Garnet composite films with Au particles fabricated by repetitive formation for enhancement of Faraday effect

Abstract

To prepare garnet (Bi : YIG) composite films with Au particles, we used a repetitive formation method to increase the number density of particles. On increasing the number of repetitions, the diameter distribution of the particles changed. After five repetitions using 5 nm Au films, the diameter distribution separated into two size groups. Shift of wavelength-excited localized surface plasmon resonance is discussed relative to the diameter distribution. In the composite films, enhancement of Faraday rotation associated with surface plasmons was observed. With six repetitions, a maximum enhanced rotation of −1.2 • was obtained, which is 20 times larger than that of a single Bi : YIG film. The figures of merit for the composite films are discussed. The thickness of a Bi : YIG composite film working for enhanced Faraday rotation was examined using an ion milling method.

Magnetoplasmonics: Combining Magnetic and Plasmonic Functionalities

“…In fact, the main reason for the observed MO activity enhancement is the reduction of the refl ectivity, even though the MO component is also incremented, due to the enhancement of the EM fi eld inside the MO active layer. [119][120][121][122][123][124] For example, Figure 9. However, a simpler structural scenario may be faced if the MO component itself is dielectric in nature.…”

“…Later, other groups studied similar systems observing an increase of the Faraday rotation in the spectral region of the LSP resonance. [119][120][121][122][123][124] For example, Figure 9. Transmission spectra of Au nanoparticles embedded in bismuth-substituted yttrium iron garnet (Bi:YIG).…”

Faraday rotation in a disordered medium

“…These theories show only qualitative agreement with the experimental data of Refs. [15][16][17][18]. Many of the questions that have been raised during the experiments are still waiting for answers.…”

Influence of the Plasmonic Nanodisk Positions Inside a Magnetic Medium on the Faraday Effect Enhancement

“…To add magnetic functionality and, at the same time, keep optical losses at a moderate level, one could introduce magnetic dielectric materials surrounding noble metal particles. Considering this option, one of the most optimal configurations for magnetoplasmonic nanoantennas is represented by noble metal nanoparticles conjugated to a bulk magnetic insulator such as Bi‐substituted iron garnet . For this functional material, it has been demonstrated that LSPRs can enhance the magneto‐optical Faraday effect by about 20 times.…”

“…Considering this option, one of the most optimal configurations for magnetoplasmonic nanoantennas is represented by noble metal nanoparticles conjugated to a bulk magnetic insulator such as Bi-substituted iron garnet. [4,5,[19][20][21][22] For this functional material, it has been demonstrated that LSPRs can enhance the magneto-optical Faraday effect by about 20 times. In this article, we investigate theoretically and experimentally the influence of the immersion of gold nanodisks inside the magnetic dielectric film on the LSPR-mediated resonance of Faraday rotation.…”