基于表面等离激元的紧凑型多芯全光纤集成特种光束发生器

In this project, the aim is to explore compact multi-core all-fiber integrated special beam shaping devices based on surface plasmon polaritons. We plan to deposit metallic film onto the end face of a multi-core fiber, then fabricate air slits or quasi-periodic grooves microstructures near the fiber cores by use of the focused ion beam (FIB) technique. If the amplitude and phase of the decoupling light field satisfy that of the desired special beam, we can observe the overlap or the interference of multiple structured light in the free space, therefore two dimensional beam shaping device can be realized. We will design and realize wavelength multiplexing of special beam generator and further improve its integration. The mechanical characteristics of the light field in the beam shaping device will be studied and the beam shaping devices will be applied to capture microparticles. The proposed compact multi-core all-fiber integrated special beam shaping devices require no strict spatial collimation and coupling and can avoid the affect of oblique incident 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 beam shaping devices is important for us to have our own intellectual property, widely applied in microwave optics, in-fiber integrated optics and some related fields. Therefore, the project is very significant to develop novel fiber devices.

本项目旨在探索基于表面等离激元的紧凑型多芯全光纤集成特种光束发生器。拟在多芯光纤端面沉积金属膜，利用聚焦离子束刻蚀技术在各个纤芯附近金属表面制作缝和槽等微结构，使解耦合场的幅值和相位满足所需特种光束的分布规律，达到光场调控的目的，空间传输场将会是多束设计形状光束的相互叠加或干涉，进而获得二维空间拓展的光束发生器。设计并实现波长复用特种光束生成器，进一步提高其集成度。在此基础上我们将研究特种光束发生器光场的力学效应，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集成特种光束发生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，开展全光纤集成特种光束发生器的探索与研究，获得具有我国自主知识产权的光纤新器件，必将在纤维集成光学等相关领域获得更加广泛的应用，对于促进我国新型光纤器件技术的发展具有十分重要的意义。

本项目旨在探索基于表面等离激元的紧凑型全光纤集成特种光束发生器。本项目设计并实现了紧凑型多芯全光纤集成特种光束发生器。利用拉锥技术实现了单模光纤和多芯光纤的耦合及分束；利用纤端微结构实现了纤端集成Airy光束；利用抛磨技术将纤芯抛磨成斜面并覆盖金属周期结构实现了透射式表面等离激元传感；利用不同的多芯光纤和不同的微结构得到多光束叠加光场，详细分析了光场特性，并研究了二维网格光场的力学特性。双芯光纤光束偏折器在偏折角30°情况下可以将半径为50 nm的聚苯乙烯小球在距离纤端45 μm处稳定捕获，可以很好的实现远距离、多位置捕获。紧凑型多芯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14篇，其中被SCI收录9篇，邀请综述论文1篇，申请发明专利6项，获得授权3项。