Structural Magnetic and Superconducting Properties of the Ba1-xEuxCuO3-y Compounds

Ba 1- x Eu x CuO 3- y compounds, (0 ≤ x ≤ 1), were prepared by a solid-state reaction. Samples with x between 0.3 and 0.5 were the single-phase type with an orthorhombic structure like Ba 2 Y 1 Cu 3 O 7 . The difference between a 0 and b 0 was maximum at around x =0.33. The intensity of the (001) reflection, which shows a three-layer repeat sequence and oxygen vacancy ordering, also has a maximum at the same Eu content. The composition and temperature dependences of the magnetic susceptibility indicated that the magnetic moment was associated with Eu 3+ . The maximum T c was obtained for a sample with x =0.30; the T c onset was about 100 K. T c was dependent on the Eu content and the oxygen vacancy ordering.