Optical Transparency in an effective model for Graphene

TL;DR

This paper investigates how next-to-nearest neighbor interactions affect graphene's optical transparency, finding that the transparency remains robust despite these corrections, supporting the Dirac fermion model's validity.

Contribution

It provides a detailed analysis showing the robustness of graphene's optical transparency against next-to-nearest neighbor coupling effects.

Findings

Optical transparency remains unaffected by next-to-nearest neighbor interactions.

Zero-frequency optical conductivity is robust under these corrections.

Supports the Dirac fermion model for graphene's optical properties.

Abstract

Motivated by experiments confirming that the optical transparency of graphene is defined through the fine structure constant and that it could be fully explained within the relativistic Dirac fermions in 2D picture, in this article we investigate how this property is affected by next-to-nearest neighbor coupling in the low-energy continuum description of graphene. A detailed calculation within the linear response regime allows us to conclude that, somewhat surprisingly, the zero-frequency limit of the optical conductivity that determines the transparency remains robust up to this correction.