Ultrafast Optomagnonics in Ferrimagnetic Multi-Sublattice Garnets

TL;DR

This review explores ultrafast magnetization dynamics in ferrimagnetic garnets, highlighting optical control of spin modes and potential for developing high-frequency optomagnonic devices.

Contribution

It provides a comprehensive overview of ultrafast spin dynamics and optical manipulation techniques in ferrimagnetic garnets, emphasizing their application in high-frequency devices.

Findings

Detection of spin-orbit and exchange interactions using femtosecond laser pulses.

All-optical control of spin-wave and resonance modes.

Enhanced exchange resonance via surface plasmon-polaritons.

Abstract

This review discusses the ultrafast magnetization dynamics within the gigahertz to terahertz frequency range in ferrimagnetic rare-earth iron garnets with different substitutions. In these garnets, the roles of spin-orbit and exchange interactions have been detected using femtosecond laser pulses via the inverse Faraday effect. The all-optical control of spin-wave and Kaplan-Kittel exchange resonance modes in different frequency ranges is shown. Generation and localization of the electric field distribution inside the garnet through the metal-bound surface plasmon-polariton strongly enhance the amplitude of the exchange resonance modes. The exchange resonance mode in yttrium iron garnets was observed using circularly polarized Raman spectroscopy. The results of this study may be utilized in the development of a wide class of optomagnonic devices in the gigahertz to terahertz frequency range.