Compact Magnetic Field Sensor Based on a Magnetic-Fluid-Integrated Fiber Interferometer

Abstract

A compact, low-cost, fiber-compatible magnetic field sensor based on multimodal interference in an S-taper and up-fusion-taper fiber modal interferometer is designed and experimentally demonstrated. The spectral characteristics in response to applied magnetic field and environmental temperature have been analyzed in detail. Experimental results indicate that the magnetic sensitivity reaches -0.03464 nm/Oe for a magnetic field ranging from 40 to 160 Oe. The proposed sensor has a maximum temperature sensitivity of 0.04889 nm/°C when the temperature increases from 27 to 45 °C. The effect of temperature on wavelength shift could be resolved by using a matrix containing the magnetic field and temperature sensitivities for two selected interferometric dips.