Enhanced microwave-to-terahertz absorption in graphene

Konstantin Batrakov, Polina Kuzhir, Sergey Maksimenko, Nadzeya Volynets, Sofia Voronovich, Alesia Paddubskaya, Gintaras Valusis, Tommi Kaplas, Yuri Svirko, Philippe Lambin

    Research output: Contribution to journalArticlepeer-review

    Abstract

    Fresnel equations predict that an ultrathin free standing conductive film, thousands times thinner than skin depth, is capable to absorb up to 50% of incident electromagnetic radiations. In the microwave range, the same holds true for a free standing graphene sheet. We demonstrate theoretically and prove experimentally that microwave absorptance of graphene can be enhanced considerably by depositing graphene on a dielectric substrate. On the experimental side, we obtain 80% and 65% absorptance at 30GHz and 1 THz, respectively. Theory predicts that higher absorptance can be achieved with a suitable choice of the dielectric permittivity and the thickness of the substrate. Absorption can also be maximized by choosing the optimum incidence angle for s-polarized waves in free space or by working in the vicinity of the cut-off frequency of the transverse electric mode in waveguide configuration. The polarization sensitivity of the transmittance and reflectance of graphene layers can be used to tune the polarization state of the transmitted and reflected radiations.
    Original languageEnglish
    Article number123101
    Number of pages3
    JournalApplied Physics Letters
    Volume108
    DOIs
    Publication statusPublished - 21 Mar 2016

    Fingerprint Dive into the research topics of 'Enhanced microwave-to-terahertz absorption in graphene'. Together they form a unique fingerprint.

    Cite this