Spectral dependence of single molecule fluorescence enhancement.

نویسندگان

  • Palash Bharadwaj
  • Lukas Novotny
چکیده

The fluorescence from a single molecule can be strongly enhanced near a metal nanoparticle acting as an optical antenna. We demonstrate the spectral tunability of this antenna effect and show that maximum enhancement is achieved when the emission frequency is red-shifted from the surface plasmon resonance of the particle. Our experimental results, using individual gold and silver particles excited at different laser-frequencies, are in good agreement with an analytical theory which predicts a different spectral dependence of the radiative and non-radiative decay rates.

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عنوان ژورنال:
  • Optics express

دوره 15 21  شماره 

صفحات  -

تاریخ انتشار 2007