Fig. 2: Compressive force-induced rearrangement of La³⁺ inhomogeneities.

a HAADF-STEM micrograph along [100]_p.c. of a region that has been exposed to 140 μN of compressive force. Superimposed on the HAADF-STEM image are the STEM intensities normalized to the maximum intensity of the A-site (labeled Bi³⁺/La³⁺) atomic columns plotted at their fitted coordinates. The blue and red arrows indicate the up- and down-shifts of the Bi³⁺/La³⁺ ions, respectively. b Averaged vertical line profile of (a). The green and dark blue dashed lines indicate the two distinct intensity levels of alternating La³⁺-rich and La³⁺-poor planes, respectively. c Topography micrograph demonstrating the surface reorganization of a region after exposure to a compressive force of 140 μN—indicated by a white dashed square—with respect to the pristine region. The line profile below corresponds to the dashed blue line in the micrograph. The purple- and light blue-shaded regions denote the pristine and stressed areas, respectively. d, e LPFM, and VPFM micrographs of the same region as depicted in (c). The antipolar region is marked with a dashed white square.