Surface-enhanced Rama spectroscopy in Silver nanowire-based transparent films VS Gold Engineered Metamaterials

In this paper we compare a bottom-up approach and a top-down technique to realize efficient SERS substrates for plasmonic "label-free" nanobiosensors. We demonstrate that SERS enhancement factors of the order of ~ 107 can be reproducibly obtained using Au photonic quasi crystals arrays of nano-pillars