Importance of Magnetoresistivity Properties and Decrement of the Flux Pinning Energy in YBa2Cu3O7−x Bulk Superconductors Doped with Gd Nanoparticles

• Published in: Journal of superconductivity and novel magnetism Vol. 27; no. 3; pp. 681 - 686
• Main Authors: Dogruer, M., Terzioglu, C., Gorur, O., Yildirim, G.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.03.2014
• Subjects: Activation energy; Characterization and Evaluation of Materials; Condensed Matter Physics; COPPER OXIDE; Flux pinning; MAGNETIC FIELD; Magnetic fields; Magnetic Materials; Magnetism; Magnetoresistivity; Nanoparticles; Original Paper; PARTICLES; Physics; Physics and Astronomy; PINNING; Strongly Correlated Systems; SUPERCONDUCTIVITY; SUPERCONDUCTORS; Transition temperature; Upper critical field; Irreversibility field; Flux pinning energy; Magnetotransport measurements
• ISSN: 1557-1939; 1557-1947
• DOI: 10.1007/s10948-013-2353-7

Magnetoresistivity performance of the polycrystalline YBa 2 Cu 3− x Gd x O 7− x (Y123) superconductors is discussed by the change of the flux pinning mechanism using magnetotransport measurements performed in the magnetic field range from 0 to 7 T. The critical transition temperatures, irreversibility fields ( μ 0 H irr ), upper critical fields ( μ 0 H c 2 ), penetration depths ( λ ) and coherence lengths ( ξ ) of the Y123 materials are deduced from the magnetoresistivity curves. Further, activation (flux pinning) energies belonging to the samples are determined from thermally activated flux creep (TAFC) model. The results obtained display that the flux pinning energies reduce with enhancing the applied magnetic field. This may be attributed to the fact that Gd nanoparticles inserted in the Y123 superconducting core lead to exhibit much weaker flux pinning, lesser crystallinity and connectivity between grains as compared to the pure sample due to the presence of stronger pair-breaking mechanism.