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arXiv · 0906.3519

Interface reconstruction in V-oxide heterostructures determined by x-ray absorption spectroscopy

H. Wadati·D. G. Hawthorn·J. Geck·T. Z. Regier·R. I. R. Blyth·T. Higuchi·Y. Hotta·Y. Hikita·H. Y. Hwang·G. A. Sawatzky
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Abstract

We present an x-ray absorption study of the dependence of the V oxidation state on the thickness of LaVO$_3$ (LVO) and capping LaAlO$_3$ (LAO) layers in the multilayer structure of LVO sandwiched between LAO. We found that the change of the valence of V as a function of LAO layer thickness can be qualitatively explained by a transition between electronically reconstructed interfaces and a chemical reconstruction. The change as a function of LVO layer thickness is complicated by the presence of a considerable amount of V$^{4+}$ in the bulk of the thicker LVO layers.

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H. Wadati, D. G. Hawthorn, J. Geck, T. Z. Regier, R. I. R. Blyth, T. Higuchi, Y. Hotta, Y. Hikita, H. Y. Hwang, G. A. Sawatzky. 2009-06-18. Interface reconstruction in V-oxide heterostructures determined by x-ray absorption spectroscopy. https://doi.org/10.1063/1.3177328

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