Effects of Europium-Barium Nonstoichiometry in EBCO123 Systems on Transition and Magnetization Properties

We studied the effects of Eu-Ba nonstoichiometry in two series of $Eu_{1+x}Ba_{2-x}Cu_3O_{7-δ}$ and $Eu_{1-x}Ba_{2+x}Cu_3O_{7-δ}$ samples on transition, structural, and magnetic properties. The samples with the nominal composition of 0≤x≤0.07 were synthesized by the solid-state reaction method from $Eu_2O_3,$ $BaCO_3,$ and CuO precursors and sintered at 1050°C for 72 h in flowing oxygen. All the samples show the values of critical temperature $T_c$, volume density ρ, and maximum volume magnetization $M_\text{max}$ higher than 90 K, 6.3 g $cm^{-3}$ and $10^4 Am^{-1}$, respectively, except for x = 0.07 samples. The Eu-Ba nonstoichiometry in the two series shows different effects on transport, magnetization hystereses, and intergrain properties of the samples

Study of light nonstoichiometry in Eu-Ba-Cu-O systems

We studied effects of light Eu-Ba nonstoichiometry in Eu-Ba-Cu-O superconducting compounds on their transition, structural, and magnetic properties. Two series of Eu1+xBa2-x Cu3O7+delta and Eu1-x Ba2+xCu3O7+delta samples with x = 0, 0.01, 0.02, 0.04, 0.05, 0.07 and 0.1 were synthesized by the solid-state reaction method from Eu2O3, BaCO3 and CuO precursors and sintered at 1050 degrees C for 72 h in flowing oxygen. Structural, transition, and magnetic properties were investigated by means of X-ray diffraction, resistance, mutual inductance, magnetization and optical measurement methods. The Eu-Ba nonstoichiometry in the two series results in different effects on transport, magnetization, grain, intergrain and microstructure properties of the samples in relation to the substitution level of x. All the samples show the values of critical temperature T-c, volume density rho, and maximum volume magnetization M-max higher than 91 K, 6.4 g cm(-3) and 10(4) Am-1, respectively