Design and Analysis of Surface Plasmon Resonance Sensor with Open-Loop Side-Polished Photonic Crystal Fiber.

A novel open-loop photonic crystal fiber (PCF) refractive index sensor based on the surface plasmon resonance effect is proposed. The gold film is applied to the surface of the air-core PCF to induce the SPR effect. The finite element method is employed to examine the influence of open-angle on the sensing performance. Simulation results show that the sensor is suitable for refractive index measurements ranging from 1.26 to 1.32 when the open-angle ranges from 90 to 130°, demonstrating an average wavelength sensitivity of 1738 nm/RIU. As the angle varies from 140 to 180°, the sensor becomes more appropriate for refractive index measurements ranging from 1.32 to 1.38, displaying an average wavelength sensitivity of 1667 nm/RIU. The sensing range of the sensor is influenced by open-angle, enabling the selection of an appropriate sensor structure according to the desired measurement range. [ABSTRACT FROM AUTHOR]