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Abstract: The near infrared spectroscopic properties of Tm3+−Yb3+ co-doped tellurite glasses were investigated using a 980nm laser diode. The 1.81μm emission corresponding to the 3F4→3H6 transition of Tm3+ and the 1.02μm emission of Yb3+ were recorded at room temperature. The effects of Tm3+ and Yb3+ ion concentrations on the emission characteristics and the lifetimes of 1.81μm and 1.02μm were also analyzed. These results indicate that the energy transfer occurred between the Yb3+ and Tm3+ ions in the co-doped tellurite glasses. The luminescence mechanism in Yb3+ and Tm3+ co-doped tellurite glass was also discussed, which is important to develop 1.8μm fiber lasers or 1.8μm and 1.465μm fiber amplifiers. [Copyright &y& Elsevier]

Abstract: Relaxation of 1.54μm emission of the erbium doped borosilicate glasses with high rare earth solubility was investigated. When the erbium content is less than 0.2wt%, multi-phonon relaxation is the predominant process of non-radiative relaxation. It is difficult to increase the quantum efficiency higher than 70% for erbium ions in this glass due to multi-phonon relaxation. Because of the good glass-formation ability and high rare earth solubility, this glass will be suitable as a host for rare earth ions with a large energy gap, such as Yb3+, Eu3+ or Tb3+. [Copyright &y& Elsevier]

Abstract: A series of Bi2O3–BaO–SiO2–RxOy (designated BiBaSi glass) glass sealants doped with different contents of TiO2 were prepared by conventional melting and annealing technique. The onset of crystallization temperature was determined by differential thermal analysis. The CTEs along with transition temperature (Tg) and softening temperature (Tf) were determined from dilatometric measurement. X-ray diffraction was used to determine the crystal phases. Scanning electron microscopy was used to study the microstructure and an associated energy dispersive X-ray spectroscopy was used to study element distribution. The good matching of thermal properties and the strong adherence to the electrolyte and connector indicate that the composite glass with 7.3mol% TiO2 (BAS3) appeared to be a good candidate for SOFC sealing. [Copyright &y& Elsevier]

Abstract: Transparent Ni2+-doped SiO2-Al2O3-Ga2O3-Li2O (LGAS) glass–ceramics embedding lithium aluminate spinel nanocrystals was prepared. After heat treatment, LiAl5O8 crystallite was precipitated in the glasses, and its size was about 3nm. It was confirmed from the absorption spectra that the ligand environment of Ni2+ ions changed from the trigonal bi-pyramid fivefold sites in the as-made glass to the octahedral sites in the glass–ceramics. Upon excitation at 980nm, broadband infrared luminescence centered at around 1250nm with full width at half maximum (FWHM) more than 250nm was observed originating from the 3 T 2(3 F) → 3 A 2(3 F) transition of Ni2+ in octahedral sites. The broadband near-infrared (NIR) emission from Ni2+-doped glass–ceramics can be as host materials for broadband optical amplifier. [Copyright &y& Elsevier]