Electronic and Transport Properties of InSe/PtTe 2 van der Waals Heterostructure.

Two-dimensional (2D) InSe and PtTe 2 have drawn extensive attention due to their intriguing properties. However, the InSe monolayer is an indirect bandgap semiconductor with a low hole mobility. van der Waals (vdW) heterostructures produce interesting electronic and optoelectronic properties beyond the existing 2D materials and endow totally new device functions. Herein, we theoretically investigated the electronic structures, transport behaviors, and electric field tuning effects of the InSe/PtTe 2 vdW heterostructures. The calculated results show that the direct bandgap type-II vdW heterostructures can be realized by regulating the stacking configurations of heterostructures. By applying an external electric field, the band alignment and bandgap of the heterostructures can also be flexibly modulated. Particularly, the hole mobility of the heterostructures is improved by 2 orders of magnitude to ∼10 3 cm 2 V -1 s -1 , which overcomes the intrinsic disadvantage of the InSe monolayer. The InSe/PtTe 2 vdW heterostructures have great potential applications in developing novel optoelectronic devices.