Investigation of some physical properties of silver diffusion-doped YBa₂Cu₃O_7−xsuperconductors

Abstract

Silver diffusion in superconducting YBa2Cu3O7−x (YBCO) has been studied over the temperature range 500–800 °C by x-ray diffraction measurements. The diffusion coefficient of Ag in YBCO was determined from the observed increase (0.12%) in the lattice parameter c as compared with the undoped sample. It was shown that the diffusion coefficient of Ag in the temperature range 500–800 °C changed from 1 × 10−10 to 5 × 10−9 cm2 s−1 with an activation energy of about 1.06 eV. For the Ag-doped sample, the critical transition temperature and the critical current density were increased from 90 to 92.5 K and from 60 to 98 A cm−2 respectively in comparison with those of undoped YBCO. The possible reasons for the observed increases in Tc and Jc due to Ag diffusion were discussed.

Conductivity fluctuations of polycrystalline Ag-doped YBa2Cu3O7-δ superconductor

“…On the other hand, the lattice parameter c decrease from 11.695 (4)Å for pure sample to 11.683 (2)Å for GB, 11.680 (2)Å for GC and to 11.650 (3)Å for GD sample. The change of c lattice parameter with Ag addition suggests the presence of silver inside the grains [16]. The obtained lattice parameters are in agreement with published results [8][9][10].…”

High critical current density and improved flux pinning in bulk MgB2 synthesized by Ag addition

“…This may open wide spread applications of MgB 2 . In our recent study doping of La in MgB 2 has been found to increase critical current density due to LaB 6 In earlier studies Ag admixing has been reported to result in enhancement of critical current density in cuprate superconductors [23][24][25] . Recently studies on synthesis and superconducting characteristics of Ag admixed MgB 2 have been reported [26][27][28] .…”

Investigation of some physical properties of Gd added Bi-2223 superconductors

“…Extensive substitution and doping studies have been carried out on Bi-based high-T c superconductors in order to improve their microstructure, mechanical and superconducting properties and to explain the mechanism of superconductivity [7,[19][20][21][22]. In previous studies [18,23], we investigated the effect of Gd addition on the mechanical and superconducting properties of the samples that are used in the present study.…”