Pulsed laser deposited films of Co-doped anatase (formula presented) are examined for Co substitutionality, ferromagnetism, transport, magnetotransport, and optical properties. Our results show limited solubility (up to ∼2%) of Co in the as-grown films and formation of Co clusters thereafter. For the (formula presented) sample, which exhibits a Curie temperature (formula presented) over 1180 K, we find the presence of 20–50 nm Co clusters as well as a small concentration of Co incorporated into the remaining matrix. After being subjected to the high-temperature anneal during the first magnetization measurement, the very same sample shows a (formula presented) and almost full matrix incorporation of Co. This (formula presented) is close to that of as-grown (formula presented) sample (∼700 K). The transport, magnetotransport, and optical studies also reveal interesting effects of the matrix incorporation of Co. These results are indicative of an intrinsic (formula presented) diluted magnetic semiconductor with (formula presented) of about 650–700 K.
|Original language||English (US)|
|Number of pages||1|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - 2003|
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics