Understanding Ferromagnetism In Carbon-Doped Rutile Tio2 : First-Principles Calculations

First-principles calculations based on density functional theory have been performed on the nonmagnetic 2p light element carbon-doped rutile TiO2, which is very appealing for spintronics and infranics. The results show that carbon dopants tend to couple ferromagnetically around the Ti atom in the ruble structure, and the magnetic moment per C is about 1.3 mu(B). The ferromagnetism is predicted to be the collective effects from a p-d exchange hybridization and a p-d exchange-like p-p coupling interaction, between the impurity (p-like t(2g)) and valence (p) states.