RKKY interaction in graphene
  We consider RKKY interaction between two magnetic impurities in graphene. The consideration is based on the perturbation theory for the thermodynamic potential in the imaginary time representation. We analyze the symmetry of the RKKY interaction on the bipartite lattice at half filling. Our analytical calculation of the interaction is based on direct evaluation of real space spin susceptibility. We show in the Appendix, added to the published version, that the approach can be easily generalized to the case of finite temperature. 
E. Kogan
cond-mat.mes-hall cond-mat.stat-mech