High-Sensitivity SPR Temperature Sensor Based on Hollow-Core Fiber

A biocompatible and robust fiber surface plasmon resonance (SPR) temperature sensor was fabricated based on an alcohol-filled hollow-core fiber. The fabrication process of this designed sensor included Ag film coating, liquid injection, and fusion splicing, which was low cost and efficient. Due to the high refractive index sensitivity of the SPR effect and the high thermal optical coefficient of alcohol, the designed sensor performed well in temperature sensing, whose linear sensitivity reached as high as 1.16 nm/°C in the range of 35.5 °C-70.1 °C. Being small in size, low in fabrication cost, and highly sensitive in performance, this sensor is suitable for temperature detection during biological and chemical reactions and has the potential to realizing multiparameter or distributed temperature measurement.