Details

Autor(en) / Beteiligte

• Nylén, H.
• Qvarford, M.
• Chiaia, G.
• Tjernberg, O.
• Söderholm, S.
• Zakharov, A.A.
• Leandersson, M.
• Nazin, V.G.
• Tsetlin, M.B.
• Lev, L.
• Andersen, J.N.
• Nyholm, R.
• Lindau, I.
• Karlsson, U.O.
• Mikheeva, M.N.
• Leonyuk, L.

Titel

O KVV Auger emission versus resonant photoemission at the O K edge of high- Tc superconductors

Ist Teil von

• Physica. C, Superconductivity, 1998, Vol.300 (3), p.161-170

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

1998

Link zum Volltext

Quelle

Elsevier Journal Backfiles on ScienceDirect (DFG Nationallizenzen)

Beschreibungen/Notizen

• Photoelectron spectroscopy results on single crystals of the superconductors Bi 2Sr 2CaCu 2O 8,Bi 2Sr 2CuO 6, Ba 0.6K 0.4BiO 3 and the semiconductor Ba 0.9K 0.1BiO 3 are reported for the photon energy region around the O K absorption threshold. The development of the O- KVV Auger structure has been carefully monitored as a function of photon energy. A non-monotonic behavior displaying a feature at a constant binding energy of about 14 eV was found for Bi 2Sr 2CaCu 2O 8 and Bi 2Sr 2CuO 6 in a narrow photon energy region of 1 eV at the main edge of the O K absorption spectrum around 530 eV. The corresponding enhancement, connected with the autoionization of O 2 p states, is absent in Ba 1− x K x BiO 3 in contrast to Bi 2Sr 2CaCu 2O 8 and Bi 2Sr 2CuO 6. The resonant enhancement is more pronounced for Bi 2Sr 2CuO 6 as compared to Bi 2Sr 2CaCu 2O 8, which can be explained by a lower charge carrier concentration in the former case, leading to a more localized nature of intermediate O 2 p states. The model parameters Cu d– d and O p– p Coulomb interactions and the charge transfer energy Δ are estimated from the experiments.