Coherent electronic transport through graphene constrictions: sub-wavelength regime and optical analogies

TL;DR

This paper explores how electronic transport in graphene nanostructures exhibits optical-like behaviors, using the concept of diffraction barriers to explain phenomena such as diffraction and interference in subwavelength devices.

Contribution

It introduces the electronic diffraction barrier concept to unify the understanding of quantum transport and classical optics analogies in graphene nanodevices.

Findings

Electronic transport shows deep analogies with subwavelength optics.

Diffraction barriers effectively describe transport phenomena in graphene constrictions.

The approach provides new insights into graphene quantum dot experiments.

Abstract

Graphene two-dimensional nature combined with today lithography allows to achieve nanoelectronics devices smaller than the Dirac electrons wavelength. Here we show that in these graphene subwavelength nanodevices the electronic quantum transport properties present deep analogies with classical phenomena of subwavelength optics. By introducing the concept of electronic diffraction barrier to represent the effect of constrictions, we can easily describe the rich transport physics in a wealth of nanodevices: from Bethe and Kirchhoff diffraction in graphene slits, to Fabry-Perot interference oscillations in nanoribbons. The same concept applies to graphene quantum dots and gives new insigth into recent experiments on these systems.