Superconducting Properties in Y_1-xBa_xCuO_3-y and Y(Ba_1-xSr_x)²Cu₃O_7-y

Abstract

The concentration dependence of the transition temperature Tc has been studied in high-Tc Y 1-x Ba x CuO 3-y and Y(Ba 1-x Sr x ) 2 Cu 3 O 7-y systems. In Y 1-x Ba x CuO 3-y , Tc exhibits a maximum at x=0.67 compound with a stoichiometry YBa 2 Cu 3 O 7-y . In Y(Ba 1-x Sr x ) 2 Cu 3 O 7-y , Tc decrease monotonically with an increase of Sr content.