Source nanoimprint fabrication of gold nanocones with ∼10 nm tips for enhanced optical interactions. Opt. Lett

Optoelectronics Research Centre, Tampere University of Technology, Department of Physics, Optics Laboratory, Tampere, Finland.
Optics Letters (Impact Factor: 3.29). 08/2009; 34(13):1979-81. DOI: 10.1364/OL.34.001979
Source: PubMed


We show that nanoimprint lithography combined with electron-beam evaporation provides a cost-efficient, rapid, and reproducible method to fabricate conical nanostructures with very sharp tips on flat surfaces in high volumes. We demonstrate the method by preparing a wafer-scale array of gold nanocones with an average tip radius of 5 nm. Strong local fields at the tips enhance the second-harmonic generation by over 2 orders of magnitude compared with a nonsharp reference.

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    • "Presumably, this phenomenon could have resulted from the localization of E field hotspot depending on the geometry of the nanostructures. For example, E field will be strongly localized at the sharp tip of the structures [27,28]. An intensive study is now underway to depict how the tip shape of nanostructures will affect the SPR phenomenon. "
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