Properties of resonant modal-plasmonic multiparametric biosensors

We initiate a fundamental study of modal-plasmonic interactions in nanostructured resonance elements with the aim to develop new hybrid multiparametric sensors. The proposed hybrid sensor operates under guided-mode resonance (GMR) and surface-plasmon resonance (SPR) in unison. Numerical simulations of gold-integrated periodic resonant films show effective spectral conversions due to interplay between these mechanisms. In some cases, we find enhancements in sensitivity and attendant reduced resonance linewidths improving sensor resolution. Initial experimental results incorporating modal-plasmonic interactions in a resonant system containing a dielectric grating on a thin gold film agree qualitatively with theory. The research is important as the SPR and GMR concepts are independently the basis for commercial sensor systems with major economic impact.