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

Yasushi Sato , M. Valkeapää , Valery Petrykin, Minoru Osada , S.-g. Eriksson , Masato Kakihana , Håkan Rundlöf