Long-Range Surface Plasmon Resonance Hollow-Core Fiber Temperature Sensor With Ultrahigh Sensitivity

A long-range surface plasmon resonance temperature sensor based on hollow-core fiber inner coated with silicone resin and Ag films was proposed in this paper. The influence of structural parameters was investigated and optimized theoretically in the first. Then, two proposed sensors with different film thicknesses were fabricated and their performance in refractive index and temperature sensing were investigated experimentally. The experimental results agreed with the theoretical prediction. The fabricated sensor with 20 nm thick Ag film achieves a maximum temperature sensitivity of 29.43 nm/°C, which is higher than most optical fiber SPR sensors for temperature detection reported recently. The proposed sensor also maintains stability in repeated tests and has great potential in biomedical applications, environmental monitoring, and other fields.