Electron Capture in van der Waals Graphene-Based Heterostructures with WS2 Barrier Layers

Abstract

We consider the capture processes of hot electrons propagating across the van der Waals heterostructures with graphene layers (GLs) and WS2 barrier layers. The capture probability of hot electrons into GLs as a function of the electron energy and the electric field as well as the capture probability averaged over the electron energy distribution are calculated accounting for their scattering on the optical phonons and on the electrons localized in GLs. Our calculations show that the total probability of these processes is rather low (less than 0.5%). Since the capture probability of hot electrons into GLs essentially determines the performance of the vertical hot-electron transistors with the GL base and the vertical hot-electron terahertz photodetectors, the obtained results support the prospects of these and other GL devices.