Superconducting properties of the Fe-substituted La2.5Y0.5CaBa3(Cu1-xFex)(7)O-z perovskite

The structural and superconducting properties of single-phase Fe-substitute d La2.5Y0.5CaBa3(Cu1-xFex)(7)O-z [LYCBCuFe] with 0 less than or equal to x less than or equal to 0.15 compounds having triple-perovskite structure are investigated using X-ray diffraction, resistivity, AC Susceptibility, oxyg en content and Mossbauer effect measurements. The observed reduction of T-c with increasing x in LYCBCuFe supports the view that magnetic pair breakin g by local moments contributes predominantly to the suppression of supercon ductivity by Fe. The observed Fe-dopant site occupancies and the Cu(2) plan e to the Cu(1) chain site ratio in the LYCBCuFe obtained from Mossbauer spe ctral analysis of x = 0.02 sample are quite different from those of the usu al Fe-doped YBa2Cu3Oz. (C) 1999 Elsevier Science B.V. All rights reserved.