Fluctuation, Diamagnetic Transition, and FTIR Spectra of La Substituting Ca in (Bi, Pb): 2223 Superconductor
Research Abstract
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 …
Research Journal
Journal of Superconductivity and Novel Magnetism
Research Pages
11
Research Publisher
Springer US
Research Rank
1
Research Vol
6(10)
Research Website
https://link.springer.com/article/10.1007/s10948-020-05651-7
Research Year
2020