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arXiv · 1508.02334

Orbital Reconstruction in a Self-assembled Oxygen Vacancy Nanostructure

H. Jang·G. Kerr·J. S. Lim·C. -H. Yang·C. -C. Kao·J. -S. Lee
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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 Ca2+ for Bi3+ cation. We found that by increasing the substitution, the in-plane orbital bands of Fe3+ 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.

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H. Jang, G. Kerr, J. S. Lim, C. -H. Yang, C. -C. Kao, J. -S. Lee. 2015-08-10. Orbital Reconstruction in a Self-assembled Oxygen Vacancy Nanostructure. https://doi.org/10.1038/srep12402

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