Investigation of some physical properties of silver diffusion-dopedYBa2Cu3O7−x superconductors

Abstract

Silver diffusion in superconductingYBa2Cu3O7−x (YBCO) has been studied over the temperature range500–800 °C by x-ray diffraction measurements. The diffusion coefficient of Ag in YBCOwas determined from the observed increase (0.12%) in the lattice parameterc ascompared with the undoped sample. It was shown that the diffusion coefficient of Ag in the temperaturerange 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 transitiontemperature and the critical current density were increased from 90 to 92.5 K and from 60 to98 A cm−2 respectively in comparison with those of undoped YBCO. The possible reasons for the observed increasesin Tc and Jc due to Ag diffusion were discussed.