Electronic transmission in the lateral heterostructure of semiconducting and metallic transition-metal dichalcogenide monolayers

We investigate the electronic transport property of lateral heterojunctions of semiconducting and metallic transition-metal dichalcogenide monolayers, MoSe2 and NbSe2, respectively. We calculate the electronic transmission probability by using a multiorbital tight-binding model based on the first-principles band structure. The transmission probability depends on the spin and valley degrees of freedom. This dependence qualitatively changes by the interface structure. The heterostructure with a zigzag interface preserves the spin and the valley of electrons in the transmission process. On the other hand, the armchair interface enables conduction electrons to transmit with changing the valley and increases the conductance in the hole-doped junctions due to the valley-flip transmission. We also discuss the spin and valley polarizations of electronic current in the heterojunctions.