Substrate-based platform for boosting the surface-enhanced Raman of plasmonic nanoparticles.

Metal nanoparticles allow for surface-enhanced Raman scattering (SERS), with applications including spectroscopy and highly-multiplexed biolabels. Despite advances in nanoparticles design nanoparticles, the SERS from these systems is still weak when compared with randomly roughened substrates, and this limits their efficacy for many applications. Here, we coherently boost the SERS signal of colloidally-synthesized silver nano-prisms over 50 × by using multilayer substrates. Theoretical calculations verify the enhancement, and uncover the near-field response. This points the way toward a versatile platform for greater SERS enhancement from nanoparticles.