TM plasmonic modes in a multilayer graphene-dielectric structure

Abstract

Optical and electronic properties of multilayer systems have been extensively studied in the last years due to its potential applications in high-performance optoelectronic and photonic devices. In particular, the role of plasmonic modes is critical in such systems leading to improvements in solar cells efficiency, detection of biosensors, Raman signal enhancement, among others. In this work, we study the plasmonic modes in a multilayer system composed of graphene layers embedded within dielectric materials. The dispersion relation of plasmonic modes is obtained by calculating the poles of reflectivity using the transfer matrix method. We show the attenuated total reflection spectra for a multilayer graphene-dielectric structure, and determine the optimum distance between the prism and the multilayer system for detecting graphene plasmons in the Otto configuration. Additional to the well-known plasmonics bands, when we consider the interband and intraband contribution of graphene's conductivity, and large wavevectors parallel to graphene's plane, all plasmonic bands have an asymptotic behavior. Besides, an upper mode emerges. Finally, it is important to highlight that the number of branches in the plasmonic relation dispersion depend on the number of graphene sheets.