Changes in electronic structure of the Bi-O and Cu-O planes due to the simultaneous doping of Pb at the Bi site and Y at the Ca site in the Bi-2212 system have been studied using core-level photoemission. The rare-earth doping at the Ca site causes an increase in the valence state of Bi and a decrease in average Cu valence. Incorporation of Pb into the system results in a retarded rate of increase of Bi valence. Pb, which seems to exist in two valence states in this system, may also be involved in a redox-type electron exchange mechanism with Bi and Cu. The results of Bi 4f, Pb 4f and Cu 2p core-level spectra of Pb-doped and Pb-free compounds are discussed.
XPS Studies on the Superconductor-Insulator Transition in Bi2-xPbxSr2Ca1-yYyCu2O8+d System / B. R., Sekhar; Saini, Naurang Lal; P. SRIVASTAVA, K. B. GARG. - In: JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS. - ISSN 0022-3697. - STAMPA. - 55:(1994), pp. 49-58. [10.1016/0022-3697(94)90183-X]
XPS Studies on the Superconductor-Insulator Transition in Bi2-xPbxSr2Ca1-yYyCu2O8+d System
SAINI, Naurang Lal;
1994
Abstract
Changes in electronic structure of the Bi-O and Cu-O planes due to the simultaneous doping of Pb at the Bi site and Y at the Ca site in the Bi-2212 system have been studied using core-level photoemission. The rare-earth doping at the Ca site causes an increase in the valence state of Bi and a decrease in average Cu valence. Incorporation of Pb into the system results in a retarded rate of increase of Bi valence. Pb, which seems to exist in two valence states in this system, may also be involved in a redox-type electron exchange mechanism with Bi and Cu. The results of Bi 4f, Pb 4f and Cu 2p core-level spectra of Pb-doped and Pb-free compounds are discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
