The role of frequency dependence in dynamical gap generation in graphene

TL;DR

This paper investigates how frequency dependence affects the dynamical gap generation in graphene using a non-perturbative Dyson-Schwinger approach, revealing a significant reduction in the critical coupling when including dynamical screening effects.

Contribution

It introduces a comprehensive frequency-dependent analysis of gap generation in graphene, improving upon previous models by self-consistently including dynamical screening effects.

Findings

Critical coupling is substantially reduced with dynamical screening.

Frequency dependence significantly influences gap formation.

Non-perturbative Dyson-Schwinger approach provides new insights.

Abstract

We study the frequency dependencies of the fermion and photon dressing functions in dynamical gap generation in graphene. We use a low energy effective QED-like description, but within this approximation, we include all frequency dependent effects including retardation. We obtain the critical coupling by calculating the gap using a non-perturbative Dyson-Schwinger approach. Compared to the results of our previous calculation [1] which used a Lindhard screening approximation instead of including a self-consistently calculated dynamical screening function, the critical coupling is substantially reduced.