Magnetic and electrical characterization of TiO2 single crystals co-implanted with iron and cobalt

Single-crystals of TiO2 rutile were co-implanted with iron and cobalt to investigate the combined role of these ions in the magnetic properties of the system. The implantations were carried out using an energy of 150 keV and different fluences to investigate their influence in the magnetic and electrical properties of the implanted samples. For the higher fluences the as implanted single crystals exhibit superparamagnetic behaviour associated with the formation of nanosized magnetic aggregates. Annealing treatments were performed at 673 K and 1073 K, inducing recovery of the lattice structure and the evolution of the formed phases. Iron and cobalt play different roles in the implanted region, the presence of iron inhibiting the formation of cobalt aggregates during annealing at 1073 K.