基于多平面光转换的厄米-高斯光束产生和模式分离  

Generation and Mode Separation of Hermite‒Gauss Beams Based on Multi-Plane Light Conversion

作　　者：马天宝 祁玲珍 彭姝 李佳明 郭旭联 刘奎[1,2] Ma Tianbao;Qi Lingzhen;Peng Shu;Li Jiaming;Guo Xulian;Liu Kui(State Key Laboratory of Quantum Optics and Quantum Optics Devices,Institute of Opto-Electronics,Shanxi University,Taiyuan 030006,Shanxi,China;Collaborative Innovation Center of Extreme Optics,Shanxi University,Taiyuan 030006,Shanxi,China)

机构地区：[1]山西大学光电研究所量子光学与光量子器件国家重点实验室,山西太原030006 [2]山西大学极端光学协同创新中心,山西太原030006

出　　处：《光学学报》2024年第16期329-337,共9页Acta Optica Sinica

基　　金：国家重点研发计划(2021YFC2201802);中央引导地方科技发展资金(YDZJSX20231A001)。

摘　　要：高质量的高阶厄米-高斯光束的产生和模式分离技术对大容量光通信和空间测量具有重要意义。搭建了基于多平面光转换(MPLC)的模分复用器进行模式整形,并获得高质量的厄米-高斯(HG)光束,其中HG1,0、HG2,0、HG3,0、HG4,0和HG5,0的模式纯净度分别为93.9%、96.8%、76.6%、88.1%和85.3%。使用高斯光束偏移入射MPLC可实现六通道模式分离,最大串扰为-11.9 dB。所提的厄米-高斯光束模式整形和分离技术有望应用到空间小位移测量和超分辨成像中。Objective The high-order transverse mode optical field with a special spatial structure utilizes the spatial dimension resources of photons,providing a novel method to address the capacity crisis in optical communication and facilitate the sustainable development and expansion of high-speed,high-capacity optical communication.As a fundamental high-order transverse mode optical field,the Hermite‒Gauss beam is widely used in space quantum measurement in addition to optical communication.Moreover,the Hermite‒Gauss beam is also employed in achieving super-resolution imaging.However,due to the lack of an effective Hermite‒Gauss mode separation device,it is challenging to surpass the Cramér-Rao measurement lower bound in experiments.Therefore,the generation and mode separation of high-quality higher-order Hermite‒Gauss modes play a crucial role in spatial quantum measurement.Hermite‒Gauss beams can be generated using phase-plates,specially designed lasers,spatial light modulators,and mode cleaners.However,most of these methods suffer from low conversion efficiency.In 2014,CAILabs in France pioneered multi-plane light conversion(MPLC)technology.The mode division multiplexer based on MPLC solves the problem of low conversion efficiency,enabling the preparation of high-purity high-order mode beams and achieving spatial mode division multiplexing.Subsequently,MPLC has significantly influenced optical communication,quantum cryptography,and quantum computing.Currently,domestic research on MPLC mainly focuses on the modular division multiplexing of linear polarization(LP)mode and orbital angular momentum(OAM)mode,while the preparation and mode decomposition of Hermite‒Gauss mode based on MPLC are rarely reported.Methods The laser output infrared light with a wavelength of 1080 nm is coupled into a single-mode fiber after passing through a line polarizer,and the beam is ejected from the optical fiber coupler to be incident into MPLC as a plane wave.Five reflections between the liquid crystal surface and the cavity

关 键 词：量子光学 空间光调制器 厄米-高斯光束 模分复用 光束整形 

分 类 号：O436[机械工程—光学工程]