Design of a High Thermal Expansion Coefficient, High Glass Transition Temperature Glass for Fiber Optic Use
Open Access
Author:
Mathewson, Carly
Graduate Program:
Materials Science and Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
March 02, 2020
Committee Members:
Venkatraman Gopalan, Thesis Advisor/Co-Advisor John C Mauro, Thesis Advisor/Co-Advisor Lauren Dell Zarzar, Committee Member John C Mauro, Program Head/Chair
Keywords:
Coefficient of thermal expansion Glass transition temperature aluminosilicate glass composition fiber laser
Abstract:
In this thesis, a novel glass composition is developed with properties tailored for use as a glass cladding which can endure high temperature post-processing of a ZnSe core fiber laser. Previously, post-processing of a ZnSe fiber laser resulted in cracking of the core or softening of the core/cladding interface. For this reason, several novel glasses with a coefficient of thermal expansion (CTE) similar to that of ZnSe (7.1ppm/°C) and a high glass transition temperature (Tg) of at least 750°C were designed. The structure-composition relationships considered in the making of these fibers are discussed, as is the method with which several barriers to fiber fabrication were overcome. These barriers were the result of the high processing temperatures needed to melt the glasses, which made it difficult to remove gaseous inclusions and mold the glass into a preform. The refinement of the CTE and Tg, the elimination of gaseous inclusions, and the construction of preforms are all addressed within this thesis. Additionally, it is shown that the preforms of these new glass compositions can be drawn into capillary fibers into which ZnSe is deposited and subsequently annealed without cracking of the core or softening of the core/cladding interface.
