First-principles calculations were used to investigate the roles of the silicon vacancy (VSi) and nitrogen impurity in the magnetic properties of silicon carbide (3C-SiC). High-spin configurations were predicted for the negatively-charged (VSi) defects. The coupling was ferromagnetic between the (VSi) defects at −2e charge state, whereas the (VSi) defects at -e charge state prefer to interact antiferromagnetically. Substituting C with N atoms could manipulate the charge states of (VSi) defects and the magnetic interactions between them. This work offered a possible route towards high Curie-temperature ferromagnetism in metal-free 3C-SiC materials.

Ferromagnetic Ordering of Silicon Vacancies in N-Doped Silicon Carbide. M.Zhao, F.Pan, L.Mei: Applied Physics Letters, 2010, 96[1], 012508