Dzyaloshinskii-Moriya interaction and magnetic skyrmions induced by curvature

TL;DR

This paper demonstrates that curvature in 2D magnets can induce and control Dzyaloshinskii-Moriya interaction (DMI) and magnetic skyrmions, offering a new method for spintronics applications without external manipulation.

Contribution

The study introduces a novel approach to induce and tune DMI in 2D magnets through designed curvature, supported by first-principles calculations and spin model simulations.

Findings

Curvature controls DMI strength in 1D and 2D magnets.

DMI dependence on curvature fits the Fert-Lévy model.

Field-free magnetic skyrmions can be stabilized in curved MnSe2.

Abstract

Realizing sizeable Dzyaloshinskii-Moriya interaction (DMI) in intrinsic two-dimensional (2D) magnets without any manipulation will greatly enrich potential application of spintronics devices. The simplest and most desirable situation should be 2D magnets with intrinsic DMI and intrinsic chiral spin textures. Here, we propose to realize DMI by designing periodic ripple structures with different curvatures in low-dimensional magnets and demonstrate the concept in both one-dimensional (1D) CrBr2 and two-dimensional (2D) MnSe2 magnets by using first-principles calculations. We find that DMIs in curved CrBr2 and MnSe2 can be efficiently controlled by varying the size of curvature c, where c is defined as the ratio between the height h and the length l of curved structure. Moreover, we unveil that the dependence of first-principles calculated DMI on size of curvature c can be well described by the three-site Fert-L\'evy model. At last, we uncover that field-free magnetic skyrmions can be realized in curved MnSe2 by using atomistic spin model simulations based on first-principles calculated magnetic parameters. The work will open a new avenue for inducing DMI and chiral spin textures in simple 2D magnets via curvature.