在LiNbO_3:Fe晶体中暗辐照对光束从自散焦向自聚焦转换过程的影响  

Influence of dark irradiation on transition process from self- defocusing to self-focusing in LiNbO_3:Fe crystals

作　　者：黄春福[1] 郭儒[1] 刘思敏[1] 舒强[1] 高垣梅[1] 汪大云[1] 刘照红[1] 张小华[1] 陆猗[2] 

机构地区：[1]南开大学物理学院,天津300071 [2]天津理工学院自动化系,天津300071

出　　处：《物理学报》2004年第5期1367-1372,共6页Acta Physica Sinica

基　　金：国家自然科学基金 (批准号 :60 2 780 0 6和 60 3 780 13 )资助的课题~~

摘　　要：基于二维带输运模型 ,研究了LiNbO3:Fe晶体中光束从自散焦向自聚焦动态转换过程 .结果表明暗辐照在动态转换过程中起着非常重要的作用 ,当暗辐照较小时动态转换过程才发生 .在暗辐照较小的情况还分析了热释电效应对动态转换过程的影响 .We have studied the dynamic propagation of an optical beam from self-defocusing to self-focusing in photovoltaic photorefractive crystals LiNbO 3:Fe in the framework of a two-dimensional band transport model. The results show that dark irradiation plays an important part in the transition process. The transition occurs only when the normalized dark irradiation is very small. We discuss also the influence of pyroelectric effect on the transition process.

关 键 词：光生伏打效应 暗辐照 自散焦 自聚焦 铌酸锂晶体 铁掺杂 

分 类 号：O437[机械工程—光学工程]