Using single-phase samples of the (Bi, Pb)2Sr2Ca2Cu3O10+δ [(Bi, Pb)-2223] high-Tc superconductor and utilizing two complementary analysis techniques, i.e., coulometric redox titration and x-ray-absorption near-edge structure spectroscopy at both O K and Cu L edges, the individual charges of the (Bi, Pb)2O2+δ charge reservoir and the superconductive block that contains the three CuO2 planes are consistently determined. Lead is found to enter the (Bi, Pb)-2223 phase with a valence close to III on average. As the oxygen content concomitantly decreases, the average CuO2-plane hole concentration decreases upon substituting bismuth in the pristine Bi-2223 phase with lead.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 5 Aug 2003|
|MoE publication type||A1 Journal article-refereed|