三维准相位匹配研究进展  

Advances in Three-Dimensional Quasi-Phase Matching

作　　者：杜金恒 宋伟[2] 张怀金[1] Du Jinheng;Song Wei;Zhang Huaijin(State Key Laboratory of Crystal Materials,Institute of Crystal Materials,Shandong University,Jinan,Shandong 250100,China;CETC Deqing Huaying Electronics Co.,Ltd.,Huzhou,Zhejiang 313000,China)

机构地区：[1]山东大学晶体材料研究所晶体材料国家重点实验室,山东济南250100 [2]中电科技德清华莹电子有限公司,浙江湖州313000

出　　处：《中国激光》2021年第12期236-262,共27页Chinese Journal of Lasers

基　　金：国家自然科学基金重点项目(51632004);国家自然科学基金面上项目(51772172)。

摘　　要：非线性光子晶体(nonlinear photonic crystal,NPC)具有空间相关的二阶非线性系数,可以通过准相位匹配(quasi-phase matching,QPM)有效地控制非线性光学相互作用。一维和二维NPC已被广泛用于激光频率转换、空间光调制和非线性光学成像中。然而,受传统极化方法的限制,三维(3D)NPC的实现仍然是非线性光学领域的最大挑战之一。从准相位匹配的基本理论出发,综述了目前利用飞秒激光选择性地擦除铌酸锂(LiNbO_(3),LN)晶体非线性系数的3D LN NPC实验进展、在铁电钛酸钡钙(Ba_(0.77)Ca_(0.23)TiO_(3),BCT)晶体的自发畴结构中实现3D调制的QPM以及使用激光直写技术在BCT晶体中制造3D NPC的进展。另外,还介绍了一种具有自发的魔方立方状畴结构的天然钽铌酸钾(KTa_(0.56)Nb_(0.44)O_(3),KTN)钙钛矿NPC,无需外部极化即可直接满足3D QPM条件。3D NPC晶体可以广泛应用于需要产生和控制新频率光的领域,实现非线性光束整形、非线性成像和三维非线性全息等应用。Significance The quasi-phase matching theory proposed by Bloembergen provides an effective method for phase mismatch compensation and conversion efficiency improvement in the process of nonlinear optical interaction.In order to fulfil the quasi-phase matching conditions,nonlinear photonic crystals,domain modulated LiNbO3,LiTaO3and other ferroelectric materials,have been extensively studied in the past few decades.The quasi-phase matching technology has gained in-depth research and made a great progress at the one-dimensional and twodimensional levels,and it is used for efficient frequency conversion in nonlinear optics.Due to the existence of collinear and non-collinear reciprocal vectors,many interesting phenomena have been discovered,including nonlinear optical frequency conversion,nonlinearˇCerenkov radiation,conical second-harmonic generation,and nonlinear Talbot self-imaging.Three-dimensional nonlinear photonic crystals can realize a variety of new nonlinear optical interaction processes,such as synchronous quasi-phase matching of different nonlinear processes,volume nonlinear holography,nonlinear beam shaping,etc.However,because the traditional periodic structure preparation techniques such as the electric field polarization method are difficult to achieve three-dimensional control of nonlinear coefficients,the preparation of three-dimensional nonlinear photonic crystals has not made a major breakthrough,which is the bottleneck of the experimental research of the current three-dimensional quasi-phase matching process.Progress Lithium niobate crystal,one of the most popular nonlinear photonic crystal materials(Table 1),can be experimentally verified and easily obtained by researchers working in the field of nonlinear optics,and the experiment is compatible with the current nonlinear optical modulation technology.The requirements of laser direct writing are relatively easy to meet,especially along the depth direction(Figs.5and 6)and can be easily extended to various nonlinear crystals including LiTaO3and KTP

关 键 词：非线性光学 三维准相位匹配 铌酸锂晶体 钛酸钡钙晶体 钽铌酸钾晶体 

分 类 号：O437.4[机械工程—光学工程]