Plasmonic coupling of SiO2-Ag “post-cap” nanostructures and silver film for surface-enhanced Raman scattering

摘要

We demonstrate a surface-enhanced Raman scattering (SERS) substrate consisting of SiO2-Ag “post-cap” nanostructures with an underlying silver film. Optimized coupling between freestanding Ag caps and the underlying silver film results in a maximum enhancement factor of 2.38×109.