Nonvolatile electrical control of the electronic and valleytronic properties by ferroelectricity in the VSi2P4/Al2S3 van der Waals heterostructure

Abstract

In this paper, based on first-principles theory, we investigated the properties of the multiferroic VSi₂P₄/Al₂S₃ van der Waals (vdW) heterostructure (HS), in which VSi₂P₄ and Al₂S₃ are ferromagnetic (FM) and ferroelectric (FE) materials, respectively. Our results show that the properties of the VSi₂P₄ layer can be effectively manipulated by reversing the ferroelectric polarized state of the Al₂S₃ layer (P↑ and P↓). Specifically, for P↓ Al₂S₃, VSi₂P₄ preserves the semiconductor nature and the intrinsic valley polarization in the conduction band. However, for P↑ Al₂S₃, the VSi₂P₄ sublayer is changed to a half-metal, and the valley polarization in the conduction band is submerged in trivial bands. Our findings provide an effective way for nonvolatile electrical control of the electronics and valleytronics of 2D ferromagnetic materials.