PROFILES OPTIMIZATION AND CHARACTERIZATIONS OF 1D AND 2D PLASMONIC CRYSTALS

Abstract

Surface plasmon polariton is surface electromagnetic waves that propagate parallel along a metal/dielectric interface through a 1D or 2D periodic structures. Since the polaritons wave is confined at interface, the surface plasma polariton (SPP) is very sensitive to any changes on this boundary that directly change the effective refractive index of the system. This enables us to do some variations to control the SPP, i.e., modifying the metallic nanostructure of the plasmonic crystal (PCL) to vary the effective refractive index. Interference lithography has been widely used to produce different orders of periodic/array of nanostructures. It also has been used as the most economist and efficient way to provide 1D and 2D plasmonic crystals over large area. However, this method suffers from nonlinear processes involved in the manufacture of nominally sinusoidal surface relief diffraction gratings that can introduce distortions. Such distortions may dramatically affect both the specular reflectivity and diffracted efficiencies from plasmonic crystals. Therefore, the quality of surface profile and some geometrical parameters need to be controlled in order to optimize the coupling condition. This will lead us to the understanding of the fundamental geometrical contribution to obtain the field enhancement and variety of profile qualities.