First Principles Assessment of Electronic and Magnetic Properties of Fe and Ni Doped ZnO for Spintronic Applications

Presence of room temperature ferromagnetism (RTFM) is essential for the generation of new class of materials that have magnetic as well as semiconducting properties known as diluted magnetic semiconductors (DMSs). A 3d Transition metals (TMs) doping on DMSs improve their electrical, thermal and magnetic properties and also enhance their potentiality for the generation of emerging spintronic devices. Electronic and magnetic behaviors of, Fe and Ni doped ZnO were investigated using the density functional theory (DFT) with generalized gradient approximation and Hubbard on-site corrections (GGA+U). The results illustrated that pure and doped systems of ZnO have a direct bandgap. The calculated bandgap of pure ZnO is in agreement with the experimental findings while a decrease in bandgap found is due to the doping of Fe and Ni on ZnO, respectively. Total density of state (TDOS) plot illustrates that pure ZnO is diamagnetic, while Ferromagnetism was observed due to doping effect of Fe and Ni on ZnO. Results from Partial density of states (PDOS) shows that the asymmetric behavior of spin up and spin down on the d-electrons of Fe on ZnO are more compared to that of Ni on ZnO. Making it more promising candidate for spintronic applications.