Abstract A macroscopic transport mechanism for superconductivity is lacking. In this work, we performed a complete impeditivity spectrum analysis of a 122-family electron-doped pnictide, i.e. BaFe 2− x Ni x As 2 ( x = 0.065, 0.085, 0.1, 0.12, 0.15, 0.2, and 0.25). Below the critical temperature, the complex impeditivity exhibited in-plane anisotropy, with the AC resistivity as its real part and AC inductive reactivity as its imaginary part. In terms of electron duality, we emphasize the wave nature rather than the particle nature. The vortex waves of paired electrons propagated along the c axis of the single crystals to pass through series-connected nanoslabs in the ab -plane. In each nano-slab, the quantum nanodomains (QNs) of the magnetic flux in the Abrikosov sublattice were surrounded by a conducting region. The nano-slab was identified using the geometric-phase coefficient of a positive integer. Parallel nanodomains were the same in the nano-slabs, and all of them were characterized by the nano-slab coefficient when the conducting region was zero. The complex impeditivity plot revealed conducting heterogeneity between superconducting QNs and the conducting region. When the QN contained a magnetic flux quantum, the superconducting current was amplified, where the quantum number was dependent not only on the crystal axis but also on the dopant. When we predicted the ultimate superconductor with zero impeditivity, the other nanodomains exhibited a magnetic flux with left-hand spiral symmetry, which could be characterized by the geometric-phase coefficient of the negative integer. The co-doping of electrons and holes in an ultimate superconductor may be a solution for practical power transmission at room temperature.
原文链接
分享
引用
