一维TiO_(2)亚波长光栅的衍射异常现象及其结构设计  

Diffraction Anomalies and Structural Design of One-dimensional TiO_(2) Subwavelength Gratings

作　　者：臧茂荣 贾志刚 董海亮[1] 张爱琴 梁建[3] 马淑芳 许并社[1,4] Zang Maorong;Jia Zhigang;Dong Hailiang;Zhang Aiqin;Liang Jian;Ma Shufang;Xu Bingshe(Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of Education,Taiyuan University of Technology,Taiyuan 030024,Shanxi,China;College of Textile Engineering,Taiyuan University of Technology,Taiyuan 030024,Shanxi,China;College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,Shanxi,China;Institute of Atomic and Molecular Science,Shaanxi University of Science&Technology,Xi'an 710021,Shaanxi,China)

机构地区：[1]太原理工大学新材料界面科学与工程教育部重点实验室,山西太原030024 [2]太原理工大学轻纺工程学院,山西太原030024 [3]太原理工大学材料科学与工程学院,山西太原030024 [4]陕西科技大学材料原子·分子科学研究所,陕西西安710021

出　　处：《光学学报》2022年第9期56-63,共8页Acta Optica Sinica

基　　金：国家自然科学基金(21972103,61904120,61604104,51672185);国家重点研发计划(2016YFB0401803);山西省基础研究项目(201801D221183,201801D221124,201801D121101,201901D111111,201901D111127,201901D211090);山西省重点研发项目(201803D31042);山西浙大新材料与化工研究院研发项目(2021SX-AT001)。

摘　　要：研究了一维TiO_(2)亚波长光栅(SWG)的衍射异常现象,具体表现为泄漏模共振效应和瑞利异常。研究表明,一定参数条件下的横磁波(TM偏振)和横电波(TE偏振)入射均会出现瑞利异常和泄漏模共振效应。在TM偏振光情况下,会出现传统的窄带、高衍射效率泄漏模共振效应,而在TE偏振光情况下,由于多个接近的泄漏模共振峰相互叠加,故会形成宽带、高衍射效率的反射谱。采用严格耦合波理论计算了一维TiO_(2)SWG的衍射效率,研究了光栅周期、高度和占空比对光栅反射率的影响。当光栅周期为0.49μm,高度为0.25μm,占空比为0.34时,SWG具有TE偏振选择性,在0.52μm波段处的反射率接近1,且高反带(反射率达到99.9%以上)宽度为26 nm。优化各结构参数,得到光栅周期、占空比、高度的制作容差分别为1.6%、8.3%、2.0%,故SWG理论上可以作为垂直腔面发射激光器的反射镜。The diffraction anomalies of a one-dimensional TiO_(2)subwavelength grating(SWG)are studied,which are characterized by leakage mode resonance effect and Rayleigh anomalies.The results show that Rayleigh anomalies and leakage mode resonance effect occurrs for transverse magnetic wave(TM polarization)and transverse eletric wave(TE polarization)incident under certain parameter conditions.In the case of TM polarized light,the traditional leakage mode resonance effect with narrow band and high diffraction efficiency will occur,while in the case of TE polarized light,due to the superposition of several close leakage mode resonance peaks,the reflection spectra with broad band and high diffraction efficiency will be formed.The diffraction efficiency of a one-dimensiona TiO_(2)SWG is calculated by the rigorous coupled-wave theory(RCWA),and the effects of grating period,height and duty cycle on the reflectivity of the grating are studied.When period,height,and duty cycle of the grating are 0.49μm,0.25μm and 0.34 respectively,the SWG exhibites TE polarization selectivity.The reflectivity at 0.52μm is close to 1,and the high reflection band(reflectivity is higher than 99.9%)had a width of 26 nm.By optimizing the structural parameters,the manufacturing tolerances of the grating period,duty cycle,and height are 1.6%,8.3%,and 2.0%respectively,so the SWG can be theoretically used as the reflector of a vertical cavity surface emitting laser.

关 键 词：衍射 垂直腔面发射激光器 亚波长光栅 TiO_(2) 严格耦合波理论 

分 类 号：O436[机械工程—光学工程]