Surface-enhanced Raman scattering efficiency of truncated tetrahedral Ag nanoparticle arrays mediated by electromagnetic couplings

Surface-enhanced Raman scattering (SERS) efficiency assessment of truncated tetrahedral Ag nanoparticle arrays with different vertical dimensions prepared by nanosphere lithography provides the experimental evidence of the electromagnetic (EM) coupling sensitivity to the nanoparticle heights. It is demonstrated that the EM couplings between the localized plasmon resonance of each particle and photonic modes of the particles array are solely accountable for the SERS enhancement of the rhodamine 6G molecules adsorbed on these substrates. Similar nanoparticle height dependent SERS enhancement trend is observed for the resonant excitation of the probe molecule.