新型磁流体光子晶体理论及传感技术研究

Magnetic fluid is a kind of nano-functional material. In recent years, the study on the optical properties of magnetic fluid has become the focus in the field of optoelectronics and sensor technology. Based on our earlier research work, it was found that when magnetic field applied perpendicularly to a magnetic fluid film exceeded a certain threshold, a hexagonal ordered chain structure was formed in the film. The distance between magnetic chains was in the degree of optical wavelength. According to this conclusion, a novel magnetic fluid photonic crystal was proposed. Compared with the traditional photonic crystals, it exhibited the advantages such as easy formation, simple facture process and better magnetic tunability. It would not only extend the application areas of photonic crystal but also become the foundation of a new type of photonic device. This project studied the theory and key technologies for magnetic fluid photonic crystal, including the microstructure, optical property and sensor technology. The molecular dynamic method based on rod-like shape was presented to simulate the growth process of magnetic fluid photonic crystal, and the magnetic tunability was analyzed. In addition, the experimental system was established. The magnetic field sensing system based on magnetic fluid photonic crystal cavity was designed. In addition, a novel sensor strcture and principle were proposed based on the SPR technology. This project is a forefront research topic in micro-nano sensing field. The contents proposed in this project are novel and innovative which have a great prospect and practical value.

磁流体是一种纳米功能材料，对其光学特性的研究是近年来光电和传感技术领域的热点。课题组在前期研究中发现，磁流体薄膜在磁场作用下，其微观结构表现出规则的六边形链状结构，且磁链间距在光波长量级。因此，本课题提出一种新型的磁流体光子晶体概念，它由封装在薄膜中的磁流体在一定的外加磁场作用下形成，与传统光子晶体相比制作过程简单，不需复杂的制备工艺，具有很好的磁调谐性。它的提出不仅扩展了光子晶体的种类，也可发展为一种新型的光电器件。本项目研究磁流体光子晶体的微观结构、光学特性和传感技术。提出基于球杆形的分子动力学方法，从微观角度模拟磁流体光子晶体形成过程、分析其磁调谐性、搭建实验系统；提出基于磁流体光子晶体微腔结构及结合表面等离子体共振技术的新型磁场传感系统。项目属于微纳传感技术领域的前沿性研究课题，具有明显的创新性、多学科交叉性和实际应用前景。

本项目从磁流体微观结构、光学特性和传感技术进行全面的研究，研究了磁流体光学特性研究载体FP结构的方案、封装工艺、磁流体填充技术，以此基础研究了基于磁流体的光纤传感结构的温度响应特性及温度补偿；还扩展了磁流体的光学特性、光纤传感方案的探索，如基于磁流体体积效应的熔接式高灵敏度法布里-珀罗光纤磁场传感器研究，小体积的超高磁场灵敏度的磁流体填充空芯光纤的磁场测量方法研究，基于模间干涉型的光纤微结构的高灵敏矢量磁场响应特性研究，新型的特种光子晶体光纤微传感结构的特性研究，基于C型光纤的高灵敏度和低损耗矢量磁场传感研究，基于非绝热锥形光纤的马赫曾德尔干涉仪光纤磁场温度双参数传感研究，基于磁流体填充环形WGM谐振器的光纤磁场传感研究等等，并针对信号解调的提出基于相位补偿技术的光纤双光束干涉信号的高精度光程差解调方案，大大提高解调精度和量程；项目执行期间获得众多的研究成果，具有明显的创新性、多学科交叉性。项目研究成果发表SCI收录文章18，授权专利8项；2020年，获批河北省自然科学二等奖1项。