High-Performance Multiferroic Tunnel Junctions Based on Bilayer CuCrP ₂ S ₆

Multiferroic tunnel junctions (MFTJs) exhibit broad prospects for applications in nonvolatile memory devices owing to their diverse nonvolatile states. Conventional MFTJs are typically constructed with ferromagnetic electrodes and ferroelectric barriers; however, they are plagued by interface-related issues and stray field effects arising from the coexistence of ferromagnetic and ferroelectric materials. The advancement of van der Waals (vdW) multiferroic materials has opened up a promising avenue for the research and development of MFTJs. In this work, bilayer CuCrP2S6 (CCPS) is found to possess a ground state characterized by type-A antiferromagnetism and antiferroelectricity. To theoretically investigate the spin transport properties of the proposed MFTJs, we employed a combined approach of nonequilibrium Green’s function (NEGF) and density functional theory (DFT). We propose an MFTJ design based on the WTe2/bilayer-CCPS/h-BN/WTe2 heterostructure. Our findings demonstrate that the asymmetric electrode layers enable the realization of distinct nonvolatile states by manipulating the ferroelectric polarization and magnetic ordering of bilayer CCPS. The maximum tunneling magnetoresistance ratio and tunneling electroresistance ratio were calculated to be 584.67% and 1401.83%, respectively. These results highlight the significant potential of bilayer CCPS for applications in high-performance nonvolatile memory devices.