γ射线辐照与O_2退火对Bi∶CdWO_4单晶体光谱性能的影响  

Effects of γ Irradiation and O_2-Annealing on Optical Spectra of Bi Doped Cadmium Tungstate Crystal

作　　者：罗彩香[1] 夏海平[1] 虞灿[1] 张约品[1] 徐军[2] 

机构地区：[1]宁波大学光电子功能材料重点实验室,浙江宁波315211 [2]中国科学院上海硅酸盐研究所,上海200050

出　　处：《光谱学与光谱分析》2012年第6期1476-1479,共4页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(50972061);浙江省自然科学基金项目(R4100364;Z4110072);宁波市自然科学基金项目(2009A610007);宁波大学王宽诚幸福基金项目资助

摘　　要：用500和800℃,在氧气下,对掺Bi钨酸镉晶体进行热退火处理,测定了处理后晶体的吸收光谱与发射光谱。随退火处理温度的升高晶体的吸收强度降低,吸收边带发生蓝移。在373与980nm的光激发下,分别观察到发光中心为528nm的CdWO4晶体本征发光与发光中心为1 078nm的Bi 5+发光。晶体样品通过高温氧气处理,发光中心为528nm的荧光带强度增强,但发光中心为1 078nm的荧光带强度变弱。这可能是由于氧退火使Bi 5+转化成Bi 3+所致。经退火处理后,晶体的颜色逐渐变浅,透光率明显提高,这是由于晶体中氧空位减少所致。经γ射线辐照处理后,528nm处的发光增强,而1 078nm处的发光减弱,这可能是由于γ射线辐照后导致Bi 5+变成Bi 3+。The Bi doped tungstate of cadmium crystals were O2-annealed at various temperature,and the absorption and emission spectra of O2-annealed Bi doped tungstate of cadmium crystals were investigated.The absorption intensity decreased,and the absorption side band was shifted to blue short wavelength as the increase of annealing temperature.The emissions at 528 nm and 1 078 nm were observed under excited by 373 and 980 nm,which they were attributed to the intrinsic emission of CdWO4 crystal and emission of Bi5＋ ion,respectively.After the crystals were O2-annealed,the 528 nm emission intensity enhanced while the 1 078 nm intensity reduced.It was attributed to the transformation of Bi5＋ to Bi3＋ ions in the annealing process.After O2-annealed,the transmission of the crystal was enhanced obviously and the color of the crystal became weak.It is attributed to the decrease of oxygen vacancy（Vo） in crystal after the crystal was heated in O2 atmosphere.The 1 078 nm emission intensity reduced while the 528 nm intensity enhanced after the crystals were γ-irradiated.It may be due to the transormation of Bi5＋ to Bi3＋ ions through evolution of γ-irradiated.

关 键 词：O2退火 Γ射线 光谱 Bi离子 

分 类 号：O78[理学—晶体学]