Origin Of Resistance Switching And Regulation Of The Resistance Stability By The Interface State Density On The Pt/Nb:Srtio3 Interface

The surface defect and carrier concentrations of Nb-doped SrTiO3 (NSTO) single crystals play an important role in its resistance switching (RS) properties. Herein, the RS of both 0.05 and 0.7 wt% Nb-doped NSTO single crystals are studied. The hole defects on NSTO, which are characterized by electron paramagnetic resonance, increase with the enhanced Nb-doping level. The hole defects with positive charges directly affect the RS characters of the Pt/NSTO junction by electron trapping/detrapping. The stability and discrimination of the resistance states are correlated with the interface state density and carrier concentration, which is controlled by the Nb-doping level. The fundamental physical processes are proposed according to the experimental results.