Optimization Research of Er-doped Magneto-refractive Photonic Crystal Fiber Based on Surface Plasmon Resonance

Abstract

In order to meet the demand for large-scale magnetic field testing, this paper proposes a D-shaped magneto-refractive photonic crystal fiber (MRPCF) based on surface plasmon resonance (SPR) by using the erbium-doped material. By varying the diameter, location, and number of layers of the air holes, the four different Models A, B, C, and D structures are created, and the corresponding magnetic field sensing properties are analyzed. The simulation findings demonstrate that the magnetic field sensitivities of Models A, B, C, and D are 28 pm/mT, 48 pm/mT, 36 pm/mT, and 21 pm/mT, respectively when the magnetic field strength is 5 - 405 mT. Meanwhile, the figure of merit (FOM) of the four MRPCF-SPR sensors is investigated, which have FOMs of 4.8×10-4 mT-1, 6.4×10-4 mT-1, 1.9×10-4 mT-1, 0.9×10-4 mT-1. Model B has high sensitivity and large FOM. It shows that altering the structural design of the fiber can significantly improve the magneto-refractive effect of MRPCF. The proposed MRPCF has numerous uses in the areas of geological research, earthquake and tsunami monitoring, and military navigation. It can also be expected to enable quasi-distributed magnetic field sensing.