Superconductor/ferromagnet bilayers: Influence of magnetic domain structure on vortex dynamics

Abstract

We study the magnetically coupled superconductor-ferromagnet bilayers comprised of a ferromagnet with a rotatable periodic stripelike magnetic domain structure with alternating out-of-plane component of magnetization and a MoGe superconductor. We demonstrate a prominent difference in critical current density between cases when magnetic domain stripes are oriented parallel and perpendicular to the superconducting current. The bilayer exhibits pronounced commensurability features that are related to the matching periodicities of the Abrikosov vortex lattice and the magnetic stripe domains.