掺Bi钨酸镉单晶体的坩埚下降法生长及近红外发光特性  

Near-Infrared Emission of Bi-Doped CdWO_4 Crystals Grown by Bridgman Method

作　　者：虞灿[1] 夏海平[1] 罗彩香[1] 胡元[1] 陈红兵[2] 徐军[3] 

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]宁波大学材料与化学工程学院,浙江宁波315211 [3]中国科学院上海硅酸盐研究所,上海200050

出　　处：《中国激光》2010年第10期2610-2614,共5页Chinese Journal of Lasers

基　　金：国家自然科学基金(50972061);浙江省杰出青年科学自然基金(R4100364);宁波市科技局(2009A610007);宁波大学王宽诚幸福基金资助课题

摘　　要：采用坩埚下降法,成功地生长出了尺寸达25 mm×100 mm,Bi2O3初始掺杂摩尔分数为0.5%的CdWO4单晶。生长初期下部晶体呈青黄色,而生长后期晶体的颜色则显血红色。在808 nm与980 nm光激发下,观察到弱的1396～1550 nm(中心波长为1504 nm)与较强的1037～1274 nm(中心波长为1078 nm)波段的近红外宽带发光,并测定其荧光寿命分别为238μs和294μs。从生长初期的青黄色到生长后期的血红色晶体,1504 nm波段的荧光强度逐步增强,而1078 nm波段的荧光强度逐步减弱。根据实验结果初步探讨了红外宽带发光的机理和起因,1078 nm波段的荧光发射与Bi离子的掺杂有密切关系,而弱的1504 nm荧光发射可能与晶体中的杂质或掺杂后形成的缺陷等因素有关。The CdWO4 crystals with good quality in the size of 25 mm×100 mm,doped Bi2O3 in 0.5 % molar fraction in the raw composition were grown by the bridgman method.The lower part of crystal which was grown at the initial stage appears yellow-green color,while the upper part of crystal blood-red color at final stage.The absorption spectra were recorded.The emission spectra of various parts of crystal were investigated when excited by 808 nm and 980 nm.The weak emission band at 1396～1550 nm（centered at 1504 nm） and strong band at 1037～1274 nm（centered at 1078 nm）were observed,and their lifetime were 238 μs and 294 μs,respectively.The emission intensity at 1504 nm increased as the growth direction,while the intensity at 1078 nm reduced as the growth direction.The mechanism for the band emission were discussed from the obtained spectra.The emission band at 1078 nm was probable related to Bi ion,while the weak band at 1504 nm was probable related to the defects of the crystal.

关 键 词：材料 CdWO4单晶 坩埚下降法 近红外宽带发光 

分 类 号：O782[理学—晶体学] O734