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).

Upconversion luminescence from E-2 state of Cr3+ in Al2O3 crystal by infrared femtosecond laser irradiation

Visible upconversion luminescence was observed in Cr3+: Al2O3 crystal under focused femtosecond laser irradiation. The luminescence spectra show that the upconversion luminescence originates from the E-2-(4)A(2) transition of Cr3+. The dependence of the fluorescence intensity of Cr3+ on the pump power reveals that a two-photon absorption process dominates in the conversion of infrared radiation to the visible emission. It is suggested that the simultaneous absorption of two infrared photons produces the population of upper excited states, which leads to the characteristic visible emission from E-2 state of Cr3+.

Broadband infrared luminescence from Li2O-Al2O3-ZnO-SiO2 glasses doped with Bi2O3

The broadband emission in the 1.2 similar to 1.6 mu m region from Li2O-Al2O3-ZnO-SiO2 ( LAZS) glass codoped with 0.01mol.% Cr2O3 and 1.0mol.% Bi2O3 when pumped by the 808nm laser at room temperature is not initiated from Cr4+ ions, but from bismuth, which is remarkably different from the results reported by Batchelor et al. The broad similar to 1300nm emission from Bi2O3-containing LAZS glasses possesses a FWHM ( Full Width at Half Maximum) more than 250nm and a fluorescent lifetime longer than 500 mu s when excited by the 808nm laser. These glasses might have the potential applications in the broadly tunable lasers and the broadband fiber amplifiers. (c) 2005 Optical Society of America.

Cr^3＋：Al2O3透明多晶陶瓷光谱特性分析

对透光性良好的Cr^3＋：Al2O3透明多晶陶瓷的光谱性能进行了研究，其吸收光谱中吸收峰与单晶红宝石相一致，按吸收光谱和Tanabe-Sugano能级图，算出其晶场强度参数Dq及Racah参数B分别为1792cm^-1，689cm^-1，Dq／B=2．6，陶瓷中Cr^3＋离子所处格位的晶体场强比单晶弱一些，但Cr^3＋：Al2O3透明陶瓷仍属于强场晶体材料；当Cr^3＋掺杂浓度到达0．8wt％时，陶瓷的发射谱仍保持较好的R线发射；随Cr^3＋掺杂浓度的增大，激发峰位发生“红移”．在Cr^3＋：Al2O3透

Mg，Ti共掺Al2O3透明多晶陶瓷光谱性能研究

Transparent polycrystalline MgO and TiO2 codoped Al2O3 ceramics were fabricated by conventional solid-state pressureless processing. The absorption, emission and excitation spectra of ( Mg, Ti : Al2O3 ceramics were measured. Owing to charge compensation of Mg2+, only UV absorption around 250nm was observed due to O2- -> Ti4+ charge transfer transitions (CT) when Ti content was low. As a result, the emission peaks of isolated Ti4+ ion located at 280-290nm and 410-420nm were observed. Besides absorption peak of V, ion, the characteristic absorption peak of V, ion centered at 490nm was observed in Mg, Ti) : Al2O3 ceramics when Ti content was high. The emission spectra of Ti3+, ion in polycrystalline Al2O3 ceramics coincide with that of Ti: Al2O3 single crystal.

Cr4+在Al2O3多晶体中的光谱性能研究

Transparent polycrystalline Cr:Al2O3 ceramics were synthesized by conventional pressureless synthesis processing. The absorption and emission spectra of Cr:Al2O3 ceramics specimens before and after annealing were measured at room temperature. It was discovered that the emission spectra of Cr4+ in Al2O3 octahedral coordination site is in infrared wavelength range of 1100-1600 nm. The emission peak of Cr4+ is centered at 1223 nm, which is similar to that of Cr4+ in tetrahedral site. Al2O3 has smaller lattice constant, resulting in the larger crystal field strength, so there is a blue shift in the peak of Cr4+:Al2O3 ceramics compared to those of other Cr4+-doped crystals. And the emission band is much narrower with full width at half maximum Delta lambda 37 nm.

VTE法制备γ-LiAlO2／α-Al2O3复合衬底以及腐蚀和退火对其影响

通过气相传输平衡法(VTE)制备了γ-LiAlO2／α-Al2O3复合衬底，使用5％的稀盐酸对其进行腐蚀并在900℃退火72h。利用X射线衍射、偏光显微镜及扫描电镜对复合衬底进行了分析，发现在白宝石α面(11-20)和γ面(1—102)均获得单相多晶的γ-LiAlO2，且后者的择优取向好于前者。腐蚀可以提高样品的择优取向，在5％的稀盐酸中，时间控制在2min左右可获得较好的结果。退火后γ-LiAlO2颗粒质量得到改善，白宝石α面上γ-LiAlO2的质量优于r面上的γ-LiAlO2，两者都出现颗粒长大现象。

温梯法生长的Ti：Al2O3晶体的光谱分析

本文研究了不同掺Ti^3＋浓度对温梯法生长的Ti：Al2O3晶体吸收光谱、荧光光谱和X射线衍射光谱的影响。根据吸收光谱提出了一个色心模型。对比了样品各处420nm荧光谱，发现掺Ti^3＋浓度越大，该处荧光强度越弱，同时解释了420肿处荧光峰的起源。对比了样品各处720nm处的荧光谱，发现掺Ti^3＋浓度越大，该处荧光强度越强。X射线衍射谱（XRD）表明，衍射峰强度随掺Ti^3＋浓度的增大而逐渐增强。

Ti：Al2O3透明多晶陶瓷光谱特性分析

采用传统无压烧结工艺制备出透明性良好的掺Ti氧化铝陶瓷；测定了该陶瓷的吸收光谱、荧光光谱和激发光谱。结果表明，掺Ti氧化铝透明陶瓷样品在Mg与Ti掺入离子的摩尔比（NMg／NTi）较小时，表现出Ti^3＋离子的490nm特征吸收峰，即^2T2→^2E跃迁产生的宽带吸收；NMg／NTi较大时，陶瓷样品吸收光谱中不存在Ti^3＋离子吸收，其250nm处吸收为O^2-→Ti^4＋的转移吸收。掺Ti氧化铝透明陶瓷样品Ti^3＋离子的发射谱线与单晶的相吻合，同时Ti^3＋在氧化铝陶瓷中分布很均匀，且Ti^3＋浓度较

Al2O3衬底上生长ZnO薄膜的结构和光学特性

用脉冲激光沉积法在Al2O3（0001）衬底上沉积了ZnO薄膜。衬底温度分别为300℃、400℃、500℃、600℃和700℃。利用X射线衍射（XRD）和光致发光谱（PL）对薄膜的结构和光学性能进行研究。X射线衍射的结果表明在不同温度下生长的ZnO薄膜均具有高度c轴择优取向，衬底温度400℃时，膜的应力较小质量较高。ZnO薄膜有很强的紫外发光峰，紫外发光峰的强度与衬底温度密切相关，并发现当衬底温度从300℃增到400℃时，紫外发射峰出现6nm的蓝移。