Study of the Electronic Structure of Various RE-Doped Oxypnictide Superconductors Using X-Ray Absorption Spectroscopy

Autor: Saurabh Dalela, Parvez Ahmad Alvi, D Neena, K. B. Garg
Rok vydání: 2014
Předmět:
Zdroj: Journal of Superconductivity and Novel Magnetism. 27:1431-1434
ISSN: 1557-1947
1557-1939
DOI: 10.1007/s10948-014-2496-1
Popis: The X-ray absorption spectroscopy (XAS) measurements on Fe L2,3-edge and O K-edge obtained at ELLETRA synchrotron Trieste, Italy are presented in this manuscript to study the electronic structure of REFeO1−x F x As (RE=Rare Earth elements; La, Ce, Sm) oxypnictide superconductors. The Fe L2,3- and O K-edge XAS for all the samples were found to be similar with varying intensity of the peaks. The results suggest that T c increases with doping of the rare earth elements as we go from a large periodic number to small; it is due to the size effect of rare earth ions with decrement in lattice spacing. Gaussians are fit to estimate the contribution of various spectral components in XAS spectra, and their relative spectral weight is calculated to correlate the density of states with T c’s of various RE doped oxypnictides.
Databáze: OpenAIRE