Mapping octahedral tilts and polarization across a domain wall in BiFeO3 from Z-contrast STEM image atomic column shape analysis

Journal Article · Fri Jan 01 00:00:00 EST 2010 · ACS Nano

DOI:https://doi.org/10.1021/nn1011539· OSTI ID:992096

Borisevich, Albina Y ^[1]; Ovchinnikov, Oleg S ^[1]; Chang, Hye Jung ^[1]; Oxley, Mark P ^[1]; Yu, P ^[2]; Seidel, J ^[2]; Eliseev, E. A. ^[3]; Morozovska, A. N. ^[3]; Ramesh, R. ^[2]; Pennycook, Stephen J ^[1]; Kalinin, Sergei V ^[1]

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1. ORNL
2. University of California, Berkeley
3. National Academy of Science of Ukraine, Kiev, Ukraine

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 BiFeO3. 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.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 992096
• Journal Information: ACS Nano, Vol. 4, Issue 10; ISSN 1936-0851
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BISMUTH OXIDES
IRON OXIDES
ORDER PARAMETERS
POLARIZATION
TRANSMISSION ELECTRON MICROSCOPY
SCANNING ELECTRON MICROSCOPY
DOMAIN STRUCTURE
ORIENTATION