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1.
J.C. Pivin M. Sendova-Vassileva M. Nikolaeva D. Dimova-Malinovska A. Martucci 《Applied Physics A: Materials Science & Processing》2002,75(3):401-410
Three methods based on ion-beam irradiation were used to fabricate Ag and Au colloids in silica and alumina. Their surface-plasmon
resonance in the visible was characterised by transmittance measurements and interpreted on the basis of transmission electron
microscope observations. Despite their bimodal size distribution, particles formed by ion-beam mixing of sandwich layers exhibit
much narrower resonances than those obtained by ion implantation. This unusual effect of an inhomogeneity in cluster size
is ascribed to the spatial organisation of these clusters. Irradiation of supersaturated solid solutions at much lower ion
fluences produces colloids with more uniform size and spatial distributions, and equally strong resonances.
Received: 17 March 2001 / Accepted: 31 July 2001 / Published online: 11 February 2002 相似文献
2.
S.M. Huang M.H. Hong B. Lukiyanchuk T.C. Chong 《Applied Physics A: Materials Science & Processing》2003,77(2):293-296
Nanostructures on metal film surfaces have been written directly using a pulsed ultraviolet laser. The optical near-field
effects of the laser were investigated. Spherical silica particles (500–1000 nm in diameter) were placed on metal films. After
laser illumination with a single laser shot, nanoholes were obtained at the original position of the particles. The mechanism
for the formation of the nanostructure patterns was investigated and found to be the near-field optical resonance effect induced
by the particles on the surface. The size of the nanohole was studied as a function of laser fluence and silica particle size.
The experimental results show a good agreement with those of the relevant theoretical calculations of the near-field light
intensity distribution. The method of particle-enhanced laser irradiation allows the study of field enhancement effects as
well as its potentialapplications for nanolithography.
Received: 10 December 2002 / Accepted: 20 January 2003 / Published online: 28 May 2003
RID="*"
ID="*"Corresponding author. Fax: +65-777/1349, E-mail: HUANG_Sumei@dsi.a-star.edu.sg 相似文献
3.
Feng Ren Xiang Heng Xiao Guang Xu Cai Jian Bo Wang Chang Zhong Jiang 《Applied Physics A: Materials Science & Processing》2009,96(2):317-325
In this paper, we summarize our recent results of study on how to engineer the embedded metal nanoparticles in silica by ion
implantation and ion irradiation technologies, including controlling the size, distribution and morphology of nanoparticles.
The optical properties of the tailored nanoparticle composites are studied. Thermal annealing, electron beam irradiation,
and chemical erosion are used to study the stability of these embedded nanoparticles by ex situ or in situ transmission electron
microscopy observation. 相似文献
4.
Th. Cabioc'h S. Camelio L. Henrard Ph. Lambin 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,18(3):535-540
Concentric-shell fullerenes, also called carbon onions, produced by carbon ion implantation into silver thin films, and subsequently
deposited on a silica substrate, were studied by optical transmission spectroscopy in the wavelength range 0.2 - 1.2 μm. In
this interval, the strongest absorption is due to the π-plasmon of sp2-like carbon. The position of the plasmon absorption band clearly evolved from 265 nm at low fluence to 230 nm at high implantation
fluences. A simulation of the optical spectra based on dielectric models of the concentric-shell fullerenes layer allowed
us to identify the first peak as due to disordered graphite and the latter to the carbon onions. The concentration of residual
graphite and the filling fraction of the carbon onions produced at high fluences could be estimated by fitting the optical
spectra with computed transmittance curves.
Received 13 July 2000 相似文献
5.
Kögler R. Eichhorn F. Kaschny J.R. Mücklich A. Reuther H. Skorupa W. Serre C. Perez-Rodriguez A. 《Applied Physics A: Materials Science & Processing》2003,76(5):827-835
Nanometer-sized SiC precipitates were synthesized in situ in Si by simultaneous implantation of two ion beams of C+ and Si+ ions. The results of simultaneous dual-beam implantation are compared with those of sequential dual-beam ion implantation
and of single-beam C+ ion implantation. Remarkable differences are observed regarding the content and the crystal quality of SiC precipitates as
well as the defect structure of the Si substrate. The SiC precipitation during dual-beam synthesis is found to depend on the
ion energy of the second beam and on the implantation mode, simultaneous or sequential. For suitable implantation conditions,
simultaneous dual-beam synthesis can improve the in situ SiC formation in comparison to the single-beam synthesis. A higher
density of SiC precipitates with better crystal quality was observed, whereas their size was not changed. The second ion beam
enables a shift in the dynamic equilibrium of constructive and destructive processes for SiC formation. A model is proposed
assuming that SiC precipitation preferentially proceeds in regions with vacancy defects. The implantation process itself creates
vacancy-dominated and also interstitial-dominated regions. The balance of the local point-defect composition is shifted under
the second ion beam. In this way, the conditions for SiC precipitation can be modified.
Received: 18 February 2002 / Accepted: 17 May 2002 / Published online: 17 December 2002
RID="*"
ID="*"Corresponding author. Fax: +49-351/260-3411, E-mail: koegler@fz-rossendorf.de 相似文献
6.
Silver colloids in aqueous solution were studied by different scanning microscopy techniques and UV/VIS spectroscopy. The
silver colloids were produced either by chemical reduction or by nanosecond laser ablation from a solid silver foil in water.
Variation of laser power and ablation time leads to solutions of metal clusters of different sizes in water. We characterized
the electronic absorption of the clusters by UV/VIS spectroscopy. STM (scanning tunneling microscope) imaging of the metal
colloids shows atomic resolution of rod- or tenon-like silver clusters up to 10-nm length formed by laser ablation. Our scanning
electron microscope measurements, however, show that much larger silver colloids up to 5-μm length are also formed, which
are not visible in the STM due to their roughness. We correlate them with the long-wavelength tail of the multimodal UV/VIS
spectrum. The silver colloids obtained by chemical reduction are generally larger and their electronic spectra are red-shifted
compared to the laser-ablated clusters. Irradiation of the colloid solution with nanosecond laser pulses of appropriate fluence
at 532 nm and 355 nm initially reduced the colloid size. Longer irradiation at 355 nm, however, leads to the formation of
larger colloids again. There seems to be a critical lower particle size, where silver clusters in aqueous solution become
unstable and start to coagulate.
Received: 24 June 2002 / Revised version: 25 July 2002 / Published online: 25 October 2002
RID="*"
ID="*"This work is part of the thesis of H. M?ltgen
RID="**"
ID="**"Corresponding author. Fax: +49-211/811-5195, E-mail: kleinermanns@uni-duesseldorf.de 相似文献
7.
M. Dubiel R. Schneider H. Hofmeister K.-D. Schicke J. C. Pivin 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,43(1-3):291-294
The formation of argentic clusters and very small Ag
nanoparticles of 0.5 to 2 nm size in commercial soda-lime glass silver-doped
by Ag/Na ion exchange in a mixed nitrate melt has been studied by electron
microscopy and EXAFS. Particles formation was induced already during the ion
exchange procedure, or by subsequent ion irradiation with 1.5 MeV He+
or 3 MeV Au+. The presence of nanoparticles was also macroscopically
revealed by their surface plasmon resonance. The structural characterization
indicates that specific configurations of silver oxide-like structures,
so-called argentic clusters, are involved in the initial stage of
nanoparticles formation. 相似文献
8.
M. Dubiel H. Hofmeister G. L. Tan K.-D. Schicke E. Wendler 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,24(1-3):361-364
Silver particles in soda-lime glass, less than 10 nm in
size, were prepared by ion implantation. The implantation dose
was in the range of 0.5 to 2×1016 Ag
ions/cm2 and the beam current density
was varied from 0.5 to 2A/cm2. Here,
the beam current density strongly influences ion diffusion and
particle precipitation as well as compressive stress generation
around the particles due to thermal effects resulting from the
deceleration of silver ions. Stress relaxation can be achieved
by increased dose rates or thermal processing at elevated
temperatures. Based on RBS and HREM results, a possible route to
homogeneous distribution of Ag nanoparticles within the glass is
discussed with respect to their interesting optical properties. 相似文献
9.
M.N. Huda A.K. Ray 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,22(2):217-227
The formalisms of many body perturbation theory and coupled cluster theory have been used to study the electronic and geometric
structures of neutral, cationic, and anionic small silver clusters. Hay-Wadt relativistic effective core potentials replacing
the twenty-eight core electrons and a Gaussian basis set have been used. Topologically different clusters and clusters belonging
to different symmetry groups have been identified and studied in detail. Full geometry optimizations have been carried out
at four different correlated levels of theories. Ionization potentials, electron affinities, and fragmentation energies of
the optimized clusters have been compared with other experimental and theoretical results available in the literature. No
convergence problems are encountered at the various levels of correlated theories. This is noteworthy since it has been claimed
in the literature that for d elements the MP series does not converge very well.
Received 16 April 2002 / Received in final form 12 September 2002 Published online 21 January 2003
RID="a"
ID="a"e-mail: akr@uta.edu 相似文献
10.
E. Barborini I. N. Kholmanov A. M. Conti P. Piseri S. Vinati P. Milani C. Ducati 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,24(1-3):277-282
Nanostructured titanium dioxide films have been deposited
by supersonic cluster beam deposition (CBD). Nanoparticles are
produced by a pulsed microplasma cluster source (PMCS) and
selected by aerodynamic separation effects. The as-deposited
film is a complex mixture where amorphous material coexists, at
the nanoscale, with anatase and rutile crystal phases. The
nanocrystalline fraction of the film is characterized by crystal
size ranging from 100 nm to less than 5 nm. We have
characterized the film structure by transmission electron
microscopy, Raman spectromicroscopy, X-ray diffraction, and
UV-visible spectroscopy showing that correlations exist between
cluster size and film properties. In particular if very small
clusters are deposited, the film shows a predominant rutile
phase whereas larger clusters form films with mainly anatase
structure. Our observations suggest that phonon confinement
effects are responsible for a significant shift and broadening
observed for the Raman peaks. In addition, optical gap tuning is
provided by mass selection: large clusters assembling generates
a film with 3.22 eV optical gap, while smallest clusters 3.52
eV. 相似文献
11.
Irradiation-assisted processing, i.e. ion, electron and laser irradiation, have been applied to fabricate metal/glass nanocomposites. The particle configurations are studied by transmission electron microscopy to get some insight into the rather complex formation mechanisms. Special attention is given to spheroidally shaped particles surrounded by smaller secondary particles observed upon ion beam mixing of silica/silver/silica layer compounds as well as irradiating femtosecond laser pulses on sodium silicate glass containing spherical silver particles. Another unique type of structure are cavities observed in silver particles formed by high fluence ion implantation into silica as well as upon laser pulse irradiation of silver particles in glass. The experimental findings are discussed in terms of irradiation-induced defect formation and radiation-enhanced diffusion. 相似文献
12.
R. Lazzari I. Simonsen D. Bedeaux J. Vlieger J. Jupille 《The European Physical Journal B - Condensed Matter and Complex Systems》2001,24(2):267-284
The light scattering by three-dimensional clusters supported by a substrate is modelled by representing clusters by truncated
spheroids whose polarizability is calculated via a multipolar development of the potential in the quasi-static limit. The determination of the mean island radius, density
and aspect ratio from the optical response is examined. The strong influence of both the particle-substrate interaction and
the particle shape on the optical behaviour is demonstrated, showing the limits of effective medium and dipolar theories.
The Surface Differential Reflectance spectra of silver on MgO(100) and titanium or aluminium on α-Al2O3(0001) surfaces have then been modelled by using the above model, illustrating the capability of optical means to deal with
various metals, including those belonging to transition series. In all cases, it is highlighted that the aspect ratio is central
in modelling the optical response of supported particles.
Received 5 June 2000 and Received in final form 31 July 2001 相似文献
13.
P.-G. Reinhard E. Suraud 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,21(3):315-322
We use time-dependent density functional theory coupled to molecular dynamics for ionic motion to compute the spectra of ionic
vibrations in small Na clusters. Comparison with results from the distance dependent tight-binding approach shows good agreement
between these two very different methods. We discuss the evolution of the spectra with cluster size and charge and the impact
of ionic vibrations on the optical response.
Received 23 July 2001 / Received in final form 5 July 2002 Published online 8 October 2002
RID="a"
ID="a"e-mail: suraud@irsamc.ups-tlse.fr 相似文献
14.
J. Beauvais P. Galarneau R. A. Lessard E. J. Knystautas 《Applied Physics A: Materials Science & Processing》1990,51(6):515-519
Helium implantations were realized in polycrystalline tellurium thin films. Discontinuities in the dependence of the relative threshold writing energy with both implanted ion dose and ion beam energy are observed. Correlations between the optical recording properties and the optical loss of the thin films suggest that the intrinsic threshold writting energy of the films is influenced by the implantation process. 相似文献
15.
K. Manninen M. Manninen 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,20(2):243-249
Ground state geometries of small hard sphere clusters were studied using two different type of contact interaction, a pair-potential
and a many-atom interaction. Monte Carlo method in an FCC lattice with all possible (111) stacking faults was used to obtain
the minimum energy geometries for clusters up to 59 atoms. Due to the surface energy, FCC packing is generally favoured as
opposite to the HCP structure. However, in most cluster sizes the ground state obtained with the many-atom interaction has
one or more stacking faults. The most symmetric geometry is usually not the ground state. Clusters with 59 and 100 atoms were
studied due the possibility of a high symmetry cluster with stacking faults in all four directions. The size dependence of
the total energy has similarities with that of the average moment of inertia.
Received 6 February 2002 / Received in final form 11 April 2002 Published online 19 July 2002 相似文献
16.
A. Brioude F. Lequevre J. Mugnier C. Bovier J. Dumas J.C. Plenet 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,26(1):115-119
Very thin ZrO
2
films (few nanometers) have been prepared by sol-gel process. These films were deposited onto a stack of a thin silver layer
evaporated on a glass substrate for Surface Plasmons Resonance (SPR) experiments. The first aim of this work is to study the
high densification of the sol-gel films followed by the refractive index and thickness accurate measurements at each step
of the annealing procedure, using an optical set-up based on SPR. Secondly, SPR excitation coupled with micro-Raman experiment
has also been performed to determine the thin films structure depending on layer thickness. Finally, Conventional Transmission
Electron Microscopy (CTEM) and High Resolution (HRTEM) studies have been conducted to check and complete Raman spectroscopy
results. A discussion compares the optical results and the Transmission Electron Microscopy observations and shows that ultra
thin layers structure is strongly depends on films thickness.
Received 14 May 2001 and Received in final form 2 January 2002 相似文献
17.
Zhi Ping Wang Xi Xia Liang 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,33(3):265-271
Rayleigh-Schr?dinger perturbation theory and an improved Wigner-Brillouin perturbation theory has been used to study the cyclotron
resonance of the polarons in ternary mixed crystals in the zero-temperature limit. The interaction between an electron and
two branches of longitudinal optical phonon modes is taken into account in the framework of the random-element-isodisplacement
model. The numerical results for several ternary mixed crystals show that the polaronic cyclotron energy and mass split successively
twice related to the higher and lower branches of longitudinal optical phonon modes of ternary mixed crystals. A non-linear
dependence of the polaronic cyclotron energy and mass on the composition x is found.
Received 19 March 2002 / Received in final form 21 March 2003 Published online 20 June 2003
RID="a"
ID="a"e-mail: xxliang@imu.edu.cn 相似文献
18.
Vicari L 《The European physical journal. E, Soft matter》2002,9(4):335-340
We present a new pump probe laser beams configuration for the nonlinear optical characterization of microemulsions. We detect
the variation of the on-axis optical intensity of the probe beam as generated by the concentration profile induced in an optically
thin film of microemulsion by the pump beam. A mathematical model has been introduced to describe the phenomenon. The technique
allows the determination of both Kerr-like optical nonlinearity and time constants and, therefore, it gives information both
on cluster dimension and their shape. We discuss its application to WAD (water/AOT/decane, where AOT denotes sodium-bis-di-ethyl-sulfosuccinate)
with the application of a strong electric field of optical source. Comparison between theoretical predictions and experimental
results confirms the presence of giant optical nonlinearity in the absence of turbidity divergence. Chainlike shape of clusters,
of the kind already reported with the application of strong electric field, could justify this result.
Received 26 October 2002
RID="a"
ID="a"e-mail: vicari@na.infn.it 相似文献
19.
W. Vervisch C. Mottet J. Goniakowski 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,24(1-3):311-314
Morphology and atomic structure of supported Pd clusters
on MgO(100) substrate are investigated theoretically using a
mixed approach: a semi-empirical potential for the metal bonding
within the cluster and a potential fitted to
ab initio calculations for
the metal-oxide interaction. We find that the clusters adopt a
truncated pyramidal morphology in agreement with experimental
results. The detailed study of the epitaxial relation as a
function of cluster size shows the existence of a critical size
around 3 nm where elastic strain due to the misfit between the
substrate and the deposit is released by the introduction of
interfacial dislocations. 相似文献
20.
R.-P. Methling V. Senz E.-D. Klinkenberg Th. Diederich J. Tiggesbäumker G. Holzhüter J. Bansmann K.H. Meiwes-Broer 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,16(1):173-176
We have investigated the magnetic properties of mass-selected iron clusters using the Magneto-Optical Kerr effect (MOKE) in
longitudinal geometry. For the production of these clusters, a newly developed continuous arc cluster ion source (ACIS) was
applied. The source is based on cathodic arc erosion in inert gas environment and subsequent expansion into high vacuum. Its
intensity and stability allows mass selection within a wide size range. The source efficiency is demonstrated in deposition
experiments and transmission electron microscopy. For mass-selected iron particles deposited into a silver matrix we could
observe a change in the magnetic behaviour from ferromagnetism to superparamagnetism around a size of 10 nm at room temperature.
Received 1st December 2000 相似文献