We present the composite [Y1-xCax]SrBaCu2.80(PO4)0.20Oy (0.10 ≤ x ≤ 0.40) prepared at normal temperature and pressure conditions. X-ray diffraction patterns show that samples containing Ca crystallize in a 123 tetragonal structure with small amounts of impurities. The Rietveld method was used to refine the lattice constants. Ac and dc susceptibility measurements using a SQUID show that the materials are superconductors independent of Ca content. In the normal region the measurements of χDC show a typical Curie-Weiss law behavior.
Gonzalez Gonzalez, J. C., Bustamante Dominguez, A., Landinez Tellez, D., & Albino Aguiar, J. (2000). Superconductivity and magnetism in the system [Y<inf>1-x</inf>Ca<inf>x</inf>]SrBaCu<inf>2.80</inf>(PO<inf>4</inf>)<inf>0.20</inf>O<inf>y</inf> with 0.10 ≤ x ≤ 0.40. Physica C: Superconductivity and its Applications. https://doi.org/10.1016/S0921-4534(00)00626-2