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We presented here the fluctuation induced excess conductivity in Bi 1.7 Pb 0.3 Sr 2 Ca 2-x Y x Cu 3 Oy superconductors with various x values (0.00 x 0.50). The logarithmic plots of excess conductivity (∆ σ) and reduced temperature (ε) reveal three different values of the order parameter dimensional exponents against a decrease of temperature corresponding to two different values of crossover temperatures. In the critical field region, the order parameter exponents are two dimensional (2D) as x increases up to 0.20, but it is changed to three dimensional (3D) with further increase of x up to 0.50. While, the order parameter exponents are not systematic with Y in both normal and mean field regions, and they are fluctuated between zero dimensional/short wave (0D/SW), qusi-2D, qusi-1D and 3D. On the other hand, the coherence lengths, inter-plane spacing, interlayer coupling, GL parameter and anisotropy are calculated and their values are generally increased by increasing x up to 0.50, whereas GL parameter, Ginsburg number, critical magnetic fields and critical current density are decreased. The possible reasons for the above findings are also mentioned.

We presented here the fluctuation induced excess conductivity in Bi 1.7 Pb 0.3 Sr 2 Ca 2-x Y x Cu 3 Oy superconductors with various x values (0.00 x 0.50). The logarithmic plots of excess conductivity (∆ σ) and reduced temperature (ε) reveal three different values of the order parameter dimensional exponents against a decrease of temperature corresponding to two different values of crossover temperatures. In the critical field region, the order parameter exponents are two dimensional (2D) as x increases up to 0.20, but it is changed to three dimensional (3D) with further increase of x up to 0.50. While, the order parameter exponents are not systematic with Y in both normal and mean field regions, and they are fluctuated between zero dimensional/short wave (0D/SW), qusi-2D, qusi-1D and 3D. On the other hand, the coherence lengths, inter-plane spacing, interlayer coupling, GL parameter and anisotropy are calculated and their values are generally increased by increasing x up to 0.50, whereas GL parameter, Ginsburg number, critical magnetic fields and critical current density are decreased. The possible reasons for the above findings are also mentioned.

The normal and superconducting properties of Bi1.7Pb0.30Sr2Ca2−xLaxCu2Oy (Bi, Pb):2223 system with various x values (0.00 ≤ x ≤ 0.30) have been reported. It is found that the replacement of Ca2+ by La3+ up to 0.30 does not influence the phase purity of the pure system, while the orthorhombic distortion, excess oxygen, effective Cu valance and hole carriers/Cu ions are clearly affected. Further, the doping distance and crystal geometry factor are decreased, but the distance between neighboring Cu-atoms and density of excess doping are increased. Furthermore, the DTA diagrams show strong endothermic peaks Tm at 844.1, 848, 850.1 and 857.4 °C for pure and La samples, respectively. The mass loss determined by TGA displayed a sharp mass loss started at about 800 °C and extended to 1000 °C for all samples. Although the critical temperatures Tc of the samples are decreased by La insertion …

The normal and superconducting properties of Bi1.7Pb0.30Sr2Ca2−xLaxCu2Oy (Bi, Pb):2223 system with various x values (0.00 ≤ x ≤ 0.30) have been reported. It is found that the replacement of Ca2+ by La3+ up to 0.30 does not influence the phase purity of the pure system, while the orthorhombic distortion, excess oxygen, effective Cu valance and hole carriers/Cu ions are clearly affected. Further, the doping distance and crystal geometry factor are decreased, but the distance between neighboring Cu-atoms and density of excess doping are increased. Furthermore, the DTA diagrams show strong endothermic peaks Tm at 844.1, 848, 850.1 and 857.4 °C for pure and La samples, respectively. The mass loss determined by TGA displayed a sharp mass loss started at about 800 °C and extended to 1000 °C for all samples. Although the critical temperatures Tc of the samples are decreased by La insertion …

The normal and superconducting properties of Bi1.7Pb0.30Sr2Ca2−xLaxCu2Oy (Bi, Pb):2223 system with various x values (0.00 ≤ x ≤ 0.30) have been reported. It is found that the replacement of Ca2+ by La3+ up to 0.30 does not influence the phase purity of the pure system, while the orthorhombic distortion, excess oxygen, effective Cu valance and hole carriers/Cu ions are clearly affected. Further, the doping distance and crystal geometry factor are decreased, but the distance between neighboring Cu-atoms and density of excess doping are increased. Furthermore, the DTA diagrams show strong endothermic peaks Tm at 844.1, 848, 850.1 and 857.4 °C for pure and La samples, respectively. The mass loss determined by TGA displayed a sharp mass loss started at about 800 °C and extended to 1000 °C for all samples. Although the critical temperatures Tc of the samples are decreased by La insertion …

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