Magneto-optical properties of iron oxide films

Iron oxide films have been grown onto MgO and oxidized silicon substrates using pulsed laser deposition with a 248 nm excimer laser. The films were deposited in a vacuum from an α-Fe2O3 target. Films grown epitaxially on MgO consisted of the ferrimagnetic γ-Fe2O3 phase, with an average saturation magnetization of 353±26 kA/m. The Faraday rotation of the γ-Fe2O3 films was measured at 645 nm and 1550 nm wavelengths, and was found to be 4 and 2.5 degrees/μm, respectively. It is assumed that the high Faraday rotation, accompanied by a relatively high absorption, is associated with a transition of Fe2+ ions in octahedral sites.