Magnetism of Zn0.75Cr0.25S with ordered doping configurations predicted by generalized gradient approximation plus Hubbard U

Abstract

We applied the first-principles method with empirical Hubbard U parameters to study the magnetism of Zn0.75Cr0.25S with the varied doping configurations. Depending on the doping configurations, calculations using generalized gradient approximation (GGA) methods with and without U were compared to study the electronic structure and magnetic properties of Zn0.75Cr0.25S. Simulation with GGA method confirms the presence of ferromagnetic ordering in Zn0.75Cr0.25S as is theoretically concluded by previous literature work, while calculations with GGA+U methods predict either antiferromagnetic or ferromagnetic ordering depending on the doping configurations. The appearance of magnetic ordering is rationalized in terms of the coupling between two adjacent doping Cr atoms that primarily governs the magnetic ordering. Therefore, changing the coupling chains in the Cr-containing semiconductors may provide an alternative route to tune the magnetic properties.