Intrinsic Terahertz Plasmons and Magnetoplasmons in Large Scale Monolayer Graphene

TL;DR

This paper demonstrates that large-scale monolayer graphene on SiC exhibits strong terahertz plasmons and magnetoplasmons due to inhomogeneities, significantly affecting its magneto-optical properties like Faraday rotation.

Contribution

It reveals the transformation of Drude absorption into plasmonic peaks in graphene caused by nanoscale inhomogeneities, enabling plasmon-controlled magneto-optical effects.

Findings

Strong terahertz plasmonic peaks observed in graphene on SiC.

Magneto-optical response, especially Faraday rotation, is dramatically enhanced.

Graphene's cyclotron mass is much smaller than in noble metals, enabling unique phenomena.

Abstract

We show that in graphene epitaxially grown on SiC the Drude absorption is transformed into a strong terahertz plasmonic peak due to natural nanoscale inhomogeneities, such as substrate terraces and wrinkles. The excitation of the plasmon modifies dramatically the magneto-optical response and in particular the Faraday rotation. This makes graphene a unique playground for plasmon-controlled magneto-optical phenomena thanks to a cyclotron mass 2 orders of magnitude smaller than in conventional plasmonic materials such as noble metals.