A study was made of the aging of a colloidal laponite glass by measuring the dynamic structure factor of dilute embedded tracer particles at μm length-scales. It was shown that an initial aging regime, where the decay-time grew exponentially with aging time, tw, τ ~ exp(γtw), was followed by a full aging regime, τ ~ twv, with v ≈ 1. The dynamics of the tracers were diffusive in the exponential regime, and hyper-diffusive in the full aging regime; up to μm length-scales.

Successive Exponential and Full Aging Regimes Evidenced by Tracer Diffusion in a Colloidal Glass. S.Kaloun, R.Skouri, M.Skouri, J.P.Munch, F.Schosseler: Physical Review E, 2005, 72[1], 011403 (5pp)