Electronic structure of gadolinium complexes in ZnO in the GW approximation

The role of intrinsic defects has been investigated to determine binding energies and the electronic structure of Gd complexes in ZnO. We use density-functional theory and the GW method to show that the presence of vacancies and interstitials affect the electronic structure of Gd doped ZnO. However, the strong localization of the Gd-$f$ and $d$ states suggest that carrier mediated ferromagnetism in this material may be difficult to achieve.