高均匀性高掺镁铌酸锂晶体的生长与表征  

Growth and Characterization of High Homogeneity Heavily MgO-doped Lithium Niobate Crystals

作　　者：涂小牛[1] 郑燕青[1] 陈辉[1] 孔海宽[1] 忻隽[1] 曾一明[1] 施尔畏[1] 

机构地区：[1]中国科学院上海硅酸盐研究所,上海201800

出　　处：《无机材料学报》2010年第12期1257-1262,共6页Journal of Inorganic Materials

基　　金：中科院知识创新工程重要方向项目(KGCX-2-YW-206);国家863计划(2006AA03Z423);中科院重大科研装备研制项目(YZ200934)~~

摘　　要：采用提拉法生长了高掺镁铌酸锂晶体,并采用高温极化法使晶体单畴化.为研究晶体的成分均匀性、光学均匀性及铁电畴均匀件,采用光谱、激光干涉、电子探针、显微观察等表征手段测定与观察了晶体的紫外吸收边、OH吸收峰、折射率梯度△n、晶体径向上的微观成分及晶体的铁电畴结构.结果表明:通过采用合适的生长组分和改进提拉法生长工艺获得了高质量的高掺镁铌酸锂晶体.晶体的紫外吸收边位于308 nm附近,OH吸收峰位于高抗光损伤阈值特征峰2828 nm处,光学均匀性达△n<5.11×10^(-5).在1200℃下通过外加电场极化获得了高均匀性且完全单畴的铁电畴结构.High homogeneity heavily MgO-doped lithium niobate （MgLN for short） single crystals were grown by Czochralski method. The as-grown crystals were poled at high temperature, so as to obtain single ferroelectric domain structure. UV absorption edge, OH absorption peak, optical homogeneity of the crystal were tested, respectively. Micro- compositions along the radial direction were analyzed by EDS method and ＂line scan＂ of the distribution of Mg element along the radial direction was investigated by WDS method. The results showed that high homogeneity MgLN crystals were obtained with proper starting composition and improved growth process of Czochralski technology. UV ab- sorption edge at 308 um and OH absorption peak at 2828 nm were observed. The optical homogeneity △ n〈5.11× 10^-5. Finally, ferroelectric domain structure was observed by optical microscope by chemical etching method. High uniformity single ferroelectric domain structure was obtained by applying an external electric field at 1200℃.

关 键 词：高掺镁铌酸锂晶体 紫外吸收边 OH吸收峰 畴结构 光学均匀性 

分 类 号：O78[理学—晶体学] O73