Directional Scattering and Hydrogen Sensing by Bimetallic Pd-Au Nanoantennas
Journal article, 2012
Nanoplasmonic sensing is typically based on quantification of changes in optical extinction or scattering spectra. Here we explore the possibility of facile self-referenced hydrogen sensing based on angle-resolved spectroscopy. We found that heterodimers built from closely spaced gold and palladium nanodisks exhibit pronounced directional scattering, that is, for particular wavelengths, much more light is scattered toward the Au than toward the Pd particle in a dimer. The effect is due to optical phase shifts associated with the material asymmetry and therefore highly sensitive to changes in the permittivity of Pd induced by hydrogen loading. In a wider perspective, the results suggest that directional scattering from bimetallic antennas, and material asymmetry in general, may offer many new routes toward novel nanophotonic sensing schemes.
directional emission
palladium
surface-plasmons
storage materials
Nanoantenna
material asymmetry
nanostructures
scheme
hydrogen sensing
light-emission
plasmon resonance sensors
range
plasmonic sensing
interface
dipoles
Author
Timur Shegai
Chalmers, Applied Physics, Bionanophotonics
Peter Johansson
Chalmers, Applied Physics, Bionanophotonics
Christoph Langhammer
Chalmers, Applied Physics, Chemical Physics
Mikael Käll
Chalmers, Applied Physics, Bionanophotonics
Nano Letters
1530-6984 (ISSN) 1530-6992 (eISSN)
Vol. 12 5 2464-2469Areas of Advance
Nanoscience and Nanotechnology
Materials Science
Subject Categories
Other Engineering and Technologies
Infrastructure
Nanofabrication Laboratory
DOI
10.1021/nl300558h