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arXiv · cond-mat/0608097

Dynamic particle tracking reveals the aging temperature of a colloidal glass

Ping Wang·Chaoming Song·Hernan A. Makse
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Abstract

Understanding glasses is considered to be one of the most fundamental problems in statistical physics. A theoretical approach to unravel their universal properties is to consider the validity of equilibrium concepts such as temperature and thermalization in these out-of-equilibrium systems. Here we investigate the autocorrelation and response function to monitor the aging of a colloidal glass. At equilibrium, all the observables are stationary while in the out-of-equilibrium glassy state they have an explicit dependence on the age of the system. We find that the transport coefficients scale with the aging-time as a power-law, a signature of the slow relaxation. Nevertheless, our analysis reveals that the glassy system has thermalized at a constant temperature independent of the age and larger than the bath, reflecting the structural rearrangements of cage-dynamics. Furthermore, a universal scaling law is found to describe the global and local fluctuations of the observables.

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Ping Wang, Chaoming Song, Hernan A. Makse. 2006-08-04. Dynamic particle tracking reveals the aging temperature of a colloidal glass. https://doi.org/10.1038/nphys366

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