Magnetism in curved VSe monolayers.

Our extensive first-principles calculations on magnetic VSe monolayers reveal the curvature-induced periodic fluctuation in the magnetic moments of V atoms and the occurrence of charge density waves for curved VSe monolayers. The bending energies of curved 2H-VSe monolayers increase with increasing curvature but that of curved 1T-VSe monolayers with curvature is not monotonic. The significant periodic magnetic orders in curved VSe monolayers can be attributed to the curvature-induced modification of V-Se bond structure and periodic length variations in V-Se bonds. A phenomenological model is established to describe the relation of the total magnetic moment in one period of a curved VSe monolayer with its curvature radius and the number of hexagonal rings that forms one period. These results unveil the effect of bending deformation on magnetic van der Waals monolayers and provide a possible way to develop functional magnetic devices by mechanical design.