Remote hole-doping of Mott insulators on the nanometer scale

M. Takizawa; Y. Hotta; T. Susaki; Y. Ishida; H. Wadati; Y. Takata; K. Horiba; M. Matsunami; S. Shin; M. Yabashi; K. Tamasaku; N. Nishino; T. Ishikawa; A. Fujimori; H. Y. Hwang

arXiv · 0806.2191

Remote hole-doping of Mott insulators on the nanometer scale

M. Takizawa·Y. Hotta·T. Susaki·Y. Ishida·H. Wadati·Y. Takata·K. Horiba·M. Matsunami·S. Shin·M. Yabashi·K. Tamasaku·N. Nishino·T. Ishikawa·A. Fujimori·H. Y. Hwang

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Abstract

At interfaces between polar and nonpolar perovskite oxides, an unusual electron-doping has been previously observed, due to electronic reconstructions. We report on remote hole-doping at an interface composed of only polar layers, revealed by high-resolution hard x-ray core-level photoemission spectroscopy. In LaAlO3/LaVO3/LaAlO3 trilayers, the vanadium valence systematically evolves from the bulk value of V3+ to higher oxidation states with decreasing LaAlO3 cap layer thickness. These results provide a synthetic approach to hole-doping transition metal oxide heterointerfaces without invoking a polar discontinuity.

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M. Takizawa, Y. Hotta, T. Susaki, Y. Ishida, H. Wadati, Y. Takata, K. Horiba, M. Matsunami, S. Shin, M. Yabashi, K. Tamasaku, N. Nishino, T. Ishikawa, A. Fujimori, H. Y. Hwang. 2008-06-13. Remote hole-doping of Mott insulators on the nanometer scale. https://arxiv.org/abs/0806.2191

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