Curvature-induced magnetic anisotropy in two-dimensional magnetic semiconductor CrSBr

Curvature-induced anisotropy and effective Dzyaloshinskii–Moriya interaction (DMI) have a major impact on magnetism in curved geometries. Two-dimensional Van der Waals materials provide an ideal platform to study the effects of curvature on magnetic properties due to their flexibility. In this work, we use noncollinear-spin density functional theory (DFT) to study the magnetic properties of CrSBr as a function of curvature. We found that curvature drives a transition from a cycloidal magnetic state at higher curvatures to the azimuthal magnetization at lower curvatures, stabilized by an effective curvature-induced DMI. To explain this behavior, we apply a continuum model to distinguish the contributions from spin stiffness, anisotropy, and DMI strength, with parameters obtained from the DFT calculations. Our findings not only reveal that the curvature-induced DMI plays a crucial role in shaping the curvature-induced effective anisotropy but also highlight the crucial role of noncollinear-spin DFT in providing an accurate description of flexomagnetic coupling parameters.