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Updated: Jun 8, 2026
Picometer-Precision Atomic Position Tracking through Electron Microscopy
Published on: July 3, 2021
Mapping octahedral tilts and polarization across a domain wall in BiFeO3 from Z-contrast scanning transmission
Albinay Borisevich1, Oleg S Ovchinnikov, Hye Jung Chang
1Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States. albinab@ornl.gov
Abstract:
Oxygen octahedral tilts underpin the functionality of a large number of perovskite-based materials and heterostructures with competing order parameters. We show how a precise analysis of atomic column shapes in Z-contrast scanning transmission electron microscopy images can reveal polarization and octahedral tilt behavior across uncharged and charged domain walls in BiFeO(3). This method is capable of visualizing octahedral tilts to much higher thicknesses than phase contrast imaging. We find that the octahedral tilt transition across a charged domain wall is atomically abrupt, while the associated polarization profile is diffuse (1.5-2 nm). Ginzburg-Landau theory then allows the relative contributions of polarization and the structural order parameters to the wall energy to be determined.
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