Control Of Surface Plasmon Localization Via Self-assembly Of Silver Nanoparticles Along Silver Nanowires

摘要

Engineering of the optoelectronic properties of hybrid metal-metal nanostructures is of significant importance for the design of linear/ nonlinear optical devices, bio/chemical sensors and substrates for surface-enhanced Raman scattering (SERS) or surface-enhanced fluorescence spectroscopy.rnMetal nanoparticles (NPs) exhibit strong optical responses due to the collective excitation of the electron gas in the conduction band of the metal, localized surface plasmon resonances (LSPRs). The LSPR frequency depends strongly on the element, size, and shape of the NP. In hybrid structures of NPs, coupling of LSPRs can create regions of concentrated fields, "hot-spots", in the gaps between particles, important for high-sensitivity surface enhanced spectroscopy and high-resolution microscopy. A fundamental challenge remains the facile construction of hybrid structures exhibiting spatially controlled LSPR hot-spots. In random NP assemblies, the hot-spot position is difficult to control and more complicated lithographic techniques must be employed to get reproducible hot-spot distributions.