【作者】 黄婷；

【导师】 王任；

【作者基本信息】 电子科技大学 ， 物理学， 2025， 硕士

【摘要】 相较于传统涡旋光所具有的纵向轨道角动量(其方向与光传播方向平行),空时涡旋场作为新型空时结构电磁场,展现出独特的横向轨道角动量特性,在光学微操纵、量子信息处理和光通信等领域具有重要的应用前景。本文针对空时涡旋场以及高阶空时结构电磁场的生成问题展开研究,结合严格耦合波分析电磁计算理论,成功产生了具有特定空时特性的空时涡旋场和混合空时涡环。主要内容包括三个部分。1.构建了一套基于严格耦合波分析的逆设计方法,阐述了严格耦合波分析的电磁计算理论,在此基础上,组合严格耦合波分析和伴随拓扑优化,实现了宽带系统的优化设计。2.研究了空时涡旋场的产生方法,实现了基于严格耦合波分析的空时涡旋场逆设计方法研究。系统介绍了空时结构电磁场的基本理论,重点阐述了其频谱分解方法,设计了基于拓扑荷的目标函数,组合严格耦合波分析和遗传算法设计了光子晶体板,产生了空时涡旋场。3.更进一步产生混合空时涡环,提出了利用逆设计超表面,并覆层环形径向极化天线阵,生成混合空时涡环的创新思路。完成了环形径向极化天线阵的设计,将其作为馈源,搭建了具有空时不可分离特性的混合空时涡环生成系统。本文构建的空时涡旋场及混合空时涡环生成方法体系,对这类新型空时结构电磁场在更多领域的研究和应用具有一定的理论指导意义和参考价值。更多还原

【Abstract】 Compared with the longitudinal orbital angular momentum(aligned parallel to the direction of light propagation)possessed by traditional vortex beams,the spatiotemporal optical vortex(STOV)field,as a novel spatiotemporal structured electromagnetic field,exhibits unique transverse orbital angular momentum characteristics,holding significant application prospects in optical micromanipulation,quantum information processing,and optical communications.This thesis focuses on the generation of spatiotemporal vortex fields and higher-order spatiotemporal structured electromagnetic fields,combining rigorous coupled-wave analysis(RCWA)electromagnetic computation theory to successfully generate spatiotemporal vortex fields and hybrid spatiotemporal vortex rings with specific spatiotemporal properties.The main content includes the following three aspects:1.A set of inverse design methods based on rigorous coupled-wave analysis was established.The electromagnetic computation theory of RCWA was elaborated,and on this basis,the combination of RCWA and adjoint topology optimization was employed to achieve the optimal design of broadband systems.2.The generation methods of spatiotemporal vortex fields were investigated,and an inverse design approach for spatiotemporal vortex fields based on RCWA was realized.The fundamental theory of spatiotemporal structured electromagnetic fields was systematically introduced,with a focus on their spectral decomposition methods.A target function based on topological charge was designed,and a photonic crystal slab was developed by combining RCWA with a genetic algorithm,successfully generating spatiotemporal vortex fields.3.Further,the generation of hybrid spatiotemporal vortex rings was explored.An innovative approach was proposed,utilizing inverse-designed metasurfaces layered over a circularly polarized antenna array to generate hybrid spatiotemporal vortex rings.The design of the circularly polarized antenna array was completed,serving as the feed source,and a hybrid spatiotemporal vortex ring generation system with spatiotemporally inseparable characteristics was constructed.The hybrid spatiotemporal vortex ring radiator was fabricated,tested,and analyzed,validating its performance in practical applications.The methodology system for generating spatiotemporal vortex fields and hybrid spatiotemporal vortex rings established in this thesis provides theoretical guidance and reference value for the research and application of such novel spatiotemporal structured electromagnetic fields in various domains.更多还原