Modeling the excitation of graphene plasmons in periodic grids of graphene ribbons: an analytical approach

• Published in: Physical review. B 2016-11, Vol.94 (19), Article 195421
• Main Authors: Gonçalves, Paulo André Dias, Dias, E. J. C., Bludov, Yuliy V., Peres, N. M. R.
• Format: Article
• Language: English
• Subjects: Ciências Físicas; Ciências Naturais; Computer simulation; Cutting equipment; Electromagnetic radiation; Electromagnetic scattering; Excitation; Graphene; Gratings (spectra); Light diffraction; Mathematical analysis; Mathematical models; Periodic structures; Personal computers; Plasmonics; Plasmons; Reflectance; Science & Technology
• ISSN: 2469-9950; 2469-9969
• DOI: 10.1103/PhysRevB.94.195421

We study electromagnetic scattering and subsequent plasmonic excitations in periodic grids of graphene ribbons. To address this problem, we develop an analytical method to describe the plasmon-assisted absorption of electromagnetic radiation by a periodic structure of graphene ribbons forming a diffraction grating for THz and mid-IR light. The major advantage of this method lies in its ability to accurately describe the excitation of graphene surface plasmons (GSPs) in one-dimensional (1D) graphene gratings without the use of both time-consuming, and computationally-demanding full-wave numerical simulations. We thus provide analytical expressions for the reflectance, transmittance and plasmon-enhanced absorbance spectra, which can be readily evaluated in any personal laptop with little-to-none programming. We also introduce a semi-analytical method to benchmark our previous results and further compare the theoretical data with spectra taken from experiments, to which we observe a very good agreement. These theoretical tools may therefore be applied to design new experiments and cutting-edge nanophotonic devices based on graphene plasmonics. The authors thank N. Asger Mortensen for insightful and valuable comments. PADG acknowledges financial support from Fundação para a Ciência e a Tecnologia (Portugal) from grant No. PD/BI/114376/2016. NMRP and YVB acknowledge financial support from the European Commission through the project “GrapheneDriven Revolutions in ICT and Beyond” (Ref. No. 696656). This work was partially supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Financing UID/FIS/04650/2013. The Center for Nanostructured Graphene is sponsored by the Danish National Research Foundation, Project DNRF103.