Wavelength dispersion of Verdet constant in E-field oriented iron oxide doped polymer nanocomposites

The wavelength dispersion of Verdet constant was evaluated for nanoparticulate hematite (α-Ferric Oxide) and maghemite (γ-Ferric Oxide) in poly-phenyl methyl vinyl siloxane after the nanoparticles were oriented using an external electric field. The experiment was carried out at wavelengths of 405 nm, 473 nm, 532 nm and 632.8 nm. The role of electric field based orientation of the nanoparticles in affecting the Faraday rotation was studied and found to directly improve the signal to noise ratio for magneto-optic sensing. The purpose of this experiment was to evaluate the material for potential applications as an optical current sensor in a magneto-optic current transformer for accurate measurement and highly enhanced magneto-optic sensitivity. The highest Verdet constant observed was 7.91 °/ T-cm for hematite doping, measured at a wavelength of 532 nm for an applied electric field of 2.5 kV/cm.