On the evolution of superconductivity in La1.5−xBa1.5−xCa2xCu3O7−δ(0.0⩽x⩽1.0)

Rietveld analysis and superconductivity of compounds

“…As a result, the hole concentration of La-336 was concentrated in the nonsuperconducting ODCu1-O layers with p ch = 0.647 [1], and the p sh = 0.074 was too small to show superconductivity Is figure 4 a universal relation for the tetragonal triple-perovskite La-Ca-Ba-Cu-O compounds containing 50 mol% Cu ions? The results of Goldschmidt et al [11], McCarron et al [18], Chao et al [19] and Gunasekaran et al [20] as well as our data are plotted in figure 5. In the calculation of OF, it was assumed that OF Ca/Y = x, if the Ca substitution was 0.50 or less and OF Ca/Y = 0.50 for x > 0.50.…”

Effect of disorder on the electrical and superconducting properties in Ln1.2Ba1.2Ca0.6Cu3O7+δ (Ln = La, Nd, Sm) and La1.2−xNdxBa1.2Ca0.6Cu3O7+δ

“…Copper-based oxides generated enormous interest after the discovery of superconductivity in Ln 2−x Ba x CuO 4 by Bednorz and Müller [1] followed by the discovery of the 123-type superconductors (LnBa 2 Cu 3 O 7−δ ) [2]. There is a less explored family of superconductors, derived from the 123 structure, represented as 1113 (LnBaCaCu 3 O 7−δ ) [3][4][5][6][7][8][9]. The La-1113 compound shows superconductivity in the range of 67-78 K [7][8][9][10][11].…”

“…There is a less explored family of superconductors, derived from the 123 structure, represented as 1113 (LnBaCaCu 3 O 7−δ ) [3][4][5][6][7][8][9]. The La-1113 compound shows superconductivity in the range of 67-78 K [7][8][9][10][11]. Unlike the 123 compounds, the 1113 compounds are stable only with lighter rare earths [10,12].…”

Structural properties of CaLaBaCu3O7-delta single crystals grown by self-flux method

“…This compound is a triple perovskite structure compound, (a= 3.87Åand c = 11.71Å, space group P4/mmm) and isostructural with the tetragonal YBa 2 Cu 3 O 7−δ . [4] In spite of their similarity, contrasting with the YBCO, the boundary between the superconducting and non superconducting phases of CaLaBaCu 3 O 7−δ , is defined only by oxygen content, without the complexity of the self-doping effects and the tetragonal-orthorhombic transition of crystalline structure, proper of the YBa 2 Cu 3 O 7−δ . [5] Since the CaLaBaCu 3 O 7−δ structure remains always tetragonal, independently of the oxygen content, the phase is congruent and the system does not present twins formation.…”