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Nearly-logarithmic decay in the colloidal hard-sphere system

Matthias Sperl
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Abstract

Nearly-logarithmic decay is identified in the data for the mean-squared displacement of the colloidal hard-sphere system at the liquid-glass transition [v. Megen et. al, Phys. Rev. E 58, 6073(1998)]. The solutions of mode-coupling theory for the microscopic equations of motion fit the experimental data well. Based on these equations, the nearly-logarithmic decay is explained as the equivalent of a beta-peak phenomenon, a manifestation of the critical relaxation when the coupling between of the probe variable and the density fluctuations is strong. In an asymptotic expansion, a Cole-Cole formula including corrections is derived from the microscopic equations of motion, which describes the experimental data for three decades in time.

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Matthias Sperl. 2005-02-24. Nearly-logarithmic decay in the colloidal hard-sphere system. https://doi.org/10.1103/physreve.71.060401

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