Probing heterogeneous dynamics of a repulsive colloidal glass by time resolved x-ray correlation spectroscopy

摘要

We present here experimental results obtained by time resolved x-ray correlation spectroscopy, revealing the heterogeneous nature of the dynamics down to the nanoscale in a dense dispersion of magnetic nanoparticles. The dynamical susceptibility, which quantifies the amplitude of the dynamical fluctuations, is investigated in a repulsive colloidal glass. Its value is an order of magnitude smaller than the ones found in gels and is length scale independent in the Q-range of the x-ray scattering experiment.