Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1800195 | Journal of Magnetism and Magnetic Materials | 2013 | 4 Pages |
We report x-ray absorption spectroscopy (XAS) and x-ray magnetic circular dichroism (XMCD) measurements of both paramagnetic and ferromagnetic Ti1−xFexO2−δTi1−xFexO2−δ thin films. Fe L3,2L3,2 edge XAS spectra showed that the Fe ions in our samples were in mixed valence states and that the Fe2+/Fe3+ ratio decreased with increasing oxygen partial pressure. Finite XMCD signals were observed only for the Fe2+ state in the ferromagnetic sample. These findings indicate that the observed ferromagnetism in Ti1−xFexO2−δTi1−xFexO2−δ originates from ferromagnetic interactions between Fe2+ local spins.
► The Fe ions in Ti1−xFexO2Ti1−xFexO2 films are mixed valence states of Fe2+ and Fe3+. ► The valence state of Fe in Ti1−xFexO2Ti1−xFexO2 films systematically changes with PO2 during deposition. ► X-ray magnetic circular dichroism signals were observed only in ferromagnetic Ti1−xFexO2Ti1−xFexO2 film. ► The ferromagnetic interaction between Fe2+ local spins plays an essential role in Ti1−xFexO2Ti1−xFexO2.