title: Relaxation in yield stress systems through elastically interacting activated events.
abstract: We study consequences of long-range elasticity in thermally assisted dynamics of yield stress materials. Within a two-dimensional mesoscopic model we calculate the mean-square displacement and the dynamical structure factor for tracer particle trajectories. The ballistic regime at short time scales is associated with a compressed exponential decay in the dynamical structure factor, followed by a subdiffusive crossover prior to the onset of diffusion. We relate this crossover to spatiotemporal correlations and thus go beyond established mean field predictions.
authors.affiliation: Université Grenoble Alpes, LIPHY, F-38000 Grenoble, France and CNRS, LIPHY, F-38000 Grenoble, France.
authors.forename: Ezequiel E
authors.initials: EE
authors.lastname: Ferrero
authors.affiliation: Université Grenoble Alpes, LIPHY, F-38000 Grenoble, France and CNRS, LIPHY, F-38000 Grenoble, France.
authors.forename: Kirsten
authors.initials: K
authors.lastname: Martens
authors.affiliation: Université Grenoble Alpes, LIPHY, F-38000 Grenoble, France and CNRS, LIPHY, F-38000 Grenoble, France.
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Barrat