Effect of controlling recrystallization from the melt on the residual stress and structural properties of the Silica-clad Ge core fiber.

Effect of controlling recrystallization from the melt (1000 °C) on the residual stress and structural properties of a Ge core fiber via molten core drawing (MCD) method is investigated. Ge core fibers is investigated using Raman spectroscopy, scanning electron microscope (SEM), and X-ray diffraction (XRD). Compared with the as-drawn Ge fiber, the Raman peak of the recrystallized Ge fiber shift from 300 cm −1 to 300.6 cm −1 and full width at half maximum (FWHM) decreased from 5.36 cm −1 to 4.48 cm −1 . The Ge crystal grains which sizes are of 200–600 nm were formed during the process of recrystallization; the XRD peak of (1 1 1) plane is observed after recrystallization. These results show that controlling recrystallization allows the release of the thermal stress, and improvement of the crystal quality of Ge core. [ABSTRACT FROM AUTHOR]