First-principles study on half-metallic ferromagnetism in the diluted magnetic semiconductor (DMS) Al1−xMnxP compounds

• The half-metallic ferromagnetism is stable for x≥0.0625.
• The half-metallic band gaps are about 1.5 eV.
• The Al1−xMnxPAl1−xMnxP (x=0.0, 0.0625, 0.125, 0.25) compounds are energetically stable.

We report the half-metallic properties of the Mn-doped AlP compounds using the full-potential linearized augmented plane wave (FPLAPW) method within the generalized gradient approximation (GGA) embedded in WIEN2k code. Geometry optimization for the Al1−xMnxP compounds was carried out for the different Mn concentrations x=0.0, 0.0625, 0.125 and 0.25 using supercell. The calculated band structure and density of states show that the half-metallic ferromagnetism is stable for the x=0.0625, 0.125 and 0.25 with a total magnetization of 4 µB/f.u. The total magnetic moment is mainly due to Mn-d states occurring around the Fermi level. The half-metallic band gaps are 1.70, 1.52 and 1.68 eV for x=0.0625, 0.125 and 0.25, respectively. We also performed GGA with the Hubbard correction (GGA+U) to minimize self-interaction errors.