Superconductivity controlled by the magnetic state of ferromagnetic nanoparticles

TL;DR

This paper demonstrates how the magnetic state of ferromagnetic nanoparticles can control superconductivity in hybrid structures, revealing a strong dependence of critical current on magnetic configuration.

Contribution

It introduces a novel hybrid superconductor/ferromagnetic nanoparticle structure with controlled magnetic states affecting superconducting properties.

Findings

Critical current $I_c(H)$ depends strongly on the magnetic state of nanoparticles.

Fabrication of arrays of Co nanoparticles on Josephson junctions and Nb microbridge.

Magnetic configuration influences superconducting behavior in hybrid structures.

Abstract

Novel hybrid superconductor/ferromagnetic particles structures are presented. Arrays of Co submicron particles were fabricated on overlap, edge type Josephson junctions and on a narrow Nb microbridge by means of high-resolution e-beam lithography.We observed a strong dependence between the magnetic state of the particles and the field-dependent critical $I_c(H)$ of these structures.