Switching and propagation of magneto-plasmon-polaritons in magnetic slot waveguides and cavities

TL;DR

This paper derives the dispersion relations for magneto-plasmon-polaritons in a metal-insulator-metal waveguide with a magneto-optically active dielectric, demonstrating magnetic control over light propagation and radiation emission.

Contribution

It introduces a theoretical framework and numerical simulations showing how magnetic fields can control surface plasmon-polariton propagation and emission in nanostructures.

Findings

Magnetic field breaks symmetry between interfaces in the waveguide.

Tuning magnetization modifies radiation emission and distribution.

Magnetic control enables dynamic manipulation of light in nanostructures.

Abstract

The dispersion relations for surface plasmon-polaritons propagating in the Voigt geometry in a metal-insulator-metal waveguide with a magneto-optically active dielectric medium are derived. The symmetry between the upper and lower interfaces is broken by the introduction of the magnetic field; the balance between the field distributions on the two interfaces can be controlled by the applied field. This control is illustrated by finite-element method numerical simulations of the field distributions around a point dipole placed in the centre of the short waveguide; it is shown that both the total emission of radiation from the cavity and the distribution of the far-field radiation can be strongly modified by tuning the magnetisation of the waveguide. This raises the novel possibility of using magnetic fields to control light propagation in nanostructures.