Peculiarities of the Faraday effect in gold-nanodisk/iron-garnet heterostructures

TL;DR

This study investigates how gold nanodisks embedded in magnetic media affect the Faraday effect, revealing optimal configurations for maximum Faraday rotation enhancement through experimental and theoretical analysis.

Contribution

It provides new insights into the placement of gold nanoparticles within magnetic media to optimize Faraday rotation, combining experimental and numerical approaches.

Findings

Maximum Faraday rotation occurs when nanoparticles are inside the magnetic film.

Optimal nanoparticle placement is 6 nm beneath the magnetic surface.

Magnetic properties of the medium significantly influence the Faraday effect.

Abstract

In this paper, matters considering the immersion of gold nanoparticles inside a magnetic medium are investigated experimentally and theoretically. Three samples with periodic arrays of Au cylinders where studied: particles on a surface of the magnetic dielectric film, inside the magnetic film and directly under the magnetic film. The largest LSPR mediated Faraday rotation resonance enhancement takes place for the case of the nanoparticles submerged inside the magnetic film. Optimal place for nanoparticles is under the magnetic medium surface at 6 nm deep in the considered configurations. It is shown that the most influence on the Faraday rotation enhancement is produced by the magnetic properties of the medium between the nanoantennas. The experimental results are in good agreement with the numerical analysis.