The focusing properties of a Bessel-like beam emitted from a circular slit surrounded by a surface groove (CSSG) were explored using experimental and numerical methods. The optical properties of the light emitted from the CSSG can be enhanced by using the scattered light from the surface groove. Furthermore, different modes of cylindrical surface plasmons in the circular slit are induced by different wavelengths of incident light, and beam shapes with a single spot and doughnut are created under illumination in the ultraviolet and visible regimes, respectively. A versatile beam shape is obtained from the CSSG structure.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.