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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 [(PbTiO₃)₁₆/(SrTiO₃)₁₆] superlattices at the atomic scale. The peaks in Ti [Formula: see text]-edge spectra shift systematically depending on the position of the Ti⁴⁺ 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 [Formula: see text] orbitals, together with the simulated crystal field multiplet spectra derived from first principles are in good agreement with the experiments.

SUBMITTER: Susarla S

PROVIDER: S-EPMC8560910 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Atomic scale crystal field mapping of polar vortices in oxide superlattices.

Susarla Sandhya S García-Fernández Pablo P Ophus Colin C Das Sujit S Aguado-Puente Pablo P McCarter Margaret M Ercius Peter P Martin Lane W LW Ramesh Ramamoorthy R Junquera Javier J

Nature communications 20211101 1

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 [(PbTiO3)16/(SrTiO3)16] superlattices at the atomic scale. The peaks in Ti [Formula: see text]-edge spectra shift systematically depending on the position of the Ti4+< ...[more]

PMID: 34725320

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