基于Y缺陷的多支路型光子晶体出射光集束  

Multi-Branch Photonic Crystal Exiting Light Bundle Based on Y-Shaped Defect

作　　者：胡帆 文化锋[1] 周华英 武晴涛 王红华 尹希雷 施锋 Hu Fan;Wen Huafeng;Zhou Huaying;Wu Qingtao;Wang Honghua;Yin Xilei;Shi Feng(College of Information Science and Engineering,Ningbo University,Ningbo,Zhejiang 315211 China;不详)

机构地区：[1]宁波大学信息科学与工程学院,浙江宁波315211 [2]Department of Electrical Engineeringand Renewable Energy Engineering,Oregon Institute of Technology,3201 Campus Drive,Klamath Falls,OR 97601,USA

出　　处：《中国激光》2020年第8期198-204,共7页Chinese Journal of Lasers

基　　金：国家自然科学基金(61371061);宁波市自然科学基金(2016A610060)。

摘　　要：衍射效应会导致出射光发散到各个方向。为了减小衍射效应带来的发散效果,并解决出射端波导辐射距离短、辐射效率低的问题,采用二维正方晶格光子晶体构建了一种新型的光子晶体波导出射口结构。首先采用Y型通道结构来提高输出端的透射率;然后采用多支路结构进行耦合,以提高出射光的集束性,从而增大光波的辐射距离;最后进一步优化了出射口的周期数。通过平面波展开法和时域有限差分法进行分析和仿真,仿真结果表明:在辐射距离为110μm处,辐射光波的发散角度约为3°,辐射效率可达到25%以上;具有Y型缺陷、出射口数目为16,并且出射口周期数为4的正方晶格光子晶体能够实现良好的定向辐射。Diffraction can cause beam divergence.In this study,a new type of waveguide exit port structure was constructed for a photonic crystal by adopting a two-dimensional square-lattice photonic crystal to reduce the divergence and deal with the short radiation distance and low radiation efficiency of the waveguide exit port.First,a Y-shaped channel structure was used for improving the transmittance at the output end;then,multi-branch structures was coupled for improving the convergence of the emitted light to increase the radiation distance of the light wave.Finally,the exit port period was optimized.In addition,analyses and simulations were conducted using the plane wave expansion method and the finite-difference time-domain method.The simulation result denoted that the divergence angle of the emitted light was approximately 3°and that the radiation efficiency exceeded 25%when the radiation distance of the light was 110μm.Thus,a square-lattice photonic crystal with a Y-shaped defect,16 exit ports,and 4 exit port periods can achieve well-directed radiation.

关 键 词：集成光学 光子晶体 缺陷 辐射 多支路 出射场 

分 类 号：TN256[电子电信—物理电子学]