Control of electronic transport in graphene by electromagnetic dressing

TL;DR

This paper theoretically shows how strong electromagnetic fields with different polarizations can drastically alter graphene's electronic spectrum and conductivity, enabling light-controlled electronic properties.

Contribution

It introduces a novel theoretical framework for controlling graphene's electronic properties using electromagnetic dressing fields with different polarizations.

Findings

Circular polarization opens an energy gap in graphene.

Linear polarization induces anisotropic conductivity.

Conductivity can be tuned and made highly anisotropic by adjusting field parameters.

Abstract

We demonstrated theoretically that the renormalization of the electron energy spectrum near the Dirac point of graphene by a strong high-frequency electromagnetic field (dressing field) drastically depends on polarization of the field. Namely, linear polarization results in an anisotropic gapless energy spectrum, whereas circular polarization leads to an isotropic gapped one. As a consequence, the stationary (dc) electronic transport in graphene strongly depends on parameters of the dressing field: A circularly polarized field monotonically decreases the isotropic conductivity of graphene, whereas a linearly polarized one results in both giant anisotropy of conductivity (which can reach thousands of percents) and the oscillating behavior of the conductivity as a function of the field intensity. Since the predicted phenomena can be observed in a graphene layer irradiated by a monochromatic electromagnetic wave, the elaborated theory opens a substantially new way to control electronic properties of graphene with light.