Atomistic simulation of a III-V p-i-n junction: Comparison of density functional and tight-binding approaches

We compare the results of calculations based on tight-binding and density functional theory (DFT) for the description of an ultra-narrow two-dimensional (2D) InAs system. We first investigate the electronic structure of the 2D system to understand the effect of different surface terminations and how they are modeled using tight-binding and DFT approaches. We next set up a gated 2D InAs p-i-n junction and calculate the transistor characteristics of the system using the two different approaches.