强聚焦矢量光场的高精度调控及其纳米级全面表征方法研究

Tightly focused vectorial optical field could break the limitations of traditional optical systems and finds applications in many areas, such as super-resolution microscopy, optical micromanipulation, optical data storage, etc. The research into tightly focused vectorial optical field has become one of the hottest topics in optics. Aiming to solve the critical problems in engineering precision and comprehensive characterization of highly focused vectorial optical fields, this project devotes to establish and improve the theory and methods to engineer and characterize the focused optical field through the development of a three-dimensional spatial distribution customization model of tightly focused vectorial optical field, a comprehensive model of influencing factors, a nano-scale full characterization method for the focused field, and a fast optimization algorithm for engineering precision control. We will solve these key technical problems by employing high resolution two-dimensional liquid crystal spatial light modulator (SLM) to build a closed-loop system for focal field engineering. Experiments will be conducted to validate the adopted theoretical and technical approaches. The research of this project is of great significance in revealing the principle of using liquid crystal SLM to control each degree of freedom of the focused field, clarifying the interaction mechanism between the focused field and nanoparticles, analyzing the influence of the internal and external factors on the engineering precision of the focal field, and elucidating fast adaptive methods for high-dimensional optimization problems. The ultimate goals of this project are to achieve high precision control of the tightly focused vectorial optical field and its nano-scale comprehensive characterization, laying the theoretical and technical foundation for future practical applications.

强聚焦矢量光场能突破传统光学系统的限制，被广泛应用于超分辨显微成像、光学微操纵、光信息存储等领域，成为当下光学研究的热点之一。针对其调控精度差及表征困难关键问题，本项目拟研究强聚焦矢量光场三维空间分布定制模型、影响因素综合模型、纳米级焦场全面表征手段、调控精度快速优化算法，建立和完善焦场调控及表征的理论体系与方法；突破关键技术，基于高分辨率二维液晶SLM搭建焦场调控闭环系统，对所获得的理论和技术成果进行实验验证。通过本项目的研究，揭示液晶SLM对焦场各个自由度的调控机理，阐明焦场与纳米粒子相互作用机制，剖析内外部因素对焦场调控精度的影响过程，阐述高维优化问题自适应快速求解方法，实现对强聚焦矢量光场的高精度调控及纳米级全面表征，为其推广应用提供理论和技术支撑，具有重要的科学意义。

强聚焦场能够突破传统光学系统的限制，显著提高光学系统的性能，被广泛应用于光学检测、光信息存储、谐波生成、高分辨显微成像、光学微纳加工、光镊等领域，成为当前光学领域研究的热点之一。本项目围绕强聚焦场的高精度调控及表征这一核心问题，开展了焦场调控及表征方法系统建模及实验验证、光场调控精度自适应优化方法和新型时空光场调控三个方面的研究，形成的研究成果主要包括：基于偶极天线辐射理论的激光焦场定制模型，多参量可调的亚波长焦斑对的生成及表征，动态定制表面等离激元中的光学斯格明子，对称弧缝结构中的表面等离激元干涉条纹移动及其在瑞利金属粒子俘获中的应用，超手性光场的产生方法，亚波长尺度内具有纯横向轨道角动量的时空涡旋的生成方法，定制结构光中的光子角动量的模型，强聚焦圆偏振时空涡旋中的自旋轨道相互耦合效应，用于受激发射损耗纳米光刻的双光束共轴输出的耦合装置和方法，基于米散射理论的强聚焦场的表征模型，矢量光场发生器实验系统，矢量光场生成过程中实现精确幅度调制的快速迭代方法，时空涡旋的闭环自动三维表征系统，紧凑型矢量光场发生器中4f系统的对齐方法，横向轨道角动量的生成方法及其超高速调控，柱矢量时空涡旋的生成及表征，光子轨道角动量三维调控，传播不变的贝塞尔时空光涡旋，基于啁啾脉冲的时空光场映射调控技术。上述研究成果进一步丰富了光场调控的基础理论和技术手段，揭示并实验验证了光场调控中新的自由度，为矢量光场的推广应用提供了坚实的理论和技术支撑，具有重要的科学意义。本项目在国内外学术期刊发表及录用研究论文18篇，其中，SCI收录英文源刊16篇(包括一区论文6篇，二区论文4篇)，EI收录国内核心期刊1篇；申请国家发明专利6项，已授权4项。此外，关于时空光场调控的研究成果入选美国光学学会评选的2020年度全球30项重大光学进展。