Effects of electron-hole asymmetry near the Dirac point in graphene

TL;DR

This paper investigates how electron-hole asymmetry and disorder affect the electronic properties of graphene near the Dirac point, including effects of impurities, phonons, and temperature.

Contribution

It provides a detailed analysis of electron-hole asymmetry in graphene considering disorder, impurity scattering, and electron-phonon interactions using theoretical models.

Findings

Asymmetry influences conductivity near the Dirac point.

Impurity scattering affects self-energy corrections in graphene.

Temperature impacts compressibility and conductivity.

Abstract

In the recent years many researches were performed about graphene. Graphene is always considered a half metal or a zero gap semiconductor. In the last year new experiments were done about graphene on boron nitride and they obtained an insulating behaviour and a power law for conductivity at the charge neutrality point (CNP) or Dirac point (DP)(PhysRevLett.110.216601). In this work we will explore the electron-hole asymmetry and the disorder in graphene. In particular we analyze the asymmetry in the ordered phase, considering thermal doping at half filling and with a non zero chemical potential. After that we use the self consistent Born approximation for calculating the self energy correction from impurity scattering. Furthermore we shall analyze the electron-phonon interaction, using the deformation potential model for obtaining the temperature dependence for the compressibility. Finally we will speculate about temperature dependence of conductivity.