全介质多芯光纤纤端集成光场调控器件研究

In this project, the aim is to explore compact lab-on-tip light manipulation device integrated in multicore fibers based on all-dielectric resonators. We plan to deposit high-index dielectric film onto the end face of a multi-core fiber, then fabricate subwavelength microstructures with quasi-periodic grooves in the vicinity of the fiber cores by use of the photolithography technique. High-precision 3D printing technique is utilized to directly print low-index material microstructure. If the amplitude and phase of the output light field satisfy that of the desired special beam, we can observe the overlap or the interference of multiple structured beams in the free space, therefore two dimensional beam shaping device can be realized. Further, dynamic light modulation can be achieved by incorporating nonlinear material. On the basis of the above results, we study mechanical effects of integrated light manipulation devices and attempt to capture microparticles. The proposed lab-on-tip light manipulation devices require no strict spatial collimation and coupling and can avoid affects of oblique incidence on device performance. The devices have many advantages including high integration, flexible operation, system stability and strong anti-interference capability, etc. The study of all-fiber integrated light manipulation devices is important for us to have our own intellectual property, widely applied in microwave optics, in-fiber integrated optics, nanophotonics and nonlinear optics. Therefore, the project is very significant to develop novel fiber devices.

本项目旨在探索基于全介质谐振机理的紧凑型多芯光纤纤端集成光场调控器件。拟在多芯光纤端面沉积高折射率介质膜，利用微纳光刻技术在各个纤芯附近介质膜表面制作亚波长微结构，而对于低折射率对比的材料则采用高精度3D打印技术直接刻写微纳结构，使出射光场的幅值和相位满足所需特殊光场的分布规律，达到光场调控的目的，空间传输光场将会是多束不同光束的相互叠加或干涉，进而获得二维空间拓展的光场调控器件。利用非线性材料设计并实现动态可调光场调控器。在此基础上研究集成光场调控器件的力学效应，并将其应用到微粒子捕获中。项目提出的紧凑型多芯全光纤纤端集成光场调控器件不需要严格的空间准直、耦合光路，避免入射光倾斜入射对器件性能的影响，具有集成度高、操作灵活、系统稳定和抗干扰能力强等特点。因此，开展全光纤集成光场调控器件的探索与研究，获得具有自主知识产权的光纤新器件，对于促进我国新型光纤器件技术的发展具有十分的重要意义。

本项目计划目标基本实现，设计并实现了紧凑型多芯全光纤集成特种光束发生器，并对该纤端微结构进行了理论仿真计算和力学特性分析，达到预期目标。利用拉锥技术实现了单模光纤和多芯光纤的耦合及分束。围绕全介质周期结构与光纤技术的结合，在多模、单芯和多芯光纤端面设计亚波长金属或介质微结构，实现了多种纤端集成光场调控器件，包括热光可调的聚焦光束、轴向多焦点光束、多偏折光束等，获得了二维空间拓展的特种波前发生器，并研究了其力学特性。利用双芯光纤与微球结合实验上实现了粒子不同方位的捕获，并利用双芯光纤成功地实现了高阶模的高效率转换。同时研究了利用非线性材料来动态调控光波赝自旋等手性特性。紧凑型全光纤集成特种光束发生器将极大的缩小现有光束整形器件的尺寸，这种光纤集成特种光束生成器件不需要严格的空间准直、耦合光路，消除入射光倾斜入射对器件性能的影响，具有集成度高、结构微小、操作灵活、系统稳定和抗干扰能力强等特点。推动该类器件向实用转化又迈进了一步。基于本项目研究的成果已经以专利及论文的形式体现，共发表论文学术论文20篇，其中被SCI收录14篇，会议论文5篇，邀请综述论文1篇，邀请报告2次；申请发明专利6项，获得授权3项。