Melt-textured growth and characterisation of a (Nd/Y)Ba2Cu3O7−δ composite superconductor with very high critical current density

Fabrication of large grain YBCO by seeded peritectic solidification

“…[26][27][28] The form of the magnetic moment hysteresis curves was similar for specimens B and C, which exhibited maximum J c 's of ϳ9000-10,000 A cm 22 at 1 T. II.…”

Flux pinning by Ba-site magnetic rare-earth ions in (rare-earth)1+uBa2−uCu3Ox compounds

“…The experimental fact that the magnetic rare-earth ions on Ba sites are the best flux pinners and pair breakers 18,23,24 ͑such as Ba-site Nd͒, 2,17,18 is very important, and implies that the magnetic scattering of Ba-site rare-earth ions is what matters: recall that the trivalent rare-earth ions replace Ba ϩ2 , and that a charge rebalancing or ''hole filling'' accompanies this replacement. All rare-earth ions are chemically and mechanically almost the same, having a Xe-like outer shell of radius ϳ1 Å ͑ranging from 0.85 Å for Lu ϩ3 to 1.14 Å for La ϩ3 ), and an inner 4 f shell of radius roughly ϳ0.4 Å, with a slight shrinkage of the outer shell radius as the rare earth becomes heavier: the famous ''lanthanide contraction.''…”

The homogeneity of levitation force in single domain YBCO bulk

“…Top-seeded melt texturing growth (TSMTG) [1,2] is one of the most important and effective ways to fabricate high quality YBCO bulk superconductors with a high levitation force at 77 K. The high levitation force of well textured YBCO bulks has attracted many scientists to work on its applications, such as magnetic bearings [3,4], flywheels [5] and levitated transportation systems [6]. For a TSMTG single-domain YBCO bulk superconductor, it is known that the levitation force is dependent on many parameters, such as the critical current density and grain radius, grain orientation, thickness of the sample and the cooling temperature [7].…”