B. M. Gong

YBa2Cu3O7-x Prepared by a Polymer-Metal-Complex Precursor Process: Morphology and Superconducting Transition Properties

Abstract By careful control of calcination conditions for the preparation of YBa 2 Cu 3 O 7− x by a polymer-metal-complex process, X-ray pure samples having uniformly sized grains can be prepared. The electrical transport properties of samples with grain sizes in the range 0.5–10 μm have been measured as a function of temperature, density and magnetic field.

Transport properties of Ag-YBa2Cu3O7−x fibers prepared by a polymer-metal-complex precursor process

Abstract We report studies of the properties of an Ag-YBa 2 Cu 3 O 7− x (Ag-123) fiber typical of those we have produced by a variation of the polymer-metal-complex (PMC) precursor technique of Chien et al. Detailed results for the temperature, current and magnetic field dependence of the DC electrical transport properties are presented for a fiber of diameter ≈ 15 μm which has a DC j c =1300 A/cm 2 at 77K (10 nV/cm criterion) and 15 500 A/cm 2 at 4.2 K (1 μV/cm criterion) in zero field. The results differ significantly from non-silver-added prepared by the same PMC process.

Transport properties of Ag-Y123 fibers prepared using the polymer-metal precursor technique

We report on the fabrication and superconducting transport properties of superconducting fibers with typical cross-sectional areas of 10 2 to 10 3 μm 2 made using the polymer-metal precursor (PMC) technique. These samples show superconducting properties similar to good quality bulk polycrystalline pellets, with J c (77K) ~ 10 3 A/cm 2 and J c (4K) ~ 10 4 A/cm 2 . Magnetic field measurements show that the fiber’s superconducting transport properties are dominated by weak links between grains, as in bulk polycrystalline materials.