Single Particle Spectroscopy Study of Metal-Film-Induced Tuning of Silver Nanoparticle Plasmon Resonances

    Authors

    M. Hu; A. Ghoshal; M. Marquez;P. G. Kik

    Comments

    Authors: contact us about adding a copy of your work at STARS@ucf.edu

    Abbreviated Journal Title

    J. Phys. Chem. C

    Keywords

    OPTICAL-ABSORPTION; REFRACTIVE-INDEX; SMALL SPHERE; SUBSTRATE; SURFACE; ARRAYS; SCATTERING; SYSTEM; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, ; Multidisciplinary

    Abstract

    We present an experimental study of the tunability of the silver nanoparticle localized plasmon resonance in close proximity to a gold film. Broad-band tuning of the silver particle plasmon resonance from blue wavelengths into the near-IR region can be achieved due to strong electromagnetic coupling between the nanoparticle and the metal film. When the thickness of a thin silica spacer layer between the metal nanoparticle and the metal film is altered, the resonance frequency shifts. Single particle spectroscopy of over 250 isolated silver nanoparticles revealed evidence for the excitation of both horizontal and vertical plasmon modes. Distinct resonance features observed in the scattering spectra were assigned to specific modes based on a dipole-dipole interaction model. The experimental results suggest that low-loss silver nanoparticles can be used in surface-enhanced spectroscopy studies throughout the entire visible spectrum. The use of frequency-tuned spherical metal nanoparticles on solid substrates could lead to thermally stable substrates for plasmon-enhanced sensing applications, including surface-enhanced Raman scattering and refractive index based biodetection methods.

    Journal Title

    Journal of Physical Chemistry C

    Volume

    114

    Issue/Number

    16

    Publication Date

    1-1-2010

    Document Type

    Article

    Language

    English

    First Page

    7509

    Last Page

    7514

    WOS Identifier

    WOS:000276889300044

    ISSN

    1932-7447

    Share

    COinS