Green functions in graphene monolayer with Coulomb interactions taken into account

TL;DR

This study numerically investigates the low-energy effective field model of graphene with Coulomb interactions, revealing that in the insulator phase, the Green functions are energy-independent, suggesting limitations of the model in representing real graphene.

Contribution

It provides the first numerical analysis of Green functions in a lattice discretized graphene model with Coulomb interactions, highlighting phase-dependent behaviors.

Findings

Green functions are energy-independent in the insulator phase

The effective field model may not fully capture real graphene properties

Numerical simulation confirms phase-dependent Green function behavior

Abstract

We consider the low energy effective field model of graphene monolayer. Coulomb interactions are taken into account. The model is simulated numerically using the lattice discretization with staggered fermions. The two point fermionic Green functions are calculated. We find that in the insulator phase these Green functions almost do not depend on energy. This indicates that the effective field model (in its insulator phase) does not correspond to the real graphene.