Giant tunnel magnetoresistance in two-dimensional van der Waals magnetic tunnel junctions: Ag/CrI3/MoSi2N4/CrI3/Ag

With intrinsic magnetism, two-dimensional (2D) CrI3 has attracted tremendous interest because of the potential application in magnetic devices of smaller size. We propose to use 2D MoSi2N4 material, which has remarkable stability, excellent electronic properties, and high mobility, as tunnel barrier in vertical magnetic tunnel junction (MTJ), and demonstrate that it is able to generate a giant tunnel magnetoresistance (TMR) over 105% when integrated with CrI3 ferromagnetic layers and Ag electrodes. Combining with density-functional theory and nonequilibrium Green's function approach, we systematically investigate the electron transmission, band structures, and projected local density of states and elaborate the transmission mechanism. The TMR and spin injection efficiency maintain high values below 0.25 V. These results indicate that MoSi2N4 is a promising barrier material in future 2D vertical MTJs and provide important guidance for designing devices.