Magnetic Properties of Rutile Ti1-xFexO2 Epitaxial Thin Films

Growth conditions for pulsed laser deposition of ferromagnetic Ti1-xFexO2 films with the rutile structure have been optimized on the basis of magnetooptical Kerr effect (MOKE) measurements. Thus, it was found that Ti0.94Fe0.06O2 films prepared under very limited growth conditions, at a substrate temperature of 650–675°C and an oxygen pressure of ~1 ×10-6 Torr, show ferromagnetism at room temperature. The optimized films revealed a saturation magnetization of 1.3 µB and a coercive field of 0.14 kOe. From XPS measurements, the valence state of Fe was determined to be 3+, ruling out the possibility that ferromagnetism may arise from Fe3O4 nanoparticles.