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arXiv · 1305.6334

Conductivity of Coulomb interacting massless Dirac particles in graphene: Regularization-dependent parameters and symmetry constraints

G. Gazzola·A. L. Cherchiglia·L. A. Cabral·M. C. Nemes·Marcos Sampaio
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Abstract

We compute the Coulomb correction $\mathcal{C}$ to the a. c. conductivity of interacting massless Dirac particles in graphene in the collisionless limit using the polarization tensor approach in a regularization independent framework. Arbitrary parameters stemming from differences between logarithmically divergent integrals are fixed on physical grounds exploiting only spatial $O(2)$ rotational invariance of the model which amounts to transversality of the polarization tensor. Consequently $\mathcal{C}$ is unequivocally determined to be $(19- 6π)/12$ within this effective model. We compare our result with explicit regularizations and discuss the origin of others results for $\mathcal{C}$ found in the literature.

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G. Gazzola, A. L. Cherchiglia, L. A. Cabral, M. C. Nemes, Marcos Sampaio. 2013-11-08. Conductivity of Coulomb interacting massless Dirac particles in graphene: Regularization-dependent parameters and symmetry constraints. https://doi.org/10.1209/0295-5075%2F104%2F27002

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