Ti-doped AlN potential n-type ferromagnetic semiconductor: Density functional calculations

Using the full potential linearized augmented plane wave method, we calculate the magnetism and electronic structure for Ti-doped AlN. Calculations indicate the Ti can induce AlN a n-type ferromagnetic semiconductor. The shallower donor levels indicate the Ti-doped AlN can be easily ionized easily at working temperature. For the O and Ti co-doped AlN, calculations show ON defect may induce the magnetic moments increasing and also change Ti-doped AlN from semiconductor to metal. Compared to the conventional TMs-doped DMSs, Ti-doped AlN is free of ferromagnetic precipitate problems because compounds (TiN, AlN and TiAl) are not ferromagnetic.