Synthesis of high-purity (CaxLa1.00−x)(Ba1.75−xLa0.25+x)Cu3Oz tetragonal superconductor by an aqueous solution technique using citric acid

The Effect of Varying Ca-Content on the Structure of High-T_c Superconductor (Ca_xLa_1-x)(Ba_1.75-xLa_0.25+x)Cu₃O_7-δ (x = 0.5, 0.6, and 0.8) Studied by Neutron Powder Diffraction

“…In (Ca x La 1-x )(Ba 1.75-x La 0.25+x )Cu 3 O 7-(CLBLCO), which is one of the modifications of the Y-123 superconductor [1], the Y-site is occupied by calcium and lanthanum atoms, and the Ba-site is doped with lanthanum [2][3][4]. By changing the calcium and lanthanum content by varying x (0.0 x 1.0), it has been shown that T c of CLBLCO first increases close to 80 K, then slowly decreases and finally, at x = 1, settles back to the x = 0 value: 40 K [3,5]. In order to study the correlation between T c and the structural changes induced by doping, we have performed neutron powder diffraction (NPD) experiments on powders of CLBLCO prepared by an amorphous citrate method [5].…”

“…By changing the calcium and lanthanum content by varying x (0.0 x 1.0), it has been shown that T c of CLBLCO first increases close to 80 K, then slowly decreases and finally, at x = 1, settles back to the x = 0 value: 40 K [3,5]. In order to study the correlation between T c and the structural changes induced by doping, we have performed neutron powder diffraction (NPD) experiments on powders of CLBLCO prepared by an amorphous citrate method [5]. Nominal compositions for the studied samples were (Ca 0.5 La 0.5 )(Ba 1.25 La 0.75 )Cu 3 O 7-, (Ca 0.6 La 0.4 )(Ba 1.15 La 0.85 )Cu 3 O 7-and (Ca 0.8 La 0.2 )(Ba 0.95 La 1.05 )Cu 3 O 7-.…”