Hard X-ray Cu $2p$ Core-Level Photoemission of High-$T_c$ Cuprate Superconductors

M. Taguchi; M. Matsunami; A. Chainani; K. Horiba; Y. Takata; K. Yamamoto; R. Eguchi; M. Yabashi; K. Tamasaku; Y. Nishino; T. Nishio; H. Uwe; T. Mochiku; K. Hirata; J. Hori; K. Ishii; F. Nakamura; T. Suzuki; S. Shin; T. Ishikawa

arXiv · cond-mat/0612676

Hard X-ray Cu $2p$ Core-Level Photoemission of High-$T_c$ Cuprate Superconductors

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Abstract

We have performed a detailed study of Cu $2p$ core-level spectra in single layer La$_{2-x}$Sr$_{x}$CuO$_{4}$, La doped Bi$_2$Sr$_{1.6}$La$_{0.4}$CuO$_{6+δ}$ (Bi2201) and bilayer Bi$_2$Sr$_{2}$CaCu$_{2}$O$_{8+δ}$ (Bi2212) high-temperature superconductors by using hard x-ray photoemission (HX-PES). We identify the Cu$^{2+}$ derived (i) the Zhang-Rice singlet (ZRS) feature, (ii) the $d^{n+1}\underline{L}$ (ligand screened) feature, (iii) the $d^{n}$ satellite feature, as well as the hole-doping derived high binding energy feature in the main peak. In Bi-based cuprates, intensities of the $d^{n}$ satellite features seem to be strongly enhanced compared to La$_{2-x}$Sr$_{x}$CuO$_{4}$. From x-ray photon energy dependent measurements, it is shown that the increased intensity in the satellite region is associated with Bi $4s$ core-level spectral intensity. The corrected $d^{n}$ satellite intensity is independent of the doping content or number of Cu-O layers. Our results suggest a correlation of the relative intensity of ZRS feature and hole-doping induced high binding energy spectral changes in the main peak with superconductivity.

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M. Taguchi, M. Matsunami, A. Chainani, K. Horiba, Y. Takata, K. Yamamoto, R. Eguchi, M. Yabashi, K. Tamasaku, Y. Nishino, T. Nishio, H. Uwe, T. Mochiku, K. Hirata, J. Hori, K. Ishii, F. Nakamura, T. Suzuki, S. Shin, T. Ishikawa. 2006-12-28. Hard X-ray Cu $2p$ Core-Level Photoemission of High-$T_c$ Cuprate Superconductors. https://arxiv.org/abs/cond-mat/0612676

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