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Graphene induced tunability of the surface plasmon resonance

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 Added by Hyunsoo Yang
 Publication date 2012
  fields Physics
and research's language is English




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Tunability of the surface plasmon resonance wavelength is demonstrated by varying the thickness of Al2O3 spacer layer inserted between the graphene and nanoparticles. By varying the spacer layer thickness from 0.3 to 1.8 nm, the resonance wavelength is shifted from 583 to 566 nm. The shift is due to a change in the electromagnetic field coupling strength between the localized surface plasmons excited in the gold nanoparticles and a single layer graphene film. In contrast, when the graphene film is absent from the system, no noticeable shift in the resonance wavelength is observed upon varying the spacer thickness.



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