Variation of c-axis correlation on vortex pinning by ab-plane non-superconducting layers in YBa2Cu3O7 films

Abstract

Articles you may be interested inStrongly enhanced vortex pinning from 4 to 77 K in magnetic fields up to 31 T in 15 mol.% Zr-added (Gd, Y)-Ba-Cu-O superconducting tapes APL Mat. 2, 046111 (2014); 10.1063/1.4872060Dimpling in critical current density vs. magnetic field angle in YBa2Cu3O7 films irradiated with 3-MeV gold ionsIn YBa 2 Cu 3 O 7 (YBCO) þ BaSnO 3 (BSO)/PrBa 2 Cu 3 O 7 (PrBCO) multilayer films, behavior of vortices pinned by BSO nanorods was evaluated to discuss influence of ab-plane nonsuperconducting layers on c-axis correlated vortex pinning. Critical current density (J c ) and activation energy for thermally activated flux flow in magnetic field parallel to the c-axis were reduced by the PrBCO layers and a c-axis peak in an angular dependence of J c became small, as YBCO þ BSO layer thickness decreased or PrBCO layer thickness increased. Irreversibility temperature and trapping angle were not changed by the PrBCO layers for thick YBCO þ BSO layers and thin PrBCO layers. This indicates that the ab-plane non-superconducting layers accelerated the vortex motion along the ab-plane without changing the vortex structure. Thin YBCO þ BSO layers or thick PrBCO layers resulted in much more drastic degradation of the c-axis correlated vortex pinning due to two dimensional vortex nature or partially prevailed vortex structure, which decreased not only J c and activation energy, but also irreversibility temperature and trapping angle. Thus, the c-axis correlation of vortex pinning is varied by addition of the ab-plane non-superconducting layers. V C 2013 AIP Publishing LLC. [http://dx.

Fabrication and critical current density analysis of YBa2Cu3O7+(BaSnO3)′/YBa2Cu3O7+(BaSnO3)″ multilayer films

“…This suggests that similar results to those in the YBCO +BSO′/YBCO+BSO″ MLs are expected even for MLs containing other nanorod materials. Since we have been studying J c in YBCO films containing BSO, such as YBCO+BSO/ YBCO+PrBCO MLs [21], we can compare the present results with the previous ones without taking into account the difference in nanorod material. Therefore, BSO was selected as nanorod material in the present MLs.…”

“…Vortex pinning as well as T c , Josephson junction, and superconducting coupling can be tuned in MLs by introducing non-superconducting phases. Critical current density ( J c ) has been improved by Y 2 BaCuO 5 nanoparticles in YBCO/Y 2 BaCuO 5 quasi-MLs [16]; systematic variation of the glass-liquid transition temperature was confirmed in YBCO+BZO/YBCO MLs where nanorod length and distribution were controlled [17,18]; and J c -θ curves have been controlled in YBCO/BZO MLs [19,20]; Dimensional crossover and variation of vortex structure occurred in YBCO +BSO/PrBa 2 Cu 3 O 7 (PrBCO) MLs, resulting in J c degradation [21]. Since well-defined pinning centers were realized in MLs, characteristic vortex behavior that had not been observed in single layer films (SLs) was demonstrated.…”

“…In the YBCO+BSO/PrBCO [21], J c decreased very rapidly, and became 0 at PrBCO layer fraction of ∼0.2 due to non-superconductivity in PrBCO. Such rapid J c decrease was not observed in the present YBCO+BSO′/YBCO+BSO″ MLs since the present MLs consisted only of superconducting layers.…”

Combined effect of nanorod and stacking fault for improving nanorod interface in YBa2Cu3O7−δ nanocomposite films

“…The preferential vortex flow also occurs along the perpendicular planar defects. This has been observed in the YBCO + BSO/PrBCO multilayers, where J c has decreased with increasing a PrBCO layer thickness and with decreasing a PrBCO layer spacing [35].…”

Hybrid artificial pinning centers of elongated-nanorods and segmented-nanorods in YBa2Cu3O7films

“…Short, splayed, and segmented-nanorods varied the anisotropy of vortex pinning [14][15][16][17]. The hybrid APCs of BaSnO 3 (BSO) nanorods and Y 2 O 3 nanoparticles improved the J c -θ characteristics [18,19], but the hybrid APCs of BSO nanorods and PrBa 2 Cu 3 O 7 nanolayers degraded J c in the magnetic field parallel to the c-axis [20]. The hybrid APCs of nanorods and nanoparticles are one of the most effective structures in obtaining high J c values and isotropic J c simultaneously [18,19].…”