A modified Mie scattering theory was used to calculate the enhancement of electromagnetic (EM) field between gold nanospheres. The simulation result showed that the density of EM-energy in the space between neighboring nanospheres increases drastically as the interparticle space decreases. Simulated absorption-spectra also showed a peak-shifting from the visible to the infrared region when decreasing the nanosphere spacing. We used our previous experiment to verify the analytical results; the experiment was conducted by using a photodeformable microshell, which was coated with gold nanospheres. Made of photoshrinkable azobenzene polyelectrolytes, the microshells supported the gold nanospheres and gave the tunability of the interparticle spacing among the nanospheres. Upon irradiation of ultraviolet light, the microshells shrank and reduced the interparticle space. The absorption-spectra of the gradually shrinking microshells showed significant changes; a peak-broadening from the visible to the near-infrared region and a drastically enhanced water-absorption were observed in the experimental spectra. The experimental results confirmed the analytical analysis based on the modified scattering theory.

Issue Section:
Micro/Nanoscale Heat Transfer—Part I
Keywords:
gold, infrared spectra, Mie scattering, nanostructured materials, visible spectra
Topics:
Absorption, Electromagnetic fields, Electromagnetic scattering, Irradiation (Radiation exposure), Particulate matter, Radiation scattering, Scattering (Physics), Shrinkage (Materials), Spectra (Spectroscopy), Ultraviolet radiation, Water absorption, Water, Scattering theory, Simulation results, Density, Absorption spectra, Waves
1.
Mie
,
G.
, 1908, “
Beiträge zur Optik trüber Medien speziell kolloidaler Metallösungen
,”
Ann. Phys.
0003-3804,
25
, pp.
376
–
445
.
2.
Craig
,
F. B.
, and
Donld
,
R. H.
, 1983,
Absorption and Scattering of Light by Small Particles
,
Wiley
,
Canada
, pp.
83
–
129
.
3.
Shvalagin
,
V. V.
,
Stroyuk
,
A. L.
, and
Kuchmii
,
S. Y.
, 2007, “
Photochemical Synthesis of ZnO/Ag Nanocomposites
,”
J. Nanopart. Res.
,
9
(
3
), pp.
427
–
440
. 1388-0764
Crossref
Search ADS
 
4.
Vandenbem
,
C.
, and
Vigneron
,
J. P.
, 2005, “
Mie Resonances of Dielectric Spheres in Face-Centered Cubic Photonic Crystals
,”
J. Opt. Soc. Am. A
0740-3232,
22
(
6
), pp.
1042
–
1047
.
Crossref
Search ADS
 
5.
Banerjee
,
M.
,
Datta
,
S. K.
, and
Saha
,
H.
, 2005, “
Enhanced Optical Absorption in a Thin Silicon Layer With Nanovoids
,”
Nanotechnology
0957-4484,
16
(
9
), pp.
1542
–
1548
.
Crossref
Search ADS
 
6.
Mackowski
,
D. W.
, 1991, “
Analysis of Radiative Scattering for Multiple Sphere Configurations
,”
Proc. R. Soc. London, Ser. A
1364-5021,
433
, pp.
599
–
614
.
Crossref
Search ADS
 
7.
Jackson
,
J. D.
, 1999,
Classical Electrodynamics
, 3rd ed.,
Wiley
,
New York
, pp.
352
–
356
.
8.
Chern
,
R.
,
Liu
,
X.
, and
Chang
,
C.
, 2007, “
Particle Plasmons of Metal Nanospheres: Application of Multiple Scattering Approach
,”
Phys. Rev. E
1063-651X,
76
, p.
016609
.
Crossref
Search ADS
 
9.
Segelstein
,
D.
, 1981, “
The Complex Refractive Index of Water
,” MS thesis, University of Missouri, Kansas City, MO.
10.
Weaver
,
J. H.
, and
Frederikse
,
H. P. R.
, 2001,
Optical Properties of Selected Elements
, 82nd ed.,
CRC
,
Boca Raton, FL
.
11.
Kreibig
,
U.
, and
Vollmer
,
M.
, 1995,
Optical Properties of Metal Clusters
,
Springer
,
New York
.
12.
Kawata
,
S.
, 2001,
Near-Field Optics and Surface Plasmon Polaritons
,
Springer
,
New York
.
13.
Johnson
,
P. B.
, and
Christy
,
R. W.
, 1972, “
Optical Constants of the Noble Metals
,”
Phys. Rev. B
0556-2805,
6
, pp.
4370
–
4379
.
Crossref
Search ADS
 
14.
Kittel
,
C.
, 1971,
Introduction to Solid State Physics
, 4th ed.,
Wiley
,
Canada
, p.
248
.
15.
Rechberger
,
W.
,
Hohenau
,
A.
,
Leitner
,
A.
,
Krenn
,
J. R.
,
Lamprecht
,
B.
, and
Aussenegg
,
F. R.
, 2003, “
Optical Properties of Two Interacting Gold Nanoparticles
,”
Opt. Commun.
0030-4018,
220
, pp.
137
–
141
.
Crossref
Search ADS
 
16.
Feringa
,
B. L.
, 2001,
Molecular Switches
,
Wiley-VCH
,
Weinheim
, p.
399
.
17.
Han
,
L.
,
Tang
,
T.
, and
Chen
,
S.
, 2006, “
Tuning the Absorptions of Au Nanospheres on a Microshell by Photo-Deformation
,”
Nanotechnology
0957-4484,
17
, pp.
4600
–
4605
.
Crossref
Search ADS
PubMed
 
18.
Palmer
,
K. F.
, and
Williams
,
D.
, 1974, “
Optical Properties of Water in the Near Infrared
,”
J. Opt. Soc. Am.
0030-3941,
64
(
8
), pp.
1107
–
1110
.
Crossref
Search ADS
 
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