First-principles study of silicon-doped nanotubesM. S. Si and D. S. Xue
Key Laboratory of Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University - Lanzhou 730000, PRC
received 28 March 2006; accepted in final form 20 September 2006
published online 13 October 2006
An ab initio calculation on the pristine and silicon-doped (5,5) boron nitride nanotube was performed. It was found that the silicon substitution for either a single boron or a single nitrogen atom in the (5,5) BN nanotube can induce spontaneous magnetization, and the local symmetry of the system is broken by the silicon atom extending outward of the tube. Calculations based on the 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 3p unpaired electron of silicon. Compared to other theoretical models of light-element or metal-free magnetic materials, the silicon-doped (5,5) BN nanotubes are more experimentally accessible and can be potentially useful.
73.22.-f - Electronic structure of nanoscale materials: clusters, nanoparticles, nanotubes, and nanocrystals.
81.07.De - Nanotubes.
75.50.Dd - Nonmetallic ferromagnetic materials.
© EDP Sciences 2006