Periodic metal resonator chains for Surface Enhanced Raman Scattering (SERS)

A periodic arrangement of chains of gold discs shows pronounced plasmonic grating resonances. These have a clear impact on the Surface Enhanced Raman Scattering (SERS)-signal from 4-methylbenzenethiol molecules which form self-assembled monolayers on the gold surface: Besides a clear polarisation dependence the SERS-spectra also exhibit a maximum when the excitation laser wavelength matches the plamonic grating resonance. These features are explained by a combined near and far field coupling of the individual plasmonic dipoles allowing the design of optimized nanostructures for effective SERS-substrates in the future.