Authors
Sameh Kessentini, Dominique Barchiesi, Cristiano D’Andrea, Andrea Toma, Nicolas Guillot, Enzo Di Fabrizio, Barbara Fazio, Onofrio M. Maragó, Pietro G. Gucciardi, Marc Lamy de la Chapelle,
Title
Gold Dimer Nanoantenna with Slanted Gap for Tunable LSPR and Improved SERS
In
The Journal of Physical Chemistry
Volume
118
Issue
6
Pages
3209–3219
Publisher
ACS Publications
Year
2014
Publisher's URL
10.1021/jp409844y
Indexed by
Abstract
We focus on improving the surface-enhanced Raman scattering (SERS) of dimer nanoantenna by tailoring the shape of the coupled nanoantennas extremities from rounded to straight or slanted ones. A numerical model based on the discrete dipole approximation method—taking into account periodicity, adhesion layer, and roughness—is first validated by comparison with localized surface plasmon resonance (LSPR) and SERS experiments on round-edged dimer nanoantennas and then used to investigate the effect of the straight or slanted gap in the dimer antenna. Simulations show that both LSPR and SERS can be tuned by changing the gap slanting angle. The SERS enhancement factor can also be improved by 2 orders of magnitude compared to the one reached using a rounded gap. Therefore, the slanting angle can be used as a new control parameter in the design of SERS substrates to guarantee stronger field confinement and higher sensitivity, especially as its feasibility is demonstrated.
Affiliations
Offprint