I'm going to calculate the electrical conductivity of some materials (like graphene) theoretically. Do you have any recommendations about suitable theoretical methods or can you suggest good references?
This review, http://cds.cern.ch/record/597840/files/0212268.pdf, ``Transport coefficients and quantum fields'', by G. Aarts and J. M. Martinez Resco, might be a good place to start.
I personally believe in the methods of quantum field theory which are readily applicable for graphene which is described by Dirac equation.
Graphene conductivity was calculated many times (for different configurations) by Gorbar, Gusynin and co-authors, see many of their papers in arXive. We also did it, see e.g.
Fialkovsky I. V., Vassilevich D. V.,
Faraday rotation in graphene,
Eur. Phys. J. B (2012) 85: 384, arXiv:1203.4603v3 [cond-mat.mes-hall]
Fialkovsky I. V., Vassilevich D. V.,
Quantum Field Theory in Graphene,
Int. J. Mod. Phys. A 27, 1260007 (2012), arXiv:1111.3017v2 [hep-th]