Interfacial anisotropy modulation enables spin textures transitions in V3I8/VI2 heterostructure

Abstract

This work demonstrates that weak interlayer exchange coupling in lattice-matched V3I8/VI2 van der Waals heterostructures simultaneously preserves monolayer-inherent antiferromagnetic (VI2, 120°-AFM) and ferromagnetic (V3I8) orders while enabling emergent control of topological spin textures. Structural relaxation reveals 0.23% lattice mismatch with AA ↔ AB stacking transitions. Subsequently, interfacial charge transfer of 0.012 electrons per unit cell induces a weak built-in electric field that downshifts the band edges of VI2 without altering heterostructure's semiconducting nature, characterized by a 0.192 eV gap. Crucially, the magnetic anisotropy energy (MAE) of V3I8 decreases by 83% from 0.421 to 0.071 meV/atom, while the easy-axis orientation is retained. In addition, via atomistic simulations, we confirm that zero-field stabilization of Néel-type skyrmions at 0 K and bidirectional field-driven transitions (Bz↔Bx) between skyrmions and bimerons below 49 K together establish a design rule for topological spintronic devices.