Semiempirical model for nanoscale device simulations

Abstract

We present a semiempirical model for calculating electron transport in atomic-scale devices. The model is an extension of the extended Hückel method with a self-consistent Hartree potential that models the effect of an external bias and corresponding charge rearrangements in the device. It is also possible to include the effect of external gate potentials and continuum dielectric regions in the device. The model is used to study the electron transport through an organic molecule between gold surfaces, and it is demonstrated that the results are in closer agreement with experiments than ab initio approaches provide. In another example, we study the transition from tunneling to thermionic emission in a transistor structure based on graphene nanoribbons.

Atomic-scale model for the contact resistance of the nickel-graphene interface

“…The system is not relaxed, and the transmission coefficient is calculated using an extended Hückel model. 20 The model in Ref. 20 allows for self-consistently adjusting the onsite elements, but in order to have the most simple model this option is not used in this study.…”

Electron-phonon scattering from Green's function transport combined with molecular dynamics: Applications to mobility predictions

“…Atomistic modeling of electronic devices is typically carried out using nonequilibrium Green's function (NEGF) theory in combination with either DFT [9] or tight-binding methods [10,11]. EPC can be rigorously included in NEGF using perturbation theory.…”

Nanoelectronic Devices Based on Carbon Nanotubes

“…A combination of the Landauer approach with the non-equilibrium Green function (NEGF) method is now widely used in the analysis and design of nanoscale devices. Quantum transport in nanotubes and other nanoelectronic devices is described in more details in (Wong and Akinwande, 2011;Javey and Kong, 2010;Stokbro et al, 2010;Blom and Stokbro, 2011;Datta, 2005;Nazarov and Blanter, 2009). …”