Half-metallicity and structural properties of low-concentration Fe-doped SrS alloys: a first-principles study

Present research reveals the doping effect on physical properties of Sr1-xFexS by employing ab-initio calculations. The negative formation energy and optimization outcomes exhibit the stability of the Sr1-xFexS alloys with ferromagnetic phase. Spin dependent band structure (BS) and density of states (DOS) interpret that Sr1-xFexS revealed half metallic ferromagnetic (HMF) nature at 6.25% and 12.5% of Fe doping while metallic character is revealed at 25% concentration of dopant. Spin-up state of Sr0.9375Fe0.0625S and Sr0.8750Fe0.1250S depicts semiconductive behavior with bandgap value of 2.01/2.33 eV, correspondingly, while metallic in spin-down channel. The magnetism in the system is mainly originated because of Fe-d state that further confirmed from magnetic spin density. The total magnetic moments are 4.001, 7.9889, 16.0180 (µΒ) for 6.25%, 12.5% and 25% doping, respectively. Furthermore, optical features are investigated to explore the role of concentration on the response of alloys to incident light (0-10 eV). The ε1(0) value are 13.4, 26.9, 70.1 for Sr0.9375Fe0.0625S, Sr0.8750Fe0.1250S and Sr0.75Fe0.25S, respectively. The maximum absorption exists within of 3.4-7.89 eV for the studied compounds that make them suitable material for UV optoelectronic devices. Thus, the investigated alloys can be employed for spintronic and optical device usages.