Critical current control in YBa₂Cu₃O _7-δ films using artificial pinning centers

High-temperature superconductors can carry high non dissipative currents at low temperatures as long as quantized vortices are pinned. However, the currents in a magnetic field at liquid nitrogen temperature (77 K) are not sufficiently high for practical use due to the weak pinning. For the improvement of nondissipative currents in YBa₂Cu₃O _7-δ films, linear defects that extended to the c-axis of the film were introduced using a novel nanostructure technology. We observed a marked enhancement of the nondissipative currents even at 77 K and high fields when the fields were applied close to the c-axis. This is a clear demonstration of enhanced pinning using artificially incorporated pinning centers.