Finite difference time domain (FDTD) simulations are used to find the electric field intensity at the center of a cluster
of plasmonic nanoparticles irradiated by a planewave source. We use an iterative optimization algorithm to maximize the
electric field intensity. The resulting optimized configurations are found to be non-symmetric and non-intuitive, and
cannot be obtained by analytical calculation methods. Experimentally, we investigate a novel technique using angle
evaporation to produce plasmonic nanostructures with gap sizes of 1-2 nm. We evaluate the plasmonic activity of these
nanoparticles both experimentally using surface enhanced Raman spectroscopy (SERS) measurements and theoretically
using FDTD simulations. These simulations predict an electric field intensity enhancement of 82,400 at the center of the
nanoparticle dimer, and an electromagnetic SERS enhancement factor of 109-1010.
FDTD simulations are performed on two-dimensional clusters of plasmonic metal nanoparticles in response to incident planewave irradiation. Using an iterative optimization algorithm, we determine the spatial configuration of the nanoparticles that gives the maximum electric field intensity at the center of the cluster. The optimum configurations of these clusters have mirror symmetry about the axis of planewave propagation, but are otherwise non-symmetric and non-intuitive. The optimized electric field intensity increases monotonically with the number of nanoparticles in the cluster, producing surface enhanced Raman spectroscopy (SERS) enhancements that are 25 times larger than linear chains of nanoparticles and 6 million times larger than the incident electromagnetic field.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.