Fabrication and characterization of Cr:forsterite single crystal fiber

Cr:forsterite (Cr:Mg 2 SiO 4 ) single crystal fibers of diameter less than 100 μm were made for the first time to our knowledge. This novel fiber material will be used to make fiber light sources such as fiber lasers and broadband light sources for applications in biophotonics and optical communications. Cr:forsterite crystal has a broad emission spectrum ranging from 1.1 to 1.4 μm that traditional glass fibers or semiconductor light sources cannot offer. And fiber light sources are compact, efficient, maintenance-free and compatible with fiber-optic components potentially leading to new performance and functions. In this work, bulk Cr:forsterite crystal was melted, pulled and re-grown into a long fiber using laser heated pedestal growth (LHPG) technique. Single crystal rhombic structure was preserved and verified by Xray diffractometer. By using electron probe micro-analyzer, change in Cr dopant concentration and distribution profile for various fiber diameters and growth conditions was studied.