Mapping plasmonic near-field profiles and interferences by surface-enhanced Raman scattering.

ABSTRACT: Mapping near-field profiles and dynamics of surface plasmon polaritons is crucial for understanding their fundamental optical properties and designing miniaturized photonic devices. This requires a spatial resolution on the sub-wavelength scale because the effective polariton wavelength is shorter than free-space excitation wavelengths. Here by combining total internal reflection excitation with surface-enhanced Raman scattering imaging, we mapped at the sub-wavelength scale the spatial distribution of the dominant perpendicular component of surface plasmon fields in a metal nanoparticle-film system through spectrally selective and polarization-resolved excitation of the vertical gap mode. The lateral field-extension at the junction, which is determined by the gap-mode volume, is small eno

SUBMITTER: Du L 

PROVIDER: S-EPMC3810658 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature