Manipulation of magnetic topological textures via perpendicular strain and polarization in van der Waals magnetoelectric heterostructure

Multi-functional manipulation of magnetic topological textures such as skyrmions and bimerons in energy-efficient ways is of great importance for spintronic applications, but still being a big challenge. Here, by first-principles calculations and atomistic simulations, the creation and annihilation of skyrmions/bimerons, as key operations for the reading and writing of information in spintronic devices, are achieved in van der Waals magnetoelectric CrISe/In2Se3 heterostructure via perpendicular strain or electric field without external magnetic field. Besides, the bimeron-skyrmion conversion, size modulation and the reversible magnetization switching from in-plane to out-of-plane could also be realized in magnetic-field-free ways. Moreover, the topological charge and morphology can be precisely controlled by a small magnetic field. The strong Dzyaloshinskii-Moriya interaction and tunable magnetic anisotropy energy in a wide window are found to play vital roles in such energy efficient multi-functional manipulation, and the underlying physical mechanisms are elucidated. Our work predicts the CrISe/In2Se3 heterostructure being an ideal platform to address this challenge in spintronic applications, and theoretically guides the low-dissipation multi-functional manipulation of magnetic topological textures.Comment: 7 pages, 5 figure

Frustration-induced magnetic bimerons in transition metal halide CoX2 (X = Cl, Br) monolayers

With the field of two-dimensional (2D) magnetic materials expanding rapidly, noncollinear topological magnetic textures in 2D materials are attracting growing interest recently. As the in-plane counterpart of magnetic skyrmions, magnetic bimerons have the same topological advantages, but are rarely observed in experiments. Employing first-principles calculations and Monte Carlo simulations, we predict that the centrosymmetric transition metal halide CoX2 (X = Cl, Br) monolayers can be promising candidates for observing the frustration-induced bimerons. These bimerons crystallize into stable triangular lattice under an appropriate magnetic field. Compared to the skyrmions driven by the Dzyaloshinskii-Moriya interaction or the long-ranged magnetic dipole-dipole interactions, these frustration-induced bimerons have much smaller size and flexible tunability. Furthermore, the biaxial strain provides an effective method to tune the frustration and thereby to tune the bimeron lattice. In detail, for CoCl2 monolayer, tensile strain can be applied to generate bimeron lattice, further shrink bimeron size and increase the density of bimerons. For CoBr2 monolayer with inherent bimeron lattice state, a unique orientation rotation of bimeron lattice controlled by compressive strain is predicted.Comment: 14 pages,6 figure