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Title: Polarization pinning at antiphase boundaries in multiferroic YbFeO 3
Abstract The switching characteristics of ferroelectrics and multiferroics are influenced by the interaction of topological defects with domain walls. We report on the pinning of polarization due to antiphase boundaries in thin films of the multiferroic hexagonal YbFeO3. We have directly resolved the atomic structure of a sharp antiphase boundary (APB) in YbFeO3thin films using a combination of aberration-corrected scanning transmission electron microscopy (STEM) and total energy calculations based on density-functional theory (DFT). We find the presence of a layer of FeO6octahedra at the APB that bridges the adjacent domains. STEM imaging shows a reversal in the direction of polarization on moving across the APB, which DFT calculations confirm is structural in nature as the polarization reversal reduces the distortion of the FeO6octahedral layer at the APB. Such APBs in hexagonal perovskites are expected to serve as domain-wall pinning sites and hinder ferroelectric switching of the domains.  more » « less
Award ID(s):
2122070 2145797
PAR ID:
10587909
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
arxiv
Date Published:
Journal Name:
Chinese Physics B
Volume:
33
Issue:
11
ISSN:
1674-1056
Page Range / eLocation ID:
118502
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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