微米量级薄膜铌酸锂脊型波导中高效非线性频率转换(特邀)  

Efficient Nonlinear Frequency Conversion in Microscale Thin-Film Lithium Niobate Ridge Waveguides(Invited)

作　　者：丁文君 张玉婷 仇晶 唐永志 张景 丁婷婷 黎浩 刘时杰 郑远林 陈险峰 Ding Wenjun;Zhang Yuting;Qiu Jing;Tang Yongzhi;Zhang Jing;Ding Tingting;Li Hao;Liu Shijie;Zheng Yuanlin;Chen Xianfeng(State Key Laboratory of Advanced Optical Communication Systems and Networks,School of Physics and Astronomy,Shanghai Jiao Tong University,Shanghai 200240,China;Institute of Semiconductors,Chinese Academy of Sciences,Beijing 100083,China;School of Electronic and Electrical Engineering,Shanghai University of Engineering Science,Shanghai 201620,China;Shanghai Research Center for Quantum Sciences,Shanghai 201315,China;Shandong Provincial Engineering and Technical Center of Light Manipulations,Shandong Normal University,Jinan 250358,Shandong,China)

机构地区：[1]区域光纤通信网与新型光通信系统国家重点实验,上海交通大学物理与天文学院,上海200240 [2]中国科学院半导体研究所,北京100083 [3]上海工程技术大学电子电气工程学院,上海201620 [4]上海量子科学研究中心,上海201315 [5]山东师范大学光场调控及应用中心,山东济南250358

出　　处：《光学学报》2024年第15期92-100,共9页Acta Optica Sinica

基　　金：科技部重点研发计划(2022YFA1205101,2023YFA1407202);国家自然科学基金(12192252,12074252,62105323);上海市市级重大专项(2019SHZDZX01-ZX06);阳阳发展基金。

摘　　要：铌酸锂基集成光子学在过去几十年里一直备受关注,近年来薄膜铌酸锂的出现更是极大地推动了该领域的发展。本文利用紫外光刻和干法刻蚀技术在3μm厚的薄膜铌酸锂上制备了微米波导(横截面为2.6μm×3μm),光纤波导耦合损耗仅1.2 dB/facet。周期极化薄膜铌酸锂微米波导在通信波段下实现了高效的二次谐波(倍频)产生,归一化转换效率达到164%W^(-1)·cm^(-2),并在1 W基频光输入条件下展现出57%的高效的绝对频率转换。同时,该微米波导还可实现高效的和频转换,在300 mW泵浦光下的小信号和频上转换效率为139%。优秀的频率转换性能、可规模化制备以及良好的光纤兼容性使微米量级薄膜铌酸锂展现出巨大的吸引力,未来有望发展更多的多功能器件并推动集成光子学的基础研究和光量子信息的应用发展。Objective Lithium niobate based integrated photonics has been receiving extensive attention over the past decades,and its development has gained significant momentum recently thanks to the emergence of lithium niobate on insulator(LNOI).While ensuring the high performance of the device,scalable fabrication and fiber compatibility are also particularly important for practical applications.Micrometer waveguides based on 3-μm thick LNOI show excellent integration potential.For example,the lens fiber or high numerical aperture fiber can be directly coupled with the micro-waveguide with high efficiency,and the overall insertion loss of the device is small.The fabrication process of micro-waveguides by UV lithography and plasma dry etching features low fabrication cost and technical difficulty.In addition,the mode area of micro-waveguides is several times smaller than that of conventional proton-exchange or titanium indiffused waveguides,which ensures higher conversion efficiency.Here we propose to design and fabricate the LNOI micro-waveguide on 3-μm thick LNOI,demonstrating its high performance in second harmonic generation(SHG)and sum-frequency generation(SFG)at the optical telecommunication band.The excellent frequency conversion capability,scalable fabrication,and fiber compatibility make the LNOI micro-waveguide highly appealing.We expect it to form a variety of functional devices in the future and promote the development of fundamental physics research and optical quantum information applications based on integrated photonics.Methods We fabricate the periodically poled LNOI(PPLNOI)micro-waveguide by direct electric poling followed by UV lithography and plasma dry etching techniques.We adopt the first-order quasi-phase matching(QPM)at 1550 nm,which determines the poling period.A 3-μm z-cut magnesium-doped lithium niobate on insulator(MgO∶LNOI)wafer is patterned via ultraviolet lithography and electron beam evaporation for electrodes.The electrodes are used for direct electric poling to achieve periodic domai

关 键 词：非线性光学 薄膜铌酸锂 周期极化铌酸锂 准相位匹配 高效频率转换 

分 类 号：O436[机械工程—光学工程]