Twist-Dependent Electron Charge Transfer and Transport in Phosphorene-Graphene Heterobilayers

In this work, we explore the impact of twisting (rotational stacking) on the vertical charge transfer in a graphene-phosphorene bilayer using density functional theory (DFT) and on electron transport in the plane of the bilayer using DFT and the non-equilibrium Green's function approach. We examine the bilayers with twist angles 0, 9.1, 13.3, and 44.1° and find a significant drop in charge transfer when the twist angle changes from 0 to >0°. We also identify an anisotropy of the current with regard to the twist angle, as well as direction, in the plane of the bilayer structures. Such interesting features could have an impact on enhancing the applications of two-dimensional twisted structures in nano-electronics.