▎ 摘　　要

We demonstrate a large magnetoresistance (MR) in a Co/MoS2/graphene/MoS2/Co magnetic tunnel junction by means of ab initio transport calculations. A Co electrode turns out to be an excellent spin injector for a MoS2/graphene/MoS2 barrier. The transmission spectrum, current-voltage characteristics, spin injection efficiency, and magnetoresistance are calculated for the modeled device at various bias voltages in the parallel and antiparallel magnetic configurations. A remarkable change in the transmission spectrum and a subsequent change in total current through the junction have been observed, when the relative magnetic orientations of the electrodes are altered. The huge change in current due to the change in the relative magnetic orientation of the Co electrodes produces a high magnetoresistance up to 1270%. The obtained values of the device parameters clearly indicate that a MoS2/graphene/MoS2 heterostructure would be an excellent compound for highly efficient spin-valve device applications.