Crystal structure, superconductivity and magnetic properties of the superconducting ferromagnets Gd1.4−xDyxCe0.6Sr2RuCu2O10 (x=0–0.6)

Abstract The structural, electrical and magnetic properties of the superconducting ferromagnets, Gd 1.4− x Dy x Ce 0.6 Sr 2 RuCu 2 O 10 ( x =0–0.6) are systematically investigated as a function of Dy doping and temperature. These compounds are characterized by high temperature superconductivity ( T c ranging from 20 to 40 K depending upon the Dy content) co-existing with weak ferromagnetism with two magnetic transitions ( T M2 ranging from 95 to 106 K and T M1 around 120 K). Doping with Dy gives no significant structural changes except for a minor change in the c / a ratio. However the superconducting transition temperature is significantly suppressed and magnetic ordering temperature enhanced on Dy doping. These effects are described and discussed.