Carrier Statistics and Quantum Capacitance of Graphene Sheets and Ribbons

TL;DR

This paper derives fundamental carrier statistics and quantum capacitance for graphene sheets and ribbons, revealing unique behaviors in 2D graphene and similarities to narrow-gap semiconductors in narrow ribbons.

Contribution

It provides new analytical results for carrier statistics and quantum capacitance in graphene structures, highlighting differences from traditional semiconductors.

Findings

Intrinsic carrier densities in 2D graphene differ from traditional semiconductors.

Very narrow ribbons exhibit behavior similar to narrow-gap semiconductors.

Quantum capacitance expressions are derived for both graphene sheets and nanoribbons.

Abstract

In this work, fundamental results for carrier statistics in graphene 2-dimensional sheets and nanoscale ribbons are derived. Though the behavior of intrinsic carrier densities in 2d graphene sheets is found to differ drastically from traditional semiconductors, very narrow (sub-10 nm) ribbons are found to be similar to traditional narrow-gap semiconductors. The quantum capacitance, an important parameter in the electrostatic design of devices, is derived for both 2d graphene sheets and nanoribbons.