Investigation of efficient mathematical permittivity modeling for modal analysis of plasmonics layered structures

In this paper, we present modal analysis for plasmonics structures exhibiting light confinement in sub wavelength scale, with comparison between different mathematical models for complex dielectric constant of noble metals and finally introduce the best model that compatible with experimental results. For evaluation of this idea, we focus on different parameters such as dispersion relation, frequency dependence propagation and field penetration. All mathematical models such as Drude model, free electron gas model (FEG from Drude model without losses), Lorentz–Drude model (LD) and Brendel–Bormann model (BB) compared with complete numerical analysis based on experimental measurement from Johnson–Christy data (JC) and other reported practical data that appeared in Palik handbook. We illustrate that BB model have good agreement with experimental data and is reliable for Near Infrared, Visible and Near Ultra Violet region of electromagnetic spectra and hence, BB model for modal analysis of layered plasmonics heterostructure and complex plasmonics structures can be used.