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Chirality and Correlations in Graphene

Yafis Barlas·T. Pereg-Barnea·Marco Polini·Reza Asgari·A. H. MacDonald
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Abstract

Graphene is described at low-energy by a massless Dirac equation whose eigenstates have definite chirality. We show that the tendency of Coulomb interactions in lightly doped graphene to favor states with larger net chirality leads to suppressed spin and charge susceptibilities. Our conclusions are based on an evaluation of graphene's exchange and random-phase-approximation (RPA) correlation energies. The suppression is a consequence of the quasiparticle chirality switch which enhances quasiparticle velocities near the Dirac point.

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Yafis Barlas, T. Pereg-Barnea, Marco Polini, Reza Asgari, A. H. MacDonald. 2007-06-05. Chirality and Correlations in Graphene. https://doi.org/10.1103/physrevlett.98.236601

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