Electronically Tunable Perfect Absorption in Graphene
Abstract
Graphene nanostructures that support surface plasmons have been utilized to create a variety of dynamically tunable light modulators, motivated by theoretical predictions of the potential for unity absorption in resonantly-excited monolayer graphene sheets. Until now, the generally low efficiencies of tunable resonant graphene absorbers have been limited by the mismatch between free-space photons and graphene plasmons. Here, we develop nanophotonic structures that overcome this mismatch and demonstrate electronically tunable perfect absorption achieved with patterned graphenes covering less than 10% of the surface. Experimental measurements reveal 96.9% absorption in the graphene plasmonic nanostructure at 1,389 cm, with an on/off modulation efficiency of 95.9% in reflection. An analytic effective surface admittance model elucidates the origin of perfect absorption, which is design for critical coupling between free-space modes and the graphene plasmonic nanostructures.
Cite
@article{arxiv.1703.03579,
title = {Electronically Tunable Perfect Absorption in Graphene},
author = {Seyoon Kim and Min Seok Jang and Victor W. Brar and Kelly W. Mauser and Harry A. Atwater},
journal= {arXiv preprint arXiv:1703.03579},
year = {2018}
}