Half metallic ferromagnetism of Mn doped Alsb: A first principles study

We employ the spin-polarized, full potential linearized augmented plane wave (FLAPW) method within generalized gradient approximation (GGA) to study the electriconic and magnetic properties of Al1-xMnxSb (x = 0.25, 0.50, 0.75, and 1.0). We find that A(1-x)Mn(x)Sb is a half metal ferromagnet. The Fermi level shifts toward high energy with the increase of Mn concentration. At the end composition (i.e. MnSb) the Fermi level touches the conduction band edge and MnSb is nearly a half metal. The minority spin gap (similar to 1.0 eV) is robust to the change of Mn concentration. The total magnetic moment per Mn of Al1-xMnxSb is also (4.0 mu(B)) independent of the Mn concentration due to its half-metallicity. The induced magnetic polarization of the nearest Sb atom is antiparallel to that of Mn atom whereas parallel magnetic polarization is found at the Al site. (c) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.