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arXiv · 2301.05577

Optical-controlled ultrafast dynamics of skyrmion in antiferromagnets

S. H. Guan·Y. Liu·Z. P. Hou·D. Y. Chen·Z. Fan·M. Zeng·X. B. Lu·X. S. Gao·M. H. Qin·J. M. Liu
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Abstract

Optical vortex, a light beam carrying orbital angular momentum (OAM) has been realized in experiments, and its interactions with magnets show abundant physical characteristics and great application potentials. In this work, we propose that optical vortex can control skyrmion ultrafast in antiferromagnets using numerical and analytical methods. Isolated skyrmion can be generated/erased in a very short time ~ps by beam focusing. Subsequently, the OAM is transferred to the skyrmion and results in its rotation motion. Different from the case of ferromagnets, the rotation direction can be modulated through tuning the light frequency in antiferromagnets, allowing one to control the rotation easily. Furthermore, the skyrmion Hall motion driven by multipolar spin waves excited by optical vortex is revealed numerically, demonstrating the dependence of the Hall angle on the OAM quantum number. This work unveils the interesting optical-controlled skyrmion dynamics in antiferromagnets, which is a crucial step towards the development of optics and spintronics.

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physics.opticscond-mat.mes-hallphysics.app-ph

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S. H. Guan, Y. Liu, Z. P. Hou, D. Y. Chen, Z. Fan, M. Zeng, X. B. Lu, X. S. Gao, M. H. Qin, J. M. Liu. 2023-06-02. Optical-controlled ultrafast dynamics of skyrmion in antiferromagnets. https://doi.org/10.1103/physrevb.107.214429

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