Extraordinary Magnetooptics in Plasmonic Crystals

TL;DR

This paper reports a novel magnetooptical plasmonic crystal that exhibits giant Faraday and Kerr effects, enabling advanced control of light for applications in telecommunications, sensing, and data storage.

Contribution

It introduces a new one-dimensional plasmonic crystal with enhanced magnetooptical effects driven by surface plasmon polaritons, demonstrating significant practical potential.

Findings

Giant Faraday and Kerr effects observed near transmission peaks

Enhancement of Kerr effect by three orders of magnitude

Potential for use in telecommunication and magnetic data storage devices

Abstract

Plasmonics has been attracting considerable interest as it allows localization of light at nanoscale dimensions. A breakthrough in integrated nanophotonics can be obtained by fabricating plasmonic functional materials. Such systems may show a rich variety of novel phenomena and also have huge application potential. In particular magnetooptical materials are appealing as they may provide ultrafast control of laser light and surface plasmons via an external magnetic field. Here we demonstrate a new magnetooptical material: a one-dimensional plasmonic crystal formed by a periodically perforated noble metal film on top of a ferromagnetic dielectric film. It provides giant Faraday and Kerr effects as proved by the observation of enhancement of the transverse Kerr effect near Ebbesen's extraordinary transmission peaks by three orders of magnitude. Surface plasmon polaritons play a decisive role in this enhancement, as the Kerr effect depends sensitively on their properties. The plasmonic crystal can be operated in transmission, so that it may be implemented in devices for telecommunication, plasmonic circuitry, magnetic field sensing and all-optical magnetic data storage.