Magnetism and structure of anatase (Ti1-xVx)O2 films

Anatase TiO2 is known as a promising host material for a wide-gap ferromagnetic semiconductor as it is a good solvent for numerous transition-metal elements. We report on the structural and magnetic properties of epitaxially grown anatase (Ti1-xVx)O2 layers where x covers the whole range of solubility of V atoms in anatase TiO2 and beyond the solubility limit of 21%. We measured an average magnetic moment per vanadium as high as 1 µB with a magnetic percolation threshold of less than 6% which agrees with recent theoretical predictions. Interestingly, our results show a decrease of the average V magnetic moment as x increases throughout the solubility range. Anatase (Ti1-xVx)O2 is no longer present beyond the solubility limit, where the nonmagnetic VO2 phase forms and destroys the net magnetization