A periodic array of nano-scale twin boundaries was formed within melt-processed YBa2Cu3O7–δ with RuO2 additions. The arrangement of the regular twin boundaries along the c axis irreversibility improved the line and critical current density. A characteristic kink was found at 2.75T on the c-axis irreversibility line; indicative of correlated disorder. The field tilt-angle below which pinning by the twin boundary was effective was found to be about 40°. An attempt was made to reconcile these data with the predictions of the Bose-glass model for correlated disorder.

Engineering Periodic Arrays of Nanoscale Twin Boundaries in Bulk YBa2Cu3O7–δ with RuO2 Additions. L.Shlyk, G.Krabbes, G.Fuchs, C.Mickel, B.Rellinghaus, K.Nenkov: Applied Physics Letters , 2006, 88[6], 062509 (3pp)