RELAXATION PHENOMENA IN SELF-ASSEMBLED SYSTEMS

A dynamical model is proposed to study the evolution of the structure factor in the isotropic phase of a frustrated spin model. The study has application to the development of structure in bicontinuous microemulsions. We consider both non-conserved order parameters (NCOP) and the conserved order parameters (COP). In the former case (NCOP), within a self-consistent meanfield theory, we find that in the asymptotic limit (t --> infinity) all modes of the structure factor decay with the same characteristic time. This characteristic time scales with the two fundamental lengths d and xi is present in self-assembled systems such as frustrated magnetic systems and binary alloys. In the latter case (COP), we find that no characteristic time is present within self-consistent mean-field theory and all modes decay algebraically. This is reminiscent of the long time tails in the velocity-velocity autocorrelation function observed for simple fluids.