Full charge incorporation in ab initio simulations of two-dimensional semiconductor-based devices

Quantum transport simulations based on the non-equilibrium Green's function formalism require accurate integration of the charges in the system. We demonstrate our implementation of a full charge integration scheme, which automatically incorporates electronic screening effects and is predicted to incorporate interface charges more correctly than the simpler excess charge approach. We first show that under certain conditions the two approaches are equivalent, e.g., for single doping type purely semiconducting devices. We then demonstrate that for devices containing metals, the two approaches may sometimes demonstrate significantly different behavior.

Automated summary

This article introduces a quantum transport simulation method based on the non-equilibrium Green's function formalism, which requires accurate integration of charges in the system. We demonstrate a full charge integration scheme that incorporates electronic screening effects and interface charges more correctly than the simpler excess charge approach. We show that under certain conditions the two approaches are equivalent, but for devices containing metals, they may demonstrate significantly different behavior.