Exchange Constants N0β Research Articles

An ab-initio calculation of half-metallic ferromagnetism in vanadium doped ZnS

In the current study, the structural, electronic and magnetic properties of Zn1-xVxS (at x = 0.125 and 0.25) have been investigated using full-potential linearized augmented plane wave plus local orbital (FP-LAPW + lo) method within the density functional theory (DFT). The Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA) has been applied for optimizing the structural properties. The electronic and magnetic properties were studied by both PBE-GGA and modified Becke and Johnson local spin density approximation (mBJ-LSDA). Results show that the Zn1-xVxS (at x = 0.125 and 0.25) structures are more stable in the ferromagnetic phase. The density of states and band structure calculations reveal that these compounds exhibit half metallic character with 100% spin polarization at the Fermi level. The energy gap in the minority spin channel increases with an increase in concentration of doping. The values of p–d exchange splitting ΔEv and p–d exchange constants N0β are negative, which confirms that the effective potential is more attractive for the minority spin states. Also, it is found that exchange constants N0α and N0β decreases with the increasing concentration of vanadium, which confirms the ferromagnetic character of these compounds. The calculated total magnetic moments for Zn1-xVxS are about 3 μB largely arisen from the vanadium doping.