Effects of particle size and spacing on the optical properties of gold nanocrystals in alumina

Journal Article · Wed Jun 01 04:00:00 EDT 2005 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.1868052· OSTI ID:20711729

Juan, Wang; Lau, W M; Quan, Li ^[1]

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1. Department of Physics, The Chinese University of Hong Kong, Shatin, New Territory, Hong Kong (China)

Au-particle/Al{sub 2}O{sub 3}-matrix nanocomposite thin films with a narrow Au particle size distribution were fabricated by radio-frequency magnetron cosputtering. The films were characterized both chemically and structurally using x-ray photoelectron spectroscopy, x-ray diffraction, and transmission electron microscopy. The optical absorption of samples with various Au particle sizes and concentrations were measured using an ultraviolet/visible-spectrometer. Both the Au nanoparticle size and the Au concentration increase result in a redshift of the Au surface-plasmon resonance energy. The redshift due to the size effect is concluded as mainly originating from the size-dependent dielectric function of Au core electrons and a semiquantitative description of its size dependence is presented. The experimental result describing the concentration effect suggests a deviation from the conventional Maxwell-Garnett effective medium theory, which can be corrected by introducing the multipole effect based on the dipole-dipole interaction model.

• OSTI ID: 20711729
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 11 Vol. 97; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ABSORPTION
ALUMINIUM OXIDES
COMPOSITE MATERIALS
DEPOSITION
DIELECTRIC MATERIALS
DIPOLES
GOLD
NANOSTRUCTURES
OPTICAL PROPERTIES
PARTICLE SIZE
PARTICLES
RED SHIFT
RESONANCE
SPECTROMETERS
THIN FILMS
TRANSMISSION ELECTRON MICROSCOPY
ULTRAVIOLET SPECTRA
VISIBLE SPECTRA
X-RAY DIFFRACTION
X-RAY PHOTOELECTRON SPECTROSCOPY