Chemical control of hole-doped superconductivity and magnetism in Gd2-xCexRuSr2Cu2O10-d
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Date
2003Author
McLaughlin, A C
Attfield, J. Paul
Asaf, U
Felner, I
Metadata
Abstract
Three Gd2-xCexRuSr2Cu2O10-d samples (x=0.5, as prepared and after high pressure oxygenation and x
=0.7) have been investigated by synchrotron powder x-ray diffraction and magnetization measurements.
Precise coordinates and site occupancies for the oxygen atoms have been refined from the x-ray experiments.
Estimates of the hole doping of the copper oxide planes based on the bond lengths, via the bond valence sum
method, are found to be inaccurate. However, doping estimates based on the refined oxygen contents are in
good agreement with the variation of superconductivity, and show that chemical doping, rather Cu/Ru band
overlap, is the doping mechanism. The magnetic ordering temperatures of the Ru moments are not a simple
function of the doping concentration, but depend upon both the Gd/Ce ratio and the oxygen content.