Writing and erasing skyrmions by single ultrafast laser pulses in monolayer Janus 2D magnets

Guangyao Miao; Yonglong Ga; Chang Liu; Pan Chen; Yichen Jin; Florian Kronast; Wenxin Cheng; Zhaoqing Ding; Kai Hu; Zongnan Zhang; Nikolai Severin; Chenxi Meng; Patil Shubhada; Sergio Valencia; Meng Meng; Qinlin Guo; Xiaoran Liu; Jiandi Zhang; Yangmu Li; Carlos-Andres Palma; Jürgen P. Rabe; Hongxin Yang; Weihua Wang; Jiandong Guo

arXiv · 2608.18278

Writing and erasing skyrmions by single ultrafast laser pulses in monolayer Janus 2D magnets

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Abstract

Skyrmions in 2D magnets are promising candidates for nonvolatile, low-power, and high-density spintronic memories. However, their experimental realization at the 2D limit remains challenging, owing to the difficulty in engineering the required chiral magnetic interactions. Here, we report the creation and direct imaging of Néel-type skyrmions in Janus 2D chromium chalcogenides using synchrotron X-ray photoemission electron microscopy, and scanning nitrogen-vacancy magnetometry, which exhibit field-free stability, nonvolatility, and size tunability. First-principles calculations and micromagnetic simulations reveal that Janus-surface-induced inversion-symmetry breaking enhances the Dzyaloshinskii-Moriya interaction, providing the microscopic mechanism for skyrmion stabilization and tunability. We further achieve reversible skyrmion writing and erasing using a single ultrafast laser pulse in a magnetic field as low as 300 Oe, demonstrating the excellent manipulability of this 2D magnetic system. These results establish Janus engineering as a route to creating and manipulating nonvolatile skyrmions in atomically thin magnets, with implications for skyrmion-based low-power spintronic devices.

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Guangyao Miao, Yonglong Ga, Chang Liu, Pan Chen, Yichen Jin, Florian Kronast, Wenxin Cheng, Zhaoqing Ding, Kai Hu, Zongnan Zhang, Nikolai Severin, Chenxi Meng, Patil Shubhada, Sergio Valencia, Meng Meng, Qinlin Guo, Xiaoran Liu, Jiandi Zhang, Yangmu Li, Carlos-Andres Palma, Jürgen P. Rabe, Hongxin Yang, Weihua Wang, Jiandong Guo. 2026-08-18. Writing and erasing skyrmions by single ultrafast laser pulses in monolayer Janus 2D magnets. https://arxiv.org/abs/2608.18278

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