Design of a coated thinly clad chalcogenide long-period fiber grating refractive index sensor based on dual-peak resonance near the phase matching turning point  

作　　者：齐倩玉 李耀威 刘婷 张培晴 戴世勋 徐铁峰 Qianyu Qi;Yaowei Li;Ting Liu;Peiqing Zhang;Shixun Dai;Tiefeng Xu(Laboratory of Infrared Material and Devices,Advanced Technology Research Institute,Ningbo University,Ningbo 315211,China;Key Laboratory of Photoelectric Detection Materials and Devices of Zhejiang Province,Ningbo 315211,China;Engineering Research Center for Advanced Infrared Photoelectric Materials and Devices of Zhejiang Province,Ningbo University,Ningbo 315211,China;Ningbo Institute of Oceanography,Ningbo 315832,China)

机构地区：[1]Laboratory of Infrared Material and Devices,Advanced Technology Research Institute,Ningbo University,Ningbo 315211,China [2]Key Laboratory of Photoelectric Detection Materials and Devices of Zhejiang Province,Ningbo 315211,China [3]Engineering Research Center for Advanced Infrared Photoelectric Materials and Devices of Zhejiang Province,Ningbo University,Ningbo 315211,China [4]Ningbo Institute of Oceanography,Ningbo 315832,China

出　　处：《Chinese Physics B》2023年第1期327-333,共7页中国物理B（英文版）

基　　金：Project supported by the Natural Science Foundation of China (Grant Nos.62075107,61935006,62090064,and62090065);K.C.Wong Magna Fund in Ningbo University。

摘　　要：A novel method for designing chalcogenide long-period fiber grating(LPFG) sensors based on the dual-peak resonance effect of the LPFG near the phase matching turning point(PMTP) is presented. Refractive index sensing in a high-refractive-index chalcogenide fiber is achieved with a coated thinly clad film. The dual-peak resonant characteristics near the PMTP and the refractive index sensing properties of the LPFG are analyzed first by the phase-matching condition of the LPFG. The effects of film parameters and cladding radius on the sensitivity of refractive index sensing are further discussed. The sensor is optimized by selecting the appropriate film parameters and cladding radius. Simulation results show that the ambient refractive index sensitivity of a dual-peak coated thinly clad chalcogenide LPFG at the PMTP can be 2400 nm/RIU, which is significantly higher than that of non-optimized gratings. It has great application potential in the field of chemical sensing and biosensors.

关 键 词：chalcogenide longperiod fiber grating dual-peak resonance phase matching turning point refractive index sensor 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]