Point defect induced intervalley scattering for enhancement of interlayer electron transport in bilayer MoS2 homojunction

Since the emerging of transition metal dichalcogenides (TMDCs) based van der Waals (vdW) structures, the interlayer charge transport has become an important issue towards application of these novel materials. Due to the unique layered structure of these materials, charge transport across the vdW gaps via tunneling which is governed by individual valleys with different interlayer coupling strength. On the other hand, the omnipresent point defects in TMDCs could possibly cause intervalley scattering between these valleys. In this article, we investigate the influence of point defect induced intervalley scattering on the interlayer charge transport of MoS2 homojunction by first principle calculation. We find S vacancies and Mo-S antisite defects enhance the electron interlayer transport by intervalley scattering that divert the electrons from the non-interlayer coupling K valley to strong interlayer coupling Q valley. The interlayer charge transport enhancement caused by such intervalley scattering mechanism could pave the way on understanding the interlayer charge transport in TMDCs based vdW structures.