Zero-crosstalk ultra-high-sensitivity dual-parameter sensor for magnetic field and temperature based on polarization-maintaining photonic crystal fiber

It is found that enhancing the loss peak can effectively suppress crosstalk during detection of the magnetic field ( H ) and temperature ( T ). Polarization-maintaining photonic crystal fiber (PM-PCF) exhibits excellent immunity to crosstalk coupling due to its high birefringence effect. By combining these two characteristics, a dual-parameter sensor for magnetic field and temperature based on PM-PCF is proposed. The sensor’s prominent advantage lies in its breakthrough high-sensitivity characteristics and the first realization of zero-crosstalk sensing. By depositing a gold film on the inner walls of the air holes to excite the surface plasmon resonance phenomenon and filling magnetic fluid and polydimethylsiloxane as sensitive materials, the simultaneous detection of magnetic field and temperature is achieved. Numerical analysis demonstrates that within the ranges of 30–130 Oe for magnetic field and 26.5–30.5°C for temperature, the sensor exhibits a maximum magnetic field sensitivity of 67.35 nm/Oe and an average temperature sensitivity of 81.42 nm/°C. Compared with the current highest sensitivity, it still achieves a nearly twofold improvement. Additionally, this sensor has solved the crosstalk problem in dual-parameter sensors for temperature and magnetic field.