Critical current density and magnetic phase diagrams of BaFe1.29Ru0.71As2 single crystals

The critical current density has been measured on single crystals of Ru-substituted BaFe2As2 superconductor at several temperatures and in fields up to 16 T. The magnetization versus field isotherms reveal the occurrence of a clear second magnetization peak (SMP), also known as the fish-tail effect, for both H parallel and perpendicular to the c-axis of the crystal. The in-field resistance and magnetization data are used to draw a vortex phase diagram. The nature of the vortices has been determined from the scaling behaviour of the pinning force density extracted from the JC–H isotherms. (paper)