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arXiv · 1808.08476

Optically driven collective spin excitations and magnetization dynamics in the Néel-type skyrmion host GaV$_4$S$_8$

P. Padmanabhan·F. Sekiguchi·R. B. Versteeg·E. Slivina·V. Tsurkan·S. Bordács·I. Kézsmárki·P. H. M. van Loosdrecht
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Abstract

GaV$_4$S$_8$ is a multiferroic semiconductor hosting magnetic cycloid (Cyc) and Néel-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.

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P. Padmanabhan, F. Sekiguchi, R. B. Versteeg, E. Slivina, V. Tsurkan, S. Bordács, I. Kézsmárki, P. H. M. van Loosdrecht. 2018-08-25. Optically driven collective spin excitations and magnetization dynamics in the Néel-type skyrmion host GaV$_4$S$_8$. https://doi.org/10.1103/physrevlett.122.107203

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