Nanoscale thickness-dependent dielectric function for Au thin films”

LUIS J. MENDOZA HERRERA; MYRIAM C. TABALDI; DANIEL C. SCHINCA; LUCÍA B. SCAFFARDI

San José

Congreso; RIAO OPTILAS 2023; 2023

Red Iberoamericana de Óptica

Metallic materials at the nanoscale (nanoparticles, nanowires and thin films) have relevantroles in different applications. Metal NPs were first studied for their applications in biologyand medicine. Metal nanowires found applications in solar cells, while metal films areused in development of plasmonic sensors and plasmonic waveguides.Applications are based on the optical properties at the nanoscale, which in turn, are based onknowledge of the size dependent dielectric function properties. In this work, it is obtained expressions for the damping constant () and plasma frequency () in terms of the film thicknesses. This dependence was determined by using a previously developed method based on Drude model and considering experimental refractive index values for Au thin films.Finally, the complex dielectric function for Au was determined based on the expressionsderived for the film thickness dependence of the damping constant and plasma frequency.