We report magnetic field dependence of the transport critical current and dc magnetic susceptibility measurements on YBa2Cu3O7−x superconductors formed by melt-solid reactions at 950 °C between Ba-Cu-O (or Tb-Ba-Cu-O) and solid nonstoichiometric Y-Ba-Cu-oxide. Four-probe dc critical current measurements at 77, 64, and 4.2 K show strong depression of the critical current density with increasing magnetic field in agreement with a model of weakly linked superconducting regions. Diamagnetic shielding and Meissner flux expulsion measurements in the temperature range 10–300 K show about one third volume fraction of perfect superconductivity. Both shielding and flux expulsion were observed to be approximately temperature independent below 60 K indicating strong coupling between the grains throughout the entire volume below this temperature.
Transport Critical Current and Magnetization Measurements of Melt-Processed YBa2Cu3O7-XJournal of Applied Physics
Publisher's StatementCopyright 1988 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Journal of Applied Physics 64 (1988): 5050-5055 and may be found at http://link.aip.org/link/doi/10.1063/1.342459.
Citation InformationHermann, A. H. , Z. Z. Sheng, W. Kiehl, D. Marsh, A. Elali, Paul D. Hambourger, C. Almasan, J. Estrada, and T. Datta. "Transport Critical Current and Magnetization Measurements of Melt-Processed YBa2Cu3O7-X." Journal of Applied Physics 64 (1988): 5050-5055.