Angular-dependent vortex pinning mechanisms in YBa_(2)Cu_(3)O_(7) coated conductors and thin films

摘要

We compare the angular-dependent critical current density (J_(c)) in YBa_(2)Cu_(3)O_(7) films deposited on MgO templates grown by ion-beam-assisted deposition (IBAD), and on single-crystal substrates. We identify three angular regimes in which pinning is dominated by different types of correlated and uncorrelated defects. Those regimes are present in all cases, but their extension and characteristics are sample dependent, reflecting differences in texture and defect density. The more defective nature of the films on IBAD turns into an advantage as it results in higher J_(c), demonstrating that the performance of the films on single crystals is not an upper limit for the IBAD coated conductors.