基于Al_(0.9)Ga_(0.1)As/Al_(2)O_(3)亚波长光栅的偏振分束器设计  

Design of Polarization Beam Splitter Based on Al_(0.9)Ga_(0.1)As/Al_(2)O_(3) Subwavelength Grating

作　　者：于传洋 范鑫烨 房文敬 赵和宁 毕丽平 刘澜涛 Yu Chuanyang;Fan Xinye;Fang Wenjing;Zhao Hening;Bi Liping;Liu Lantao(Shandong Key Laboratory of Optical Communication Science and Technology,School of Physics Science and Information Engineering,Liaocheng University,Liaocheng 252000,Shandong,China)

机构地区：[1]聊城大学物理科学与信息工程学院山东省光通信科学与技术重点实验室,山东聊城252000

出　　处：《激光与光电子学进展》2022年第13期139-144,共6页Laser & Optoelectronics Progress

基　　金：山东省重点研发计划(软科学项目)重点项目(K20LB1401);信息光子学与光通信国家重点实验室(北京邮电大学)开放基金(IPOC2019A009)。

摘　　要：基于Al_(0.9)Ga_(0.1)As/Al_(2)O_(3)亚波长光栅设计了一种高性能偏振分束器。该偏振分束器由Al_(0.9)Ga_(0.1)As和Al_(2)O_(3)交替形成,制备简单、结构稳定且易于集成。采用严格耦合波分析方法对光栅反射率和占空比、周期的变化关系进行了分析,通过选取合适的光栅参数实现光栅结构对横电(TE)、横磁(TM)偏振光不同的衍射特性,进而实现了偏振分束功能。仿真和计算结果表明,在80 nm(800~880 nm)宽光谱范围内,该光栅偏振分束器对TE偏振光的反射率大于94%,对TM偏振光的透射率大于90%,且偏振消光比大于10 dB,最高可达41.37 dB。此外,还研究了光栅参数变化和入射角度偏转对偏振分束器性能的影响。结果表明,该偏振分束器具有良好的工艺容差,对垂直入射有左右各偏转4°的容忍性,有效解决了传统偏振分束器难以集成和制备工艺复杂的问题,可与GaAs基器件集成后实现对入射光束的调控。A high-performance polarizing beam splitter is designed based on Al_(0.9)Ga_(0.1)As/Al_(2)O_(3) subwavelength grating in this paper.The polarizing beam splitter is alternately formed by using Al_(0.9)Ga_(0.1)As and Al_(2)O_(3),the preparation is simple,and the structure is stable and easy to integrate.The relationship between the reflectivity,duty cycle and period of the grating is analyzed by the rigorous coupled wave analysis method.By selecting the appropriate grating parameters,the grating structure can achieve different diffraction characteristics of transverse electric(TE)and transverse magnetic(TM)polarized light,and the polarization beam splitting function is realized.The simulation and calculation results show that in the wide spectral range of 80 nm(800-880 nm),the reflectivity of the grating polarization beam splitter for TE polarized light is greater than 94%,the transmittance of TM polarized light is greater than 90%,and the polarization extinction ratio is greater than 10 dB,up to 41.37 dB.In addition,the effects of grating parameter variation and incident angle deflection on the performance of the polarizing beam splitter are also investigated.The results show that the polarizing beam splitter has good process tolerance and can tolerate 4°of left and right deflections for vertical incidence,which effectively solves the problems of difficult integration and complex fabrication of traditional polarizing beam splitters,and can be combined with GaAs-based devices.After integration,the control of the incident beam is realized.

关 键 词：亚波长光栅 偏振分束器 严格耦合波分析 偏振消光比 

分 类 号：TN256[电子电信—物理电子学]