Fiber optic magnetic field sensor with wide range based on magnetic fluid refractive index tunability

In this paper, an optical fiber magnetic field sensor based on the magnetic fluid refractive index tunability is proposed. A magnetic field sensor-sensitive unit was manufactured, and an experimental test platform was established for performance testing and analysis. Simulation analyzes the influence law of fiber spacing on the mode field's distribution. The proposed optical fiber magnetic field sensor can measure the magnetic field strength in the range of 0-1.7 T, which has the advantages of an extensive dynamic range, excellent sensitivity, a simple structure, and low production cost. The optical fiber magnetic field sensor proposed in this study can be used in the superconducting system's quenching monitoring system to ensure the system's safe and reliable operation.