Faraday Effect for Magnetic Sensitivity Measurement in Different Types of Optical Fibers

Khorsheed, Suha; Abdulla, Roaa T; Al-Azzawi, Zeena M; Al-Dulaimi, Wasan A

doi:10.22075/ppam.2026.41285.1230

Faraday Effect for Magnetic Sensitivity Measurement in Different Types of Optical Fibers

Document Type : Original Article

Authors

Suha Khorsheed

Roaa T Abdulla

Zeena M Al-Azzawi

Wasan A Al-Dulaimi

Department of Physics, College of Science, Al-Nahrain University, Baghdad, Iraq

10.22075/ppam.2026.41285.1230

Abstract

This research explores the Faraday effect in optical fibers and its exploitation to enhance the sensitivity of magnetic field measurements using fiber Bragg grating technology. The aim is to develop a more efficient magnetic sensor by modifying the traditional Faraday experiment and replacing the conventional optical fiber with a multi-grid Bragg fiber. A modified experimental setup was designed using an infrared laser and Bragg fibers with varying numbers of gratings (from one to four regions), and the effect of current intensity and spacing between the electrodes on the magnetic field strength was investigated. The results showed that the magnetic field increases linearly with the current, and the optimal field distribution is achieved at an average spacing between the coils. Furthermore, the results indicated that increasing the number of gratings leads to increased sensitivity due to the amplification of the Faraday effect and the extension of the effective length of the optical interaction. The four-segmented fiber exhibited a sensitivity of 93 w/T higher than the conventional fiber, although an optimal limit to the number of gratings was noted, as excessive grating leads to signal loss and response saturation. It has been observed that the change in magnetic response depends primarily on polarization rotation rather than wavelength shift, due to the small value of the Verdet constant in silica at a wavelength of 1550 nm. This has made the use of multi-segment Bragg fibers an effective approach for improving the performance of magneto-optical sensors, with the potential for development into high-precision electromagnetic measurement applications.

Keywords

Optical fibers

Fiber Bragg grating

Verdet constant

Magnetic sensors

Subjects

Optical Materials

© 2026 The Author(s). Progress in Physics of Applied Materials published by Semnan University Press. This is an open access article under the CC-BY 4.0 license. (https://creativecommons.org/licenses/by/4.0/)

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