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Orbital Reconstruction in a Self-assembled Oxygen Vacancy Nanostructure.

ABSTRACT: We demonstrate the microscopic role of oxygen vacancies spatially confined within nanometer inter-spacing (about 1?nm) in BiFeO3, using resonant soft X-ray scattering techniques and soft X-ray spectroscopy measurements. Such vacancy confinements and total number of vacancy are controlled by substitution of Ca(2+) for Bi(3+) cation. We found that by increasing the substitution, the in-plane orbital bands of Fe(3+) cations are reconstructed without any redox reaction. It leads to a reduction of the hopping between Fe atoms, forming a localized valence band, in particular Fe 3d-electronic structure, around the Fermi level. This band localization causes to decrease the conductivity of the doped BiFeO3 system.

SUBMITTER: Jang H

PROVIDER: S-EPMC4515763 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Orbital Reconstruction in a Self-assembled Oxygen Vacancy Nanostructure.

Jang H H Kerr G G Lim J S JS Yang C-H CH Kao C-C CC Lee J-S JS

Scientific reports 20150727

We demonstrate the microscopic role of oxygen vacancies spatially confined within nanometer inter-spacing (about 1 nm) in BiFeO3, using resonant soft X-ray scattering techniques and soft X-ray spectroscopy measurements. Such vacancy confinements and total number of vacancy are controlled by substitution of Ca(2+) for Bi(3+) cation. We found that by increasing the substitution, the in-plane orbital bands of Fe(3+) cations are reconstructed without any redox reaction. It leads to a reduction of th ...[more]

PMID: 26213281

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