Last modified: 2011-12-14
Abstract
A sensitive molecule detector is realized by strong plasmon-vibration coupling effects between functional groups and plasmonic meta-surfaces. Various plasmonic meta-surfaces are fabricated by a series of asymmetric spilt ring resonators (ASRRs) arrays that inherent strong localized plasmonic infrared field to enhance the spectral signature of molecular vibrations. The fabricated ASRRs structures exhibit multiple reflectance peaks, whose spectral positions are designable by our standing-wave plasmonic resonance model, providing a design rule for this multi-mode plasmon-vibration sensor (MPVS). By employing unpolarized light, our experiment results perform significant plasmon-vibration resonances in the ultra wide band between subradiant mode and superradiant mode resonances. We further manifest that the superradiant modes possess greater sensitivity associated with stronger localized electromagnetic field than the subradiant mode. These unique merits enable the ASRR-based sensor a multi-functional biosensor and a potential label-free imaging devices