Spin‐Dependent Electronic Structure and Magnetic Properties of 2D JANUS Mn 2 CFCl/CuBiP 2 Se 6 Van Der Waals Multiferroic Heterostructures

Abstract 2D van der Waals (vdW) multiferroic heterostructures have potential applications in novel 2D spintronic devices. Here, the electronic structure and magnetic anisotropy of 2D vdW multiferroic Mn 2 CFCl/CuBiP 2 Se 6 heterostructures are investigated systematically by first‐principles calculations. Ferroelectric material CuBiP 2 Se 6 has a built‐in electric field. Mn 2 CFCl is a half‐metallicity with ferromagnetic. The plane average potential difference of Mn 2 CFCl/CuBiP 2 Se 6 heterostructures is 0.02 eV in P↓ state and 0.39 eV in P↑ state. The magnetic anisotropy of P↑ and P↓ states is shown perpendicular magnetic anisotropy (PMA). The P↑ state exhibits metallic character with the biaxial strain of 4%, −6%, while the P↓ state demonstrates half‐metallicity at a strain of 2%, 4%, 6%. The P↑ state shows PMA at the different biaxial strain. However, the P↓ state shows PMA at biaxial strain of −2%, −4%, and 6%, which shifts PMA to in‐plane magnetic anisotropy at −6%, 2%, and 4%. These tunable electronic structure and magnetic anisotropy suggest that the 2D multiferroic Mn 2 CFCl/CuBiP 2 Se 6 vdW heterostructures have potential applications in spintronic devices.