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Multiferroic tunnel junctions (MFTJs) comprised of magnetic electrodes and a ferroelectric tunnel barrier have been emerging as promising candidates for nonvolatile memory applications. The recently discovered above room-temperature van der Waals (vdW) ferromagnet Fe3GaTe2 and ferroelectric α-In2Se3 provides possibilities for constructing room-temperature vdW MFTJs. In this work, by using first-principles calculations, we investigate the spin-dependent transport in vdW MFTJs with structure of Fe3GaTe2/bilayer α-In2Se3/Fe3GaTe2. We predict a giant tunneling magnetoresistance (TMR) high up to 10 000% by switching the magnetic alignments of Fe3GaTe2 and tunneling electroresistance (TER) exceeding 300% by controlling the ferroelectric configurations of bilayer α-In2Se3 in the proposed MFTJs. Furthermore, by introducing interface asymmetry and inserting monolayer of h-BN on one interface, the TMR and TER ratios of the MFTJs can be substantially enhanced. In consequence, the multi-level resistance states can be achieved by applying magnetic and electric field in asymmetric MFTJs. Our results highlight full vdW MFTJs for their potential applications in spintronic devices, particularly in the field of multilevel nonvolatile memories. [ABSTRACT FROM AUTHOR]

• Antiferromagnetic (AFM) spintronics are the emergent research field in spintronics due to the superior properties of AFM materials in comparison to ferromagnetic (FM) materials for the applications in magnetic memory devices. So far how to effective electrical writing and reading of AFM states are the main focus in this field. • Here we propose and investigate the pure voltage controlled magnetic anisotropy (VCMA) effect in two representative AFM materials L 1 0 -MnPt and MnPd by using first-principles calculations. Our results indicate that for MnPt, at certain thickness the moderate electric field is able to switch its Néel vector between in-plane [1 0 0] and [1 1 0] direction. For MnPd, the VCMA coefficient is estimated to be around 20 fJ/V/m. • This work will attract broad research interest in voltage controlled effect in AFM films and open new perspective for effective writing and reading of the AFM state. The efficient electrical control of the magnetic states of antiferromagnets is one of the main focus in antiferromagnetic spintronics. In this work, the voltage-controlled magnetic anisotropy (VCMA) effect in two representative antiferromagnets L 1 0 -type MnPt and MnPd thin films has been investigated by employing first-principles calculations. Our results indicate that both of the MnPt and MnPd films show in-plane magnetic anisotropy and the magnetic easy axis points either along [1 0 0] or [1 1 0] direction depending on the film thickness. The applied electric field in the range of −0.3 V/Å and + 0.3 V/Å (vacuum as dielectric) leads to the change of magnetocrystalline anisotropy of both films at the order of tens of μJ/m2. Especially, for MnPt film with thickness of two unit cells on Pt(0 0 1), it shows that the moderate electric field is able to switch the in-plane magnetic easy axis between [1 0 0] and [1 1 0] directions. For MnPd thin films, the VCMA effect shows generally linear dependence on the electric field and the VCMA coefficients are estimated in the range of 2.7 to 22.6 fJ/V/m. Our calculation results may stimulate future investigations on the VCMA effect of metallic antiferromagnetic films and pave the possible applications in memory device. [ABSTRACT FROM AUTHOR]