Photoemission Electronic States of Thallium- and Bismuth-Based Superconductors

• Authors: R. Zalecki , A. Kołodziejczyk , J.W. König , G. Gritzner
• Languages of publication: EN

Abstracts

EN

X-ray photoemission spectra the core-levels as well as the X-ray photoemission spectra and ultraviolet photoemission spectra from the valence bands of the (Tl_{0.6}Pb_{0.5})(Sr_{0.9}Ba_{0.1}) Ca_{2}Cu_{3}O_{y} and (Bi_{1.75}Pb_{0.35})Sr_{1.9}Ca_{2.05}Cu_{3.05}O_{y} superconductors were measured and analyzed. Special attention was paid to the valence band X-ray photoemission spectra and ultraviolet photoemission spectra, the Cu 2p core-level X-ray photoemission spectra and the Cu L_{2,3}-M_{4,5}M_{4,5} and O K-L_{2,3}L_{2,3} Auger spectra. Both Cu 2p_{3/2} and Cu 2p_{1/2} core-level lines consisted of two spin-orbit split main lines accompanied with the two satellite lines. The charge transfer energy Δ from the oxygen ligand to the copper 3d^{9} states and the hopping integral t were estimated from the energy separation between the main line and the satellite line taking advantage of the local cluster model calculations and their extension to high-temperature superconductors. The Coulomb correlation on-site energy U_{dd} of two electrons in the same copper orbital and U_{pp} of two electrons in the oxygen orbital as well as the correlation energy U_{cd} of the 2p core hole - 3d electron interaction have been estimated from the Auger electron spectra and the valence band spectra. They are: U_{dd}=6.0±0.5eV, of U_{pp}≅ 10±1eV and of U_{cd}≅ 8.0±0.5eV nearly the same for both the Tl- and Bi-compounds. We conclude that these compounds are the charge transfer strongly-correlated metals.

Keywords

EN

74.72.-h; 79.60.-i

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2000
• Volume: 98
• Issue: 5
• Pages: 513-524

Dates

published

2000-11

Contributors

author

R. Zalecki

• University of Mining and Metallurgy, Faculty of Physics and Nuclear Technique Al. A. Mickiewicza 30, 30-059 Cracow, Poland

author

A. Kołodziejczyk

• University of Mining and Metallurgy, Faculty of Physics and Nuclear Technique Al. A. Mickiewicza 30, 30-059 Cracow, Poland

author

J.W. König

• Johannes Kepler Universität, Institut für Chemische Technologie Anorganischer Stoffe 4040 Linz, Austria

author

G. Gritzner

• Johannes Kepler Universität, Institut für Chemische Technologie Anorganischer Stoffe 4040 Linz, Austria