Simultaneous Measurement of Magnetic Field and Temperature Utilizing Magnetofluid-Coated SMF-UHCF-SMF Fiber Structure

We have proposed and experimentally demonstrated a dual-parameter optical fiber sensor for simultaneous measurement of magnetic field and temperature. The sensor is a magnetofluid-coated single-mode fiber (SMF)-U-shaped hollow-core fiber (UHCF)-single-mode fiber (SMF) (SMF-UHCF-SMF) fiber structure. Combined with the intermodal interference and the macro-bending loss of the U-shaped fiber structure, the U-shaped fiber sensor with different bend diameters was investigated. In our experiments, the transmission spectra of the sensor varied with magnetic field strength and temperature around the sensing structure, respectively. The dip wavelengths of the interference spectra of the proposed sensor exhibit red shifts with magnetic field strength and temperature, and the maximum sensitivity of magnetic field strength and temperature were 1.0898 nm/mT and 0.324 nm/°C, respectively.