First-principles prediction of electronic structure and magnetic ordering of rare-earth metals doped ZnO

The electronic structure and magnetism of RE (RE = La, Ce, Pr, Nd and Eu) doped ZnO are investigated by first-principles calculations. La doping can result in a diamagnetic ground state. The total magnetic moment of a single Ce, Pr, Nd and Eu doped ZnO are 0.92, 1.97, 3.01 and 6.82 mu(B) in a 2 x 2 x 2 supercell, respectively, followed by the appearance of spin splitting for initially O p and Zn s, d states at low energy range in the valence band and the localized magnetic influence of RE on ZnO. Doping of La and Ce is more stable than that of Pr, Nd and Eu. The ground states of Pr, Nd and Eu dopants at Zn sites are weakly antiferromagnetic, but the ground state of Ce dopants is ferromagnetic. Meanwhile, n-type doping is observed in Ce, Pr and Nd-doped ZnO systems as the donor states are near the conduction bands. (C) 2014 Elsevier B.V. All rights reserved.