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arXiv · 1711.01962

The role of frequency dependence in dynamical gap generation in graphene

M. E. Carrington·C. S. Fischer·L. von Smekal·M. H. Thoma
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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.

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M. E. Carrington, C. S. Fischer, L. von Smekal, M. H. Thoma. 2018-03-08. The role of frequency dependence in dynamical gap generation in graphene. https://doi.org/10.1103/physrevb.97.115411

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