Boundary treatments in non-equilibrium Green’s function (NEGF) methods for quantum transport in nano-MOSFETs

Non-equilibrium Green’s function (NEGF) is a general method for modeling non-equilibrium quantum transport in open mesoscopic systems with many body scattering effects. In this paper, we present a unified treatment of quantum device boundaries in the framework of NEGF with both finite difference and finite element discretizations. Boundary treatments for both types of numerical methods, and the resulting self-energy Σ for the NEGF formulism, representing the dissipative effects of device contacts on the transport, are derived using auxiliary Green’s functions for the exterior of the quantum devices. Numerical results with both discretization schemes for an one-dimensional nano-device and a 29 nm double gated MOSFET are provided to demonstrate the accuracy and flexibility of the proposed boundary treatments.