Ferroelectric Control of Polarity of the Spin‐polarized Current in Van Der Waals Multiferroic Heterostructures

Abstract Ferroelectric (FE) control of magnetism at nanoscale, for instance, FE control of the polarity of spin‐polarized current is crucial for technological advances in magnetoelectric and spintronic applications. However, this fascinating functionality has not been reported in nanoscale systems yet. Herein, a new class of FE/A‐type antiferromagnetic heterobilayer/FE van der Waals (vdW) multiferroic structures is found, in which the FE control of polarity of spin‐polarized current is found possible. Take Sc₂CO₂/CrSiTe₃/CrGeTe₃/Sc₂CO₂ heterostructure as a successful example. First‐principles calculations reveal that its polarity of half‐metallicity can be switched by flipping the FE polarization orientation. Meanwhile, device transport simulation shows that its up/down spin current transmission ratio is as large as 0.1 × 10³ at Sc₂CO₂ configuration and is only 2.6 × 10⁻³ at Sc₂CO₂ configuration in the vdW multiferroic heterostructures. Essentially, it stems from the reversible FE switch of the internal electric field across the CrSiTe₃/CrGeTe₃ heterobilayer and the FE control of the interfacial effect between Sc₂CO₂ and Cr(Si/Ge)Te₃ layers. This work opens a direction for constructing low‐energy‐dissipation, non‐volatile, and high‐sensitive spintronic devices such as spin field‐effect transistors.