Enhanced Magnetoelectric Coupling in Van der Waals Heterostructures

Multiferroic materials exhibiting coupled ferroelectric (FE) and ferromagnetic (FM) properties are vital for multifunctional devices. However, achieving enhanced magnetoelectric coupling remains a notable challenge. The emergence of ultra-thin, two-dimensional (2D) van der Waals (vdW) FE and magnetic materials offers unique opportunities to create artificial multiferroics through heterostructures. In this presentation, I showcase enhanced magnetoelectric couplings in two vdW heterostructures: CrI3/Sc2Co2 and CrCl3/CuCrP2S6. Our first-principles simulations predict that reversing FE polarization can efficiently switch their interlayer FM and antiferromagnetic (AFM) orders. Further analysis reveals that these observed magnetoelectric couplings stem from rich proximity mechanisms. In the first heterostructure, the magnetoelectric coupling is achieved through substantial changes in band alignment and subsequent charge transfer (doping effect). In the second heterostructure, the system remains insulating throughout the process, and the mechanism primarily arises from the unique spin local field effect on interlayer exchange interactions. These results underscore the promising prospects of coupling electric polarization with correlated magnetic orders through the unique proximity physics in vdW multiferroic heterostructures.