Study of different magneto-optic materials for current sensing applications

This article discusses the properties of different diamagnetic and paramagnetic materials for a basic current/magnetic field sensor system set up with different relative orientations of analyzers and polarizers. The paper analyzes linearity ranges of different materials and their sensitivity for different wavelengths. Terbium doped glass (TDG), terbium gallium garnet (TGG), doped TGG and dense flint glass materials are used for analysis based on Faraday's rotation principle. TGG shows high Faraday rotation, temperature stability and high optical quality. Three ranges of the magnetic field have been chosen for performance analysis. The study reveals that doping of praseodymium (Pr3+) on TGG exhibits a better response at 532 nm as well as 1064 nm wavelengths than TGG. At 632.8 nm wavelength, cerium (Ce3+) doped terbium aluminum garnet (TAG) ceramic exhibits better resolution than others. The study has been done for performance analysis of different MO sensors applicable for measurement of various process parameters like current, displacement, and magnetic field.