Electronic structure and magnetic moments of 3d transition metal-doped ZnO

Ferromagnetism in 3d transition metal-atom-doped ZnO was investigated by ab initio electronic structure calculations based on the generalized gradient approximation (GGA). We also performed GGA+U calculations to further refine our results. We found that Mn-doped ZnO has the largest magnetic moment and Sc-doped ZnO is nonmagnetic. Also, Mn- Co- or Cu-doped ZnO are ferromagnetic semiconductors. For the other 3d transition metal atoms the doped ZnO are metals. The appearance of ferromagnetism in these systems suggests the possibility for fabrication of a transparent ferromagnet which may have a great impact on industrial applications in magneto-optical devices