Effects of edge chemistry doping on graphene nanoribbon mobility

TL;DR

This study investigates how edge chemistry doping affects the electron mobility in graphene nanoribbons, revealing dependencies on width, doping density, and carrier density through advanced simulations.

Contribution

It provides a detailed analysis of edge doping effects on GNR mobility using ab initio and tight binding simulations combined with quantum transport modeling.

Findings

Mobility scales linearly with GNR width for widths >4nm.

Mobility decreases with higher edge doping concentration.

Mobility decreases as carrier density increases.

Abstract

Doping of semiconductor is necessary for various device applications. Exploiting chemistry at its reactive edges was shown to be an effective way to dope an atomically thin graphene nanoribbon (GNR) for realizing new devices in recent experiments. The carrier mobility limited by edge doping is studied as a function of the GNR width, doping density, and carrier density by using ab initio density functional and parameterized tight binding simulations combined with the non-equilibrium Green's function formalism for quantum transport. The results indicate that for GNRs wider than about 4nm, the mobility scales approximately linearly with the GNR width, inversely proportional to the edge doping concentration and decreases for an increasing carrier density. For narrower GNRs, dependence of the mobility on the GNR width and carrier density can be qualitatively different.