Partial rejuvenation of a colloidal glass

F. Ozon (1) , T. Narita (1) , A. Knaebel (1) , G. Debrégeas (2) , P. Hébraud (3) , J. -P. Munch (1)

1 LDFC - Laboratoire de Dynamique des Fluides Complexes
2 LPMC - Laboratoire de Physique de la Matière Condensée
3 LPCM - Laboratoire de Physico-Chimie Macromoléculaire (UMR 7615)

We study the effect of shear on the aging dynamics of a colloidal suspension of synthetic clay particles. We find that a shear of amplitude $\gamma$ reduces the relaxation time measured just after the cessation of shear by a factor $\exp(-\gamma/\gamma_c)$, with $\gamma_c \sim 5%$, and is independent of the duration and the frequency of the shear. This simple law for the rejuvenation effect shows that the energy involved in colloidal rearrangements is proportional to the shear amplitude, $\gamma$, rather than $\gamma^2$, leading to an Eyring-like description of the dynamics of our system.

Domaines: Matière Molle [cond-mat.soft]; Mécanique statistique [cond-mat.stat-mech]

F. Ozon, T. Narita, A. Knaebel, G. Debrégeas, P. Hébraud, et al.. Partial rejuvenation of a colloidal glass. Physical Review E : Statistical, Nonlinear, and Soft Matter Physics, 2003, 68, pp.032401. ⟨hal-00138276⟩