Análise numérica de sensor de ressonância plasmônica de superfície baseado em grafeno na faixa de terahertz

Abstract

This work proposes a Terahertz plasmonic refraction index sensor based on Single-Layer Graphene operating as a refractometer in the Terahertz range. The configuration used is Kretschmann, where one of the variables that monitors the reflectivity is the chemical potential. The sensor was theoretically analyzed by the finite element method (FEM), using a bidimensional-based model structure. In it, the reflectivities and the field distributions were calculated for different parameters, such as sample thickness, operating frequency, incidence angle, chemical potential variation and electrical permittivity. Firstly, a study was made to determine the best operating frequency, the sensor’s angle of incidence and minimum sample thickness that the sample should have Subsequently, the numerical model was compared with the analytical model obtained through two literatures.. From the numerical results, parametric analyzes were performed to verify variations in sensitivity, full width at half maximum (FWHM) and resolution, all parameters of device quality. Numerical results are compared with theoretical concepts available in the literature and in recently published works.