Ab Initio Study of Structural, Electronic, and Magnetic Properties of A 1 − x III $\mathrm {A}_{1-x}^{\text {III}}$ Mn x BVI: In1−x Mn x S-Diluted Magnetic Semiconductor

Abstract

First-principles density functional calculations on the new class of diluted magnetic semiconductor $A_{1-x}^{III}{Mn}_{x}B^{VI}$ In1−x Mn x S for x = 0.25 and 0.5 are investigated to study the structural, electronic, and magnetic properties, employing the full-potential linearized augmented plane wave method. Electronic band structures and density of states revealed a half-metallic character of In1−x Mn x S and show the stability of anti-ferromagnetic states as compared with ferromagnetic states. The calculated exchange constants J dd are in good agreement with experimental and theoretical results on magnetic properties of single crystalline $\mathrm {A}_{1-x}^{\text {III}}{\text {Mn}}_{x}\mathrm {B}^{\text {VI}}$ in the anti-ferromagnetic case. Our predicated calculations on the s,p-d exchange constants N 0 α and N 0 β show that they are lower than in $\mathrm {A}_{1-x}^{\text {II}}{\text {Mn}}_{x}\mathrm {B}^{\text {VI}}$ DMS. The local environment is found tetrahedral as in the II–VI DMS and other (III,Mn) VI compounds. The total magnetic moment for In1−x Mn x S for different concentrations is in accordance with the exact value 5 μ B and comes mainly from impurity Mn. The local magnetic moments of Mn ions are reduced from their free space charges values due to the p-d hybridization which produces small magnetic moments on the nonmagnetic In and S sites. The Curie temperature of In1−x Mn x S is calculated within the mean field approximation and compared with other DMS systems.