Relaxation in yield stress systems through elastically interacting activated events.

@article{Ferrero2014RelaxationIY,
  title={Relaxation in yield stress systems through elastically interacting activated events.},
  author={Ezequiel Ferrero and Kirsten Martens and Jean-Louis Barrat},
  journal={Physical review letters},
  year={2014},
  volume={113 24},
  pages={
          248301
        }
}
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… 
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