Theoretical and Experimental Investigation of an All-Fiber Waveguide Coupled Surface Plasmon Resonance Sensor With Au–ZnO–Au Sandwich Structure

• Main Authors: Jinying Ma, Kun Liu, Junfeng Jiang, Tianhua Xu, Shuang Wang, Pengxiang Chang, Zhao Zhang, Jiahang Zhang, Tiegen Liu
• Format: Article
• Language: English
• Published: IEEE 2019-01-01
• Series: IEEE Access
• Subjects: Surface plasmon resonance; optical fiber; waveguide coupled; sensitivity; refractive index sensing
• Online Access: https://ieeexplore.ieee.org/document/8911338/
• ISSN: 2169-3536

In this paper, we proposed an all-fiber waveguide coupled surface Plasmon resonance (SPR) sensor which was designed and fabricated with Au-ZnO-Au sandwich multi-layer structure. Based on the transfer matrix method (TMM), the theoretical modeling of the proposed sensor structure was investigated. The influence of the layer thickness on the transmission spectrum of the sensor was studied numerically, in order to optimize each layer thickness, leading to sensitivity enhancement in the infrared spectral range. Meanwhile, an experimental testbed for the refractive index measurement was implemented based on the proposed all-fiber waveguide coupled SPR sensor. Using this waveguide coupled SPR sensor, the refractive index sensing was realized with a sensitivity enhancement of 7%-131% compared with conventional SPR sensors.