Fig. 3. Extracted information from a 4D-data set of the reduced Pr_0.8Sr_0.2NiO_2+x film.

Reconstructed atomic-column-resolved a ADF, and b electric field images. c The electric-field map extracted from the region marked with a black dashed box in b. d The line profile extracted from the region marked with a black dashed line in c indicates the changes in the magnitude of the electric field around B (B: Ni, and Ga) atoms. e A PrNiO₃ supercell created from the ABF image of a reduced sample with polar distortions at the upper surface. f Simulated electric field map. g The corresponding line profile of the electric field map marked with a white dashed line in f.