Transparent ceramics are an important class of optical materials with applications in high-strength windows, radiation detectors and high-power lasers. Despite the many successful developments of the past decades, their challenging fabrication still needs to be perfected to achieve a better consistency in optical quality. In particular, ternary phase materials such as Yttrium Aluminum Garnet (YAG, Y3Al5O12), a long standing high-power laser host, require a precise control of stoichiometry, often beyond the precision of current analytical techniques, in order to reduce scattering losses and the presence of deleterious point defects. This work explores the potential of Laser-Induced Breakdown Spectroscopy (LIBS) for the quantitative analysis of ceramic compositions near stoichiometry. We have designed a compact and automated LIBS system to determine the plasma composition of sintered mixtures of Y2O3-Al2O3 near the garnet composition. The performance of our setup is evaluated and compared to conventional techniques. Optimized conditions for the acquisition of plasma emission spectra are discussed and the intensity ratios of Y+ and Al in the 300 to 400nm spectral range are analyzed using simple plasma models. The results show that, for the selected parameters of our experiments, the fluctuations in plasma temperature are minimal, and the stability of the plasma is improved. Current results show that ceramic compositions can be resolved within 1 at% in oxide and several suggestions are proposed to further increase the accuracy and precision of the method.
Master of Science (M.S.)
College of Optics and Photonics
Optics and Photonics
Optics and Photonics
Length of Campus-only Access
Masters Thesis (Open Access)
Dissertations, Academic -- Optics and Photonics; Optics and Photonics -- Dissertations, Academic
Kazemi, Jahromi, Ali, "Highly-Sensitive Stoichiometric Analysis of YAG Ceramics Using Laser-Induced Breakdown Spectroscopy (LIBS)" (2014). Electronic Theses and Dissertations. 4507.