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 nanoimprnit, 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 at-ray 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. (C) 2009 Optical Society of America

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