title: Observation of a topological relaxation mode in microemulsions.
abstract: We report the observation of two diffusive relaxation modes in a very swollen microemulsion, measured by quasielastic light scattering experiments. In addition to a short-time diffusion process, we observe a long-time diffusive relaxation mode with unusual scaling behavior: the diffusion constant D is an exponential function of the characteristic length scale xi, D~exp(-xi). This observation provides experimental evidence for thermally activated topological relaxation of random fluid phases, as predicted by Milner et al. [J. Phys. (Paris) 51, 2629 (1990)]. We describe the activation energy of such a process by some simple microscopic model for the surfactant layer and give an estimation of the membrane elastic and Gaussian moduli kappa and kappa;, and its spontaneous curvature.
authors.affiliation: Centre de Recherche Paul-Pascal, CNRS, Avenue du Dr.-Schweitzer, 33600 Pessac, France.
authors.forename: U
authors.initials: U
authors.lastname: Peter
authors.forename: D
authors.initials: D
authors.lastname: Roux
authors.forename: A K
authors.initials: AK
authors.lastname: Sood