Journal
PLASMONICS
Volume 9, Issue 3, Pages 581-593Publisher
SPRINGER
DOI: 10.1007/s11468-014-9669-4
Keywords
Gold nanorods; Localized surface plasmon resonance; SERS; Nonlinear optics; Push-pull molecule
Funding
- Italian Ministry for Education, University and Research (MIUR) through the PRIN
- University of Padova through the PLATFORM project PLAsmonic nano-Textured materials and architectures FOR enhanced Molecular Sensing
- Italian Interuniversity Consortium for Science and Technology of Materials (INSTM) through the PROMO Programme
Ask authors/readers for more resources
The amplification of Raman signals of the heteroaromatic cation 1-(N-methylpyrid-4-yl)-2-(N-methylpyrrol-2-yl)ethylene (PEP+)) bound to Au nanorods (NRs) was investigated at different excitation wavelengths to study the effect of the laser resonance with the absorption band of the PEP+ moiety and with the two plasmon oscillation modes of the NR. Two different PEP+ derivatives, differing in the length of the alkyl chain bearing the anchoring group, were used as target molecules. Raman spectra obtained exciting at 514 or at 785 nm (i.e., exciting the transverse or the longitudinal plasmon band) present a higher intensity than that at 488 nm suggesting a higher Raman amplification when the laser excitation wavelength is resonant with one of the two plasmon modes. Moreover, considering results of Discrete Dipole Approximation (DDA) calculations of the local field generated at the NR surface when either the transverse or the longitudinal plasmon modes are excited, we deduced that the resonance condition of the 514-nm laser excitation with the absorption band of the dye strongly contributes to the amplification of the Raman signal.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available