基于二氧化硅覆盖的铌酸锂波导产生有效二次谐波的研究  

Study on second harmonic generated by lithium niobate waveguide covered with silicon dioxide

作　　者：张龚业 蒋建[1] 杨继杰 ZHANG Gongye;JIANG Jian;YANG Jijie(School of Electronic and Optical Engineering,Nanjing University of Posts and Telecommunications,School of Flexible Electronics(Future Technology),Nanjing 210023 China)

机构地区：[1]南京邮电大学电子与光学工程学院、柔性电子(未来技术)学院,南京210023

出　　处：《光通信技术》2023年第4期15-20,共6页Optical Communication Technology

基　　金：国家自然科学基金项目(62175116、62075099)资助。

摘　　要：为了在波导中轻松实现相互作用波之间的相位匹配,产生有效的二次谐波,设计了一种新型条形波导——二氧化硅-铌酸锂-二氧化硅(SiO_(2)-LiNbO_(3)-SiO_(2)),该条形波导由SiO_(2)和无蚀刻z切割的LiNbO_(3)组成,通过调整波导结构分析了波导的色散,研究了不同尺寸的SiO_(2)对基波与二次谐波相位匹配点的影响,分析了该条形波导倍频的可行性,并利用脉冲的振幅和宽度对频谱展宽的特性,实现超宽带连续谱。仿真结果表明:在覆盖层SiO_(2)宽度为1600 nm、高度为400 nm的条形波导结构中,使用脉冲振幅为107 a.u.,脉冲宽度为10 fs的超短脉冲,得到了一个带宽为1302.5 nm的超宽带连续谱。In order to easily achieve phase matching between interacting waves in waveguide and generate effective second harmonics,a new type of strip waveguide silica-lithium niobate-silicon dioxide(SiO_(2)-LiNbO_(3)-SiO_(2))is designed.The strip wave-guide is composed of SiO_(2)and LiNbO_(3)without etching z cutting.The dispersion of the waveguide is analyzed by adjusting the waveguide structure,and the influence of SiO_(2)with different sizes on the phase matching points of the fundamental wave and the second harmonic is studied.The feasibility of frequency doubling of the strip waveguide is analyzed,and the ultra-wideband continuous spectrum is realized by using the characteristics of the amplitude and width of the pulse to broaden the spectrum.The simulation results show that an ultra-short pulse with a pulse amplitude of 107 a.u.and a pulse width of 10 fs is used to obtain an ultra-wideband continuous spectrum with a bandwidth of 1302.5 nm in a strip waveguide structure with a covering layer SiO_(2)width of 1600 nm and a height of 400 nm.

关 键 词：铌酸锂 相位匹配 二次谐波产生 超连续谱 光通信 

分 类 号：TN929.1[电子电信—通信与信息系统]