CHARACTERIZATION OF THE EUROPIUM SUBSTITUTED SUPERCONDUCTING BI2SR2CACU2O8+Y PHASE

Effects ot europium substitution on the stoichiometry, structure and superconductivity ot the Bi2Sr2CaCu2O8+y phase have been investigated. Partial replacement of calcium by europium promotes the single-phase formation and leads to an uptake of extra oxygen into the structure. Oxygen content in the Bi2Sr2Ca1-xEuxCu2O8+y materials was determined by the thermogravimetric hydrogen reduction method. In an attempt to locate the intercalated oxygen atoms x-ray, neutron and electron diffraction techniques were used. In addition, the samples were characterized by AC magnetic susceptibility measurements as well as by Eu-151 Mossbauer spectroscopy. The applicability of these methods and the results obtained thereby are discussed.