Systematic study of the size and spacing dependence of Ag nanoparticle enhanced fluorescence using electron-beam lithography

We study the enhancement of fluorescence by Ag nanopillars on a semiconducting substrate in which the pillar size, shape, and spacing is varied systematically using electron-beam lithography. Local maxima in the enhancement versus lateral size, as large as a factor of ∼20 are observed, and vary both with the shape of the pillars and the wavelength of the excitation. We find that the size, shape, and spacing dependence is in qualitative agreement with a model based upon resonant coupling with particle plasmon polaritons. We also find increased enhancement for particle shapes producing high local electric fields.

[1]  R. Silbey,et al.  Molecular Fluorescence and Energy Transfer Near Interfaces , 2007 .

[2]  H. Szmacinski,et al.  Enhanced Fluorescence from Periodic Arrays of Silver Nanoparticles , 2005, Journal of Fluorescence.

[3]  U. Kreibig,et al.  Substrate effect on the optical response of silver nanoparticles , 2004 .

[4]  C. Mirkin,et al.  Controlling anisotropic nanoparticle growth through plasmon excitation , 2003, Nature.

[5]  David R. Smith,et al.  Plasmon resonances of silver nanowires with a nonregular cross section , 2001 .

[6]  J. Lakowicz.  Radiative decay engineering: biophysical and biomedical applications. , 2001, Analytical biochemistry.

[7]  C. Haynes,et al.  Nanosphere lithography: Tunable localized surface plasmon resonance spectra of silver nanoparticles , 2000 .

[8]  R. Dasari,et al.  Single Molecule Detection Using Surface-Enhanced Raman Scattering (SERS) , 1997 .

[9]  Steven R. Emory,et al.  Probing Single Molecules and Single Nanoparticles by Surface-Enhanced Raman Scattering , 1997, Science.

[10]  F. Aussenegg,et al.  Optical dichroism of lithographically designed silver nanoparticle films. , 1996, Optics letters.

[11]  S. Chin,et al.  Behaviour of D2 in an intense CO2 laser field , 1995 .

[12]  Michael Vollmer,et al.  Optical properties of metal clusters , 1995 .

[13]  F. Aussenegg,et al.  Novel aspects of fluorescence lifetime for molecules positioned close to metal surfaces , 1987 .

[14]  M. Moskovits.  Surface-enhanced spectroscopy , 1985 .

[15]  R. Fuchs,et al.  Theory of the optical properties of ionic crystal cubes , 1975 .

[16]  U. Kreibig,et al.  Surface plasma resonances in small spherical silver and gold particles , 1970 .