Tunable layer-polarized anomalous Hall effect in two-dimensional 3R-GdBrI bilayer

Abstract

Layer-polarized anomalous Hall effect (LP-VHE), coupling valley-contrasting physics and layer degree of freedom, stands as a crucial development for potential applications in valleytronics. Based on first-principles calculations, taking 3R-type stacking GdBrI bilayer (3R-GdBrI) as an example, we demonstrate that the LP-VHE can be generated in a polar ferrovalley bilayer. In homoatomic interfacial 3R-GdBrI, the LP-VHE is spontaneously realized by combining electric polarization and magnetization. In hetero-atomic interfacial 3R-GdBrI, the LP-VHE can be achieved by applying an out-of-plane electric field (Egate). The Egate induces transition from anomalous valley Hall effect to LP-VHE by decreasing the asymmetric distribution of the charge density. Further calculations prove that the same effects can also be observed in ferromagnetic 3R-ScClBr bilayers. Our work provides an alternative way to construct a bilayered LP-VHE system.