1 research outputs found
Atomic-Level Response of the Domain Walls in Bismuth Ferrite in a Subcoercive-Field Regime
The atomic-level response of zigzag ferroelectric domain
walls
(DWs) was investigated with in situ bias scanning transmission electron
microscopy (STEM) in a subcoercive-field regime. Atomic-level movement
of a single DW was observed. Unexpectedly, the change in the position
of the DW, determined from the atomic displacement, did not follow
the position of the strain field when the electric field was applied.
This can be explained as low mobility defect segregation at the initial
DW position, such as ordered clusters of oxygen vacancies. Further,
the triangular apex of the zigzag wall is pinned, but it changes its
shape and becomes asymmetric under electrical stimuli. This phenomenon
is accompanied by strain and bound charge redistribution. We report
on unique atomic-scale phenomena at the DW level and show that in
situ STEM studies with atomic resolution are very relevant as they
complement, and sometimes challenge, the knowledge gained from lower
resolution studies