DISCONTINUITY LINES IN RECTANGULAR SUPERCONDUCTORS WITH INTRINSIC ANDEXTRINSIC ANISOTROPIES

Magneto-optical investigations of the flux distributions in the critic al state of a c-axis-oriented square YBa2Cu3O7-delta thin film with an extrinsic anisotropy induced by an in-plane magnetic field are presen ted. The dependence of the anisotropy ratio of the critical currents o n the orientation of the in-plane field with respect to the direction of current flow is determined. The results are compared with Aux distr ibutions in a rectangular DyBa2Cu3O7-delta single crystal with a micro structural anisotropy induced by the introduction of oblique linear de fects. For the intrinsic anisotropy the flux is found to penetrate par allel to the inclination direction of the pins even if the flux motion is then not parallel to the Lorentz force exerted by the shielding cu rrents. The angular distribution of the critical currents in general i s different from the elliptic distribution, which was found for the ex trinsic anisotropy.