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DOE OSTI · 1798872

Electronic properties of single-layer CoO 2 /Au(111)

Abstract

Here we report direct measurements via angle-resolved photoemission spectroscopy (ARPES) of the electronic dispersion of single-layer (SL) CoO 2 . The Fermi contour consists of a large hole pocket centered at the $\overline{\Gamma}$ point. To interpret the ARPES results, we use density functional theory (DFT) in combination with the multi-orbital Gutzwiller Approximation (DFT+GA), basing our calculations on crystalline structure parameters derived from x-ray photoelectron diffraction and low-energy electron diffraction. Our calculations are in good agreement with the measured dispersion. We conclude that the material is a moderately correlated metal. We also discuss substrate effects, and the influence of hydroxylation on the CoO 2 SL electronic structure.

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BibTeXRIS

Holt, Ann U., Pakdel, Sahar, Rodríguez-Fernández, Jonathan, Zhang, Yu, Curcio, Davide, Sun, Zhaozong, Lacovig, Paolo, Yao, Yong-Xin, Lauritsen, Jeppe V., Lizzit, Silvano, Lanatà, Nicola, Hofmann, Philip, Bianchi, Marco, Sanders, Charlotte E.. 2021-06-11. Electronic properties of single-layer CoO 2 /Au(111). https://doi.org/10.1088/2053-1583%2Fac040f

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36 MATERIALS SCIENCE↗