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arXiv · cond-mat/0109105

Ultraslow dynamics and stress relaxation in the aging of a soft glassy system

Laurence Ramos·Luca Cipelletti
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Abstract

We use linear rheology and multispeckle dynamic light scattering (MDLS) to investigate the aging of a gel composed of multilamellar vesicles. Light scattering data indicate rearrangement of the gel through an unusual ultraslow ballistic motion. A dramatic slowdown of the dynamics with sample age $t_{w}$ is observed for both rheology and MDLS, the characteristic relaxation time scaling as $t_{w}^μ$. We find the same aging exponent $μ=0.78$ for both techniques, suggesting that they probe similar physical processes, that is the relaxation of applied or internal stresses for rheology or MDLS, respectively. A simple phenomenological model is developed to account for the observed dynamics.

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Laurence Ramos, Luca Cipelletti. 2001-09-06. Ultraslow dynamics and stress relaxation in the aging of a soft glassy system. https://doi.org/10.1103/physrevlett.87.245503

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