Plasmonic Tip Internally Excited via Cylindrical Vector Beam for Surface Enhanced Raman Spectroscopy

Abstract

Plasmonic tips i.e. silver-film coated fiber tip and silver-nanoparticles coated fiber tip are presented to have the ability of significantly enhancing Raman intensity under the internal illumination of cylindrical vector beams i.e. radial vector beam and azimuthal vector beam respectively. In the case of radial vector beam illumination, the Raman intensity of malachite green is 15 times as strong as that illuminated via the linear polarization beam. In the case of azimuthal vector beam illumination, the magnification of Raman intensity can reach ~8.