光子Moiré超晶格薄膜的设计及光学特性研究  

Design and Optical Characteristics of Photonic MoiréSuperlattice Films

作　　者：赵富源 孙晓红[1] Zhao Fuyuan;Sun Xiaohong(Henan Key Laboratory of Laser and Opto-Electric Information Technology,School of Electrical and Information Engineering,Zhengzhou University,Zhengzhou 450001,Henan,China)

机构地区：[1]郑州大学电气与信息工程学院河南省激光与光电信息技术重点实验室,河南郑州450001

出　　处：《光学学报》2024年第4期355-362,共8页Acta Optica Sinica

基　　金：国家自然科学基金(12104413)。

摘　　要：二维光子Moiré超晶格拥有一些常规光子晶体不具备的特性,例如平带特征和不同于安德森局域化的光局域现象。本文利用多光束干涉法构建二维光子Moiré超晶格结构,采用有限元法对其能带结构及光场特性进行研究。通过优化Moiré晶格厚度、空气孔半径对其平带及局域特性的影响,得到了高局域特性的Moiré晶格结构。研究中发现,正方晶格具有不同于六角晶格的准狄拉克锥光局域化效应。本文研究结果对发展高性能微纳结构器件具有重要参考价值。Objective The two-dimensional photonic Moirésuperlattice(PMS)possesses some properties that conventional photonic crystals do not have,such as flat-band features and optical localization phenomena different from Anderson localization.We construct the two-dimensional photonic Moirésuperlattice by multiple-beam interference and investigate its band structure and optical field properties via the finite element method.By optimizing the effects of square photonic Moirésuperlattice flims(SPMSs)thickness and air-hole radius on its flat-band and localization properties,the structure of SPMSs with high localization properties is obtained.The square lattice is found to have an optical localization effect of quasi-Dirac cone different from that of the hexagonal lattice.Our study provides reference significance for the development of highperformance micro-and nanostructured devices.Methods We adopt MATLAB software to simulate the multiple-beam interference for preparing SPMSs,and add the threshold processing part in the algorithm to optimize the blurring phenomenon in the interferogram due to the uneven distribution of interfering light intensity.Then,square lattice photonic crystals and SPMSs with clearer structures can be obtained,and the sublattice air-hole radius r of the SPMSs can be controlled by changing the threshold value.The SPMSs model prepared uses perfectly matched layers and periodic boundary conditions.The eigenmodes and band structures are calculated using the finite element method.Comparative simulations are carried out by varying r and film thickness h to test whether these two parameters affect the local and flat band properties of SPMSs.Conclusions Optical localization and flat-band properties exist in SPMSs as in HPMSs,while quasi-Dirac cone localization phenomena exist in SPMSs differently from HPMSs.The sublattice air-hole radius of SPMSs r and the film thickness h affect the localization and flat-band properties of SPMSs.Specifically,smaller values deform localized modes and reduce flat-band proper

关 键 词：光子晶体 光子Moiré超晶格 多光束干涉 平带 光局域 

分 类 号：O436[机械工程—光学工程]