Dilute magnetic semiconductors based on wide bandgap SiO2 with and without transition metal elements

Material designs based on the first principle calculations of electronic structures are proposed for α-quartz SiO₂-based dilute magnetic semiconductors. The incorporation of transition metals (TMs) into Si sites and of the non-TM atoms into O sites are treated for various concentrations. At temperatures higher than room temperature, most of the TM-doped SiO₂ have no magnetism, yet Si_1−xMn_xO₂ might achieve the ferromagnetism. The substitution of O by non-TM atoms as C or N also induces the magnetism in the host. However, while the N's substitution induces the ferromagnetism, C's substitution causes an anti-ferromagnetic behavior in the host material SiO₂.