Magnetic semiconducting anatase TiO2−δ grown on (100) LaAlO3 having magnetic order up to 880K

Anomalous Hall effect in sputter-deposited CoxTi1−xO2–δ films

“…Ferromagnetism in Cr-doped TiO 2 is reportedly induced by growth at lower oxygen pressure that induces oxygen vacancies [37]. Others have even reported ferromagnetism in reduced TiO 2 with no transition metal dopants [38][39][40], although this behavior for undoped material was not observed in the limited sample set considered in our study. It should be noted that ferromagnetism has been observed in insulating TiO 2 anatase in which the magnetic behavior was dependent on oxygen vacancies [41].…”

Room-temperature ferromagnetism in CuO sol–gel powders and films

“…They found that oxygen-annealing for In 2 O 3 , HfO 2 and SnO 2 films degraded magnetic moments sensitively and then proposed that both oxygen vacancies and confinement effects were key factors in introducing FM. Yoon et al [5] observed a high temperature FM in TiO 2 À d film and an increase of saturation magnetization with a decrease of oxygen pressure. Sundaresan et al [6] observed room-temperature FM in CeO 2 , Al 2 O 3 , ZnO, In 2 O 3 and SnO 2 nanoparticles, and presumed that room-temperature FM was due to the exchange interactions between localized electron spin moments resulting from oxygen vacancies at surfaces of nanoparticles.…”

Room-temperature ferromagnetism and ferroelectricity of nanocrystalline La2Ti2O7

“…The La 2 Ti 2 O 7 pellets annealed at T A = 1000 • C for 30 min and 1 h also present room-temperature FM. A typi- [17][18][19][20][21][22][23][24]28], the observed FM in nanocrystalline La 2 Ti 2 O 7 should originate from structural defects. By first-principle calculation, Mangalam et al suggested that the FM of nanocrystalline BaTiO 3 might come from the oxygen vacancies [28].…”

“…Undoped oxides, such as HfO 2 , TiO 2 , Al 2 O 3, In 2 O 3 , ZnO and MgO, have been found to exhibit weak FM at room temperature [17][18][19][20][21][22][23][24]. The observed FM may be related to the structural defects and size-confinement effects.…”