Abstract
X-ray photoemission spectra (XPS) and Raman measurements of Y1-xEuxBa2Cu3O7 and Eu1-xPrxBa2Cu3O7 are compared to those of Y1-xPrxBa2Cu3O7. It is shown that, with increasing x, the binding energies of the Ba core levels of Eu1-xPrxBa2Cu3O7 shift towards higher values as in Y1-xPrxBa2Cu3O7, while those of Y1-xEuxBa2Cu3O7 do not, despite similar changes in Ba-O interatomic distances in the latter two systems. Raman measurements of Y1-xPrxBa2Cu3O7 show a frequency increase of the Ba and apical-oxygen modes with increasing x, but a much smaller frequency increase in Y1-xEuxBa2Cu3O7. The XPS and Raman results reflect changes in the Ba-O hybridization and correlate with both the suppression of superconductivity in both Y1-xPrxBa2Cu3O7 and Eu1-xPrxBa2Cu3O7, and with the retention of superconductivity in Y1-xEuxBa2Cu3O7.
Original language | English |
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Pages (from-to) | 10544-10547 |
Number of pages | 4 |
Journal | Physical Review B |
Volume | 43 |
Issue number | 13 |
DOIs | |
State | Published - 1991 |