6533b829fe1ef96bd1289bac

RESEARCH PRODUCT

Influence of Fano resonance on SERS enhancement in Fano-plasmonic oligomers

Eero HulkkoArpan DuttaErik M. VartiainenJ. Jussi ToppariPetri KarvinenTarmo NuutinenMarkku KuittinenKhairul Alam

subject

Materials sciencePhysics::Optics02 engineering and technologyFano planeresonanssioptiset ominaisuudet01 natural sciencesLight scattering010309 opticsRhodamine 6Gchemistry.chemical_compoundsymbols.namesakeOptics0103 physical sciencessirontaPlasmonQuantitative Biology::Biomoleculesbusiness.industryScatteringfood and beveragesFano resonance021001 nanoscience & nanotechnologyAtomic and Molecular Physics and OpticsoligomeerichemistrysymbolsOptoelectronicsplasmonic oligomersvalokemia0210 nano-technologybusinessRaman spectroscopyExcitation

description

Plasmonic oligomers can provide profound Fano resonance in their scattering responses. The sub-radiant mode of Fano resonance can result in significant near-field enhancement due to its light trapping capability into the so-called hotspots. Appearance of these highly localized hotspots at the excitation and/or Stokes wavelengths of the analytes makes such oligomers promising SERS active substrates. In this work, we numerically and experimentally investigate optical properties of two disk-type gold oligomers, which have different strength and origin of Fano resonance. Raman analysis of rhodamine 6G and adenine with the presence of the fabricated oligomers clearly indicates that an increment in the strength of Fano resonance can improve the Raman enhancement of an oligomer significantly. Therefore, by suitable engineering of Fano lineshape, one can achieve efficient SERS active substrates with spatially localized hotspots. Peer reviewed

yearjournalcountryeditionlanguage
2019-11-06Optics Express
https://doi.org/10.1364/oe.27.030031