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Search for "nanospheres" in Full Text gives 135 result(s) in Beilstein Journal of Nanotechnology.

The Kirkendall effect and nanoscience: hollow nanospheres and nanotubes

  • Abdel-Aziz El Mel,
  • Ryusuke Nakamura and
  • Carla Bittencourt

Beilstein J. Nanotechnol. 2015, 6, 1348–1361, doi:10.3762/bjnano.6.139

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  • the conversion chemistry of nanostructures from solid to hollow has reached a very advanced maturity, there is still much to be discovered and learned on this effect. Here, the recent progress on the use of the Kirkendall effect to synthesize hollow nanospheres and nanotubes is reviewed with a special
  • emphasis on the fundamental mechanisms occurring during such a conversion process. The discussion includes the oxidation of metal nanostructures (i.e., nanospheres and nanowires), which is an important process involving the Kirkendall effect. For nanospheres, the symmetrical and the asymmetrical mechanisms
  • conclude with a summary, where the prospective future direction of this research field is discussed. Keywords: hollow nanospheres; Kirkendall effect; metals; nanotubes; oxides; Review Introduction In the years following the discovery of the diffusion of gold in solid lead by Roberts-Austen in 1896 [1][2
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Published 18 Jun 2015

Influence of the shape and surface oxidation in the magnetization reversal of thin iron nanowires grown by focused electron beam induced deposition

  • Luis A. Rodríguez,
  • Lorenz Deen,
  • Rosa Córdoba,
  • César Magén,
  • Etienne Snoeck,
  • Bert Koopmans and
  • José M. De Teresa

Beilstein J. Nanotechnol. 2015, 6, 1319–1331, doi:10.3762/bjnano.6.136

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  • magnetic structures [19], the growth of three-dimensional nanowires [20][21] and the fabrication of nanospheres on scanning probe tips [22][23]. One of the crucial parameters to be controlled in such magnetic nanostructures grown by FEBID is the coercive field, HC, which corresponds to the magnetic field
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Published 15 Jun 2015

PLGA nanoparticles as a platform for vitamin D-based cancer therapy

  • Maria J. Ramalho,
  • Joana A. Loureiro,
  • Bárbara Gomes,
  • Manuela F. Frasco,
  • Manuel A. N. Coelho and
  • M. Carmo Pereira

Beilstein J. Nanotechnol. 2015, 6, 1306–1318, doi:10.3762/bjnano.6.135

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  • significant. Acronyms TEM images of (a) unloaded PLGA nanospheres, scale bar: 200 nm; and (b) loaded PLGA nanospheres, scale bar: 500 nm. The white arrow indicates the pluronic layer surrounding the PLGA NP. In vitro release profile of calcitriol from PLGA NPs in PBS (0.01 M, pH 7.4) at 37 °C. The data is
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Published 12 Jun 2015

Experimental determination of the light-trapping-induced absorption enhancement factor in DSSC photoanodes

  • Serena Gagliardi and
  • Mauro Falconieri

Beilstein J. Nanotechnol. 2015, 6, 886–892, doi:10.3762/bjnano.6.91

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  • photoanode with the light absorbed by the dye without the mesoporous titania structure. In order to gain more insight from this result, the fraction of light absorbed in the photoanode (on the basis of the dye loading capacity of the titania nanospheres) was also calculated by an optical model for the two
  • titania nanospheres was also calculated using a simplified, purely optical model in the two extreme cases of no or maximum light trapping [14]. The corresponding short-circuit photocurrent density under AM1.5 illumination of an ideal DSSC was then calculated for the two limiting cases above and compared
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Published 02 Apr 2015

Silica micro/nanospheres for theranostics: from bimodal MRI and fluorescent imaging probes to cancer therapy

  • Shanka Walia and
  • Amitabha Acharya

Beilstein J. Nanotechnol. 2015, 6, 546–558, doi:10.3762/bjnano.6.57

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  • materials have limitations such as low chemical stability (magnetic component) and harsh cytotoxic effects (fluorescent component) and, hence, require a biocompatible protecting agent. Silica micro/nanospheres have shown promise as protecting agent due to the high stability and low toxicity. This review
  • will cover a full description of MRI-active and fluorescent multifunctional silica micro/nanospheres including the design of the probe, different characterization methods and their application in imaging and treatment in cancer. Keywords: bimodal imaging; fluorescence imaging; magnetic nanoparticles
  • ; organic dyes; quantum dots; silica nanospheres; theranostics; Review 1 Introduction In the modern era of medical diagnosis, X-rays have long played a major role in the clinical imaging of anatomical details of disease sites [1]. However, the development of suitable molecular diagnostic systems for
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Published 24 Feb 2015

Influence of size, shape and core–shell interface on surface plasmon resonance in Ag and Ag@MgO nanoparticle films deposited on Si/SiOx

  • Sergio D’Addato,
  • Daniele Pinotti,
  • Maria Chiara Spadaro,
  • Guido Paolicelli,
  • Vincenzo Grillo,
  • Sergio Valeri,
  • Luca Pasquali,
  • Luca Bergamini and
  • Stefano Corni

Beilstein J. Nanotechnol. 2015, 6, 404–413, doi:10.3762/bjnano.6.40

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  • originated by the coalescence process, in accordance with the experimental observations (see Figure 2). The plasmon resonance linked to the nanospheres and the minor axes of the nanospheroids causes the deep recess (minimum) around 3.5 eV, which slightly blue-shifted with respect to the film thickness ratio
  • dimers or other smaller aggregates. Indeed, for both thicknesses, the simulations provide a good match with the experiments when the quantity of nanospheroids is less than that of the nanospheres (compare Figure 3e with Figure 3c). For tAg = 0.8 nm, the best spectrum reproduction was found for a
  • coordinates. Equation 1 reduces to the well-known Maxwell Garnett formula with spherical inclusions when only nanospheres of the same material are considered (i.e., when i = 1 and L11 = L12 = L13 = 1/3) [10][43][44]: SEM images taken from (a) bare Ag NP deposited on Si/SiOx substrates with tAg = 0.8 nm (given
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Published 09 Feb 2015

Mechanical properties of MDCK II cells exposed to gold nanorods

  • Anna Pietuch,
  • Bastian Rouven Brückner,
  • David Schneider,
  • Marco Tarantola,
  • Christina Rosman,
  • Carsten Sönnichsen and
  • Andreas Janshoff

Beilstein J. Nanotechnol. 2015, 6, 223–231, doi:10.3762/bjnano.6.21

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  • coated gold nanoparticles (>100 kPa). Importantly, this effect seems to be independent of particle shape. Using CTAB-coated gold nanospheres with a mean diameter of 43 nm we found that at a particle concentration of 3 μg/mL already results in a Young’s modulus of E = 42 kPa (Figure 5). Higher particle
  • of cells with GDA results in a shift to lower resonance frequency by a few hundred Hertz, while dissipation grows [14]. The same is observed for CTAB-coated gold nanorods and nanospheres (Figure 6). In good accordance, elasticity measurements of MDCK II cells after GDA fixation with an AFM provides a
  • after reaching confluence by washing with PBS, followed by trypsinization and centrifugation at 110g. Particle synthesis and characterization Gold nanorods and nanospheres were prepared as described previously following the seeded growth method [25]. First, seeds were prepared by adding 0.6 mL of ice
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Published 20 Jan 2015

Functionalization of α-synuclein fibrils

  • Simona Povilonienė,
  • Vida Časaitė,
  • Virginijus Bukauskas,
  • Arūnas Šetkus,
  • Juozas Staniulis and
  • Rolandas Meškys

Beilstein J. Nanotechnol. 2015, 6, 124–133, doi:10.3762/bjnano.6.12

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  • ]. These natural building blocks with a wide range of modifiable properties have become very attractive tools for applications in biotechnology, material science, molecular electronics and related fields [6]. A variety of nanostructures, including nanotubes, nanospheres, nanofibers, nanotapes and hydrogels
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Published 12 Jan 2015

Mammalian cell growth on gold nanoparticle-decorated substrates is influenced by the nanoparticle coating

  • Christina Rosman,
  • Sebastien Pierrat,
  • Marco Tarantola,
  • David Schneider,
  • Eva Sunnick,
  • Andreas Janshoff and
  • Carsten Sönnichsen

Beilstein J. Nanotechnol. 2014, 5, 2479–2488, doi:10.3762/bjnano.5.257

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  • larger in diameter than the actual size of the nanoparticles and the spot color is the plasmon frequency. This correlates to the particle shape: green spots are correlated with single gold nanospheres, while red spots correlate to individual gold nanorods. When the aggregation of two or more particles
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Published 24 Dec 2014

Localized surface plasmon resonances in nanostructures to enhance nonlinear vibrational spectroscopies: towards an astonishing molecular sensitivity

  • Dan Lis and
  • Francesca Cecchet

Beilstein J. Nanotechnol. 2014, 5, 2275–2292, doi:10.3762/bjnano.5.237

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  • the junction between the nanospheres, with a strong dipolar contribution parallel to the substrate. This explains the necessity to use ssp polarization (in the order of SFG, vis, IR) to obtain a strong amplification for such dense nanoparticle layer. As a result, an octadecanethiol SAM chemisorbed on
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Published 28 Nov 2014

Properties of plasmonic arrays produced by pulsed-laser nanostructuring of thin Au films

  • Katarzyna Grochowska,
  • Katarzyna Siuzdak,
  • Peter A. Atanasov,
  • Carla Bittencourt,
  • Anna Dikovska,
  • Nikolay N. Nedyalkov and
  • Gerard Śliwiński

Beilstein J. Nanotechnol. 2014, 5, 2102–2112, doi:10.3762/bjnano.5.219

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  • surface plasmon resonance (SPR) peak around 520 nm resulted in the observable decrease of the film roughness and resistivity [14]. In case of nanostructuring of a thin Au film by a pulsed-laser beam passing through a pinhole (60 μm), the forced arrangement of nanospheres into micro-circular patterns due
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Published 13 Nov 2014

Controlling the dispersion of supported polyoxometalate heterogeneous catalysts: impact of hybridization and the role of hydrophilicity–hydrophobicity balance and supramolecularity

  • Gijo Raj,
  • Colas Swalus,
  • Eglantine Arendt,
  • Pierre Eloy,
  • Michel Devillers and
  • Eric M. Gaigneaux

Beilstein J. Nanotechnol. 2014, 5, 1749–1759, doi:10.3762/bjnano.5.185

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  • dictated by the interaction of the alkyl side chains of DODA with the substrate surface. On HOPG, the DODA–POM hybrid forms small domains of epitaxially arranged straight nanorod structures with their orientation parallel to each other. Conversely, randomly distributed nanospheres are formed when the
  • , DODA–POM hybrids form randomly distributed nanosphere-like assemblies on the hydrophilic mica surface. The vertical height of the nanospheres, as measured by AFM cross-section analysis, were 8.0 ± 0.2 nm, and 17.5 ± 0.5 nm for the hybrids formed from Keggin and WD POM, respectively (Figure 6). A close
  • examination of the cross-section of the nanospheres in Figure 6a shows that they are composed of vertical multi-layered assemblies. The thickness of the first layer is ca. 4.5 nm, while that of the second layer is ca. 3.5 nm, resulting in an overall thickness of ca. 8 nm. The vertical assembly of DODA–POM
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Published 10 Oct 2014

Protein-coated pH-responsive gold nanoparticles: Microwave-assisted synthesis and surface charge-dependent anticancer activity

  • Dickson Joseph,
  • Nisha Tyagi,
  • Christian Geckeler and
  • Kurt E.Geckeler

Beilstein J. Nanotechnol. 2014, 5, 1452–1462, doi:10.3762/bjnano.5.158

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  • and hence carried a negative surface charge. A recent report shows that gold nanospheres attached to a negatively charged cell surface penetrate the cell wall more easily, if they carry positive charges, because the cell membrane tries to restore its previous surface charge distribution by removing
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Published 04 Sep 2014

Liquid fuel cells

  • Grigorii L. Soloveichik

Beilstein J. Nanotechnol. 2014, 5, 1399–1418, doi:10.3762/bjnano.5.153

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Published 29 Aug 2014

Functionalized nanostructures for enhanced photocatalytic performance under solar light

  • Liejin Guo,
  • Dengwei Jing,
  • Maochang Liu,
  • Yubin Chen,
  • Shaohua Shen,
  • Jinwen Shi and
  • Kai Zhang

Beilstein J. Nanotechnol. 2014, 5, 994–1004, doi:10.3762/bjnano.5.113

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  • hydrogen production. Both CuGa2In3S8 (1.91 eV) and AgGa2In3S8 (2.27 eV) showed a quite high photocatalytic activity [62]. Chen and co-workers synthesized hierarchical ZnS–In2S3–CuS nanospheres with a nanoporous structure. A high QE of 22.6% at 420 nm is achieved without loading cocatalysts due to their
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Published 09 Jul 2014

Nanodiamond-DGEA peptide conjugates for enhanced delivery of doxorubicin to prostate cancer

  • Amanee D Salaam,
  • Patrick Hwang,
  • Roberus McIntosh,
  • Hadiyah N Green,
  • Ho-Wook Jun and
  • Derrick Dean

Beilstein J. Nanotechnol. 2014, 5, 937–945, doi:10.3762/bjnano.5.107

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  • tumor types [6][7][8][9]. Currently, there are several clinically approved nanoparticle-based cancer drugs using liposomes, nanoparticle albumin-bound (nab) technology, dendrimers, polymeric, carbon, and metal nanoparticles [6][8]. Gold nanorods, iron magnetic nanoparticles, polymer nanospheres, lipids
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Published 01 Jul 2014

Optimizing the synthesis of CdS/ZnS core/shell semiconductor nanocrystals for bioimaging applications

  • Li-wei Liu,
  • Si-yi Hu,
  • Ying Pan,
  • Jia-qi Zhang,
  • Yue-shu Feng and
  • Xi-he Zhang

Beilstein J. Nanotechnol. 2014, 5, 919–926, doi:10.3762/bjnano.5.105

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  • analysis, the thickness of the adsorbed polymer layer was determined according to Equation 2 [36]: where δ is the width of the polymer layer, da is the hydrodynamic size after polymer adsorption and d0 is the hydrodynamic size of the bare nanospheres. However, the bare nanospheres were not stable. From
  • stabilize nanospheres and prolong their circulation time in vivo. In this experiment, F127 was used to modify the surface of the CdS/ZnS QDs Preparation of in vitro cell imaging Panc-1 cells were maintained in Dulbecco’s modified Eagle’s medium (DMEM, Sigma-Aldrich) supplemented with 10% fetal bovine serum
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Published 27 Jun 2014

Antimicrobial nanospheres thin coatings prepared by advanced pulsed laser technique

  • Alina Maria Holban,
  • Valentina Grumezescu,
  • Alexandru Mihai Grumezescu,
  • Bogdan Ştefan Vasile,
  • Roxana Truşcă,
  • Rodica Cristescu,
  • Gabriel Socol and
  • Florin Iordache

Beilstein J. Nanotechnol. 2014, 5, 872–880, doi:10.3762/bjnano.5.99

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  • -chitosan-magnetite-eugenol (PLA-CS-Fe3O4@EUG) nanospheres by matrix assisted pulsed laser evaporation (MAPLE). Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) investigation proved that the homogenous Fe3O4@EUG nanoparticles have an average diameter of about 7 nm, while the PLA
  • -CS-Fe3O4@EUG nanospheres diameter sizes range between 20 and 80 nm. These MAPLE-deposited coatings acted as bioactive nanosystems and exhibited a great antimicrobial effect by impairing the adherence and biofilm formation of Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa
  • nanoparticles; nanospheres; P. aeruginosa; polylactic acid; S. aureus; Introduction Driven by more and more microbial antibiotic resistance, alternative therapeutic approaches are emerging [1][2][3][4]. Polar and nonpolar, functionalized and non-functionalized magnetite nanostructures have proven successfully
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Published 18 Jun 2014

Antimicrobial properties of CuO nanorods and multi-armed nanoparticles against B. anthracis vegetative cells and endospores

  • Pratibha Pandey,
  • Merwyn S. Packiyaraj,
  • Himangini Nigam,
  • Gauri S. Agarwal,
  • Beer Singh and
  • Manoj K. Patra

Beilstein J. Nanotechnol. 2014, 5, 789–800, doi:10.3762/bjnano.5.91

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  • [21]. Recently it has been found that conversion of three-dimensional polystyrene nanospheres to a two-dimensional nanodisc shape offers a larger contact surface with cell membranes and generates less impact during their interaction, which leads to a binding that is limited to the cell membrane with
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Published 05 Jun 2014

Nanostructure sensitization of transition metal oxides for visible-light photocatalysis

  • Hongjun Chen and
  • Lianzhou Wang

Beilstein J. Nanotechnol. 2014, 5, 696–710, doi:10.3762/bjnano.5.82

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  • ) and then emit shorter wavelength light (300 to 530 nm) for the excitation of m-BiVO4 to further generate electron–hole pairs for photocatalytic degradation. Due to the special upconversion property of carbon nanodots, the carbon nanodots–m-BiVO4 nanospheres can be used as photocatalysts under the
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Published 23 May 2014

Hole-mask colloidal nanolithography combined with tilted-angle-rotation evaporation: A versatile method for fabrication of low-cost and large-area complex plasmonic nanostructures and metamaterials

  • Jun Zhao,
  • Bettina Frank,
  • Frank Neubrech,
  • Chunjie Zhang,
  • Paul V. Braun and
  • Harald Giessen

Beilstein J. Nanotechnol. 2014, 5, 577–586, doi:10.3762/bjnano.5.68

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  • diameter, namely, the size of the used nanospheres. The average radius of the SRRs depends on the PMMA thickness h0 and the azimuthal angle θ: The gap size s depends additionally on the rotated angle φ: After evaporation has been carried out, the sacrificial PMMA layer and the gold mask are removed by
  • – variation of nanostructure density In order to realize different plasmonic applications, the density of the disordered drop-coated nanospheres must be well controlled by suitable concentrations of the negatively charged PS nanospheres and the positively charged PDDA solution. The electrostatic and steric
  • sufficient oxygen plasma etching time has been reached. PS nanospheres of 119 nm diameter were used in all four examples. A variety of different nanostructures fabricated by hole-mask colloidal lithography: (a) ellipses, (b) split-rings, (c) asymmetric double split-rings, (d) dimers, (e) pentamers, (f) three
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Published 06 May 2014

In vitro toxicity and bioimaging studies of gold nanorods formulations coated with biofunctional thiol-PEG molecules and Pluronic block copolymers

  • Tianxun Gong,
  • Douglas Goh,
  • Malini Olivo and
  • Ken-Tye Yong

Beilstein J. Nanotechnol. 2014, 5, 546–553, doi:10.3762/bjnano.5.64

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  • . AuNRs have the unique ability to enhance the electromagnetic field within sub-wavelength regions adjacent to their surfaces under resonance excitation. The optical cross section of AuNRs is comparable to gold nanospheres and nanoshells, but the smaller effective dimension of AuNRs makes them useful for
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Published 30 Apr 2014

Mesoporous cerium oxide nanospheres for the visible-light driven photocatalytic degradation of dyes

  • Subas K. Muduli,
  • Songling Wang,
  • Shi Chen,
  • Chin Fan Ng,
  • Cheng Hon Alfred Huan,
  • Tze Chien Sum and
  • Han Sen Soo

Beilstein J. Nanotechnol. 2014, 5, 517–523, doi:10.3762/bjnano.5.60

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  • , Singapore 138632 Energy Research Institute @ NTU (ERI@N), 1 CleanTech Loop, Singapore 637141 Singapore-Berkeley Research Initiative for Sustainable Energy (SinBeRISE), 1 Create Way, Singapore 138602 10.3762/bjnano.5.60 Abstract A facile, solvothermal synthesis of mesoporous cerium oxide nanospheres is
  • nanospheres, which is a mixed phase of Ce7O12 and CeO2, and can absorb visible light to photocatalytically degrade dyes such as rhodamine B (RhB). The materials characterization of the cerium oxide nanospheres and some mechanistic insights into the photocatalytic process are presented. Findings
  • (CAN) in ethylene glycol and isopropanol as the solvent and reductant was heated up to 130 °C to yield mesoporous cerium oxide nanospheres after work-up. The powder X-ray diffraction (XRD) pattern (Figure 1a) indicates that the as-prepared cerium oxide material can be indexed to a superposition of
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Published 24 Apr 2014

Dye-doped spheres with plasmonic semi-shells: Lasing modes and scattering at realistic gain levels

  • Nikita Arnold,
  • Boyang Ding,
  • Calin Hrelescu and
  • Thomas A. Klar

Beilstein J. Nanotechnol. 2013, 4, 974–987, doi:10.3762/bjnano.4.110

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  • plasmonic shells [27][28]. Loss-compensation in the case of solid gold nanospheres embedded in a gain medium has been experimentally verified by Noginov et al. [29] and more recently confirmed by Strangi et al. [30]. The cancellation of the losses in hybrid materials that comprise resonant nanoparticle
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Published 30 Dec 2013

Probing the plasmonic near-field by one- and two-photon excited surface enhanced Raman scattering

  • Katrin Kneipp and
  • Harald Kneipp

Beilstein J. Nanotechnol. 2013, 4, 834–842, doi:10.3762/bjnano.4.94

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  • aggregates of nanoparticle of various sizes and shapes reaching from dimers [4][5][6][7], and trimers [8] to selfsimilar structures formed by silver- or gold nanospheres [9]. High local fields can also exist in fractal films or cavities of these noble metals [10]. The recently reported super-resolution
  • only 0.00003 % of the surface of the nanoaggregates provide electromagnetic SERS enhancement factors on the order of 1012. For more regular Ag films over nanospheres (AgFON) substrates, it has been found that 0.0003% of the surface provides an enhancement factor larger than 1010 [49] and 0.003% exhibit
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Published 02 Dec 2013
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