title: Surface magnetism of Mg doped AlN: a first principle study.
abstract: Using first-principles calculations, we have systematically investigated the magnetic properties of Mg-doped AlN (1 0 1 0) and (0 0 0 1) surfaces. Both the polar and non-polar surfaces are found to be magnetic and the magnetic moments are mainly due to spin polarized 2p orbitals of surface N atoms surrounding Mg. The splitting of energy levels in both cases favours charge hopping between the minority spin states of N 2p orbitals, which leads to a stable ferromagnetic ground state. However, the range of magnetic coupling and the stability of the ferromagnetic state differ between the polar and non-polar surfaces and are dependent on the nature of localization of the defect states. The ferromagnetic state in a Mg-doped reconstructed (0 0 0 1) surface is more stable than in a Mg-doped AlN (1 0 1 0) surface.
authors.affiliation: Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117551.
authors.forename: Sandhya
authors.initials: S
authors.lastname: Chintalapati
authors.forename: Ming
authors.initials: M
authors.lastname: Yang
authors.forename: Shu Ping
authors.initials: SP
authors.lastname: Lau
authors.forename: Yuan Ping
authors.initials: YP
authors.lastname: Feng
mesh_terms: D017607:Aluminum Compounds / Q000737:chemistry*; D003198:Computer Simulation; D008274:Magnesium / Q000737:chemistry*; D008280:Magnetics; D008958:Models, Molecular; D013499:Surface Properties
chemical_list: D017607:Aluminum Compounds; C052045:aluminum nitride; D008274:Magnesium