Oxygen-defect-induced magnetism to 880 K in semiconducting anatase TiO2-Dd films

We demonstrate a semiconducting material, TiO2-D*d, with ferromagnetism up to 880 K, without the introduction of magnetic ions. The magnetism in these films stems from the controlled introduction of anion defects from both the film-substrate interface as well as processing under an oxygen-deficient atmosphere. The room-temperature carriers are n-type with n~3 X 1017 cm-3. The density of spins is ~1021 cm-3. Magnetism scales with conductivity, suggesting that a double exchange interaction is active. This represents a new approach in the design and refinement of magnetic semiconductor materials for spintronics device applications.