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dc.contributor.advisorKasap, Safaen_US
dc.creatorOkada, Goen_US
dc.date.accessioned2010-06-30T15:20:11Zen_US
dc.date.accessioned2013-01-04T04:41:26Z
dc.date.available2011-07-08T08:00:00Zen_US
dc.date.available2013-01-04T04:41:26Z
dc.date.created2010-06en_US
dc.date.issued2010-06en_US
dc.date.submittedJune 2010en_US
dc.identifier.urihttp://hdl.handle.net/10388/etd-06302010-152011en_US
dc.description.abstractFor high-resolution X-ray imaging scintillator applications, we have prepared and optically characterized divalent samarium doped fluorochlorozirconate (FCZ:Sm2+) glasses and glass-ceramics. Sm2+ doped FCZ glasses were obtained by adding a reducing agent, NaBH4 into the initial melt to convert some of the Sm3+ to Sm2+. However, the Sm2+ concentration at most was estimated to be only approximately 0.003 %. The as-prepared glass samples were further heat treated to obtain glass-ceramics; the nucleation and growth of BaCl2 nanocrystals were confirmed by powdered X-ray diffraction (XRD) experiments. Depending on the heat treatment conditions (temperature and time), the average nanocrystal size varies from 8 to 170 nm, and the sample contains BaCl2 nanocrystals with the orthorhombic and/or hexagonal structure. The optical absorption spectra for our glass-ceramic samples suggested the substitution of Sm2+ ions into the BaCl2 lattice site. The FCZ:Sm2+ glass-ceramics samples showed strong fluorescence in the red region of spectrum (approximately 8 times that of an as-prepared glass), and the transparency can be very high (transmittance > 80 % for samples with thickness about 0.5 mm) and can be equivalent to that of an as-prepared glass . These two results promise potential as a high-resolution X-ray scintillator due to the emission wavelength range and high transparency. Extensive studies of photoluminescence (PL) spectra at low temperatures (12 -- 200 K) for FCZ:Sm2+ glass-ceramics suggested useful indicators of the crystal structure and average size of embedded BaCl2 nanocrystals. A detailed analysis of the optical spectra has lead to the identification of the origin of the emission peaks and the location of Sm ions at specific crystallographic sites. X-ray induced luminescence (XL) studies have suggested a strong dependence of the fluorescence intensity on the concentration of Sm2+ ions. In addition, for more efficient fluorescence, a sample should be heat treated in a hydrogen containing atmosphere (e.g. H2 + Ar gas), and the heat treatment conditions should be such that the nanocrystals grow in the hexagonal structure.en_US
dc.language.isoen_USen_US
dc.subjectGlass-Ceramicen_US
dc.subjectSamariumen_US
dc.subjectOptical Propertiesen_US
dc.subjectX-ray Imaging Scintillatoren_US
dc.titleOptical properties of rare-earth doped fluorozirconate glass-ceramics for x-ray detector applicationsen_US
thesis.degree.departmentElectrical Engineeringen_US
thesis.degree.disciplineElectrical Engineeringen_US
thesis.degree.grantorUniversity of Saskatchewanen_US
thesis.degree.levelMastersen_US
thesis.degree.nameMaster of Science (M.Sc.)en_US
dc.type.materialtexten_US
dc.type.genreThesisen_US
dc.contributor.committeeMemberChen, Lien_US
dc.contributor.committeeMemberYang, Qiaoqinen_US
dc.contributor.committeeMemberJohanson, Roberten_US


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