This effort brings together an international team of glass scientists, and optical design and laser physicists to investigate advanced glasses for novel optical fiber applications. This network of scientists examines the intrinsic limits of next generation glasses for use in traditional and novel fiber geometries, models and experimentally verifies the impact of such compositional modification on the glass? hot-forming response during fiberization and extrusion, and assesses the post-fabricated material stability and optical performance of the resulting fibers. Chalcogenide and tellurite-based glasses form the primary focus of the effort, exploiting the novel aspects of the glasses visco-, thermal and optical properties.
The team addresses materials science questions which extend current capabilities in the design, processing and manufacture of advanced glasses into glass fibers. University researchers benefit from the support of key industrial partners who recognize the critical need for such advances. There is an overall benefit to the international community in bringing diverse skill sets together through global training experiences for faculty and students across a team of eight scientific groups from four countries (Australia, France, Italy and the US). Through this partnership, the US team coordinates education and research experiences for team members via summer research experiences, faculty and staff exchanges, as well as opportunities for student participants to complete dual PhD degrees.
The overarching goal of this experimental effort is to advance the fundamental understanding of the intrinsic limits of advanced optical glasses for use in traditional and novel fiber geometries. Such an advance in this research area will answer critical materials science questions, extending current capabilities to design, process and manufacture advanced glasses into glass fibers, resolve key questions on glass’ intrinsic physical properties and how they can be tailored, enhanced and optimized to allow their use in novel fiber structures. Specifically, this research focused on two glass systems for use in Infrared (IR)-transparent optical devices: chalcogenides and heavy-metal oxides. The thermal, chemical and optical properties of these glasses were measured, and used as input to Finite Element Analysis (FEA) models of the glass and the hot-forming environments. These models in turn gave a tool for the visualization of the extrusion of IR-transparent glasses into complicated shapes for drawing into novel fiber optical structures, and was used to explain phenomena such as die swell in the extruded glasses. (Figure 1) In a complimentary effort, the development of advanced heavy-metal oxide glasses for use in Raman amplification systems, was extremely successful. The goal of this effort was to maximize the amount of Raman gain achievable in tellurium-oxide glasses through engineering the glass nanostructure. Results showed that the amount of gain achievable is directly related to the number of TeO4 units in the glass network, and that the concentration of these units is directly impacted by the addition of ZnO (a common additive), which depolymerizes the tellurite glass network. (Figure 2)
