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Intrinsic aging and effective viscosity in the slow dynamics of a soft glass with tunable elasticity

Laurence Ramos·Luca Cipelletti
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Abstract

We investigate by rheology and light scattering the influence of the elastic modulus, $G_0$, on the slow dynamics and the aging of a soft glass. We show that the slow dynamics and the aging can be entirely described by the evolution of an effective viscosity, $η_{eff}$, defined as the characteristic time measured in a stress relaxation experiment times $G_0$. At all time, $η_{eff}$ is found to be independent of $G_0$, of elastic perturbations, and of the rate at which the sample is quenched in the glassy phase. We propose a simple model that links $η_{eff}$ to the internal stress built up at the fluid-to-solid transition.

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Laurence Ramos, Luca Cipelletti. 2004-11-03. Intrinsic aging and effective viscosity in the slow dynamics of a soft glass with tunable elasticity. https://doi.org/10.1103/physrevlett.94.158301

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