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arXiv · 1010.4393

Atomistic quantum transport modeling of metal-graphene nanoribbon heterojunctions

I. Deretzis·G. Fiori·G. Iannaccone·A. La Magna
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Abstract

We calculate quantum transport for metal-graphene nanoribbon heterojunctions within the atomistic self-consistent Schrödinger/Poisson scheme. Attention is paid on both the chemical aspects of the interface bonding as well the one-dimensional electrostatics along the ribbon length. Band-bending and doping effects strongly influence the transport properties, giving rise to conductance asymmetries and a selective suppression of the subband formation. Junction electrostatics and p-type characteristics drive the conduction mechanism in the case of high work function Au, Pd and Pt electrodes, while contact resistance becomes dominant in the case of Al.

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I. Deretzis, G. Fiori, G. Iannaccone, A. La Magna. 2010-10-21. Atomistic quantum transport modeling of metal-graphene nanoribbon heterojunctions. https://doi.org/10.1103/physrevb.82.161413

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