Article

Nanoimprint fabrication of gold nanocones with approximately 10 nm tips for enhanced optical interactions.

Optoelectronics Research Centre, Tampere University of Technology, Department of Physics, Optics Laboratory, Tampere, Finland.
Optics Letters (Impact Factor: 3.18). 08/2009; 34(13):1979-81. DOI: 10.1364/OL.34.001979
Source: PubMed

ABSTRACT 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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