Synthesis of RuSr 2(Ln 3/4Ce 1/4) 2Cu 2O 10 magneto-superconducting compounds with Ln=Ho, Y and Dy by high-pressure high-temperature technique

Abstract

The samples of composition RuSr 2(Ln 3/4Ce 1/4) 2Cu 2O 10 with Ln=Ho, Y and Dy, being synthesized by high-pressure high-temperature (6 GPa, 1200 °C) solid-state synthesis route do crystallize in space group I4/ mmm. These samples exhibit magnetic transitions at ∼150 K with significant branching of zero-field-cooled (zfc) and field-cooled (fc) magnetization and a sharp cusp in zfc at ∼100 K, followed by a possible superconducting transition at lower temperatures. All the compounds show typical ferromagnetic hysteresis loops in magnetic moment ( M) vs. field ( H) magnetization at 5 K. Near saturation of the moments at 5 K is achieved in above 5 T (Tesla) applied fields with a value of ∼0.80 μ B. At low temperatures (5 K) these compounds exhibit both superconductivity and ferromagnetism. To our knowledge these are first successfully synthesized Ru-1222 compounds with various lanthanides including Y, Dy, and Ho. The results are compared with widely reported Gd/Ru-1222 compound.