Aging behavior of the localization length in a colloidal glass

TL;DR

This study investigates how the localization length in a colloidal glass evolves with aging, revealing differences between spontaneous aging and rejuvenation, and correlating these changes with mechanical properties.

Contribution

It provides a quantitative analysis of the aging behavior of localization length in colloidal glasses using XPCS, highlighting differences between aging processes and linking to rheological properties.

Findings

Localization length varies with aging in colloidal glass.

Differences observed between spontaneous aging and rejuvenation.

Shear modulus correlates with localization length changes.

Abstract

The localization length r_{loc} associated with a fast secondary relaxation in glassy Laponite is determined by X-ray photon correlation spectroscopy (XPCS) through a Debye-Waller fit of the non-ergodicity parameter. Quantitative differences are observed between the time dependence (aging) of r_{loc} in spontaneously aged and rejuvenated samples. This behavior is also reflected in the calculated shear modulus which matches well with data obtained by rheological measurements.