Optically driven collective spin excitations and magnetization dynamics in the N\'eel-type skyrmion host GaV$_4$S$_8$

TL;DR

This study demonstrates how optical pulses can coherently excite collective spin modes in GaV$_4$S$_8$, a multiferroic material with skyrmion phases, revealing new possibilities for optical control of magnetic order.

Contribution

It introduces a novel method using time-resolved magneto-optical Kerr spectroscopy and simulations to control spin dynamics in skyrmion-hosting materials.

Findings

Optical modulation induces coherent spin excitations in skyrmion and cycloid phases.

The work provides insights into spin dynamics in anisotropic skyrmion-hosting materials.

Optical control pathways for magnetic order are demonstrated.

Abstract

GaV$_4$S$_8$ is a multiferroic semiconductor hosting magnetic cycloid (Cyc) and N\'eel-type skyrmion lattice (SkL) phases with a broad region of thermal and magnetic stability. Here, we use time-resolved magneto-optical Kerr spectroscopy and micro-magnetic simulations to demonstrate the coherent generation of collective spin excitations in the Cyc and SkL phases driven by an optically-induced modulation of uniaxial anisotropy. Our results shed light on spin-dynamics in anisotropic materials hosting skyrmions and pave a new pathway for the optical control of their magnetic order.