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arXiv · 1602.01962

The method of uniqueness and the optical conductivity of graphene: new application of a powerful technique for multi-loop calculations

S. Teber·A. V. Kotikov
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Abstract

We review the method of uniqueness which is a powerful technique for multi-loop calculations in higher dimensional theories with conformal symmetry. We use the method in momentum space and show that it allows a very transparent evaluation of a two-loop massless propagator Feynman diagram with a non-integer index on the central line. The result is applied to the computation of the optical conductivity of graphene at the infra-red Lorentz invariant fixed point. The effect of counter-terms is analysed. A brief comparison with the non-relativistic case is included.

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S. Teber, A. V. Kotikov. 2016-02-05. The method of uniqueness and the optical conductivity of graphene: new application of a powerful technique for multi-loop calculations. https://doi.org/10.1134/s004057791703014x

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