基于Si/SiN_(x)双层波导的偏振无关光功分器  

Design of Polarization-independent Optical Power Splitter based on Si/SiN_(x)Double-layer Waveguide

作　　者：刘海广 张跃腾 宋雨辰 沈晗潇 陈鹤鸣 汪静丽[1] LIU Hai-guang;ZHANG Yue-teng;SONG Yu-chen;SHEN Han-xiao;CHEN He-ming;WANG Jing-li(College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology),Nanjing University of Posts and Telecommunications,Nanjing 210023,China;Bell Honors School,Nanjing University of Posts and Telecommunications,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 [2]南京邮电大学贝尔英才学院,南京210023

出　　处：《光通信研究》2022年第4期42-46,共5页Study on Optical Communications

基　　金：国家自然科学基金资助项目(61571237);江苏省自然科学基金资助项目(BK20151509);南京邮电大学校级科研基金资助项目(NY217047)。

摘　　要：针对目前大部分偏振无关光功分器结构复杂和损耗大的问题,文章设计了一种基于Si/SiN_(x)双层波导的偏振无关光功分器,用于1550 nm波长光信号的1×2均匀功分。通过等离子体增强化学气相沉积(PECVD)方法调节Si/SiN_(x)层的折射率,使同一波长下横电(TE)和横磁(TM)偏振模的二重像点位置相等,实现偏振无关功能。同时,通过对多模干涉波导宽度的合理选择,减小器件尺寸。通过优化锥形波导,进一步降低器件的插入损耗和反射损耗。运用三维(3D)有限时域差分方法进行建模仿真,仿真结果表明,文章所提偏振无关光功分器尺寸仅为3.0μm×16.8μm,插入损耗和反射损耗分别低至0.04和-48.80 dB,分光比达到了1.00033,插入损耗小于1 dB,带宽可达380 nm,在未来的集成光路中具有潜在的应用价值。Aiming at the problems that most polarization-independent optical power splitters have complex structure and high loss,a polarization-independent 1×2 power splitter based on Si/SiN_(x)double-layer waveguide is designed in this paper,which is used for equally splitting 1550 nm optical signals.The refractive index of SiNmaterial can be adjusted by the Plasma Enhanced Chemical Vapor Deposition(PECVD).The beat lengths of Transverse Electric(TE)polarization mode and Transverse Magnetic(TM)polarization mode is equal,and the polarization independent function is realized.Meanwhile,the device size is reduced by selecting the width of the multimode interference waveguide.And the insertion loss and reflection loss are further reduced by optimizing the taper waveguide.The 3 D finite-difference time-domain method is used for modeling and simulation.The results show that the size of the proposed optical power splitter is only 3.0μm×16.8μm,and the insertion loss,reflection loss and splitting ratio are as low as 0.04 and-48.80 dB,and 1.00033,respectively.The bandwidth can reach 380 nm with insertion loss less than 1 dB,which has potential application value in the future integrated optical path.

关 键 词：光功分器 多模干涉 SiN_(x) 偏振无关 

分 类 号：TN256[电子电信—物理电子学]