Ab initio calculations of magnetic properties of Ag-doped GaN

We performed first-principles spin-polarized calculations to study the magnetic properties and electronic structure of AgxGa1−xN (x = 0.0556, 0.0625, and 0.125) using density functional theory (DFT) within a plane-wave ultrasoft pseudopotential scheme. We found a stable ferromagnetic state in Ag-doped GaN with a total magnetization of 1.81 μB per supercell, indicating that Ag is ferromagnetically ordered in GaN. These results imply that the ferromagnetic ground state originates from the hybridized Ag (4d)–N (2p)–Ga (3d)–N (2p) chain formed through p–d coupling. This study shows that 4d transition metals, such as, silver may also be used as ferromagnetic dopants in semiconductors.