Using DNA to Design Plasmonic Metamaterials with Tunable Optical Properties*

Abstract

Due to their potential for creating “designer materials,” the 3D assembly of nanoparticle building blocks into macroscopic structures with well-defined order and symmetry remains one of the most important challenges in materials science. Furthermore, superlattices consisting of noble-metal nanoparticles (NPs) have emerged as a new platform for the bottom-up design of plasmonic metamaterials. The optical properties of gold-NP (AuNP) superlattices have been modeled using Maxwell–Garnett effective medium theory in the past. However, these superlattices were not shown to exhibit negative dielectric function properties needed for metamaterial behavior. The collective optical properties of the superlattices were then analyzed experimentally, using both UV-vis spectroscopy for ensemble measurements and optical microspectrophotometry for individual superlattice measurements.