Абстрактный

A Comparative Study of Spin Magnetic Moment, Spin Polarization and Curie Temperature of Heusler Type Compounds (A2-x-y Zy)MnZ (A=Ni, Pd, Pt and Z=Sb, Sn)

M Shahjahan*, SC Roy, MJ Sadique

The Heusler type compounds (A2-x-yZy)MnZ (A=Ni, Pd, Pt; Z=Sb, Sn; x=1, 0; and y=0, antisite defects of Z atoms) are investigated to under-stand the induced magnetic properties. The structural phases C1b type half Heusler (x=1, y=0) compounds AMnZ and the corresponding L21 type full Heusler (x=y=0) compounds A2MnZ and some disordered compounds (A1-yZy)MnZ and (A2-yZy)MnZ were calculated using the Korringa-Kohn- Rostoker Green’s function method. The antisite doping of 1% (5%) Sb re-tain (suppressed) the half metallicity at (Ni1-ySby)MnSb, whereas the other compounds were found to be gapless in both spin directions. Density of states at the fermi level exhibit the explicit spin polarization of the compounds. The net magnetic moments of the compounds are closer in their values, wherein the manganese atom is responsible for the major contribution of magnetic moments, which is enough larger than the partial moment of other constituents. The Curie Temperature (TC) of the ordered ferromagnetic compounds was estimated using the mean field approximation. The TC higher than the room temperature was found for the ordered compounds, except for the cases of Pt2MnSb and Pt2MnSn. No literature value of TC is reported yet for these two compounds. Calculated spin moments and TC agree well with the available experimental results.