Coating effect on optical resonance of plasmonic nanobowtie antenna
Abstract
We investigate the effect of dielectric coating on the optical resonance of metallic bowtie nanoantennas, both theoretically and experimentally. The resonance wavelengths of the nanostructures measured by means of dark-field scattering spectroscopy are in excellent agreement with our theoretical calculations. The resonance wavelength is redshifted as the thickness of the coating layer increases, which is attributed to a longer effective optical path due to the larger refractive index of the coating than that of the air.
- Publication:
-
Applied Physics Letters
- Pub Date:
- August 2010
- DOI:
- Bibcode:
- 2010ApPhL..97f3106L
- Keywords:
-
- alumina;
- bow-tie antennas;
- dielectric materials;
- gold;
- nanophotonics;
- nanostructured materials;
- optical films;
- plasmonics;
- red shift;
- refractive index;
- 42.79.Wc;
- 84.40.Ba;
- Optical coatings;
- Antennas: theory components and accessories