Enhanced Faraday Rotation via Resonant Tunnelling in Tri-Layers Containing Magneto-Optical Metals

TL;DR

This paper demonstrates that resonant tunnelling in tri-layer structures with magneto-optical metals significantly enhances Faraday rotation at optical frequencies, achieving higher transmittance than single-layer counterparts.

Contribution

It introduces a novel tri-layer design exploiting resonant tunnelling to boost Faraday rotation and transmittance in magneto-optical devices.

Findings

Resonant tunnelling causes resonance splitting that enhances Faraday rotation.

Tri-layer structures achieve ~10° Faraday rotation with higher transmittance.

Enhanced effects are maintained even with realistic material losses.

Abstract

We study resonant tunnelling effects that can occur in tri-layer structures featuring a dielectric layer sandwiched between two magneto-optical-metal layers. We show that the resonance splitting associated with these phenomena can be exploited to enhance Faraday rotation at optical frequencies. Our results indicate that, in the presence of realistic loss levels, a tri-layer structure of sub-wavelength thickness is capable of yielding sensible (~10{\deg}) Faraday rotation with transmittance levels that are an order of magnitude larger than those attainable with a standalone slab of magneto-optical metal of same thickness.