SUPERCONDUCTIVITY IN Ru-BASED CUPRATE Ru(Sr_1.5Ca_0.5)PbCu₂O₈ PREPARED BY SOL–GEL ROUTE

Abstract

Pb containing ruthenium-based superconducting cuprates Ru ( Sr 1.5 Ca 0.5) PbCu 2 O 8 ( Ru -1212 type) have been successfully synthesized through the sol–gel route. The optimum annealing temperature for the ruthenium-based cuprate superconductor was found to be 890°C. The crystal structure determined by X-ray powder diffraction method showed a single Ru -1212 type phase with tetragonal symmetry with lattice parameters a = b = 3.920 Å, and c = 11.76 Å. The Ru ( Sr 1.5 Ca 0.5) PbCu 2 O 8 material showed onset temperature, Tc -onset at 35 K and zero resistant temperature, Tc -zero at 20 K. Pb together with the partial substitution of Sr with Ca lowered the formation temperature of the Ru -1212 type phase.

SUPERCONDUCTING RuSr2(Gd2-xCex)Cu2O8-δ PREPARED BY SOL–GEL ROUTE

“…7 In previous reports, it was shown that the Ru(Sr 1.5 Ca 0.5 )PbCu 2 O 8 superconductors could be synthesized by the sol-gel route. 8 In this brief report, we describe the preparation of superconducting RuSr 2 (Gd 2−x Ce x )Cu 2 O 10−δ , with x = 0.5, 0.6, 0.7, using the sol-gel method. This route resulted in the formation of single-phase superconducting Ru-1222 for x = 0.6, in a one-step process.…”