Influence of the four-fermion interactions in (2+1)D massive electrons system

TL;DR

This paper studies how four-fermion interactions affect the electromagnetic properties of massive electrons in two-dimensional Dirac materials, revealing that Fermi velocity remains unaffected while mass behavior varies at high energies.

Contribution

It introduces a comprehensive analysis of four-fermion interactions within anisotropic massive PQED, highlighting their impact on electron mass but not on Fermi velocity renormalization.

Findings

Fermi velocity renormalization is unaffected by quartic fermionic interactions.

Electron mass exhibits two different asymptotic behaviors at high energy.

The study uses the $1/N$ expansion in the regime $m^2 \\ll p^2$.

Abstract

The description of the electromagnetic interaction in two-dimensional Dirac materials, such as graphene and transition-metal dichalcogenides, in which electrons move in the plane and interact via virtual photons in 3d, leads naturally to the emergence of a projected non-local theory, called pseudo-quantum electrodynamics (PQED), as an effective model suitable for describing electromagnetic interaction in these systems. In this work, we investigate the role of a complete set of four-fermion interactions in the renormalization group functions when we coupled it with the anisotropic version of massive PQED, where we take into account the fact that the Fermi velocity is not equal to the light velocity. We calculate the electron self-energy in the dominant order in the $1/N$ expansion in the regime where $m ^ 2 \ll p ^ 2$. We show that the Fermi velocity renormalization is insensitive to the presence of quartic fermionic interactions, whereas the renormalized mass may have two different asymptotic behaviors at the high-density limit, which means a high-energy scale.