title: Imaging local polarization in ferroelectric thin films by coherent x-ray Bragg projection ptychography.
abstract: We used x-ray Bragg projection ptychography (BPP) to map spatial variations of ferroelectric polarization in thin film PbTiO3, which exhibited a striped nanoscale domain pattern on a high-miscut (001) SrTiO3 substrate. By converting the reconstructed BPP phase image to picometer-scale ionic displacements in the polar unit cell, a quantitative polarization map was made that was consistent with other characterization. The spatial resolution of 5.7 nm demonstrated here establishes BPP as an important tool for nanoscale ferroelectric domain imaging, especially in complex environments accessible with hard x rays.
authors.affiliation: Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA. shrus@anl.gov
authors.forename: S O
authors.initials: SO
authors.lastname: Hruszkewycz
authors.forename: M J
authors.initials: MJ
authors.lastname: Highland
authors.forename: M V
authors.initials: MV
authors.lastname: Holt
authors.forename: Dongjin
authors.initials: D
authors.lastname: Kim
authors.forename: C M
authors.initials: CM
authors.lastname: Folkman
authors.forename: Carol
authors.initials: C
authors.lastname: Thompson
authors.forename: A
authors.initials: A
authors.lastname: Tripathi
authors.forename: G B
authors.initials: GB
authors.lastname: Stephenson
authors.forename: Seungbum
authors.initials: S
authors.lastname: Hong
authors.forename: P H
authors.initials: PH
authors.lastname: Fuoss