Fig. 1: Structural and ferroelectric properties.
From: Sub-nanosecond memristor based on ferroelectric tunnel junction
a Left panel: HAADF-STEM image of the Ag/BTO/NSTO FTJ at the virgin state with the inset showing the Ti ion displacement in BTO. The orange and green spheres denote Ba and Ti ions, respectively. Right panel: Elemental profiles obtained from the EELS of Ba and Ti elements. b Mean value of the out-of-plane lattice spacing near the BTO/NSTO interface. The error bars indicate standard deviations. c, d HAADF-STEM images of the FTJs after poling the ferroelectricity upward and downward by −3 and +3 V voltage pulses with td = 100 ns. Insets show displacements of Ti ions. e, f Ag element distributions measured by the EDS mapping for FTJs after poling the ferroelectricity upward and downward. g PFM hysteresis loops in phase (orange) and amplitude (blue). h PFM phase and i PFM amplitude images recorded after writing an area of 3 × 3 μm2 with −6 V and then the central 1 × 1 μm2 with +6 V by a biased conductive tip.
