Enhancing light absorption in graphene with plasmonic lattices

¹ Instituto de Física, Universidad Nacional Autónoma de México - Apartado Postal 20-364, México Distrito Federal 01000, México
² Center for Nanophotonics, AMOLF, c/o Philips Research Laboratories - High Tech Campus 4, 5656 AE Eindhoven, The Netherlands
³ Dutch Institute for Fundamental Energy research DIFFER - P.O. Box 6336, 5600 HH Eindhoven, The Netherlands
⁴ Department of Applied Physics, Eindhoven University of Technology - P.O. Box 513, 5600 MB Eindhoven, The Netherlands

^(b) pirruccio@fisica.unam.mx

Received: 19 May 2017
Accepted: 24 August 2017

Abstract

We present a novel strategy based on metallic arrays of nanoparticles for enhancing the optical absorption in a monolayer of graphene. The collective resonances sustained by the metallic array and arising from the radiative coupling of localized surface plasmon resonances favour the interaction between the graphene layer and the light distributed in the structure. We measure the dispersion diagram of the allowed hybrid plasmonic-photonic modes and we calculate that one of these modes leads to an enhancement of the optical absorption of graphene by a factor 7. We propose to exploit this result for the rational design of graphene-based photodetectors.