基于超构表面多通大容量完美矢量涡旋光束的产生及调控研究  

Generation and independent-manipulation of multi-channel high-capacity perfect vector vortex beams based on geometric metasurfaces

作　　者：张胜蓝 田喜敏 许军伟 徐亚宁 李亮[1] 刘杰龙 ZHANG Shenglan;TIAN Ximin;XU Junwei;XU Yaning;LI Liang;LIU Jielong(School of Materials Science and Engineering,Zhengzhou University of Aeronautics,Zhengzhou 450046,China)

机构地区：[1]郑州航空工业管理学院材料学院,郑州450046

出　　处：《物理学报》2025年第6期50-60,共11页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:12004347);河南省科技公关(批准号:242102211081,232102320057);河南省青年骨干工程(批准号:2023GGJS113);河南省高等学校重点科研项目(批准号:24A140025,25B140009);航空科学基金(批准号:2020Z073055002)资助的课题.

摘　　要：完美矢量涡旋光束除具有螺旋相位、环状强度分布及非均匀偏振分布外,其亮环半径及环宽度恒定,不受拓扑荷数变化的影响,且同时携带自旋角动量和轨道角动量,因此在很多光学领域具有重要应用.超构表面作为一种亚波长结构排列而成的平面光学器件,能够精准调控电磁波的相位、偏振和振幅,为集成化矢量光场调控器件的实现提供变革性解决方案.然而,现有超构表面在生成产生多通大容量、偏振和轨道角动量独立操控的完美矢量涡旋光束方面仍面临严峻挑战.为此,本文基于超构表面平台,利用纯几何相位调制的自旋多路复用方案,通过叠加两正交偏振完美涡旋光束,实现了多通大容量完美矢量涡旋光束.通过调控两正交偏振完美涡旋光束的初始相位差、振幅比及拓扑荷数,实现了具备任意偏振阶次和偏振分布特性的完美矢量涡旋光束;通过精心设计超构表面相位分布及光束传播路径,生成了多重完美矢量涡旋光束阵列.此外,基于完美矢量涡旋光束偏振阶次和偏振态两个并行维度,本文成功演示了一种兼具安全性高和强鲁棒性的光学信息加密方案.该工作旨在建立一个超紧凑、稳健的平台,以在中红外波段生成多通大容量完美矢量涡旋光束,推动其在光学加密、粒子操控和量子光学等领域的应用.Perfect vector vortex beams(PVVBs),which are characterized by spiral phase,donut-shaped intensity profile and inhomogeneous polarization of a light beam carrying spin angular momentum(SAM)and orbital angular momentum(OAM),have a constant bright ring radius and ring width which are unaffected by the changes of their carrying topological charge(TC),thus making them highly valuable in many optical fields.Metasurfaces,as planar optical devices composed of subwavelength nanostructures,can precisely control the phase,polarization,and amplitude of electromagnetic waves,providing a revolutionary solution for integrated vector field manipulation devices.However,existing metasurfaces still encounter significant challenges in generating high-capacity,polarization-and orbital angular momentum-independent controlled perfect vector vortex beams.In order to solve this problem,in this work a spin-multiplexing scheme based on pure geometric phase modulation on a metasurface platform is used to achieve high-capacity polarization-and OAMindependent controlled PVVBs.The metasurfaces with a combined phase profile of a spiral phase plate,an axicon,and a focusing(Fourier)lens are spatially encoded by rectangular Ge2Sb2Se4Te1(GSST)nanopillar with various orientations on a CaF_(2) square substrate.When illuminated by circularly polarized light with opposite chirality,the metasurfaces can generate various perfect vector vortex beams(PVBs)with arbitrary topological charges.For linearly polarized incidence,the metasurface is employed to induce PVVBs by coherently superposing PVBs with spin-opposite OAM modes.The polarization states and polarization orders of the generated PVVBs can be flexibly customized by controlling the initial phase difference,amplitude ratio,and topological charges of the two orthogonal PVB components.Notably,through precisely designing the metasurface’s phase distribution and the propagation path of the generated beams,the space and polarization multiplexing can be realized in a compact manner of spatial PVVB arrays

关 键 词：超构表面 完美矢量涡旋光束 完美涡旋光束 自旋角动量 轨道角动量 

分 类 号：O43[机械工程—光学工程]