High-field paramagnetic Meissner effect up to 14 T in melt-textured YBa2Cu3O7-delta

• Main Authors: Teixeira Dias, Fábio, Vieira, Valdemar das Neves, Wolff-Fabris, Frederik, Kampert, Erik, Paiva Gouvêa, Cristol de, Campos, A.P.C, Archanjo, B.S, Schaf, Jacob, Obradors Berenguer, Xavier, Puig, T, Roa Rovira, Joan Josep, Sahoo, B.K
• Format: Publication
• Language: English
• Published: 01-06-2016
• Subjects: ac magnetic-susceptibility; enhanced critical currents; Física; high-temperature superconductors; josephson-junction arrays; Magnetic flux compression; Magnetic relaxation; Magnetització; Magnetization; microstructure; Paramagnetic Meissner effect; single-crystals; system; time-dependence; Vortex pinning; yba2cu3o7-y2bacuo5 composites; Àrees temàtiques de la UPC
• ISSN: 0921-4534
• DOI: 10.1016/j.physc.2016.03.013

We have performed magnetization experiments in a melt-textured YBa2Cu3O7-delta(Y123) sample with Y2BaCuO5 (Y211) inclusions, under magnetic fields up to 14 T applied parallel or perpendicular to the ab plane. Magnetic anisotropy and paramagnetic moments were observed in both FC (field-cooling) and FCW (field-cooled warming) procedures and these features correspond to the so-called High-Field Paramagnetic Meissner Effect (HFPME). The HFPME effect increases monotonically as the magnetic field rises and a strong paramagnetic relaxation, toward increasing paramagnetic moment was additionally observed as a function of time. Microscopy analysis revealed a complex and correlated microstructure of the Y211 particles. These correlated defects are well known to cause strong flux pinning. Our results suggest a scenario of strong flux compression within weak or non-superconducting regions of the samples, developed as a consequence of the Meissner effect and assisted by strong flux pinning by the Y211 particles. This scenario is observed up to 14 T and clearly persists beyond. (C) 2016 Elsevier B.V. All rights reserved.
Peer Reviewed