Magneto-optical observation of the influence of an artificial periodic magnetic pattern on the pinning of a YBa2Cu3O7-δ thin film

Abstract

In a recent paper [1], it has been shown from transport measurements that artificial reversible pinning can be created by the application of a magnetic tape on the surface of a thin superconducting film. We study the influence of a periodic array of magnetic stripes, generated from a signal pre-recorded on a magnetic tape, on the pinning of vortices. With our high resolution magneto-optical technique [2], we visualize in two dimensions the penetration of the flux in a thin YBa2Cu3O7-δ film partially covered by such a magnetic tape. In particular, we investigate the evolution of flux entry in the superconducting strip under and next to the magnetic tape. We present results obtained for various temperatures and various applied fields.