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arXiv · 1508.01809

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

Salvatore Croce
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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.

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Salvatore Croce. 2015-08-07. Effects of electron-hole asymmetry near the Dirac point in graphene. https://arxiv.org/abs/1508.01809

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