Date of Award
Doctor of Philosophy (PhD)
School of Materials Science and Engineering
This research studies and yields new understandings into the materials science and engineering of advanced multicomponent glass systems, which is critical for next generation fiber lasers operating at high output powers. This begins with the study and development of Yb-doped glasses in the Al2O3-P2O5-SiO2 (APS) ternary system, fabricated using modified chemical vapor deposition (MCVD), that, despite being highly doped, possess an average refractive index matched to that of silica (SiO2). The highly doped active core material was subsequently processed through a multiple stack-and-draw process to realize a single fiber with high doping, compositionally-tailored index, and scalability for fiber lasers. Based on the knowledge gained in this first focal area, further strategic compositional tailoring to influence the glass’ photoelastic and thermo-optic coefficient, was performed in order to understand and realize significant decreases in Brillouin and thermal-Rayleigh scattering, which instigate parasitic stimulated Brillouin scattering (SBS) and transverse mode instabilities (TMI) in high power fiber lasers. In addition to understanding the composition / structure / properties of these glasses, a double-clad fiber laser will be fabricated, scaled to over 1 kW of output laser power, and studied in order to relate the materials science and engineering of multiple glass systems and fibers designs to laser performance and properties.
Hawkins, Thomas Wade, "The Materials Science and Engineering of Advanced YB-Doped Glasses and Fibers for High-Power Lasers" (2020). All Dissertations. 2585.