三光束干涉型微纳光纤光子器件与液态电光/磁光介质耦合结构的全光纤电磁场传感机理研究

A new type of all-fiber electric/magnetic field sensing mechanism is proposed in this project. The sensor combines the special light transmission properties of three-beam interferometric microfiber photonic device (IMPD) and electro-optical/magneto-optical effect of electro-/magneto-optical liquid (EOL/MOL) to form an IMPD-EOL/MOL sensing structure. The project will focus on the fundamental theory and key technologies involved in the proposed sensing technology, which include: Investigating the sensing mechanism of the proposed sensor, reveal the intrinsic mechanism of transmission spectral fringe shifting with applied electric/magnetic field; Finding the main factors which have great impact on sensing performance and conducting in-depth study of the operation principle of these factors, then sum up an effective way to improve the sensing performance; Studying the dependence of transmission spectral characteristics on ambient temperature variation, from which to find out the method to eliminate the cross-sensitivity of temperature; On the basis of the above research， exploring the optimal fabrication and package technology and setting up electric/magnetic synchronized sensing system. The project is expected to explore and realize an all fiber electric/magnetic field sensor with compact structure, high sensitivity, temperature intrinsic insensitive, laying technical foundations for the simultaneously measurement of electric field and magnetic fields in one sensing system. The results of this project pave a new wat to break through the existing bottlenecks in the area of optical sensing technology such as complex structure, low sensitivity, temperature cross-sensitivity, etc. It also provides essential theoretical guidelines to further expand microfiber based photonic devices in the applications sensing area.

项目将三光束干涉型微纳光纤光子器件（IMPD）和液态电光/磁光介质（EOL/MOL）独特的电学、磁学、光学特性进行有机地结合，提出一种基于IMPD-EOL/MOL耦合结构的新型电磁场传感机理，并围绕其基础理论和关键技术展开研究：研究IMPD-EOL/MOL传感机理，揭示被测电磁场对传感器传输光谱特征的影响规律；研究影响传感器传感性能的机制及主要因素，探索提高传感性能的有效途径；研究环境温度对光谱特征的影响规律，探索环境温度不敏感型光纤电磁场传感技术的实现途径；探索传感器的最优制备与封装工艺，组建电磁场一体化测量系统。研究成果为突破现有光学电磁场传感技术中存在的结构复杂、灵敏度低、温度交叉敏感、电磁场无法一体化测量等关键瓶颈问题奠定理论基础，对丰富微纳光纤光子器件的种类、拓展微纳光纤在传感领域中的应用具有重要意义。

本项目提出以特种功能光纤干涉结构取代传统传感器结构中分立光学器件，以形成全光纤电磁场传感器的技术思路，避免了分立元件之间对准、耦合等带来的传感器结构不稳定、性能低劣等问题，同时使传感器的尺寸大为减小；深入研究了传感器产生振铃现象的机理，提出抑制振铃现象的有效措施；系统研究了环境温度、系统噪声对传感器输出的影响机理及规律，提出提高传感器工作稳定性的新方法；针对脉冲电场持续时间短、波前陡的特点，设计了低噪声、高增益、高带宽的传感信号快速解调系统，实现了对超快空间电场信号的捕获。在理论与关键技术的研究基础上，实际制作出全光纤电磁场传感器并研制出传感测试系统原型机（微秒脉冲和纳秒脉冲通用），传感系统测量范围覆盖0.08～1000kV/m（点场）、100A/m～5000A/m（磁场），系统响应频带覆盖50Hz～400MHz。