Surface-Enhanced Raman and Fluorescence Spectroscopy with an All-Dielectric Metasurface

• DOI: 10.1021/acs.jpcc.8b03190
• Publication Date: 2018-08-03T22:11:19Z
• Authors: Silvia Romano; Gianluigi Zito; Stefano Managò; Giuseppe Calafiore; Erika Penzo; Stefano Cabrini; Anna Chiara De Luca; Vito Mocella
• Keywords: surface-enhanced Raman scattering; dielctric metasurface: Raman scattering; surface-enhanced fluorescence enhancement; fluorescence enhancement; Photonic crystal; 02 engineering and technology; 0210 nano-technology

Plasmonic substrates play a crucial role in the confinement and manipulation of localized electromagnetic fields at nanoscale. The large field enhancement metal/dielectric interfaces is widely exploited surface-enhanced fluorescence (SEF) Raman scattering (SERS) spectroscopies. Despite advantage near-field enhancement, unfortunately, metals, absorption optical frequencies induces local heating analyte fluid with possible damage biological material. In addition, SEF plasmonic substrates, spacer layers are necessary to minimize undesired quenching due nonradiative decay, which strongly depends on distance between molecules metallic substrates. Therefore, possibility managing surface states mimicking surface-plasmon resonances terms spatial localization, high-field intensity, dispersion characteristics, while avoiding losses great interest. However, dielectric nanoantennas can currently provide limited possibilities visible range frequencies. We present realization all-dielectric metasurfaces made nanostructured transparent silicon nitride supporting bound continuum (BICs). show that this special kind Fano be effectively used standard microscopy for practical applications. achieved concurrent enhancements ∼103 fold emission far-field intensities dispersed these metasurfaces. we demonstrate gain conventional SERS signals increased by more than one order magnitude resonant matching plasmon resonance BIC field. Our results find significant applications enhanced sensing, imaging, nonlinear processes.