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Title: Near-field Spectroscopy of Surface Plasmons in Flat Gold Nanoparticles

Abstract

We use near-field interference spectroscopy with a broadband femtosecond, white-light probe to study local surface plasmon resonances in flat gold nanoparticles (FGNPs). Depending on nanoparticle dimensions, local near-field extinction spectra exhibit none, one, or two resonances in the range of visible wavelengths (1.6-2.6 eV). The measured spectra can be accurately described in terms of interference between the field emitted by the probe aperture and the field reradiated by driven FGNP surface plasmon oscillations. The measured resonances are in good agreement with those predicted by calculations using discrete dipole approximation. We observe that the amplitudes of these resonances are dependent upon the spatial position of the near-field probe, which indicates the possibility of spatially selective excitation of specific plasmon modes.

Authors:
 [1];  [2];  [3];  [4];  [4];  [5]
  1. University of Massachusetts, Amherst
  2. ORNL
  3. Northwestern University, Evanston
  4. University of Oklahoma, Norman
  5. Los Alamos National Laboratory (LANL)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
931840
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Optics Letters; Journal Volume: 32; Journal Issue: 15
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; AMPLITUDES; APERTURES; DIMENSIONS; DIPOLES; EXCITATION; GOLD; OSCILLATIONS; PLASMONS; PROBES; SPECTRA; SPECTROSCOPY; WAVELENGTHS

Citation Formats

Achermann, Marc, Shuford, Kevin L, Schatz, George C., Dahanayaka, D H, Bumm, Lloyd A, and Klimov, Victor I. Near-field Spectroscopy of Surface Plasmons in Flat Gold Nanoparticles. United States: N. p., 2007. Web. doi:10.1364/OL.32.002254.
Achermann, Marc, Shuford, Kevin L, Schatz, George C., Dahanayaka, D H, Bumm, Lloyd A, & Klimov, Victor I. Near-field Spectroscopy of Surface Plasmons in Flat Gold Nanoparticles. United States. doi:10.1364/OL.32.002254.
Achermann, Marc, Shuford, Kevin L, Schatz, George C., Dahanayaka, D H, Bumm, Lloyd A, and Klimov, Victor I. Mon . "Near-field Spectroscopy of Surface Plasmons in Flat Gold Nanoparticles". United States. doi:10.1364/OL.32.002254.
@article{osti_931840,
title = {Near-field Spectroscopy of Surface Plasmons in Flat Gold Nanoparticles},
author = {Achermann, Marc and Shuford, Kevin L and Schatz, George C. and Dahanayaka, D H and Bumm, Lloyd A and Klimov, Victor I},
abstractNote = {We use near-field interference spectroscopy with a broadband femtosecond, white-light probe to study local surface plasmon resonances in flat gold nanoparticles (FGNPs). Depending on nanoparticle dimensions, local near-field extinction spectra exhibit none, one, or two resonances in the range of visible wavelengths (1.6-2.6 eV). The measured spectra can be accurately described in terms of interference between the field emitted by the probe aperture and the field reradiated by driven FGNP surface plasmon oscillations. The measured resonances are in good agreement with those predicted by calculations using discrete dipole approximation. We observe that the amplitudes of these resonances are dependent upon the spatial position of the near-field probe, which indicates the possibility of spatially selective excitation of specific plasmon modes.},
doi = {10.1364/OL.32.002254},
journal = {Optics Letters},
number = 15,
volume = 32,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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