Gd impurities effect on $$\hbox {Co}_{2}\hbox {CrSi}$$ Co 2 CrSi alloy: first-principle calculations

Abstract

First-principle calculations have been performed to study Gd impurities doping effect on the physical properties of the Heusler half-metallic ferromagnet \(\hbox {Co}_{2}\hbox {CrSi}\) using the density functional theory in the local spin density approximation with an additional Hubbard correlation term for the rare-earth 4f states. The results show that the gadolinium moment is aligned antiparallel to that of transition metal atoms for both \(\hbox {Co}_{16} \hbox {Cr}_{7} \hbox {GdSi}_{8}\) and \(\hbox {Co}_{15}\hbox {GdCr}_{8}\hbox {Si}_{8}\). The analysis of the doped material band structures shows that the half-metallic properties are completely conserved if Gd substitutes Cr atoms, while the minority-spin gap is filled and half-metallicity is lost when Gd substitutes Co atoms.