Electronic and magnetic properties of ZnS doped with Cr

Materials with an isolated partially filled intermediate band are of great interest as new materials for high-efficiency solar cells, as up- and down-converters, and midinfrared lasers with low nonradiative decay because of the properties of this band. This intermediate band is only present in some compounds, such as a ZnS host semiconductor uniformly doped with Cr. The study presented in this work is based on the substitutional doping of Cr by Zn with atomic concentrations of 3.125%. We use first principles with the local density approximation. To improve the description of the localized states a screened Coulomb interaction has been applied. From the results, it was found that these materials have a partially filled intermediate band for both ferromagnetic and antiferromagnetic spin alignments. The addition of a Hubbard term from 0  to  9  eV shows a greater stability of the ferromagnetic spin order and an increase in the intermediate bandwidth.

©2006 The American Physical Society