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arXiv · 1009.3812

Dynamical current-current correlation of the hexagonal lattice and graphene

T. Stauber·G. Gómez-Santos
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Abstract

We discuss the dynamical current-current correlation function of the hexagonal lattice using a local current operator defined on a continuum-replica model of the original lattice model. In the Dirac approximation, the correlation function can be decomposed into a parallel and perpendicular contribution. We show that this is not possible for the hexagonal lattice even in the Dirac regime. A comparison between the analytical isotropic solution and the numerical results for the honeycomb lattice is given.

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T. Stauber, G. Gómez-Santos. 2010-10-23. Dynamical current-current correlation of the hexagonal lattice and graphene. https://doi.org/10.1103/physrevb.82.155412

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