Nonvolatile magnetoelectric coupling in 2H-VSeTe/CuInP2S6 van der Waals heterostructure

Multiferroic materials have attracted extensive research interest due to the coupling effects between their ferroelectric and ferromagnetic properties. However, in single-phase multiferroic materials, the distinct physical origins of ferroelectricity and ferromagnetism lead to relatively weak coupling effects. To address this fundamental challenge, this study focuses on investigating the multiferroic properties in two-dimensional (2D) ferromagnetic-ferroelectric van der Waals (vdW) heterostructures. We have constructed a vdW heterostructure based on 2D Janus ferromagnetic 2H-VSeTe and ferroelectric CuInP₂S₆ monolayers, and systematically investigated its geometric configuration, electronic structure, interfacial charge transfer, magnetic properties, and multi-degree-of-freedom modulation characteristics using first-principles calculations. The results demonstrate that the VSeTe/CuInP₂S₆ vdW heterostructure exhibits semiconducting behavior with a built-in electric field at the interface directed from CuInP₂S₆ to VSeTe. Furthermore, the magnetic moment of V atoms in VSeTe shows significant enhancement. When the interface adopts the Te/S configuration, switching the ferroelectric polarization direction of CuInP₂S₆ can effectively control the orientation of VSeTe’s easy magnetization axis while simultaneously inducing a transition of CuInP₂S₆ into a switchable magnetic semiconductor state, revealing remarkable magnetoelectric coupling effects. Moreover, biaxial strain can efficiently modulate the band structure of the heterostructure, enabling a reversible semiconductor-to-metal transition. These findings provide an effective strategy for fabricating magnetoelectric coupling devices based on 2D multiferroic heterostructures.