He Jia, Zhang Fengchan, Xu Xizhen, Du Bin, Wu Jiafeng, Li Zhuoda, Bai Zhiyong, Guo Jinchuan, Wang Yiping, He Jun
Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education/Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China.
Shenzhen Key Laboratory of Photonic Devices and Sensing Systems for Internet of Things, Guangdong and Hong Kong Joint Research Centre for Optical Fibre Sensors, Shenzhen University, Shenzhen 518060, China.
Polymers (Basel). 2022 Sep 1;14(17):3617. doi: 10.3390/polym14173617.
High-accuracy temperature measurement plays a vital role in biomedical, oceanographic, and photovoltaic industries. Here, a highly sensitive temperature sensor is proposed and demonstrated based on cascaded polymer-infiltrated Mach-Zehnder interferometers (MZIs), operating near the dispersion turning point. The MZI was constructed by splicing a half-pitch graded index fiber (GIF) and two sections of single-mode fiber and creating an inner air cavity based on femtosecond laser micromachining. The UV-curable polymer-infiltrated air cavity functioned as one of the interference arms of MZI, and the residual GIF core functioned as the other. Two MZIs with different cavity lengths and infiltrated with the UV-curable polymers, having the refractive indexes on the different sides of the turning point, were created. Moreover, the effects of the length and the bending way of transmission SMF between the first and the second MZI were studied. As a result, the cascaded MZI temperature sensor exhibits a greatly enhanced temperature sensitivity of -24.86 nm/°C based on wavelength differential detection. The aforementioned result makes it promising for high-accuracy temperature measurements in biomedical, oceanographic, and photovoltaic applications.
高精度温度测量在生物医学、海洋学和光伏产业中发挥着至关重要的作用。在此，基于级联聚合物浸润马赫-曾德尔干涉仪（MZI）提出并演示了一种高灵敏度温度传感器，其工作在色散转折点附近。该MZI通过拼接半节距渐变折射率光纤（GIF）和两段单模光纤，并基于飞秒激光微加工创建内部空气腔而构建。紫外光固化聚合物浸润的空气腔作为MZI的一个干涉臂，剩余的GIF纤芯作为另一个干涉臂。创建了两个具有不同腔长且浸润有紫外光固化聚合物的MZI，其折射率位于转折点的不同侧。此外，还研究了第一个和第二个MZI之间传输单模光纤的长度和弯曲方式的影响。结果，基于波长差分检测的级联MZI温度传感器表现出极大增强的温度灵敏度，为-24.86 nm/°C。上述结果使其在生物医学、海洋学和光伏应用中的高精度温度测量方面具有广阔前景。
