Highly sensitive and stable probe refractometer based on configurable plasmonic resonance with nano-modified fiber core  

作　　者：Jianying Jing Kun Liu Junfeng Jiang Tianhua Xu Shuang Wang Tiegen Liu 

机构地区：[1]School of Precision Instruments and Opto-Electronics Engineering,Tianjin University,Tianjin 300072,China [2]Key Laboratory of Opto-Electronics Information Technology,Ministry of Education,Tianjin University,Tianjin 300072,China [3]Tianjin Optical Fiber Sensing Engineering Center,Institute of Optical Fiber Sensing,Tianjin University,Tianjin 300072,China

出　　处：《Opto-Electronic Advances》2023年第6期38-51,共14页光电进展（英文）

基　　金：financial supports from in part by National Natural Science Foundation of China under Grants 61922061, 61775161 and 61735011;in part by the Tianjin Science Fund for Distinguished Young Scholars under Grant 19JCJQJC61400

摘　　要：A dispersion model is developed to provide a generic tool for configuring plasmonic resonance spectral characteristics.The customized design of the resonance curve aiming at specific detection requirements can be achieved.According to the model,a probe-type nano-modified fiber optic configurable plasmonic resonance(NMF-CPR)sensor with tip hot spot enhancement is demonstrated for the measurement of the refractive index in the range of 1.3332-1.3432 corresponding to the low-concentration biomarker solution.The new-type sensing structure avoids excessive broadening and redshift of the resonance dip,which provides more possibilities for the surface modification of other functional nanomaterials.The tip hot spots in nanogaps between the Au layer and Au nanostars(AuNSs),the tip electric field enhancement of AuNSs,and the high carrier mobility of the WSe_(2)layer synergistically and significantly enhance the sensitivity of the sensor.Ex-perimental results show that the sensitivity and the figure of merit of the tip hot spot enhanced fiber NMF-CPR sensor can achieve up to 2995.70 nm/RIU and 25.04 RIU^(−1),respectively,which are 1.68 times and 1.29 times higher than those of the conventional fiber plasmonic resonance sensor.The results achieve good agreements with numerical simulations,demonstrate a better level compared to similar reported studies,and verify the correctness of the dispersion model.The detection resolution of the sensor reaches up to 2.00×10^(−5)RIU,which is obviously higher than that of the conventional side-polished fiber plasmonic resonance sensor.This indicates a high detection accuracy of the sensor.The dense Au layer effectively prevents the intermediate nanomaterials from shedding and chemical degradation,which enables the sensor with high stability.Furthermore,the terminal reflective sensing structure can be used as a practical probe and can allow a more convenient operation.

关 键 词：fiber photonics sensor customized plasmonic resonance curve nano-modified fiber core tip hot spot effect high sensitivity and stability 

分 类 号：O53[理学—等离子体物理] TP212[理学—物理]