基于45°辐射倾斜光纤光栅的全光纤偏振相关器件  

All-Fiber Polarization-Dependent Device Based on 45° Radiated Tilted Fiber Grating

作　　者：宋青果 黄成俊 闫志君 孙琪真[1] 刘德明[1] 张琳 无 Song Qingguo;Huang Chengjun;Yan Zhijun;Sun Qizhen;Liu Deming;Zhang Lin;无(School of Optical and Electronic Information,Huazhong University of Science and Technology,Wuhan,Hubei 430030,China;Wuhan National Laboratory for Optoelectronics,Huazhong University of Science and Technology,Wuhan,Hubei 430030,China;Institute of Photonic Technologies,Aston University,Birm ingham B47ET,UK)

机构地区：[1]华中科技大学光学与电子信息学院,湖北武汉430030 [2]华中科技大学武汉光电国家研究中心,湖北武汉430030 [3]阿斯顿大学光子研究中心,英国伯明翰B47ET

出　　处：《光学学报》2020年第23期31-38,共8页Acta Optica Sinica

基　　金：国家重点研究发展计划(2018YFB2100902);湖北省技术创新专项重大项目(2019AAA053,2019AAA059);湖北省自然基金创新群体(2018AAA040);中央高校基本研究基金(2019kfyRCPY095)。

摘　　要：报道一种基于45°辐射倾斜光纤光栅(RTFG)的全光纤偏振相关器件。由于独特的偏振相关模式耦合特性,其可作为一种理想的全光纤起偏器、偏振相关耦合器、全光纤衍射器。基于体电流法建立倾斜光纤光栅的偏振耦合理论,从理论和实验角度系统地分析45°RTFG的偏振辐射耦合、衍射分光及偏振特性。仿真结果和实验结果表明,45°RTFG的透射和辐射有良好的偏振功能。一根长度为24 mm的45°RTFG在波长为1550 nm处的偏振消光比(PER)为22 dB,3 dB带宽超过300 nm。通过制备不同长度的45°RTFG,可以实现具有不同PER的光栅。光栅的辐射模沿角向呈准高斯分布,沿轴向呈指数衰减分布,并且其空间衍射角色散约为0.054 (°)/nm。实验结果与理论结果完全匹配,45°RTFG具有潜在的应用前景。In this study, an all-fiber polarization-dependent device based on a 45° radiated tilted fiber grating(RTFG) is reported. Owing to its unique polarization-dependent mode coupling characteristics, this device can be used as an ideal all-fiber polarizer, polarization-dependent coupler, and all-fiber diffraction device. Based on the volume current method, the polarization coupling theory for tilted fiber gratings is established. The polarization radiation coupling, diffraction splitting, and polarization characteristics of the 45° RTFG are systematically analyzed theoretically and experimentally. Simulation and experimental results show that the transmission and radiation of the 45° RTFG exhibit good polarization function. The 45° RTFG with a length of 24 mm shows a polarization extinction ratio(PER) of 22 dB at a wavelength of 1550 nm, and the 3-dB bandwidth is more than 300 nm. Moreover, the grating with different PER can be prepared by changing the grating length. The radiation mode distribution of the 45° RTFG is measured, which indicates a quasi-Gaussian profile and exponential reduction along the azimuthal and axial directions, respectively. The spatial diffraction angular dispersion is approximately 0.054(°)/nm, which is consistent with the simulation result. The 45° RTFG has potential application prospects.

关 键 词：光纤光学 光纤器件 倾斜光纤光栅 光纤衍射器件 光纤偏振器件 

分 类 号：TN253[电子电信—物理电子学]