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Title: Atomic scale crystal field mapping of polar vortices in oxide superlattices
Abstract Polar vortices in oxide superlattices exhibit complex polarization topologies. Using a combination of electron energy loss near-edge structure analysis, crystal field multiplet theory, and first-principles calculations, we probe the electronic structure within such polar vortices in [(PbTiO 3 ) 16 /(SrTiO 3 ) 16 ] superlattices at the atomic scale. The peaks in Ti $$L$$ L -edge spectra shift systematically depending on the position of the Ti 4+ cations within the vortices i.e., the direction and magnitude of the local dipole. First-principles computation of the local projected density of states on the Ti $$3d$$ 3 d orbitals, together with the simulated crystal field multiplet spectra derived from first principles are in good agreement with the experiments.
Authors:
; ; ; ; ; ; ; ; ;
Award ID(s):
1708615
Publication Date:
NSF-PAR ID:
10331638
Journal Name:
Nature Communications
Volume:
12
Issue:
1
ISSN:
2041-1723
Sponsoring Org:
National Science Foundation
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