D-shaped wide detection and high sensitivity dual-core photonic crystal fiber dual-parameter sensor

Abstract A dual-core photonic crystal fiber (PCF) with a wide detection range and high sensitivity was designed and analyzed for simultaneous measurement of temperature and changes in the refractive index (RI) of the analyte. The right core of the sensor measures temperature changes by exciting surface plasmon resonance (SPR) through PDMS and a gold layer, while the left core measures the RI by generating localized surface plasmon resonance (LSPR) with gold nanoparticles. When performing simultaneous dual-parameter measurement, the sensor faces the problem of cross-sensitivity. Usually, matrix demodulation is adopted to reduce interference. In this paper, a dual-core fiber was designed, and the spectra at different core positions were observed to measure the dual parameters, avoiding the cross-sensitivity crosstalk of dual parameters in single-core dual-parameter measurement. Through simulation optimization, the RI sensitivity of the sensor can reach 12,000 nm RIU −1 in the RI range of 1.09 to 1.42, and the temperature sensitivity is 26 nm °C −1 in the temperature range of 0 to 100 °C. The designed sensor has an extremely wide detection range and ultra-high sensitivity, and has broad application prospects in the fields of chemical production, biochemistry, environment, and medicine.