Thin films of Ni-doped anatase on SiO2 substrates were fabricated by reactive magnetron sputtering. Doping and annealing effects upon structure and magnetism were systematically investigated. The results showed that ferromagnetism originated from the doped matrix, and that enhancement (suppression) of ferromagnetism was strongly correlated with an increase (decrease) in O vacancies.

Oxygen Vacancy Enhanced the Room Temperature Ferromagnetism in Ni-Doped TiO2 Thin Films. Hou, D.L., Meng, H.J., Jia, L.Y., Ye, X.J., Zhou, H.J., Li, X.L.: Physics Letters A, 2007, 364[3-4], 318-22