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arXiv · 1906.04336

Magnetic Skyrmion State in Janus Monolayers of Chromium Trihalides Cr(I,X)3

Changsong Xu·Junsheng Feng·Hongjun Xiang·L. Bellaiche
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Abstract

Magnetic skyrmions are nano-scale spin structures that are promising for ultra-dense memory and logic devices. Recent progresses in two-dimensional magnets encourage the idea to realize skyrmionic states in freestanding monolayers. However, monolayers such as CrI3 lack Dzyaloshinskii-Moriya interactions (DMI) and thus do not naturally exhibit skyrmions but rather a ferromagnetic state. Here we propose the fabrication of Cr(I,X)3 Janus monolayers, in which the Cr atoms are covalently bonded to the underlying I ions and top-layer Br or Cl atoms. By performing first-principles calculations and Monte-Carlo simulations, we identify strong enough DMI, which leads to not only helical cycloid phases, but also to intrinsic skyrmionic states in Cr(I,Br)3 and magnetic-field-induced skyrmions in Cr(I,Cl)3.

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Changsong Xu, Junsheng Feng, Hongjun Xiang, L. Bellaiche. 2019-06-28. Magnetic Skyrmion State in Janus Monolayers of Chromium Trihalides Cr(I,X)3. https://doi.org/10.1103/physrevb.101.060404

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