摘要
超构表面在纵向方向上的调控为控制偏振状态引入了新的维度,为了实现偏振态随传播方向的演化,文章提出了一种基于几何相位调制的超构表面,可以同步实现纵向聚焦、涡旋及偏振态的演化。该设计基于复振幅的叠加方法来构建结构,并通过时域有限差分方法(FDTD)进行了数值仿真验证。仿真的结果表明,所设计的超构表面在纵向上从焦点演化到涡旋的过程中,可以同时实现正交线偏振态的演化;进一步设计了双涡旋的纵向偏振演化,同时也实现了涡旋拓扑荷的演化。这种沿传播方向动态调控偏振态的方法,为开发光控可切换器件及推动光–物质相互作用的研究开辟了新的应用前景。
Metasurfaces with longitudinal modulation capabilities introduce a new dimension for polarization state control.To achieve polarization evolution along the propagation direction,this article proposes a geometric-phase-modulated metasurface that simultaneously enables longitudinal focusing,vor-tex generation,and polarization evolution.The design employs a complex-amplitude superposition method for structural configuration,validated through finite-difference time-domain(FDTD)nu-merical simulations.Results demonstrate that the metasurface facilitates orthogonal linear polariza-tion evolution during the longitudinal transition from focused spots to vortex beams.Furthermore,we implement dual-vortex configurations exhibiting longitudinal polarization evolution while enabling dynamic modulation of vortex topological charges.This approach to dynamically manipulate polariza-tion states along the propagation axis opens new prospects for developing optically controlled switch-able devices and advancing light-matter interactions.
作者
张腾
Teng Zhang(School of Optical-Electrical and Computer Engineering,University of Shanghai for Science and Technology,Shanghai)
出处
《建模与仿真》
2025年第5期203-210,共8页
Modeling and Simulation
关键词
超构表面
几何相位
聚焦
涡旋
偏振演化
Metasurface
Geometric Phase
Focusing
Vortex
Polarization Evolution
