Structural, electronic and optical properties of Zn0.5Cr0.5S from first-principles.

The structural, magnetic, electronic and optical properties of the Zn 0.5 Cr 0.5 S ZB , Zn 0.5 Cr 0.5 S W and Zn 0.5 Cr 0.5 S RS are studied by spin-polarized first-principles calculation. After optimization Zn 0.5 Cr 0.5 S ZB system changes its original cubic structure of ZnS ZB to a tetragonal structure, while Zn 0.5 Cr 0.5 S W and Zn 0.5 Cr 0.5 S RS still remain their original hexagonal structure of ZnS W and tetragonal structure of ZnS RS , respectively. The total moments of these Cr doped ZnS systems are mainly contributed by local magnetic moments of Cr 2+ ion. Zn 0.5 Cr 0.5 S ZB , Zn 0.5 Cr 0.5 S W and Zn 0.5 Cr 0.5 S RS are all half-metal with 100% spin polarization. The Zn 0.5 Cr 0.5 S W has the biggest static dielectric constant ɛ 1 (0) and refractive index n (0). The Zn 0.5 Cr 0.5 S ZB , Zn 0.5 Cr 0.5 S W and Zn 0.5 Cr 0.5 S RS have tow absorption regions in the ranges of 0–27 eV and 41–55 eV, but the absorption width decreases for Zn 0.5 Cr 0.5 S W , Zn 0.5 Cr 0.5 S ZB and Zn 0.5 Cr 0.5 S RS successively. The results will give a guide for design and application of the Zn 0.5 Cr 0.5 S ZB , Zn 0.5 Cr 0.5 S W and Zn 0.5 Cr 0.5 S RS in spintronic devices and optical detectors. [ABSTRACT FROM AUTHOR]