Investigation of half-metallic ferromagnetism in Ti-doped BeS DMS compound: A promising spintronic material

摘要

The first principles calculationshave been performed to calculate the electronic and magnetic properties of Be_(1-x)Ti_xS (x=0.03 and 0.06) Diluted Magnetic Semiconductor (DMS) compound using full potential linearized augmented plane wave (FPLAPW) method based on density functional theory (DFT). The estimatedresults show that the substitution of Ti-dopant at the cation (Be) site alters the ground state properties of host BeS compound significantly and the resultant compounds becomes true half metallic (HM) ferromagnet. This behavior is due to the hybridization of S-p states with Ti-d states at/near E_F which introduces a gap in minority spin channel with 100% spin polarization at E_F. The resultant compounds at both dopant concentrations have band gap at the Fermi level (E_F) for only one spin channel and showing metallic property for other spin channel which is desired feeeature for spintronic applications. The Ti-doping in BeS induces a net magnetic moment of ～2.0 μ_B which shows an important role played by Ti-d states in total magnetic moment. The half metallic character of Ti-doped BeS makes it as promising material for spintronic devices.