Oxygen vacancy effects on electronic structure of Pt/NiO/Pt capacitor-like system

Oxygen vacancy effect on the electronic state of Pt/NiO/Pt capacitor-like system is theoretically investigated by density functional theory (DFT) based first-principles calculations. The potential energy profile for electrons at the interface between Pt and NiO is found to play a major role on the transport properties alternations where conduction path begin to construct. Oxygen vacancies effect is summarized in the induction of a spatially localized spin-polarized state near the Fermi level of the surrounding Ni ions. Also, electron transport through O vacancy filaments (conduction paths) is via s-orbital sub-bands. We have found that the absence or presence of a vacancy near the interface at the edges of the vacancy filament causes a conductance jump from ~0 to 1e2/h respectively which corresponds to clearly observable switching.