Computational Modeling of Optical Fiber-Based Magnetic Field Sensors Using the Faraday and Kerr Magnetooptic Effects

Abstract

Fiber-optic magnetic field sensors are attracting interest for applications in navigation, magnetic resonance, geophysics, space systems, power transformers, and generators, especially for harsh environments, at long distances, and for multiple monitoring points. This article presents a computational modeling for optical fiber-based magnetic field sensors using the magnetooptical Faraday and Kerr effects on the polar configuration. We propose two sensor profiles: one using a thin film of Fe and the other using a Ce:YIG layer. A simplified analytical model based on Fresnel equations is used to guide the numerical modeling built on COMSOL Multiphysics. The sensors' design methodology is also presented, which optimizes the sensor operating range and sensitivity. The proposed sensor sensitivity, resolution, and operating range are presented and compared to others found in the literature. The results indicate the possibility of building high-resolution sensors for a restricted range of magnetic field intensities or a wide-operating range sensor.