Gold Nanoparticles on Sodium Alginate: Simulation of Optical Properties

UV-visible spectrophotometric properties of gold nanoparticles fabricated by magnetron sputtering on free-standing sodium alginate (SA) membranes have been recorded and simulated. The simulation implied the tuning of the collision frequency as well as the introduction of the Local Surface Plasmon (LSP) resonance in optical constants of the nanostructured material, which are based on a Drude-Lorentz model. The nanostructured film is treated by means of the Effective Medium Approximation. The film stack is simulated using the Generalized Transfer Matrix Method. The results show that the actual material can properly be treated, and quantitative results are obtained. A red shift in the LSP spectral position is observed for more interconnected material.