Hysteretic magnetic pinning and reversible resistance switching in High-Tc superconductor/ferromagnet multilayers

TL;DR

This paper investigates how magnetic history influences resistance switching in high-Tc superconductor/ferromagnet multilayers, revealing hysteretic effects driven by stray magnetic fields affecting vortex dynamics.

Contribution

It demonstrates the role of stray magnetic fields in causing resistance changes through vortex creation and pinning in superconductor/ferromagnet hybrids.

Findings

Resistance decreases or increases depending on magnetic history.

Stray magnetic fields induce vortices and antivortices.

Magnetostatic pinning affects vortex behavior.

Abstract

We study a high-TC superconducting (YBa2Cu3O7-d) / ferromagnetic (Co/Pt multilayer) hybrid which exhibits resistance switching driven by the magnetic history: depending on the direction of the external field, a pronounced decrease or increase of the mixed-state resistance is observed as magnetization reversal occurs within the Co/Pt multilayer. We demonstrate that stray magnetic fields cause these effects via i) creation of vortices/antivortices and ii) magnetostatic pinning of vortices that are induced by the external field.