Irreversibility fields and critical current densities in strongly pinned YBa_2Cu_3O_(7-x) films with BaSnO_3 nanorods: The influence of segmented BaSnO_3 nanorods

摘要

We report irreversibility fields B_(irr) and critical current densities J_c in YBa_2Cu_3O_(7-x) thin films containing segmented BaSnO_3 nanorods. B_(irr) and J_c are systematically changed by selection of nanorod length and its spacing, and the variations are explained by the "harmonic oscillator" approach based on the Bose glass state. Analysis of pinning energies and J_c indicates that segmented nanorods behave as single columnar pin for B‖c, in contrast, as nanoparticle pins for B‖ab. The present results may help to further investigate anisotropy tuning of pinning structures.