Modeling of graphene-based field-effect transistors through a 1-D real-space approach

In this work, we present a computationally efficient approach for atomistic simulations of graphene nanoribbon (GNR), bilayer graphene (BLG) and bilayer graphene nanoribbon (BLGNR) field-effect transistors. The simulation scheme, which involves the self-consistent solutions of the non-equilibrium Green function method (NEGF) and 2-D Poisson’s equation, is based on the tight binding Hamiltonian in a 1-D real-space basis. We show that the Hamiltonian matrix for smooth edge GNRs and graphene can be expressed by 1 \(\times \) 1 size coupling matrices, which provides easy solutions for NEGF equations and largely reduces the computational time for simulation. The BLG and BLGNR can be described by the two coupled single-layer GNR Hamiltonian matrices, which allows the modeling of these devices by the same transport equations as GNR-FET with small modifications. Furthermore, the developed transport models are verified with the previously reported simulation and theoretical results.