Femtosecond laser writing of low-loss three-dimensional waveguide coupler in LiNbO_(3) crystal  

作　　者：吕金蔓 李戈 马钰洁 陈峰 Jinman Lü;Ge Li;Yujie Ma;Feng Chen(Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material Technology,Center for Advanced Material Diagnostic Technology,and College of Engineering Physics,Shenzhen Technology University,Shenzhen 518118,China;School of Physics,State Key Laboratory of Crystal Materials,Shandong University,Jinan 250100,China)

机构地区：[1]Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material Technology,Center for Advanced Material Diagnostic Technology,and College of Engineering Physics,Shenzhen Technology University,Shenzhen 518118,China [2]School of Physics,State Key Laboratory of Crystal Materials,Shandong University,Jinan 250100,China

出　　处：《Chinese Optics Letters》2023年第11期118-122,共5页中国光学快报（英文版）

基　　金：supported by the National Natural Science Foundation of China(NSFC)(Nos.20211062020035 and 12005147);Postdoctoral Research Grants(No.20211063010003)。

摘　　要：With different interactions between material and femtosecond lasers,two-dimensional(2D)and three-dimensional(3D)waveguide couplers,whose separation distances are fabricated in z-cut lithium niobate crystal by femtosecond laser writing,are reported.Experimentally and numerically,it is shown from results that the guidance is only propagating along TM polarization due to the Type I modification and holds equal splitting ratios,which are the same as power splitters at632.8 nm.The propagation losses of 2D and 3D waveguide couplers exhibit better transmission properties than those of the previously reported Type I Y-junction waveguide splitters.

关 键 词：femtosecond laser writing beam splitters lithium niobate 

分 类 号：TN25[电子电信—物理电子学] TN249