Micro-structured optical fiber magnetic field sensor based on magnetic fluid filling

A novel micro-structured fiber magnetic field sensor based on magnetic fluid (MF) filling is proposed. The air hole radius in the cladding of fiber is reduced from inner layer to outer layer, and the numerical analysis is performed by the finite element method (FEM). For the [Formula: see text]-pol mode, the proposed sensor has an average sensitivity of 960.61 pm/Oe, and for the [Formula: see text]-pol mode, the average sensitivity can reach 884.85 pm/Oe. The sensor has the advantages of small size and high sensitivity and is competitive in magnetic field sensors.