Zitterbewegung, chirality, and minimal conductivity in graphene

TL;DR

This paper analyzes the minimal conductivity of graphene, a gapless semiconductor with massless Dirac fermions, explaining its finite conductivity at zero temperature and charge density through theoretical formulas.

Contribution

It provides a theoretical explanation for the finite minimal conductivity in graphene based on the properties of Dirac chiral fermions without scattering.

Findings

Finite conductivity arises from Dirac chiral fermions in 2D.

Conductivity is of order e^2/h at zero temperature and charge density.

The analysis uses Kubo and Landauer formulas to explain experimental observations.

Abstract

It has been recently demonstrated experimentally that graphene, or single-layer carbon, is a gapless semiconductor with massless Dirac energy spectrum. A finite conductivity per channel of order of $e^{2}/h$ in the limit of zero temperature and zero charge carrier density is one of the striking features of this system. Here we analyze this peculiarity based on the Kubo and Landauer formulas. The appearance of a finite conductivity without scattering is shown to be a characteristic property of Dirac chiral fermions in two dimensions.