2010 Volume 31 Issue 10 Pages 531-536
We present our recent studies related to an optical coupling between molecules and a localized enhanced electromagnetic field at well-defined metal nano-structure. Strong and anisotropic electromagnetic field, which is induced by localized surface plasmon at vicinity of metal surface under photo irradiation, was created by fabricating the optimized metal nano-structutre. Utilizing this system, surface-enhanced Raman scattering (SERS) studies were perfromed for molecules at the well-defined metal gap. First of all, we will demonstrate that obtained SERS spectra for two bipyridine molecules in solutions containing different concentrations originate from a few numbers of molecules at the active site of the metal dimer. Second, we introduce our current topic related to highly efficient SERS measurement for an isolated single-walled carbon nanotube (SWNT). We proved that the local electromagnetic field at the metal nano dimer allows us to probe localized optical response of a isolated SWNT at a single molecular level.
