Vortex Confinement in Superconducting/Ferromagnet Hybrid Structures

ORAL

Abstract

Magnetically coupled superconductor-ferromagnet hybrids offer advanced routes for nanoscale control of superconductivity. Scanning tunneling microscopy (STM) and scanning magnetic force microscopy (MFM) coupled to magneto-transport measurements reveal rich vortex phase diagram. The magnetic stripe domain of the ferromagnet induces periodic local magnetic induction in the superconductor, creating a series of pinning and anti-pinning channels for vortices observed with low temperature STM and MFM. Such laterally confined Abrikosov vortices form chains. We also found general equilibrium condition for which vortex-antivortex pairs are spontaneously formed during zero-field cooling. In the non-equilibrium state the strong magnetic pinning of the vortex lattice results in avalanches of antivortices when changing the polarity of the applied magnetic field.

Authors

  • M. Iavarone

    • Physics Department, Temple University, Philadelphia, PA 19122, USA

  • A. Scarfato

    • Physics Department, University of Salerno, Fisciano 84084, Italy

  • F. Bobba

    • Physics Department, University of Salerno, Fisciano 84084, Italy

  • M. Longobardi

    • Physics Department, University of Salerno, Fisciano 84084, Italy

  • F. Giubileo

    • CNR-SPIN Laboratory, Salerno, Italy

  • G. Karapetrov

    • Materials Science Division, Argonne National Laboratory, Argonne, IL 60439, USA

  • V. Novosad

    • Materials Science Division, Argonne National Laboratory, Argonne, IL 60439, USA

  • V.G. Yefremenko

    • Materials Science Division, Argonne National Laboratory, Argonne, IL 60439, USA

  • A. Cucolo

    • Physics Department, University of Salerno, Fisciano 84084, Italy