Effect of p-d hybridization on half metallic properties of some diluted II-IV-V2 chalcopyrites for spintronic applications

Based on the ab initio electronic structure calculations performed by Korring-Kohn-Rostoker method combined with the coherent potential approximation, the effect of transition metals impurities on the electronic states and magnetic properties of ZnXAs2 (X = Sn, Ge) chalcopyrites has been investigated. Electronic density of states, Curie temperature T-C, ferromagnetic (FM), antiferromagnetic (AF) and spinglass-like (DLM) energies and their variation as well as crystal field splitting energy Delta(CF) and exchange interactions Delta(e) and Delta t(2) are all discussed in detail. The analysis of the densities of states of Zn(Sn, TM)As-2 and Zn(Ge, TM)As-2 shows that these compounds exhibit half-metallic character and high-spin ferromagnetic state. The importance of different exchange mechanisms like double exchange, ferromagnetic and antiferromagnetic super-exchange in Zn(Sn, TM)As-2 and Zn(Ge, TM)As-2 chalcopyrites is also discussed. The result as derived in this report shows that V- and Cr-doped ZnSnAs2 and ZnGeAs2 chalcopyrites exhibit a stable ferromagnetic half metallic state, whereas Fe-doping manifests antiferromagnetic and spinglass-like states. These results make Zn(Sn, TM)As-2 and Zn(Ge, TM)As-2 chalcopyrites useful for spintronic applications.