Figure 3: Structure of the positively poled surface.

(a) An ABF image of the positively poled surface. The contrast is inverted and coloured for clarity. The arrow indicates the polarization is upward in this domain. Scale bar, 0.5 nm. (b) The vector map of the displacement between the Pb and ZrO/TiO columns overlaid with the ABF image. Scale bar, 0.5 nm. (c) The vector map of the displacement between the cation and anion columns. Scale bar, 0.5 nm. (d) Mean of the lattice parameter c near the surface. Seven data points were averaged to plot Pb lattice and six data points were averaged to plot ZrO/TiO lattice. The error bar is the s.d. (e) Mean of the z-component displacement between the Pb and ZrO/TiO columns. Seven data points were averaged to plot Pb displacement and six data points were averaged to plot ZrO/TiO displacement. The error bar is the s.d. (f) The magnitude map of the displacement between the cation and anion columns. (g) The long and short bond length of Pb–O along the z-direction. Seven data points were averaged to plot Pb–O bond length. The error bar is the s.d. The pink band highlights the shorter Pb–O length, which directly represents the magnitude of polarization in PZT. The grey band highlights the longer Pb–O length. No distinguishable difference is observed between the surface and subsurface. The dashed line 159 pm is calculated from the structure model in ref. 23.