Nucleation and Arrangement of Abrikosov Vortices in Hybrid Superconductor-Ferromagnetic Nanostructure

TL;DR

This paper explores how Abrikosov vortices nucleate and arrange themselves in hybrid superconductor-ferromagnetic nanostructures under inhomogeneous magnetic fields, revealing complex behaviors and pinning mechanisms.

Contribution

It introduces a detailed simulation study of vortex behavior in hybrid nanostructures, highlighting novel stationary configurations caused by inhomogeneous magnetic fields.

Findings

Unusual stationary vortex configurations identified.

Vortex structures undergo creep-like deformation.

Pinning mechanisms are influenced by geometric and magnetic inhomogeneities.

Abstract

This study investigates the nucleation, dynamics, and stationary configurations of Abrikosov vortices in hybrid superconductor-ferromagnetic nanostructures exposed to inhomogeneous magnetic fields generated by a ferromagnetic nanodot. Using time-dependent Ginzburg-Landau simulations and Maxwell's equations, we observe and provide an explanation for the evolution of curved vortex structures that undergo creep-like deformation while reaching a steady state. Spatial variations in the Lorentz force, along with the interaction between geometric constraints and vortex interactions, give rise to unusual stationary vortex configurations that gradually change with increasing field strength, a behavior not seen in homogeneous magnetic fields. These findings reveal complex pinning mechanisms, providing valuable insights for the optimization and further advancement of nanoscale superconducting systems.