The Electronic and Magnetic Properties of Ultrathin γ-Fe2O3 Films

Abstract

In this work, iron oxide γ-Fe2O3 films with thickness of 10 nm were grown on a single crystalline MgO (001) substrate by molecular beam epitaxy using oxidation of an iron thin film at substrate temperature 250 °C. The crystal structure, electronic, and magnetic properties of the ultrathin epitaxial γ-Fe2O3 films were investigated. X-ray photoemission spectroscopy, Low energy electron diffraction, and X-ray diffraction confirmed that films were single crystalline quality with the same orientation as the MgO substrates and had only a single phase of γ-Fe2O3. Furthermore, the magnetization measurements at 300 K showed that the ultrathin films were ferromagnetic with a magnetization value of 270 emu cm-3. These results show that it is possible to synthesize high-quality ultrathin γ-Fe2O3 films with good properties, which are promising as a spin filtering tunnel junction and for application in other spintronic devices, using the iron oxidation method.