Magnetism in BN nanotubes induced by carbon doping

We performed ab initio calculation on the pristine and carbon-doped (5,5) and (9,0) BN nanotubes. It was found that carbon substitution for either a single boron or a single nitrogen atom in the BN nanotubes can induce spontaneous magnetization. Calculations based on density functional theory with the local spin density approximation on the electronic band structure revealed a spin polarized, dispersionless band near the Fermi energy. The magnetization can be attributed to the carbon 2p electron. Compared to other theoretical models of light-element or metal-free magnetic materials, the carbon-doped BN nanotubes are more experimentally accessible and can be potentially useful. (C) 2005 American Institute of Physics.