Large magnetoresistance in planar Fe/MoS₂/Fe tunnel junction

We report a large magnetoresistance observed in a Fe/MoS₂/Fe tunnel junction, where iron electrodes are attached to the edges of MoS₂ nanoribbon (i.e. the current is flowing in the plane of the MoS₂ 2D monolayer). Using non-equilibrium Green's functions in the framework of density functional approach, our calculations show a large magnetoresistance in Fe/MoS₂/Fe junction, with the values up to 150%. The strong coupling between states of Mo atoms at the edge of the MoS₂ monolayer and those at the Fe surface have a dramatic effect on the conductance property of the material as well as the MR of the Fe/MoS₂/Fe tunnel junction. We conclude that the Fe electrodes polarize the spin states of MoS₂ near the interface and efficiently inject carriers into MoS₂. We find that the atomically-thin spacers are metallic due to a strong hybridization between the Fe and Mo states at the interface. MoS₂ spacers of a larger width remain insulating. We also find that the magnetoresistance of thin MoS₂ ribbons (three atomic layers wide) is negative and has a small value. Notably however, as the width of the MoS₂ spacer increases, this value turns positive and increases in magnitude.