Dzyaloshinskii-Moriya interaction and magnetic skyrmions induced by curvature

Realizing sizable Dzyaloshinskii-Moriya interaction (DMI) in intrinsic two-dimensional (2D) magnets with-out 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 CrBr2 and 2D MnSe2 magnets by using first-principles calculations. We find that DMIs in curved CrBr2 and MnSe2 can be efficiently controlled by varying the curvature c, where c is defined as the ratio between the height h and the length l of the curved structure. Moreover, we unveil that the dependence of first-principles calculated DMI on curvature c can be well described by the three-site Fert-Levy 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 an avenue for inducing DMI and chiral spin textures in simple 2D magnets via curvature.