Influence of oxygen partial pressure on structural, transport and magnetic properties of Co doped TiO2 films

Crystal structure, transport and magnetic properties of Co dopedTiO2 laser ablated thin films are investigated and are found to have a strong dependence on the oxygen partial pressure. X-ray diffraction reveals the presence of mixed phase material containing anatase and rutile. However, these phases intertransform with the change in the oxygen partial pressure in the chamber during the growth of the films under the same temperature and other growth conditions. Electrical conductivity enhances as more oxygen vacancies are created. Concomitantly, the magnetization increases with increased vacancy concentration. The electrical transport data is suggesting that the conduction is dominated by polarons. The activation energies obtained are in the range from 100 to 150meV, typical for semiconducting oxides. APS Membership: Pending