MedWorm.com provides a medical RSS filtering service. Over 6000 RSS medical sources are combined and output via different filters. This feed contains the latest items from the 'Plasmonics' source. Mon, 06 Feb 2012 14:01:07 +0100 http://www.medworm.com/index.php?rid=5664033&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Ff6rm30t8lt406362%2F Abstract  The molecular basis of the diversity of fimbrial lectins dictates the extent of adhesion in different types of Escherichia coli strains to mammalian cells. The mechanism of receptor binding by E. coli in eukaryotic cells differs based on the adhesin domains, patterns in the macromolecular structure and the ligand-binding groove. Current sensor technologies utilize biosensors that are based on the carbohydrate moieties that are involved in pathogen adhesion to host cells. Nanoparticles have been extensively used as carriers for pathogen detection. Gold nanoparticles (Au NPs) of 200 nm size were functionalized with two distinct glycoconjugates mannose (Mn–Au NPs) and Neuαc(α2-3)-Gal-(β1-4)Glc–Paa (Sg–Au NPs) in order to investigate primary and fine sugar... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5664033 Thu, 02 Feb 2012 18:13:33 +0100 5664033 http://www.medworm.com/index.php?rid=5635195&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fnr6h3rm763337006%2F Abstract  Modeling of optical properties of spherical core–shell gold–silver and silver–gold nanoparticles (NPs) was carried out based on extended Mie theory for radiation wavelengths in the range 300 ≤ λ ≤ 650 nm. Efficiency factors of absorption, scattering, and extinction of radiation by core–shell NPs in the range of the radii 5–100 nm and in the range of shell thicknesses 0–40 nm were calculated. Results show the nonlinear dependences of optical properties of core–shell gold–silver and silver–gold nanoparticles on radiation wavelengths, core radii, and shell thicknesses. These results can be applied for photonic technologies of nanoparticles. Content Type Journal ArticlePages 1-6DOI 10.1007/s11468-012-9330-zAuthors V. ... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5635195 Tue, 24 Jan 2012 06:50:00 +0100 5635195 http://www.medworm.com/index.php?rid=5635196&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F6246210057818314%2F Abstract  Simulations are presented that demonstrate that the global state of spatial coherence of an optical wavefield can be altered on transmission through an array of subwavelength-sized holes in a metal plate that supports surface plasmons. It is found that the state of coherence of the emergent field strongly depends on the separation between the holes and their scattering strength. Our findings suggest that subwavelength hole arrays on a metal film can be potentially employed as a plasmon-assisted coherence converting device, useful in modifying the directionality, spectrum, and polarization of the transmitted wave. Content Type Journal ArticlePages 1-10DOI 10.1007/s11468-011-9309-1Authors Choon How Gan, Electronics and Photonics Department, Institute of High Pe... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5635196 Tue, 24 Jan 2012 06:49:59 +0100 5635196 http://www.medworm.com/index.php?rid=5603691&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F962543w07112nuxm%2F Abstract  In pH 6.0 Na2HPO4-NaH2PO4 buffer solution and in the presence of cetyltrimethyl ammonium bromide, nanosilver particles were aggregated to a stable suspension. Therein, rhodamine 6G (Rh6G) exhibited three strong surface-enhanced Raman scattering (SERS) peaks at 613, 1,363, and 1,510 cm−1, and their SERS intensities were enhanced when the concentration of Rh6G increased. In the presence of Hg2+, the SERS intensity decreased greatly owing to formation of stable Rh6G-HgBr42− ternary association complex molecules as well as its particles. In the optimal condition, the decreased SERS intensity at 613 cm−1 responds linearly with the concentration of Hg2+ over 25–2,000 nmol/L. Thus, a new sensitive SERS method has been proposed for the determinati... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5603691 Sat, 14 Jan 2012 06:54:37 +0100 5603691 http://www.medworm.com/index.php?rid=5603692&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fx6l458041x029304%2F Abstract  A new technique for localization of the light in subwavelength scale is proposed by using two adjacent metallic wedges, which are made by different metals, i.e., Al and Ag. Green’s function surface integral equation method is exploited to numerically calculate magnetic field at different points. The results illustrate that by controlling the phase difference between two surface plasmon polariton waves propagating on the sides of the first wedge and the distance between two wedges the amplitude and the phase of SPP waves generated on the sides of the second wedge can be adjusted. Content Type Journal ArticlePages 1-5DOI 10.1007/s11468-012-9327-7Authors Nafiseh Zavareian, Laser and Plasma Research Institute, Shahid Beheshti University, Evin, GC, Tehran, Iran ... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5603692 Fri, 13 Jan 2012 16:50:29 +0100 5603692 http://www.medworm.com/index.php?rid=5592711&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F27k910022276k850%2F Abstract  Flat-top transmission bands are found in a plasmonic structure constructed by periodic ring resonators. Fabry–Perot effects can be suppressed in a set of parameters determined by an effective medium method. Two kinds of transmission bands with flat-top profiles can emerge due to either ring resonance or Bragg scattering. These bands are both red shifted when the distance of rings increases. Both transfer matrix method and finite difference time domain method are utilized to investigate the flat-top bands. The proposed structure can be employed as a plasmonic band-pass filter and might be useful in the field of integrated optoelectronics. Content Type Journal ArticlePages 1-5DOI 10.1007/s11468-011-9325-1Authors Jin-Xiong Tan, State Key Laboratory of Optoele... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5592711 Mon, 09 Jan 2012 06:32:23 +0100 5592711 http://www.medworm.com/index.php?rid=5592712&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F618132837206j5k1%2F Abstract  The localized surface plasmon resonance dependence on surrounding medium refractive index of Ag, Al, Au, and Cu nanoparticles is examined by electrodynamic approach. The refractive index sensitivity and sensing figure of merit (FOM) dependence of selected metal nanoparticles with similar geometry shows that although, sensing relevant parameters are shape (i.e., aspect ratio), and material dependent below the width 20 nm, but above this size these parameters are material independent under similar geometrical conditions. We have concluded that at optimum size, however, Al shows much higher refractive index sensitivity (RIS) in comparison to Au, Cu, and Ag, but FOM is higher for Ag in comparison to other metals. The observed sensing behavior is expected due to p... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5592712 Sat, 07 Jan 2012 06:45:13 +0100 5592712 http://www.medworm.com/index.php?rid=5576528&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fx26165952457u55r%2F Abstract  Making use of the FDTD simulation, we study light transmission properties of a composite coaxial/circular aperture milled in a thin metallic film. Representing the aperture as consisting of segments of coaxial and hollow waveguides, connected in series, we show that there are three characteristic frequencies (the cutoff frequencies of the coaxial and hollow waveguides and the frequency of a longitudinal standing wave in the coaxial waveguide segment) and four regimes of operation (bounded by these frequencies, as well as by low- and high-frequency limits) which determine the behavior of the transmission efficiency. For two regimes of operation (for frequencies between the cutoff frequency of the coaxial waveguide and the resonant frequency of the longitudinal stan... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5576528 Fri, 06 Jan 2012 16:48:01 +0100 5576528 http://www.medworm.com/index.php?rid=5568569&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fn6224364t6w73w53%2F Abstract  We theoretically study the evolution of the resonant modes and the transmission suppression (TS) effect in a perforated ultrathin metallic film (PUMF) with a periodic triangular array of holes. It is found that the properties of different resonances change as the hole radius increases, and the non-monotonic shift of resonant frequency can be interpreted qualitatively from the electric field distribution other than the Fano model. In addition, we analyze the strong mode interaction phenomenon in PUMF. When the diameter of holes approaches to four fifths of the lattice constant, the coupling between dipolar resonance and decapolar resonance can lead to an anticrossing and a large Rabi splitting, which is not available in PUMFs with square lattice; the resulting hybr... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5568569 Wed, 04 Jan 2012 16:48:13 +0100 5568569 http://www.medworm.com/index.php?rid=5568570&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fg468561187363438%2F Abstract  We propose a wide-field super-resolved optical microscopic imaging technique based on subwavelength slit arrays embedded in a thin silver film to generate surface plasmon (SP) standing wave interference patterns. These fringes carrying high spatial frequency information serve as excitation profiles to excite the nanoscale fluorescence objects. The super-resolved fluorescence density distribution is reconstructed from a weight sum of a series of fluorescence images with differently phase-shifted SP standing wave illumination. Simulation and experimental results show that the lateral resolution of the reconstructed fluorescence density image is enhanced by 0.28 λ SP in two dimensions, which is twofold better than that of conventional high numerical aperture fluor... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5568570 Wed, 04 Jan 2012 06:58:45 +0100 5568570 http://www.medworm.com/index.php?rid=5568571&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F90v82x186t152535%2F Abstract  The properties of the terahertz resonant surface plasmons wave on the carbon nanotube film and dielectric interface have been investigated. As a first step towards engineering terahertz SPPs-like surface modes, we present a computer experiment to demonstrate that the carbon nanotube film surface can also be employed to concentrate and guide the terahertz SPPs wave. The carbon nanotube film is modeled in an experimentally realizable geometry. It is shown that a unique electromagnetic surface mode in terahertz region can be supported along the carbon nanotube film/dielectric interface when the free-space broadband terahertz pulse is incident on the carbon nanotube film with subwavelength gratings. Comparing with noble metals, plasmonic nano-structure materials based... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5568571 Thu, 29 Dec 2011 06:42:35 +0100 5568571 http://www.medworm.com/index.php?rid=5556680&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F9j18q257t0105551%2F Abstract  Based on the strongly coupled-resonator effects, a high wavelength-resolution plasmonic Y-splitter, consisting of a Y-branch metal–insulator–metal waveguide with a baffle in each channel, is numerically investigated using the finite element method. Due to the coupling of different resonators (with nearly equal bandwidths) in the Y-splitter, sharp and asymmetric transmission spectra occur. This greatly increases the wavelength resolution of the Y-splitter to be Δλ ≈ 15 nm, which is significantly narrower than the bandwidth of the single resonator (Δλ FWHM ≈ 110 nm). An analytic model based on the scattering matrix theory is provided to describe and explain this phenomenon. Content Type Journal ArticlePages 1-5DOI 10.1007/s11468-011-... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5556680 Wed, 28 Dec 2011 06:53:22 +0100 5556680 http://www.medworm.com/index.php?rid=5542129&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fa585t0t35l6nlt84%2F We present a new approach to surface plasmon microscopy with high refractive index sensitivity and spatial resolution that is not limited by the propagation length of surface plasmons. It is based on a nanostructured metallic sensor surface supporting Bragg-scattered surface plasmons. We show that these non-propagating surface plasmon modes are excellently suited for spatially resolved observations of refractive index variations on the sensor surface owing to their highly confined field profile perpendicular to as well as parallel to the metal interface. The presented theoretical study reveals that this approach enables reaching similar refractive index sensitivity as regular surface plasmon resonance (SPR) microscopy and offers the advantage of improved spatial resolution when obser... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5542129 Tue, 20 Dec 2011 16:48:12 +0100 5542129 http://www.medworm.com/index.php?rid=5520195&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F2534126n4v47281x%2F Abstract  In the present paper, the acoustic surface plasmon (ASP) dispersion is investigated on nanostructured Cu(111) by angle-resolved high-resolution electron energy loss spectroscopy (HREELS). The surface is prepared by ion bombardment at different crystal temperatures and ion fluences, following the recipes given by J. Naumann et al. (Surf Sci 388:212–219, 1997). We demonstrate that, at room temperature, the ASP survives to the disordering introduced by sputtering. The slope of the dispersion curve is thereby slightly reduced with respect to the one measured on pristine Cu(111), in accord with the disorder induced up-shift of the Shockley surface state. When ion bombardment is performed at 393 K and the surface restructures at the nanoscale forming hexagonal hol... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5520195 Thu, 15 Dec 2011 06:44:30 +0100 5520195 http://www.medworm.com/index.php?rid=5512122&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Ft8126n6q4k444u3h%2F Abstract  We have demonstrated experimentally a one-way magnetic surface plasmon (MSP) electromagnetic (EM) waveguide in the microwave range based on the magnetic photonic crystals (MPCs). The waveguide exhibits asymmetric transmission of EM waves in the frequency range near the MSP resonance for an MPC, such that a significant one-way propagation can be observed in the channel between the two MPC slabs, each in an external static magnetic field (ESMF) of opposite directions. The one-way waveguide is not only immune to interstitial metal defects but also robust against the disorder of rod position. Furthermore, its working frequency can be flexibly tuned by an ESMF, which makes it more favorable for the design of EM devices. The physics is related to the broken time-reversa... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5512122 Wed, 14 Dec 2011 06:56:11 +0100 5512122 http://www.medworm.com/index.php?rid=5512123&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F3376385831610436%2F Abstract  The optical beam generated by a micro triangular prism is presented to excite surface plasmon polaritons (SPPs) on a single silver nano slit. The electromagnetic fields generated by the micro triangular prism and the excited surface plasmon polaritons are simulated with finite-difference time-domain method. Compared with directly normal incident beam, the efficiency of SPPs’ excitation with the beam generated by the micro triangular prism is highly improved. Content Type Journal ArticlePages 1-5DOI 10.1007/s11468-011-9319-zAuthors Dengfeng Kuang, Institute of Modern Optics, the Key Laboratory of Optical Information Science and Technology of the Education Ministry of China, Nankai University, Tianjin, 300071 ChinaZhongxun Du, Institute of Modern Optics, the K... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5512123 Tue, 13 Dec 2011 17:02:15 +0100 5512123 http://www.medworm.com/index.php?rid=5512125&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F702819m847168436%2F Abstract  Localized surface plasmon singularities from metal nanoparticles in active media are investigated on the basis of classic linear electrodynamics. It is found that the gain threshold is inversely proportional to the shape factor of the particle. When relating this phenomenon to the plasmonic field-enhanced emission from gain units, we show that the maximum electric field around spheroidal particles impacts upon the gain threshold via a two-exponential decay function. Our results provide a way to reduce the gain requirement in metal nanoparticle-based spaser or random laser systems. Content Type Journal ArticlePages 1-5DOI 10.1007/s11468-011-9313-5Authors Min Cao, State Key Laboratory of Bioelectronics and Jiangsu Laboratory for Biomaterials and Devices, Southe... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5512125 Mon, 12 Dec 2011 06:32:53 +0100 5512125 http://www.medworm.com/index.php?rid=5512124&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Ff65170l110h44240%2F Abstract  In this work, we investigated the effect of nanosecond laser irradiation at 532 nm on precipitation of Ag nanoparticles (NPs) in soda lime glasses doped with silver in the Ag + –Na +  ion-exchange process. Formation and subsequent modification of Ag NPs during laser irradiation were studied by on-line extinction measurements making use of the localized surface plasmon resonance (LSPR). These investigations were further completed using scanning and transmission electron microscopies to examine the average size and distribution of nanoparticles within the sample. It has been shown that formation of NPs, its kinetics and the particle size strongly depend on the fluence and the total number of deposited laser pulses. It has been found that Ag NPs form af... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5512124 Mon, 12 Dec 2011 06:32:53 +0100 5512124 http://www.medworm.com/index.php?rid=5500942&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fc1n538g765777t32%2F Abstract  Top-illumination tip-enhanced Raman scattering (TI-TERS) has recently emerged as a promising near-field vibrational spectroscopy method that can be adapted on an upright optical microscope. With a relatively simplified optics, TI-TERS can probe both opaque and transparent samples making them a promising tool in nanoscale chemical analysis. One of the critical components of TI-TERS is the plasmonic nano-tip used to enhance the Raman spectroscopic signature. Herein, we numerically studied the near-field optical properties of conventional gold tip (20 nm radius of curvature) and two varieties of optical antenna-based tips in the context of TI-TERS. Optical antenna-based tips included a 40-nm gold nanoparticle attached to a dielectric tip and a 50-nm equilateral ... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5500942 Fri, 09 Dec 2011 17:07:08 +0100 5500942 http://www.medworm.com/index.php?rid=5492385&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Frr0q34q20652l548%2F Abstract  We demonstrated the near-field optical transmission properties of nanogratings with spoke and rings structures through a near-field scanning optical microscope, and the far-field optical transmission properties with different polarization angles are investigated with an optical microscope. Our experimental results verified the polarization properties of the nanograting structures and further demonstrated the experimental results are supported by the finite difference time domain theoretical simulation. The optical microscope imaging of the spoke and ring structures also show that the grating structures can disperse visible light of different wavelengths. Content Type Journal ArticlePages 1-8DOI 10.1007/s11468-011-9320-6Authors Rongjing He, School of Physical... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5492385 Wed, 07 Dec 2011 10:47:42 +0100 5492385 http://www.medworm.com/index.php?rid=5492386&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F1u5h620350kul760%2F Abstract  In this paper, we study the nanoscale-focusing effect in the far field for a spiral plasmonic lens with a concentric annular groove by using finite-difference time domain simulation. The simulation result demonstrates that a left-hand spiral plasmonic lens can concentrate an incident right-hand circular polarization light into a focal spot at the exit surface. And this spot can be focused into far field due to constructive interference of the scattered light by the annular groove. The focal length and the focal depth can be adjusted by changing the groove radius and number of grooves within a certain range. These properties make it possible to probe the signal of spiral plasmonic lens in far field by using conventional optical devices. Content Type Journal Art... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5492386 Wed, 07 Dec 2011 10:47:41 +0100 5492386 http://www.medworm.com/index.php?rid=5492387&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fql04531l717q0265%2F Abstract  We investigate the wave transmissions through an index-near-zero (INZ) or epsilon-near-zero (ENZ) metamaterial containing various kinds of coated cylindrical defects. We find that thin coatings of the defects can dramatically change the transmission behaviors. For example, perfect magnetic conductor (PMC) defects embedded in an INZ or ENZ metamaterial yield total reflections for transverse magnetic polarized waves (Hao et al., Appl Phys Lett 96:101109, 2010). However, if the PMC defects are coated with dielectric shells, total transmissions could be achieved by tuning their permittivity values or geometric sizes. The permittivity differences of dielectric shells for total reflections and transmissions in the INZ or ENZ metamaterial could be very small, implying pot... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5492387 Wed, 07 Dec 2011 10:47:40 +0100 5492387 http://www.medworm.com/index.php?rid=5492388&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F11435710h80768p6%2F Abstract  High-resolution electron energy-loss spectroscopy has been used to study the π plasmon in monolayer graphene grown on Pt(111). A quadratic dispersion has been observed, in contrast to the linear dispersion reported for monolayer graphene grown on SiC(0001) and in agreement with recent experiments on graphene/Ni(111). Despite the weak interaction of the monolayer graphene with the Pt(111) surface, our results indicate that the screening by the underlying metal substrate strongly influences both the dispersion relation and the damping processes of the plasmon mode of π electrons. Content Type Journal ArticlePages 1-8DOI 10.1007/s11468-011-9317-1Authors Antonio Politano, Departamento de Física, Universidad Autónoma de Madrid, Campus Universitario de Cantobla... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5492388 Tue, 06 Dec 2011 17:02:15 +0100 5492388 http://www.medworm.com/index.php?rid=5482776&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F526q73416t31u0q5%2F Abstract  Rhodamine B and Rhodamine 6G molecules were doped in polymethyl methacrylate solution. Then a silver film on the glass substrate was spin coated with the mixed solution to get a multilayer film. Under the irradiation of a 532-nm green laser, broadband surface plasmons (SPs) on the silver film were generated due to the coupling between the broadband fluorescence and the SP modes allowed in the multilayer film. From the back focal plane image of a leakage radiation microscopy, propagation constants of SP waves at different wavelengths were derived. Numerical calculations were also carried out and were consistent with the experimental results. Content Type Journal ArticlePages 1-4DOI 10.1007/s11468-011-9308-2Authors Douguo Zhang, Institute of Photonics, Departm... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5482776 Mon, 05 Dec 2011 17:35:39 +0100 5482776 http://www.medworm.com/index.php?rid=5482777&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F4376586j7t6ll582%2F Abstract  The development of gold nanorod plasmonic sol–gel polymer is presented and characterised with respect to its sensitivity to refractive index change. Structural characterisation of the polymer was conducted using Raman microscopy and energy dispersion spectroscopy while plasmonic function was investigated using UV/VIS spectroscopy. Refractive index sensitivities utilising the peak wavelength shift of the localised surface plasmon resonance were shown to be of the order of 2,338 nm per refractive index unit; in addition, peak absorbance was considered as an alternative measure. Furthermore, demonstration of sensitivity to biomolecule interaction has been shown as a model study. Strong photoluminescence was observed during Raman studies that restricts the pote... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5482777 Mon, 05 Dec 2011 06:33:07 +0100 5482777 http://www.medworm.com/index.php?rid=5482778&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fu473822n6630rvv5%2F Abstract  Laser irradiation induced changes of optical parameters in the layered structures which consist of gold nanoparticles and amorphous As2S3 were investigated and modelled in the framework of Bruggeman approximation for localised plasmons with aim to show the influence of plasmon fields on the optical recording process. Content Type Journal ArticlePages 1-5DOI 10.1007/s11468-011-9312-6Authors Stepan Charnovych, Institute of Physics, University of Debrecen, Debrecen, 4026 HungaryNicholas Dmitruk, Institute of Semiconductors Physics, Kyyv, UkraineIvan Voynarovych, Institute of Solid State Physics, Uzhgorod National University, Uzhgorod, 88000 UkraineNatalia Yurkovich, Institute of Solid State Physics, Uzhgorod National University, Uzhgorod, 88000 UkraineSandor Koken... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5482778 Fri, 02 Dec 2011 17:30:11 +0100 5482778 http://www.medworm.com/index.php?rid=5447473&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Ff50691311mu04725%2F Abstract  We developed a method to fabricate a periodic array of three-dimensional crescent-like holes (3DCLH) via an inverted hemispherical colloidal lithography. It is found that there exists an extraordinary optical transmission in this non-planar perforated periodic array of 3DCLH when the electric field of the incident light is perpendicular to the cross-line of the crescent-like hole. This extraordinary optical peak is insensitive with the incident angles and sensitive with the angle between the electric field of the incident light to the cross-line of the 3DCLH. Numerical simulation based on finite-difference time-domain method reveals that this peak is caused by an asymmetric localized surface plasmon resonance. This structure might be useful for the optical sensing... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5447473 Mon, 21 Nov 2011 18:05:07 +0100 5447473 http://www.medworm.com/index.php?rid=5427831&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fd115632135k83604%2F Abstract  The excitation of surface plasmon polaritons (SPP) at a gold–vacuum interface by femtosecond light pulses mediated by organic nanofiber-induced dielectric perturbations is observed using interferometric time-resolved photoemission electron microscopy. The experimental data are quantitatively reproduced by analytic simulations, where the nanofibers are considered as superior source of the SPP emission. The flexibility and tuneability of phenylene-based nanofibers in their morphology and intrinsic optical properties open up future applications to fabricate custom-designed nanoscale sources of SPP. Content Type Journal ArticlePages 1-8DOI 10.1007/s11468-011-9301-9Authors Till Leißner, IEAP, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, GermanyKasper T... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5427831 Wed, 16 Nov 2011 16:43:25 +0100 5427831 http://www.medworm.com/index.php?rid=5404649&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fwt26576436r86749%2F Abstract  The influence of C60 adsorption on the properties of surface plasmon polaritons on small Ag islands is discussed. Under illumination with UV light as well as under illumination with femtosecond laser pulses, a decrease of the photoemission yield with increasing C60 coverage is observed. With angular resolved measurements, changes of the band structure during deposition are studied. Based on these experiments, an increase of the work function with increasing coverage is measured. In two photon photoemission, the surface plasmons are imaged as a periodic moiré pattern, the wavelength of which changes because of a modified effective surface dielectric function. Our findings imply that the wavelength of the plasmon wave becomes shorter as a result. Finally, a decrease... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5404649 Fri, 11 Nov 2011 12:49:02 +0100 5404649 http://www.medworm.com/index.php?rid=5404651&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fr80155l53586t72v%2F Abstract  In the present study, we report the first fiber optic glucose sensor utilizing localized surface plasmon resonance of metal nanoparticles. The fiber was bent in the form of a U-shaped probe for point detection and sensitivity enhancement. The probe was prepared by first attaching gold nanoparticles on the optical fiber core and then immobilizing glucose oxidase over it. The sensor operates in the intensity modulation scheme in which the absorbance is measured with respect to the changes in the glucose concentration. The presence of glucose in the vicinity of the sensing region changes the refractive index of the film due to the chemical reactions with glucose oxidase. The absorbance of the metal nanoparticle changes significantly due to local refractive index chan... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5404651 Tue, 08 Nov 2011 16:48:44 +0100 5404651 http://www.medworm.com/index.php?rid=5404650&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F2642h35445pv0242%2F Abstract  An efficient circuit model is proposed for studying the electromagnetic characteristics of rectangular plasmonic cavities. The proposed model comprised a finite size transmission line terminated by scalar load impedances at its both ends. It is capable of the fast extraction of resonance frequencies, quality factors, and mode profiles of plasmonic resonators made by carving rectangles in metallic medium. The accuracy of the proposed model is assessed using the fully numerical finite difference time domain technique. It is employed for analysis and design purposes. Content Type Journal ArticlePages 1-8DOI 10.1007/s11468-011-9300-xAuthors Mohsen Rezaei, Electrical Engineering Department, Sharif University of Technology, Tehran, 11365-9363 IranMehdi Miri, Electr... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5404650 Tue, 08 Nov 2011 16:48:44 +0100 5404650 http://www.medworm.com/index.php?rid=5404652&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fd508j333526101nw%2F Abstract  A fluorescence microscope taking advantage of plasmonic coupling is in-proof demonstrated. Silver nano-wires and nano-particles are chosen as the metallic nano-objects, which are put on a silver film with the Rhodamine B-doped PMMA film as the spacer. Plasmonic coupling between the metallic nano-objects and the Ag film will induce either fluorescence quenching or enhancement dependent on the thickness of the spacer layer, which both enhance the contrast of the fluorescence images. Our experiment provides a feasible method to enhance the contrast of fluorescence microscope, which has potential applications in fluorescence-based imaging or sensing. Content Type Journal ArticlePages 1-6DOI 10.1007/s11468-011-9295-3Authors Douguo Zhang, Institute of Photonics, D... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5404652 Tue, 08 Nov 2011 06:50:41 +0100 5404652 http://www.medworm.com/index.php?rid=5396498&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fqq37362p6326g011%2F We report the design, fabrication, and characterization of a periodic grating of shallow rectangular grooves in a metallic film with the goal of maximizing the coupling efficiency of an extended plane wave (PW) of visible or near-infrared light into a single surface plasmon polariton (SPP) mode on a flat metal surface. A PW-to-SPP power conversion factor >45% is demonstrated at a wavelength of 780 nm, which exceeds by an order of magnitude the experimental performance of SPP grating couplers reported to date at any wavelength. Conversion efficiency is maximized by matching the dissipative SPP losses along the grating surface to the local coupling strength. This critical coupling condition is experimentally achieved by tailoring the groove depth and width using a focused ion b... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5396498 Fri, 04 Nov 2011 16:47:56 +0100 5396498 http://www.medworm.com/index.php?rid=5396499&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F48247807u8515612%2F This study investigated the time-evolved photonic Bloch oscillations (PBOs) in a multi-layered fishnet structure (MLFS) with both a negative refraction index (NRI) and a positive refraction index (PRI) at different transmission bands. The PBOs in MLFS are generated by the Bragg reflection and total internal reflection of the incident pulse undergoing at the two opposite ends of the MLFS. The amplitude and period of PBOs in MLFS with both effective NRI and PRI are almost independent of the central frequency of the incident pulse. Content Type Journal ArticlePages 1-6DOI 10.1007/s11468-011-9296-2Authors Bo Han Cheng, Department of Photonics, National Cheng Kung University, Tainan, 701 Taiwan, Republic of ChinaYung-Chiang Lan, Department of Photonics, National Cheng Kung University... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5396499 Thu, 03 Nov 2011 16:53:02 +0100 5396499 http://www.medworm.com/index.php?rid=5396500&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fb0p6g61102g71r00%2F Abstract  We design a new nanofocusing lens for far-field practical applications. The constructively interference of cylindrical surface plasmon launched by the subwavelength metallic structure can form a subdiffraction-limited focus, which is modulated by the dielectric grating from the near field to the far field. The principle of designing such a far-field nanofocusing lens is elucidated in details. The numerical simulations demonstrated that nanoscale focal spot (0.12λ 2) can be realized with 3.6λ in depth of focus and 4.5λ in focal length by reasonably designing parameters of the grating. The focusing efficiency can be 7.335, which is much higher than that of plasmonic microzone plate-like lenses. A blocking chip can enhance the focusing efficiency further as the ref... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5396500 Thu, 03 Nov 2011 16:53:01 +0100 5396500 http://www.medworm.com/index.php?rid=5396501&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F25103kv48m827158%2F Abstract  Using numerical simulations, we examine the change in plasmon resonance behavior in gold nanorod structures that have a V shape. The reduction in symmetry compared to linear rods causes two different longitudinal-type resonances to appear in a single structure, and the relative intensity and hybridization of these can be controlled by varying the angle of the arms of the “V.” The resonances may also be selectively excited by controlling the polarization of the incident light, thereby providing a convenient way to control a nanoscale optical electric field using far-field parameters. For example, the wavelength at which a strong resonance occurs in the V-shaped structures studied can be switched between 630 and 900 nm by a 90° rotation of the polarization... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5396501 Wed, 02 Nov 2011 16:57:57 +0100 5396501 http://www.medworm.com/index.php?rid=5396502&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fp531745636224004%2F Abstract  Active plasmonic devices are mostly designed at visible frequencies. Here, we propose an active terahertz (THz) plasmonic lens tuned by an external magnetic field. Unlike other tunable devices where the tuning is achieved by changing the plasma frequency of materials, the proposed active lens is tuned by changing the cyclotron frequency through manipulating magnetoplasmons (MPs). We have theoretically investigated the dispersion relation of MPs of a semiconductor–insulator–semiconductor structure in the Voigt configuration and systematically designed several lenses realized with a doped semiconductor slab perforated with sub-wavelength slits. It is shown through finite–difference time–domain simulations that THz wave propagating through the designed struct... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5396502 Wed, 02 Nov 2011 05:49:41 +0100 5396502 http://www.medworm.com/index.php?rid=5396503&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fx2127r7x0624722m%2F We report the synthesis of silver nanodecahedrons (NDs) for extending the localized surface plasmon resonance (LSPR) of silver nanostructures from blue to green-orange (~590 nm), which will enable much wider application opportunities using common laser light sources. In our photo-assisted method, we use a light-emitting-diode (LED) to control regrowth of silver ND from precursor seeds. Highly uniform silver NDs are synthesized when the LED emission peak coincides with the LSPR peak of the seeds. A two-step process involving precursor self-transformation into silver nanoprisms and nanoplates, and subsequent photo-activated regrowth of silver NDs has been proposed. Surface-enhanced Raman scattering of silver NDs in different sizes has been studied, and the average enhancement fact... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5396503 Wed, 02 Nov 2011 05:49:40 +0100 5396503 http://www.medworm.com/index.php?rid=5374799&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Ff84418v385k1n8g5%2F Abstract  In pH 5.5 2-(N-morpholino)-ethanosulfonic acid buffer solution containing 0.0125 M NaCl at 80 °C, the single-stranded substrate DNA hybrid with enzyme DNA to form double-stranded DNA (dDNA). The substrate chain of dDNA could be cracked catalytically by UO22+ to produce a short single-stranded DNA (ssDNA) that adsorbed on the nanogold (NG) surface to form stable NGssDNA conjugate, and the unadsorbed NG take place aggregation to produce the NG aggregations in blue color. Both NG and NGssDNA exhibited strong catalytic activity on the gold particle reaction between HAuCl4 and ascorbic acid that can be monitored by resonance scattering (RS) spectral technique at 620 nm. However, the catalytic effect of NG aggregation was very weak and it cannot be se... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5374799 Fri, 28 Oct 2011 17:23:05 +0100 5374799 http://www.medworm.com/index.php?rid=5374800&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fk366406801022333%2F Abstract  The fluorescence quenching efficiency of an emitter close to a gold nanodisk is investigated by theoretical calculation based on the modified quasi-static approximation and fluorescence energy transfer under dipole–dipole coupling. The calculation results show that the surface plasmon resonance (SPR) absorption is the key factor to affect the quenching efficiency. Because of the asymmetric shape of the gold disk, the light absorption depends on both particle volume and aspect ratio (AR). Thus, the AR cannot control the quenching efficiency of gold nanodisk alone. Whether the disk volume is fixed or not may bring different changing way of AR-controlled quenching efficiency. Increasing the AR leads to the quenching efficiency of perpendicular mode start to decreas... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5374800 Thu, 27 Oct 2011 15:45:48 +0100 5374800 http://www.medworm.com/index.php?rid=5281242&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fd4523075221h7w97%2F Abstract  The optical properties of multi-metal nanocomposites made from Cobalt (Co), and Silver (Ag) are analyzed theoretically within the mean field approximation, and experimentally verified using absorption spectroscopy. The experimental system was modeled as a thin layer composed of hemispherical nanoparticles formed by grains of Co and Ag in contact with air and the SiO substrate. The main aspects of the absorption curve, such as the shape and spectral location of the localized surface plasmon resonance, are well captured by a simple self-consistent mixing model using a modified Maxwell-Garnett approach and the Milton lower bound. Content Type Journal ArticlePages 1-5DOI 10.1007/s11468-011-9286-4Authors Hernando Garcia, Department of Physics, Southern Illinois Un... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5281242 Tue, 27 Sep 2011 06:16:54 +0100 5281242 http://www.medworm.com/index.php?rid=5281241&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fw20087421645r312%2F Abstract  We experimentally demonstrate a large third-order nonlinear susceptibility for a nanocomposite made of poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] doped with silver nanoprisms at 1,550 nm, achieved based on nonlinearity enhancement associated with strong surface plasmon resonance. The nonlinear refractive index reaches −1.37 × 10−12 m2/W, which is three orders of magnitude larger than that of pure poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene]. An ultrafast response time of 18.7 ps is reached using fast energy transfer from excited states of organic molecules to silver nanoprisms. A low-power and ultrafast nanocomposite photonic crystal all-optical switching is also realized. Content Type Journal ArticlePages 1-7... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5281241 Tue, 27 Sep 2011 06:16:54 +0100 5281241 http://www.medworm.com/index.php?rid=5281243&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F5583q516733n1121%2F Abstract  One way to compensate for the surface plasmon polariton (SPP) propagation losses is to use a gain medium. However, simply ensuring high enough gain is not sufficient because it may violate the bounded character of the wave. Therefore, a detailed theoretical analysis is needed for the determination of the conditions for lossless or amplified SPP propagation. Here presented is an exact theoretical analysis of the SPP propagation in the case of an infinite metal/gain medium boundary. It is shown that the conditions for lossless/amplified SPP propagation can be conveniently examined and presented as a simply connected region in the complex plane of the gain medium dielectric function. Effective and minimum gain parameters are introduced, which facilitates the simultan... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5281243 Tue, 27 Sep 2011 06:16:53 +0100 5281243 http://www.medworm.com/index.php?rid=5246017&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F7433x12gv2x15045%2F Abstract  Periodic arrays of plasmonic nanopillars have been shown to provide large, uniform surface-enhanced Raman scattering (SERS) enhancements. We show that these enhancements are the result of the combined impact of localized and propagating surface plasmon modes within the plasmonic architecture. Here, arrays of periodically arranged silicon nanopillars of varying sizes and interpillar gaps were fabricated to enable the exploration of the SERS response from two different structures; one featuring only localized surface plasmon (LSP) modes and the other featuring LSP and propagating (PSP) modes. It is shown that the LSP modes determine the optimal architecture, and thereby determine the optimum diameter for the structures at a given incident. However, the increase in t... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5246017 Mon, 19 Sep 2011 15:40:40 +0100 5246017 http://www.medworm.com/index.php?rid=5217521&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fkq13w7k2u862376j%2F Abstract  Nanocomposite (NC) thin films with noble metal nanoparticles embedded in a dielectric material show very attractive plasmonic properties due to dielectric and quantum confinement effects. For single component nanoparticles (NPs), the plasmon resonance frequency can only be tuned in a narrow range. Much interest aroused in bimetallic nanoparticles (BNPs), however many wet chemical approaches do not allow large variation of the NP alloy composition and filling factor. Here, we report a vapor phase co-deposition method to produce polymer–metal NCs with embedded Ag1 − x Cu x alloy particles. The method allows production of NPs with controlled alloy composition (x), metal filling (f) and nanostructure in a protecting Teflon AF matrix. The nanostructure size an... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5217521 Fri, 09 Sep 2011 05:48:21 +0100 5217521 http://www.medworm.com/index.php?rid=5203893&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fd655243865122566%2F Abstract  Electronic excitations of single ZnO rectangular nanorod have been investigated by electron energy-loss spectroscopy in conjunction with scanning transmission electron microscopy (STEM-EELS). We focus primarily on the surface excitations greatly enhanced at the grazing incidence parallel to the surfaces of ZnO nanorods. An uncommon kind of surface excitation known as surface exciton polaritons occurring near interband transitions is found to dominate in the spectral range between the band gap at 3.4 eV and the surface plasmon peak at 15.8 eV. In addition, the dielectric function of ZnO up to 25 eV has also been derived from the bulk excitation spectra using the Kramers–Kronig analysis on a single nanorod. Theoretical EELS simulations are also comp... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5203893 Mon, 05 Sep 2011 16:16:01 +0100 5203893 http://www.medworm.com/index.php?rid=5194723&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fd122216127j04215%2F Abstract  This paper analyzes how dual-mode surface plasmon resonance sensors can be further improved if one were to introduce small (∼20 nm) gaps in the film surface. First, a figure of merit, the sensor’s limit of detection (LOD), is defined in order to optimize the design of the nano-gap sensor. Secondly, the LOD of this design is compared with that of an optimized planar dual-mode design. Through this analysis, it is shown that the LOD of the planar sensor can be improved upon by around a factor of 7 when compared with the nano-gap-enhanced design. Furthermore, with the nano-gap design, the lower wavelength plasmon mode demonstrates remarkably improved selectivity when compared with the conventional sensor. In order to explain these results, the dispersion of e... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5194723 Fri, 02 Sep 2011 05:52:37 +0100 5194723 http://www.medworm.com/index.php?rid=5194724&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fvn6090561785027m%2F Abstract  We have theoretically studied and optimized the field enhancement and temporal response of single and coupled bimetal Ag/Au core–shell nanoparticles (NPs) with a diameter of 160 nm and compared the results to pure Ag and Au NPs. Very high-field enhancements with an amplitude reaching 100 (with respect to the laser field centered at 800 nm) are found at the center of a 2-nm gap between Ag/Au core–shell dimers. We have explored the excitation of the bimetal core–shell particles by Fourier transform-limited few-cycle optical pulses and identified conditions for an ultrafast plasmonic decay on the order of the excitation pulse duration. The high-field enhancement and ultrafast decay makes bimetal core–shell particles interesting candidates for applica... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5194724 Fri, 02 Sep 2011 05:52:34 +0100 5194724 http://www.medworm.com/index.php?rid=5194725&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F076360358175k611%2F Abstract  The magnetic surface polaritons (MSPs) mode rarely exists in natural materials, mainly due to their limited magnetic response. In order to understand the relationship between the MSPs mode and the limited magnetic response, we theoretically derive a general dispersion equation of the MSPs mode for two kinds of biaxial anisotropic media. The dispersion equation suggests the requirements of μ x  < 0 < ε z , μ x μ y  > 1, and momentum conservation need to be satisfied, which guides us to design a planar biaxial magnetic metamaterials (PBMM) with two orthogonal negative permeabilities (i.e., μ x  < 0 and μ y  < 0). In addition, the results of the retrieval magnetic permeability and electric permittivity ... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5194725 Thu, 01 Sep 2011 06:12:27 +0100 5194725 http://www.medworm.com/index.php?rid=5173824&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fx76765483h8n6226%2F Abstract  Herein, we report on the interplay between structural and electronic properties in the dynamical screening processes and the excitation of collective modes in Ag/Cu(111). For the (9 × 9)-Ag/Cu(111) structure, the excitation of the two-dimensional plasmon, observed in Ag/Si(111), is forbidden by both the high corrugation of the Ag layer and the presence of the underlying metal substrate. The increase of the sp density of states at the Fermi energy induces the appearance of a broad peak at 7–8 eV assigned to a free-electron collective excitation. Content Type Journal ArticlePages 1-6DOI 10.1007/s11468-011-9285-5Authors Antonio Politano, Dipartimento di Fisica, Università degli Studi della Calabria, 87036 Rende, Italy Journal PlasmonicsOnline... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5173824 Fri, 26 Aug 2011 05:48:12 +0100 5173824 http://www.medworm.com/index.php?rid=5173825&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fx034848232tw74x8%2F We present and analyze a novel optical antenna structure in the form of a polarization multiplexed bullseye antenna with a central nanoaperture. By adjusting the parameters of two, orthogonally oriented, partial bullseye structures, the resonance response for each polarization can be tailored to a specific wavelength. Constructing these dual-polarization structures in aluminum, we predict intra-aperture intensity enhancements exceeding 20 at two independent resonance wavelengths spanning the UV–visible spectrum. Moreover, these resonances share significant intra-aperture excitation volumes. Content Type Journal ArticlePages 1-8DOI 10.1007/s11468-011-9273-9Authors Xiaojin Jiao, Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, UT 84112, USAS... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5173825 Thu, 25 Aug 2011 15:49:08 +0100 5173825 http://www.medworm.com/index.php?rid=5168736&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Ft134444336846847%2F We report on experimental and theoretical studies of plasmon-induced effects in a hybrid nanostructure composed of light-harvesting complexes and metallic nanoparticles in the form of semicontinuous silver film. The results of continuous-wave and time-resolved spectroscopy indicate that absorption of the light-harvesting complexes is strongly enhanced upon coupling with the metallic film spaced by 25 nm of a dielectric silica layer. This conclusion is corroborated by modeling, which confirms the morphology of the silver island film. Content Type Journal ArticlePages 1-7DOI 10.1007/s11468-011-9283-7Authors Nikodem Czechowski, Institute of Physics, Nicolaus Copernicus University, Grudziadzka 5/7, 87-100 Torun, PolandPiotr Nyga, Institute of Optoelectronics, Military Universit... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5168736 Tue, 23 Aug 2011 15:50:36 +0100 5168736 http://www.medworm.com/index.php?rid=5155315&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fy811036137423005%2F Abstract  Significant quenching of fluorescence from CdSe/ZnS nanocrystal quantum dots (QDs) coated with mercaptoundecanoic ligands has been realized by copper nanoparticles (NPs). (a) Static quenching in the electrostatic association between the CdSe/ZnS QDs and cetyltrimethylammonium bromide-coated Cu NPs and (b) dynamic quenching of the same nanocrystals by polyvinylpyrrolidone-coated Cu NPs were studied. In both cases, the quenching of fluorescence from the CdSe/ZnS nanocrystals is sensitive to nanomolar concentrations of the copper NPs, and the quenching efficiency increases as spectral overlap between the CdSe/ZnS emission and the copper nanoparticle absorption increases. This suggests that the observed quenching is a result of energy transfer processes. These finding... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5155315 Fri, 19 Aug 2011 05:51:02 +0100 5155315 http://www.medworm.com/index.php?rid=5155316&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Ft847312765614336%2F Abstract  We consider the formation of the surface plasmon polariton (SPP) mode in the structure with a metallic torus and a metallic flat surface separated by a dielectric medium. The energy of the wave field is mainly concentrated in the dielectric medium at the vicinity of the minimum thickness of the gap between the metallic surfaces. The dependence of the resonant frequency on parameters of the structure was determined. The strongly localized SPP mode in the transverse direction contributes to the increase in the Purcell factor that is crucial for enhancement of the spontaneous emission rate. Content Type Journal ArticlePages 1-5DOI 10.1007/s11468-011-9267-7Authors Artashes Vardanyan, Department of Radiophysics, Yerevan State University, A. Manoogian 1, Yerevan, 0... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5155316 Thu, 18 Aug 2011 05:59:14 +0100 5155316 http://www.medworm.com/index.php?rid=5155317&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fa33908u07l563084%2F Abstract  A subwavelength plasmonic laser structure based on a metal-dielectric-metal nanocavity is proposed and numerically simulated by using the finite difference time domain method with perfectly matched layer absorbing boundary condition. The nanocavity model and gain analysis are respectively given. The simulation results show that the losses within the nanocavity (including surface plasmon losses) can be compensated by the gain material and the threshold gain of the laser is about 1.5 × 103 cm−1 with the peak wavelength around 1,550 nm. The new device would be an important step toward a fully integrated surface plasmon circuits. Content Type Journal ArticlePages 1-6DOI 10.1007/s11468-011-9280-xAuthors Jia Hu Zhu, Key laboratory of Photonic Infor... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5155317 Thu, 18 Aug 2011 05:59:13 +0100 5155317 http://www.medworm.com/index.php?rid=5155318&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fk4414053206503nn%2F Abstract  Precise ablation of metals using tightly focused femtosecond laser pulses with intensities close to the damage threshold can yield sub-wavelength, nanometer-sized holes or craters. These structures in metals can exhibit plasmonic effects, thereby affecting the interactions involved. We numerically simulate light propagation inside such holes and model the ablation process. We show that surface plasmon resonances can be excited at near-infrared and visible wavelengths. At resonance wavelengths, significant enhancement of aspect ratio is possible. Our results show that plasmonic effects are essential for the understanding of precision laser processing of metals, and they can be exploited to significantly enhance the performance of laser micro- and nano-machining. ... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5155318 Wed, 17 Aug 2011 06:04:43 +0100 5155318 http://www.medworm.com/index.php?rid=5155319&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F3891646283757433%2F In this report, the preparation of Au–Ag core–shell structures obtained by coating the Au surface with peptide and Raman reporter molecule and depositing an Ag layer on it is reported. The prepared Au–Ag NPs are tested for their surface-enhanced Raman scattering (SERS) performance. The negatively charged peptides with three different lengths, which are 3 (P1), 15 (P2), and 21 (P3) amino acid long, were chemically attached to 13 nm AuNPs along with Raman reporter molecule, carboxytetramethylrhodamine, and these modified AuNPs were coated with three different shell thickness of Ag metal. The prepared Au–Ag NPs were tested for their SERS performance and found that the Au–Ag NPs prepared with P2 and thickest shell performs best as SERS label. Content Type Journal Arti... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5155319 Wed, 17 Aug 2011 06:04:42 +0100 5155319 http://www.medworm.com/index.php?rid=5155320&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F38u0m8676jw3r37q%2F Abstract  H-shaped resonant optical antennas are proposed by adding resonant strips at the ends of arms of short dipole antennas. Numerical simulations using finite-difference time-domain method show that the H-shaped antennas present greater electric field enhancement compared with optical dipole antennas at the same resonant wavelength. The slot coupling between the two arms also results in a smaller full width at half maximum of the scattering spectra. Two field-enhancing mechanisms are found to decide the resonant properties of the H-shaped antennas. The influence of the geometry is studied. Content Type Journal ArticlePages 1-5DOI 10.1007/s11468-011-9268-6Authors Xu Han, State Key Laboratory for Mesoscopic Physics and Department of Physics, Peking University, Beij... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5155320 Tue, 16 Aug 2011 06:19:30 +0100 5155320 http://www.medworm.com/index.php?rid=5137574&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fp6ul47u45277155l%2F Abstract  Extraordinary transmission through a metal film with an array of subwavelength holes (mesh) can be modeled effectively using three-dimensional finite difference time domain (3D-FDTD) calculations. A simple 3D-FDTD model, where a plane wave of light at perpendicular incidence with no angular spread interacts with a periodic repeating mesh, models the shape and location of the transmission resonance peaks qualitatively but not quantitatively. The simple 3D-FDTD model gives peaks that are tall, sharp, and red-shifted compared to experimental measurements using a benchtop Fourier transform infrared (FTIR) spectrometer. It was discovered that the simple model does not account accurately for diffraction order scattering by the mesh or the angular spread of the actual FT... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5137574 Sat, 13 Aug 2011 06:10:59 +0100 5137574 http://www.medworm.com/index.php?rid=5137575&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fx810580q21kk6512%2F Abstract  In the coherently trapped populations of a four-level atom, we demonstrated the quantum beats with different mechanism, which originate from the interference between transition channels with different dipole moments. The beat frequency is determined by the intrinsic atomic parameters, i.e., the spacing of upper levels and ratio of dipole moments. The resonant plasmonic nanoantenna, as a candidate for the creation of anisotropic vacuum, was proposed to achieve the nanoscale realization of the quantum beats, spontaneous emission cancellation, and Rabi oscillation in two-photon correlations through the enhanced near-field and modified decay rates. Content Type Journal ArticlePages 1-6DOI 10.1007/s11468-011-9272-xAuthors Ying Gu, State Key Laboratory for Mesosco... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5137575 Sat, 13 Aug 2011 06:10:58 +0100 5137575 http://www.medworm.com/index.php?rid=5129811&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fm6kh835537332l44%2F Abstract  We provide both experimental and theoretical investigation on extraordinary low transmission through one-dimensional nanoslit and two-dimensional nanohole arrays on ultra-thin metal films. Unambiguous proofs demonstrate that short-range surface plasmon polaritons play a key role leading to this novel phenomenon, which could be useful for creating new polarization filters and other integrated plasmonic components. Content Type Journal ArticlePages 1-6DOI 10.1007/s11468-011-9274-8Authors Qiaoqiang Gan, Electrical and Computer Engineering Department, Lehigh University, Bethlehem, PA 18015, USAWenli Bai, Electrical and Computer Engineering Department, Lehigh University, Bethlehem, PA 18015, USASuhua Jiang, Department of Materials Science, Fudan University, Shangha... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5129811 Fri, 12 Aug 2011 06:11:58 +0100 5129811 http://www.medworm.com/index.php?rid=5129812&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F53uqrwtu00jt1577%2F Abstract  Silicon nanonowires (SiNWs) were synthesized with approximately 100 nm/min by very-high-frequency plasma-enhanced chemical vapor deposition method via a vapor–liquid–solid mechanism. Pure silane gas was deposited on Au-coated silicon substrates at various radio frequency (RF) powers varied from 5 to 20 W, keeping other deposition parameters constant. Synthesized SiNWs were needle-like shape with an ultra-sharp tip diameter of about 10 nm and a length about 3 μm, which differs from the standard cylindrical nanowire produced by similar techniques. Furthermore, it was shown that the average length of nanoneedles augmented with the increase of RF power. High-resolution transition electron microscopy displayed that the nanowires were composed of... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5129812 Fri, 12 Aug 2011 06:11:57 +0100 5129812 http://www.medworm.com/index.php?rid=5129813&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Flgl2841589qq55j6%2F Abstract  In this paper, we report on luminescence and absorbance effects of Er+3:Au-doped tellurite glasses synthesized by a melting-quenching and heat treatment technique. After annealing times of 2.5, 5.0, 7.5, and 10.0 h, at 300 °C, the gold nanoparticles (GNP) effects on the Er+3 are verified from luminescence spectra and the corresponding levels lifetime. The localized surface plasmon resonance around 800 nm produced a maximum fluorescence enhancement for the band ranging from 800 to 840 nm, corresponding to the transitions 4H11/2 → 4I13/2 (805 nm) and 4S3/2 → 4I13/2 (840 nm), with annealing time till 7.5 h. The measured lifetime of the levels 4H11/2 and 4S3/2 confirmed the lifetime reduction due to the energy transfer from... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5129813 Fri, 12 Aug 2011 06:11:56 +0100 5129813 http://www.medworm.com/index.php?rid=5124292&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F5307689v86874137%2F Abstract  A facile procedure to fabricate large arrays of highly ordered metal nanocups, 250 nm in diameter, is reported. The nanostructure is generated from periodic photoresist templates created by holographic laser interference lithography. A subsequent gold deposition and a peeling-off step respectively results in a large area of hemispherical nano-indentations or nanocups. A wide range of coating materials can be used, and the dimensions and periodicity of the structure are easily controlled. The structure’s ability to support localized surface plasmon polaritons was manifested by reflectance spectroscopy. A good correlation between experimental data and calculated data was observed. Content Type Journal ArticlePages 1-4DOI 10.1007/s11468-011-9258-8Authors ... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5124292 Tue, 09 Aug 2011 05:45:20 +0100 5124292 http://www.medworm.com/index.php?rid=5124293&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F5513586gj35221j6%2F Abstract  Using the finite difference time-domain method, we present a comprehensive numerical investigation of a branch-shaped filter based on the metal-insulator-metal (MIM) waveguide. The results show that several passbands and stopbands appear in the transmission spectra, which are resulted by the phase differences between the surface plasmon polaritons (SPPs) propagating along the straight waveguide and the SPPs resonating in the circuit formed by the branch and the straight waveguide. The effects of the structural parameters of the branch-shaped filters on their transmission properties are also studied. These results not only present an alternative plasmonic filter for the MIM waveguides but also help us to understand the transmission properties of the circuit-shaped ... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5124293 Mon, 08 Aug 2011 19:48:56 +0100 5124293 http://www.medworm.com/index.php?rid=5124295&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fc502348v41lpx433%2F Abstract  The optical response of graded-index spherical metallic nanoparticles is studied in the modified long wavelength approximation with electrodynamic effects accounted for to the lowest order of the inverse of the wavelength. An effective-medium approach is adopted which leads to the conclusion that the first-order dynamical effects will enter mainly via the polarizability and not the effective dielectric function of the system. Numerical studies using various graded Drude functions show that these effects are not only significant for particles of large sizes but can also be appreciable for smaller particles with varying index profile. Content Type Journal ArticlePages 1-6DOI 10.1007/s11468-011-9269-5Authors Hung Yi Chung, Department of Physics, National Taiwan... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5124295 Mon, 08 Aug 2011 19:48:55 +0100 5124295 http://www.medworm.com/index.php?rid=5124294&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F44w73605w664p262%2F Abstract  Commercially available digital versatile discs (DVDs) contain a silver-coated spiral distribution of rectangular-shaped grooves (AgDVD): for the first time, they have been used to produce surface-enhanced Raman scattering (SERS) substrates by electrochemical deposition of silver nanoparticles (AgNPs@AgDVD). The overall procedure only requires cheap and widely available materials and can be easily accomplished. Scanning electron microscopy images of AgNPs@AgDVD revealed that small AgNPs (average diameter about 15 nm) are present within the valleys of AgDVD, whereas over the ridges, the AgNPs are bigger, more densely packed and with a dendrite-like morphology somewhere. The SERS properties of these substrates have been studied in terms of the enhancement factor... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5124294 Mon, 08 Aug 2011 19:48:55 +0100 5124294 http://www.medworm.com/index.php?rid=5124296&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fbw1l81u3r6257514%2F Abstract  Optical transmission properties of multilayered ultra-thin metal gratings are numerically studied. The transmission spectrum has a broad stop-band with extremely low transmittance compared to that of a single-layer one for TM polarization. The stop-band is shown to be formed by multiple-interference tunneling and various plasmon resonance processes in ultra-thin-metal and dielectric multilayers. That is on the transmission background of non-apertured metal/dielectric multilayer structures that have low transmission in the long-wavelength range due to destructive multiple-interference tunneling, the transmission is further suppressed in the stop-band by plasmon resonances in the top metal/dielectric layers, e.g., the anti-symmetric bound surface plasmon mode in the... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5124296 Mon, 08 Aug 2011 19:48:51 +0100 5124296 http://www.medworm.com/index.php?rid=5124297&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F2g0r8375p7542630%2F Abstract  A design of a TiO2 core and Ag shell spherical nanoparticle is theoretically presented. The nanoparticles display double dipole plasmonic resonance peaks: one located at the ultraviolet range, the other is widely tunable from the visible to the near infrared region. The tunability can be easily controlled by varying the sizes of the core and the shell. The near field patterns of the double plasmonic resonance peaks are analyzed, and the dipole resonance modes for those two peaks are confirmed for the suitable core–shell sizes. Content Type Journal ArticlePages 1-6DOI 10.1007/s11468-011-9264-xAuthors Quanshui Li, Department of Mechanical, Aerospace and Biomedical Engineering University of Tennessee, Knoxville, TN 37996, USAZhili Zhang, Department of Mechanic... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5124297 Mon, 08 Aug 2011 19:48:50 +0100 5124297 http://www.medworm.com/index.php?rid=5124298&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fhr3x181106515371%2F Abstract  All-optical plasmonic switches based on a novel coupled nano-disk cavity configuration containing nonlinear material are proposed and numerically investigated. The finite difference time domain simulation results reveal that the single-disk plasmonic structure can operate as an “on–off” switch with the presence/absence of pumping light. We also demonstrate that the proposed T-shaped plasmonic structure with two disk cavities can switch signal light from one port to another under an optical pumping light, functioning as a bidirectional switch. The proposed nano-disk cavity plasmonic switches have many advantages such as compact size, requirement of low pumping light intensity, and ultra-fast switching time at a femto-second scale, which are promising for futu... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5124298 Mon, 08 Aug 2011 19:48:49 +0100 5124298 http://www.medworm.com/index.php?rid=5116921&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fd8n0m20w3q31g7m7%2F Abstract  We have investigated the polarization-dependent surface-enhanced Raman scattering (SERS) of an individual Ag nanowire (AgNW) dimer, which contains two parallel closely packed AgNWs with very different lengths. Similar cos2 θ dependence of signal intensities with respect to the polarization angle θ of the incident laser was observed from the dimeric part and the parts of the body as well as the tip of the longer AgNW. The dimeric part was demonstrated to exhibit the strongest SERS effect. The results agree well with our numerical simulations of the electric field distributions using finite element method. The SERS enhancement mechanisms at different parts of the dimer were also discussed which are different in origin. Content Type Journal ArticlePages 1-6DOI ... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5116921 Sat, 06 Aug 2011 05:54:54 +0100 5116921 http://www.medworm.com/index.php?rid=5105888&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F4226136476654m11%2F Abstract  A low-cost and effective surface-enhanced Raman scattering (SERS) substrate consisting of aligned gold nanorods is obtained by stretching the poly(vinyl alcohol) nanorods composite film doped with the probe molecule. The SERS intensity of characteristic vibrational band of the probe is observed obviously dependent on the angle (θ) between incident polarization and major axis of nanorod. The relationship between them manifests a cos2 θ dependence. The result is illustrated from both the localized field enhancement and optical antenna effect of gold nanorod. The finite element method calculation is also performed to further confirm the conclusion. Content Type Journal ArticlePages 1-5DOI 10.1007/s11468-011-9265-9Authors Jun Tao, Department of Optics and Optic... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5105888 Fri, 05 Aug 2011 05:55:54 +0100 5105888 http://www.medworm.com/index.php?rid=5105889&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fk4g7mj3x50788717%2F Abstract  Confinement of exciton–polaritons using ridge–trench structures filled with fluorescent dye materials was investigated on the basis of geometrical analysis as well as plasmonic behavior analysis. It was found that the photoluminescence intensity of the dye increased significantly in the trench than on the ridge due to geometry confinement. However, with silver layer deposited between the ridge–trench structure on Si substrate and the fluorescence dye, apparent photoluminescence peaks due to surface plasmon resonance centered at 360 nm (3.45 eV) were generated while the photoluminescence peaks of the dye materials centered at 580 nm (2.14 eV) quenched in the trench. Competition of spontaneous emission coupled into external electromagnetic ... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5105889 Fri, 05 Aug 2011 05:55:52 +0100 5105889 http://www.medworm.com/index.php?rid=5105890&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fe640636392q72076%2F Abstract  Nanocomposite thin films consisting of Cu nanoparticles embedded in silica matrix were synthesized by atom beam co-sputtering technique. Plasmonic, optical, and structural properties of the nanocomposite films were investigated by using ultraviolet (UV)–visible absorption spectroscopy, nonlinear optical transmission, X-ray diffraction (XRD), and low-frequency Raman scattering. UV–visible absorption studies revealed the surface plasmon resonance absorption at 564 nm which showed a red shift with increase in Cu fraction. XRD results together with surface plasmon resonance absorption confirmed the presence of Cu nanoparticles of different size. Low-frequency Raman studies of nanocomposite films revealed breathing modes in Cu nanoparticles. Nanocomposites wit... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5105890 Thu, 04 Aug 2011 15:31:34 +0100 5105890 http://www.medworm.com/index.php?rid=5093980&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F4j4u64648r151423%2F Abstract  For the first time, we report remote excitation polarization-dependent surface photochemical reaction by plasmonic waveguide. Remote excitation polarization-dependent surface-enhanced Raman scattering (SERS) spectra indicate a surface photochemical reaction that p-aminothiophenol is converted to p,p′-dimercaptoazobenzene (DMAB) induced by the plasmonic waveguide. Surface plasmon polaritons generated at the end of a silver nanowire can propagate efficiently along the nanowire, and be coupled by nanoparticles near the nanowire as a nanoantenna. Massive electromagnetic enhancement is generated in the nanogap between the nanowire and the nanoparticles. The remote excitation polarization-dependent SERS spectra can be obtained experimentally in the nanogaps; furthermo... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5093980 Mon, 01 Aug 2011 05:32:19 +0100 5093980 http://www.medworm.com/index.php?rid=5061303&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fw2701r4254512472%2F Abstract  The surface plasmon resonances of silver nanoshell particles are studied by Green’s function. The nanoshell system of plasmon resonances results from the coupling of the inner and outer shell surface plasmon. The shift of the nanoshell plasmon resonances wavelength is plotted against with different dielectric environments, several different dielectric cores, the ratio of the inner and outer radius, and also its assemblies. The results show that a red- and blue-shifted localized surface plasmon can be tuned over an extended wavelength range by varying dielectric environments, the dielectric constants and the radius of nanoshell core respectively. In addition, the separation distances, the distribution of electrical field intensity, the incident directions and its... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5061303 Fri, 22 Jul 2011 16:58:59 +0100 5061303 http://www.medworm.com/index.php?rid=5061304&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F83n48t8331jt0203%2F Abstract  Based on a metal-dielectric-metal (MDM) plasmonic waveguide side coupled with a single cavity, we rebuild such resonator system by cascading double side-coupled cavities to obtain flat-top reflection response over a frequency bandwidth. The increased coherent scattering path provides an additional freedom to engineer the complex interference between the cavity modes and the waveguide mode. By decomposing the compound cavity modes into two decoupled resonances, we analyze the conditions to realize flat-top reflection response. The physics behind the flat-top reflection characteristics is found to be originated from the interference interaction between the two cavities through examining the cavity excitations and the reflected power response. Temporal coupled-mode t... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5061304 Tue, 19 Jul 2011 06:39:40 +0100 5061304 http://www.medworm.com/index.php?rid=5061305&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fp54382365601l266%2F We present a theoretical study on plasmonic enhancement of molecular fluorescence near a nanocomposite, Ag nanoshell (Ag-NS) coated by a gain medium of molecule-doped SiO2 layer. We use an average enhancement factor (AEF), which considers contributions from all possible orientations and locations of molecules in the silica layer to estimate the overall performance of Ag-NS@SiO2 at specific excitation and emission wavelengths. Our results on the AEF reveal that Ag-NS@SiO2 is a dual-band enhancer on the spontaneous emission of the gain medium; one is a narrowband in a shorter wavelength regime (quadrupole mode) and the other is a broadband in a longer wavelength regime (dipole mode). These two bands are tunable by adjusting the core size and the thickness of the Ag shell. Due to this mer... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5061305 Tue, 19 Jul 2011 06:39:37 +0100 5061305 http://www.medworm.com/index.php?rid=5048073&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fp7728w0766nw246k%2F We report a strategy to improve two types of the figure of merit (FOM and FOM*) of the refractive index sensitivity of a gold nanobar array localized surface plasmon resonance (LSPR) biosensor by simply placing it close to a thin gold film with a dielectric spacer. The thickness of the dielectric spacer determines the plasmon coupling strength between the gold nanobars and the gold film and consequently the FOM and FOM* of the biosensor. From our calculations, when the spacer thickness is 20 nm, the FOM and FOM* reach maximal (4.68 and 310, respectively) and the sensitivity remains at a high value of 600 nm per refractive index unit. This biosensor scheme is practically realizable, and this strategy is also potentially applicable to the LSPR biosensors with other geometries... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5048073 Fri, 15 Jul 2011 05:54:14 +0100 5048073 http://www.medworm.com/index.php?rid=5048074&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fx864p10810204475%2F Abstract  Propagating surface plasmon (PSP) excitation, based on the total internal reflection configuration, was introduced into the nanoparticle (NP)-plane junction Raman spectroscopy. Experimental results demonstrated that silver nanospheres within the propagation region of PSP are effectively activated and detected by CCD camera due to their impressive Raman enhancement, which presents around 20 times improvement compared with the conventional NP-induced PSP/LSP co-enhanced Raman spectroscopy. This impressive Raman enhancement along with its high reproducibility of NP-plane junctions makes our configuration an attractive candidature for the PSP-assisted gap-mode surface-enhancement Raman spectroscopy and tip-enhanced Raman spectroscopy. Content Type Journal ArticleP... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5048074 Fri, 15 Jul 2011 05:54:13 +0100 5048074 http://www.medworm.com/index.php?rid=5035338&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Frt4x6w3q77879530%2F We present a new method enabling simultaneous synthesis and deposition of gold micro-flowers (AuMFs) on solid substrates in a one-pot process that uses two reagents, auric acid and hydroxylamine hydrochloride, in aqueous reaction mixture. The AuMFs deposited onto the substrate form mechanically stable gold layer of expanded nanostructured surface. The morphology of the AuMFs depends on and can be controlled by the composition of the reaction solution as well as by the reaction time. The nanostructured metallic layers obtained with our method are employed as efficient platforms for chemical and biological sensing based on surface-enhanced Raman spectroscopy (SERS). SERS spectra recorded by such platforms for p-mercaptobenzoic acid and phage lambda exhibit enhancement factors above 106 ... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5035338 Wed, 13 Jul 2011 05:58:56 +0100 5035338 http://www.medworm.com/index.php?rid=5035337&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F278t732074010855%2F Abstract  We fabricated nanostructured Pt thin films with two different morphologies and studied their effects on the Raman spectrum of rhodamine 6G. The syntheses were achieved by templating mesoporous silica thin films which are characterized by 8-nm-sized pore channels and 3–4-nm-thick walls in two different orientations of the channels. Therefore, the resultant nanostructured Pt thin films are composed of Pt nanorods of 8 nm in diameter vertically standing in one morphology and horizontally lying in the other. The latter produced stronger Raman signals than the former. Simulations based the discrete-dipole approximation on model nanostructures showed that the horizontally lying nanorods produce stronger local electromagnetic field than the vertically standing one... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5035337 Wed, 13 Jul 2011 05:58:56 +0100 5035337 http://www.medworm.com/index.php?rid=5035339&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F0854683026754j4r%2F Abstract  A gold film with subwavelength nanoholes on a glass substrate was fabricated through electron beam lithography and its extraordinary optical transmission (EOT) was characterized. By applying a liquid crystal overlayer to the gold film, its EOT can be further enhanced by ~11% due to the refractive index matching of the dielectric media on its two sides. By controlling the alignment of the liquid crystal molecules, a highly reversible and reproducible tuning of the transmission peak in both intensity and position is demonstrated. Content Type Journal ArticlePages 1-6DOI 10.1007/s11468-011-9248-xAuthors Y. J. Liu, Institute of Materials Research and Engineering, Agency for Science Technology and Research (A*STAR), 3 Research Link, Singapore, 117602 Republic of S... Plasmonics journals http://www.medworm.com/rss/comments.php?id=5035339 Tue, 12 Jul 2011 06:08:08 +0100 5035339 http://www.medworm.com/index.php?rid=4951175&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fa181lwm2746r7k30%2F Abstract  A new plasmonic structure based on bimetallic layer is proposed. We analyze the structure and show that bimetallic film plays a crucial role in the management of surface plasmons. The roll of the buffer is discussed, as well. Up to three surface plasmons can be excited simultaneously in the structure. Two of plasmons can be used for two-plasmon spectroscopy. The third plasmon can be used for controlling the temperature of the structure. Content Type Journal ArticlePages 1-8DOI 10.1007/s11468-011-9246-zAuthors Georgi Dyankov, Institute of Nanomaterials and Nanotechnology (INANOTECH), Moroccan Association for Science, Innovation and Research (MAScIR), Av. de l’Arme Royale, Madinat El Irfane, 10100 Rabat, MoroccoMohsin Zekriti, Institute of Nanomaterials and Na... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4951175 Tue, 14 Jun 2011 05:50:18 +0100 4951175 http://www.medworm.com/index.php?rid=4931943&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fa38l61v182p785x6%2F Abstract  A qualitative model explaining the extraordinary optical transmission of terahertz (THz) radiation through two-dimensional periodic arrays of subwavelength apertures is presented. Systematic terahertz time-domain spectroscopy studies have been undertaken to investigate the combined effects of the lattice arrangement, aperture shape, area and aspect ratio on the transmission properties of electroformed copper arrays. The extensive results presented provide a unified example of how aperture geometry dictates SPP activity. The novel fabrication method creates exemplary peak resonances, allowing the onset of surface plasmon polariton (SPP) decoupling to be distinguished from direct transmission. Furthermore, we provide the first evidence as to how the temporal propert... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4931943 Sat, 11 Jun 2011 06:34:40 +0100 4931943 http://www.medworm.com/index.php?rid=4931944&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fj711855506v4lx52%2F Abstract  We propose to use the compressed or stretched hyperbola for an efficient description of the plasmon resonance shift as a function of the gap between proximal nanoparticles in arrays of gold pairs. This function overcomes the limitation of describing this behavior by the well-known exponential function as it accounts for the near-field coupling and the far-field radiative coupling between particles . It has the advantage of mathematical simplicity with one dimensionless additional parameter compared to a simple exponential decay. We suggest that this parameter may be the signature of the grating effects. Most importantly this function works well in a wide variety of surrounding media and for nanostructures with arbitrary shapes. We expect that this function is an e... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4931944 Fri, 10 Jun 2011 06:28:34 +0100 4931944 http://www.medworm.com/index.php?rid=4931945&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F28863886p6772511%2F Abstract  We numerically report on first realization of near-field interaction and localized surface Plasmon resonance of a pair of silver-shell nanospheres with different dielectric holes embedded in a dielectric substrate using finite element method. An electromagnetic mode different from the solid case of the same volume is excited inside and outside the shell surface, resulting in an intensity enhancement in a gap of particle pair surrounding the particle–substrate interface. We find that the embedded depth of the nanoparticles pair in a substrate will influence the position of the localized fields which is confined in the gap. Besides, the near-field intensity becomes less intense and the spectrum of peak resonances red-shifted as the index difference of interface an... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4931945 Fri, 10 Jun 2011 06:28:33 +0100 4931945 http://www.medworm.com/index.php?rid=4900985&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fa05p2423x6391143%2F Abstract  Electro-optical (EO) switches with a subwavelength device length based on metal–dielectric–metal nanocavities waveguide combined with organic EO materials have been proposed and numerically investigated. The finite difference time domain (FDTD) method with perfectly matched layer absorbing boundary condition is adopted to simulate and study their properties. The FDTD simulation results reveal that these structures filled with EO materials can realize the function of switch with low-driving voltage. The wavelength conversion switch structure might become a choice for the design of integrated architectures for optical computing and communication, especially in WDM systems in the nanoscale. Content Type Journal ArticlePages 1-8DOI 10.1007/s11468-011-9241-4Aut... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4900985 Fri, 03 Jun 2011 05:53:46 +0100 4900985 http://www.medworm.com/index.php?rid=4900986&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fq855528734870347%2F Abstract  A sub-wavelength electro-optic switch based on plasmonic T-shaped waveguide has been proposed and numerically investigated. The finite-difference time-domain simulation results reveal that the switch based on T-shaped waveguide with two U-shaped grooves can realize the function of switching single wavelength from one port to the other by an external voltage. The U-shaped structure is composed of two teeth filled with highly nonlinear organic EO material and one groove filled with 6H-SiC connecting the two teeth. The switch wavelength can be chosen by adjusting both lengths of the left and right teeth, and the switch voltage is 3.35 V for the wavelength of λ = 730 nm with the insertion loss around −2.6 dB and the extinction ratio around −20&n... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4900986 Fri, 03 Jun 2011 05:53:44 +0100 4900986 http://www.medworm.com/index.php?rid=4900987&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F42v36348w5046348%2F This article reviews the recent development in plasmonic nanolithography, which is considered as one of the most remarkable technology for next-generation nanolithography. Nanolithography experiments were highlighted on the basis of SPPs effect. Three types of plasmonic nanolithography methods: contact nanolithography, planar lens imaging nanolithography, and direct writing nanolithography were reviewed in detail, and their advantages and shortages are analyzed and compared, respectively. Finally, the development trend of plasmonic nanolithography is suggested. Content Type Journal ArticlePages 1-16DOI 10.1007/s11468-011-9237-0Authors Zhihua Xie, Opto-electronic Technology Center, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, ... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4900987 Mon, 30 May 2011 16:49:42 +0100 4900987 http://www.medworm.com/index.php?rid=4900988&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fk81073804w4l3327%2F Abstract  Bowtie nanoantenna arrays were fabricated using plasma-assisted nanosphere lithography. The gap of each bowtie nanoantenna was precisely controlled by tuning the oxygen plasma treatment time, and gap distance as small as 30 nm was successfully fabricated. The occurrence of plasmon coupling and the functionality of the bowtie nanoantenna arrays were experimentally and theoretically verified. The plasma treatments help to change the size and gap distance of the nanoparticle arrays to match a specific surface plasmon resonance wavelength. The fabricated nanoantenna array covered a large area (∼1 cm2) and was suitable for large-scale fabrication with simple scale-up of the fabrication instruments, which should lead to novel new applications. Content Ty... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4900988 Mon, 30 May 2011 16:49:38 +0100 4900988 http://www.medworm.com/index.php?rid=4900989&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fb143556421721471%2F Abstract  The key challenge of the plasmonic waveguide is to achieve simultaneously both the long propagation length and high confinement. The hybrid dielectric-loaded plasmonic waveguide consists of a SiO2 stripe sandwiched between a Si-nanowire and a silver film and thus promises as a best candidate to overcome this challenge. We propose to exploit this unique property of this structure to design different high-efficient silicon-based plasmonic components including waveguide, power splitter, and wavelength-selective ring resonator. As a result, the proposed power splitter with a waveguide cross section (λ 2/60) and a strong mode confinement area (~λ 2/240) features a low power transmission loss (<0.4 dB) at the optimal arm length of 4 μm with respect to di... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4900989 Mon, 30 May 2011 16:49:37 +0100 4900989 http://www.medworm.com/index.php?rid=4900990&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fj572r27505646107%2F Abstract  A nanoscale surface plasmon all-optical diode is proposed based on a plasmonic slot waveguide having an asymmetric plasmonic grating in the center. The asymmetric configuration of the plasmonic grating and the unique dispersion relations of the plasmonic slot waveguide ensure the nonreciprocal transmission properties. High transmittance contrast ratio of 1,150 is achieved theoretically. The performance of the surface plasmon all-optical diode does not have any high power requirement. This may open a new way for the study of integrated photonic devices based on surface plasmons. Content Type Journal ArticlePages 1-6DOI 10.1007/s11468-011-9243-2Authors Xiaoyong Hu, State Key Laboratory for Mesoscopic Physics and Department of Physics, Peking University, Beijing... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4900990 Mon, 30 May 2011 16:49:33 +0100 4900990 http://www.medworm.com/index.php?rid=4900991&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fhh10376h84664h54%2F Abstract  A near-field coupling method for studying propagation properties of surface plasmon polariton (SPP) in subwavelength dielectric-loaded SPP waveguides (DLSPPWs) is presented. In this method, a tapered fiber probe is employed to generate a nanometer optical spot. When this spot is near the entrance of the DLSPPW with its polarization parallel to the waveguide, a strong guiding wave is observed by a leakage radiation microscope. For DLSPPWs with a dielectric height of about 600 nm, we observed SPP waves with zigzag propagation patterns at 650 nm wavelength. Such zigzag propagation results in a great reduction of propagation loss. In addition, the zigzag wave has a strong optical confinement. The bending loss for an L-bend DLSPPW is only about 0.4 dB. ... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4900991 Mon, 23 May 2011 05:34:55 +0100 4900991 http://www.medworm.com/index.php?rid=4839457&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fv7jk0w9682v17j46%2F Abstract  We have demonstrated that plasma treatments of silver nanoparticles bring about blueshift and narrowing in their localized surface plasmon resonance. Surface-enhanced Raman scattering analysis revealed that hydrocarbons adsorbed on silver surfaces were removed effectively by plasma exposure. It was found that the decrease in Raman line intensity for hydrocarbons was correlated well with the blueshift. Our findings indicate that one of the most important factors for remarkable differences in plasmon resonance wavelengths and line widths reported for the silver nanoparticles supported on substrates between most of the experimental data and calculations by Mie’s theory is due to the impurity adsorption on silver surfaces. Content Type Journal ArticlePages 1-5DO... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4839457 Mon, 16 May 2011 08:42:41 +0100 4839457 http://www.medworm.com/index.php?rid=4839458&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F56630u8744l66hp1%2F Abstract  Because of the interaction between dipole resonances of the inner gold sphere and the outer gold shell, gold-dielectric-gold multishells with sub-50 nm diameter may at most have three hybridization modes of surface plasmon resonance (SPR). Theoretical calculations based on quasi-static theory indicate that there are blending and splitting of SPR bands in the absorption spectra, which makes the number of absorption peak tunable by changing the radius of inserted gold sphere, thickness of gold shell, dielectric constant of middle dielectric shell or outer environment. The two absorption peaks at longer wavelength, which correspond to the hybridization from the bonding shell plasmon and the sphere plasmon, are usually intense and well tunable. The absorption pea... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4839458 Sat, 14 May 2011 15:57:09 +0100 4839458 http://www.medworm.com/index.php?rid=4839459&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fp9p3g97390316720%2F Abstract  The reduction of average extinction cross section of a localized surface plasmon (LSP) resonance mode under the random orientation condition of Au nanoring (NRI) distribution is first numerically demonstrated. The reduction range depends on the geometry symmetry property of the electron oscillation axis in the LSP resonance mode. Then, by increasing the ring height, an optimized Au NRI geometry is designed to make the resonance wavelengths of its cross-ring dipole mode and axial dipole mode the same. In such an Au NRI, a few higher-order axial LSP modes are discovered. Also, under the condition of random orientation distribution, the ranges of extinction, scattering, and absorption cross section reductions from the corresponding maximum levels of optimized excitat... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4839459 Thu, 12 May 2011 16:44:15 +0100 4839459 http://www.medworm.com/index.php?rid=4819471&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F8442n4r7031144t8%2F Abstract  We performed numerical investigations of surface plasmon excitation and propagation in structures made of a photochromic polymer layer deposited over a metal surface using the finite-difference time-domain method. We investigated the process of light coupling into surface plasmon polariton excitation using surface relief gratings formed on the top of a polymer layer and compared it with the coupling via rectangular ridges grating made directly in the metal layer. We also performed preliminary studies on the influence of refractive index change of photochromic polymer on surface plasmon polariton propagation conditions. Content Type Journal ArticlePages 1-6DOI 10.1007/s11468-011-9234-3Authors Pawel Karpinski, Institute of Physical and Theoretical Chemistry, Wr... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4819471 Wed, 11 May 2011 05:51:35 +0100 4819471 http://www.medworm.com/index.php?rid=4722862&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fn36763t23pm48241%2F Abstract  Nanoparticle technology plays a key role in providing opportunities and possibilities for the development of new generation of sensing tools. The targeted sensing of selective biomolecules using functionalized gold nanoparticles (Au NPs) has become a major research thrust in the last decade. Au NP-based sensors are expected to change the very foundations of sensing and detecting biomolecules. In this review, we will discuss the use of surface functionalized Au NPs for smart sensor fabrication leading to detection of specific biomolecules and heavy metal ions. Content Type Journal ArticlePages 1-16DOI 10.1007/s11468-011-9228-1Authors Shuwen Zeng, School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, 639798 SingaporeKen-T... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4722862 Thu, 14 Apr 2011 16:58:29 +0100 4722862 http://www.medworm.com/index.php?rid=4722863&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fm582710635u17r84%2F Abstract  We investigated the plasmonic modes in a two-dimensional quasicrystalline array of metal nanoparticles. The polarization of the modes is in the array plane. A simplified eigen-decomposition method is presented with the help of rotational symmetry. Two kinds of anti-phase ring modes with radial and tangential polarizations are of highest spatial localizations among all of plasmonic modes. For the leaky characteristic of the anti-phase ring modes, the highest fidelity mode in the quasicrystalline array is found to be tangential polarized mode, whereas normal-to-plane polarized mode in the circular ring. The leaky characteristics and spatial localizations of other plasmonic modes are also studied, for example, collective vortex mode that may be a candidate to form ne... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4722863 Thu, 14 Apr 2011 16:58:28 +0100 4722863 http://www.medworm.com/index.php?rid=4692390&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F506k54446tw55558%2F Abstract  Gold nanoslit arrays have multiple resonances due to localized plasmons, Bloch wave surface plasmon polaritons, and Wood’s anomaly. Different structures result in different resonances and affect the detection sensitivity of the nanoslits. We systematically compared different structure parameters such as period, slit widths, and gold film thickness by using a spectral integration method. The experimental results show the detection sensitivity had an optimal value for a 500-nm period and 130-nm-thick nanoslits. Moreover, the sensitivity increases with the decrease of the slit widths. It was improved about three times when the size was reduced from 230 to 56 nm. The optimized structure can achieve a detection limit of 5 × 10−6 refractive index unit when ... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4692390 Tue, 05 Apr 2011 16:56:34 +0100 4692390 http://www.medworm.com/index.php?rid=4692389&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F513585788l77m335%2F Abstract  We numerically study the extraordinary optical transmission of a plasmonic structure that combines a circular nanoantenna and a vertical annular nanoslit etched into a gold film under radially polarized illumination. The nanoantenna collects the incident field and localizes it in a horizontal Fabry-Pérot cavity over the gold film. The vertical nanoslit positioned at the maximal field in the horizontal cavity couples the localized field and facilitates its transmission to the free space. Due to the symmetry matching between the structure and the illumination polarization, surface plasmons can be excited effectively and enhance the transmission. Through optimizing the structure parameters, the transmission efficiency can be greatly enhanced by 225 times for a reson... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4692389 Tue, 05 Apr 2011 16:56:34 +0100 4692389 http://www.medworm.com/index.php?rid=4692391&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fl62u32u16g0v13p4%2F Abstract  In this paper, we use the parameter retrieval method together with an analytical effective medium approach to design a well-performed invisible cloak, which is based on an empirical revised version of the reduced cloak. The designed cloak can be implemented by silver nanowires with elliptical cross sections embedded in a polymethyl methacrylate host. This cloak is numerically proved to be robust for both the inner hidden object as well as incoming detecting waves and is much simpler, thus easier to manufacture when compared with the earlier one proposed by Cai et al. (Nat Photon 1: 224, 2007). Content Type Journal ArticlePages 1-5DOI 10.1007/s11468-011-9226-3Authors Yangbo Xie, School of Physical Science and Technology, Soochow University, Suzhou, Jiangsu 215... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4692391 Tue, 05 Apr 2011 16:56:33 +0100 4692391 http://www.medworm.com/index.php?rid=4682655&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F14534674u469420p%2F Abstract  The plasmonic interaction between silver nano-cubes and a silver ground plane with and without a dielectric spacer is studied for surface-enhanced Raman scattering (SERS) for rhodamine 6G (R6G) molecules absorbed onto the silver nano-cubes. Experimental results show that the composite substrates made from silver nano-cubes and the silver ground plane produce a stronger SERS signal than by the cubes alone, due to the plasmonic interaction between the cubes and the film. Numerical simulation is used to verify the plasmonic enhancement of the composite substrate and is consistent with the experimental results. The lowest concentration of R6G molecules which can be detected with the composite substrate is about 10−11 M with our setup. Content Type Journal A... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4682655 Fri, 01 Apr 2011 05:43:49 +0100 4682655 http://www.medworm.com/index.php?rid=4630772&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fq443571u278p2u02%2F Abstract  Linear clusters made by tightly connecting two or more metallic nanoparticles have new types of surface plasmon resonances as compared with isolated nanoparticles. These new resonances are sensitive to the size of the junction and to the number of interconnected particles and are described by eigenmodes of a boundary integral equation. This formulation allows effective separation of geometric and shape contribution from electric properties of the constituents. Results for particles covered by a thin shell are also provided highlighting ultrasensitive sensing applications. The present analysis sheds a new light on the interpretation of recent experiments. Content Type Journal ArticlePages 1-6DOI 10.1007/s11468-011-9218-3Authors Titus Sandu, International Cent... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4630772 Mon, 21 Mar 2011 19:04:22 +0100 4630772 http://www.medworm.com/index.php?rid=4630774&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fpl6450182775lq3r%2F Abstract  In this work, we show theoretical results of the behaviour of the extinction cross section as a function of the incident wavelength for metallic nanotubes (Nts) with a 2D core–shell structure. To calculate the optical response of the gold, silver and cooper system, an exact integral formalism is implemented. The method is based on Green’s integral theorem, and it allows us to compute the electromagnetic field at any point in space. For a correct description of the constitutive parameters of the metallic shell, we introduce a corrective model for the dielectric function in terms of the shell thickness in the range 1 to 10 nm. In particular, we investigate the features of surface plasmons in metallic Nts, and in the cases of Au and Cu, the mechanisms of the... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4630774 Mon, 21 Mar 2011 19:04:18 +0100 4630774 http://www.medworm.com/index.php?rid=4630773&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fyhx722311854w425%2F Abstract  Here, we report for the first time the synthesis of bismuth-coated silver nanoparticles in dichroic bismuth glass nanocomposites by a novel and simple one-step melt quench technique without using any external reducing agent. The metallic silver nanoparticles (Ag NPs) were generated first, and subsequently, metallic bismuth was deposited on the Ag NPs and formed a thick layer. The reduction of Bi3+ to Bio and subsequently its deposition on the Ag NPs (which were formed earlier than Bio) in the K2O–Bi2O3–B2O3 (KBB) glass system have been explained by their standard reduction potentials. The UV–vis absorption spectra show a prominent surface plasmon resonance (SPR) absorption band at 575 nm at lower concentrations (up to 0.01 wt%); three bands at 569, 6... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4630773 Mon, 21 Mar 2011 19:04:18 +0100 4630773 http://www.medworm.com/index.php?rid=4580572&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fw5m11t5271n14g24%2F Abstract  In this paper, a novel plasmonic bandgap cavity inducing the enhancement of extraordinary optical transmission is presented. Numerical simulations have been performed to model a free-standing structure made of a one-dimensional periodic arrangement of gold strips. Two different values of the lattice constant have been properly chosen to realize a double heterostructure-like cavity to accomplish extraordinary optical transmission assisted by the formation of a plasmonic bandgap in the adjacent regions. Numerical results prove the capability of this optical device to efficiently transmit input light beams with far-field transmission values close to 100% due to the excitation of surface plasmon polariton resonant modes. Content Type Journal ArticlePages 1-8DOI 10... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4580572 Fri, 11 Mar 2011 18:06:24 +0100 4580572 http://www.medworm.com/index.php?rid=4580571&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fe875686600k5616t%2F Abstract  Nanosilver of 10-nm size was prepared by the NaBH4–sodium citrate procedure, and it was modified by a single-strand DNA (ssDNA) aptamer to fabricate an AgssDNA probe for melamine. The probe was stabile at pH 7.0 Na2HPO4–NaH2PO4 buffer solutions and in the presence of 25.0 mmol/L NaCl. Upon the addition of melamine, it interacted with the probe to aggregate big clusters, which led to the resonance scattering (RS) intensity at 470 nm increasing greatly. Under the selected conditions, the increased RS intensity (ΔI 470 nm) is linear to melamine concentration in the range of 6.31–378.4 μg/L, with a regression equation of DI470 nm = 1.124c + 10.8 and a detection limit of 3.1 μg/L. The aptamer-modified nanosilver RS assay has be... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4580571 Fri, 11 Mar 2011 18:06:24 +0100 4580571 http://www.medworm.com/index.php?rid=4580573&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F50265mq6u0g32567%2F We present the novel approach to investigate properties of the 3D plasmon excited on a metal sphere. The exact plasmon field extracted from the scattered field given by Mie theory allows for a new interpretation of the 3D plasmon by four short-range-like plasmons excited and rotating simultaneously around the sphere. Content Type Journal ArticlePages 1-11DOI 10.1007/s11468-011-9223-6Authors Soulef Benghorieb, Laboratory Hubert Curien CNRS UMR 5516, University Jean Monnet, 18 rue Benoit Lauras, 42000 Saint Etienne, FranceRachida Saoudi, Laboratory Hubert Curien CNRS UMR 5516, University Jean Monnet, 18 rue Benoit Lauras, 42000 Saint Etienne, FranceAlexandre V. Tishchenko, Laboratory Hubert Curien CNRS UMR 5516, University Jean Monnet, 18 rue Benoit Lauras, 42000 Saint Etienne, Fran... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4580573 Fri, 11 Mar 2011 18:06:23 +0100 4580573 http://www.medworm.com/index.php?rid=4577735&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F265081j672472g64%2F Abstract  We obtained experimentally strong plasmon interactions between localized surface plasmon with delocalized surface plasmon polaritons in a new nanosystem of silver semishells island film arrays arranged as a closed-packing structure coupled to an adjacent thin silver film. We show that plasmon interactions for such a nanosystem exhibits two pronounced resonances and interpret the coupling in terms of Fano resonances. The higher energy resonance is identified as a symmetric hybridization mode between localized plasmon resonances in the island semishell array and surface plasmon polaritons in the metal film and while the lower energy resonance is identified as a corresponding anti-symmetric hybridization mode. Increasing the size of the particle arrays enhances and r... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4577735 Tue, 08 Mar 2011 06:45:02 +0100 4577735 http://www.medworm.com/index.php?rid=4559227&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fj737746384vpu877%2F Abstract  In this paper, the polarization effects on surface plasmon resonance (SPR) in azimuthally rotated 2D square lattice plasmonic crystal (PCL) are reported. By controlling the polarization angle (α) of the incoming beam, the SPR coupling strength can be fully enhanced when optimized α is used for different momentum lattice vectors (x-, y-axis and diagonal direction). This value can be obtained by adjusting the polarization angle until the deepest dip in SPR reflectivity spectrum can be observed. This will lead to a much easier way for determining the optimum surface plasmon polariton excitation condition for each crystal momentum in 2D PCL. Content Type Journal ArticlePages 1-8DOI 10.1007/s11468-011-9213-8Authors Husen Kartasasmita Kang, School of Materials Sci... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4559227 Fri, 04 Mar 2011 16:48:26 +0100 4559227 http://www.medworm.com/index.php?rid=4559226&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Ft0683x005576058v%2F This study investigates the optical Bloch oscillations (OBOs) in waveguide arrays that consist of alternative perfect electric conductor (PEC) layers and dielectric layers by performing both numerical simulations and theoretical analyses. In PEC dielectric waveguide arrays (PDWAs), the PEC layers are perforated with square holes to support the surface plasmon-like (SPL) modes. The relative permittivities of the dielectric layers have a constant gradient across the waveguide arrays. The OBOs in the PDWAs arise because of the excitation and coupling of the SPL modes. The ray trajectories that are predicted using Hamiltonian optics are consistent with the simulated results. When the position of incidence is fixed, the period of oscillation varies as the reciprocal of the incident freque... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4559226 Fri, 04 Mar 2011 16:48:26 +0100 4559226 http://www.medworm.com/index.php?rid=4559228&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F2qx9q25264627751%2F Abstract  Semiconductor self-assembled Ge-on-Si quantum dot structures coated with Au film were successfully employed as surface-enhanced Raman scattering (SERS) substrates to characterize ultramarine blue inorganic art pigment. To assign the bands and to reveal the enhancement mechanisms, the quantum-chemical calculations of vibration spectra of linear and cyclic model compound of SiO4 and AlO4 tetrahedra were carried out. The overtones are observed in the SERS spectra and the unharmonicity constants were estimated. The development of a series of new bands in SERS spectra of ultramarine are discussed in terms of electro-optical unharmonicity. Content Type Journal ArticlePages 1-6DOI 10.1007/s11468-011-9219-2Authors Elena Klyachkovskaya, B.I. Stepanov Institute of Phys... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4559228 Fri, 04 Mar 2011 10:49:38 +0100 4559228 http://www.medworm.com/index.php?rid=4559229&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fh312532p6852x546%2F Abstract  Silver nanoparticle (NP) precipitation in a melt-quenched aluminophosphate glass matrix has been studied and compared for 8 mol% and 4 mol% concentrations of both Ag2O and SnO dopants. The assessment is carried out by monitoring the plasmonic evolution of glass-embedded Ag NPs in real time during thermal treatments by in situ optical microspectroscopy and complemented by transmission electron microscopy and X-ray diffraction characterization. The time variation in the surface plasmon resonance of Ag NPs is analyzed in the framework of Mie extinction theory in connection with nanocrystal precipitation in the supersaturated solid solutions. For the higher concentration of silver and tin, nucleation and growth processes were distinguished, which appeared to ... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4559229 Fri, 04 Mar 2011 10:49:37 +0100 4559229 http://www.medworm.com/index.php?rid=4559230&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fy3k3368712723427%2F Abstract  The physical mechanisms of metallic nanoparticles formation by laser technology were studied. The system air/Au film/glass was irradiated by laser at the conditions of surface plasmon resonance. A surface electromagnetic wave was excited in Kretchmann configuration by the fundamental and second harmonics of the Q-switched YAG/Nd+3 laser with pulse power density close to the threshold of melting. Nanostructuring of Au film was observed only for the second harmonic (λ = 0.532 μm) irradiation at the surface plasmon polariton resonance (SPR) conditions. Estimations were done using the interference model of the differently directed plasmon polariton waves excited by a surface electromagnetic wave on the metal surface. It was shown that a regular pattern of lo... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4559230 Thu, 03 Mar 2011 07:25:00 +0100 4559230 http://www.medworm.com/index.php?rid=4539959&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fx7147682u6655238%2F This study shows that the size of gold and silver nanoparticles can effect gold and silver nanoparticles’ absorption efficiency and scattering efficiency. The gold nanoparticle is found to possess the maximum absorption efficiency when the size of gold nanoparticle is 50 nm and the incident wavelength is 540 nm, and the increasing scattering efficiency with the increasing size of gold nanoparticle in the medium, and refractive index of the medium is around 1.33. However, the silver nanoparticle owns the maximum absorption efficiency when the size of silver nanoparticle is 20 nm and the incident wavelength is 396 nm, and the maximum scattering efficiency when the size of silver nanoparticle is 30 nm and the incident wavelength is 410 nm in the same medi... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4539959 Mon, 28 Feb 2011 16:45:56 +0100 4539959 http://www.medworm.com/index.php?rid=4539958&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F7434130818101532%2F Abstract  Conventionally, plasmonic lenses introduce a phase delay distribution across their surfaces by modulating the dimensions of nanostructures within a metal film. However, there is very limited modulation of the phase delay due to the small dependence of the mode propagation constant on the structure dimensions. In this paper, a novel design of plasmonic zone plate lenses (PZPL) with both slit width and refractive index modulation is proposed to enable integrating more slits in a fixed lens aperture with the extended phase delay range and, therefore, greatly enhance the performance of the devices. More than three-time enhancement of the light intensity at the focus is achieved compared to the structure with only slit width modulation. Like a conventional immersion sy... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4539958 Mon, 28 Feb 2011 16:45:56 +0100 4539958 http://www.medworm.com/index.php?rid=4539961&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F11m5827117471nw7%2F Abstract  The plasmonic spectra of solution phase ensembles of triangular silver nanoplates have been analysed in order to examine the fundamental properties underlying their size-dependent enhanced refractive index sensitivities. Linewidth studies highlight variations in the response of these solution phase nanostructures to those previously reported for single immobilized triangular nanostructures. The observation of insignificant broadening of the resonance linewidth for larger edge length nanoplates highlights minimal contribution of radiative damping processes at these dimensions. Comparative single nanoplate studies using discrete dipole approximations were performed to analyse the dephasing processes contributing to these reduced linewidths and to determine the key p... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4539961 Thu, 24 Feb 2011 17:19:42 +0100 4539961 http://www.medworm.com/index.php?rid=4539960&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Frv1u765110321453%2F Abstract  We consider a model utilizing the concept of impedance matching, which can be applied to design the coupled cascaded plasmonic cavity waveguide with desired properties. We use a transfer matrix method to obtain its transmission and dispersion diagrams. Base on this method, we demonstrate that a band-pass metal–dielectric–metal plasmonic filter with quasi-flat group velocity and tunable bandwidth can be achieved. Content Type Journal ArticlePages 1-7DOI 10.1007/s11468-011-9209-4Authors Yi Xu, Nonlinear Physics Centre and Centre for Ultra-high-bandwidth Devices for Optical Systems (CUDOS), Research School for Physics and Engineering, Australian National University, Mills Road (Bldg. 59), Canberra, ACT 0200, AustraliaAndrey E. Miroshnichenko, Nonlinear Physic... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4539960 Thu, 24 Feb 2011 17:19:42 +0100 4539960 http://www.medworm.com/index.php?rid=4539962&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fq7x1g81r2u151122%2F Abstract  Wavelength-dependent complex effective refractive index of dilute colloidal gold, i.e., spherical gold nanoparticles in water was measured using a reflectometer and a spectrophotometer. The spectral data obtained was used for the calculation of the wavelength-dependent complex permittivity of the gold nanoparticle with the aid of the Maxwell Garnett effective medium model for the colloid. It is shown that the wavelength-dependent complex permittivity of gold nanoparticle is different from the complex permittivity of bulk gold. Furthermore, Smakula’s formula is introduced for the calculation of the relative concentration of gold nanoparticles embedded in liquid using absorption data of the colloid. Content Type Journal ArticlePages 1-5DOI 10.1007/s11468-011-9... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4539962 Thu, 24 Feb 2011 17:19:41 +0100 4539962 http://www.medworm.com/index.php?rid=4511558&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fx4p1541417321084%2F Abstract  A three-dimensional silver metallic nanowires array which can realize negative refraction and image focusing in the visible frequency is presented. Homogeneous effective medium theory is used to investigate the negative refraction properties when the cell size of the array is much smaller than the incident wavelength. The analytical results are confirmed by Finite Difference Time Domain (FDTD) numerical simulations. The imaging properties comparison among the nanowires arrays with triangle, circle, ellipse, hexagon, and square wire cross-sections which have the same filling factor show the structure shapes of the nanowires will not influence the negative refraction but the imaging properties because of the different loss from the metal nanowires. Content Type ... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4511558 Mon, 21 Feb 2011 17:04:48 +0100 4511558 http://www.medworm.com/index.php?rid=4501042&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F83w36v6m8346586v%2F Abstract  We study the effect of a spiral corrugation on the outer surface of a fully metal-coated scanning near-field optical microscopy (SNOM) probe using the finite element method. The introduction of a novel form of asymmetry, devoid of any preferential spatial direction and covering the whole angular range of the originally axisymmetric tip, allows attaining strong field localization for a linearly polarised mode with arbitrary orientation. Compared to previously proposed asymmetric structures which require linearly polarised excitation properly oriented with respect to the asymmetry, such a configuration enables significant simplification in mode injection. In fact, not only is the need for the delicate procedure to generate radially polarised beams overcome, but also... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4501042 Thu, 17 Feb 2011 07:05:37 +0100 4501042 http://www.medworm.com/index.php?rid=4494338&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Ft83188227752k847%2F Abstract  We propose a plasmonic wavelength-launched Fresnel zone plate structure for subwavelength focusing. The plasmonic structure consists of a central circular groove surrounded by 12 transparent and opaque zones. All the zones with widths smaller than one half of the incident wavelength are used to enhance the field of evanescent waves in the transmission. Based on the finite-difference time-domain analysis, a focus spot with a full-width at half-maximum of 270 nm (= 0.4λ in ) can be achieved, accompanied by a largely reduced depolarization effect. The sharp waistline indicates that the surface waves are largely converged in the region of focus. Content Type Journal ArticlePages 1-4DOI 10.1007/s11468-010-9199-7Authors Jun Wang, School of Mechanical and Ae... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4494338 Wed, 16 Feb 2011 07:05:05 +0100 4494338 http://www.medworm.com/index.php?rid=4488671&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fp325782558803793%2F Abstract  Solution-processible fabrication techniques have been demonstrated with promising features for realizing different types of plasmonic devices, which combine interference lithography, spin-coating of the colloidal gold nanoparticles, and subsequent annealing process at a temperature of 200–300 °C. However, the resultant device needs to be improved in the following considerations: (1) The photoresist master grating needs to be removed for the applications in optoelectronic or sensor devices and (2) each lattice site of the photonic crystals is still composed of closely contacted gold nanoparticles. Actually, these metallic photonic structures can be refurbished through a further annealing process. Using an annealing temperature above 450 °C, we have su... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4488671 Fri, 11 Feb 2011 11:53:25 +0100 4488671 http://www.medworm.com/index.php?rid=4441648&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fa15p770675412667%2F Abstract  We derive closed analytical forms for the response of coaxial spoof plasmons, aided by transmission line concepts under the effective complex surface impedance framework. This constitutes a powerful platform to improve as well as to elucidate designs with enhanced performances. In particular, we propose a dual-band spoof plasmon waveguiding geometry with the higher order slow-wave mode operating well below the regime governed by dispersion of periodic guides (Bragg reflections at Brillouin zone boundaries), that is, diffraction. The analysis is supported by eigen mode numerical calculations. As an example in a waveguide device context, we demonstrate the dual-band planar routing ability of elliptical–coaxial cable-based spoof plasmons along a straight chain as w... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4441648 Thu, 03 Feb 2011 21:06:47 +0100 4441648 http://www.medworm.com/index.php?rid=4441649&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Frp76337325514171%2F Abstract  Has the 10-year-old quest for the optical superlens, based on Veselago’s hypothesis of negative refraction, been a chimaera? We argue that Pendry’s alternative prescription of the silver superlens is nothing more than an application of the natural phenomenon of surface plasmon resonance that occurs in the noble metal films. This phenomenon does not predict the reality of Veselago’s negative refractive index materials. We give a simple explanation of how this resonance achieves a field intensity enhancement at the interface of silver and air without involving the concept of negative refraction. Content Type Journal ArticlePages 1-3DOI 10.1007/s11468-011-9205-8Authors George Christou, School of Sciences, University of Nicosia, P.O. Box 24005, 1700 Nicosia... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4441649 Thu, 03 Feb 2011 07:07:33 +0100 4441649 http://www.medworm.com/index.php?rid=4418423&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F745n241176124868%2F Abstract  We discuss the interplay between surface plasmon polaritons (SPPs) and localized shape resonances (LSRs) in a plasmonic structure working as a photo-coupler for a GaAs quantum well photodetector. For a targeted electronic inter-subband transition inside the quantum well, maximum photon absorption is found by compromising two effects: the mode overlapping with incident light and the lifetime of the resonant photons. Under the optimal conditions, the LSR mediates the coupling between the incident light and plasmonic structure while the SPP provides long-lived resonance which is limited ultimately by metal loss. The present work provides insight to the design of plasmonic photo-couplers in semiconductor optoelectronic applications. Content Type Journal ArticlePag... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4418423 Thu, 27 Jan 2011 01:08:19 +0100 4418423 http://www.medworm.com/index.php?rid=4418424&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fn725gu045h2l2700%2F Abstract  The localized surface plasmon resonance (LSPR) spectrum of noble metal nanoparticles is studied by quasi-static approximation. Taking the sensitivity of LSPR shape to the size and shape of nanoparticle along with surrounding refractive index, parameters like refractive index sensitivity and sensing figure of merit have been determined. In the present analysis from the sensing relevant parameters, it is concluded that Ag represents a better sensing behavior than Au and Cu over the entire visible to infrared regime of EM spectrum. Content Type Journal ArticlePages 1-7DOI 10.1007/s11468-011-9206-7Authors Jagmeet Singh Sekhon, Department of Physics, Sant Longowal Institute of Engineering & Technology, Longowal, District-Sangrur, Punjab 148-106, IndiaS S Verma, De... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4418424 Thu, 27 Jan 2011 01:08:18 +0100 4418424 http://www.medworm.com/index.php?rid=4411019&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F54l33454kv964687%2F Abstract  A new quasi-3D structure composed of stacked double-layer subwavelength metal gratings is designed for magnetic resonance in the visible region. The coupling of two-layer gratings induces a type of magnetic plasmon propagation mode characterized by extraordinary optical transmission (EOT) with extremely high transmittance of up to 0.94 for transverse magnetic polarization. The results show that magnetic resonance is an effective method to enhance the transmittance and avoid much energy loss, one of the barriers for application in the visible region. The magnetic resonance or EOT is strongly dependent on the wavelength which can simply be tuned by the period of gratings. This work paves a way to designing metallic metamaterials that are magnetically active in the v... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4411019 Tue, 25 Jan 2011 23:35:49 +0100 4411019 http://www.medworm.com/index.php?rid=4411020&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fl77475481743301g%2F Abstract  In this paper, we show that surface plasmon polaritons (SPPs) can be sustained by a single row of holes periodically drilled on a perfect electric conductor surface. These SPPs can be strongly confined in the transverse plane and they possess an excellent modal shape. In the terahertz regime, large propagation length is available for highly confined SPPs on a real-metal surface waveguide. As the dispersion characteristics of such SPPs can be controlled by the surface geometry, unusual total reflection phenomenon occurs when waves travel along a nonuniform surface waveguide with gradually increasing hole depths. Content Type Journal ArticlePages 1-5DOI 10.1007/s11468-011-9204-9Authors Linfang Shen, Department of Information Science and Electronic Engineering, ... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4411020 Tue, 25 Jan 2011 23:35:47 +0100 4411020 http://www.medworm.com/index.php?rid=4376938&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fxj053337341273t0%2F Abstract  In this paper, we investigate the focusing properties of a plasmonic lens with multiple-turn spiral nano-structures, and analyze its field enhancement effect based on the phase matching theory and finite-difference time-domain simulation. The simulation result demonstrates that a left-hand spiral plasmonic lens can concentrate an incident right-hand circular polarization light into a focal spot with a high focal depth. The intensity of the focal spot could be controlled by altering the number of turns, the radius and the width of the spiral slot. And the focal spot is smaller and has a higher intensity compared to the incident linearly polarized light. This design can also eliminate the requirement of centering the incident beam to the plasmonic lens, making it po... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4376938 Mon, 17 Jan 2011 20:38:33 +0100 4376938 http://www.medworm.com/index.php?rid=4360094&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fn646611h057125k8%2F Abstract  We propose a subwavelength quarter-waveplate composed of four L-shaped nanoparticles that act as optical nanoantennas and investigate its optical properties using the finite-difference time-domain method. When polarization of the incident beam is parallel to one arm of the antenna, polarization of the scattering light rotates 45° with respect to that of the incident beam due to the symmetry of the L-shaped nanoantennas. Phase retardation is generated by changing the arm length of the antennas. The influence of the distance between the L-shaped nanoantennas on the far-field radiation is also discussed. Content Type Journal ArticlePages 1-4DOI 10.1007/s11468-010-9196-xAuthors Jing Yang, State Key Laboratory for Mesoscopic Physics and Department of Physics, Pek... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4360094 Sat, 15 Jan 2011 01:06:29 +0100 4360094 http://www.medworm.com/index.php?rid=4355286&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fgt178225k4062q20%2F Abstract  Gold–silver bimetallic film configuration is brought forward to realize surface plasmon resonance imaging (SPRI) biosensor with the virtues of both high sensitivity and chemical stability. The theoretical calculation is adopted to optimize the thicknesses of the metal films, and bimetallic film configuration with high refractive index sensitivity and a good linearity between reflectivity and refractive index is presented. Then, the property of the detection system is discussed. The results show that in comparison to most commercial SPRI biosensors which use single gold films, the sensitivity and molecule detection ability of the gold–silver bimetallic film configuration can be improved to a great extent. For the substrate of BAK3 glass used in this paper, the ... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4355286 Wed, 12 Jan 2011 17:09:01 +0100 4355286 http://www.medworm.com/index.php?rid=4355285&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fq503l1132nv323w7%2F We report in this paper the near-field distribution in the case of gold triangle arrays by means of two-photon polymerization for a dipole and a quadrupole plasmon mode. In order to link the finite difference in the time domain (FDTD) simulations of the triangle array and the experimental results, extinction spectra for both cases in air and SU-8 environments are shown. In case of the 40-nm thick gold triangles with 85-nm side-length, we show that the calculated and experimentally obtained near-field for the excited dipole mode has the same distribution along the polarization of the exciting laser beam. In case of bigger triangles of 540-nm side-length a quadrupole mode is excited, which leads to a rotation of the near-field distribution by 90° referred to the polarization of the be... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4355285 Wed, 12 Jan 2011 17:09:01 +0100 4355285 http://www.medworm.com/index.php?rid=4355287&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fywx08150x5k355rt%2F Abstract  In this article, we experimentally investigated the plasmonics interaction in the system composed of Ag nano-cubes on Ag film with controlled distance. The distance is controlled by Rhodamine B (RhB)-doped polymethylmethacrylate (PMMA) film as the spacer, whose fluorescence intensity was then enhanced by the plasmonics interaction. Experimental results show that the fluorescence enhancement is sensitive to the thickness of the spacer. The largest enhancement factor obtained is 521 with the RhB-doped PMMA film of 10 nm thickness. For comparison, we also presented the fluorescence enhancement caused by only the localized surface plasmons from Ag nano-cubes on glass substrate coated with RhB-doped PMMA film, which gives out lower enhancement factors at the same ... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4355287 Wed, 12 Jan 2011 17:09:00 +0100 4355287 http://www.medworm.com/index.php?rid=4326773&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fm032786515x57g52%2F Abstract  An elliptical nano-pinhole structure-based plasmonic lens was designed and investigated experimentally by means of focused ion beam nanofabrication, atomic force microscope imaging, and scanning near-field optical microscope (NSOM). Two scan modes, tip scan and sample scan, were employed, respectively, in our NSOM measurements. Both the scan modes have their characteristics while probing the plasmonic lenses. Our experimental results demonstrated that the lens can realize subwavelength focusing with elongated depth of focus. This type of lens can be used in micro-systems such as micro-opto-electrical–mechanical systems for biosensing, subwavelength imaging, and data storage. Content Type Journal ArticlePages 1-8DOI 10.1007/s11468-010-9191-2Authors Yiwei Zh... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4326773 Fri, 07 Jan 2011 14:51:32 +0100 4326773 http://www.medworm.com/index.php?rid=4326774&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fv6822133u3686l60%2F Abstract  In this work, the expanding thermal plasma chemical vapor deposition in combination with radio frequency magnetron sputtering is used to deposit dielectric/metal multi-layers with controlled size and density of nanoparticles. The multi-layer structure serves the purpose of increasing the nanoparticle number density, without changing the metal particle size, shape and the interparticle distance. The possibility of independently tuning and, therefore, controlling the nanoparticle size and number density allows developing surface plasmon resonance-based deep-colored coatings. The influence of the number of layers, metal surface area coverage, and thickness of the dielectric layer on the multi-layer nanostructure and on the developed color is presented here in detail.... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4326774 Fri, 07 Jan 2011 14:51:31 +0100 4326774 http://www.medworm.com/index.php?rid=4326775&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fy723738q01887681%2F Abstract  In recent years, metal hollow nanostructures are intriguing to be synthesized and studied because they exhibit unique surface plasmonic properties. Although many methods for tuning the surface plasmonic absorption peaks of silver nanostructures have been reported, it still remains a great challenge to produce hollow Ag nanostructure with controllable surface plasmon resonance (SPR) via a facile method. In this paper, triangular Au–Ag nanoframes were successfully fabricated using triangular silver nanoplates as templates, through galvanic replacement reaction between the silver nanoplates and HAuCl4, exhibiting tuneable SPR response from visible (605 nm) to near-infrared region (1,235 nm). Content Type Journal ArticlePages 1-4DOI 10.1007/s11468-010-9... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4326775 Thu, 06 Jan 2011 17:56:53 +0100 4326775 http://www.medworm.com/index.php?rid=4321985&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fl2n63376767274k4%2F Abstract  Surface plasmon resonance (SPR) absorption spectra of gold nanodisks hexagonally arranged in planar arrays have been studied by using coupled dipole method and quasi-static approximation. The calculation results reveal that the increasing aspect ratio (AR) of gold disks in the close-packed nanoarray leads to SPR blue shift firstly and then red shift. The critical AR corresponding to the maximum blue shift can be controlled by tuning the interparticle distance and particle size. The physical mechanism of this non-monotonic SPR shift is investigated based on the competition between the influences from shape factor and arranging structure of the array. Although increasing the semi-minor axis of gold disk reduces the AR and leads to a blue shift of SPR, this increasin... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4321985 Wed, 05 Jan 2011 16:52:29 +0100 4321985 http://www.medworm.com/index.php?rid=4321984&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fv1gq15343l4j56k5%2F Abstract  Three types of indirect phase tuning-based plasmonic structures with subwavelength circular grooves/slits and/or central apertures corrugated on Au film supported by glass substrate: depth modulation, width modulation, and hybrid depth-width modulation, were put forth in this paper. They were investigated experimentally by means of nanofabrication and near-filed scanning optical microscope characterization. The plasmonic structures were fabricated using the technique of focused ion beam direct milling. Our experimental results demonstrated that all of the phase tuning-based structures have focusing functions. Both the width and depth modulation-based structures can realize beam focusing and produce an elongated depth of focus. Moreover, after comparison among thes... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4321984 Wed, 05 Jan 2011 16:52:29 +0100 4321984 http://www.medworm.com/index.php?rid=4244566&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F753554v7740130j6%2F Abstract  Surface plasma oscillations in metallic particles as well as in thin metallic films have been studied extensively in the past decades. New features regarding surface plasma excitations are, however, constantly discovered, leading, for example, to surface-enhanced Raman scattering studies and enhanced optical transmission though metal films with nanohole arrays. In the present work, the role of a metallic substrate is examined in two cases, one involving an overcoat of dielectric nanoparticles and the other an overcoat of metallic nanoparticles. Theoretical results are obtained by modeling the nanoparticles as forming a two-dimensional, hexagonal lattice of spheres. The scattered electromagnetic field is then calculated using a variant of the Green function method.... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4244566 Tue, 07 Dec 2010 13:48:26 +0100 4244566 http://www.medworm.com/index.php?rid=4241019&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fl6957551n517x40m%2F Abstract  The dependence of nanoparticle size on surface-enhanced Raman scattering (SERS) from silver film over nanospheres substrate is studied. For a range of nanosphere sizes from 430 to 1,500 nm, optimum SERS signal is obtained with a nanosphere size of 1,000 nm at an excitation wavelength of 532 nm. We have clarified the physical origin of this optimization in an unambiguious way as due to resonant plasmonic excitations from 3D finite-difference time-domain simulations, as well as with the assistance of UV-visible reflectance spectrum. Content Type Journal ArticleDOI 10.1007/s11468-010-9188-xAuthors Wen-Chi Lin, Institute of Optoelectronic Sciences, National Taiwan Ocean University, No. 2 Pei-Ning Rd., 202 Keelung, Taiwan Republic of ChinaLu-Shing L... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4241019 Mon, 06 Dec 2010 18:49:32 +0100 4241019 http://www.medworm.com/index.php?rid=4166899&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fj28401180h406834%2F We report the use of biocompatible gold nanorods (GNRs) as multimodal (plasmonic and magnetic) probes for cancer cell labeling in vitro. These multifunctional and multimodal bioconjugates were prepared by replacing cetyltrimethylammonium bromide with a mixture of functionalized PEGylation molecules so that a variety of functionalities (e.g., magnetic resonance imaging agent gadolinium (Gd) and biorecognition molecule transferrin (Tf)) can be easily integrated using simple chemistry. It was shown that Gd incorporation did not interfere with the plasmonic properties of the GNRs and a strong T1 relaxivity was estimated (10.0 mM−1 s−1), which is more than twice that of the clinical MRI agent Gd-DTPA. The large observed T1 relaxivity was possibly due to the huge surface to volu... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4166899 Thu, 11 Nov 2010 06:58:02 +0100 4166899 http://www.medworm.com/index.php?rid=4158234&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F52624741t1836247%2F Abstract  The transverse mode electron oscillations contribute to most of the surface-enhanced Raman scattering (SERS) intensity from the nanorod array substrates. To enhance the transverse mode electron oscillation and improve the SERS enhancements, the local electric field distribution of the orthogonal-nanorod structures, composed of two parallel horizontal nanorods in between two parallel vertical nanorods, has been studied. The local electric fields of the longitudinal mode along the horizontal nanorods act as the excitation for the transverse mode electron oscillations in vertical nanorods, leading to the cascade enhancements of the electric fields around the vertical nanorods. In addition, the plasmon peaks of the longitudinal modes can be tuned by changing the lengt... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4158234 Tue, 09 Nov 2010 12:52:51 +0100 4158234 http://www.medworm.com/index.php?rid=4142393&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F37n7274704808611%2F Abstract  Metal-capped microdisk cavity supporting surface plasmon polaritons (SPP)-guided whispering gallery mode (WGM) can achieve higher cavity factor Q than traditional microdisk cavity in sub-wavelength dimensions. We have numerically analyzed the limiting factors on Q using finite difference time domain method. The Q of SPP-guided WGM is primarily limited by the loss of metal. A thin metal-sandwiched microdisk cavity supporting long-range surface plasmon polariton mode was proposed to reduce the metal loss. The proposed cavities have been shown to increase cavity Q by more than 15-fold and reduce threshold gain by more than threefold as opposed to traditional microdisk cavities. Content Type Journal ArticleDOI 10.1007/s11468-010-9185-0Authors Yi-Hao Chen, EECS Dep... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4142393 Fri, 05 Nov 2010 11:05:12 +0100 4142393 http://www.medworm.com/index.php?rid=4142394&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fl077718204t1q0vg%2F We report experimentally the remote excitation surface plasmon and consequent enhancement of surface-enhanced Raman scattering (SERS) using evanescent wave propagating in quasi-one-dimensional (Q1D) MoO3 ribbon dielectric waveguide. The propagating dielectric waveguide along Q1D MoO3 ribbon is realized experimentally, when the 632.8 nm laser radiates on the one side edge of Q1D MoO3 ribbon. The remote excitation SERS spectra-enhanced by chemical and electromagnetic field mechanisms are measured, respectively, where silver (Ag) nanoparticles are excited by electromagnetic field after propagating 7.3 μm in the ribbon. The chemical mechanism for the remote excitation SERS is contributed from the charge transfer between the analyte molecule and MoO3 ribbon. The electromagnetic fi... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4142394 Tue, 02 Nov 2010 17:33:55 +0100 4142394 http://www.medworm.com/index.php?rid=4116858&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fn88x71426673703u%2F Abstract  Localized surface plasmon resonance (LSPR) for longitudinal mode of gold nanorod is simulated by using Gans theory. The parameters like surface scattering, radiation damping, and dynamic depolarization of radiation across the surface of nanorod affecting response of free electrons towards optical excitation are considered. Simulation results show that refractive index sensitivity linearly rises with size and aspect ratio, whereas this leads to the broadening of resonant line width also. Therefore, to optimize the size of nanorod, figure of merit (FOM) is calculated and observed that optimized width is 15 nm for an aspect ratio of 2, whereas it is 12 nm for aspect ratios 3 and 4. Further, optimization by using newly modified figure of merit (MFOM) shows t... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4116858 Wed, 27 Oct 2010 16:16:44 +0100 4116858 http://www.medworm.com/index.php?rid=4095782&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2F0640334609m66310%2F Abstract  Gold nanohole arrays are fabricated with focused ion beam irradiating gold thin film supported on quartz substrate. The topography of the nanohole arrays is characterized using an atomic force microscope, and the near-field optical transmission properties of the nanohole array are investigated with a near-field scanning optical microscope. Our experimental results verify the near-optical transmission performance and further demonstrate that they are in agreement with the theoretical calculation results. The enhanced optical transmission of the nanohole arrays are expected to be used for a variety of applications in sensor and photonics devices. Content Type Journal ArticleDOI 10.1007/s11468-010-9183-2Authors Rongjing He, School of Physical Electronics, Unive... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4095782 Fri, 22 Oct 2010 18:29:47 +0100 4095782 http://www.medworm.com/index.php?rid=4095783&cid=s_33310_61_f&fid=33310&url=http%3A%2F%2Fwww.springerlink.com%2Fcontent%2Fy878175504n4k2xh%2F Abstract  This paper explores geometry-sensitive scattering from plasmonic nanoparticles deposited on top of a thin-film amorphous silicon solar cell to enhance light trapping in the photo-active layer. Considering the nanoparticles as ideal spheroids, the broadband optical absorption by the silicon layer is analyzed and optimized with respect to the nanoparticle aspect ratio in both the cases of resonant (silver) and nonresonant (aluminum) plasmonic nanostructures. It is demonstrated how the coupling of sunlight with the semiconductor can be improved through tuning the nanoparticle shape in both the dipolar and multi-polar scattering regimes, as well as discussed how the native oxide shell formed on the nanospheroid surface after the prolonged action of air and moisture af... Plasmonics journals http://www.medworm.com/rss/comments.php?id=4095783 Fri, 22 Oct 2010 18:29:46 +0100 4095783