In this study, we extended the plasmon hybridization method from a single nanoparticle to a complex planar nanostructure. This is achieved through a decomposition of the complex nanostructure into nanoparticle building blocks in its most fundamental forms. Using the gammadion planar nanostructure as an example, we validated our theory by comparing the field profile in the gammadion’s arms under the influence of an incident circularly polarized wave. This further allows us to address the origin of the plasmonics modes in the circular dichroism (CD) spectrum of the gammadion nanostructure. The use of this hybridization method provides a simple and intuitive explanation on how conductive and inductive coupling may result from complex planar nanostructures. Understanding these coupling effects open up the path to study the optical properties of a complex nanostructure. With our approach, we will be able to apply such top down hybridization studies to other complex planar structures. With knowledge of the origin of these CD modes, we can gain further insight on the modes of chiral nanostructures, allowing us to further enhance the field for ultrasensitive sensing of chiral micro and macro molecules.
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