Analysis of scattered field enhancement in the evanescent wave area based on the Discrete Sources Method

- The Discrete Sources Method was adjusted to consider non-spherical particle of film surface.
- The Scattering Cross-Section enhancement versus particle shape and levitation was analyzed.
- It was found that it is possible to increase the scattered intensity by several of magnitude.

In this paper the basic scheme of the Discrete Sources Method (DSM) has been modified to consider polarized light scattering by a non-spherical particle placed on a metal film deposited on a glass prism. The modified DSM model has been applied to examine the scattering properties of both metallic and dielectric particles. The Scattering Cross-Section enhancement versus particle diameter, refractive index, shape and height with respect to the film surface has been investigated. It has been demonstrated that it is possible to increase the corresponding scattered intensity by several orders choosing the appropriate shape of the gold particle and its height with respect to the film surface. Additionally, it has also been found that the DSC distribution in the incident plane shows narrow beams of the intensity directed inside a prism into the incident and specular directions.