Silicon Core Optical Fibre Production and Characterisation: An investigation of alkali earth metal oxide interface additives in a fibre production method.

Abstract

Solid semiconductor optical fibres are of interest for infrared transmission and guided wave photonics. High transmission of light in the 2-6 micrometer wavelength region in optical fibres is difficult with today's materials, and the possibility of combining photonic and electronic components in one material has attracted much attention. This thesis presents a method of improving the quality of solid silicon core optical fibres made in a rapid draw process. It does this by the introduction of a alkali earth metal oxide interface modifier between the silica and the silcon core. This modifier acts as an in situ oxygen and metallic impurity getter. These investigations indicate that the interface layer forms a eutectic that reduces the stress caused by the expansion of silicon upon freezing. The silicon fibres made with this interface layer have greater mechanical flexibility than those without, but the optical losses are comparable to fibres made by other methods.