Refractive index sensing based on photonic crystal fiber interferometer structure with up-tapered joints
Refractive index sensing based on photonic crystal fiber interferometer structure with up-tapered joints
复制标题
基于上锥接头光子晶体光纤干涉仪结构的折射率传感
DOI：
10.1016/j.snb.2015.06.148
复制
发表时间：
2015-12-31
影响因子：
8.4
通讯作者：
Yang, Yang
中科院分区：
文献类型：
--
作者：
Zhao, Yong;Li, Xue-gang;Yang, Yang
提出并实现了一种简单、超紧凑、高灵敏度的外折射率传感光子晶体光纤干涉仪(PCFI)。PCFI由两根单模光纤(SMF)之间的光子晶体光纤(PCF)拼接而成，纤芯偏移量较小。两个接头均为上锥形接头，采用熔融锥化技术制作，起到分模/合模的作用。马赫-曾德尔干涉仪(MZ1)包含了光子晶体光纤芯模和包层模之间的模间干涉。当ERI发生变化时，包层模式的RI会发生变化，输出干涉谱会发生漂移。通过测量干涉图的波长漂移，可以实现对温度不敏感的RI测量。此外，还对不同直径的光子晶体光纤的折射率传感特性进行了实验研究。实验结果表明，在折射率为1.333-1.379的范围内，其RI灵敏度可达252nmRIU。可以预见，如果PCF直径继续减小，RI敏感性可以得到改善。同时，该传感器具有结构简单、体积小、灵敏度高、成本低、温度灵敏度低等优点。(C)2015爱思唯尔B.V.保留所有权利。
A simple, ultra compact and highly sensitive photonic crystal fiber interferometer (PCFI) for external refractive index (ERI) sensing was proposed and demonstrated in this paper. The PCFI was formed by splicing photonic crystal fiber (PCF) between two single mode fibers (SMFs) with a slight core-offset. The both joints were up-tapered joints which acted as mode splitter/combiner and were made by fusion tapering technique. The Mach-Zehnder interferometer (MZ1) incorporated intermodal interference between core mode and cladding modes of the PCF. When the ERI changed, a RI variation of cladding modes would occur and the output interference spectrum would shift. By measuring the wavelength shift of the interference pattern, temperature-insensitive RI measurement could be achieved. In addition, the refractive index sensing properties with the different PCF diameters were also investigated experimentally. Experimental results showed that RI sensitivity could be up to 252 nm/RIU in the refractive index range of 1.333-1.379. And it could be anticipated that RI sensitivity could be improved if the PCF diameter continues to decrease. Meanwhile, the sensor had the advantages of simple structure, small size, high sensitivity, low cost and low temperature sensitivity. (C) 2015 Elsevier B.V. All rights reserved.