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arXiv · 2110.15088

Curved Magnetism in CrI$_3$

Alexander Edström·Danila Amoroso·Silvia Picozzi·Paolo Barone·Massimiliano Stengel
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Abstract

Curved magnets attract considerable interest for their unusually rich phase diagram, often encompassing exotic (e.g., topological or chiral) spin states. Micromagnetic simulations are playing a central role in the theoretical understanding of such phenomena; their predictive power, however, rests on the availability of reliable model parameters to describe a given material or nanostructure. Here we demonstrate how non-collinear-spin polarized density-functional theory can be used to determine the flexomagnetic coupling coefficients in real systems. By focusing on monolayer CrI$_3$, we find a crossover as a function of curvature between a magnetization normal to the surface to a cycloidal state, which we rationalize in terms of effective anisotropy and Dzyaloshinskii-Moriya contributions to the magnetic energy. Our results reveal an unexpectedly large impact of spin-orbit interactions on the curvature-induced anisotropy, which we discuss in the context of existing phenomenological models.

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Alexander Edström, Danila Amoroso, Silvia Picozzi, Paolo Barone, Massimiliano Stengel. 2021-10-28. Curved Magnetism in CrI$_3$. https://doi.org/10.1103/physrevlett.128.177202

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