Computational study of quantum electron transport in ohmic edge contacts between two-dimensional materials

In-plane edge contacts can achieve lower contact resistance due to stronger orbital hybridization compared to conventional van der Waals top contacts. However, the quantitive understanding of the electron transport properties in the edge contact is still lacking. In this work, we present full-band atomistic quantum transport simulations of the Graphene/MoS₂ edge contact. A self-consistent calculation is done by simultaneously solving the Keldysh Non-equilibrium Green’s Functions formalism for the charge density and the Poisson equation for the electrostatic potential. The tight-binding parameters extracted from the Maximally-Localized Wannier Functions enable us to model such realistic structures at first-principle accuracy and minimal computational cost. We successfully reproduced the ohmic I-V characteristics as measured in the experiments. Our study could have broad implications in the design and fabrication of purely 2D metal-semiconductor junction for realizing atomically thin electronics with low-resistance contacts.