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Electronic structures of Zn$_{1-x}$Co$_x$O using photoemission and x-ray absorption spectroscopy

S. C. Wi·J. -S. Kang·J. H. Kim·S. -B. Cho·B. J. Kim·S. Yoon·B. J. Suh·S. W. Han·K. H. Kim·K. J. Kim·B. S. Kim·H. J. Song·H. J. Shin·J. H. Shim·B. I. Min
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Abstract

Electronic structures of Zn$_{1-x}$Co$_x$O have been investigated using photoemission spectroscopy (PES) and x-ray absorption spectroscopy (XAS). The Co 3d states are found to lie near the top of the O $2p$ valence band, with a peak around $\sim 3$ eV binding energy. The Co $2p$ XAS spectrum provides evidence that the Co ions in Zn$_{1-x}$Co$_{x}$O are in the divalent Co$^{2+}$ ($d^7$) states under the tetrahedral symmetry. Our finding indicates that the properly substituted Co ions for Zn sites will not produce the diluted ferromagnetic semiconductor property.

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S. C. Wi, J. -S. Kang, J. H. Kim, S. -B. Cho, B. J. Kim, S. Yoon, B. J. Suh, S. W. Han, K. H. Kim, K. J. Kim, B. S. Kim, H. J. Song, H. J. Shin, J. H. Shim, B. I. Min. 2003-07-22. Electronic structures of Zn$_{1-x}$Co$_x$O using photoemission and x-ray absorption spectroscopy. https://doi.org/10.1063/1.1756197

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