Transparent Ni2+-doped ZnO-Al2O3-SiO2 system glass-ceramics with broadband infrared luminescence

We report transparent Ni2+-doped ZnO-Al2O3-SiO2 system glass-ceramics with broadband infrared luminescence. After heat-treatment, ZnAl2O4 crystallite was precipitated in the glasses, and its average size increased with increasing heat-treatment temperature. No infrared emission was detected in the as-prepared glass samples, while broadband infrared luminescence centered at 1310 nm with full width at half maximum (FWHM) of about 300 nm was observed from the glass-ceramics. The peak position of the infrared luminescence showed a blue-shift with increasing heat-treatment temperature, but a red-shift with an increase in NiO concentration. The mechanisms of the observed phenomena were discussed. These glass-ceramics are promising as materials for super broadband optical amplifier and tunable laser. (c) 2006 Elsevier Ltd. All rights reserved.

Ni^2＋掺杂透明ZnO-Al2O3-SiO2系微晶玻璃的光学性质

采用传统熔融冷却的方法制备了透明Ni^2＋掺杂ZnO-Al2O3-SiO2系玻璃，结合X-射线、吸收和荧光等测试手段，研究了不同热处理温度对Ni^2＋掺杂透明ZnO-Al2O3-SiO2系微晶玻璃光学性质的影响。由X-射线衍射谱鉴定出微晶玻璃中析出的晶相为ZnAl2O4微晶，其尺寸在13nm以下。玻璃中没有发现近红外发光，而在微晶玻璃中存在宽带近红外发光，其可归属为八面体六配位Ni^2＋离子的^3T2g（^3F）激发态向^3A2g（^3F）基态的跃迁。随热处理温度升高发光强度增强，而发射峰位则发生蓝移；荧

Influence of thermal annealing on optical properties and surface morphology of NiOx thin films

NiOx thin films were deposited by reactive DC-magnetron sputtering from a nickel metal target in Ar + O-2 with the relative O-2 content of 5%. Thermal annealing effects on optical properties and surface morphology of NiOx, films were investigated by X-ray photoelectron spectroscopy, thermogravimetric analysis, scanning electron microscope and optical measurement. The results showed that the changes in optical properties and surface morphology depended on the temperature. The surface morphology of the films changed obviously as the annealing temperature increased due to the reaction NiOx -> NiO + O-2 releasing O-2. The surface morphology change was responsible for the variation of the optical properties of the films. The optical contrast between the as-deposited films and 400 degrees C annealed films was about 52%. In addition, the relationship of the optical energy band gap with the variation of annealing temperature was studied. (c) 2006 Elsevier B.V. All rights reserved.

P2O5-B2O3-R2O-MO-Al2O3系统玻璃物化性质的研究

以Yb^3+-Er^3+共掺的P2O5-B2O3-R2O-MO-Al2O3(R=Li，Na，K；M=Zn，Ca，Sr，Ba)系统玻璃为研究对象，分别分析了改变B2O3，的含量，以及加入不同种类的碱金属和碱土金属氧化物对玻璃的物理化学性质的影响。研究结果表明，当B2O3的含量增加，玻璃的Tg，Tf上升，热膨胀系数下降；随着修饰体阳离子半径减小，玻璃的溶解速率下降，化学稳定性变好。

Al2O3,B2O3对磷酸盐包边玻璃形成区和物化性质影响研究

研究了Al2O3 ,B2O3对P2O5-Al2O3-B2O3-ZnO-Na2O-CuCl玻璃形成区的影响规律；包边玻璃的物化性质随B/(B+Al)的变化规律；以及特定组分包边玻璃的透射光谱和吸收系数。这些研究工作对高功率大尺寸钕磷酸盐激光包边玻璃的研制具有非常重要的意义。

Physical and thermal properties of P2O5-Al2O3-BaO-La2O3 glasses

The physical and thermal properties Of P2O5-Al2O3-BaO-La2O3 glasses were investigated. The effects of glass compositions on the transition temperature, thermal expansion coefficient, density, hardness and refractive index of glasses were studied. The highest hardness of the glasses is 4143.891 MPa and the lowest thermal expansion coefficient of the glasses is 71.770 x 10(-7)/° C. A phosphate glass with high mechanical strength and good thermal characteristic is obtained.

Transparent Ni2+-doped MgO-Al2O3-SiO2 glass ceramics with broadband infrared luminescence

We report on transparent Ni2+-doped MgO-Al2O3-SiO2 glass ceramics with broadband infrared luminescence. Ni2+-doped MgO-Al2O3-SiO2 glass is Prepared by using the conventional method. After heat treatment at high temperature, MgAl2O4 crystallites are precipitated, and their average size is about 4.3nm. No luminescence is detected in the as-prepared glass sample, while broadband infrared luminescence centred at around 1315nm with full width at half maximum (FWHM) of about 300nm is observed from the glass ceramics. The observed infrared emission could be attributed to the T-3(2g)(F-3) -> (3)A(2g)(F-3) transition of octahedral Ni2+ ions in the MgAl2O4 crystallites of the transparent glass ceramics. The product of the fluorescence lifetime and the stimulated emission cross section is about 1.6 X 10(-24) s cm(2).

Effects of annealing on the color, absorption spectra, and light yield of Ce : YAlO3 single crystal grown by the temperature gradient technique

YAlO3 single crystal doped with Ce3+ at concentration 1% was grown by the temperature gradient technique. The as-grown crystal was pink. After H-2 annealing or air annealing at 1400degreesC for 20 h, the crystal was turned into colorless. We concluded there were two kinds of color centers in the as-grown crystal. One is F+ center attributed to absorption band peaking at about 530 nm, the other is O- center attributed to absorption band peaking at about 390 nm. This color centers model can be applied in explaining the experiment phenomena including the color changes, the absorption spectra changes, and the light yield changes of Ce:YAP crystals before and after annealing. (C) 2004 American Institute of Physics.