Combinative energy and properties of Y1−xSrxBa2−xLaxCu3Oy system

Abstract The compensated systems of Y 1− x Sr x Ba 2− x La x Cu 3 O y were synthesized and characterized by DC magnetization measurements and X-ray diffraction. The structures of the samples were refined by Rietveld method. Although the carrier concentration in the samples is constant at different doping levels, the superconductivity evidently changes. The combinative energy in the system was calculated and it was discovered that the decrease of T c has close relationship with the increase of the combinative energy. It is suggested that the structural factor should be taken into account when considering the mechanism of high T c superconductivity.