Extraordinary Hall effect and ferromagnetism in Fe-doped reduced rutile

Abstract

Room-temperature ferromagnetism is observed in reduced rutile TiO 2Ϫ␦ by Fe doping. The epitaxial films grown by pulsed-laser deposition are carefully examined by x-ray diffraction, transmission electron microscopy, and magnetic and transport measurements. The films exhibit the extraordinary Hall-effect and thin-film magnetic shape anisotropy. The magnetic moments and anticipated Curie temperatures of the films rule out Fe particles, iron oxides, and Ti-Fe oxides as possible sources for the observed magnetic signals. The carriers of the Fe-doped reduced rutile are p-type, with a carrier density of 1ϫ10 22 /cm 3. This room-temperature dilute magnetic semiconductor should find potential applications in spintronics.

Co-occurrence of Superparamagnetism and Anomalous Hall Effect in Highly Reduced Cobalt-Doped RutileTiO2−δFilms

“…Only recently, different groups including ours, observed the AHE in highly reduced rutile TiO 2 films doped with either Fe or Co, raising optimism about the possibility of an intrinsic nature of ferromagnetism therein [11][12][13]. This situation clearly calls for detailed magnetic and microstructural studies of these films to establish or refute the premise of a strict connection between the AHE and the intrinsic nature of DMS ferromagnetism.…”

Room-temperature ferromagnetism in Mn and Fe codoped In2O3

“…Many materials have been found, which could be considered as good candidates for DMS applications. [2][3][4][5][6] However, due to the small solubility of magnetic ions in the host semiconductor, ferromagnetism in some cases is attributed to the clusters of dopants formed during the sample preparation procedure. [7][8][9] Therefore, new diluted magnetic semiconductors based on host semiconductors with high solubility of transition metal ions are highly desirable.…”

Magnetic Oxide Semiconductors

“…V-doped anatase TiO 2 was reported to be ferromagnetic at room temperature [129]. Fe-doped rutile TiO 2 was reported to be ferromagnetic over room temperature [130][131][132][133] and to show anomalous Hall effect at room temperature [131,132]. Fe-doped anatase TiO 2 was reported to be ferromagnetic at room temperature [134,135].…”