Microstructured tellurite glass fibre laser development.

Abstract

This thesis contains a study of the suitability of tellurite glass for use in microstructured fibre lasers. This thesis looks into the possibility for lasing at around 3μm, where tellurite glass is transparent. To test the lasing potential of fabricated tellurite glass microstructured fibres, lasing at 1.5μm was demonstrated. The research contained within this thesis includes: The development and characterisation of the tellurite glass composition; including modifications made to this composition to match the refractive indices of the doped and undoped glasses, reducing the glass material loss, finding the glass crystallisation stability and density as well as measuring the temperature dependence of the glass melt viscosity, of which an understanding is required for its extrusion (Chapter 2). The fabrication of microstructured tellurite fibres which included large mode area fibres, motivated by the desire to fabricate a double clad fibre and the development of small core fibres which were used in the fibre laser experiments (Chapter 3). A spectroscopic study of the erbium III doped glass including lifetimes, absorption and emission measurements (Chapter 4) and a description of the laser modelling, experiments and results (Chapter 5).