PCF based surface plasmon resonance temperature sensor with ultrahigh sensitivity

A simple photonic crystal fiber (PCF) temperature sensor with high sensitivity based on the principle of surface plasmon resonance (SPR) is proposed. The cladding of the sensor is mainly composed of two layers of square arranged holes. The inner wall of the outer air holes is selectively plated with gold film, and the outer holes are filled with the temperature sensitive material chloroform to promote the coupling of the surface plasmon mode and the fundamental mode, thereby improving the sensitivity. The finite element method is used to analyze the effects of the temperature on the performance of the sensor. Through tailoring the structural parameters, it is shown that the maximum sensitivity of the sensor can reach up to − 10.4 nm/℃ in the range of 0–60 ℃ with high resolution and good linearity. Such appealing characteristics make the sensor be one of the important potential candidates in the field of temperature sensing.