Learning to recognize misaligned hyperfine orbital angular momentum modes  

作　　者：Xiao Wang Yufeng Qian JingJing Zhang Guangdong Ma Shupeng Zhao RuiFeng Liu Hongrong Li Pei Zhang Hong Gao Feng Huang Fuli Li 

机构地区：[1]Shaanxi Province Key Laboratory of Quantum Information and Quantum Optoelectronic Devices,School of Physics,Xi’an Jiaotong University,Xi’an 710049,China [2]School of Mechanical Engineering and Automation,Fuzhou University,Fuzhou 350108,China

出　　处：《Photonics Research》2021年第4期I0001-I0006,共6页光子学研究（英文版）

基　　金：National Natural Science Foundation of China(11534008,91736104);Ministry of Science and Technology of the People's Republic of China(2016YFA0301404);Fundamental Research Funds for the Central Universities.

摘　　要：Orbital angular momentum(OAM)-carrying beams have received extensive attention due to their high-dimensional characteristics in the context of free-space optical communication.However,accurate OAM mode recognition still suffers from reference misalignment of lateral displacement,beam waist size,and initial phase.Here we propose a deep-learning method to exquisitely recognize OAM modes under misalignment by using an alignment-free fractal multipoint interferometer.Our experiments achieve 98.35% recognizing accuracy when strong misalignment is added to hyperfine OAM modes whose Bures distance is 0.01.The maximum lateral displacement we added with respect to the perfectly on-axis beam is about±0.5 beam waist size.This work offers a superstable proposal for OAM mode recognition in the application of free-space optical communication and allows an increase of the communication capacity.

关 键 词：INTERFEROMETER MOMENTUM BEAM 

分 类 号：TN929.1[电子电信—通信与信息系统]