Efficient spin injection and giant magnetoresistance inFe/MoS2/Fejunctions

Abstract

We demonstrate giant magnetoresistance in $\mathrm{Fe}/\mathrm{MoS}{}_{2}/\mathrm{Fe}$ junctions by means of ab initio transport calculations. We show that junctions incorporating either a monolayer or a bilayer of $\mathrm{MoS}{}_{2}$ are metallic and that Fe acts as an efficient spin injector into $\mathrm{MoS}{}_{2}$ with an efficiency of about 45%. This is the result of the strong coupling between the Fe and S atoms at the interface. For junctions of greater thickness, a maximum magnetoresistance of $\ensuremath{\sim}$300% is obtained, which remains robust with the applied bias as long as transport is in the tunneling limit. A general recipe for improving the magnetoresistance in spin valves incorporating layered transition metal dichalcogenides is proposed.