Surface plasmon-enhanced photo-magnetic excitation of spin dynamics in Au/YIG:Co magneto-plasmonic crystals

TL;DR

This paper demonstrates that surface plasmon excitation in a magneto-plasmonic crystal significantly amplifies photo-magnetic spin precession in Co-doped YIG, enabling localized, energy-efficient all-optical magnetization switching below the diffraction limit.

Contribution

It introduces a magneto-plasmonic approach for subwavelength localization and amplification of photo-magnetic excitation in dielectric YIG:Co, advancing all-optical magnetic switching technology.

Findings

Strong amplification of spin precession via surface plasmons.

Localization of excitation within 300 nm layer.

Numerical simulations match experimental results.

Abstract

We report strong amplification of photo-magnetic spin precession in Co-doped YIG employing a surface plasmon excitation in a metal-dielectric magneto-plasmonic crystal. Plasmonic enhancement is accompanied by the localization of the excitation within the 300~nm-thick layer inside the transparent dielectric garnet. Experimental results are nicely reproduced by numerical simulations of the photo-magnetic excitation. Our findings demonstrate the magneto-plasmonic concept of subwavelength localization and amplification of the photo-magnetic excitation in dielectric YIG:Co and open up a path to all-optical magnetization switching below diffraction limit with energy efficiency approaching the fundamental limit for magnetic memories.