Magnetism modulation of Fe/ZnO heterostructure by interface oxidation

Abstract

In this study, the magnetic coercivity (Hc) of Fe/ZnO heterostructure was significantly enhanced by 2–3 times after applying a suitable current. This Hc enhancement originates from the Fe-oxidation at the Fe/ZnO interface induced by direct current heating. Depth-profiling X-ray photoemission spectroscopy analysis confirmed the formation of FeO, Fe3O4, and Fe2O3 close to the interface region, depending on the Fe thickness and annealing process. This study demonstrates that direct current heating can moderately change the local interface oxidation and modulate the magnetic properties. These results clearly reveal the correlation between magnetism and interface properties in the Fe/ZnO heterostructure and provide valuable information for future applications.