An accelerated algorithm for 2D simulations of the quantum ballistic transport in nanoscale MOSFETs

An accelerated algorithm for the resolution of the coupled Schrödinger/Poisson system, with open boundary conditions, is presented. This method improves the subband decomposition method (SDM) introduced in [N. Ben Abdallah, E. Polizzi, Subband decomposition approach for the simulation of quantum electron transport in nanostructures, J. Comp. Phys. 202 (2005), no. 1, 150–180]. The principal feature of the here presented model consists in an inexpensive and fast resolution of the Schrödinger equation in the transport direction, due to the application of the WKB approximation. Oscillating WKB basis elements are constructed and replace the piecewise polynomial interpolation functions used in SDM. This procedure is shown to reduce considerably the computational time, while keeping a good accuracy.