All approaches to RKKY interaction in graphene are equal, but some approaches are more equal than others

E. Kogan

Published 2012-10-21, updated 2012-11-20Version 3

We show explicitly that two approaches to calculations of RKKY interaction between two magnetic impurities in graphene based on Green's functions: one using coordinate--imaginary time representation, and the other using momentum--frequency representation, give exactly the same results and none of them has to operate with diverging integrals and implement the cut-off procedure. Together with this, we claim that the first approach is more convenient for the calculations than the second one.