Numerical simulation of half optical vortices generation by dipolar particles

Abstract

Fractional optical vortex is a relatively new research area compared to full-optical vortex. Like full-optical vortex, fractional optical vortex can carry an orbital angular momentum. Hence, the vortex has been expected to be applied in large number of other research fields such as optical communication and optical tweezer where full-optical vortex can be applied. Although various methods to generate full-optical vortices have been studied and introduced, there are fewer methods mainly for generating fractional optical vortices.

The objectivity of this study is to simulate the generation of half optical vortices by scattering incident lights using an array of multiple dielectric spheres. The properties such as radius and permittivity of each sphere of the array were determined by numerical process. A number of array models with different characteristics based on the numerical process were tested by simulation. From the study, we demonstrated that fractional optical vortex can be generated by the array model. Also, we observed the relationship between characteristics of the array and the vortex. Such finding has particular significance in obtaining fractional optical vortices with different characteristic, which would contribute to related further research.