Probing Magnetic Configurations in Co/Cu Multilayered Nanowires

TL;DR

This study uses first-order reversal curve methods to identify magnetic configurations in buried Co nanodiscs within multilayered nanowires, revealing how aspect ratio influences magnetic states and magnetoresistance behaviors.

Contribution

It introduces a novel approach to probe magnetic states in buried nanostructures and demonstrates control of magnetic configurations via nanodisc aspect ratio in Co/Cu nanowires.

Findings

Single domain behavior in thin nanodiscs

Vortex states in thicker nanodiscs

Superposition of magnetoresistance effects

Abstract

Magnetic configurations in heterostructures are often difficult to probe when the magnetic entities are buried inside. In this study we have captured magnetic and magnetoresistance "fingerprints" of Co nanodiscs embedded in Co/Cu multilayered nanowires using a first-order reversal curve method. In 200nm diameter nanowires, the magnetic configurations can be tuned by adjusting the Co nanodisc aspect ratio. Nanowires with the thinnest Co nanodiscs exhibit single domain behavior, while those with thicker Co reverse via vortex states. A superposition of giant and anisotropic magnetoresistance is observed, which corresponds to the different magnetic configurations of the Co nanodiscs.