Leveraging Nanoscale Plasmonic Modes to Achieve Reproducible Enhancement of Light
journal contributionposted on 13.10.2010, 00:00 authored by Ryan T. Hill, Jack J. Mock, Yaroslav Urzhumov, David S. Sebba, Steven J. Oldenburg, Shiuan-Yeh Chen, Anne A. Lazarides, Ashutosh Chilkoti, David R. Smith
The strongly enhanced and localized optical fields that occur within the gaps between metallic nanostructures can be leveraged for a wide range of functionality in nanophotonic and optical metamaterial applications. Here, we introduce a means of precise control over these nanoscale gaps through the application of a molecular spacer layer that is self-assembled onto a gold film, upon which gold nanoparticles (NPs) are deposited electrostatically. Simulations using a three-dimensional finite element model and measurements from single NPs confirm that the gaps formed by this process, between the NP and the gold film, are highly reproducible transducers of surface-enhanced resonant Raman scattering. With a spacer layer of roughly 1.6 nm, all NPs exhibit a strong Raman signal that decays rapidly as the spacer layer is increased.