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X-ray Photoemission Study of the Infinite-Layer Cuprate Superconductor Sr0.9La0.1CuO2

R. P. Vasquez·C. U. Jung·J. Y. Kim·Min-Seok Park·Heon-Jung Kim·Sung-Ik Lee
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Abstract

The electron-doped infinite-layer superconductor Sr0.9La0.1CuO2 is studied with x-ray photoemission spectroscopy (XPS). A nonaqueous chemical etchant is shown to effectively remove contaminants and to yield surfaces from which signals intrinsic to the superconductor dominate. These data are compared to measurements from hole-doped La1.85Sr0.15CuO4, from undoped La2CuO4, and from electron-doped Nd1.85Ce0.15CuO4-d. The Cu 2p core level is consistent with a lower value of the O 2p to Cu 3d charge transfer energy D than in hole-doped cuprates. A clear Fermi edge is observed in the valence band region.

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R. P. Vasquez, C. U. Jung, J. Y. Kim, Min-Seok Park, Heon-Jung Kim, Sung-Ik Lee. 2001-07-10. X-ray Photoemission Study of the Infinite-Layer Cuprate Superconductor Sr0.9La0.1CuO2. https://doi.org/10.1088/0953-8984%2F13%2F35%2F305

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