RESUMEN
Ferromagnetic order in two-dimensional (2D) van der Waals crystals has been attracting much attention recently. Remarkably, room temperature metallic ferromagnetism is realized in 2D Fe3GeTe2. Here we design a monolayer (ML) Fe3GeTe2 spin-valve device by attaching two ends to ferromagnetic electrodes and applying a magnetic field to these ferromagnetic electrodes. We investigate the spin-involved transport characteristics of such a spin valve by using ab initio quantum transport simulation. A high magnetoresistance of â¼390% is obtained and significantly increased to 450-510% after the gates are introduced. The magnetoresistance of the ML Fe3GeTe2 spin valve is insensitive to the strain modulation. Our study provides a potential option for magnetic storage applications and will motivate further studies in spintronics based on this class of materials.
RESUMEN
The recent development of two-dimensional magnetic and sliding-ferroelectric van der Waals (vdW) materials opens a new way to realize vdW sliding multiferroic tunnel junctions (MFTJs) for low-power nonvolatile memory applications. Here, we propose and investigate full electrical control of four nonvolatile resistance states in sliding MFTJs, Au/CrI3/bilayer h-BN/CrI3-MnBi2Te4/Au, via first principles. We found four stable states associated with different polarization orientations in bilayer h-BN and magnetization alignment in two CrI3 magnetic layers, which can be controlled purely by electrical voltage and current, respectively. The MFTJ has a giant tunneling magnetoresistance (TMR) of â¼10 000% (2000% in the presence of SOC) and a sizeable tunneling electroresistance (TER) of â¼70%. The write performance is explored by spin-transfer-torque calculations which show an impressive low critical current (â¼1.5 × 1010 A m-2) to switch the magnetization of the free layer of CrI3, while antiferromagnetic MnBi2Te4 pins the reference layer with a large interfacial exchange coupling.