Structure and superconducting properties of (Bi,Pb):2223 superconductor with 3D excess conductivity

The full pattern decomposition method by Le Bail was applied to a single phase orthorhombic (Bi,Pb):2223 superconductor with an accentuated three dimensional excess conductivity The space group Pmam, with the lattice parameters a = 5.2598, b = 5.5381, c = 37.174 Angstrom was found. The Fourier maps derived show that delocalization of the Sr atoms induces terracing of the Cu/Ca/Cu superconducting stacking of 0.3 Angstrom, close to the c-axis coherence length, yielding the three dimensional character of the conduction evidenced by the resistivity measurements.