First-principles study of magnetic properties of the cobalt doped silver copper sulfide

First principles calculations in the framework of density functional theory have been carried out to study the electronic and magnetic properties of cobalt (Co) doped silver copper sulfide (AgCuS) system. Cobalt doped at Cu site can induces a significant amount of magnetism in AgCuS. The total and partial density of states reveal that 3d orbital electron of the Co atom is the primary source of magnetism and the rest of magnetic moment comes from the 3d orbital electron of Cu atoms. Spin-spin interaction study suggests a ferromagnetic ordering with Ruderman-Kittel-Kasuya-Yoshida (RKKY) type of exchange interaction. The spin polarized density of states calculation suggest the presence of polarized density of states at the Fermi level which makes the system more interesting as a half-metallic ferromagnetic system.