铌酸锂晶体中写入晶格周期与衍射效率的关系  

Relationship between writing lattice period and diffraction efficiency in lithium niobate crystals

作　　者：武一洁[1] 杨立森[1] 王龙飞[1] 李永辉[1] 逯文婷[1] 李强[1] 施慧渊[1] 

机构地区：[1]内蒙古师范大学物理与电子信息学院,内蒙古呼和浩特010022

出　　处：《光通信研究》2014年第1期49-52,共4页Study on Optical Communications

基　　金：国家自然科学基金资助项目(60467002);内蒙古自然科学基金资助项目(2013MS0926)

摘　　要：为了得到衍射效率高的光子晶格,采用光诱导光子晶格的方法,在LiNbO3∶Fe(掺铁铌酸锂)晶体中写入一维光子晶格。对写入晶格周期的密度的最小值,以及晶格周期与衍射效率之间的关系进行了研究,并对用不同波长的激光器写入时的情况进行了对比。实验结果表明,写入周期最小时为入射波长的一半,此时两束入射光形成驻波。发现双光束夹角在20°以内时衍射效率比较高,大于25°时衍射效率比较低。得出结论是:要得到衍射效率高的光子晶格,双光束夹角应在20°以内,并使用短波长激光器作为辐照光源。In order to obtain photonic lattices with high diffraction efficiency,we write a one-dimensional photonic lattice into LiNbO3：Fe crystal by using the method of light-induced photonic lattices.Furthermore,we study the minimum value of the density of the written crystal lattice period and the relationship between the crystal lattice period and diffraction efficiency,and compare the cases when lasers at different wavelengths are used to write.Experimental results show that when the writing pe-riod is the minimum,it is one half of the incident wavelength and at this moment two beams of incident light form a standing wave.We find that the diffraction efficiency is higher within the included angle between the two teams of 20°and lower over 25°.We conclude that in order to obtain photonic lattices with high diffraction efficiency,the included angle should be within 20°and short wavelength lasers used as the irradiation light source.

关 键 词：非线性光学 光诱导光子晶格 掺铁铌酸锂晶体 晶格周期 衍射效率 

分 类 号：O437[机械工程—光学工程]