SURFACE PLASMON PROPERTIES ON THE TYPICAL METALS Ag AND Au DESCRIBED IN L4 MODEL

Abstract

By means of an analytical model (called L4) for the dielectric response of silver and gold we investigate properties of the surface plasmon-polaritons (SPPs). These resonant modes are of central interest in the field of plasmonics. In this work, we show the discrepancy between the familiar Drude model and the L4 for Ag and Au in the investigation of the SPP properties. We focus our interest to study different length scales which are important for SPPs in the 180-2000 nm range. The surface plasmon-poaritons are known for their ability to probe bio-molecular fluorescence and they open the way to develop sub-wavelength optics, So, the use of the above models for the permittivity of metals leads to make an evident precision on the surface wave.