Anisotropy of the critical current density and intrinsic pinning behaviors of YBa₂Cu₃O_y coated conductors

The intrinsic pinning mechanism of YBa₂Cu₃O _y coated conductors was investigated in terms of the anisotropy of J_c. The dissipation in the intrinsic pinning is mainly due to the double-kink excitation of the pinned vortices in the intermediate temperature region between 70 and 40 K. In this temperature region, the n-value is as small as about 8-10. At low temperature below 20 K, however, n-values become large and J_c is independent of the magnetic field because of the reduction of the double-kink excitation of the vortices.