Dual-parameter sensor for refractive index and temperature sensing based on surface plasmon resonance

In this paper, alcohol solution is added into the center hole of PCF-SPR sensor to realize the dual parameter sensor of temperature and refractive index (RI) simultaneously. Firstly, the external temperature is fixed at 20 °C, and the RI of the alcohol solution is changed. The resonance wavelength sensitivity is -6015.4 nm/RIU and the linearity is 0.99985 when the RI of alcohol solution is from 1.34 to 1.3654 with a resonance-loss sensitivity of -2640 dB/RIU and a linearity of 0.99475, respectively. When the concentration of alcohol solution is fixed at 70.4% and the external temperature of PCF is changed, the resonance loss sensitivity is 1.0375 dB/°C and the linearity is 0.976 when the external temperature is changed between 20 °C and 80 °C, its resonance loss sensitivity is 2.4219 nm/°C and the linearity is 0.9997. Finally, the sensor matrix of temperature and refractive index with respect to the shift of resonant wavelength and the change of resonant loss is obtained.