Title :
High pressure oxygenation in melt textured NdBa/sub 2/Cu/sub 3/O/sub 7/: identification of pinning mechanisms
Author :
Puiog, T. ; Obradors, X. ; Martinez, B. ; Sandiumenge, F. ; Gomis, V. ; Alonso, J.A.
Author_Institution :
Inst. de Ciencia de Mater., Univ. Autonoma de Barcelona, Spain
fDate :
6/1/1999 12:00:00 AM
Abstract :
A competing effect inducing both an enhancement of interface pinning and aging of the critical currents has been established in NdBa/sub 2/Cu/sub 3/O/sub 7-/spl delta///Nd/sub 4/Ba/sub 2/Cu/sub 2/O/sub 10/ (Nd123/422) melt-textured ceramic composites upon high oxygen pressure annealing. It is suggested that Nd123/422 interfaces are enriched in antisite defects, which are properly oxygenated only upon high PO/sub 2/ annealing. Additional evidence for the enhanced oxygenation is gained from the observation of a consequent decrease of the field induced anomaly at intermediate fields.
Keywords :
annealing; antisite defects; barium compounds; ceramics; composite superconductors; critical current density (superconductivity); flux pinning; high-temperature superconductors; melt texturing; neodymium compounds; stoichiometry; Nd/sub 4/Ba/sub 2/Cu/sub 2/O/sub 10/; Nd123/422 interfaces; Nd123/422) melt-textured ceramic composites; NdBa/sub 2/Cu/sub 3/O/sub 7-/spl delta//; NdBa/sub 2/Cu/sub 3/O/sub 7/; aging; annealing; antisite defects; competing effect; critical currents; enhanced oxygenation; field induced anomaly; high oxygen pressure annealing; high pressure oxygenation; interface pinning; intermediate fields; melt textured NdBa/sub 2/Cu/sub 3/O/sub 7/; pinning mechanisms; Aging; Annealing; Ceramics; Composite materials; Critical current; Critical current density; Fabrication; Magnetic materials; Solids; Superconducting transition temperature;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
