Magnetic and half-metallic properties of Cr-doped β-SiC

Using ab initio ultrasoft pseudopotential plane wave method, the effect of Cr doping concentration on the magnetic properties of β-SiC (SiC:Cr) was investigated quantitatively. It is found that the total magnetic moment of SiC:Cr is independent of the substitution site and amount of doping concentration. Using the density of states calculation, it is shown that SiC:Cr has half-metallic properties for selected doping concentrations of 1.56%, 3.13%, and 6.25%, irrespective of substitution site. The conduction electron mobility of SiC:Cr_C was expected to be higher than that of SiC:Cr_Si. On the contrary, SiC:Cr_Si has a wider spin band gap compared to SiC:Cr_C. It is predicted that SiC with 6.25% Cr doping represents desirable characteristics for realizing spintronic devices. These include half-metallic properties, high electron mobility, and a wide spin band gap with the Fermi level located at the center of the gap.