A novel approach to the formation of photonic structures in glasses

Summary form only given. Both natural and artificial structures consisting of particles with size in the optical wavelength range are of interest since their optical properties can be controlled by choosing a suitable type, size and mutual disposition of these particles, when formed in solids. We present a novel approach to form such structures. This approach is based on a liquid-liquid phase separation of glasses resulting in the formation of glassy microspheres with a narrow size distribution and their index different from that of the glassy matrix into which they are embedded. The flexibility of glass compositions and the possibility to vary and to control the size and composition of those microspheres by thermal temporal conditions make this approach a promising one for the formation of photonic structures, e.g., microresonators.