Title :
Structure and Magnetism of Pure and Co-Doped TiO
Clusters
Author :
Wei, Xiao-Hui ; Skomski, Ralph ; Sellmyer, D.J.
Author_Institution :
Dept. of Phys. & Astron., Univ. of Nebraska, Lincoln, NE, USA
Abstract :
Anatase TiO2 cluster films having Co concentrations of 0, 6, and 8 at.% were produced by inert-gas condensation and investigated by TEM, AFM, XRD, and SQUID. The cluster films are all magnetically ordered from 10 to 400 K, with magnetizations of about 3 emu/cc, and exhibit perpendicular magnetic anisotropy. For 6% Co, no Co clusters or secondary phases are apparent, but the 8% samples contain Co and CoO. The magnetism of the doped and undoped samples is largely associated with oxygen vacancies which tend to form near the cluster surfaces.
Keywords :
SQUIDs; X-ray diffraction; atomic force microscopy; cobalt; doping profiles; perpendicular magnetic anisotropy; semiconductor doping; semiconductor thin films; semimagnetic semiconductors; titanium compounds; transmission electron microscopy; vacancies (crystal); wide band gap semiconductors; AFM; SQUID; TEM; TiO2:Co; XRD; anatase cluster films; dopant concentrations; inert-gas condensation; magnetization; oxygen vacancies; perpendicular magnetic anisotropy; temperature 10 K to 400 K; Dilute magnetic oxides; TiO$_{2}$; dilute magnetic semiconductors; magnetic moment; proteresis;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2009.2024762