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arXiv · 2009.00860

Heterobilayer moiré magnets: moiré skyrmions and the commensurate-incommensurate transition

Kasra Hejazi·Zhu-Xi Luo·Leon Balents
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Abstract

We study untwisted heterobilayers of ferromagnetic and antiferromagnetic van der Waals materials, with in particular a Dzyaloshinskii-Moriya interaction in the ferromagnetic layer. A continuum low energy field theory is utilized to study such systems. We develop a phase diagram as a function of the strength of inter-layer exchange and Dzyaloshinskii-Moriya interactions, combining perturbative and strong coupling analyses with numerical simulations using Landau-Lifshitz-Gilbert equations. Various moiré-periodic commensurate phases are found, and the commensurate-incommensurate transition is discussed. Among the commensurate phases, we observe an interesting skyrmion lattice phase wherein each moiré unit cell hosts one skyrmion.

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Kasra Hejazi, Zhu-Xi Luo, Leon Balents. 2021-08-26. Heterobilayer moiré magnets: moiré skyrmions and the commensurate-incommensurate transition. https://doi.org/10.1103/physrevb.104.l100406

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