Phase separation and transformation of binary immiscible systems in molten core-derived optical fibers

This work studies phase-separated fibers in the CaO-SiO2 and NiO-SiO2 systems. The nature of the phase-separated microstructures and underlying phase equilibria are discussed, including dimensionality, composition, and phase formation as well as the realization of ferrimagnetic behavior in the NiO-SiO2 fibers based on the formation of metallic Ni inclusions. In addition to understanding the composition/processing relationships in these systems, the work represents a step forward toward novel magneto-optic fibers. It is important to understand the underlying materials science in order to advance the properties of novel optical fibers possessing engineered heterogeneities in the core.