Detecting single-wall carbon nanotubes with surface-enhanced Raman scattering from metal-coated periodic structures

We report on surface-enhanced Raman scattering (SERS) from bundles of size-selected single-wall carbon nanotubes (SWCNTs) deposited on ordered arrays of silver- and gold-coated silica spheres. Selective enhancement of the Raman-active tangential and radial modes of SWCNTs is exhibited in backscattering at surface plasmon resonance conditions. Enhancement at plasmon wavelength and sub-wavelength is shown for various periodic pitches of the substrates used.