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arXiv · 2308.14425

Dichotomic Aging Behaviour in a Colloidal Glass

Roberta Angelini·Laura Zulian·Andrei Fluerasu·Anders Madsen·Giancarlo Ruocco·Barbara Ruzicka
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Abstract

An unexpected dichotomic long time aging behaviour is observed in a glassy colloidal clay suspension investigated by X-Ray Photon Correlation Spectroscopy and Dynamic Light Scattering. In the long time aging regime the intensity autocorrelations are non-exponential, following the Kohlrausch-Williams-Watts functional form with exponent bQ. We show that for spontaneously aged samples a stretched behaviour (\beta_Q < 1) is always found. Surprisingly a compressed exponent (\beta_Q > 1) appears only when the system is rejuvenated by application of a shear field. In both cases the relaxation times scale as Q^{-1}. These observations shed light on the origin of compressed exponential behaviour and helps in classifying previous results in the literature on anomalous dynamics.

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Roberta Angelini, Laura Zulian, Andrei Fluerasu, Anders Madsen, Giancarlo Ruocco, Barbara Ruzicka. 2023-08-28. Dichotomic Aging Behaviour in a Colloidal Glass. https://doi.org/10.1039/c3sm52173g

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