The primary and secondary relaxation timescales of aging colloidalsuspensions of Laponite are estimated from intensity autocorrelation functionsobtained in dynamic light scattering (DLS) experiments. The dynamical slowingdown of these relaxation processes are compared with observations in fragilesupercooled liquids by establishing a one-to-one mapping between the waitingtime since filtration of a Laponite suspension and the inverse of thetemperature of a supercooled liquid that is rapidly quenched towards its glasstransition temperature. New timescales, such as the Vogel time and the Kauzmanntime, are extracted to describe the phenomenon of dynamical arrest in Laponitesuspensions. In results that are strongly reminiscent of those extracted fromsupercooled liquids approaching their glass transitions, it is demonstratedthat the Vogel time calculated for each Laponite concentration is approximatelyequal to the Kauzmann time, and that a strong coupling exists between theprimary and secondary relaxation processes of aging Laponite suspensions.Furthermore, the experimental data presented here clearly demonstrates theself-similar nature of the aging dynamics of Laponite suspensions within arange of sample concentrations.
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