Transmittance characteristics and tunable sensor performances of plasmonic graphene ribbons

Xin Yan,Lin Yuan,Tian Sang,Guofeng Yang,Yueke Wang

doi:10.1063/1.4960465

Abstract

We investigate the transmittance characteristics of graphene ribbons numerically. It is found that the transmission dips originate from the transverse and longitudinal resonances of edge graphene plasmon modes, supported by the graphene ribbon resonator. The environmental refractive index changes are detected by measuring the resulting spectral shifts of the resonant transmission dip, so the graphene ribbons can be applied to plasmonic sensor in infrared. Simulation results show that sensing performances for each resonant mode are similar, and figure of merit can be up to 6. Beside, thanks to the tunable permittivity of graphene by bias voltages, the transmittance spectra and sensor performances can be easily tuned.

Highlights

Surface plasmon polaritons (SPPs) are a kind of surface electromagnetic waves propagating along the metal or semiconductor surface.[1]
We have proposed a plasmonic graphene ribbon structure, and investigate the transmittance characteristics by Finite Element Method (FEM)
We believe the transmission dips originate from Edge GPs (EGPs) mode resonances of graphene SPPs (GPs) resonator in transverse direction and longitudinal direction

Summary

INTRODUCTION

Surface plasmon polaritons (SPPs) are a kind of surface electromagnetic waves propagating along the metal or semiconductor surface.[1] SPPs possess the characteristics of subwavelength locality and near-field enhancement, which are widely investigated in the visible region. The propagation properties of graphene SPPs (GPs) can be tuned by external gate voltages.[2,3] A number of tunable plasmonic phenomena have been studied such as energy concentrators,[4] nanofocusing,[5] polarization converters,[6] cloaking,[7,8] absorbers,[9] filters[10] and switchers.[11]. Edge GPs (EGPs) modes supported by graphene nanoribbons are proposed and investigated systematically,[12,13] which pave a new way to enhance the modal properties and enlighten the design of ultra compact device. By calculating the sensing performances of graphene ribbons structures, it is found the performance measures of the sensor vary in the same way for each resonant mode, when increasing chemical potential Ef

THE PROPOSED STRUCTURE AND MODE ANALYSIS

THE TRANSMITTANCE CHARACTERISTICS OF GRAPHENE RIBBONS

THE SENSING PERFORMANCES

CONCLUSIONS