Propagation of surface plasmon polaritons in monolayer graphene surrounded by nonlinear dielectric media

Abstract

The propagation of s-polarized surface plasmon polaritons (SPPs) was investigated in a monolayer graphene sheet surrounded by two dielectric media on each side, so that one or both sides of the media were linear or nonlinear with Kerr-type nonlinearity. The plasmonic properties including the wave propagation index neff, the penetration depth, the time-averaged power flow and the spatial profile of electric and magnetic fields were calculated for the following structures: Linear medium/Graphene/Linear medium (L/G/L), Nonlinear medium/G/L (NL/G/L) and NL/G/NL. The analysis of the nonlinear coefficient effect on the SPP properties showed that increasing the nonlinearity in NL/G/L enhanced neff. However, for a smaller difference between the nonlinearity of layers, neff decreased in NL/G/NL. By comparing between the proposed structures, it was found that while large values of neff can be obtained from L/G/L, its frequency confinement is smaller than that of NL/G/L and NL/G/NL. Furthermore, NL/G/L and NL/G/NL were able to support localized nonlinear modes, leading to enhanced frequency confinement of transverse electric (TE) waves in the presence of nonlinearity. Increasing the nonlinearity in NL/G/L confined the spatial profile of the electric field near the graphene interface, indicating the existence of surface plasmon solitons. The influence of the graphene chemical potential μ on the plasmonic properties of the structures was also investigated. In this case, it was found that the plasmonic properties can be controlled by μ. Our calculations may solve the difficulties in TE surface plasmons for application in optics and plasmonics.

Highly Confined Mid-infrared Plasmonics in Graphene-plasma Cylindrical Structures

“…In graphene plasmonics, one of the famous ways to efficiently increase the performance of the designed structure is the integration of the graphene with other tunable materials such as chiral materials [50][51][52][53][54][55][56][57], and non-linear materials [58][59][60][61][62][63][64][65][66][67][68]. Cylindrical graphene structures, which are investigated in some articles [36,37,[69][70][71][72], are one of the interesting platforms due to their potential applications.…”

Tunable Plasmonic Modes in Graphene-loaded Plasma Media

“…One of the familiar methods to enhance the performance of graphene-based devices is the integration of graphene with various smart materials such as chiral materials [43][44][45][46][47][48][49][50], and non-linear materials [51][52][53][54][55][56][57][58][59][60][61]. For instance, the authors in [44] have introduced a new platform for THz sensing applications by integrating graphene sheets with chiral materials.…”

Numerical study of vegetable oil as dielectric in the generation of surface plasmon polaritons in metal: The case of double interfaces

“…The dielectrics as passive medium supported the existence of electric field which then provided the polarization at the interface leading to the generation of collective oscillation of the surface plasmon. The usage of non-linear dielectrics was investigated to generate transverse electric (TE) modes of SPPs (Baher et al, 2018). The non-linear dielectric was also used to study spatial instability in the structure where metal was sandwiched between two dielectrics (Kumar et al, 2017).…”