regime and the steady state decreases with increasing probed length scale, hinting at a hierarchical organization of the grain boundary dynamics. Commentaires: main paper + supplementary materials Journal: Phys. Rev. Lett., 113, 078301 (2014) |