1. Ferromagnetism in nanocrystalline epitaxial Co:TiO2 thin films.
- Author
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Pradhan, A. K., Hunter, D., Dadson, J. B., Williams, T. M., Zhang, Kai, Lord, K., Lasley, B., Rakhimov, R. R., Zhang, Jun, Sellmyer, D. J., Roy, U. N., Cui, Y., Burger, A., Hopkins, C., Pearson, N., and Wilkerson, A. L.
- Subjects
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FERROMAGNETISM , *NANOCRYSTALS , *EPITAXY , *THIN films , *PULSED laser deposition , *ATOMIC force microscopy - Abstract
We report on the observation of remarkable room-temperature ferromagnetism in nanocrystalline epitaxial Co:TiO2 films grown on sapphire (0001) substrates by a pulsed-laser deposition technique using high-density targets. The films were characterized by x-ray measurements, atomic force microscopy, micro-Raman, electron-paramagnetic resonance, and magnetization studies. The films exhibit three-dimensional islandlike growth that contains nanocrystalline particles. Our experimental results suggest that the remarkable ferromagnetism in Co:TiO2 films is controlled either by the interstitial Co2+ ions or small clusters, which are mainly present at the interface and on the surface of the films. Our work clearly indicates that Co interstitials and nanoclusters cause room-temperature ferromagnetism in Co-doped TiO2. [ABSTRACT FROM AUTHOR]
- Published
- 2005
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