Dai Bin, Shen Xiang, Hu Xiongwei, Yang Luyun, Li Haiqing, Peng Jinggang, Li Jinyan
Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China.
Sensors (Basel). 2019 Aug 30;19(17):3749. doi: 10.3390/s19173749.
A Mach-Zehnder interferometer (MZI) based on an etched all-solid microstructure fiber (MOF) has been demonstrated. The MZI works on the basis of interference between the vibrant core and cladding modes in the MOF. The all-solid MOF has a heterostructure cladding composed of Ge-doped rod arrays and pure silica, and thus can support and propagate a vibrant cladding mode with a large mode area. When the outermost cladding of MOF is etched, the cladding mode becomes sensitive to the ambient refractive index (RI). The etched MOF can work as a sensing head for RI sensing. By comparing the interference spectra, the extinction ratio has remained stable at around 20 dB after the MOF was etched. The RI sensing characteristics of the MZI with an etched MOF have also been investigated. The results show that the RI sensitivity can reach up to 2183.6 nm/RIU with a low-temperature coefficient (<10 pm/°C).
一种基于蚀刻全固态微结构光纤（MOF）的马赫-曾德尔干涉仪（MZI）已得到验证。该MZI基于MOF中活跃的纤芯模式与包层模式之间的干涉原理工作。全固态MOF具有由掺锗棒状阵列和纯二氧化硅组成的异质结构包层，因此能够支持并传播具有大模场面积的活跃包层模式。当MOF的最外层包层被蚀刻时，包层模式对环境折射率（RI）变得敏感。蚀刻后的MOF可作为用于RI传感的传感头。通过比较干涉光谱，在MOF被蚀刻后，消光比在20 dB左右保持稳定。还研究了带有蚀刻MOF的MZI的RI传感特性。结果表明，RI灵敏度可达2183.6 nm/RIU，且温度系数较低（<10 pm/°C）。
