Microstructure and superconductivity in a new superconductor series: (Tl,Pb)1Sr2Can−1CunO2n+3−δ

The synthesis procedure and superconducting properties of the first two members of the new series of superconductors of a general formula: (Tl, Pb)1 Sr2 Can−1 Cun O2n+3−δ , are reported. The detailed atomic level microstructure of the compounds have been determined and computer simulated with structural models. Tc increases with n, the number of Cu-O2 layers per unit cell, as in the single Tl-layer Tl-Ba-Ca-Cu-O compounds, but the new materials have higher Tc ’s for the same value of n.