Modeling extended contacts to nanotube and graphene devices

TL;DR

This paper develops models combining analytic solutions and ab initio calculations to study carrier injection in nanotube and graphene devices with metal contacts, highlighting the robustness of the results.

Contribution

It introduces a multi-scale modeling approach integrating minimal models and ab initio data for accurate transport predictions in carbon nanostructures.

Findings

Analytic solutions enable precise modeling of carrier injection.

Realistic parameters from ab initio calculations improve transport simulations.

Results are robust against interface disorder and electrode variations.

Abstract

Carrier injection into carbon nanotubes and graphene nanoribbons, contacted by a metal coating over an arbitrary length, is studied by various means: Minimal models allow for exact analytic solutions which can be transferred to the original system with high precision. Microscopic ab initio calculations of the electronic structure at the carbon-metal interface allow us to extract -- for Ti and Pd as contacting materials -- realistic parameters, which are then used in large scale tight-binding models for transport calculations. The results are shown to be robust against nonepitaxially grown electrodes and general disorder at the interface, as well as various refinements of the model.