Multiparameter photonic crystal fiber-based plasmonic sensor for refractive index, magnetic field, and temperature

A photonic crystal fiber (PCF) sensor is proposed for the detection of refractive index (RI), magnetic field intensity, and temperature. The large air hole in the center of the sensor is filled with a magnetic fluid (water-based Fe3O4) whose RI changes with the intensity of the magnetic field and temperature. The top of the sensor is polished and coated with gold film, and external sensing technology is used to detect changes in the RI of the analyte. Due to the characteristics of the structure, the lower and upper parts of the sensor can detect magnetic field intensity, temperature, and RI. The simulation results show that the proposed magnetic field, temperature, and RI sensitivities of the sensor can reach the maximum of 1.57 nm/Oe, −1 nm / ° C, and 7600 nm/RIU in the detection range of 22 to 250 Oe, 8°C to 60°C, and 1.38 to 1.42 RIs, respectively. The proposed multiparameter PCF plasmonic sensor can be used for hyperthermia monitoring, medical and chemical sample analysis, biomolecular engineering, and magnetocardiography.