Abstract
We propose, to the best of our knowledge, a novel kind of tunable liquid crystal core refractive index (RI) sensor based on photonic crystal fiber (PCF) covered with a nanoring gold film. The finite element method is used to discuss and analyze the sensing performance of the RI sensor. Gold is used as the excitation material for surface plasmon resonance, and a gold nanoring is embedded around the first cladding of the PCF. The liquid analytes penetrate the outermost layer of the cladding, and the central hole is filled with liquid crystal E7. Complete coupling and incomplete coupling are excited as the analyte RI increases, and the resonance strength of complete coupling is stronger than that of incomplete coupling. It can be proved by calculation that at different wavelengths, resonant coupling of fifth-order and sixth-order surface plasmon polaritons is obtained. The RI of liquid analytes ranges from 1.405 to 1.445. The diameters of the liquid crystal cores are 0.2, 0.4, 0.6, and 0.8 µm; their average sensitivities are 10700, 10566, 10167, and 9166 nm/RIU; and the linear fitting constants are 0.98025, 0.97387, 0.96597, and 0.95507, respectively. In short, the RI sensor has the advantages of tunability, wide range, and high sensitivity, and is expected to be applied in various fields.
© 2022 Optica Publishing Group
Full Article | PDF ArticleMore Like This
Qianhe Zhao, Jin Liu, Haima Yang, Haishan Liu, Guohui Zeng, Bo Huang, and Jun Jia
Appl. Opt. 61(24) 7225-7230 (2022)
Doudou Wang, Yue Zhang, Yihan Qi, Jiangkun Tian, Shuai Yue, and Tian Ma
Appl. Opt. 61(22) 6664-6670 (2022)
Guowen An, Xiaopeng Hao, Shuguang Li, Xin Yan, and Xuenan Zhang
Appl. Opt. 56(24) 6988-6992 (2017)