Doping evolution of the oxygen K-edge x-ray absorption spectra of cuprate superconductors using a three-orbital Hubbard model

Ronny Thomale
Amer Physical Soc, 2013
Article

We study oxygen K-edge x-ray absorption spectroscopy (XAS) and investigate the validity of the Zhang-Rice singlet (ZRS) picture in overdoped cuprate superconductors. Using large-scale exact diagonalization of the three-orbital Hubbard model, we observe the effect of strong correlations manifesting in a dynamical spectral weight transfer from the upper Hubbard band to the ZRS band. The quantitative agreement between theory and experiment highlights an additional spectral weight reshuffling due to core-hole interaction. Our results confirm the important correlated nature of the cuprates and elucidate the changing orbital character of the low-energy quasiparticles, but also demonstrate the continued relevance of the ZRS even in the overdoped region.

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Ronny Thomale
Amer Physical Soc, 2013
Article

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https://infoscience.epfl.ch/record/189208?ln=fr

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