Epitaxial ZnMnO/ZnO Coaxial Nanocable

Abstract

Zn0.96Mn0.04O/ZnO coaxial nanocables were prepared in two steps: ZnO nanowires were synthesized by standard thermal evaporation, followed by depositing Zn0.96Mn0.04 onto the surface of prepared ZnO nanowires using an ultrahigh-vacuum radio frequency magnetron-sputtering system. X-ray diffraction and X-ray photoelectron spectroscopy analysis reveal that Mn is incorporated well into the wurtzite ZnO without forming any Mn oxide. High resolution transmission electron microscopy images demonstrate that both ZnO and Zn0.96Mn0.04 layers are single-crystalline, and epitaxial growth is achieved between them, which predicts high carrier mobility and spin injection efficiency. Magnetic property measurements show that the Zn0.96Mn0.04/ZnO nanocables are ferromagnetic with a Curie temperature higher than 350 K.