Layer-Polarization Engineered Ferroelectricity and Anomalous Valley Hall Effects in van der Waals Bilayer

Layertronics, engineering the electronic properties through layer degree of freedom, has attracted considerable attention due to its promising applications in next-generation spintronic technologies. Here, by coupling sliding ferroelectricity with A-type antiferromagnetism, we demonstrate a mechanism for layer-polarization engineered electronic property through the symmetry analysis based on tight-binding (TB) model. It is found that the inversion symmetry and time-inversion symmetry breaking in the model gives rise to ferroelectricity and layer-polarized anomalous valley Hall effect. Crucially, this valley polarization is ferroelectrically switchable, enabling non-volatile electrical control of layer-resolved Berry curvature. Using first-principles calculations, this mechanism and phenomena is verified in multiferroic bilayer Janus RuClF. Our findings provide a promising platform for 2D bilayer materials, which hold great potential for applications in nanoelectronic and spintronic devices.