A Comparative Study of Substrates Disorder on Mobility in the Graphene Nanoribbon: Charged Impurity, Surface Optical Phonon, Surface Roughness

TL;DR

This study investigates how different substrate disorders—surface roughness, charged impurities, and surface optical phonons—affect electron mobility in graphene nanoribbons using advanced quantum transport modeling.

Contribution

It provides a comparative analysis of substrate disorder effects on graphene nanoribbon transport, identifying the dominant scattering source.

Findings

Surface roughness significantly reduces mobility.

Charged impurities are a major scattering source.

Surface optical phonons have a lesser impact.

Abstract

The effects of substrate on the electronic properties of Graphene remains unclear. Many theoretical and experimental efforts have been done to clarify this discrepancy. In this work, we studied the electronic transport in armchair Graphene nanoribbons (AGNR) in the presence of substrate's disorder. The three main substrate's disorders -- surface roughness, charged impurity and surface optical phonon -- are investigated. Non-Equilibrium Green's function along with the tight-binding model is employed to investigate the electronic properties of Graphene Nanoribbons. The effects of these disorders are investigated individually, finally, the effects of them are compared to determine the dominant source of scattering.