FM 2-2010 (arXiv:1001.5347)

Authors: Alessandro Giuliani, Vieri Mastropietro, Marcello Porta

Title: Anomalous behavior in an effective model of graphene with Coulomb interactions
 
Abstract: We perform a Renormalization Group analysis for an effective model of graphene with long range non-instantaneous interactions. We show that, at all orders in the renormalized expansion, the wave function renormalization diverges in the infrared with an anomalous critical exponent and the interacting Fermi velocity flows to a limit value generically smaller than the speed of light. Ward Identities imply that the effective charges have a bounded but non trivial flow.

Keywords: graphene, Dirac fermions, Coulomb interactions, Ward identities, renormalization group

Alessandro Giuliani
Dipartimento di Matematica
Università di Roma Tre
L.go S. Leonardo Murialdo 1, 00146 Roma - Italy
e-mail: giuliani AT mat DOT uniroma3 DOT it

Vieri Mastropietro
Dipartimento di Matematica
Università di Roma Tor Vergata
V.le della Ricerca Scientifica 1, 00133 Roma - Italy
e-mail: mastropi AT mat DOT uniroma2 DOT it

Marcello Porta
Dipartimento di Fisica
Università di Roma Sapienza
P.le A. Moro, 00185 Roma - Italy
e-mail: marcello DOT porta AT roma1 DOT infn DOT it