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arXiv · cond-mat/0603739

Origin of the slow dynamics and the aging of a soft glass

Sylvain Mazoyer·Luca Cipelletti·Laurence Ramos
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Abstract

We study by light microscopy a soft glass consisting of a compact arrangement of polydisperse elastic spheres. We show that its slow and non-stationary dynamics results from the unavoidable small fluctuations of temperature, which induce intermittent local mechanical shear in the sample, because of thermal expansion and contraction. Temperature-induced shear provokes both reversible and irreversible rearrangements whose amplitude decreases with time, leading to an exponential slowing down of the dynamics with sample age.

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Sylvain Mazoyer, Luca Cipelletti, Laurence Ramos. 2006-12-19. Origin of the slow dynamics and the aging of a soft glass. https://doi.org/10.1103/physrevlett.97.238301

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