Details

Autor(en) / Beteiligte

• TALLON, J. L
• POOKE, D. M
• BUCKLEY, R. G
• PRESLAND, M. R
• FLOWER, N. E
• GIBSON, S
• GILBERD, P. W

Titel

Enhanced flux pinning by combined atomic substitution and phase decomposition in cuprate superconductors

Ist Teil von

• Applied physics letters, 1991-09, Vol.59 (10), p.1239-1241

Ort / Verlag

Melville, NY: American Institute of Physics

Erscheinungsjahr

1991

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The use of combined atomic substitution and phase decomposition is shown to achieve substantial enhancement of flux pinning in Y–Ba-Cu–O ceramics. The substituent is chosen to provide a high density of nucleation sites for decomposition and at the same time enhancing Tc in the resulting composite superconductor. Bulk YBa2Cu4O8 (124) with 2.5% La substituted for Ba is decomposed by a short anneal beyond the stability boundary for YBa2Cu3O7 (123) at low oxygen pressure. The product, principally La-substituted 123 <m1;37p>with stacking faults and precipitates of CuO in the grain boundaries, exhibits a 17-fold enhancement in intragrain Jc at 77 K and 0.75 Tesla over unprocessed 123, rising to 50-fold at 85 K. Magnetization Jc exceeds 104 A/cm2 at 0.75 Tesla for temperatures up to 87 K, the highest so far observed for a superconductor.