Fabrication and characterization of plasmonic nanolens for applications in biophotonics

Abstract

This paper reports on the fabrication and characterization of a novel device for surface enhanced Raman scattering, fabricated using focused ion beam milling and electron beam induced deposition. The device exploits a photonic crystal cavity as an optical source to couple the incident laser with a metallic tapered nanolenses. The collected Raman measurements show that exploiting such approach is possible to overcome the difficulties related to scattering and diffraction phenomena occurring when visible laser illuminates nano-structures. A clear Raman scattering enhancement has been demonstrated for label-free detection of molecule in sub-wavelength regime. © 2008 Elsevier B.V. All rights reserved.