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Ferromagnetism at 300 K in spin-coated anatasea and rutile Ti0.95Fe0.05O2 films

R. Suryanarayanan·V. M. Naik·P. Kharel·P. Talgala·R. Naik
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Abstract

Thin films of Ti1-xFexO2 (x=0 and 0.05) have been prepared on sapphire substrates by spin-on technique starting from metal organic precursors. When heat treated in air at 550 and 700 degrees C respectively, these films present pure anatase and rutile structures as shown both by X-ray diffraction and Raman spectroscopy. Optical absorption indicate a high degree of transparency in the visible region. Such films show a very small magnetic moment at 300 K. However, when the anatase and the rutile films are annealed in a vacuum of 1x10-5 Torr at 500 degrees C and 600 degrees C respectively, the magnetic moment, at 300 K, is strongly enhanced reaching 0.46 $μ$B/Fe for the anatase sample and 0.48 $μ$B/Fe for the rutile one. The ferromagnetic Curie temperature of these samples is above 350 K.

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R. Suryanarayanan, V. M. Naik, P. Kharel, P. Talgala, R. Naik. 2004-10-14. Ferromagnetism at 300 K in spin-coated anatasea and rutile Ti0.95Fe0.05O2 films. https://doi.org/10.1088/0953-8984%2F17%2F4%2F017

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