Curvature distributions of spinodal interface in a condensed matter system

The time evolution of a three-dimensional spatially bicontinuous interface of a phase-separated polymer blend, as a model of condensed matter systems, in late stage spinodal decomposition (SD) has been studied by laser scanning confocal microscopy. Probability densities of the mean and the Gaussian curvatures of the interface have been obtained. The probability densities of the curvatures at various times were successfully scaled by a characteristic length, which confirms the validity of the dynamical scaling law. We found that a large portion of the interface formed in late stage SD consists of saddle-shaped surfaces.