二维光子晶体与光纤微纳集成结构的控光机理及其传感性能研究

With the advanced research on body area network technology, wearable and implantable monitoring devices for human health have emerged. As the core component for future sensor networks, integrated micro-and nano-sensors with ultra-compact footprints and high sensitivity could meet the requirements of accurately monitoring human health information in real-time. Recently, novel photonic crystal micro- and nano-sensors with high detection performance have attracted great attention due to high potential in system performance and advantages in device integration. The goal of this project is to realize high-performance integrated micro- and nano-sensors that combines optical fibers with two-dimensional photonic crystals. By calculating the band structure and the guided-mode characteristic of photonic crystals, coupled resonant phenomena between the guided-modes within light-cone and external radiation modes in the vertical direction of photonic crystals will be analyzed. Light-controlling mechanisms and sensing performance of the aforementioned optical sensing system will be studied. Then, the structural model of novel sensors based on fiber-integrated photonic crystals will be proposed and designed. By means of theoretical simulation and experimental test, the proposed novel sensor performance will be analyzed, evaluated and verified, which could provide a powerful reference for its application prospects and potential performance in the future sensor network.

随着体域网技术的研究深入，服务于人体健康的可穿戴、可植入监护设备已经出现，作为核心元件，超紧凑高灵敏度微纳集成传感器符合未来传感网络对人体健康信息进行实时性准确监测的应用需求。目前，新型光子晶体微纳传感器具备巨大性能潜力和集成优势，在高性能微纳感知检测应用研究领域备受关注。针对这一关键技术，本项目以二维光子晶体与光纤微纳集成结构为研究对象，从光子晶体能带结构和导模特性入手，重点分析位于能带结构光锥区域内的传导模式与光子晶体结构垂直方向上的辐射模式之间的耦合共振现象，深入研究二维光子晶体与光纤微纳集成结构的控光机理和传感机制。在此基础上，设计提出基于二维光子晶体与光纤微纳集成结构的新型传感器结构模型；并通过数值模拟仿真和实验测试，对其传感性能进行数值分析和评估验证，为新型光子晶体微纳传感器在面向未来传感网中的应用前景和性能潜力评价提供有力参考。

本项目针对微型化、超紧凑以及高灵敏度传感性能指标，研究处于前沿领域的基于光子晶体与光纤微纳集成结构的高性能微纳传感模型及其传感机理与传感性能。本项目的主要研究内容是以光子晶体与光纤微纳集成结构为研究对象，提出了一种可实现高反射、高品质因子（Q-factor）法诺共振现象的光子晶体与光纤集成传感器结构，重点研究分析了柱阵列光子晶体基本结构参数（例如：晶格常数、介质柱高度、柱半径等）和入射光波特性（例如：极化方式、入射角度）的对法诺共振传输特性的影响；掌握了透射谱/反射谱中Fano谐振波长和品质因数Q值随光子晶体结构参数的变化规律。在此基础上确定了可实现良好传输特性的柱阵列光子晶体结构参数，完成了相应的可实现高反射、高品质因子法诺共振现象的柱阵列光子晶体结构设计。通过进一步结构仿真优化，数值计算结果证实本项目所提出的柱阵列光子晶体结构法诺共振品质因子高达Q~5.2×10^4；而且，值得一提的是该优化结构使透射谱/反射谱中Fano谐振波长处可实现近100%的反射效应。该光子晶体法诺共振传感器被证实可以实现高性能感知，其中折射率灵敏度S=242nm/RIU，传感器的品质因数（FoM=Figure of Merit）~6.85×10^3，相对于之前的研究工作提升了一个数量级。本项目所提出的光子晶体与光纤集成传感器，其主要特点是结构简单、稳定性高、使用便携，能够实现高性能折射率传感。