WorldWideScience

Sample records for plasmon resonance properties

  1. Noble metal nanostructures for double plasmon resonance with tunable properties

    Science.gov (United States)

    Petr, M.; Kylián, O.; Kuzminova, A.; Kratochvíl, J.; Khalakhan, I.; Hanuš, J.; Biederman, H.

    2017-02-01

    We report and compare two vacuum-based strategies to produce Ag/Au materials characterized by double plasmon resonance peaks: magnetron sputtering and method based on the use of gas aggregation sources (GAS) of nanoparticles. It was observed that the double plasmon resonance peaks may be achieved by both of these methods and that the intensities of individual localized surface plasmon resonance peaks may be tuned by deposition conditions. However, in the case of sputter deposition it was necessary to introduce a separation dielectric interlayer in between individual Ag and Au nanoparticle films which was not the case of films prepared by GAS systems. The differences in the optical properties of sputter deposited bimetallic Ag/Au films and coatings consisted of individual Ag and Au nanoparticles produced by GAS is ascribed to the divers mechanisms of nanoparticles formation.

  2. Metal nanoparticles with sharp corners: Universal properties of plasmon resonances

    CERN Document Server

    Sturman, B; Gorkunov, M

    2012-01-01

    We predict the simultaneous occurrence of two fundamental phenomena for metal nanoparticles possessing sharp corners: First, the main plasmonic dipolar mode experiences strong red shift with decreasing corner curvature radius; its resonant frequency is controlled by the apex angle of the corner and the normalized (to the particle size) corner curvature. Second, the split-off plasmonic mode experiences strong localization at the corners. Altogether, this paves the way for tailoring of metal nano-structures providing wavelength-selective excitation of localized plasmons and a strong near-field enhancement of linear and nonlinear optical phenomena.

  3. Metal nanoparticles with sharp corners: Universal properties of plasmon resonances

    Science.gov (United States)

    Sturman, B.; Podivilov, E.; Gorkunov, M.

    2013-03-01

    We predict the simultaneous occurrence of two fundamental phenomena for metal nanoparticles possessing sharp corners with variable curvature: First, the main dipolar plasmonic mode experiences a strong red shift with increasing corner curvature; for large values of the curvature, the resonant frequency is controlled by the apex angle of the corner. Second, the split-off plasmonic mode experiences a strong localization at the corners. Altogether, this paves the way for the tailoring of metal nanostructures providing a wavelength-selective excitation of localized plasmons and a strong near-field enhancement of linear and nonlinear optical phenomena.

  4. Optical properties of surface plasmon resonances of coupled metallic nanorods.

    Science.gov (United States)

    Smythe, Elizabeth J; Cubukcu, Ertugrul; Capasso, Federico

    2007-06-11

    We present a systematic study of optical antenna arrays, in which the effects of coupling between the antennas, as well as of the antenna length, on the reflection spectra are investigated and compared. Such arrays can be fabricated on the facet of a fiber, and we propose a photonic device, a plasmonic optical antenna fiber probe, that can potentially be used for in-situ chemical and biological detection and surface-enhanced Raman scattering.

  5. Resonance hybridization and near field properties of strongly coupled plasmonic ring dimer-rod nanosystem

    Energy Technology Data Exchange (ETDEWEB)

    Koya, Alemayehu Nana; Ji, Boyu; Hao, Zuoqiang; Lin, Jingquan, E-mail: linjingquan@cust.edu.cn [School of Science, Changchun University of Science and Technology, Changchun 130022 (China)

    2015-09-21

    Combined effects of polarization, split gap, and rod width on the resonance hybridization and near field properties of strongly coupled gold dimer-rod nanosystem are comparatively investigated in the light of the constituent nanostructures. By aligning polarization of the incident light parallel to the long axis of the nanorod, introducing small split gaps to the dimer walls, and varying width of the nanorod, we have simultaneously achieved resonance mode coupling, huge near field enhancement, and prolonged plasmon lifetime. As a result of strong coupling between the nanostructures and due to an intense confinement of near fields at the split and dimer-rod gaps, the extinction spectrum of the coupled nanosystem shows an increase in intensity and blueshift in wavelength. Consequently, the near field lifespan of the split-nanosystem is prolonged in contrast to the constituent nanostructures and unsplit-nanosystem. On the other hand, for polarization of the light perpendicular to the long axis of the nanorod, the effect of split gap on the optical responses of the coupled nanosystem is found to be insignificant compared to the parallel polarization. These findings and such geometries suggest that coupling an array of metallic split-ring dimer with long nanorod can resolve the huge radiative loss problem of plasmonic waveguide. In addition, the Fano-like resonances and immense near field enhancements at the split and dimer-rod gaps imply the potentials of the nanosystem for practical applications in localized surface plasmon resonance spectroscopy and sensing.

  6. The influence of edge and corner evolution on plasmon properties and resonant edge effect in gold nanoplatelets.

    Science.gov (United States)

    Xu, Xi-Bin; Luo, Jiang-Shan; Liu, Miao; Wang, Yu-Ying; Yi, Zao; Li, Xi-Bo; Yi, You-Gen; Tang, Yong-Jian

    2015-01-28

    In this paper a simulation of the properties of surface plasmons on gold nanoplatelets with various cross-sections inscribed in a circle and an investigation of their field distributions to assign multiple SPRs are described. The manipulated propagation can be obtained through the evolution of edges and corners. Furthermore, the particle morphology and the associated spectral positions alone do not uniquely reflect the important details of the local field distribution or the resonance modes. The plasmon modes were investigated and found to be mainly excited along the edges and in the side and sloped side surfaces. The strong field distributions can generally be found around the corners and how the plasmons transmit through the corners to adjacent edges was also investigated. Besides the plasmons excited along the edges as were found for the triangular nanoplatelets, plasmons were excited in the interior region of the triangular surfaces and were also investigated. Despite this in the infrared region, plasmon modes were found to be along the edges for the hexagonal nanoplatelets. Also, it can be seen that the change of nanoplatelet thickness can support different plasmon modes ranging from dipolar resonance mode to quadrupole resonance mode. The thickness far below the skin depth can display complex plasmon modes along the edges and on the side and sloping side surfaces as well as the strong coupling between the top and bottom surfaces. The observed plasmon resonance modes in this simulation reflect the interference of all these contributions including the plasmons along the edges and on the side surfaces. This is an essential step towards a thorough understanding of plasmon modes and the effect of edge and corner evolution in polygonous nanoplatelets.

  7. Plasmon resonance enhancement of nonlinear properties of amino acids

    Science.gov (United States)

    de Araujo, Renato E.; Rativa, Diego; Gomes, Anderson S. L.

    2007-02-01

    Here we analyze the influence of 9 nm (mean diameter) silver particles on the nonlinear properties of intrinsic cell molecules. A novel high sensitivity thermal managed eclipse Z-scan technique with a femtosecond laser system was used to analyze the nonlinear susceptibility of water solution of fluorescent and non-fluorescent amino acids (Tryptophan, Tyrosine, Phenylalanine, Proline and Histidine) with different concentration of silver nanoparticles. The generalized Maxwell Garnett model is used to explain the behavior of the measured nonlinear refractive index with the change of the nanoparticles concentration in the sample.

  8. Self-assembly of large-scale and ultrathin silver nanoplate films with tunable plasmon resonance properties.

    Science.gov (United States)

    Zhang, Xiao-Yang; Hu, Anming; Zhang, Tong; Lei, Wei; Xue, Xiao-Jun; Zhou, Yunhong; Duley, Walt W

    2011-11-22

    We describe a rapid, simple, room-temperature technique for the production of large-scale metallic thin films with tunable plasmonic properties assembled from size-selected silver nanoplates (SNPs). We outline the properties of a series of ultrathin monolayer metallic films (8-20 nm) self-assembled on glass substrates in which the localized surface plasmon resonance can be tuned over a range from 500 to 800 nm. It is found that the resonance peaks of the films are strongly dependent on the size of the nanoplates and the refractive index of the surrounding dielectric. It is also shown that the bandwidth and the resonance peak of the plasmon resonance spectrum of the metallic films can be engineered by simply controlling aggregation of the SNP. A three-dimensional finite element method was used to investigate the plasmon resonance properties for individual SNPs in different dielectrics and plasmon coupling in SNP aggregates. A 5-17 times enhancement of scattering from these SNP films has been observed experimentally. Our experimental results, together with numerical simulations, indicate that this self-assembly method shows great promise in the production of nanoscale metallic films with enormous electric-field enhancements at visible and near-infrared wavelengths. These may be utilized in biochemical sensing, solar photovoltaic, and optical processing applications.

  9. Tuned longitudinal surface plasmon resonance and third-order nonlinear optical properties of gold nanorods.

    Science.gov (United States)

    Tsutsui, Yushi; Hayakawa, Tomokatsu; Kawamura, Go; Nogami, Masayuki

    2011-07-08

    In order to elucidate the relationship for third-order nonlinear optical properties of anisotropic metal nanoparticles between the incident laser wavelength and surface plasmon resonance (SPR) wavelength, gold nanorods (GNRs) with a tuned longitudinal SPR mode in frequency were prepared by seed-mediated methods with two different surfactants, cetyltrimethylammonium bromide (CTAB) and benzyldimethylammonium chloride (BDAC). The real and imaginary parts of the third-order nonlinear optical susceptibilities χ(3) were examined by near-infrared (800 nm) femtosecond Z-scan and I-scan techniques for various gold sols with SPR wavelengths of 530 nm (spheres), 800 nm (nanorods) and 1000 nm (nanorods), named as 530GNSs, 800GNRs and 1000GNRs, respectively. All the samples showed intrinsically third-order nonlinear optical refractive responses. However, as for the real part of χ(3) for one particle, 800GNRs whose plasmon peak was tuned to the incident laser wavelength exhibited a Reχ(3) value 45 times stronger than 530GNSs. More interestingly, the imaginary part of χ(3) was more greatly influenced at the tuned SPR wavelength. Here we first demonstrate that 800GNRs showed plasmon-enhanced saturable absorption (SA) due to a longitudinal SPR tuned to the incident laser wavelength.

  10. Scattering properties of vein induced localized surface plasmon resonances on a gold disk

    KAUST Repository

    Amin, Muhammad

    2011-12-01

    It is demonstrated via simulations that a gold nano-disk with a non-concentric cavity supports localized surface plasmon resonances over a frequency band that includes the visible and the near-infrared parts of the spectrum. The charge distribution on the disk indicates that the two distinct peaks in the scattering cross section are due to the (hybridized) higher-order plasmon modes; plasmon hybridization that involves the dipole modes of the disk and the cavity enforces the "coupling" of the plane-wave excitation to the originally-dark higher-order modes. It is further demonstrated that the resonance frequencies can be tuned by varying the radius of the embedded non-concentric cavity. The near-field enhancement observed at these two tunable resonance frequencies suggests that the proposed structure can be used as a substrate in surface enhanced spectroscopy applications. © 2011 IEEE.

  11. Optical properties of local surface plasmon resonance in Ag/ITO sliced nanosphere by the discrete dipole approximation

    Energy Technology Data Exchange (ETDEWEB)

    Haiwei, Mu; Jingwei, Lv; Zhaoting, Liu; Lin, Yang; Qiang, Liu; Chao, Liu [Northeast Petroleum University, School of Electronics Science, Daqing (China); Shijie, Zheng [Harbin Institute of Technology, School of Civil Engineering, Harbin (China); Tao, Sun [Agency for Science, Technology and Research (A-STAR), Institute of Microelectronics, Singapore (Singapore)

    2016-04-15

    Optical properties of localized surface plasmon resonances (LSPR) of Ag/ITO sliced nanosphere have been studied using discrete dipole approximation and plasmon hybridization theory. It is found that different morphologies of sliced nanosphere can induce distinctive features in the extinction spectra. In the meanwhile, gap distances and refractive index of the surrounding medium could modulate the plasmon hybridization and the LSPR shifting. At large separation, the shift of LSPR peaks for the nanosphere sliced in halves consisting of ITO and Ag is small and insensitive to the gap distance in the weak coupling, whereas smaller separation exhibits a distinct red shift. Additionally, multiple resonance peaks are excited for the nanosphere sliced in quarters consisting of ITO and Ag. In this situation, electric field is mainly distributed in the gap region of sliced nanosphere and the central point. These results indicate that different morphologies of sliced nanosphere could create abundant tunable LSPR modes, which provides potential for multiplex optical sensing. (orig.)

  12. Surface characterization and antifouling properties of nanostructured gold chips for imaging surface plasmon resonance biosensing

    NARCIS (Netherlands)

    Joshi, S.; Pellacani, P.; Beek, van T.A.; Zuilhof, H.; Nielen, M.W.F.

    2015-01-01

    Surface Plasmon Resonance (SPR) optical sensing is a label-free technique for real-time monitoring of biomolecular interactions. Recently, a portable imaging SPR (iSPR) prototype instrument, featuring a nanostructured gold chip, has been developed. In the present work, we investigated the crucial

  13. Use of surface plasmon resonance to investigate lateral wall deposition kinetics and properties of polydopamine films.

    Science.gov (United States)

    Li, Hui; Cui, Dafu; Cai, Haoyuan; Zhang, Lulu; Chen, Xing; Sun, Jianhai; Chao, Yapeng

    2013-03-15

    Dopamine (DA) is a particularly important neurotransmitter. Polydopamine (pDA) films have been demonstrated to be important materials for the immobilization of biomolecules onto almost any type of solid substrate. In this study, a surface plasmon resonance (SPR)-based sensor system with the sensor chip surface parallel to the direction of gravity was used to investigate the lateral wall deposition kinetics and properties of pDA films. The deposition kinetics of pDA Films are limited by the oxidation process. The pDA film could not be removed from the sensor chip completely by a strongly alkaline solution, indicating that the pDA film was heterogeneous in the direction of deposition. The pDA film formed near the interior of the solution was less stable than the film formed near the gold-solution interface. Adsorption of proteins on pDA film was studied compared with that on bare gold and dextran sensor chip. The reduction of Au(111) cations by the pDA film, forming a layer of gold particles, was monitored using SPR.

  14. Large-scale synthesis and surface plasmon resonance properties of angled silver/silver homojunction nanowires

    Science.gov (United States)

    Lai, Xuandi; Feng, Xiumei; Zhang, Menghuan; Hong, Ruijin; Chen, Yongxiang; Li, Aiqing; Deng, Xiulong; Hu, Jianqiang

    2014-03-01

    Angled silver/silver (Ag/Ag) homojunction nanowires (HNWs) with an average diameter of about 72 nm have been prepared by a straightforward and effective solvothermal method. The synthesis involves a one-step, non-seed, and template-less process to large-scale Ag/Ag HNWs, which is low-cost and proceeds at moderate temperatures. Two neighboring Ag nanorods or nanowires were connected into obtuse angle by Ag/Ag homojunction. It was found that synthesizing Ag/Ag HNWs were very sensitive to reaction temperature and polyvinylpyrrolidone concentration. Only through finely controlling these reaction parameters, the high-quality Ag/Ag HNWs could be formed in large scale and their surface plasmon resonance properties could be effectively tailored. High-resolution transmission electron microscopy and selected area electron diffraction investigations showed that the Ag/Ag HNWs were generated with a twinned crystalline structure. We also proposed a primary experimental model to illustrate the growth mechanism of the angled Ag/Ag HNWs.

  15. Combined surface acoustic wave and surface plasmon resonance measurement of collagen and fibrinogen layer physical properties

    Directory of Open Access Journals (Sweden)

    J.-M. Friedt

    2016-12-01

    Full Text Available We use an instrument combining optical (surface plasmon resonance and acoustic (Love mode surface acoustic wave device real-time measurements on a same surface for the identification of water content in collagen and fibrinogen protein layers. After calibration of the surface acoustic wave device sensitivity by copper electrodeposition and surfactant adsorption, the bound mass and its physical properties – density and optical index – are extracted from the complementary measurement techniques and lead to thickness and water ratio values compatible with the observed signal shifts. Such results are especially usefully for protein layers with a high water content as shown here for collagen on an hydrophobic surface. We obtain the following results: collagen layers include 70±20% water and are 16±3 to 19±3 nm thick for bulk concentrations ranging from 30 to 300 μg/ml. Fibrinogen layers include 50±10% water for layer thicknesses in the 6±1.5 to 13±2 nm range when the bulk concentration is in the 46 to 460 μg/ml range.

  16. Triple plasmon resonance of bimetal nanoshell

    Energy Technology Data Exchange (ETDEWEB)

    Shirzaditabar, Farzad [Department of Physics, Razi University, Kermanshah (Iran, Islamic Republic of); Saliminasab, Maryam, E-mail: m.saliminasab@yahoo.com [Young Researchers Club, Kermanshah Branch, Islamic Azad University, Kermanshah (Iran, Islamic Republic of); Arghavani Nia, Borhan [Department of Physics, Kermanshah Branch, Islamic Azad University, Kermanshah (Iran, Islamic Republic of)

    2014-07-15

    In this paper, light absorption spectra properties of a bimetal multilayer nanoshell based on quasi-static approach are investigated. Comparing with silver-dielectric-silver and silver-dielectric-gold nanoshells, gold-dielectric-silver nanoshells have three intense and separated plasmon peaks which are more suitable for multiplex biosensing. Calculations show that relatively small thickness of outer silver shell and large dielectric constant of middle dielectric layer of gold-dielectric-silver nanoshell are suitable to obtain the triple plasmon resonance.

  17. Triple plasmon resonance of bimetal nanoshell

    Science.gov (United States)

    Shirzaditabar, Farzad; Saliminasab, Maryam; Arghavani Nia, Borhan

    2014-07-01

    In this paper, light absorption spectra properties of a bimetal multilayer nanoshell based on quasi-static approach are investigated. Comparing with silver-dielectric-silver and silver-dielectric-gold nanoshells, gold-dielectric-silver nanoshells have three intense and separated plasmon peaks which are more suitable for multiplex biosensing. Calculations show that relatively small thickness of outer silver shell and large dielectric constant of middle dielectric layer of gold-dielectric-silver nanoshell are suitable to obtain the triple plasmon resonance.

  18. Localized surface plasmon resonance induced structure-property relationships of metal nanostructures

    Science.gov (United States)

    Vilayurganapathy, Subramanian

    The confluence of nanotechnology and plasmonics has led to new and interesting phenomena. The industrial need for fast, efficient and miniature devices which constantly push the boundaries on device performance tap into the happy marriage between these diverse fields. Designing devices for real life application that give superior performance when compared with existing ones are enabled by a better understanding of their structure-property relationships. Among all the design constraints, without doubt, the shape and size of the nanostructure along with the dielectric medium surrounding it has the maximum influence on the response and thereby the performance of the device. Hence a careful study of the above mentioned parameters is of utmost importance in designing efficient devices. In this dissertation, we synthesize and study the optical properties of nanostructures of different shapes and size. In particular, we estimated the plasmonic near field enhancement via surface-enhanced Raman scattering (SERS) and 2-photon Photoemission electron microscopy (2P-PEEM). We synthesized the nanostructures using four different techniques. One synthesis technique, the thermal growth method was employed to grow interesting Ag and Au nanostructures on Si. The absence of toxic chemicals during nanostructure synthesis via the thermal growth technique opens up myriad possibilities for applications in the fields of biomedical science, bioengineering, drug delivery among others along with the huge advantage of being environment friendly. The other three synthesis techniques (ion implantation, Electrodeposition and FIB lithography) were chosen with the specific goal of designing novel plasmonic metal, metal hybrid nanostructures as photocathode materials in next generation light sources. The synthesis techniques for these novel nanostructures were dictated by the requirement of high quantum efficiency, robustness under constant irradiation and coherent unidirectional electron emission

  19. Plasmon resonances in nanoparticles, their applications to magnetics and relation to the Riemann hypothesis

    Science.gov (United States)

    Mayergoyz, I. D.

    2012-05-01

    The review of the mathematical treatment of plasmon resonances as an eigenvalue problem for specific boundary integral equations is presented and general properties of plasmon spectrum are outlined. Promising applications of plasmon resonances to magnetics are described. Interesting relation of eigenvalue treatment of plasmon resonances to the Riemann hypothesis is discussed.

  20. Electrically Tunable Plasmonic Resonances with Graphene

    DEFF Research Database (Denmark)

    Emani, Naresh K.; Chung, Ting-Fung; Ni, Xingjie

    2012-01-01

    Real time switching of a plasmonic resonance may find numerous applications in subwavelength optoelectronics, spectroscopy and sensing. We take advantage of electrically tunable interband transitions in graphene to control the strength of the plasmonic resonance.......Real time switching of a plasmonic resonance may find numerous applications in subwavelength optoelectronics, spectroscopy and sensing. We take advantage of electrically tunable interband transitions in graphene to control the strength of the plasmonic resonance....

  1. Surface plasmon resonance in super-periodic metal nanostructures

    Science.gov (United States)

    Leong, Haisheng

    Surface plasmon resonances in periodic metal nanostructures have been investigated over the past decade. The periodic metal nanostructures have served as new technology platforms in fields such as biological and chemical sensing. An existing method to determine the surface plasmon resonance properties of these metal nanostructures is the measurement of the light transmission or reflection from these nanostructures. The measurement of surface plasmon resonances in either the transmission or reflection allows one to resolve the surface plasmon resonance in metal nanostructures. In this dissertation, surface plasmon resonances in a new type of metal nanostructures were investigated. The new nanostructures were created by patterning traditional periodic nanohole and nanoslit arrays into diffraction gratings. The patterned nanohole and 11anoslit arrays have two periods in the structures. The new nanostructures are called "super-periodic" nanostructures. With rigorous finite difference time domain (FDTD) numerical simulations, surface plasmon resonances in super-periodic nanoslit and nanohole arrays were investigated. It was found that by creating a super-period in periodic metal nanostructures, surface plasmon radiations can be observed in the non-zero order diffractions. This discovery presents a new method of characterizing the surface plasmon resonances in metal nanostructures. Super-periodic gold nanoslit and nanohole arrays were fabricated with the electron beam lithography technique. The surface plasmon resonances were measured in the first order diffraction by using a CCD. The experimental results confirm well with the FDTD numerical simulations.

  2. Integrated plasmonic refractometric sensor using Fano resonance

    Science.gov (United States)

    Sherif, S. M.; Zografopoulos, D. C.; Shahada, L. A.; Beccherelli, R.; Swillam, M.

    2017-02-01

    We propose a plasmonic refractometric sensor that is based on Fano resonances excited in a resonant rectangular cavity coupled to a metal-insulator-metal bus waveguide. The properties of the resonances are controlled by varying the dimensions of the rectangular resonator and the observed Fano profile stems from the multimode interference of resonant cavity modes. We theoretically investigate the device’s performance as a highly sensitive refractometric plasmonic sensor which operates on gases, water and organic solvent solutions with tens of femtoliters of analyte. The sensor is studied in a wide operational range (0.7-2.7 μm) covering the entire near infrared spectral range, and is characterized by large sensitivity, which reaches 1550 nm RIU-1, and sensitivity per unit volume higher than 107 nm (RIU · nl)-1 at the resonant wavelength of 1.55 μm. The proposed plasmonic structure is very promising for integrated sensing applications owing to its small footprint and surprisingly simple layout.

  3. Enhancement of surface plasmon resonances on the nonlinear optical properties in a GaAs quantum dot

    Science.gov (United States)

    Jiang, Xiancong; Guo, Kangxian; Liu, Guanghui; Yang, Tao; Yang, Yanlian

    2017-05-01

    In this paper, the nonlinear optical properties of a metallic nanoparticle (MNP)-semiconductor quantum dot (SQD) hybrid nanosystem with the hybrid exciton effect have been studied. Considering the influence of quantum-size effect to the dielectric function of MNP, the quantum corrected dielectric function was applied to our calculation. By using the compact-density-matrix method, the interaction between MNP and SQD has been studied theoretically. The results show that the surface plasmon resonances (SPRs) of MNP enhance indeed the nonlinear optical properties of SQD. Further more, the enhancement depends on two factors: (a) the center-to-center 7distance between MNP and SQD; (b) the radius ratio between MNP and SQD.

  4. Nonlinear plasmonic resonances in graphene nanostructures

    Science.gov (United States)

    You, Jian Wei; Weismann, Martin; Panoiu, Nicolae C.

    2016-09-01

    Peculiar physical properties of graphene offer remarkable potential for advanced photonics, particularly in the area of nonlinear optics at deep-subwavelength scale. In this article, we use a theoretical and computational analysis to demonstrate an efficient mechanism for enhancing the third-harmonic generation in graphene diffraction gratings. By taking advantage of the relation between the resonance wavelength of localized surface-plasmon polaritons of graphene ribbons and disks their specific geometry, we can engineer the spectral response of graphene gratings so as strong plasmonic resonances exist at both the fundamental frequency and third-harmonic (TH). As a result of this dual resonance mechanism for optical near-field enhancement, the intensity of the TH can be increased greatly.

  5. Gold nanodisk array surface plasmon resonance sensor

    Science.gov (United States)

    Tian, Xueli

    Surface plasmon resonances in periodic metal nanostructures have been investigated for sensing applications over the last decade. The resonance wavelengths of the nanostructures are usually measured in the transmission or reflection spectrum for chemical and biological sensing. In this thesis, I introduce a nanoscale gap mediated surface plasmon resonance nanodisk array for displacement sensing and a super-period gold nanodisk grating enabled surface plasmon resonance spectrometer sensor. The super-period gold nanodisk grating has a small subwavelength period and a large diffraction grating period. Surface plasmon resonance spectra are measured in the first order diffraction spatial profiles captured by a charge-coupled device (CCD). A surface plasmon resonance sensor for the bovine serum albumin (BSA) protein nanolayer bonding is demonstrated by measuring the surface plasmon resonance shift in the first order diffraction spatial intensity profiles captured by the CCD.

  6. Spatial Coherence Properties of Organic Molecules Coupled to Plasmonic Surface Lattice Resonances in the Weak and Strong Coupling Regimes

    CERN Document Server

    Shi, L; Rekola, H T; Martikainen, J -P; Moerland, R J; Törmä, P

    2014-01-01

    We study spatial coherence properties of a system composed of periodic silver nanoparticle arrays covered with a fluorescent organic molecule (DiD) film. The evolution of spatial coherence of this composite structure from the weak to the strong coupling regime is investigated by systematically varying the coupling strength between the localized DiD excitons and the collective, delocalized modes of the nanoparticle array known as surface lattice resonances. A gradual evolution of coherence from the weak to the strong coupling regime is observed, with the strong coupling features clearly visible in interference fringes. A high degree of spatial coherence is demonstrated in the strong coupling regime, even when the mode is very excitonlike (80%), in contrast to the purely localized nature of molecular excitons. We show that coherence appears in proportion to the weight of the plasmonic component of the mode throughout the weak-to-strong coupling crossover, providing evidence for the hybrid nature of the normal m...

  7. Plasmonic propagations distances for interferometric surface plasmon resonance biosensing

    OpenAIRE

    Lepage Dominic; Carrier Dominic; Jiménez Alvaro; Beauvais Jacques; Dubowski Jan

    2011-01-01

    Abstract A surface plasmon resonance (SPR) scheme is proposed in which the local phase modulations of the coupled plasmons can interfere and yield phase-sensitive intensity modulations in the measured signal. The result is an increased traceability of the SPR shifts for biosensing applications. The main system limitation is the propagation distance of the coupled plasmon modes. This aspect is therefore studied for thin film microstructures operating in the visible and near-infrared spectral r...

  8. Nonlinear plasmonic amplification via dissipative soliton-plasmon resonances

    Science.gov (United States)

    Ferrando, Albert

    2017-01-01

    In this contribution we introduce a strategy for the compensation of plasmonic losses based on a recently proposed nonlinear mechanism: the resonant interaction between surface plasmon polaritons and spatial solitons propagating in parallel along a metal/dielectric/Kerr structure. This mechanism naturally leads to the generation of a quasiparticle excitation, the so-called soliplasmon resonance. We analyze the role played by the effective nonlinear coupling inherent to this system and how this can be used to provide a mechanism of quasiresonant nonlinear excitation of surface plasmon polaritons. We will pay particular attention to the introduction of asymmetric linear gain in the Kerr medium. The unique combination of nonlinear propagation, nonlinear coupling, and gain give rise to a scenario for the excitation of long-range surface plasmon polaritons with distinguishing characteristics. The connection between plasmonic losses and soliplasmon resonances in the presence of gain will be discussed.

  9. Spatial filtering with surface plasmon resonance systems

    Science.gov (United States)

    Ghosh, A. K.; Siddharth, V.; Bhagat, M.; Aggarwal, S.; Anurag, P.; Jain, M.

    2007-09-01

    Surface plasmon resonance based sensors are most useful in measuring the refractive indices of biochemicals. In such sensors a beam of light obliquely incident at an interface of glass and metallic thin film excites resonant plasmon waves in the metal if the angle of incidence or the wavelength is selected properly. The resonance conditions are changed by the refractive indices of any material in contact with the metal film. When resonance occurs the light beam is absorbed strongly. We can easily show that the phenomenon of surface plasmon resonance in such a system acts as a high quality spatial notch or band rejection filter.

  10. Electrical Modulation of Fano Resonance in Plasmonic Nanostructures Using Graphene

    DEFF Research Database (Denmark)

    Emani, Naresh K.; Chung, Ting-Fung; Kildishev, Alexander V.;

    2014-01-01

    Pauli blocking of interband transistions gives rise to tunable optical properties in single layer graphene (SLG). This effect is exploited in a graphene-nanoantenna hybrid device where Fano resonant plasmonic nanostructures are fabricated on top of a graphene sheet. The use of Fano resonant......-element simulations. Our approach can be used for development of next generation of tunable plasmonic and hybrid nanophotonic devices....

  11. Laser printing of resonant plasmonic nanovoids

    Science.gov (United States)

    Kuchmizhak, A.; Vitrik, O.; Kulchin, Yu.; Storozhenko, D.; Mayor, A.; Mirochnik, A.; Makarov, S.; Milichko, V.; Kudryashov, S.; Zhakhovsky, V.; Inogamov, N.

    2016-06-01

    found to be laser energy-tunable. Resonant light scattering from individual nanovoids was observed in the visible spectral range, using dark-field confocal microspectroscopy, with the size-dependent resonant peak positions. These colored geometric resonances in far-field scattering were related to excitation and interference of transverse surface plasmon modes in nanovoid shells. Plasmon-mediated electromagnetic field enhancement near the nanovoids was evaluated via finite-difference time-domain calculations for their model shapes simulated by three-dimensional molecular dynamics, and experimentally verified by means of photoluminescence microscopy and Raman spectroscopy. Electronic supplementary information (ESI) available: Sections: (1) Eu3+(TTA) synthesis and optical properties; (2) SERS enhancement factor calculations; (3) features of the Ag nanovoid formation; (4) nanovoid printing on the Si substrate; (5) dark-field microspectroscopy details; (6) effective refractive index estimations; (7) calculated E-field distributions near the parabolic-shaped nanovoids; (8) plasmonic PL enhancement for the parabolic- and conical-shaped nanovoids. Fig. S1-S7. See DOI: 10.1039/c6nr01317a

  12. Coupling Bright and Dark Plasmonic Lattice Resonances

    CERN Document Server

    Rodriguez, S R K; Maes, B; Janssen, O T A; Vecchi, G; Rivas, J Gomez

    2011-01-01

    We demonstrate the coupling of bright and dark Surface Lattice Resonances (SLRs), which are collective Fano resonances in 2D plasmonic crystals. As a result of this coupling, a frequency stop-gap in the dispersion relation of SLRs is observed. The different field symmetries of the low and high frequency SLR bands lead to pronounced differences in their coupling to free space radiation. Standing waves of very narrow spectral width compared to localized surface plasmon resonances are formed at the high frequency band edge, while subradiant damping onsets at the low frequency band edge leading the resonance into darkness. We introduce a coupled oscillator analog to the plasmonic crystal, which serves to elucidate the physics of the coupled plasmonic resonances and to estimate very high quality factors (Q>700) for SLRs, which are the highest known for any 2D plasmonic crystal.

  13. Plasmonic propagations distances for interferometric surface plasmon resonance biosensing

    Directory of Open Access Journals (Sweden)

    Lepage Dominic

    2011-01-01

    Full Text Available Abstract A surface plasmon resonance (SPR scheme is proposed in which the local phase modulations of the coupled plasmons can interfere and yield phase-sensitive intensity modulations in the measured signal. The result is an increased traceability of the SPR shifts for biosensing applications. The main system limitation is the propagation distance of the coupled plasmon modes. This aspect is therefore studied for thin film microstructures operating in the visible and near-infrared spectral regions. The surface roughness of the substrate layer is examined for different dielectrics and deposition methods. The Au layer, on which the plasmonic modes are propagating and the biosensing occurs, is also examined. The surface roughness and dielectric values for various deposition rates of very thin Au films are measured. We also investigate an interferometric SPR setup where, due to the power flux transfer between plasmon modes, the specific choice of grating coupler can either decrease or increase the plasmon propagation length.

  14. Plasmonic propagations distances for interferometric surface plasmon resonance biosensing.

    Science.gov (United States)

    Lepage, Dominic; Carrier, Dominic; Jiménez, Alvaro; Beauvais, Jacques; Dubowski, Jan J

    2011-05-17

    A surface plasmon resonance (SPR) scheme is proposed in which the local phase modulations of the coupled plasmons can interfere and yield phase-sensitive intensity modulations in the measured signal. The result is an increased traceability of the SPR shifts for biosensing applications. The main system limitation is the propagation distance of the coupled plasmon modes. This aspect is therefore studied for thin film microstructures operating in the visible and near-infrared spectral regions. The surface roughness of the substrate layer is examined for different dielectrics and deposition methods. The Au layer, on which the plasmonic modes are propagating and the biosensing occurs, is also examined. The surface roughness and dielectric values for various deposition rates of very thin Au films are measured. We also investigate an interferometric SPR setup where, due to the power flux transfer between plasmon modes, the specific choice of grating coupler can either decrease or increase the plasmon propagation length.

  15. Tunable Omnidirectional Surface Plasmon Resonance in Cylindrical Plasmonic Structure

    Institute of Scientific and Technical Information of China (English)

    WANG Yi; WANG Bing; ZHOU Zhi-Ping

    2008-01-01

    @@ The tunable omnidirectional surface plasmon resonance in the optical range is theoretically demonstrated in a cylindrical plasmonic crystal by using rigorous coupled-wave analysis.The cylindrical plasmonic crystal consists of an infinite chain of two-dimensional cylindrical metal-dielectric-dielectric-metal structures.The dispersion relation of the cylindrical plasmonic crystal is obtained by calculating the absorptance as a function of a TM-polarized incident plane wave and its in-plane wave vector.The omnidirectional surface plasmon resonance can be tuned from UV region to visible region by adjusting the thickness of the cylindrical dielectric layers.The absorption spectrum of the infinite chain of nanocylinders is also investigated for comparison.

  16. Plasmonic Gold Decorated MWCNT Nanocomposite for Localized Plasmon Resonance Sensing

    Science.gov (United States)

    Ozhikandathil, J.; Badilescu, S.; Packirisamy, M.

    2015-01-01

    The synergism of excellent properties of carbon nanotubes and gold nanoparticles is used in this work for bio-sensing of recombinant bovine growth hormones (rbST) by making Multi Wall Carbon Nanotubes (MWCNT) locally optically responsive by augmenting it optical properties through Localized Surface Plasmon Resonance (LSPR). To this purpose, locally gold nano particles decorated gold–MWCNT composite was synthesized from a suspension of MWCNT bundles and hydrogen chloroauric acid in an aqueous solution, activated ultrasonically and, then, drop-casted on a glass substrate. The slow drying of the drop produces a “coffee ring” pattern that is found to contain gold–MWCNT nanocomposites, accumulated mostly along the perimeter of the ring. The reaction is studied also at low-temperature, in the vacuum chamber of the Scanning Electron Microscope and is accounted for by the local melting processes that facilitate the contact between the bundle of tubes and the gold ions. Biosensing applications of the gold–MWCNT nanocomposite using their LSPR properties are demonstrated for the plasmonic detection of traces of bovine growth hormone. The sensitivity of the hybrid platform which is found to be 1 ng/ml is much better than that measuring with gold nanoparticles alone which is only 25 ng/ml. PMID:26282187

  17. Plasmonic Gold Decorated MWCNT Nanocomposite for Localized Plasmon Resonance Sensing

    Science.gov (United States)

    Ozhikandathil, J.; Badilescu, S.; Packirisamy, M.

    2015-08-01

    The synergism of excellent properties of carbon nanotubes and gold nanoparticles is used in this work for bio-sensing of recombinant bovine growth hormones (rbST) by making Multi Wall Carbon Nanotubes (MWCNT) locally optically responsive by augmenting it optical properties through Localized Surface Plasmon Resonance (LSPR). To this purpose, locally gold nano particles decorated gold-MWCNT composite was synthesized from a suspension of MWCNT bundles and hydrogen chloroauric acid in an aqueous solution, activated ultrasonically and, then, drop-casted on a glass substrate. The slow drying of the drop produces a “coffee ring” pattern that is found to contain gold-MWCNT nanocomposites, accumulated mostly along the perimeter of the ring. The reaction is studied also at low-temperature, in the vacuum chamber of the Scanning Electron Microscope and is accounted for by the local melting processes that facilitate the contact between the bundle of tubes and the gold ions. Biosensing applications of the gold-MWCNT nanocomposite using their LSPR properties are demonstrated for the plasmonic detection of traces of bovine growth hormone. The sensitivity of the hybrid platform which is found to be 1 ng/ml is much better than that measuring with gold nanoparticles alone which is only 25 ng/ml.

  18. Electron energy-loss spectroscopy of branched gap plasmon resonators

    Science.gov (United States)

    Raza, Søren; Esfandyarpour, Majid; Koh, Ai Leen; Mortensen, N. Asger; Brongersma, Mark L.; Bozhevolnyi, Sergey I.

    2016-12-01

    The miniaturization of integrated optical circuits below the diffraction limit for high-speed manipulation of information is one of the cornerstones in plasmonics research. By coupling to surface plasmons supported on nanostructured metallic surfaces, light can be confined to the nanoscale, enabling the potential interface to electronic circuits. In particular, gap surface plasmons propagating in an air gap sandwiched between metal layers have shown extraordinary mode confinement with significant propagation length. In this work, we unveil the optical properties of gap surface plasmons in silver nanoslot structures with widths of only 25 nm. We fabricate linear, branched and cross-shaped nanoslot waveguide components, which all support resonances due to interference of counter-propagating gap plasmons. By exploiting the superior spatial resolution of a scanning transmission electron microscope combined with electron energy-loss spectroscopy, we experimentally show the propagation, bending and splitting of slot gap plasmons.

  19. Effect of Ag nanostructures and annealing process on the localized surface plasmon resonance properties of Ag-based AZO films

    Science.gov (United States)

    Jin, Jing; Hui, Chaoxian; Liu, Can; Shi, Weimin

    2017-08-01

    Ag nanoparticles were obtained in Ag/AZO and AZO/Ag/AZO films by magnetron sputtering method at room temperature with different deposition time. The morphology of Ag nanoparticles is strongly affected by the particle size, shape and distribution as well as annealing temperatures, which determine the optical response of films. The high quality of AZO film with better crystallinity can enhance the optical transmittance and a good coverage by AZO as top layer on Ag nanoparticles can also enhance the surface plasmon resonance (SPR) absorption of Ag in long wavelengths. The mechanisms involved in shifts and broadening of SPR peaks have been explained detailedly. The effect of annealing process on SPR of Ag and photoelectric properties of AZO/Ag/AZO films can be also discussed. It is shown that the SPR peak of 664 nm only appears in AZO/Ag (5 s)/AZO film and no SPR peaks are found in annealed AZO/Ag/AZO films. The AZO/Ag (20 s)/AZO film annealed at 300 °C shows a great figure of merit (F_{{TC}}) of 4.8 × 10-2 Ω-1 because of high visible optical average transmittance of 85% and low sheet resistance (R_{{S}}) of 4.1 Ω/sq. The overall results reveal that annealing process can improve the electrical property of film and may not be able to promote the SPR of Ag nanoparticles, especially when AZO top layer is added. The introduction of Ag nanoparticles in AZO/Ag/AZO films should be very effective for improving the SPR or photoelectric properties of films depending on deposition conditions and annealing process.

  20. Collective resonances in plasmonic crystals: Size matters

    CERN Document Server

    Rodriguez, S R K; Berrier, A; Rivas, J Gomez

    2013-01-01

    Periodic arrays of metallic nanoparticles may sustain Surface Lattice Resonances (SLRs), which are collective resonances associated with the diffractive coupling of Localized Surface Plasmon Resonances (LSPRs). By investigating a series of arrays with varying number of particles, we traced the evolution of SLRs to its origins. Polarization resolved extinction spectra of arrays formed by a few nanoparticles were measured, and found to be in very good agreement with calculations based on a coupled dipole model. Finite size effects on the optical properties of the arrays are observed, and our results provide insight into the characteristic length scales for collective plasmonic effects: for arrays smaller than 5 x 5 particles, the Q-factors of SLRs are lower than those of LSPRs; for arrays larger than 20 x 20 particles, the Q-factors of SLRs saturate at a much larger value than those of LSPRs; in between, the Q-factors of SLRs are an increasing function of the number of particles in the array.

  1. Distributed optical fiber surface plasmon resonance sensors

    Institute of Scientific and Technical Information of China (English)

    Zhenxin Cao; Lenan Wu; Dayong Li

    2006-01-01

    @@ The relationships of the resonant wavelength of optical fiber surface plasmon resonance (SPR) sensors to the modulation layer refractive index, thickness and the refractive index of the bulk medium are obtained by using theoretical calculation model of optical fiber SPR sensors under certain conditions, which indicates that resonant wavelength of the sensors is approximately linear with modulation layer thickness. Based on the linear relationship, multiple SPR sensors with different resonant wavelengths can be fabricated in a single optical fiber named as distributed optical fiber surface plasmon resonance sensors (DOFSPRSs).Experimental results are presented, showing that it is practical to fabricate more than one SPR sensors in a single optical fiber.

  2. Active Molecular Plasmonics: Controlling Plasmon Resonances with Molecular Switches

    KAUST Repository

    Zheng, Yue Bing

    2009-02-11

    A gold nanodisk array, coated with bistable, redox-controllable [2]rotaxane molecules, when exposed to chemical oxidants and reductants, undergoes switching of its plasmonic properties reversibly. By contrast, (i) bare gold nanodisks and (ii) disks coated with a redox-active, but mechanically inert, control compound do not display surface-plasmon-based switching. Along with calculations based on time-dependent density functional theory, these experimental observations suggest that the nanoscale movements within surface-bound “molecular machines” can be used as the active components in plasmonic devices.

  3. Critical coupling in plasmonic resonator arrays

    Science.gov (United States)

    Balci, Sinan; Kocabas, Coskun; Aydinli, Atilla

    2011-08-01

    We report critical coupling of electromagnetic waves to plasmonic cavity arrays fabricated on Moiré surfaces. Dark field plasmon microscopy imaging and polarization dependent spectroscopic reflection measurements reveal the critical coupling conditions of the cavities. The critical coupling conditions depend on the superperiod of the Moiré surface, which also defines the coupling between the cavities. Complete transfer of the incident power can be achieved for traveling wave plasmonic resonators, which have a relatively short superperiod. When the superperiod of the resonators increases, the coupled resonators become isolated standing wave resonators in which complete transfer of the incident power is not possible. Analytical and finite difference time domain calculations support the experimental observations.

  4. Engineering optical properties using plasmonic nanostructures

    Science.gov (United States)

    Tamma, Venkata Ananth

    Plasmonic nanostructures can be engineered to take on unusual optical properties not found in natural materials. The optical responses of plasmonic materials are functions of the structural parameters and symmetry of the nanostructures, material parameters of the nanostructure and its surroundings and the incidence angle, frequency and polarization state of light. The scattering and hence the visibility of an object could be reduced by coating it with a plasmonic material. In this thesis, presented is an optical frequency scattering cancelation device composed of a silicon nanorod coated by a plasmonic gold nanostructure. The principle of operation was theoretically analyzed using Mie theory and the device design was verified by extensive numerical simulations. The device was fabricated using a combination of nanofabrication techniques such as electron beam lithography and focused ion beam milling. The optical responses of the scattering cancelation device and a control sample of bare silicon rod were directly visualized using near-field microscopy coupled with heterodyne interferometric detection. The experimental results were analyzed and found to match very well with theoretical prediction from numerical simulations thereby validating the design principles and our implementation. Plasmonic nanostructures could be engineered to exhibit unique optical properties such as Fano resonance characterized by narrow asymmetrical lineshape. We present dynamic tuning and symmetry lowering of Fano resonances in plasmonic nanostructures fabricated on flexible substrates. The tuning of Fano resonance was achieved by application of uniaxial mechanical stress. The design of the nanostructures was facilitated by extensive numerical simulations and the symmetry lowering was analyzed using group theoretical methods. The nanostructures were fabricated using electron beam lithography and optically characterized for various mechanical stress. The experimental results were in good

  5. Nanometrology using localized surface plasmon resonance spectroscopy

    DEFF Research Database (Denmark)

    Jeppesen, Claus; Lindstedt, Daniel N.; Laurberg, Asger V.;

    2013-01-01

    A novel optical characterization technique called localized surface plasmon resonance (LSPR) spectroscopy is presented. LSPR spectroscopy exploits light excited surface plasmons, which are collective coherent electron oscillations at a metal/dielectric interface. The LSPR can be observed in a tra......A novel optical characterization technique called localized surface plasmon resonance (LSPR) spectroscopy is presented. LSPR spectroscopy exploits light excited surface plasmons, which are collective coherent electron oscillations at a metal/dielectric interface. The LSPR can be observed...... in a transmission spectrum and it is very sensitive to the constituent materials as well as both lateral and vertical dimensions of the structures. This makes LSPR spectroscopy interesting for a number of applications including nanometrology. Like scatterometry, LSPR spectroscopy requires test structures...

  6. Quantum optical properties in plasmonic systems

    Science.gov (United States)

    Ooi, C. H. Raymond

    2015-04-01

    Plasmonic metallic particle (MP) can affect the optical properties of a quantum system (QS) in a remarkable way. We develop a general quantum nonlinear formalism with exact vectorial description for the scattered photons by the QS. The formalism enables us to study the variations of the dielectric function and photon spectrum of the QS with the particle distance between QS and MP, exciting laser direction, polarization and phase in the presence of surface plasmon resonance (SPR) in the MP. The quantum formalism also serves as a powerful tool for studying the effects of these parameters on the nonclassical properties of the scattered photons. The plasmonic effect of nanoparticles has promising possibilities as it provides a new way for manipulating quantum optical properties of light in nanophotonic systems.

  7. Non-blinking quantum dot with a plasmonic nanoshell resonator

    Science.gov (United States)

    Ji, Botao; Giovanelli, Emerson; Habert, Benjamin; Spinicelli, Piernicola; Nasilowski, Michel; Xu, Xiangzhen; Lequeux, Nicolas; Hugonin, Jean-Paul; Marquier, Francois; Greffet, Jean-Jacques; Dubertret, Benoit

    2015-02-01

    Colloidal semiconductor quantum dots are fluorescent nanocrystals exhibiting exceptional optical properties, but their emission intensity strongly depends on their charging state and local environment. This leads to blinking at the single-particle level or even complete fluorescence quenching, and limits the applications of quantum dots as fluorescent particles. Here, we show that a single quantum dot encapsulated in a silica shell coated with a continuous gold nanoshell provides a system with a stable and Poissonian emission at room temperature that is preserved regardless of drastic changes in the local environment. This novel hybrid quantum dot/silica/gold structure behaves as a plasmonic resonator with a strong Purcell factor, in very good agreement with simulations. The gold nanoshell also acts as a shield that protects the quantum dot fluorescence and enhances its resistance to high-power photoexcitation or high-energy electron beams. This plasmonic fluorescent resonator opens the way to a new family of plasmonic nanoemitters with robust optical properties.

  8. Dark Field Imaging of Plasmonic Resonator Arrays

    Science.gov (United States)

    Aydinli, Atilla; Balci, Sinan; Karademir, Ertugrul; Kocabas, Coskun

    2012-02-01

    We present critical coupling of electromagnetic waves to plasmonic cavity arrays fabricated on Moir'e surfaces. The critical coupling condition depends on the superperiod of Moir'e surface, which also defines the coupling between the cavities. Complete transfer of the incident power can be achieved for traveling wave plasmonic resonators, which have relatively short superperiod. When the superperiod of the resonators increases, the coupled resonators become isolated standing wave resonators in which complete transfer of the incident power is not possible. Dark field plasmon microscopy imaging and polarization dependent spectroscopic reflection measurements reveal the critical coupling conditions of the cavities. We image the light scattered from SPPs in the plasmonic cavities excited by a tunable light source. Tuning the excitation wavelength, we measure the localization and dispersion of the plasmonic cavity mode. Dark field imaging has been achieved in the Kretschmann configuration using a supercontinuum white light laser equipped with an acoustooptic tunable filter. Polarization dependent spectroscopic reflection and dark field imaging measurements are correlated and found to be in agreement with FDTD simulations.

  9. Surface Plasmon Resonance Evaluation of Colloidal Metal Aerogel Filters

    Science.gov (United States)

    Smith, David D.; Sibille, Laurent; Cronise, Raymond J.; Noever, David A.

    1997-01-01

    Surface plasmon resonance imaging has in the past been applied to the characterization of thin films. In this study we apply the surface plasmon technique not to determine macroscopic spatial variations but rather to determine average microscopic information. Specifically, we deduce the dielectric properties of the surrounding gel matrix and information concerning the dynamics of the gelation process from the visible absorption characteristics of colloidal metal nanoparticles contained in aerogel pores. We have fabricated aerogels containing gold and silver nanoparticles. Because the dielectric constant of the metal particles is linked to that of the host matrix at the surface plasmon resonance, any change 'in the dielectric constant of the material surrounding the metal nanoparticles results in a shift in the surface plasmon wavelength. During gelation the surface plasmon resonance shifts to the red as the average or effective dielectric constant of the matrix increases. Conversely, formation of an aerogel or xerogel through supercritical extraction or evaporation of the solvent produces a blue shift in the resonance indicating a decrease in the dielectric constant of the matrix. From the magnitude of this shift we deduce the average fraction of air and of silica in contact with the metal particles. The surface area of metal available for catalytic gas reaction may thus be determined.

  10. Molecular active plasmonics: controlling plasmon resonances with molecular machines

    KAUST Repository

    Zheng, Yue Bing

    2009-08-26

    The paper studies the molecular-level active control of localized surface plasmon resonances (LSPRs) of Au nanodisk arrays with molecular machines. Two types of molecular machines - azobenzene and rotaxane - have been demonstrated to enable the reversible tuning of the LSPRs via the controlled mechanical movements. Azobenzene molecules have the property of trans-cis photoisomerization and enable the photo-induced nematic (N)-isotropic (I) phase transition of the liquid crystals (LCs) that contain the molecules as dopant. The phase transition of the azobenzene-doped LCs causes the refractive-index difference of the LCs, resulting in the reversible peak shift of the LSPRs of the embedded Au nanodisks due to the sensitivity of the LSPRs to the disks\\' surroundings\\' refractive index. Au nanodisk array, coated with rotaxanes, switches its LSPRs reversibly when it is exposed to chemical oxidants and reductants alternatively. The correlation between the peak shift of the LSPRs and the chemically driven mechanical movement of rotaxanes is supported by control experiments and a time-dependent density functional theory (TDDFT)-based, microscopic model.

  11. Fano resonance Rabi splitting of surface plasmons.

    Science.gov (United States)

    Liu, Zhiguang; Li, Jiafang; Liu, Zhe; Li, Wuxia; Li, Junjie; Gu, Changzhi; Li, Zhi-Yuan

    2017-08-14

    Rabi splitting and Fano resonance are well-known physical phenomena in conventional quantum systems as atoms and quantum dots, arising from strong interaction between two quantum states. In recent years similar features have been observed in various nanophotonic and nanoplasmonic systems. Yet, realization of strong interaction between two or more Fano resonance states has not been accomplished either in quantum or in optical systems. Here we report the observation of Rabi splitting of two strongly coupled surface plasmon Fano resonance states in a three-dimensional plasmonic nanostructure consisting of vertical asymmetric split-ring resonators. The plasmonic system stably supports triple Fano resonance states and double Rabi splittings can occur between lower and upper pairs of the Fano resonance states. The experimental discovery agrees excellently with rigorous numerical simulations, and is well explained by an analytical three-oscillator model. The discovery of Fano resonance Rabi splitting could provide a stimulating insight to explore new fundamental physics in analogous atomic systems and could be used to significantly enhance light-matter interaction for optical sensing and detecting applications.

  12. Plasmon resonance in multilayer graphene nanoribbons

    DEFF Research Database (Denmark)

    Emani, Naresh Kumar; Wang, Di; Chung, Ting Fung

    2015-01-01

    Plasmon resonances in nanopatterned single-layer graphene nanoribbons (SL-GNRs), double-layer graphene nanoribbons (DL-GNRs) and triple-layer graphene nanoribbons (TL-GNRs) are studied experimentally using 'realistic' graphene samples. The existence of electrically tunable plasmons in stacked...... multilayer graphene nanoribbons was first experimentally verified by infrared microscopy. We find that the strength of the plasmonic resonance increases in DL-GNRs when compared to SL-GNRs. However, further increase was not observed in TL-GNRs when compared to DL-GNRs. We carried out systematic full......-wave simulations using a finite-element technique to validate and fit experimental results, and extract the carrier-scattering rate as a fitting parameter. The numerical simulations show remarkable agreement with experiments for an unpatterned SLG sheet, and a qualitative agreement for a patterned graphene sheet...

  13. Plasmon Resonance in Multilayer Graphene Nanoribbons

    CERN Document Server

    Emani, Naresh Kumar; Chung, Ting-Fung; Prokopeva, Ludmila J; Kildishev, Alexander V; Shalaev, Vladimir M; Chen, Yong P; Boltasseva, Alexandra

    2015-01-01

    Plasmon resonance in nanopatterned single layer graphene nanoribbon (SL-GNR), double layer graphene nanoribbon (DL-GNR) and triple layer graphene nanoribbon (TL-GNR) structures is studied both experimentally and by numerical simulations. We use 'realistic' graphene samples in our experiments to identify the key bottle necks in both experiments and theoretical models. The existence of electrical tunable plasmons in such stacked multilayer GNRs was first experimentally verified by infrared microscopy. We find that the strength of the plasmonic resonance increases in DL-GNR when compared to SL-GNRs. However, we do not find a further such increase in TL-GNRs compared to DL-GNRs. We carried out systematic full wave simulations using finite element technique to validate and fit experimental results, and extract the carrier scattering rate as a fitting parameter. The numerical simulations show remarkable agreement with experiments for unpatterned SLG sheet, and a qualitative agreement for patterned graphene sheet. W...

  14. Surface Plasmon Resonance Studies on Molecular Imprinting

    Directory of Open Access Journals (Sweden)

    Baoping Lin

    2002-01-01

    Full Text Available The molecular imprinted polymer (MIP members were fabricated with the print molecule L-phenylalanine ethyl ester. The elution and adsorption procedures were investigated by surface plasmon resonance in situ. The changes of refractive angle during elution procedure suggest that the MIP is prepared on the base of the non-covalent interactions. This MIP member sensor can achieve enantioselective recognition.

  15. Nanostructured imaging surface plasmon resonance biosensing

    NARCIS (Netherlands)

    Joshi, Sweccha

    2017-01-01

    The testing and further development of a prototype nanostructured imaging surface plasmon resonance (iSPR) biosensor, with a focus on surface modification and detailed characterization of the biosensor chip and in-field and at-line applicability in the food industry is described. Furthermore, a simp

  16. Nanostructured imaging surface plasmon resonance biosensing

    NARCIS (Netherlands)

    Joshi, Sweccha

    2017-01-01

    The testing and further development of a prototype nanostructured imaging surface plasmon resonance (iSPR) biosensor, with a focus on surface modification and detailed characterization of the biosensor chip and in-field and at-line applicability in the food industry is described. Furthermore, a

  17. Spoof surface plasmon Fabry-Perot open resonators in a surface-wave photonic crystal

    CERN Document Server

    Gao, Zhen; Xu, Hongyi; Zhang, Youming; Zhang, Baile

    2016-01-01

    We report on the proposal and experimental realization of a spoof surface plasmon Fabry-Perot (FP) open resonator in a surface-wave photonic crystal. This surface-wave FP open resonator is formed by introducing a finite line defect in a surface-wave photonic crystal. The resonance frequencies of the surface-wave FP open resonator lie exactly within the forbidden band gap of the surface-wave photonic crystal and the FP open resonator uses this complete forbidden band gap to concentrate surface waves within a subwavelength cavity. Due to the complete forbidden band gap of the surface-wave photonic crystal, a new FP plasmonic resonance mode that exhibits monopolar features which is missing in traditional FP resonators and plasmonic resonators is demonstrated. Near-field response spectra and mode profiles are presented in the microwave regime to characterize properties of the proposed FP open resonator for spoof surface plasmons.

  18. Hybrid plasmonic-photonic resonators (Conference Presentation)

    Science.gov (United States)

    Koenderink, A. Femius; Doeleman, Hugo M.; Ruesink, Freek; Verhagen, Ewold; Osorio, Clara I.

    2016-09-01

    Hybrid nanophotonic structures are structures that integrate different nanoscale platforms to harness light-matter interaction. We propose that combinations of plasmonic antennas inside modest-Q dielectric cavities can lead to very high Purcell factors, yielding plasmonic mode volumes at essentially cavity quality factors. The underlying physics is subtle: for instance, how plasmon antennas with large cross sections spoil or improve cavities and vice versa, contains physics beyond perturbation theory, depending on interplays of back-action, and interferences. This is evident from the fact that the local density of states of hybrid systems shows the rich physics of Fano interferences. I will discuss recent scattering experiments performed on toroidal microcavities coupled to plasmon particle arrays that probe both cavity resonance shifts and particle polarizability changes illustrating these insights. Furthermore I will present our efforts to probe single plasmon antennas coupled to emitters and complex environments using scatterometry. An integral part of this approach is the recently developed measurement method of `k-space polarimetry', a microscopy technique to completely classify the intensity and polarization state of light radiated by a single nano-object into any emission direction that is based on back focal plane imaging and Stokes polarimetry. I show benchmarks of this technique for the cases of scattering, fluorescence, and cathodoluminescence applied to directional surface plasmon polariton antennas.

  19. Hollow metal nanostructures for enhanced plasmonics: synthesis, local plasmonic properties and applications

    Science.gov (United States)

    Genç, Aziz; Patarroyo, Javier; Sancho-Parramon, Jordi; Bastús, Neus G.; Puntes, Victor; Arbiol, Jordi

    2017-01-01

    Metallic nanostructures have received great attention due to their ability to generate surface plasmon resonances, which are collective oscillations of conduction electrons of a material excited by an electromagnetic wave. Plasmonic metal nanostructures are able to localize and manipulate the light at the nanoscale and, therefore, are attractive building blocks for various emerging applications. In particular, hollow nanostructures are promising plasmonic materials as cavities are known to have better plasmonic properties than their solid counterparts thanks to the plasmon hybridization mechanism. The hybridization of the plasmons results in the enhancement of the plasmon fields along with more homogeneous distribution as well as the reduction of localized surface plasmon resonance (LSPR) quenching due to absorption. In this review, we summarize the efforts on the synthesis of hollow metal nanostructures with an emphasis on the galvanic replacement reaction. In the second part of this review, we discuss the advancements on the characterization of plasmonic properties of hollow nanostructures, covering the single nanoparticle experiments, nanoscale characterization via electron energy-loss spectroscopy and modeling and simulation studies. Examples of the applications, i.e. sensing, surface enhanced Raman spectroscopy, photothermal ablation therapy of cancer, drug delivery or catalysis among others, where hollow nanostructures perform better than their solid counterparts, are also evaluated.

  20. Hollow metal nanostructures for enhanced plasmonics: synthesis, local plasmonic properties and applications

    Directory of Open Access Journals (Sweden)

    Genç Aziz

    2016-09-01

    Full Text Available Metallic nanostructures have received great attention due to their ability to generate surface plasmon resonances, which are collective oscillations of conduction electrons of a material excited by an electromagnetic wave. Plasmonic metal nanostructures are able to localize and manipulate the light at the nanoscale and, therefore, are attractive building blocks for various emerging applications. In particular, hollow nanostructures are promising plasmonic materials as cavities are known to have better plasmonic properties than their solid counterparts thanks to the plasmon hybridization mechanism. The hybridization of the plasmons results in the enhancement of the plasmon fields along with more homogeneous distribution as well as the reduction of localized surface plasmon resonance (LSPR quenching due to absorption. In this review, we summarize the efforts on the synthesis of hollow metal nanostructures with an emphasis on the galvanic replacement reaction. In the second part of this review, we discuss the advancements on the characterization of plasmonic properties of hollow nanostructures, covering the single nanoparticle experiments, nanoscale characterization via electron energy-loss spectroscopy and modeling and simulation studies. Examples of the applications, i.e. sensing, surface enhanced Raman spectroscopy, photothermal ablation therapy of cancer, drug delivery or catalysis among others, where hollow nanostructures perform better than their solid counterparts, are also evaluated.

  1. Manipulation of plasmonic resonances in graphene coated dielectric cylinders

    KAUST Repository

    Ge, Lixin

    2016-11-16

    Graphene sheets can support surface plasmon as the Dirac electrons oscillate collectively with electromagnetic waves. Compared with the surface plasmon in conventional metal (e.g., Ag and Au), graphene plasmonic owns many remarkable merits especially in Terahertz and far infrared frequencies, such as deep sub-wavelength, low loss, and high tunability. For graphene coated dielectric nano-scatters, localized surface plasmon (LSP)exist and can be excited under specific conditions. The LSPs are associated with the Mie resonance modes, leading to extraordinary large scattering and absorption cross section. In this work, we study systematically the optical scattering properties for graphene coated dielectric cylinders. It is found that the LSP can be manipulated by geometrical parameters and external electric gating. Generally, the resonance frequencies for different resonance modes are not the same. However, under proper design, we show that different resonance modes (e.g., dipole mode, quadruple mode etc.) can be excited at the same frequency. Thus, the scattering and absorption by graphene coated dielectric cylinders can indeed overcome the single channel limit. Our finding may open up new avenues in applications for the graphene-based THz optoelectronic devices.

  2. Detecting Plasmon Resonance Energy Transfer with Differential Interference Contrast Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Augspurger, Ashley E. [Ames Lab., Ames, IA (United States); Iowa State Univ., Ames, IA (United States); Stender, Anthony S. [Ames Lab., Ames, IA (United States); Iowa State Univ., Ames, IA (United States); Han, Rui [Ames Lab., Ames, IA (United States); Iowa State Univ., Ames, IA (United States); Fang, Ning [Ames Lab., Ames, IA (United States); Iowa State Univ., Ames, IA (United States)

    2013-12-30

    Gold nanoparticles are ideal probes for studying intracellular environments and energy transfer mechanisms due to their plasmonic properties. Plasmon resonance energy transfer (PRET) relies on a plasmonic nanoparticle to donate energy to a nearby resonant acceptor molecule, a process which can be observed due to the plasmonic quenching of the donor nanoparticle. In this study, a gold nanosphere was used as the plasmonic donor, while the metalloprotein cytochrome c was used as the acceptor molecule. Differential interference contrast (DIC) microscopy allows for simultaneous monitoring of complex environments and noble metal nanoparticles in real time. Using DIC and specially designed microfluidic channels, we were able to monitor PRET at the single gold particle level and observe the reversibility of PRET upon the introduction of phosphate-buffered saline to the channel. In an additional experiment, single gold particles were internalized by HeLa cells and were subsequently observed undergoing PRET as the cell hosts underwent morphological changes brought about by ethanol-induced apoptosis.

  3. Coherent Fano resonances in a plasmonic nanocluster enhance optical four-wave mixing

    Science.gov (United States)

    Zhang, Yu; Wen, Fangfang; Zhen, Yu-Rong; Nordlander, Peter; Halas, Naomi J.

    2013-01-01

    Plasmonic nanoclusters, an ordered assembly of coupled metallic nanoparticles, support unique spectral features known as Fano resonances due to the coupling between their subradiant and superradiant plasmon modes. Within the Fano resonance, absorption is significantly enhanced, giving rise to highly localized, intense near fields with the potential to enhance nonlinear optical processes. Here, we report a structure supporting the coherent oscillation of two distinct Fano resonances within an individual plasmonic nanocluster. We show how this coherence enhances the optical four-wave mixing process in comparison with other double-resonant plasmonic clusters that lack this property. A model that explains the observed four-wave mixing features is proposed, which is generally applicable to any third-order process in plasmonic nanostructures. With a larger effective susceptibility χ(3) relative to existing nonlinear optical materials, this coherent double-resonant nanocluster offers a strategy for designing high-performance third-order nonlinear optical media. PMID:23690571

  4. On the optical properties of plasmonic glasses

    Science.gov (United States)

    Antosiewicz, Tomasz J.; Langhammer, Christoph; Apell, S. Peter

    2014-12-01

    We report on the optical properties of plasmonic glasses which are metal-dielectric composites composed of metallic inclusions in a host dielectric medium. The investigated structures are of quasi-random nature, described by the pair correlation function, featuring a minimum center-to-center distance between metallic inclusions and long range randomness. Plasmonic glasses exhibiting short-range order only may be fabricated using bottom-up, self-assembly methods and have been utilized in a number of applications such as plasmonic sensing or plasmon-enhanced solar harvesting, and may be also employed for certain non-linear applications. It is therefore important to quantify their properties. Using theoretical methods we investigate optical of 1D, 2D, and 3D structures composed of amorphous distributions of metallic spheres. It is shown, that the response of the constituent element, i.e. the single sphere localized surface plasmon resonance, is modified by the scattered fields of the other spheres in such a way that its peak position, peak amplitude, and full-width at half-maximum exhibit damped oscillations. The oscillation amplitude is set by the particle density and for the peak position may vary by up to 0.3 eV in the optical regime. Using a modified coupled dipole approach we calculate the effective (average) polarizability of plasmonic glasses and discuss their spectra as a function of the dimensionality, angle of incidence and polarization, and the minimum center-to-center distance. The analytical model is complemented and validated by T-Matrix calculations of the optical cross-sections of amorphous arrays of metallic spheres obtained using a modification of the Random Sequential Adsorption algorithm for lines, surfaces, and volumes.

  5. Fano Resonance in an Electrically Driven Plasmonic Device

    Science.gov (United States)

    Vardi, Yuval; Cohen-Hoshen, Eyal; Shalem, Guy; Bar-Joseph, Israel

    Electrically driven plasmonic devices offer unique opportunities as a research tool and for practical applications. In such devices, current that flows across a metallic tunnel junction excites a plasmon, which gives rise to light emission. This local nature of the excitation allows access into ''dark'' modes, which are not easily excited by far field illumination. We present an electrically driven plasmonic device, based on a gold nanoparticle single-electron-transistor, and investigate the light emission due to the tunneling current. The applied voltage determines the emitted spectral lineshape, enables an excellent control of the plasmonic spectrum. We show that the use of this structure allows us to characterize the electrical properties of the two tunnel barriers, and determine their role in the light emission process. Furthermore, we find a Fano resonance, resulting from interference between the nanoparticle and electrodes dipoles. This resonance is seen due to the local nature of the excitation, and is manifested as a sharp asymmetrical spectral dip. We show that the spectral position of this resonance can be conveniently controlled by the design of the structural parameters. Such devices may be a step toward the realization of an on-chip nano-optical emitters and sensors.

  6. Coherent resonance of quantum plasmons in the graphene-gold cluster hybrid system.

    Science.gov (United States)

    Zhang, Kaibiao; Zhang, Hong; Li, Chikang

    2015-05-14

    Noble metal nanoparticles can modify the optical properties of graphene. Here we present a detailed theoretical analysis of the coherent resonance of quantum plasmons in the graphene-gold cluster hybrid system by using time dependent density functional theory (TDDFT). This plasmon coherent effect is mainly attributed to the electromagnetic field coupling between the graphene and the gold cluster. As a result, the optical response of the hybrid system exhibits a remarkably strong, selectable tuning and polarization dependent plasmon resonance enhanced in wide frequency regions. This investigation provides an improved understanding of the plasmon enhancement effect in a graphene-based photoelectric device.

  7. Large-area nanogap plasmon resonator arrays for plasmonics applications

    Science.gov (United States)

    Jin, Mingliang; van Wolferen, Henk; Wormeester, Herbert; van den Berg, Albert; Carlen, Edwin T.

    2012-07-01

    Large-area (~8000 mm2) Au nanogap plasmon resonator array substrates manufactured using maskless laser interference lithography (LIL) with high uniformity are presented. The periodically spaced subwavelength nanogap arrays are formed between adjacent nanopyramid (NPy) structures with precisely defined pitch and high length density (~1 km cm-2), and are ideally suited as scattering sites for surface enhanced Raman scattering (SERS), as well as refractive index sensing. The two-dimensional grid arrangement of NPy structures renders the excitation of the plasmon resonators minimally dependent on the incident polarization. The SERS average enhancement factor (AEF) has been characterized using over 30 000 individual measurements of benzenethiol (BT) chemisorbed on the Au NPy surfaces. From the 1(a1), βCCC + νCS ring mode (1074 cm-1) of BT on surfaces with pitch λg = 200 nm, AEF = 0.8 × 106 and for surfaces with λg = 500 nm, AEF = 0.3 × 107 from over 99% of the imaged spots. Maximum AEFs > 108 have been measured in both cases.

  8. Plasmon resonant liposomes for controlled drug delivery

    Science.gov (United States)

    Knights-Mitchell, Shellie S.; Romanowski, Marek

    2015-03-01

    Nanotechnology use in drug delivery promotes a reduction in systemic toxicity, improved pharmacokinetics, and better drug bioavailability. Liposomes continue to be extensively researched as drug delivery systems (DDS) with formulations such as Doxil® and Ambisome® approved by FDA and successfully marketed in the United States. However, the limited ability to precisely control release of active ingredients from these vesicles continues to challenge the broad implementation of this technology. Moreover, the full potential of the carrier to sequester drugs until it can reach its intended target has yet to be realized. Here, we describe a liposomal DDS that releases therapeutic doses of an anticancer drug in response to external stimulus. Earlier, we introduced degradable plasmon resonant liposomes. These constructs, obtained by reducing gold on the liposome surface, facilitate spatial and temporal release of drugs upon laser light illumination that ultimately induces an increase in temperature. In this work, plasmon resonant liposomes have been developed to stably encapsulate and retain doxorubicin at physiological conditions represented by isotonic saline at 37o C and pH 7.4. Subsequently, they are stimulated to release contents either by a 5o C increase in temperature or by laser illumination (760 nm and 88 mW/cm2 power density). Successful development of degradable plasmon resonant liposomes responsive to near-infrared light or moderate hyperthermia can provide a new delivery method for multiple lipophilic and hydrophilic drugs with pharmacokinetic profiles that limit clinical utility.

  9. Tunable plasmon resonances in anisotropic metal nanostructures

    NARCIS (Netherlands)

    Penninkhof, J.J.

    2006-01-01

    Coherent oscillations of free electrons in a metal, localized in a small volume or at an interface between a metal and a dielectric medium, have attracted a lot of attention in the past decades. These so-called surface plasmons have special optical properties that can be used in many applications ra

  10. Tunable plasmon resonances in anisotropic metal nanostructures

    NARCIS (Netherlands)

    Penninkhof, J.J.

    2006-01-01

    Coherent oscillations of free electrons in a metal, localized in a small volume or at an interface between a metal and a dielectric medium, have attracted a lot of attention in the past decades. These so-called surface plasmons have special optical properties that can be used in many applications

  11. Features of electromagnetic waves in a complex plasma due to surface plasmon resonances on macroparticles

    CERN Document Server

    Vladimirov, S V

    2015-01-01

    The dielectric properties of complex plasma containing either metal or dielectric spherical inclusions (macroparticles, dust) are investigated. We focus on surface plasmon resonances on the macroparticle surfaces and their effect on electromagnetic wave propagation. It is demonstrated that the presence of surface plasmon oscillations significantly modifies plasma electromagnetic properties by resonances and cutoffs in the effective permittivity. This leads to related branches of electromagnetic waves and to the wave band gaps. The results are discussed in the context of dusty plasma experiments.

  12. Plasmonic properties and applications of metallic nanostructures

    Science.gov (United States)

    Zhen, Yurong

    Plasmonic properties and the related novel applications are studied on various types of metallic nano-structures in one, two, or three dimensions. For 1D nanostructure, the motion of free electrons in a metal-film with nanoscale thickness is confined in its normal dimension and free in the other two. Describing the free-electron motion at metal-dielectric surfaces, surface plasmon polariton (SPP) is an elementary excitation of such motions and is well known. When further perforated with periodic array of holes, periodicity will introduce degeneracy, incur energy-level splitting, and facilitate the coupling between free-space photon and SPP. We applied this concept to achieve a plasmonic perfect absorber. The experimentally observed reflection dip splitting is qualitatively explained by a perturbation theory based on the above concept. If confined in 2D, the nanostructures become nanowires that intrigue a broad range of research interests. We performed various studies on the resonance and propagation of metal nanowires with different materials, cross-sectional shapes and form factors, in passive or active medium, in support of corresponding experimental works. Finite- Difference Time-Domain (FDTD) simulations show that simulated results agrees well with experiments and makes fundamental mode analysis possible. Confined in 3D, the electron motions in a single metal nanoparticle (NP) leads to localized surface plasmon resonance (LSPR) that enables another novel and important application: plasmon-heating. By exciting the LSPR of a gold particle embedded in liquid, the excited plasmon will decay into heat in the particle and will heat up the surrounding liquid eventually. With sufficient exciting optical intensity, the heat transfer from NP to liquid will undergo an explosive process and make a vapor envelop: nanobubble. We characterized the size, pressure and temperature of the nanobubble by a simple model relying on Mie calculations and continuous medium assumption. A

  13. Plasmonic metamaterial absorber for broadband manipulation of mechanical resonances

    Science.gov (United States)

    Zhu, Hai; Yi, Fei; Cubukcu, Ertugrul

    2016-11-01

    Metamaterials are artificial materials that exhibit unusual properties for electromagnetic and sound waves. The quanta, namely photons and phonons, of these waves interact resonantly with these exotic man-made materials enabling many applications. For instance, resonant light absorption in photonic metamaterials can efficiently convert optical energy into heat based on the photothermal effect. Here, we present a plasmonic metamaterial that simultaneously supports thermomechanically coupled optical and mechanical resonances for controlling mechanical damping with light. In this metamaterial absorber with voltage-tunable Fano resonances, we experimentally achieve optically pumped coherent mechanical oscillations based on a plasmomechanical parametric gain mechanism over an ∼4 THz bandwidth. Through the reverse effect, optical damping of mechanical resonance is also achieved. Our results provide a metamaterial-based approach for optical manipulation of the dynamics of mechanical oscillators.

  14. Hybrid plasmon photonic crystal resonance grating for integrated spectrometer biosensor.

    Science.gov (United States)

    Guo, Hong; Guo, Junpeng

    2015-01-15

    Using nanofabricated hybrid metal-dielectric nanohole array photonic crystal gratings, a hybrid plasmonic optical resonance spectrometer biosensor is demonstrated. The new spectrometer sensor technique measures plasmonic optical resonance from the first-order diffraction rather than via the traditional method of measuring optical resonance from transmission. The resonance spectra measured with the new spectrometer technique are compared with the spectra measured using a commercial optical spectrometer. It is shown that the new optical resonance spectrometer can be used to measure plasmonic optical resonance that otherwise cannot be measured with a regular optical spectrometer.

  15. A plasmonic fluid with dynamically tunable optical properties

    KAUST Repository

    Bhattacharjee, Rama Ranjan

    2009-01-01

    We report the first synthesis of a gold nanorod (GNR)-based nanocomposite that exhibits solid-like plasmonic properties while behaving in a liquid-like manner. Tuning the degree of GNR clustering controls the material\\'s responsiveness to external stimuli, such as mechanical shearing, due to the sensitivity of the localized surface plasmon resonance to interparticle interactions. © 2009 The Royal Society of Chemistry.

  16. Colloidal Plasmonic Titanium Nitride Nanoparticles: Properties and Applications

    CERN Document Server

    Guler, Urcan; Kildishev, Alexander V; Boltasseva, Alexandra; Shalaev, Vladimir M

    2014-01-01

    Optical properties of colloidal plasmonic titanium nitride nanoparticles are examined with an eye on their photothermal via transmission electron microscopy and optical transmittance measurements. Single crystal titanium nitride cubic nanoparticles with an average size of 50 nm exhibit plasmon resonance in the biological transparency window. With dimensions optimized for efficient cellular uptake, the nanoparticles demonstrate a high photothermal conversion efficiency. A self-passivating native oxide at the surface of the nanoparticles provides an additional degree of freedom for surface functionalization.

  17. Mapping of plasmonic resonances in nanotriangles

    Directory of Open Access Journals (Sweden)

    Simon Dickreuter

    2013-09-01

    Full Text Available Plasmonic resonances in metallic nano-triangles have been investigated by irradiating these structures with short laser pulses and imaging the resulting ablation and melting patterns. The triangular gold structures were prepared on Si substrates and had a thickness of 40 nm and a side length of ca. 500 nm. Irradiation was carried out with single femtosecond and picosecond laser pulses at a wavelength of 800 nm, which excited higher order plasmon modes in these triangles. The ablation distribution as well as the local melting of small parts of the nanostructures reflect the regions of large near-field enhancement. The observed patterns are reproduced in great detail by FDTD simulations with a 3-dimensional model, provided that the calculations are not based on idealized, but on realistic structures. In this realistic model, details like the exact shape of the triangle edges and the dielectric environment of the structures are taken into account. The experimental numbers found for the field enhancement are typically somewhat smaller than the calculated ones. The results demonstrate the caveats for FDTD simulations and the potential and the limitations of “near field photography” by local ablation and melting for the mapping of complex plasmon fields and their applications.

  18. Proximity Resonance and Localized Surface Plasmons

    Science.gov (United States)

    Liu, Bo; Heller, Eric

    2014-03-01

    The collective excitation of conduction electrons in subwavelength nanostructures is known as Localized Surface Plasmon(LSP)[1]. Such plasmon modes has been intensively studied using noble nanoparticles . More recently, the possibility of building terahertz metamaterials supporting such LSP modes has been explored in graphene microribbons and microdisks. Unlike Surface Plasmon Polaritons(SPPs) at metal-insulator interface, LSP can be directly excited by light illumination and holds promise for applications in ultrasensitive biosensing, nano-optical tweezers and improved photovoltaic devices. In this paper, we consider the interaction of two LSPs in the weak coupling regime and show how an effect similar to the proximity resonance in the quantum scattering theory) gives rise to an asymmetric(quadrupole) mode with increased damping rate. The existence of this asymmetric mode relies on a small phase retardation between the two LSPs. This phase retardation, though small, is key to both increased damping rate for the asymmetric mode and reduced damping rate for the symmetric mode. When this small phase retardation is removed by changing the polarization of the exciting light,we show that the asymmetric mode can not be excited and the symmetric mode shows increased damping.

  19. Plasmonic resonances in optomagnetic metamaterials based on double dot arrays.

    Science.gov (United States)

    Kravets, Vasyl G; Schedin, Fred; Taylor, Shaun; Viita, David; Grigorenko, Alexander N

    2010-05-10

    We study optical properties of optomagnetic metamaterials produced by regular arrays of double gold dots (nanopillars). Using combined data of spectroscopic ellipsometry, transmission and reflection measurements, we identify localized plasmon resonances of a nanopillar pair and measure their dependences on dot sizes. We formulate the necessary condition at which an effective field theory can be applied to describe optical properties of a composite medium and employ interferometry to measure phase shifts for our samples. A negative phase shift for transmitted green light coupled to an antisymmetric magnetic mode of a double-dot array is observed. (c) 2010 Optical Society of America.

  20. Colloidal Plasmonic Titanium Nitride Nanoparticles: Properties and Applications

    Directory of Open Access Journals (Sweden)

    Guler Urcan

    2015-01-01

    Full Text Available Optical properties of colloidal plasmonic titanium nitride nanoparticles are examined with an eye on their photothermal and photocatalytic applications via transmission electron microscopy and optical transmittance measurements. Single crystal titanium nitride cubic nanoparticles with an average size of 50 nm, which was found to be the optimum size for cellular uptake with gold nanoparticles [1], exhibit plasmon resonance in the biological transparency window and demonstrate a high absorption efficiency. A self-passivating native oxide at the surface of the nanoparticles provides an additional degree of freedom for surface functionalization. The titanium oxide shell surrounding the plasmonic core can create new opportunities for photocatalytic applications.

  1. Photothermal probing of plasmonic hotspots with nanomechanical resonator

    DEFF Research Database (Denmark)

    Schmid, Silvan; Wu, Kaiyu; Rindzevicius, Tomas

    2014-01-01

    Plasmonic nanostructures (hotspots) are key components e.g. in plasmon-enhanced spectroscopy, plasmonic solar cells, or as nano heat sources. The characterization of single hotspots is still challenging due to a lack of experimental tools. We present the direct photothermal probing and mapping...... of single plasmonic nanoslits via the thermally induced detuning of nanomechanical string resonators. A maximum relative frequency detuning of 0.5 % was measured for a single plasmonic nanoslit for a perpendicularly polarized laser with a power of 1350 nW. Finally, we show the photothermal scan over...

  2. Plasmonic colour generation

    DEFF Research Database (Denmark)

    Kristensen, Anders; Yang, Joel K. W.; Bozhevolnyi, Sergey I.

    2016-01-01

    Plasmonic colours are structural colours that emerge from resonant interactions between light and metallic nanostructures. The engineering of plasmonic colours is a promising, rapidly emerging research field that could have a large technological impact. We highlight basic properties of plasmonic...

  3. Plasmon resonance energy transfer and plexcitonic solar cell.

    Science.gov (United States)

    Nan, Fan; Ding, Si-Jing; Ma, Liang; Cheng, Zi-Qiang; Zhong, Yu-Ting; Zhang, Ya-Fang; Qiu, Yun-Hang; Li, Xiaoguang; Zhou, Li; Wang, Qu-Quan

    2016-08-11

    Plasmon-mediated energy transfer is highly desirable in photo-electronic nanodevices, but the direct injection efficiency of "hot electrons" in plasmonic photo-detectors and plasmon-sensitized solar cells (plasmon-SSCs) is poor. On another front, Fano resonance induced by strong plasmon-exciton coupling provides an efficient channel of coherent energy transfer from metallic plasmons to molecular excitons, and organic dye molecules have a much better injection efficiency in exciton-SSCs than "hot electrons". Here, we investigate enhanced light-harvesting of chlorophyll-a molecules strongly coupled to Au nanostructured films via Fano resonance. The enhanced local field and plasmon resonance energy transfer are experimentally revealed by monitoring the ultrafast dynamical processes of the plexcitons and the photocurrent flows of the assembled plexciton-SSCs. By tuning the Fano factor and anti-resonance wavelengths, we find that the local field is largely enhanced and the efficiency of plexciton-SSCs consisting of ultrathin TiO2 films is significantly improved. Most strikingly, the output power of the plexciton-SSCs is much larger than the sum of those of the individual plasmon- and exciton-SSCs. Our observations provide a practical approach to monitor energy and electron transfer in plasmon-exciton hybrids at a strong coupling regime and also offer a new strategy to design photovoltaic nanodevices.

  4. Magnetic Plasmon Sensing in Twisted Split-Ring Resonators

    Directory of Open Access Journals (Sweden)

    J. X. Cao

    2012-01-01

    Full Text Available We studied the sensing properties of stereo-SRRs metamaterials composed from two twisted split-ring resonators (SRRs. Due to the strong hybridization effect in the system, the polarization state of the transmitted wave is greatly changed at resonances. Since the stereo-SRRs structure is strongly coupled to the surrounding medium, the polarization change of the transmitted waves is quite sensitive to the refractive index change of the environment medium. The polarization ratio PRtran = Ty/Tx is used as sensing parameter and its figure of merit can reach 22.3 at the hybridized magnetic plasmon resonance. The results showed that the stereo-SRRs metamaterial can be applied to optical sensors an or other related field.

  5. Formation of metal nanoparticles in silicon nanopores: Plasmon resonance studies

    Science.gov (United States)

    Polisski, S.; Goller, B.; Heck, S. C.; Maier, S. A.; Fujii, M.; Kovalev, D.

    2011-01-01

    We present a method for the formation of noble metal nanoparticle ensembles in nanostructured silicon. The key idea is based on the unique property of the large reduction potential of extended internal hydrogen-terminated porous silicon surfaces. The process of metal nanoparticle formation in porous silicon was experimentally traced using their optical plasmon resonance response. We also demonstrate that bimetallic compounds can be formed in porous silicon and that their composition can be controlled using this technique. Experimental results were found to contradict partially with considerations based on Mie theory.

  6. Surface plasmon resonance-enabled antibacterial digital versatile discs

    Science.gov (United States)

    Dou, Xuan; Chung, Pei-Yu; Jiang, Peng; Dai, Jianli

    2012-02-01

    We report the achievement of effective sterilization of exemplary bacteria including Escherichia coli and Geobacillus stearothermophilus spores on a digital versatile disc (DVD). The spiral arrangement of aluminum-covered pits generates strong surface plasmon resonance (SPR) absorption of near-infrared light, leading to high surface temperature that could even damage the DVD plastics. Localized protein denaturation and high sterilization efficiency have been demonstrated by using a fluorescence microscope and cell cultures. Numerical simulations have also been conducted to model the SPR properties and the surface temperature distribution of DVDs under laser illumination. The theoretical predictions agree reasonably well with the experimental results.

  7. Surface plasmon resonance biosensors: advances and applications

    Science.gov (United States)

    Homola, Jirí

    2009-10-01

    Surface plasmon resonance (SPR) biosensors represent the most advanced label-free optical affinity biosensor technology. In the last decade numerous SPR sensor platforms have been developed and applied in the life sciences and bioanalytics. This contribution reviews the state of the art in the development of SPR (bio)sensor technology and presents selected results of research into SPR biosensors at the Institute of Photonics and Electronics, Prague. The developments discussed in detail include a miniature fiber optic SPR sensor for localized measurements, a compact SPR sensor for field use and a multichannel SPR sensor for high-throughput screening. Examples of applications for the detection of analytes related to medical diagnostics (biomarkers, hormones, antibodies), environmental monitoring (endocrine disrupting compounds), and food safety (pathogens and toxins) are given.

  8. Toxin Detection by Surface Plasmon Resonance

    Directory of Open Access Journals (Sweden)

    2009-02-01

    Full Text Available Significant efforts have been invested in the past years for the development of analytical methods for fast toxin detection in food and water. Immunochemical methods like ELISA, spectroscopy and chromatography are the most used in toxin detection. Different methods have been linked, e.g. liquid chromatography and mass spectrometry (LC-MS, in order to detect as low concentrations as possible. Surface plasmon resonance (SPR is one of the new biophysical methods which enables rapid toxin detection. Moreover, this method was already included in portable sensors for on-site determinations. In this paper we describe some of the most common methods for toxin detection, with an emphasis on SPR.

  9. Generalized Landau damping due to multi-plasmon resonances

    CERN Document Server

    Brodin, Gert; Zamanian, Jens

    2016-01-01

    We study wave-particle interaction of Langmuir waves in a fully degenerate plasma using the Wigner-Moyal equation. As is well known, in the short wavelength regime the resonant velocity is shifted from the phase velocity due to the finite energy and momentum of individual plasmon quanta. In the present work we focus on the case when the resonant velocity lies outside the background distribution, i.e. when it is larger than the Fermi velocity. Going beyond the linearized theory we show that we can still have nonlinear wave-particle damping associated with multi-plasmon resonances. Sets of evolution equations are derived for the case of two-plasmon resonance and for the case of three-plasmon resonance. The damping rates of the Langmuir waves are deduced for both cases, and the implications of the results are discussed.

  10. On the mechanism of electrochemical modulation of plasmonic resonances

    Science.gov (United States)

    Shao, L.-H.; Ruther, M.; Linden, S.; Wegener, M.; Weissmüller, J.

    2012-09-01

    Recent electrochemical experiments on gold-based photonic metamaterials have shown a sizable reversible tuning and modulation of plasmonic resonances. Here, we study the mechanism of the electrochemical modulation by measuring the change of the resonance transmittance and resonance frequency during underpotential deposition of Pb, Cu, and electrosorption of OH. The electric resistance change of the resonators is identified as decisive for the resonance transmittance change, while the space-charge layer at the metal surface shifts the resonance frequency.

  11. Nano Sensing and Energy Conversion Using Surface Plasmon Resonance (SPR

    Directory of Open Access Journals (Sweden)

    Iltai (Isaac Kim

    2015-07-01

    Full Text Available Nanophotonic technique has been attracting much attention in applications of nano-bio-chemical sensing and energy conversion of solar energy harvesting and enhanced energy transfer. One approach for nano-bio-chemical sensing is surface plasmon resonance (SPR imaging, which can detect the material properties, such as density, ion concentration, temperature, and effective refractive index in high sensitivity, label-free, and real-time under ambient conditions. Recent study shows that SPR can successfully detect the concentration variation of nanofluids during evaporation-induced self-assembly process. Spoof surface plasmon resonance based on multilayer metallo-dielectric hyperbolic metamaterials demonstrate SPR dispersion control, which can be combined with SPR imaging, to characterize high refractive index materials because of its exotic optical properties. Furthermore, nano-biophotonics could enable innovative energy conversion such as the increase of absorption and emission efficiency and the perfect absorption. Localized SPR using metal nanoparticles show highly enhanced absorption in solar energy harvesting. Three-dimensional hyperbolic metamaterial cavity nanostructure shows enhanced spontaneous emission. Recently ultrathin film perfect absorber is demonstrated with the film thickness is as low as ~1/50th of the operating wavelength using epsilon-near-zero (ENZ phenomena at the wavelength close to SPR. It is expected to provide a breakthrough in sensing and energy conversion applications using the exotic optical properties based on the nanophotonic technique.

  12. All-plasmonic switching based on thermal nonlinearity in a polymer plasmonic microring resonator

    Science.gov (United States)

    Perron, David; Wu, Marcelo; Horvath, Cameron; Bachman, Daniel; van, Vien

    2011-07-01

    We experimentally investigated thermal nonlinear effects in a hybrid Au/SiO2/SU-8 plasmonic microring resonator for nonlinear switching. Large ohmic loss in the metal layer gave rise to a high rate of light-to-heat conversion in the plasmonic waveguide, causing an intensity-dependent thermo-optic shift in the microring resonance. We obtained 30 times larger resonance shift in the plasmonic microring than in a similar SU-8 dielectric microring. Using an in-plane pump-and-probe configuration, we also demonstrated all-plasmonic nonlinear switching in the plasmonic microring with an on--off switching contrast of 4dB over 50mW input power.

  13. Electron beam imaging and spectroscopy of plasmonic nanoantenna resonances

    NARCIS (Netherlands)

    Vesseur, P.C.

    2011-01-01

    Nanoantennas are metal structures that provide strong optical coupling between a nanoscale volume and the far field. This coupling is mediated by surface plasmons, oscillations of the free electrons in the metal. Increasing the control over the resonant plasmonic field distribution opens up a wide r

  14. Guidelines for designing 2D and 3D plasmonic stub resonators

    CERN Document Server

    Naghizadeh, Solmaz

    2016-01-01

    In this work we compare the performance of plasmonic waveguide integrated stub resonators based on 2D metal-dielectric-metal (MDM) and 3D slot-waveguide (SWG) geometries. We show that scattering matrix theory can be extended to 3D devices, and by employing scattering matrix theory we provide the guidelines for designing plasmonic 2D and 3D single-stub and double-stub resonators with a desired spectral response at the design wavelength. We provide transmission maps of 2D and 3D double-stub resonators versus stub lengths, and we specify the different regions on these maps that result in a minimum, a maximum or a plasmonically induced transparency (PIT) shape in the transmission spectrum. Radiation loss from waveguide terminations leads to a degradation of the 3D slot-waveguide based resonators. We illustrate improved waveguide terminations that boost resonator properties. We verify our results with 3D FDTD simulations.

  15. Ultracompact plasmonic racetrack resonators in metal-insulator-metal waveguides

    CERN Document Server

    Han, Zhanghua

    2010-01-01

    Among various plasmonic waveguides, the metal-insulator-metal (MIM) type is the most promising for true subwavelength photonic integration. To date, many photonic devices based on MIM waveguides have been investigated, including resonators. However, most of the reported MIM ring resonators suffer from low extinction ratios. In this paper, we present a comprehensive analysis of the intrinsic reasons for the low performance of MIM ring resonators, and give the analytical transmission relation for a universal all-pass ring resonator which has coupling loss. Based on the analysis we propose the plasmonic racetrack resonators in MIM waveguides and show that the performance can be greatly improved.

  16. Nanostructure-enhanced surface plasmon resonance imaging (Conference Presentation)

    Science.gov (United States)

    Špašková, Barbora; Lynn, Nicholas S.; Slabý, Jiří Bocková, Markéta; Homola, Jiří

    2017-06-01

    There remains a need for the multiplexed detection of biomolecules at extremely low concentrations in fields of medical diagnostics, food safety, and security. Surface plasmon resonance imaging is an established biosensing approach in which the measurement of the intensity of light across a sensor chip is correlated with the amount of target biomolecules captured by the respective areas on the chip. In this work, we present a new approach for this method allowing for enhanced bioanalytical performance via the introduction of nanostructured sensing chip and polarization contrast measurement, which enable the exploitation of both amplitude and phase properties of plasmonic resonances on the nanostructures. Here we will discuss a complex theoretical analysis of the sensor performance, whereby we investigate aspects related to both the optical performance as well as the transport of the analyte molecules to the functionalized surfaces. This analysis accounts for the geometrical parameters of the nanostructured sensing surface, the properties of functional coatings, and parameters related to the detection assay. Based on the results of the theoretical analysis, we fabricated sensing chips comprised of arrays of gold nanoparticles (by electron-beam lithography), which were modified by a biofunctional coating to allow for the selective capturing of the target biomolecules in the regions with high sensitivity. In addition, we developed a compact optical reader with an integrated microfluidic cell, allowing for the measurement from 50 independent sensing channels. The performance of this biosensor is demonstrated through the sensitive detection of short oligonucleotides down to the low picomolar level.

  17. Slow-plasmon resonant nano-strip antennas

    DEFF Research Database (Denmark)

    Søndergaard, Thomas; Beermann, Jonas; Boltasseva, Alexandra

    2008-01-01

    Resonant scattering by gold nanostrip antennas due to constructive interference of counterpropagating slow surface plasmon polaritons SPPs is analyzed, including the quasistatic limit of ultrasmall antennas, and experimentally demonstrated. The phase of slow SPP reflection by strip ends is found...

  18. Slow-plasmon resonant-nanostrip antennas: Analysis and demonstration

    DEFF Research Database (Denmark)

    Søndergaard, Thomas; Beermann, J.; Boltasseva, Alexandra;

    2008-01-01

    Resonant scattering by gold nanostrip antennas due to constructive interference of counterpropagating slow surface plasmon polaritons (SPPs) is analyzed, including the quasistatic limit of ultrasmall antennas, and experimentally demonstrated. The phase of slow SPP reflection by strip ends is found...

  19. Plasmonic Biosensors

    OpenAIRE

    Hill, Ryan T.

    2014-01-01

    The unique optical properties of plasmon resonant nanostructures enable exploration of nanoscale environments using relatively simple optical characterization techniques. For this reason, the field of plasmonics continues to garner the attention of the biosensing community. Biosensors based on propagating surface plasmon resonances (SPRs) in films are the most well-recognized plasmonic biosensors, but there is great potential for the new, developing technologies to surpass the robustness and ...

  20. Interacting Dark Resonances with Plasmonic Meta-Molecules

    Science.gov (United States)

    2014-09-17

    Interacting dark resonances with plasmonic meta-molecules Pankaj K. Jha,1 Michael Mrejen,1 Jeongmin Kim,1 Chihhui Wu,1 Xiaobo Yin,1 Yuan Wang,1 and...accepted 6 September 2014; published online 17 September 2014) Dark state physics has led to a variety of remarkable phenomena in atomic physics, quantum...optics, and information theory. Here, we investigate interacting dark resonance type physics in multi-layered plasmonic meta-molecules. We

  1. Broadband converging plasmon resonance at a conical nanotip

    OpenAIRE

    Wang, Yunshan; Plouraboué, Franck; Chang, Hsueh-Chia

    2013-01-01

    International audience; We propose an analytical theory which predicts that Converging Plasmon Resonance (CPR) at conical nanotips exhibits a red-shifted and continuous band of resonant frequencies and suggests potential application of conical nanotips in various fields, such as plasmonic solar cells, photothermal therapy, tip-enhanced Raman and other spectroscopies. The CPR modes exhibit superior confinement and ten times broader scattering bandwidth over the entire solar spectrum than smoot...

  2. Multi-hole Optical Fiber Surface Plasmon Resonance Sensor

    Energy Technology Data Exchange (ETDEWEB)

    Guan Chunying; Wang Yang; Yuan Libo, E-mail: cyguan@163.com [College of Science, Harbin Engineering University, Harbin 150001 (China)

    2011-02-01

    A microstructured-fiber containing six large air holes is proposed to construct the surface plasmon resonance (SPR) sensor. The finite element method is used to analyze characteristics of the surface plasmon resonance sensor. The effects of the thickness of metal films, pitch between air holes, diameter of air hole, and refractive index of liquid on the resonance wavelength are elucidated. The results show that the resonance wavelength is sensitive to the thickness of metal film and refractive index of liquid, while the resonance wavelength doesn't change basically when the pitch between air holes and diameter of air holes vary. The proposed surface plasmon resonance sensor exhibits high sensitivity up to 10{sup -4}.

  3. Spectrometer sensor using patterned nano-structure plasmon resonance grating (Conference Presentation)

    Science.gov (United States)

    Guo, Hong; Tian, Xueli; Guo, Junpeng

    2016-03-01

    Localized surface plasmon resonance has been extensively investigated for biochemical sensor applications. In traditional localized surface plasmon resonance biosensors, resonance spectra were measured in the reflection or transmission from the nanostructure devices. In this work, we demonstrate a new surface plasmon resonance sensor platform with which the localized surface plasmon resonance and shift were measured by using a CCD imager instead of using an optical spectrometer. In additional to the metal nanostructures which support localized plasmon resonance, we pattern the nanostructures into diffraction gratings with super-wavelength grating periods. The nanostructure diffraction gratings support localized plasmon resonance and also diffract localized plasmon resonance radiations into non-zeroth order diffractions. Plasmon resonance spectrum and shift are measured with a CCD imager in one of the diffraction orders. The new plasmon resonance spectrometer sensor combines the functions of sensing and spectral analysis into one apparatus and is capable of real-time visualization of the biochemical bonding process with an imager.

  4. Frequency-selective propagation of localized spoof surface plasmons in a graded plasmonic resonator chain

    Science.gov (United States)

    Gao, Zhen; Gao, Fei; Shastri, Kunal Krishnaraj; Zhang, Baile

    2016-01-01

    Localized spoof surface plasmon polaritons (spoof-SPPs) in a graded spoof-plasmonic resonator chain with linearly increasing spacing are experimentally investigated at microwave frequencies. Transmission measurements and direct near-field mappings on this graded chain show that the propagation of localized spoof-SPPs can be cutoff at different positions along the graded chain under different frequencies due to the graded coupling between adjacent resonators. This mechanism can be used to guide localized spoof-SPPs in the graded chain to specific positions depending on the frequency and thereby implement a device that can work as a selective switch in integrated plasmonic circuits. PMID:27149656

  5. Plasmon resonances in semiconductor materials for detecting photocatalysis at the single-particle level.

    Science.gov (United States)

    Yan, Jiahao; Lin, Zhaoyong; Ma, Churong; Zheng, Zhaoqiang; Liu, Pu; Yang, Guowei

    2016-08-11

    Hot carriers, generated via the non-radiative decay of localized surface plasmon, can be utilized in photovoltaic and photocatalytic devices. In recent years, most studies have focused on conventional plasmon materials like Au and Ag. However, they suffer from several drawbacks like low energy of the generated hot carriers and a high charge-carrier recombination rate. To resolve these problems, here, we propose the plasmon resonances in heavily self-doped titanium oxide (TiO1.67) to realize effective hot carrier generation. Since the plasmon resonant energy of TiO1.67 nanoparticles (2.56 eV) is larger than the bandgap (2.15 eV), plasmon resonances through interband transition can realize both the generation and separation of hot carriers and bring a new strategy for visible-light photodegradation. The photodegradation rate for methyl orange was about 0.034 min(-1). More importantly, the combination of plasmonic and catalytic properties makes it feasible to investigate the degradation process of different materials and different structures at the single particle level in situ. By detecting the scattering shift, we demonstrated that the TiO1.67 dimer (Δλ/ΔλRIU = 0.16) possesses a higher photodegradation rate than an individual nanoparticle (Δλ/ΔλRIU = 0.09). We hope this finding may be a beginning, paving the way toward the development of semiconductor plasmonic materials for new applications beyond noble metals.

  6. Strong and Coherent Coupling of a Plasmonic Nanoparticle to a Subwavelength Fabry-Pérot Resonator.

    Science.gov (United States)

    Konrad, Alexander; Kern, Andreas M; Brecht, Marc; Meixner, Alfred J

    2015-07-08

    A major aim in experimental nano- and quantum optics is observing and controlling the interaction between light and matter on a microscopic scale. Coupling molecules or atoms to optical microresonators is a prominent method to alter their optical properties such as luminescence spectra or lifetimes. Until today strong coupling of optical resonators to such objects has only been observed with atom-like systems in high quality resonators. We demonstrate first experiments revealing strong coupling between individual plasmonic gold nanorods (GNR) and a tunable low quality resonator by observing cavity-length-dependent nonlinear dephasing and spectral shifts indicating spectral anticrossing of the luminescent coupled system. These phenomena and experimental results can be described by a model of two coupled oscillators representing the plasmon resonance of the GNR and the optical fields of the resonator. The presented reproducible and accurately tunable resonator allows us to precisely control the optical properties of individual particles.

  7. Fano-like interference of plasmon resonances at a single rod-shaped nanoantenna

    OpenAIRE

    López-Tejeira, F.; Paniagua-Domínguez, R.; Rodríguez-Oliveros, R.; Sánchez-Gil, J. A.

    2011-01-01

    Single metallic nanorods acting as half-wave antennas in the optical range exhibit an asymmetric, multi-resonant scattering spectrum that strongly depends on both their length and dielectric properties. Here we show that such spectral features can be easily understood in terms of Fano-like interference between adjacent plasmon resonances. On the basis of analytical and numerical results for different geometries, we demonstrate that Fano resonances may appear for such single-particle nanoanten...

  8. Synthesis and characterization of plasmonic resonant guided wave networks.

    Science.gov (United States)

    Burgos, Stanley P; Lee, Ho W; Feigenbaum, Eyal; Briggs, Ryan M; Atwater, Harry A

    2014-06-11

    Composed of optical waveguides and power-splitting waveguide junctions in a network layout, resonant guided wave networks (RGWNs) split an incident wave into partial waves that resonantly interact within the network. Resonant guided wave networks have been proposed as nanoscale distributed optical networks (Feigenbaum and Atwater, Phys. Rev. Lett. 2010, 104, 147402) that can function as resonators and color routers (Feigenbaum et al. Opt. Express 2010, 18, 25584-25595). Here we experimentally characterize a plasmonic resonant guided wave network by demonstrating that a 90° waveguide junction of two v-groove channel plasmon polariton (CPP) waveguides operates as a compact power-splitting element. Combining these plasmonic power splitters with CPP waveguides in a network layout, we characterize a prototype plasmonic nanocircuit composed of four v-groove waveguides in an evenly spaced 2 × 2 configuration, which functions as a simple, compact optical logic device at telecommunication wavelengths, routing different wavelengths to separate transmission ports due to the resulting network resonances. The resonant guided wave network exhibits the full permutation of Boolean on/off values at two output ports and can be extended to an eight-port configuration, unlike other photonic crystal and plasmonic add/drop filters, in which only two on/off states are accessible.

  9. Culturing photosynthetic bacteria through surface plasmon resonance

    Science.gov (United States)

    Ooms, Matthew D.; Bajin, Lauren; Sinton, David

    2012-12-01

    In this work, cultivation of photosynthetic microbes in surface plasmon enhanced evanescent fields is demonstrated. Proliferation of Synechococcus elongatus was obtained on gold surfaces excited with surface plasmons. Excitation over three days resulted in 10 μm thick biofilms with maximum cell volume density of 20% vol/vol (2% more total accumulation than control experiments with direct light). Collectively, these results indicate the ability to (1) excite surface-bound cells using plasmonic light fields, and (2) subsequently grow thick biofilms by coupling light from the surface. Plasmonic light delivery presents opportunities for high-density optofluidic photobioreactors for microalgal analysis and solar fuel production.

  10. Culturing photosynthetic bacteria through surface plasmon resonance

    Energy Technology Data Exchange (ETDEWEB)

    Ooms, Matthew D.; Bajin, Lauren; Sinton, David [Department of Mechanical and Industrial Engineering and Centre for Sustainable Energy, University of Toronto, Toronto M5S 3G8 (Canada)

    2012-12-17

    In this work, cultivation of photosynthetic microbes in surface plasmon enhanced evanescent fields is demonstrated. Proliferation of Synechococcus elongatus was obtained on gold surfaces excited with surface plasmons. Excitation over three days resulted in 10 {mu}m thick biofilms with maximum cell volume density of 20% vol/vol (2% more total accumulation than control experiments with direct light). Collectively, these results indicate the ability to (1) excite surface-bound cells using plasmonic light fields, and (2) subsequently grow thick biofilms by coupling light from the surface. Plasmonic light delivery presents opportunities for high-density optofluidic photobioreactors for microalgal analysis and solar fuel production.

  11. Plasmon resonances in atomic-scale gaps

    CERN Document Server

    Kern, Johannes; Tarakina, Nadezda V; Häckel, Tim; Emmerling, Monika; Kamp, Martin; Huang, Jer-Shing; Biagioni, Paolo; Prangsma, Jord C; Hecht, Bert

    2011-01-01

    Gap modes in resonant plasmonic nanostructures exhibit optical fields whose spatial confinement and near-field enhancement strongly increases for smaller gaps[1]. In the context of augmented light-matter interaction, gap modes are of high interest for various applications such as single-emitter spectroscopy[2-4], quantum optics[5,6], extreme nonlinear optics[7,8], efficient optical switching[9], optical trapping10, and molecular opto-electronics[11]. By means of reproducible self-assembly we have obtained side-by-side aligned gold nanorod dimers with robust gaps reaching well below 0.5 nm. For such atomic-scale gaps extreme splitting of the symmetric and anti-symmetric dimer eigenmodes of more than 800 meV is observed in white-light scattering experiments. Besides providing evidence for atomic-scale gap modes at visible wavelengths with correspondingly small mode volumes and strong field enhancement, our experimental results can serve as a benchmark for electromagnetic modeling beyond local Maxwell theory[12,...

  12. Tunable plasmonic resonance of gallium nanoparticles by thermal oxidation at low temperaturas

    Science.gov (United States)

    Catalán-Gómez, S.; Redondo-Cubero, A.; Palomares, F. J.; Nucciarelli, F.; Pau, J. L.

    2017-10-01

    The effect of the oxidation of gallium nanoparticles (Ga NPs) on their plasmonic properties is investigated. Discrete dipole approximation has been used to study the wavelength of the out-of-plane localized surface plasmon resonance in hemispherical Ga NPs, deposited on silicon substrates, with oxide shell (Ga2O3) of different thickness. Thermal oxidation treatments, varying temperature and time, were carried out in order to increase experimentally the Ga2O3 shell thickness in the NPs. The optical, structural and chemical properties of the oxidized NPs have been studied by spectroscopic ellipsometry, scanning electron microscopy, grazing incidence x-ray diffraction and x-ray photoelectron spectroscopy. A clear redshift of the peak wavelength is observed, barely affecting the intensity of the plasmon resonance. A controllable increase of the Ga2O3 thickness as a consequence of the thermal annealing is achieved. In addition, simulations together with ellipsometry results have been used to determine the oxidation rate, whose kinetics is governed by a logarithmic dependence. These results support the tunable properties of the plasmon resonance wavelength in Ga NPs by thermal oxidation at low temperatures without significant reduction of the plasmon resonance intensity.

  13. Controlling light with resonant plasmonic nanostructures

    NARCIS (Netherlands)

    Waele, R. de

    2009-01-01

    Plasmons are collective oscillations of free electrons in a metal. At optical frequencies plasmons enable nanoscale confinement of light in metal nanostructures. This ability has given rise to many applications in e.g. photothermal cancer treatment, light trapping in photovoltaic cells, and sensing.

  14. Broadband converging plasmon resonance at a conical nanotip.

    Science.gov (United States)

    Wang, Yunshan; Plouraboue, Franck; Chang, Hsueh-Chia

    2013-03-11

    We propose an analytical theory which predicts that Converging Plasmon Resonance (CPR) at conical nanotips exhibits a red-shifted and continuous band of resonant frequencies and suggests potential application of conical nanotips in various fields, such as plasmonic solar cells, photothermal therapy, tip-enhanced Raman and other spectroscopies. The CPR modes exhibit superior confinement and ten times broader scattering bandwidth over the entire solar spectrum than smooth nano-structures. The theory also explicitly connects the optimal angles and resonant optical frequencies to the material permittivities, with a specific optimum half angle that depends only on the real permittivity for high-permittivity and low-loss materials.

  15. Plasmon ruler with gold nanorod dimers: utilizing the second-order resonance

    CERN Document Server

    Le, Anton T; Dubrovina, Natalia; Lupu, Anatole; Fedyanin, Andrey A

    2014-01-01

    The idea of utilizing the second-order plasmon resonance of the gold nanorod {\\pi}-dimers for plasmon rulers is introduced. We report on a qualitatively different dependence of the plasmon resonance shift on the interparticle distance for the first- and second-order longitudinal modes, extending the working range of plasmon rulers up to the distance values of 400 nm.

  16. Molecular Plasmonics

    Science.gov (United States)

    Wilson, Andrew J.; Willets, Katherine A.

    2016-06-01

    In this review, we survey recent advances in the field of molecular plasmonics beyond the traditional sensing modality. Molecular plasmonics is explored in the context of the complex interaction between plasmon resonances and molecules and the ability of molecules to support plasmons self-consistently. First, spectroscopic changes induced by the interaction between molecular and plasmonic resonances are discussed, followed by examples of how tuning molecular properties leads to active molecular plasmonic systems. Next, the role of the position and polarizability of a molecular adsorbate on surface-enhanced Raman scattering signals is examined experimentally and theoretically. Finally, we introduce recent research focused on using molecules as plasmonic materials. Each of these examples is intended to highlight the role of molecules as integral components in coupled molecule-plasmon systems, as well as to show the diversity of applications in molecular plasmonics.

  17. Plasmonic metalens based on coupled resonators for focusing of surface plasmons

    KAUST Repository

    Xu, Quan

    2016-11-29

    As an essential functionality, flexible focusing of surface plasmons (SPs) is of particular interest in nonlinear optics and highly integrated plasmonic circuitry. Here, we developed a versatile plasmonic metalens, a metasurface comprised of coupled subwavelength resonators, whose optical responses exhibit a remarkable feature of electromagnetically induced transparency (EIT). We demonstrate numerically and experimentally how a proper spatial design of the unit elements steers SPs to arbitrary foci based on the holographic principles. More specifically, we show how to control the interaction between the constituent EIT resonators to efficiently manipulate the focusing intensity of SPs. We also demonstrated that the proposed metalens is capable of achieving frequency division multiplexing. The power and simplicity of the proposed design would offer promising opportunities for practical plasmonic devices.

  18. Plasmonic metalens based on coupled resonators for focusing of surface plasmons

    Science.gov (United States)

    Xu, Quan; Zhang, Xueqian; Xu, Yuehong; Li, Quan; Li, Yanfeng; Ouyang, Chunmei; Tian, Zhen; Gu, Jianqiang; Zhang, Wentao; Zhang, Xixiang; Han, Jiaguang; Zhang, Weili

    2016-11-01

    As an essential functionality, flexible focusing of surface plasmons (SPs) is of particular interest in nonlinear optics and highly integrated plasmonic circuitry. Here, we developed a versatile plasmonic metalens, a metasurface comprised of coupled subwavelength resonators, whose optical responses exhibit a remarkable feature of electromagnetically induced transparency (EIT). We demonstrate numerically and experimentally how a proper spatial design of the unit elements steers SPs to arbitrary foci based on the holographic principles. More specifically, we show how to control the interaction between the constituent EIT resonators to efficiently manipulate the focusing intensity of SPs. We also demonstrated that the proposed metalens is capable of achieving frequency division multiplexing. The power and simplicity of the proposed design would offer promising opportunities for practical plasmonic devices.

  19. Young's modulus measurement based on surface plasmon resonance

    Science.gov (United States)

    Lotfalian, Ali; Jandaghian, Ali; Saghafifar, Hossein; Mohajerani, Ezzedin

    2017-09-01

    In this paper, Young's modulus of polymers is experimentally measured using pressure sensors based on surface plasmon polariton. Theoretical relationships of changes in polymer reflective index due to applying pressure are investigated as well as the dependence of surface plasmon to the polymer reflective index. For the purpose of investigating the effects of the layers thicknesses, numerical simulation is performed using transfer matrix. Changes in resonance angle of surface plasmon due to applying pressure are experimentally studied as well. Practically, a sample of silicon rubber, as one of the most widely-used polymers, is checked and its Young's modulus is measured as 8.1 MPa.

  20. Interferometric Measurement of Far Infrared Plasmons via Resonant Homodyne Mixing

    CERN Document Server

    Dyer, Gregory C; Allen, S James; Grine, Albert D; Bethke, Don; Reno, John L; Shaner, Eric A

    2016-01-01

    We present an electrically tunable terahertz two dimensional plasmonic interferometer with an integrated detection element that down converts the terahertz fields to a DC signal. The integrated detector utilizes a resonant plasmonic homodyne mixing mechanism that measures the component of the plasma waves in-phase with an excitation field functioning as the local oscillator. Plasmonic interferometers with two independently tuned paths are studied. These devices demonstrate a means for developing a spectrometer-on-a-chip where the tuning of electrical length plays a role analogous to that of physical path length in macroscopic Fourier transform interferometers.

  1. Resonant enhancement of Raman scattering in metamaterials with hybrid electromagnetic and plasmonic resonances

    CERN Document Server

    Guddala, Sriram; Ramakrishna, S Anantha

    2016-01-01

    A tri-layer metamaterial perfect absorber of light, consisting of (Al/ZnS/Al) films with the top aluminium layer patterned as an array of circular disk nanoantennas, is investigated for resonantly enhancing Raman scattering from C-60 fullerene molecules deposited on the metamaterial. The metamaterial is designed to have resonant bands due to plasmonic and electromagnetic resonances at the Raman pump frequency (725 nm) as well as Stokes emission bands. The Raman scattering from C60 on the metamaterial with resonantly matched bands is measured to be enhanced by an order of magnitude more than from C60 on metamaterials with off-resonant absorption bands peaked at 1090 nm. The Raman pump is significantly enhanced due to the resonance with a propagating surface plasmon band, while the highly impedance matched electromagnetic resonance is expected to couple out the Raman emission efficiently. The nature and hybridization of the plasmonic and electromagnetic resonances to form compound resonances are investigated by...

  2. Highly tunable hybrid metamaterials employing split-ring resonators strongly coupled to graphene surface plasmons

    Science.gov (United States)

    Liu, Peter Q.; Luxmoore, Isaac J.; Mikhailov, Sergey A.; Savostianova, Nadja A.; Valmorra, Federico; Faist, Jérôme; Nash, Geoffrey R.

    2015-11-01

    Metamaterials and plasmonics are powerful tools for unconventional manipulation and harnessing of light. Metamaterials can be engineered to possess intriguing properties lacking in natural materials, such as negative refractive index. Plasmonics offers capabilities of confining light in subwavelength dimensions and enhancing light-matter interactions. Recently, the technological potential of graphene-based plasmonics has been recognized as the latter features large tunability, higher field-confinement and lower loss compared with metal-based plasmonics. Here, we introduce hybrid structures comprising graphene plasmonic resonators coupled to conventional split-ring resonators, thus demonstrating a type of highly tunable metamaterial, where the interaction between the two resonances reaches the strong-coupling regime. Such hybrid metamaterials are employed as high-speed THz modulators, exhibiting ~60% transmission modulation and operating speed in excess of 40 MHz. This device concept also provides a platform for exploring cavity-enhanced light-matter interactions and optical processes in graphene plasmonic structures for applications including sensing, photo-detection and nonlinear frequency generation.

  3. Highly tunable hybrid metamaterials employing split-ring resonators strongly coupled to graphene surface plasmons.

    Science.gov (United States)

    Liu, Peter Q; Luxmoore, Isaac J; Mikhailov, Sergey A; Savostianova, Nadja A; Valmorra, Federico; Faist, Jérôme; Nash, Geoffrey R

    2015-11-20

    Metamaterials and plasmonics are powerful tools for unconventional manipulation and harnessing of light. Metamaterials can be engineered to possess intriguing properties lacking in natural materials, such as negative refractive index. Plasmonics offers capabilities of confining light in subwavelength dimensions and enhancing light-matter interactions. Recently, the technological potential of graphene-based plasmonics has been recognized as the latter features large tunability, higher field-confinement and lower loss compared with metal-based plasmonics. Here, we introduce hybrid structures comprising graphene plasmonic resonators coupled to conventional split-ring resonators, thus demonstrating a type of highly tunable metamaterial, where the interaction between the two resonances reaches the strong-coupling regime. Such hybrid metamaterials are employed as high-speed THz modulators, exhibiting ∼60% transmission modulation and operating speed in excess of 40 MHz. This device concept also provides a platform for exploring cavity-enhanced light-matter interactions and optical processes in graphene plasmonic structures for applications including sensing, photo-detection and nonlinear frequency generation.

  4. Optical bistability effect in plasmonic racetrack resonator with high extinction ratio.

    Science.gov (United States)

    Wang, Xiaolei; Jiang, Houqiang; Chen, Junxue; Wang, Pei; Lu, Yonghua; Ming, Hai

    2011-09-26

    In this paper, optical bistability effect in an ultracompact plasmonic racetrack resonator with nonlinear optical Kerr medium is investigated both analytically and numerically. The properties of optical bistability and pump threshold are studied at 1.55 µm with various detuning parameters by an analytical model. The transmission switch from the upper branch to the lower branch with a pulse is also demonstrated by a finite-difference time-domain method. An extinction ratio of 97.8% and a switching time of 0.38 ps can be achieved with proper detuning parameter. Such a plasmonic resonator design provides a promising realization for highly effective optical modulators and switch.

  5. A single particle plasmon resonance study of 3D conical nanoantennas.

    Science.gov (United States)

    Schäfer, Christian; Gollmer, Dominik A; Horrer, Andreas; Fulmes, Julia; Weber-Bargioni, Alexander; Cabrini, Stefano; Schuck, P James; Kern, Dieter P; Fleischer, Monika

    2013-09-07

    Metallic nanocones are well-suited optical antennas for near-field microscopy and spectroscopy, exhibiting a number of different plasmonic modes. A major challenge in using nanocones for many applications is maximizing the signal at the tip while minimizing the background from the base. It is shown that nanocone plasmon resonance properties can be shifted over a wide range of wavelengths by variation of the substrate, material, size and shape, enabling potential control over specific modes and field distributions. The individual resonances are identified and studied by correlated single particle dark field scattering and scanning electron microscopy in combination with numerical simulations.

  6. Influence of sodium hydroxide in enhancing the surface plasmon resonance of silver nanoparticles

    Science.gov (United States)

    Yadav, Vijay D.; Jain, Ratnesh; Dandekar, Prajakta

    2017-08-01

    Herein, we report green synthesis of silver nanoparticles, by confluence graph described previously using acetate as the stabilizer as well as a reducing agent. The process involves use of ‘green’ chemicals and benign synthesis conditions. The synthesized nanoparticles were tuned for their surface plasmon resonance by sodium hydroxide addition and scanned between 400 to 800 nm to study the hyperchromic effect. As the concentration of sodium hydroxide increased, the surface plasmon resonance of the silver nanoparticles at 420 nm increased (hyperchromic effect). The synthesized silver nanoparticles were further characterized by TEM, for morphology analysis and laser scattering for the electromagnetic properties of nanoparticles. Our method may provide a gateway for intensive exploration of innovative approaches in synthesizing silver nanoparticles and tuning (hyperchromic effect) their localized surface plasmon resonance by using sodium hydroxide, which has tremendous utility in diverse application sectors.

  7. Design of Highly Sensitive Surface Plasmon Resonance Sensors Using Planar Metallic Films Closely Coupled to Nanogratings

    Institute of Scientific and Technical Information of China (English)

    YANG Xiao-Yan; XIE Wen-Chong; LIU De-Ming

    2008-01-01

    We investigate the sensitivity enhancement of surface plasmon resonance(SPR)sensors using planar metallic films closely coupled to nanogratings.The strong coupling between localized surface plasmon resonances(LSPRs)presenting in metallic nanostructures and surface plasmon polaritons(SPPs)propagating at the metallic film surface leads to changes of resonance reflection properties,resulting in enhanced sensitivity of SPR sensors.The effects of thickness of the metallic films,grating period and metal materials on the refractive index sensitivity of the device are investigated.The refractive index sensitivity of nanograting-based SPR sensors is predicted to be about 543 nm/RIU(refractive index unit)using optimized structure parameters.Our study on SPR sensors using planar metallic films closely coupled to nanogratings demonstrates the potential for significant improvement in refractive index sensitivity.

  8. A BIOSENSOR USING COUPLED PLASMON WAVEGUIDE RESONANCE COMBINED WITH HYPERSPECTRAL FLUORESCENCE ANALYSIS

    Directory of Open Access Journals (Sweden)

    CHAN DU

    2014-01-01

    Full Text Available We developed a biosensor that is capable for simultaneous surface plasmon resonance (SPR sensing and hyperspectral fluorescence analysis in this paper. A symmetrical metal-dielectric slab scheme is employed for the excitation of coupled plasmon waveguide resonance (CPWR in the present work. Resonance between surface plasmon mode and the guided waveguide mode generates narrower full width half-maximum of the reflective curves which leads to increased precision for the determination of refractive index over conventional SPR sensors. In addition, CPWR also offers longer surface propagation depths and higher surface electric field strengths that enable the excitation of fluorescence with hyperspectral technique to maintain an appreciable signal-to-noise ratio. The refractive index information obtained from SPR sensing and the chemical properties obtained through hyperspectral fluorescence analysis confirm each other to exclude false-positive or false-negative cases. The sensor provides a comprehensive understanding of the biological events on the sensor chips.

  9. Toward an Enhancement of the Photoactivity of Multiphotochromic Dimers Using Plasmon Resonance: A Theoretical Study.

    Science.gov (United States)

    Fihey, Arnaud; Le Guennic, Boris; Jacquemin, Denis

    2015-08-06

    Building dimers of organic photochromic compounds paves the way to multifunctional switches, but such architectures often undergo partial photoreactivity only. Combining photochromism of molecules and plasmon resonance of gold nanoparticles (NPs) is known to affect the photochromism of monomers, yet the impact on multimers remains unknown. Here we propose a theoretical study of dimers of dithienylethenes by the mean of a hybrid calculation scheme (discrete-interaction model/quantum mechanics). We aim to assess how the optical properties of multiphotochromes are tuned by the influence of the plasmon resonances. We show that, for a typical chemisorption orientation on the NP, the absorption bands responsible for the photochromism are significantly enhanced for both the doubly open and mixed closed-open isomers of the dyad, hinting that plasmon resonance could be used to boost the generally poor photoactivity of dithienylethene dyads.

  10. Quantum electrodynamics and plasmonic resonance of metallic nanostructures

    Science.gov (United States)

    Zhang, Mingliang; Xiang, Hongping; Zhang, Xu; Lu, Gang

    2016-04-01

    Plasmonic resonance of a metallic nanostructure results from coherent motion of its conduction electrons driven by incident light. At the resonance, the induced dipole in the nanostructure is proportional to the number of the conduction electrons, hence 107 times larger than that in an atom. The interaction energy between the induced dipole and fluctuating virtual field of the incident light can reach a few tenths of an eV. Therefore, the classical electromagnetism dominating the field may become inadequate. We propose that quantum electrodynamics (QED) may be used as a fundamental theory to describe the interaction between the virtual field and the oscillating electrons. Based on QED, we derive analytic expressions for the plasmon resonant frequency, which depends on three easily accessible material parameters. The analytic theory reproduces very well the experimental data, and can be used in rational design of materials for plasmonic applications.

  11. Quantum electrodynamics and plasmonic resonance of metallic nanostructures.

    Science.gov (United States)

    Zhang, Mingliang; Xiang, Hongping; Zhang, Xu; Lu, Gang

    2016-04-20

    Plasmonic resonance of a metallic nanostructure results from coherent motion of its conduction electrons driven by incident light. At the resonance, the induced dipole in the nanostructure is proportional to the number of the conduction electrons, hence 10(7) times larger than that in an atom. The interaction energy between the induced dipole and fluctuating virtual field of the incident light can reach a few tenths of an eV. Therefore, the classical electromagnetism dominating the field may become inadequate. We propose that quantum electrodynamics (QED) may be used as a fundamental theory to describe the interaction between the virtual field and the oscillating electrons. Based on QED, we derive analytic expressions for the plasmon resonant frequency, which depends on three easily accessible material parameters. The analytic theory reproduces very well the experimental data, and can be used in rational design of materials for plasmonic applications.

  12. Resonant Excitation of Terahertz Surface Plasmons in Subwavelength Metal Holes

    Directory of Open Access Journals (Sweden)

    Weili Zhang

    2007-01-01

    Full Text Available We present a review of experimental studies of resonant excitation of terahertz surface plasmons in two-dimensional arrays of subwavelength metal holes. Resonant transmission efficiency higher than unity was recently achieved when normalized to the area occupied by the holes. The effects of hole shape, hole dimensions, dielectric function of metals, polarization dependence, and array film thickness on resonant terahertz transmission in metal arrays were investigated by the state-of-the-art terahertz time-domain spectroscopy. In particular, extraordinary terahertz transmission was demonstrated in arrays of subwavelength holes made even from Pb, a generally poor metal, and having thickness of only one-third of skin depth. Terahertz surface plasmons have potential applications in terahertz imaging, biosensing, interconnects, and development of integrated plasmonic components for terahertz generation and detection.

  13. Resonant plasmonic nanoparticles for multicolor second harmonic imaging

    Science.gov (United States)

    Accanto, Nicolò; Piatkowski, Lukasz; Hancu, Ion M.; Renger, Jan; van Hulst, Niek F.

    2016-02-01

    Nanoparticles capable of efficiently generating nonlinear optical signals, like second harmonic generation, are attracting a lot of attention as potential background-free and stable nano-probes for biological imaging. However, second harmonic nanoparticles of different species do not produce readily distinguishable optical signals, as the excitation laser mainly defines their second harmonic spectrum. This is in marked contrast to other fluorescent nano-probes like quantum dots that emit light at different colors depending on their sizes and materials. Here, we present the use of resonant plasmonic nanoparticles, combined with broadband phase-controlled laser pulses, as tunable sources of multicolor second harmonic generation. The resonant plasmonic nanoparticles strongly interact with the electromagnetic field of the incident light, enhancing the efficiency of nonlinear optical processes. Because the plasmon resonance in these structures is spectrally narrower than the laser bandwidth, the plasmonic nanoparticles imprint their fingerprints on the second harmonic spectrum. We show how nanoparticles of different sizes produce different colors in the second harmonic spectra even when excited with the same laser pulse. Using these resonant plasmonic nanoparticles as nano-probes is promising for multicolor second harmonic imaging while keeping all the advantages of nonlinear optical microscopy.

  14. Plasmonic resonances in nanostructured transparent conducting oxide films

    CERN Document Server

    Kim, Jongbum; Emani, Naresh K; Boltasseva, Alexandra

    2012-01-01

    Transparent conducting oxides (TCO) are emerging as possible alternative constituent materials to replace noble metals such as silver and gold for low-loss plasmonic and metamaterial (MMs) applications in the near infrared (NIR) regime. The optical characteristics of TCOs have been studied to evaluate the functionalities and potential of these materials as metal substitutes in plasmonic and MM devices, even apart from their usual use as electrode materials. However, patterning TCOs at the nanoscale, which is necessary for plasmonic and MM devices, is not well-studied. This paper investigates nanopatterning processes for TCOs, especially the lift-off technique with electron-beam lithography, and the realization of plasmonic nanostructures with TCOs. By employing the developed nanopatterning process, we fabricate 2D-periodic arrays of TCO nanodisks and characterize the material's plasmonic properties to evaluate the performance of TCOs as metal substitutes. Light-induced collective oscillations of the free elec...

  15. Influence of stabilizing agent and synthesis temperature on the optical properties of silver nanoparticles as active materials in surface plasmon resonance (SPR) biosensor

    Science.gov (United States)

    Mahmudin, Lufsyi; Suharyadi, Edi; Utomo, Agung Bambang Setio; Abraha, Kamsul

    2016-04-01

    It has been successfully carried out the synthesis of colloidal silver nanoparticles by chemical reduction method. Silver nitrate (AgNO3) was used as metal precursors and trisodium citrate as the reducing agent. In the synthesis process, were varied the stabilizing agent of Polyvinyl Alcohol (PVA) and polyvinylpyrrolidone (PVP) and heating temperature. The formation of silver nanoparticles was observed visually with discoloration (yellowish). The formation and the structure of silver nanoparticles in colloidal solution were further examined through their optical properties by using a UV-Vis spectrometer. The wavelength absorption spectrum of colloidal silver nanoparticles shows that maximum surface plasmon absorption for the trisodium citrate-synthesized nanoparticles was at 429.43 nm for temperature of 90°C. The addition of the stabilizer sharpened spectrum curves and caused red shift in the maximum absorption peak of 429.01 nm and 427.09 nm for PVA and PVP respectively. Meanwhile, the addition of the synthesis temperature also sharpened the maximum surface plasmon absorption band and the red shift the maximum absorption peak of 428.79 nm and 428.58 nm for temperature of 110°C and 120°C respectively. Red shift of the maximum absorption peak indicates a smaller particle size. The maximum surface plasmon absorption band in the range of 427.09 nm to 429.43 nm indicates the presence of spherical or roughly spherical silver nanoparticles and TEM imaging confirmed this shape. TEM imaging results show that the diameter size of the silver nanoparticles range of 10 nm to 60 nm as well as the morphology (crystallites) of silver nanoparticles have spherical geometry with particle distribution which quite dispersive. The dispersibility of nanoparticles such as this could potentially be used as an active material of SPR biosensor.

  16. Collective electric and magnetic plasmonic resonances in spherical nanoclusters.

    Science.gov (United States)

    Vallecchi, Andrea; Albani, Matteo; Capolino, Filippo

    2011-01-31

    We report an investigation on the optical properties of three-dimensional nanoclusters (NCs) made by spherical constellations of metallic nanospheres arranged around a central dielectric sphere, which can be realized and assembled by current state-of-the-art nanochemistry techniques. This type of NCs supports collective plasmon modes among which the most relevant are those associated with the induced electric and magnetic resonances. Combining a single dipole approximation for each nanoparticle and the multipole spherical-wave expansion of the scattered field, we achieve an effective characterization of the optical response of individual NCs in terms of their scattering, absorption, and extinction efficiencies. By this approximate model we analyze a few sample NCs identifying the electric and magnetic resonance frequencies and their dependence on the size and number of the constituent nanoparticles. Furthermore, we discuss the effective electric and magnetic polarizabilities of the NCs, and their isotropic properties. A homogenization method based on an extension of the Maxwell Garnett model to account for interaction effects due to higher order multipoles in dense packed arrays is applied to a distribution of NCs showing the possibility of obtaining metamaterials with very large, small, and negative values of permittivity and permeability, and even negative index.

  17. The role of the plasmon resonance for enhanced optical forces

    Science.gov (United States)

    Ploschner, Martin

    Optical manipulation of nanoscale objects is studied with particular emphasis on the role of plasmon resonance for enhancement of optical forces. The thesis provides an introduction to plasmon resonance and its role in confinement of light to a sub-diffraction volume. The strong light confinement and related enhancement of optical forces is then theoretically studied for a special case of nanoantenna supporting plasmon resonances. The calculation of optical forces, based on the Maxwell stress tensor approach, reveals relatively weak optical forces for incident powers that are used in typical realisations of trapping with nanoantenna. The optical forces are so weak that other non-optical effects should be considered to explain the observed trapping. These effects include heating induced convection, thermoporesis and chemical binding. The thesis also studies the optical effects of plasmon resonances for a fundamentally different application - size-based optical sorting of gold nanoparticles. Here, the plasmon resonances are not utilised for sub-diffraction light confinement but rather for their ability to increase the apparent cross-section of the particles for their respective resonant sizes. Exploiting these resonances, we realise sorting in a system of two counter-propagating evanescent waves, each at different wavelength that selectively guide gold nanoparticles of different sizes in opposite directions. The method is experimentally demonstrated for bidirectional sorting of gold nanoparticles of either 150 or 130 nm in diameter from those of 100 nm in diameter within a mixture. We conclude the thesis with a numerical study of the optimal beam-shape for optical sorting applications. The developed theoretical framework, based on the force optical eigenmode method, is able to find an illumination of the back-focal plane of the objective such that the force difference between nanoparticles of various sizes in the sample plane is maximised.

  18. Fano-like interference of plasmon resonances at a single rod-shaped nanoantenna

    CERN Document Server

    López-Tejeira, F; Rodríguez-Oliveros, R; Sánchez-Gil, J A

    2011-01-01

    Single metallic nanorods acting as half-wave antennas in the optical range exhibit an asymmetric, multi-resonant scattering spectrum that strongly depends on both their length and dielectric properties. Here we show that such spectral features can be easily understood in terms of Fano-like interference between adjacent plasmon resonances. On the basis of analytical and numerical results for different geometries, we demonstrate that Fano resonances may appear for such single-particle nanoantennas provided that interacting resonances overlap in both spatial and frequency domains.

  19. Plasmon coupling in vertical split-ring resonator metamolecules

    Science.gov (United States)

    Wu, Pin Chieh; Hsu, Wei-Lun; Chen, Wei Ting; Huang, Yao-Wei; Liao, Chun Yen; Liu, Ai Qun; Zheludev, Nikolay I.; Sun, Greg; Tsai, Din Ping

    2015-01-01

    The past decade has seen a number of interesting designs proposed and implemented to generate artificial magnetism at optical frequencies using plasmonic metamaterials, but owing to the planar configurations of typically fabricated metamolecules that make up the metamaterials, the magnetic response is mainly driven by the electric field of the incident electromagnetic wave. We recently fabricated vertical split-ring resonators (VSRRs) which behave as magnetic metamolecules sensitive to both incident electric and magnetic fields with stronger induced magnetic dipole moment upon excitation in comparison to planar SRRs. The fabrication technique enabled us to study the plasmon coupling between VSRRs that stand up side by side where the coupling strength can be precisely controlled by varying the gap in between. The resulting wide tuning range of these resonance modes offers the possibility of developing frequency selective functional devices such as sensors and filters based on plasmon coupling with high sensitivity. PMID:26043931

  20. Geometry dependence of surface lattice resonances in plasmonic nanoparticle arrays

    CERN Document Server

    Guo, R; Törmä, P

    2016-01-01

    Plasmonic nanoarrays which support collective surface lattice resonances (SLRs) have become an exciting frontier in plasmonics. Compared with the localized surface plasmon resonance (LSPR) in individual particles, these collective modes have appealing advantages such as angle-dependent dispersions and much narrower linewidths. Here, we investigate systematically how the geometry of the lattice affects the SLRs supported by metallic nanoparticles. We present a general theoretical framework from which the various SLR modes of a given geometry can be straightforwardly obtained by a simple comparison of the diffractive order (DO) vectors and orientation of the nanoparticle dipole given by the polarization of the incident field. Our experimental measurements show that while square, hexagonal, rectangular, honeycomb and Lieb lattice arrays have similar spectra near the $\\Gamma$-point ($k=0$), they have remarkably different SLR dispersions. Furthermore, their dispersions are highly dependent on the polarization. Num...

  1. Effective Optical Properties of Plasmonic Nanocomposites

    Directory of Open Access Journals (Sweden)

    Christoph Etrich

    2014-01-01

    Full Text Available Plasmonic nanocomposites find many applications, such as nanometric coatings in emerging fields, such as optotronics, photovoltaics or integrated optics. To make use of their ability to affect light propagation in an unprecedented manner, plasmonic nanocomposites should consist of densely packed metallic nanoparticles. This causes a major challenge for their theoretical description, since the reliable assignment of effective optical properties with established effective medium theories is no longer possible. Established theories, e.g., the Maxwell-Garnett formalism, are only applicable for strongly diluted nanocomposites. This effective description, however, is a prerequisite to consider plasmonic nanocomposites in the design of optical devices. Here, we mitigate this problem and use full wave optical simulations to assign effective properties to plasmonic nanocomposites with filling fractions close to the percolation threshold. We show that these effective properties can be used to properly predict the optical action of functional devices that contain nanocomposites in their design. With this contribution we pave the way to consider plasmonic nanocomposites comparably to ordinary materials in the design of optical elements.

  2. Tuneable and robust long range surface plasmon resonance for biosensing applications

    Science.gov (United States)

    Méjard, Régis; Dostálek, Jakub; Huang, Chun-Jen; Griesser, Hans; Thierry, Benjamin

    2013-10-01

    A multilayered biosensing architecture based on long range surface plasmons (LRSPs) is reported. LRSPs originate from the coupling of surface plasmons on the opposite sides of a thin metal film embedded in a symmetrical refractive index environment. With respect to regular SPs, LRSPs are characterized by extended electromagnetic field profiles and lower losses, making them of high interest in biosensing, especially for large biological entities. LRSPs-supporting layer structures are typically prepared by using fluoropolymers with refractive indices close to that of water. Unfortunately, fluoropolymers have low surface energies which can translate into poor adhesion to substrates and sub-optimal properties of coatings with surface plasmon resonance-active metal layers such as gold. In this work, a multilayered fluoropolymer structure with tuneable average refractive index is described and used to adjust the penetration depth of LRSP from the sensor surface. The proposed methodology also provides a simple solution to increase the adhesion of LRSP-supporting structures to glass substrates. Towards taking full advantage of long range surface plasmon resonance sensors, a novel approach based on the plasma-polymerization of allylamine is also described to improve the quality of gold layers on fluoropolymers such as Teflon AF. Through these advancements, long range surface plasmon resonance sensors were fabricated with figures of merit as high as 466 RIU-1. The remarkable performance of these sensors combined with their high stability is expected to foster applications of LRSPR in biosensing.

  3. Analysis of cell surface antigens by Surface Plasmon Resonance imaging

    NARCIS (Netherlands)

    Stojanovic, I.; Schasfoort, R.B.M.; Terstappen, L.W.M.M.

    2013-01-01

    Surface Plasmon Resonance (SPR) is most commonly used to measure bio-molecular interactions. SPR is used significantly less frequent for measuring whole cell interactions. Here we introduce a method to measure whole cells label free using the specific binding of cell surface antigens expressed on th

  4. Optimization of Pd Surface Plasmon Resonance sensors for hydrogen detection

    NARCIS (Netherlands)

    Perrotton, C.; Javahiraly, N.; Slaman, M.; Schreuders, H.; Dam, B.; Meyrueis, P.

    2011-01-01

    A design to optimize a fiber optic Surface Plasmon Resonance (SPR) sensor using Palladium as a sensitive layer for hydrogen detection is presented. In this approach, the sensitive layer is deposited on the core of a multimode fiber, after removing the optical cladding. The light is injected in the f

  5. Single cell targeting using plasmon resonant gold-coated liposomes

    Science.gov (United States)

    Leung, Sarah J.; Romanowski, Marek

    2012-03-01

    We have developed an experimental system with the potential for the delivery and localized release of an encapsulated agent with high spatial and temporal resolution. We previously introduced liposome-supported plasmon resonant gold nanoshells; in this composite structure, the liposome allows for the encapsulation of substances, such as therapeutic agents, neurotransmitters, or growth factors, and the plasmon resonant structure facilitates the rapid release of encapsulated contents upon laser light illumination. More recently, we demonstrated that these gold-coated liposomes are capable of releasing their contents in a spectrally-controlled manner, where plasmon resonant nanoparticles only release content upon illumination with a wavelength of light matching their plasmon resonance band. We now show that this release mechanism can be used in a biological setting to deliver a peptide derivative of cholecystokinin to HEK293 cells overexpressing the CCK2 receptor. Using directed laser light, we may enable localized release from gold-coated liposomes to enable accurate perturbation of cellular functions in response to released compounds; this system may have possible applications in signaling pathways and drug discovery.

  6. Analysis of cell surface antigens by Surface Plasmon Resonance imaging

    NARCIS (Netherlands)

    Stojanovic, Ivan; Schasfoort, Richardus B.M.; Terstappen, Leonardus Wendelinus Mathias Marie

    2013-01-01

    Surface Plasmon Resonance (SPR) is most commonly used to measure bio-molecular interactions. SPR is used significantly less frequent for measuring whole cell interactions. Here we introduce a method to measure whole cells label free using the specific binding of cell surface antigens expressed on th

  7. A Surface Plasmon Resonance Immunobiosensor for Detection of Phytophthora infestans

    DEFF Research Database (Denmark)

    Skottrup, Peter; Frøkiær, Hanne; Hejgaard, Jørn;

    In this study we focused on the development of a Surface Plasmon Resonance (SPR) immunosensor for Phytophthora infestans detection. The fungus-like organism is the cause of potato late blight and is a major problem in potato growing regions of the world. Efficient control is dependent on early...

  8. Surface Plasmon Resonance Spectroscopy: A Versatile Technique in a

    Science.gov (United States)

    Bakhtiar, Ray

    2013-01-01

    Surface plasmon resonance (SPR) spectroscopy is a powerful, label-free technique to monitor noncovalent molecular interactions in real time and in a noninvasive fashion. As a label-free assay, SPR does not require tags, dyes, or specialized reagents (e.g., enzymes-substrate complexes) to elicit a visible or a fluorescence signal. During the last…

  9. Optimization of Pd Surface Plasmon Resonance sensors for hydrogen detection

    NARCIS (Netherlands)

    Perrotton, C.; Javahiraly, N.; Slaman, M.; Schreuders, H.; Dam, B.; Meyrueis, P.

    2011-01-01

    A design to optimize a fiber optic Surface Plasmon Resonance (SPR) sensor using Palladium as a sensitive layer for hydrogen detection is presented. In this approach, the sensitive layer is deposited on the core of a multimode fiber, after removing the optical cladding. The light is injected in the f

  10. Highly Stable Silver Nanoplates for Surface Plasmon Resonance Biosensing

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Chuanbo [University of California, Riverside; Lu, Zhenda [University of California, Riverside; Chi, Miaofang [ORNL; Liu, ying [University of California, Riverside; Cheng, Quan [University of California, Riverside; Yin, Yadong [University of California, Riverside

    2012-01-01

    An SPR biosensor was developed by employing highly stable Au-protected Ag nanoplates (NP) as enhancers (see picture). Superior performance was achieved by depositing a thin and uniform coating of Au on the Ag surface while minimizing disruptive galvanic replacement and retaining the strong surface plasmon resonance (SPR) of the silver nanoplates.

  11. Passive Infrared Sensing Using Plasmonic Resonant Dust Particles

    Directory of Open Access Journals (Sweden)

    Mark Mirotznik

    2012-01-01

    Full Text Available We present computational and experimental results of dust particles that can be tuned to preferentially reflect or emit IR radiation within the 8–14 μm band. The particles consist of thin metallic subwavelength gratings patterned on the surface of a simple quarter wavelength cavity. This design creates distinct IR absorption resonances by combining the plasmonic resonance of the grating with the natural resonance of the cavity. We show that the resonance peaks are easily tuned by varying either the geometry of the grating or the thickness of the cavity. Here, we present a computational design algorithm along with experimental results that validate the design methodology.

  12. Plasmon properties and hybridization effects in silicene

    Science.gov (United States)

    Vacacela Gomez, C.; Pisarra, M.; Gravina, M.; Riccardi, P.; Sindona, A.

    2017-02-01

    The plasmonic character of monolayer silicene is investigated by time-dependent density functional theory in the random phase approximation. Both the intrinsic (undoped) and several extrinsic (carrier doped or gated) conditions are explored by simulating injection of a probe particle (i.e., an electron or a photon) of energy below 20 eV and in-plane momentum smaller than 1.1 Å -1 . The energy-loss function of the system is analyzed, with particular reference to its induced charge-density fluctuations, i.e., plasmon resonances and corresponding dispersions, occurring in the investigated energy-momentum region. At energies larger than 1.5 eV, two intrinsic interband modes are detected and characterized. The first one is a hybridized π -like plasmon, which is assisted by competing one-electron processes involving s p2 and s p3 states, and depends on the slightest changes in specific geometric parameters, such as nearest-neighbor atomic distance and buckling constant. The second one is a more conventional π -σ plasmon, which is more intense than the π -like plasmon and more affected by one-electron processes involving the σ bands with respect to the analogous collective oscillation in monolayer graphene. At energies below 1 eV, two extrinsic intraband modes are predicted to occur, which are generated by distinct types of Dirac electrons (associated with different Fermi velocities at the so-called Dirac points). The most intense of them is a two-dimensional plasmon, having an energy-momentum dispersion that resembles that of a two-dimensional electron gas. The other is an acoustic plasmon that occurs for specific momentum directions and competes with the two-dimensional plasmon at mid-infrared energies. The strong anisotropic character of this mode cannot be explained in terms of the widely used Dirac-cone approximation. As in mono-, bi-, and few-layer graphene, the extrinsic oscillations of silicene are highly sensitive to the concentration of injected or ejected

  13. Counterintuitive dispersion effect near surface plasmon resonances in Otto structures

    Science.gov (United States)

    Wang, Lin; Wang, Li-Gang; Ye, Lin-Hua; Al-Amri, M.; Zhu, Shi-Yao; Zubairy, M. Suhail

    2016-07-01

    In this paper, we investigate the counterintuitive dispersion effect associated with the poles and zeros of reflection and transmission functions in an Otto configuration when a surface plasmon resonance is excited. We show that the zeros and/or poles in the reflection and transmission functions may move into the upper-half complex-frequency plane (CFP), and these locations of the zeros and poles determine the dispersion properties of the whole structures (i.e., the frequency-dependent change of both reflected and transmitted phases). Meanwhile, we demonstrate various dispersion effects (both normal and abnormal) related to the changes of the poles and zeros in both reflection and transmission functions when considering the properties of metal substrates. For a realistic metal substrate in an Otto structure, there are the optimal thickness and incident angle, which correspond to the transitions of the zeros in the reflection function from the upper-half to lower-half CFP. These properties may be helpful to manipulate light propagation in optical devices.

  14. Plasmonic resonant solitons in metallic nanosuspensions.

    Science.gov (United States)

    Fardad, Shima; Salandrino, Alessandro; Heinrich, Matthias; Zhang, Peng; Chen, Zhigang; Christodoulides, Demetrios N

    2014-05-14

    Robust propagation of self-trapped light over distances exceeding 25 diffraction lengths has been demonstrated for the first time in plasmonic nanosuspensions. This phenomenon results from the interplay between optical forces and enhanced polarizability that would have been otherwise impossible in conventional dielectric dispersions. Plasmonic nanostructures such as core-shell particles, nanorods, and spheres are shown to display tunable polarizabilities depending on their size, shape, and composition, as well as the wavelength of illumination. Here we discuss nonlinear light-matter dynamics arising from an effective positive Kerr effect, which in turn allows for deep penetration of long needles of light through dissipative colloidal media. Our findings may open up new possibilities toward synthesizing soft-matter systems with customized optical nonlinearities.

  15. Angle-Resolved Plasmonic Properties of Single Gold Nanorod Dimers

    Institute of Scientific and Technical Information of China (English)

    Jian Wu; Xuxing Lu; Qiannan Zhu; Junwei Zhao; Qishun Shen; Li Zhan; Weihai Ni

    2014-01-01

    Through wet-chemical assembly methods, gold nanorods were placed close to each other and formed a dimer with a gap distance*1 nm, and hence degenerated plasmonic dipole modes of individual nanorods coupled together to produce hybridized bonding and antibonding resonance modes. Previous studies using a condenser for illumination result in averaged signals over all excitation angles. By exciting an individual dimer obliquely at different angles, we demonstrate that these two new resonance modes are highly tunable and sensitive to the angle between the excitation polarization and the dimer orientation, which follows cos2u dependence. Moreover, for dimer structures with various structure angles, the resonance wavelengths as well as the refractive index sensitivities were found independent of the structure angle. Cal-culated angle-resolved plasmonic properties are in good agreement with the measurements. The assembled nanostructures investigated here are important for fundamental researches as well as potential applications when they are used as building blocks in plasmon-based optical and optoelectronic devices.

  16. Enhanced Sensitivity of Surface Plasmon Resonance Sensor Based on Bilayers of Silver-Barium Titanate

    Directory of Open Access Journals (Sweden)

    S. Fouad

    2016-12-01

    Full Text Available Surface plasmon resonance (SPR sensors have been widely adopted with various fields such as physics, chemistry, biology and biochemistry. SPR sensor has many advantages like the less number of sensing samples required, freedom of electromagnetic interference and higher sensitivity. This research investigates the phase interrogation technique of a surface plasmon resonance sensor based on silver and thin film dielectric material of Barium titanate layers. Barium titanate (BaTiO3 layer is adopted due to its excellent dielectric properties such as high dielectric constant and low dielectric loss. The numerical results demonstrate that the fusion of the proposed material BaTiO3 layer into surface plasmon resonance sensor yields a higher sensitivity of 280 degree/RIU in comparison with surface plasmon resonance sensor without BaTiO3 layer which shows only a sensitivity of 120 degree/RIU. As the thickness of this layer increases from 5 nm to 10 nm, the sensitivity is enhanced from 160 degree/RIU to 280 degree/RIU for a fixed metal layer of silver with a thickness of (70 nm.

  17. Microfluidic transmission surface plasmon resonance enhancement for biosensor applications

    Science.gov (United States)

    Lertvachirapaiboon, Chutiparn; Baba, Akira; Ekgasit, Sanong; Shinbo, Kazunari; Kato, Keizo; Kaneko, Futao

    2017-01-01

    The microfluidic transmission surface plasmon resonance (MTSPR) constructed by assembling a gold-coated grating substrate with a microchannel was employed for biosensor application. The transmission surface plasmon resonance spectrum obtained from the MTSPR sensor chip showed a strong and narrow surface plasmon resonance (SPR) peak located between 650 and 800 nm. The maximum SPR excitation was observed at an incident angle of 35°. The MTSPR sensor chip was employed for glucose sensor application. Gold-coated grating substrates were functionalized using 3-mercapto-1-propanesulfonic acid sodium salt and subsequently functionalized using a five-bilayer poly(allylamine hydrochloride)/poly(sodium 4-styrenesulfonate) to facilitate the coupling/decoupling of the surface plasmon and to prepare a uniform surface for sensing. The detection limit of our developed system for glucose was 2.31 mM. This practical platform represents a high possibility of further developing several biomolecules, multiplex systems, and a point-of-care assay for practical biosensor applications.

  18. Gap plasmon resonator arrays for unidirectional launching and shaping of surface plasmon polaritons

    CERN Document Server

    Lei, Zeyu

    2015-01-01

    We report the design and experimental realization of a kind of miniaturized devices for efficient unidirectional launching and shaping of surface plasmon polaritons (SPPs). Each device consists of an array of evenly spaced gap plasmon resonators with varying dimensions. Particle swarm optimization is used to achieve a theoretical two dimensional launching efficiency of about 51%, under the normal illumination of a 5-{\\mu}m waist Gaussian beam at 780 nm. By modifying the wavefront of the SPPs, unidirectional SPPs with focused, Bessel and Airy profiles are launched and imaged with leakage radiation microscopy.

  19. Mid-infrared plasmonic resonances exploiting heavily-doped Ge on Si

    Science.gov (United States)

    Biagioni, P.; Sakat, E.; Baldassarre, L.; Calandrini, E.; Samarelli, A.; Gallacher, K.; Frigerio, J.; Isella, G.; Paul, D. J.; Ortolani, M.

    2015-03-01

    We address the behavior of mid-infrared localized plasmon resonances in elongated germanium antennas integrated on silicon substrates. Calculations based on Mie theory and on the experimentally retrieved dielectric constant allow us to study the tunability and the figures of merit of plasmon resonances in heavily-doped germanium and to preliminarily compare them with those of the most established plasmonic material, gold.

  20. Localized spoof surface plasmon resonances at terahertz range

    Science.gov (United States)

    Chen, Lin; Xu, Mengjian; Zang, Xiaofei; Peng, Yan; Zhu, Yiming

    2016-11-01

    The influence of the inner disk radius r, the filling ratio α, numbers of sectors N, and the gap g on transmission response for corrugated metallic disk (CMD) with single C-shaped resonator(CSR) has been fully studied. The results indicate that varying parameters r can efficiently excite the higher order spoof localized surface plasmon modes in corrugated metallic disk. The relationship between the bright dipole and dark multipolar resonances presents the possibility of high Q dark resonances excitation. All results may be of great interest for diverse applications.

  1. Graphene: A Dynamic Platform for Electrical Control of Plasmonic Resonance

    DEFF Research Database (Denmark)

    Emani, Naresh Kumar; Kildishev, Alexander V.; Shalaev, Vladimir M.

    2015-01-01

    Graphene has recently emerged as a viable platform for integrated optoelectronic and hybrid photonic devices because of its unique properties. The optical properties of graphene can be dynamically controlled by electrical voltage and have been used to modulate the plasmons in noble metal nanostru...

  2. EIT-like transmission by interaction between multiple Bragg scattering and local plasmonic resonances

    CERN Document Server

    Liu, Z Z; Xiao, J J

    2015-01-01

    We study the optical properties associated to both the polariton gap and the Bragg gap in periodic resonator-waveguide coupled system, based on the temporal coupled mode theory and the transfer matrix method. By the complex band and the transmission spectrum, it is feasible to tune the interaction between multiple Bragg scattering and the local resonance, which may give rise to analogous phenomena of electromagnetically induced transparency (EIT). We further design a plasmonic slot waveguide side-coupled with local plasmonic resonator to demonstrate the EIT-like effects in the near-infared band. Numerical calculations show that realistic amount of metal Joule loss may destroy the interference and the total absorption is enhanced in the transparency windwo due to the near zero group velocity of the guiding wave.

  3. Flexible, fibre-addressable surface-plasmon-resonance chip

    Science.gov (United States)

    Chowdhury, Faqrul; Chau, Kenneth J.

    2012-02-01

    Surface plasmon resonance (SPR) sensors exploit optical coupling to surface plasmons, light waves bound to a metal surface. In the most common configuration, a SPR sensor is used with an external light source, optical components to polarize incident light and guide light to and from a metal surface, a coupling device to convert free-space light into surface plasmons and back into free-space light, and a light detector. The light source, the optical components, and the light detector are external to the SPR device, and the coupling structure is often integrated directly with the surface-plasmon-sustaining metal surface. The requirement of several external components restricts the miniaturization of SPR devices and prohibits low-cost implementation. To address these limitations, we design, fabricate, and test a new SPR device chip that is fibre-addressable, does not require a discrete coupling structure, and integrates light delivery, light polarization control, surface plasmon coupling onto a thin, flexible substrate. Our SPR chip is constructed from a thin gold layer deposited on top of a clear plastic sheet, which is then optically connected from the bottom surface onto a plastic linear polarizer sheet. Two cleaved fibres, one to input light and the other to collect reflected light, are then optically attached to SPR device. We experimentally characterize the SPR device and find good agreement between our measurements and a theoretical model based on transfer matrix formalism.

  4. Resonance coupling in plasmonic nanomatryoshka homo- and heterodimers

    Science.gov (United States)

    Ahmadivand, Arash; Sinha, Raju; Pala, Nezih

    2016-06-01

    Here, we examine the electromagnetic (EM) energy coupling and hybridization of plasmon resonances between closely spaced concentric nanoshells known as "nanomatryoshka" (NM) units in symmetric and antisymmetric compositions using the Finite Difference Time Domain (FDTD) analysis. Utilizing plasmon hybridization model, we calculated the energy level diagrams and verified that, in the symmetric dimer (in-phase mode in a homodimer), plasmonic bonding modes are dominant and tunable within the considered bandwidth. In contrast, in the antisymmetric dimer (out-of-phase mode in a heterodimer), due to the lack of the geometrical symmetry, new antibonding modes appear in the extinction profile, and this condition gives rise to repeal of dipolar field coupling. We also studied the extinction spectra and positions of the antibonding and bonding modes excited due to the energy coupling between silver and gold NM units in a heterodimer structure. Our analysis suggest abnormal shifts in the higher energy modes. We propose a method to analyze the behavior of multilayer concentric nanoshell particles in an antisymmetric orientation employing full dielectric function calculations and the Drude model based on interband transitions in metallic components. This study provides a method to predict the behavior of the higher energy plasmon resonant modes in entirely antisymmetric structures such as compositional heterodimers.

  5. Resonance coupling in plasmonic nanomatryoshka homo- and heterodimers

    Directory of Open Access Journals (Sweden)

    Arash Ahmadivand

    2016-06-01

    Full Text Available Here, we examine the electromagnetic (EM energy coupling and hybridization of plasmon resonances between closely spaced concentric nanoshells known as “nanomatryoshka” (NM units in symmetric and antisymmetric compositions using the Finite Difference Time Domain (FDTD analysis. Utilizing plasmon hybridization model, we calculated the energy level diagrams and verified that, in the symmetric dimer (in-phase mode in a homodimer, plasmonic bonding modes are dominant and tunable within the considered bandwidth. In contrast, in the antisymmetric dimer (out-of-phase mode in a heterodimer, due to the lack of the geometrical symmetry, new antibonding modes appear in the extinction profile, and this condition gives rise to repeal of dipolar field coupling. We also studied the extinction spectra and positions of the antibonding and bonding modes excited due to the energy coupling between silver and gold NM units in a heterodimer structure. Our analysis suggest abnormal shifts in the higher energy modes. We propose a method to analyze the behavior of multilayer concentric nanoshell particles in an antisymmetric orientation employing full dielectric function calculations and the Drude model based on interband transitions in metallic components. This study provides a method to predict the behavior of the higher energy plasmon resonant modes in entirely antisymmetric structures such as compositional heterodimers.

  6. Coherent resonance of quantum plasmons in Stone-Wales defected graphene-silver nanowire hybrid system

    Science.gov (United States)

    Liu, Tong; Zhang, Hong; Cheng, Xin-Lu; Xu, Yang

    2017-10-01

    Defected graphene has a more important practical significance than graphene. Silver nanoparticles can modify the optical properties of defected graphene. We present herein a detailed theoretical analysis about the coherent resonance of quantum plasmons in the Stone-Wales (SW) defected graphene-silver nanowire hybrid system by using time-dependent density functional theory. The plasmon coherent effect is mainly attributed to the electromagnetic field coupling between the Stone-Wales defected graphene and silver nanowires. As a result, the optical response of the hybrid system exhibits a remarkable enhancement. Plasmon resonance, which depends on polarization and selectable tuning, is enhanced in wide frequency regions. Moreover, it reveals that the resonance frequency of an optical absorption spectrum depends on the space configuration of the SW defected graphene in the hybrid system. This investigation provides a better understanding of the plasmon enhancement effect used in a graphene-based photoelectric device. The study also offers an effective means of detecting the defects existing in graphene.

  7. Optical Twist Induced by Plasmonic Resonance

    Science.gov (United States)

    Chen, Jun; Wang, Neng; Cui, Liyong; Li, Xiao; Lin, Zhifang; Ng, Jack

    2016-06-01

    Harvesting light for optical torque is of significant importance, owing to its ability to rotate nano- or micro-objects. Nevertheless, applying a strong optical torque remains a challenging task: angular momentum must conserve but light is limited. A simple argument shows the tendency for two objects with strong mutual scattering or light exchange to exhibit a conspicuously enhanced optical torque without large extinction or absorption cross section. The torque on each object is almost equal but opposite, which we called optical twist. The effect is quite significant for plasmonic particle cluster, but can also be observed in structures with other morphologies. Such approach exhibits an unprecedentedly large torque to light extinction or absorption ratio, enabling limited light to exert a relatively large torque without severe heating. Our work contributes to the understanding of optical torque and introduces a novel way to manipulate the internal degrees of freedom of a structured particle cluster.

  8. Plasmon resonance in warm dense matter

    Energy Technology Data Exchange (ETDEWEB)

    Thiele, R; Bornath, T; Fortmann, C; Holl, A; Redmer, R; Reinholz, H; Ropke, G; Wierling, A; Glenzer, S H; Gregori, G

    2008-02-21

    Collective Thomson scattering with extreme ultraviolet light or x-rays is shown to allow for a robust measurement of the free electron density in dense plasmas. Collective excitations like plasmons appear as maxima in the scattering signal. Their frequency position can directly be related to the free electron density. The range of applicability of the standard Gross-Bohm dispersion relation and of an improved dispersion relation in comparison to calculations based on the dielectric function in random phase approximation is investigated. More important, this well-established treatment of Thomson scattering on free electrons is generalized in the Born-Mermin approximation by including collisions. We show that, in the transition region from collective to non-collective scattering, the consideration of collisions is important.

  9. Detection of Penicillin via Surface Plasmon Resonance Biosensor

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ying; MU Ying; JIN Wei; YANG Meng-chao; ZHANG Ti-qiang; ZHOU Chao; XIE Fei; SONG Qi; REN Hao; JIN Qin-han

    2012-01-01

    A method of using Au colloid to capture the decomposed product of penicillin,penicillamine,on a surface plasmon resonance(SPR) biosensor for the quantitative determination of penicillin was developed.Based on the decomposition of penicillin to generate penicillamine and penilloaldehyde,a high seositive biosensor for detecting penicillin was also developed.In our experiment,it was penicillamine rather than penicillin that has been measured.This is because penicillamine contains a functional group that makes it self-assembling on Au colloid to increase the molecular weight so as to improve the surface plasmon resonance signal.On a UV-Vis spectrophotometer,a high concentration of penicilliamine-Au complex was determined,indicating that penicillamine was already well combined with Au colloid.The method,using the combination of Au colloid with penicillamine,proved to detect penicillin.

  10. Optical Torque from Enhanced Scattering by Multipolar Plasmonic Resonance

    CERN Document Server

    Lee, Yoonkyung E; Jin, Dafei; Fang, Nicholas

    2014-01-01

    We present a theoretical study of the optical angular momentum transfer from a circularly polarized plane wave to thin metal nanoparticles of different rotational symmetries. While absorption has been regarded as the predominant mechanism of torque generation on the nanoscale, we demonstrate numerically how the contribution from scattering can be enhanced by using multipolar plasmon resonance. The multipolar modes in non-circular particles can convert the angular momentum carried by the scattered field, thereby producing scattering-dominant optical torque, while a circularly symmetric particle cannot. Our results show that the optical torque induced by resonant scattering can contribute to 80% of the total optical torque in gold particles. This scattering-dominant torque generation is extremely mode-specific, and deserves to be distinguished from the absorption-dominant mechanism. Our findings might have applications in optical manipulation on the nanoscale as well as new designs in plasmonics and metamateria...

  11. Absorption enhancement in amorphous silicon thin films via plasmonic resonances in nickel silicide nanoparticles

    Science.gov (United States)

    Hachtel, Jordan; Shen, Xiao; Pantelides, Sokrates; Sachan, Ritesh; Gonzalez, Carlos; Dyck, Ondrej; Fu, Shaofang; Kalnayaraman, Ramki; Rack, Phillip; Duscher, Gerd

    2013-03-01

    Silicon is a near ideal material for photovoltaics due to its low cost, abundance, and well documented optical properties. The sole detriment of Si in photovoltaics is poor absorption in the infrared. Nanoparticle surface plasmon resonances are predicted to increase absorption by scattering to angles greater than the critical angle for total internal reflection (16° for a Si/air interface), trapping the light in the film. Experiments confirm that nickel silicide nanoparticles embedded in amorphous silicon increases absorption significantly in the infrared. However, it remains to be seen if electron-hole pair generation is increased in the solar cell, or whether the light is absorbed by the nanoparticles themselves. The nature of the absorption is explored by a study of the surface plasmon resonances through electron energy loss spectrometry and scanning transmission electron microscopy experiments, as well as first principles density functional theory calculations. Initial experimental results do not show strong plasmon resonances on the nanoparticle surfaces. Calculations of the optical properties of the nickel silicide particles in amorphous silicon are performed to understand why this resonance is suppressed. Work supported by NSF EPS 1004083 (TN-SCORE).

  12. Sub-micron surface plasmon resonance sensor systems

    Science.gov (United States)

    Glazier, James A. (Inventor); Amarie, Dragos (Inventor)

    2013-01-01

    Wearable or implantable devices combining microfluidic control of sample and reagent flow and micro-cavity surface plasmon resonance sensors functionalized with surface treatments or coatings capable of specifically binding to target analytes, ligands, or molecules in a bodily fluid are provided. The devices can be used to determine the presence and concentration of target analytes in the bodily fluids and thereby help diagnose, monitor or detect changes in disease conditions.

  13. Tuning the localized surface plasmon resonance of silver nanoplatelet colloids

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Asha; Jayabalan, J; Chari, Rama [Laser Physics Applications Division, Raja Ramanna Centre for Advanced Technology, Indore (India); Srivastava, Himanshu [Indus Synchrotrons Utilization Division, Raja Ramanna Centre for Advanced Technology, Indore (India); Oak, S M, E-mail: jjaya@rrcat.gov.i [Solid State Laser Division, Raja Ramanna Centre for Advanced Technology, Indore (India)

    2010-08-25

    The effect of femtosecond laser irradiation on silver nanoplatelet colloids is described. It is shown that irradiation with a femtosecond laser of appropriate fluence can be used to tune the localized surface plasmon resonances of triangular silver nanoplatelets by a few tens of nanometres. This peak shift is shown to be caused by the structural modifications of the particle tips. We have also shown that post-preparation addition of poly-vinyl pyrrolidone to the nanocolloid arrests the peak shift.

  14. Plasmonic Properties of Nanostructured Diamond Like Carbon/Silver Nanocomposite Films with Nanohole Arrays

    Directory of Open Access Journals (Sweden)

    Šarūnas MEŠKINIS

    2016-11-01

    Full Text Available Plasmonic properties of the diamond like carbon nanocomposite films with embedded silver nanoparticles with patterned nanohole arrays were analyzed in this study. The films were deposited by unbalanced reactive magnetron sputtering of silver target. Nanopatterning of the films was performed by combining electron beam nanolithography and ion beam etching techniques. Modeling of plasmonic properties was done using the classical Maxwell-Garnett theory. Modeling data and experimental results were in good accordance. Formation of the nanohole pattern in diamond like carbon films doped with silver resulted in decreased intensity of the surface plasmon resonance absorbance peak. No new absorbance or transmittance peaks were observed after the nanopattering. It was explained by extraordinary transmission effect in nanostructured DLC : Ag film films due to plasmon polariton resonance inside of the nanoholes.DOI: http://dx.doi.org/10.5755/j01.ms.22.4.13193

  15. Super-Period Gold Nanodisc Grating-Enabled Surface Plasmon Resonance Spectrometer Sensor.

    Science.gov (United States)

    Tian, Xueli; Guo, Hong; Bhatt, Ketan H; Zhao, Song Q; Wang, Yi; Guo, Junpeng

    2015-10-01

    We experimentally demonstrate a surface plasmon resonance spectrometer sensor by using an e-beam-patterned super-period gold nanodisc grating on a glass substrate. The super-period gold nanodisc grating has a small subwavelength period and a large diffraction grating period. The small subwavelength period enhances localized surface plasmon resonance, and the large diffraction grating period diffracts surface plasmon resonance radiation into different directions corresponding to different wavelengths. Surface plasmon resonance spectra are measured in the first order diffraction spatial profiles captured by a charge-coupled device (CCD) in addition to the traditional way of measurement using an external optical spectrometer in the zeroth order transmission. A surface plasmon resonance sensor for the bovine serum albumin protein nanolayer bonding is demonstrated by measuring the surface plasmon resonance shift in the first order diffraction spatial intensity profiles captured by the CCD.

  16. Resonant enhancement of Raman scattering in metamaterials with hybrid electromagnetic and plasmonic resonances

    Science.gov (United States)

    Guddala, Sriram; Narayana Rao, D.; Ramakrishna, S. Anantha

    2016-06-01

    A tri-layer metamaterial perfect absorber of light, consisting of (Al/ZnS/Al) films with the top aluminum layer patterned as an array of circular disk nanoantennas, is investigated for resonantly enhancing Raman scattering from C60 fullerene molecules deposited on the metamaterial. The metamaterial is designed to have resonant bands due to plasmonic and electromagnetic resonances at the Raman pump frequency (725 nm) as well as Stokes emission bands. The Raman scattering from C60 on the metamaterial with resonantly matched bands is measured to be enhanced by an order of magnitude more than C60 on metamaterials with off-resonant absorption bands peaking at 1090 nm. The Raman pump is significantly enhanced due to the resonance with a propagating surface plasmon band, while the highly impedance-matched electromagnetic resonance is expected to couple out the Raman emission efficiently. The nature and hybridization of the plasmonic and electromagnetic resonances to form compound resonances are investigated by numerical simulations.

  17. Inductive tuning of Fano-resonant metasurfaces using plasmonic response of graphene in the mid-infrared.

    Science.gov (United States)

    Mousavi, S Hossein; Kholmanov, Iskandar; Alici, Kamil B; Purtseladze, David; Arju, Nihal; Tatar, Kaya; Fozdar, David Y; Suk, Ji Won; Hao, Yufeng; Khanikaev, Alexander B; Ruoff, Rodney S; Shvets, Gennady

    2013-03-13

    Graphene is widely known for its anomalously strong broadband optical absorptivity of 2.3% that enables seeing its single-atom layer with the naked eye. However, in the mid-infrared part of the spectrum graphene represents a quintessential lossless zero-volume plasmonic material. We experimentally demonstrate that, when integrated with Fano-resonant plasmonic metasurfaces, single-layer graphene (SLG) can be used to tune their mid-infrared optical response. SLG's plasmonic response is shown to induce large blue shifts of the metasurface's resonance without reducing its spectral sharpness. This effect is explained by a generalized perturbation theory of SLG-metamaterial interaction that accounts for two unique properties of the SLG that set it apart from all other plasmonic materials: its anisotropic response and zero volume. These results pave the way to using gated SLG as a platform for dynamical spectral tuning of infrared metamaterials and metasurfaces.

  18. Resonant scattering of surface plasmon polaritons by dressed quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Danhong; Cardimona, Dave [Air Force Research Laboratory, Space Vehicles Directorate, Kirtland Air Force Base, New Mexico 87117 (United States); Easter, Michelle [Department of Mechanical Engineering, Stevens Institute of Technology, 1 Castle Point Terrace, Hoboken, New Jersey 07030 (United States); Gumbs, Godfrey [Department of Physics and Astronomy, Hunter College of the City University of New York, 695 Park Avenue, New York, New York 10065 (United States); Maradudin, A. A. [Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States); Lin, Shawn-Yu [Department of Electrical, Computer and Systems Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180 (United States); Zhang, Xiang [Department of Mechanical Engineering, 3112 Etcheverry Hall, University of California at Berkeley, Berkeley, California 94720 (United States)

    2014-06-23

    The resonant scattering of surface plasmon-polariton waves (SPP) by embedded semiconductor quantum dots above the dielectric/metal interface is explored in the strong-coupling regime. In contrast to non-resonant scattering by a localized dielectric surface defect, a strong resonant peak in the spectrum of the scattered field is predicted that is accompanied by two side valleys. The peak height depends nonlinearly on the amplitude of SPP waves, reflecting the feedback dynamics from a photon-dressed electron-hole plasma inside the quantum dots. This unique behavior in the scattered field peak strength is correlated with the occurrence of a resonant dip in the absorption spectrum of SPP waves due to the interband photon-dressing effect. Our result on the scattering of SPP waves may be experimentally observable and applied to spatially selective illumination and imaging of individual molecules.

  19. Suppression of surface plasmon resonance in Au nanoparticles upon transition to the liquid state.

    Science.gov (United States)

    Gerasimov, V S; Ershov, A E; Gavrilyuk, A P; Karpov, S V; Ågren, H; Polyutov, S P

    2016-11-14

    Significant suppression of resonant properties of single gold nanoparticles at the surface plasmon frequency during heating and subsequent transition to the liquid state has been demonstrated experimentally and explained for the first time. The results for plasmonic absorption of the nanoparticles have been analyzed by means of Mie theory using experimental values of the optical constants for the liquid and solid metal. The good qualitative agreement between calculated and experimental spectra support the idea that the process of melting is accompanied by an abrupt increase of the relaxation constants, which depends, beside electron-phonon coupling, on electron scattering at a rising number of lattice defects in a particle upon growth of its temperature, and subsequent melting as a major cause for the observed plasmonic suppression. It is emphasized that observed effect is fully reversible and may underlie nonlinear optical responses of nanocolloids and composite materials containing plasmonic nanoparticles and their aggregates in conditions of local heating and in general, manifest itself in a wide range of plasmonics phenomena associated with strong heating of nanoparticles.

  20. Control of the plasmonic resonance of a graphene coated plasmonic nanoparticle array combined with a nematic liquid crystal

    Science.gov (United States)

    De Sio, Luciano; Cataldi, Ugo; Bürgi, Thomas; Tabiryan, Nelson; Bunning, Timothy J.

    2016-07-01

    We report on the fabrication and characterization of a switchable plasmonic device based on a conductive graphene oxide (cGO) coated plasmonic nanoparticle (NP) array, layered with nematic liquid crystal (NLC) as an active medium. A monolayer of NPs has been immobilized on a glass substrate through electrostatic interaction, and then grown in place using nanochemistry. This monolayer is then coated with a thin (less then 100nm) cGO film which acts simultaneously as both an electro-conductive and active medium. The combination of the conductive NP array with a separate top cover substrate having both cGO and a standard LC alignment layer is used for aligning a NLC film in a hybrid configuration. The system is analysed in terms of morphological and electro-optical properties. The spectral response of the sample characterized after each element is added (air, cGO, NLC) reveals a red-shift of the localized plasmonic resonance (LPR) frequency of approximately 62nm with respect to the NP array surrounded by air. The application of an external voltage (8Vpp) is suitable to modulate (blue shift) the LPR frequency by approximately 22nm.

  1. Graphene-plasmon polaritons: From fundamental properties to potential applications

    Science.gov (United States)

    Xiao, Sanshui; Zhu, Xiaolong; Li, Bo-Hong; Mortensen, N. Asger

    2016-04-01

    With unique possibilities for controlling light in nanoscale devices, graphene plasmonics has opened new perspectives to the nanophotonics community with potential applications in metamaterials, modulators, photodetectors, and sensors. In this paper, we briefly review the recent exciting progress in graphene plasmonics. We begin with a general description of the optical properties of graphene, particularly focusing on the dispersion of graphene-plasmon polaritons. The dispersion relation of graphene-plasmon polaritons of spatially extended graphene is expressed in terms of the local response limit with an intraband contribution. With this theoretical foundation of graphene-plasmon polaritons, we then discuss recent exciting progress, paying specific attention to the following topics: excitation of graphene plasmon polaritons, electron-phonon interactions in graphene on polar substrates, and tunable graphene plasmonics with applications in modulators and sensors. Finally, we address some of the apparent challenges and promising perspectives of graphene plasmonics.

  2. Mathematical analysis of plasmonic resonances for nanoparticles: The full Maxwell equations

    Science.gov (United States)

    Ammari, Habib; Ruiz, Matias; Yu, Sanghyeon; Zhang, Hai

    2016-09-01

    In this paper we use the full Maxwell equations for light propagation in order to analyze plasmonic resonances for nanoparticles. We mathematically define the notion of plasmonic resonance and analyze its shift and broadening with respect to changes in size, shape, and arrangement of the nanoparticles, using the layer potential techniques associated with the full Maxwell equations. We present an effective medium theory for resonant plasmonic systems and derive a condition on the volume fraction under which the Maxwell-Garnett theory is valid at plasmonic resonances.

  3. Chemically Tuning the Localized Surface Plasmon Resonances of Gold Nanostructure Arrays

    KAUST Repository

    Zheng, Yue Bing

    2009-04-30

    We report on chemical etching of ordered Au nanostructure arrays to continuously tune their localized surface plasmon resonances (LSPR). Real-time extinction spectra were recorded from both Au nanodisks and nanospheres immobilized on glass substrates when immersed in Au etchant. The time-dependent LSPR frequencies, intensities, and bandwidths were studied theoretically with discrete dipole approximations and the Mie solution, and they were correlated with the evolution of the etched Au nanostructures\\' morphology (as examined by atomic force microscopy). Since this chemical etching method can conveniently and accurately tune LSPR, it offers precise control of plasmonic properties and can be useful in applications such as surfaceenhanced Raman spectroscopy and molecular resonance spectroscopy. © 2009 American Chemical Society.

  4. Experimental evidence of localized plasmon resonance in composite materials containing single-wall carbon nanotubes

    Science.gov (United States)

    Shuba, M. V.; Paddubskaya, A. G.; Plyushch, A. O.; Kuzhir, P. P.; Slepyan, G. Ya.; Maksimenko, S. A.; Ksenevich, V. K.; Buka, P.; Seliuta, D.; Kasalynas, I.; Macutkevic, J.; Valusis, G.; Thomsen, C.; Lakhtakia, A.

    2012-04-01

    Experimental proof of localized plasmon resonance was found in thin films containing either single-walled carbon nanotubes (SWNT) or SWNT bundles of different length. All samples were prepared by a simple technique that permitted the selection of different SWNT lengths in different samples without significant differences in electronic properties. Fourier-transform infrared spectroscopy showed that an optical-density peak, the same as a terahertz conductivity peak, shifts to higher frequencies as the SWNT lengths are reduced—in agreement with a similar tendency predicted for the localized plasmon resonance in finite-length SWNTs [Slepyan , Phys. Rev. BPRBMDO1098-012110.1103/PhysRevB.81.205423 81, 205423 (2010)].

  5. Surface plasmon resonance biosensor based on large size square-lattice photonic crystal fiber

    Science.gov (United States)

    Bing, Pibin; Li, Zhongyang; Yuan, Sheng; Yao, Jianquan; Lu, Ying

    2016-04-01

    A surface plasmon resonance biosensor based on large size square-lattice photonic crystal fiber has been designed and simulated by finite element method. The square-lattice airholes are first coated with a calcium fluoride layer to provide mode confinement, then a nanoscale gold layer is deposited to excite the plasmon mode, and finally, the sample is infiltrated into the holes. The numerical results reveal that the resonance properties are easily affected by many parameters. The refractive index resolution of corresponding sensor can reach 4.3 × 10-6 RIU when the optimum parameters are set as the radius of curvature of the airhole r = 2 μm, the thickness of the core struts c = 200 nm, the auxiliary dielectric layer s = 1 μm, and the gold film d = 40 nm. In addition, the effective area and nonlinear coefficient are calculated.

  6. Anomalously strong plasmon resonances in aluminium bronze by modification of the electronic density-of-states

    Science.gov (United States)

    Shahcheraghi, N.; Keast, V. J.; Gentle, A. R.; Arnold, M. D.; Cortie, M. B.

    2016-10-01

    We use a combination of experimental measurements and density functional theory calculations to show that modification of the band structure of Cu by additions of Al causes an unexpected enhancement of the dielectric properties. The effect is optimized in alloys with Al contents between 10 and 15 at.% and would result in strong localized surface plasmon resonances at suitable wavelengths of light. This result is surprising as, in general, alloying of Cu increases its DC resistivity and would be expected to increase optical loss. The wavelengths for the plasmon resonances in the optimized alloy are significantly blue-shifted relative to those of pure Cu and provide a new material selection option for the range 2.2-2.8 eV.

  7. Colorimetric plasmon resonance microfluidics on nanohole array sensors

    Directory of Open Access Journals (Sweden)

    Austin Hsiao

    2015-09-01

    Full Text Available We present the label-free colorimetric visualization in microfluidics using plasmon resonance on a large-area and over a wide field-of-view (>100 mm2 nanohole array device called nanoLycurgus Cup Array (nanoLCA. We demonstrate the spectral detection and colorimetric sensing of static solutions of different concentrations of glycerol–water confined in parallel microfluidic channels integrated with nanoLCA. Taking advantage of the large sensor area and the colorimetric sensing capability of nanoLCA, we visualize in real-time the modulation of two immiscible solutions (water and oil, generated with integrated flow-focus microfluidics, in a label-free manner. Finite Element Method (FEM based simulation tool (COMSOL was used to verify the droplet formation in the microfluidics. Finite Difference Time Domain (FDTD electromagnetic simulation was used to identify the resonance modes of the plasmonic sensor. Finally, we demonstrate the real-time monitoring of streptavidin–biotin biomolecular interaction with the plasmonic biosensor.

  8. Nanostructured surfaces for surface plasmon resonance spectroscopy and imaging

    Science.gov (United States)

    Petefish, Joseph W.

    Surface plasmon resonance (SPR) has achieved widespread recognition as a sensitive, label-free, and versatile optical method for monitoring changes in refractive index at a metal-dielectric interface. Refractive index deviations of 10-6 RIU are resolvable using SPR, and the method can be used in real-time or ex-situ. Instruments based on carboxymethyl dextran coated SPR chips have achieved commercial success in biological detection, while SPR sensors can also be found in other fields as varied as food safety and gas sensing. Chapter 1 provides a physical background of SPR sensing. A brief history of the technology is presented, and publication data are included that demonstrate the large and growing interest in surface plasmons. Numerous applications of SPR sensors are listed to illustrate the broad appeal of the method. Surface plasmons (SPs) and surface plasmon polaritions (SPPs) are formally defined, and important parameters governing their spatial behavior are derived from Maxwell's equations and appropriate boundary conditions. Physical requirements for exciting SPs with incident light are discussed, and SPR imaging is used to illustrate the operating principle of SPR-based detection. Angle-tunable surface enhanced infrared absorption (SEIRA) of polymer vibrational modes via grating-coupled SPR is demonstrated in Chapter 2. Over 10-fold enhancement of C-H stretching modes was found relative to the absorbance of the same film in the absence of plasmon excitation. Modeling results are used to support and explain experimental observations. Improvements to the grating coupler SEIRA platform in Chapter 2 are explored in Chapters 3 and 4. Chapter 3 displays data for two sets of multipitch gratings: one set with broadly distributed resonances with the potential for multiband IR enhancement and the other with finely spaced, overlapping resonances to form a broadband IR enhancement device. Diffraction gratings having multiple periods were fabricated using a Lloyd

  9. Plasmonic doped semiconductor nanocrystals: Properties, fabrication, applications and perspectives

    Science.gov (United States)

    Kriegel, Ilka; Scotognella, Francesco; Manna, Liberato

    2017-02-01

    Degenerately doped semiconductor nanocrystals (NCs) are of recent interest to the NC community due to their tunable localized surface plasmon resonances (LSPRs) in the near infrared (NIR). The high level of doping in such materials with carrier densities in the range of 1021cm-3 leads to degeneracy of the doping levels and intense plasmonic absorption in the NIR. The lower carrier density in degenerately doped semiconductor NCs compared to noble metals enables LSPR tuning over a wide spectral range, since even a minor change of the carrier density strongly affects the spectral position of the LSPR. Two classes of degenerate semiconductors are most relevant in this respect: impurity doped semiconductors, such as metal oxides, and vacancy doped semiconductors, such as copper chalcogenides. In the latter it is the density of copper vacancies that controls the carrier concentration, while in the former the introduction of impurity atoms adds carriers to the system. LSPR tuning in vacancy doped semiconductor NCs such as copper chalcogenides occurs by chemically controlling the copper vacancy density. This goes in hand with complex structural modifications of the copper chalcogenide crystal lattice. In contrast the LSPR of degenerately doped metal oxide NCs is modified by varying the doping concentration or by the choice of host and dopant atoms, but also through the addition of capacitive charge carriers to the conduction band of the metal oxide upon post-synthetic treatments, such as by electrochemical- or photodoping. The NIR LSPRs and the option of their spectral fine-tuning make accessible important new features, such as the controlled coupling of the LSPR to other physical signatures or the enhancement of optical signals in the NIR, sensing application by LSPR tracking, energy production from the NIR plasmon resonance or bio-medical applications in the biological window. In this review we highlight the recent advances in the synthesis of various different plasmonic

  10. Gold Nanoplates for a Localized Surface Plasmon Resonance-Based Boric Acid Sensor.

    Science.gov (United States)

    Morsin, Marlia; Mat Salleh, Muhamad; Ali Umar, Akrajas; Sahdan, Mohd Zainizan

    2017-04-25

    Localized surface plasmon resonance (LSPR) properties of metallic nanostructures, such as gold, are very sensitive to the dielectric environment of the material, which can simply be adjusted by changing its shape and size through modification of the synthesizing process. Thus, these unique properties are very promising, particularly for the detection of various types of chemicals, for example boric acid which is a non-permitted preservative employed in food preparations. For the sensing material, gold (Au) nanoplates with a variety of shapes, i.e., triangular, hexagonal, truncated pentagon and flat rod, were prepared using a seed-mediated growth method. The yield of Au nanoplates was estimated to be ca. 63% over all areas of the sensing material. The nanoplates produced two absorption bands, i.e., the transverse surface plasmon resonance (t-SPR) and the longitudinal surface plasmon resonance (l-SPR) at 545 nm and 710 nm, respectively. In the sensing study, these two bands were used to examine the response of gold nanoplates to the presence of boric acid in an aqueous environment. In a typical process, when the sample is immersed into an aqueous solution containing boric acid, these two bands may change their intensity and peak centers as a result of the interaction between the boric acid and the gold nanoplates. The changes in the intensities and peak positions of t-SPR and l-SPR linearly correlated with the change in the boric acid concentration in the solution.

  11. Simultaneous surface plasmon resonance and x-ray absorption spectroscopy

    Science.gov (United States)

    Serrano, A.; Rodríguez de la Fuente, O.; Collado, V.; Rubio-Zuazo, J.; Monton, C.; Castro, G. R.; García, M. A.

    2012-08-01

    We present an experimental setup for the simultaneous measurement of surface plasmon resonance (SPR) and x-ray absorption spectroscopy (XAS) on metallic thin films at a synchrotron beamline. The system allows measuring in situ and in real time the effect of x-ray irradiation on the SPR curves to explore the interaction of x-rays with matter. It is also possible to record XAS spectra while exciting SPR in order to study changes in the films induced by the excitation of surface plasmons. Combined experiments recording simultaneously SPR and XAS curves while scanning different parameters can be also carried out. The relative variations in the SPR and XAS spectra that can be detected with this setup range from 10-3 to 10-5, depending on the particular experiment.

  12. Simultaneous Surface Plasmon Resonance and X-ray Absorption Spectroscopy

    CERN Document Server

    Serrano, A; Collado, V; Rubio-Zuazo, J; Monton, C; Castro, G; García, M A

    2012-01-01

    We present here an experimental set-up to perform simultaneously measurements of surface plasmon resonance (SPR) and X-ray absorption spectroscopy (XAS) in a synchrotron beamline. The system allows measuring in situ and in real time the effect of X-ray irradiation on the SPR curves to explore the interaction of X-rays with matter. It is also possible to record XAS spectra while exciting SPR in order to detect the changes in the electronic configuration of thin films induced by the excitation of surface plasmons. Combined experiments recording simultaneously SPR and XAS curves while scanning different parameters can be carried out. The relative variations in the SPR and XAS spectra that can be detected with this set-up ranges from 10-3 to 10-5, depending on the particular experiment.

  13. Simultaneous surface plasmon resonance and x-ray absorption spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Serrano, A. [Instituto de Ceramica y Vidrio (ICV-CSIC), Cantoblanco, 28049 Madrid (Spain); Departamento de Fisica de Materiales, Universidad Complutense de Madrid, 28040 Madrid (Spain); Rodriguez de la Fuente, O. [Departamento de Fisica de Materiales, Universidad Complutense de Madrid, 28040 Madrid (Spain); Collado, V.; Rubio-Zuazo, J.; Castro, G. R. [SpLine, Spanish CRG Beamline at the ESRF, F-38043 Grenoble, Cedex 09, France and Instituto de Ciencia de Materiales de Madrid, (ICMM-CSIC), Cantoblanco, 28049 Madrid (Spain); Monton, C. [Department of Physics and Center for Advanced Nanoscience, University of California San Diego, La Jolla, California 92093 (United States); Garcia, M. A. [Instituto de Ceramica y Vidrio (ICV-CSIC), Cantoblanco, 28049 Madrid (Spain); IMDEA Nanociencia, Cantoblanco, 28049 Madrid (Spain)

    2012-08-15

    We present an experimental setup for the simultaneous measurement of surface plasmon resonance (SPR) and x-ray absorption spectroscopy (XAS) on metallic thin films at a synchrotron beamline. The system allows measuring in situ and in real time the effect of x-ray irradiation on the SPR curves to explore the interaction of x-rays with matter. It is also possible to record XAS spectra while exciting SPR in order to study changes in the films induced by the excitation of surface plasmons. Combined experiments recording simultaneously SPR and XAS curves while scanning different parameters can be also carried out. The relative variations in the SPR and XAS spectra that can be detected with this setup range from 10{sup -3} to 10{sup -5}, depending on the particular experiment.

  14. Coupling single quantum dots to plasmonic nanocones: optical properties.

    Science.gov (United States)

    Meixner, Alfred J; Jäger, Regina; Jäger, Sebastian; Bräuer, Annika; Scherzinger, Kerstin; Fulmes, Julia; Krockhaus, Sven zur Oven; Gollmer, Dominik A; Kern, Dieter P; Fleischer, Monika

    2015-01-01

    Coupling a single quantum emitter, such as a fluorescent molecule or a quantum dot (QD), to a plasmonic nanostructure is an important issue in nano-optics and nano-spectroscopy, relevant for a wide range of applications, including tip-enhanced near-field optical microscopy, plasmon enhanced molecular sensing and spectroscopy, and nanophotonic amplifiers or nanolasers, to mention only a few. While the field enhancement of a sharp nanoantenna increasing the excitation rate of a very closely positioned single molecule or QD has been well investigated, the detailed physical mechanisms involved in the emission of a photon from such a system are, by far, less investigated. In one of our ongoing research projects, we try to address these issues by constructing and spectroscopically analysing geometrically simple hybrid heterostructures consisting of sharp gold cones with single quantum dots attached to the very tip apex. An important goal of this work is to tune the longitudinal plasmon resonance by adjusting the cones' geometry to the emission maximum of the core-shell CdSe/ZnS QDs at nominally 650 nm. Luminescence spectra of the bare cones, pure QDs and hybrid systems were distinguished successfully. In the next steps we will further investigate, experimentally and theoretically, the optical properties of the coupled systems in more detail, such as the fluorescence spectra, blinking statistics, and the current results on the fluorescence lifetimes, and compare them with uncoupled QDs to obtain a clearer picture of the radiative and non-radiative processes.

  15. Fano resonance in graphene-MoS2 heterostructure-based surface plasmon resonance biosensor and its potential applications

    Science.gov (United States)

    Zheng, Gaige; Zou, Xiujuan; Chen, Yunyun; Xu, Linhua; Rao, Weifeng

    2017-04-01

    We propose a new configuration of surface plasmon resonance (SPR) sensor that is based on graphene-MoS2 hybrid structures for ultrasensitive detection of molecules. The present configuration is consisted of chalcogenide glass (2S2G) prism, Ag, coupling layer, guiding layer, graphene-MoS2 heterostructure and analyte. We perform numerical and analytical study of the impact of the thickness and refractive index (RI) of the coupling and guiding layer in a planar sensing structure within the Kretschmann configuration on the resonance properties of the excitation. Results of reflectivity calculations clearly demonstrate the sharp Fano-type resonance appears in the curve of SPR because of the coupling between surface plasmon polariton (SPP) and planar waveguide (PWG) modes. The properties of the Fano resonance (FR) strongly depend on the parameters of the structure. The calculated magnetic field profiles manifest that the hybrid nature of the electromagnetic (EM) modes excited in the present structure. The proposed system displays an enhancement factor of sensitivity by intensity more than 2 × 103-fold when compared to the SPR sensing scheme.

  16. The nature of transmission resonances in plasmonic metallic gratings

    CERN Document Server

    D'Aguanno, G; Bloemer, M J; de Ceglia, D; Vincenti, M A; Alu', A

    2010-01-01

    Using the Fourier modal method (FMM) we report our analysis of the transmission resonances of a plasmonic grating with sub-wavelength period and extremely narrow slits for wavelengths of the incoming, transverse magnetic (TM)-polarized, radiation ranging from 240nm to 1500nm and incident angles from 0 degree to 90 degree. In particular, we study the case of a silver grating placed in vacuo. Consistent with previous studies on the topic, we highlight that the main mechanism for extraordinary transmission is a TM-Fabry-Perot (FP) branch supported by waveguide modes inside each slit. The TM-FP branch may also interact with surface plasmons (SPs) at the air/Ag interface through the reciprocal lattice vectors of the grating, for periods comparable with the incoming wavelength. When the TM-FP branch crosses a SP branch, a band gap is formed along the line of the SP dispersion. The gap has a Fano-Feshbach resonance at the low frequency band edge and a ridge resonance with extremely long lifetime at the high frequenc...

  17. Graphene plasmonics: multiple sharp Fano resonances in silver split concentric nanoring/disk resonator dimers on a metasurface

    Science.gov (United States)

    Ahmadivand, Arash; Sinha, Raju; Pala, Nezih

    2015-08-01

    We introduce a platform based on plasmonic metamaterials to design various optical devices. A simple structure brokenring with a nanodisk at the center is utilized to excite and hybridize the plasmon resonant modes. We show that the proposed nanoantenna is able to support strong sub- and superradiant plasmon resonances because of its unique geometrical features. Using the concentric ring/disk in a dimer orientation as a nanoantenna on a multilayer metasurface consisting of graphene monolayer, we induced double sharp plasmonic Fano resonant modes in the transmission window across the visible to the near-infrared region. Considering the strong polarization-dependency of the broken-ring/disk dimer antenna, it is shown that the proposed plasmonic metamaterial can be tailored as an optical router device for fast switching applications. This understanding opens new paths to employ plasmonic metamaterials with simple geometrical nanoscale blocks for sensing and switching applications.

  18. Structural and plasmonic properties of gold nanocrystals

    Science.gov (United States)

    Sivapalan, Sean T.

    The design of gold nanoparticles for surface-enhanced Raman scattering (SERS) and plasmonic enhanced fluorescence are more involved than simply maximizing the local field enhancement. The enhancement is a function of the excitation wavelength relative to the plasmon resonance as well as the distance of the reporter molecules from the nanoparticles' surface. For suspension based measurements, additional considerations must also be made regarding absorption and scattering effects as light propagates through the sample. These effects are in addition to the other more commonly observed effects such as nanocrystal shape. With such a wide number of variables in play, a series of studies breaking down each of these components and their contribution to the observed enhancement is warranted. In this thesis, a series of experiments were undertaken using a platform based on polyelectrolyte coating of gold nanoparticles by layer-by-layer deposition. The reporter molecules are bound onto the surface of polyelectrolyte coated nanoparticles before trap coating them with an additional oppositely charged polyelectrolyte layer. By etching away the gold nanoparticle using potassium cyanide, we are then able to quantify the number of reporter molecule per nanoparticle using mass spectrometry. With this quantitative approach, we can the directly compare the effects of the aforementioned enhancement mechanisms on the observed signal intensity. This method overcomes some of the disparities in literature between reported values of enhancement due to assumption in the number of reporter molecules contribution to the signal intensity. Using our group's expertise, we synthesized gold nanoparticle libraries of nanorods, cubes, trisoctahedra and spheres of different sizes. Each geometric configuration was characterized using a recently developed TEM technique---nano-beam coherent area diffraction. The as-synthesized were exposed to a coherent electron beam with probe size similar to that of

  19. Diffuse Surface Scattering in the Plasmonic Resonances of Ultra-Low Electron Density Nanospheres

    CERN Document Server

    Monreal, R Carmina; Apell, S Peter

    2015-01-01

    Localized surface plasmon resonances (LSPRs) have recently been identified in extremely diluted electron systems obtained by doping semiconductor quantum dots. Here we investigate the role that different surface effects, namely electronic spill-out and diffuse surface scattering, play in the optical properties of these ultra-low electron density nanosystems. Diffuse scattering originates from imperfections or roughness at a microscopic scale on the surface. Using an electromagnetic theory that describes this mechanism in conjunction with a dielectric function including the quantum size effect, we find that the LSPRs show an oscillatory behavior both in position and width for large particles and a strong blueshift in energy and an increased width for smaller radii, consistent with recent experimental results for photodoped ZnO nanocrystals. We thus show that the commonly ignored process of diffuse surface scattering is a more important mechanism affecting the plasmonic properties of ultra-low electron density ...

  20. Nanoscale Plasmonic Devices Based on Metal-Dielectric-Metal Stub Resonators

    Directory of Open Access Journals (Sweden)

    Yin Huang

    2012-01-01

    Full Text Available We review some of the recent research activities on plasmonic devices based on metal-dielectric-metal (MDM stub resonators for manipulating light at the nanoscale. We first introduce slow-light subwavelength plasmonic waveguides based on plasmonic analogues of periodically loaded transmission lines and electromagnetically induced transparency. In both cases, the structures consist of a MDM waveguide side-coupled to periodic arrays of MDM stub resonators. We then introduce absorption switches consisting of a MDM plasmonic waveguide side-coupled to a MDM stub resonator filled with an active material.

  1. Nanobiosensors Based on Localized Surface Plasmon Resonance for Biomarker Detection

    Directory of Open Access Journals (Sweden)

    Yoochan Hong

    2012-01-01

    Full Text Available Localized surface plasmon resonance (LSPR is induced by incident light when it interacts with noble metal nanoparticles that have smaller sizes than the wavelength of the incident light. Recently, LSPR-based nanobiosensors were developed as tools for highly sensitive, label-free, and flexible sensing techniques for the detection of biomolecular interactions. In this paper, we describe the basic principles of LSPR-based nanobiosensing techniques and LSPR sensor system for biomolecule sensing. We also discuss the challenges using LSPR nanobiosensors for detection of biomolecules as a biomarker.

  2. Encoded and multiplexed surface plasmon resonance sensor platform.

    Science.gov (United States)

    Kastl, Katja F; Lowe, Christopher R; Norman, Carl E

    2008-10-15

    We present a flexible new sensor system that combines the joint advantages of (i) discretely functionalized, code-bearing, microparticles and (ii) label-free detection using grating-coupled surface plasmon resonance. This system offers the possibility of simultaneously investigating the real-time binding kinetics of a variety of molecular interactions. One single multiplexed assay could employ a wide range of immobilization chemistries, surface preparation methods, and formats. Thus, the new system offers a very high level of assay conformability to the end user, particularly when compared to fixed microarrays.

  3. Surface plasmon resonance imaging for parallelized detection of protein biomarkers

    Science.gov (United States)

    Piliarik, Marek; Párová, Lucie; Vaisocherová, Hana; Homola, Jiří

    2009-05-01

    We report a novel high-throughput surface plasmon resonance (SPR) biosensor for rapid and parallelized detection of protein biomarkers. The biosensor is based on a high-performance SPR imaging sensor with polarization contrast and internal referencing which yields a considerably higher sensitivity and resolution than conventional SPR imaging systems (refractive index resolution 2 × 10-7 RIU). We combined the SPR imaging biosensor with microspotting to create an array of antibodies. DNA-directed protein immobilization was utilized for the spatially resolved attachment of antibodies. Using Human Chorionic Gonadotropin (hCG) as model protein biomarker, we demonstrated the potential for simultaneous detection of proteins in up to 100 channels.

  4. Surface Plasmon Resonance Sensors Based on Polymer Optical Fiber

    Institute of Scientific and Technical Information of China (English)

    Rong-Sheng Zheng; Yong-Hua Lu; Zhi-Guo Xie; Jun Tao; Kai-Qun Lin; Hai Ming

    2008-01-01

    Surface Plasmon Resonance (SPR) is a powerful technique for directly sensing in biological studies, chemical detection and environmental pollution monitoring. In this paper, we present polymer optical fiber application in SPR sensors, including wavelength interrogation surface enhanced Raman scattering SPR sensor and surface enhanced Raman scattering (SERS) probe.Long-period fiber gratings are fabricated on single mode polymer optical fiber (POF) with 120 μm period and 50% duty cycle. The polarization characteristic of this kind of birefringent grating is studied. Theoretical analysis shows it will be advantageous in SPR sensing applications.

  5. Optical cavity coupled surface plasmon resonance sensing for enhanced sensitivity

    Institute of Scientific and Technical Information of China (English)

    Zheng Zheng; Xin Zhao; Jinsong Zhu; Jim Diamond

    2008-01-01

    A surface plasmon resonance (SPR) sensing system based on the optical cavity enhanced detection tech-nique is experimentally demonstrated. A fiber-optic laser cavity is built with a SPR sensor inside. By measuring the laser output power when the cavity is biased near the threshold point, the sensitivity, defined as the dependence of the output optical intensity on the sample variations, can be increased by about one order of magnitude compared to that of the SPR sensor alone under the intensity interrogation scheme. This could facilitate ultra-high sensitivity SPR biosensing applications. Further system miniaturization is possible by using integrated optical components and waveguide SPR sensors.

  6. Graphene-plasmon polaritons: From fundamental properties to potential applications

    CERN Document Server

    Xiao, Sanshui; Li, Bo-Hong; Mortensen, N Asger

    2016-01-01

    With the unique possibilities for controlling light in nanoscale devices, graphene plasmonics has opened new perspectives to the nanophotonics community with potential applications in metamaterials, modulators, photodetectors, and sensors. This paper briefly reviews the recent exciting progress in graphene plasmonics. We begin with a general description for optical properties of graphene, particularly focusing on the dispersion of graphene-plasmon polaritons. The dispersion relation of graphene-plasmon polaritons of spatially extended graphene is expressed in terms of the local response limit with intraband contribution. With this theoretical foundation of graphene-plasmon polaritons, we then discuss recent exciting progress, paying specific attention to the following topics: excitation of graphene plasmon polaritons, electron-phonon interactions in graphene on polar substrates, and tunable graphene plasmonics with applications in modulators and sensors. Finally, we seek to address some of the apparent challe...

  7. Plasmon resonant gold-coated liposomes for spectrally coded content release

    OpenAIRE

    Leung, Sarah J.; Troutman, Timothy S.; Romanowski, Marek

    2009-01-01

    We have recently introduced liposome-supported plasmon resonant gold nanoshells (Troutman et al., Adv. Mater. 2008, 20, 2604–2608). These plasmon resonant gold-coated liposomes are degradable into components of a size compatible with renal clearance, potentially enabling their use as multifunctional agents in applications in nanomedicine, including imaging, diagnostics, therapy, and drug delivery. The present research demonstrates that laser illumination at the wavelength matching the plasmon...

  8. Polarimetric Properties of Optically Resonant Nanostructures

    Science.gov (United States)

    Theisen, Michael John

    Optically resonant nanostructures have been incorporated into a variety of devices used in a number of different fields. In this thesis, we explore optically resonant nanostructures in two forms. First we investigate a relatively new material, gallium implanted silicon (Si:Ga). We cover the fabrication process and experimentally find the optical properties as a function of both dose and wavelength. We then use the properties of this new material to create suspended arrays of Si:Ga nanowires, and determine their optical characteristics. In the second part of this thesis, we use more conventional materials and fabrication procedures to investigate the phase effects of guided mode resonators. We look at the spectral phase effects for a grating coupled silicon-on-insulator based guided mode resonator. We also look the angular phase effects of a surface plasmon polariton based guided mode resonator, comparing experimental results to theory calculated with rigorous coupled wave analysis for both cases. In addition, the guided mode resonance is modeled as a Fano resonance to gain insight into the functional form of the phase. Knowing the phase response of guided mode resonances may allow the creation of guided mode resonance based devices with higher sensitivity than traditional reflectance based devices.

  9. Study on Dielectric Function Models for Surface Plasmon Resonance Structure

    Directory of Open Access Journals (Sweden)

    Peyman Jahanshahi

    2014-01-01

    Full Text Available The most common permittivity function models are compared and identifying the best model for further studies is desired. For this study, simulations using several different models and an analytical analysis on a practical surface Plasmon structure were done with an accuracy of ∼94.4% with respect to experimental data. Finite element method, combined with dielectric properties extracted from the Brendel-Bormann function model, was utilized, the latter being chosen from a comparative study on four available models.

  10. Transparency windows of the plasmonic nanostructure composed of C-shaped and U-shaped resonators

    Science.gov (United States)

    Zhou, Xin; Ouyang, Min; Tang, Bin; Wang, Zhibing; He, Jun

    2017-02-01

    We in this study investigated numerically the plasmon-induced transparency (PIT) effect on the plasmonic nanostructures composed of C-shaped and U-shaped resonators by using finite difference time domain (FDTD) method. The PIT effect in the nanosystem stemmed from the near field coupling between the bright and dark modes. The nanostructure composed of three resonators exhibited double PIT effect. And the PIT spectral response of the proposed nanostructures was demonstrated having a dependence on the parameters of the compound plasmonic system such as the widths of C-shaped resonator and U-shaped resonator, the resonators spatial arrangement and the edge-to-edge distance between the adjacent resonators. The electric and magnetic field distributions of certain resonance wavelengths were also given to discuss the underlying physics. The resonator design strategy opens up a rich pathway to develop the building block of systems for all optical switching, plasmonic sensing applications.

  11. Tunable Dipole Surface Plasmon Resonances of Silver Nanoparticles by Cladding Dielectric Layers.

    Science.gov (United States)

    Liu, Xiaotong; Li, Dabing; Sun, Xiaojuan; Li, Zhiming; Song, Hang; Jiang, Hong; Chen, Yiren

    2015-07-28

    The tunability of surface plasmon resonance can enable the highest degree of localised surface plasmon enhancement to be achieved, based on the emitting or absorbing wavelength. In this article, tunable dipole surface plasmon resonances of Ag nanoparticles (NPs) are realized by modification of the SiO2 dielectric layer thicknesses. SiO2 layers both beneath and over the Ag NPs affected the resonance wavelengths of local surface plasmons (LSPs). By adjusting the SiO2 thickness beneath the Ag NPs from 5 nm to 20 nm, the dipole surface plasmon resonances shifted from 470 nm to 410 nm. Meanwhile, after sandwiching the Ag NPs by growing SiO2 before NPs fabrication and then overcoating the NPs with various SiO2 thicknesses from 5 nm to 20 nm, the dipole surface plasmon resonances changed from 450 nm to 490 nm. The SiO2 cladding dielectric layer can tune the Ag NP surface charge, leading to a change in the effective permittivity of the surrounding medium, and thus to a blueshift or redshift of the resonance wavelength. Also, the quadrupole plasmon resonances were suppressed by the SiO2 cladding layer because the dielectric SiO2 can suppress level splitting of surface plasmon resonances caused by the Ag NP coupling effect.

  12. Ultrathin suspended nanopores with surface plasmon resonance fabricated by combined colloidal lithography and film transfer.

    Science.gov (United States)

    Junesch, Juliane; Sannomiya, Takumi

    2014-05-14

    Suspended plasmonic nanopores in ultrathin film layers were fabricated through a simple and widely applicable method combining colloidal lithography and thin film transfer, which allows mass production of short-range ordered nanopore arrays on a large scale. By this combined method, mechanically stable and flexible free-standing nanopore membranes with a thickness down to 15-30 nm were produced. The plasmon resonances of the ultrathin plasmonic nanopores fabricated in AlN/Au/AlN trilayer and single layer Au membranes were tuned to lie in the vis-NIR wavelength range by properly designing their dimensions. The optical responses to the refractive index changes were tested and applied to adlayer sensing. The trilayer nanopore membrane showed a unique property to support water only on one side of the membrane, which was confirmed by the resonance shift and comparison with numerical simulation. Pore size reduction down to 10 nm can be achieved through additional material deposition. The filtering function of such pore-size-reduced conical shaped nanofunnels has also been demonstrated. The presented nanopore fabrication method offers new platforms for ultrathin nanopore sensing or filtering devices with controlled pore-size and optical properties. The film transfer technique employed in this work would enable the transformation of any substrate-based nanostructures to free-standing membrane based devices without complicated multiple etching processes.

  13. Plasmonic-Resonant Bowtie Antenna for Carbon Nanotube Photodetectors

    Directory of Open Access Journals (Sweden)

    Hongzhi Chen

    2012-01-01

    Full Text Available The design of bowtie antennas for carbon nanotube (CNT photodetectors has been investigated. CNT photodetectors have shown outstanding performance by using CNT as sensing element. However, detection wavelength is much larger than the diameter of the CNT, resulting in small fill factor. Bowtie antenna can confine light into a subwavelength volume based on plasmonic resonance, thus integrating a bowtie antenna to CNT photodetectors can highly improve photoresponse of the detectors. The electric field enhancement of bowtie antennas was calculated using the device geometry by considering fabrication difficulties and photodetector structure. It is shown that the electric field intensity enhancement increased exponentially with distance reduction between the CNT photodetector to the antenna. A redshift of the peak resonance wavelength is predicted due to the increase of tip angles of the bowtie antennas. Experimental results showed that photocurrent enhancement agreed well with theoretical calculations. Bowtie antennas may find wide applications in nanoscale photonic sensors.

  14. Surface plasmon resonance phenomenon of the insulating state polyaniline

    Energy Technology Data Exchange (ETDEWEB)

    Umiati, Ngurah Ayu Ketut, E-mail: ngurahayuketutumiati@gmail.com [Jurusan Fisika FMIPA UGM, Sekip Utara Yogyakarta, 55281 (Indonesia); Jurusan Fisika FMIPA Universitas Diponegoro, Jalan Prof. Soedarto, SH Tembalang Semarang 50275 (Indonesia); Triyana, Kuwat; Kamsul [Jurusan Fisika FMIPA UGM, Sekip Utara Yogyakarta, 55281 (Indonesia)

    2015-04-16

    Surface Plasmon Resonance (SPR) phenomenon of the insulating polyaniline (PANI) is has been observed. Surface Plasmon (SP) is the traveled electromagnetic wave that passes through the interface of dielectric metal and excited by attenuated total reflection (ATR) method in Kretschmannn configuration (Au-PANI prism). The resonance condition is observed through the angle of SPR in such condition that SP wave is coupled by the evanescent constant of laser beam. In this research, the laser beam was generated by He–Ne and its wavelength (λ) was 632,8 nm. SPR curve is obtained through observation of incidence angles of the laser beam in prism. SPR phenomenon at the boundary between Au – PANI layer has showed by reflection dip when the laser beam passes through the prism. In this early study, the observation was carried out through simulation Winspall 3.02 software and preliminary compared with some experimental data reported in other referred literatures. The results shows that the optimum layer of Au and polyaniline are 50 and 1,5 nm thick respectively. Our own near future experimental work would be further performed and reported elsewhere.

  15. Scattering-Type Surface-Plasmon-Resonance Biosensors

    Science.gov (United States)

    Wang, Yu; Pain, Bedabrata; Cunningham, Thomas; Seshadri, Suresh

    2005-01-01

    Biosensors of a proposed type would exploit scattering of light by surface plasmon resonance (SPR). Related prior biosensors exploit absorption of light by SPR. Relative to the prior SPR biosensors, the proposed SPR biosensors would offer greater sensitivity in some cases, enough sensitivity to detect bioparticles having dimensions as small as nanometers. A surface plasmon wave can be described as a light-induced collective oscillation in electron density at the interface between a metal and a dielectric. At SPR, most incident photons are either absorbed or scattered at the metal/dielectric interface and, consequently, reflected light is greatly attenuated. The resonance wavelength and angle of incidence depend upon the permittivities of the metal and dielectric. An SPR sensor of the type most widely used heretofore includes a gold film coated with a ligand a substance that binds analyte molecules. The gold film is thin enough to support evanescent-wave coupling through its thickness. The change in the effective index of refraction at the surface, and thus the change in the SPR response, increases with the number of bound analyte molecules. The device is illuminated at a fixed wavelength, and the intensity of light reflected from the gold surface opposite the ligand-coated surface is measured as a function of the angle of incidence. From these measurements, the angle of minimum reflection intensity is determined

  16. Synthesis and tuning of gold nanorods with surface plasmon resonance

    Science.gov (United States)

    Shajari, Daryush; Bahari, Ali; Gill, Pooria; Mohseni, Mojtaba

    2017-02-01

    Gold nanostructures in general and gold nanorods in particular due to their plasmon resonance has been employed for many applications, such as biosensors. For the biosensors uses, gold nanorods remain popular and reproducibility of them is the most important and critical. In the present work we used six different CTAB (Hexadecyltrimethylammonium bromide) products and one BDAC (Benzyldimethylhexadecylammonium chloride) with varying silver nitrate concentration in the seed-mediated growth of gold nanostructures. We synthesized gold nanorods with varying aspect ratio up to 5.5 with a longitudinal surface plasmon resonance peak from 670 to 950 nm. We obtained excellent rod-shape gold nanostructures witch were reliable and reproducible with our method based on common seed-mediated growth. The synthesized nanostructures were characterized by UV-visible spectroscopy, transmission electron microscopy (TEM) and X-ray diffraction (XRD). Here, we report our method in more detail as a user-friendly guide for the production of gold nanorods and tuning of their aspect ratios.

  17. Switching Plasmons: Gold Nanorod-Copper Chalcogenide Core-Shell Nanoparticle Clusters with Selectable Metal/Semiconductor NIR Plasmon Resonances.

    Science.gov (United States)

    Muhammed, Madathumpady Abubaker Habeeb; Döblinger, Markus; Rodríguez-Fernández, Jessica

    2015-09-16

    Exerting control over the near-infrared (NIR) plasmonic response of nanosized metals and semiconductors can facilitate access to unexplored phenomena and applications. Here we combine electrostatic self-assembly and Cd(2+)/Cu(+) cation exchange to obtain an anisotropic core-shell nanoparticle cluster (NPC) whose optical properties stem from two dissimilar plasmonic materials: a gold nanorod (AuNR) core and a copper selenide (Cu(2-x)Se, x ≥ 0) supraparticle shell. The spectral response of the AuNR@Cu2Se NPCs is governed by the transverse and longitudinal plasmon bands (LPB) of the anisotropic metallic core, since the Cu2Se shell is nonplasmonic. Under aerobic conditions the shell undergoes vacancy doping (x > 0), leading to the plasmon-rich NIR spectrum of the AuNR@Cu(2-x)Se NPCs. For low vacancy doping levels the NIR optical properties of the dually plasmonic NPCs are determined by the LPBs of the semiconductor shell (along its major longitudinal axis) and of the metal core. Conversely, for high vacancy doping levels their NIR optical response is dominated by the two most intense plasmon modes from the shell: the transverse (along the shortest transversal axis) and longitudinal (along the major longitudinal axis) modes. The optical properties of the NPCs can be reversibly switched back to a purely metallic plasmonic character upon reversible conversion of AuNR@Cu(2-x)Se into AuNR@Cu2Se. Such well-defined nanosized colloidal assemblies feature the unique ability of holding an all-metallic, a metallic/semiconductor, or an all-semiconductor plasmonic response in the NIR. Therefore, they can serve as an ideal platform to evaluate the crosstalk between plasmonic metals and plasmonic semiconductors at the nanoscale. Furthermore, their versatility to display plasmon modes in the first, second, or both NIR windows is particularly advantageous for bioapplications, especially considering their strong absorbing and near-field enhancing properties.

  18. Sensitivity of metal nanoparticle surface plasmon resonance to the dielectric environment.

    Science.gov (United States)

    Miller, Molly M; Lazarides, Anne A

    2005-11-24

    Electrodynamic simulations of gold nanoparticle spectra were used to investigate the sensitivity of localized surface plasmon band position to the refractive index, n, of the medium for nanoparticles of various shapes and nanoshells of various structures. Among single-component nanoparticles less than 130 nm in size, sensitivities of dipole resonance positions to bulk refractive index are found to depend only upon the wavelength of the resonance and the dielectric properties of the metal and the medium. Among particle plasmons that peak in the frequency range where the real part of the metal dielectric function varies linearly with wavelength and the imaginary part is small and slowly varying, the sensitivity of the peak wavelength, lambda, to refractive index, n, is found to be a linearly increasing function of lambda, regardless of the structural features of the particle that determine lambda. Quasistatic theory is used to derive an analytical expression for the refractive index sensitivity of small particle plasmon peaks. Through this analysis, the dependence of sensitivity on band position is found to be determined by the wavelength dependence of the real part, epsilon', of the particle dielectric function, and the sensitivity results are found to extend to all particles with resonance conditions of the form, epsilon' = -2chin(2), where chi is a function of geometric parameters and other constants. The sensitivity results observed using accurate computational methods for dipolar plasmon bands of gold nanodisks, nanorods, and hollow nanoshells extend, therefore, to particles of other shapes (such as hexagonal and chopped tetrahedral), composed of other metals, and to higher-order modes. The bulk refractive index sensitivity yielded by the theory serves as an upper bound to sensitivities of nanoparticles on dielectric substrates and sensitivities of nanoparticles to local refractive index changes, such as those associated with biomolecule sensing.

  19. Superradiant amplification of terahertz radiation by plasmons in inverted graphene with a planar distributed Bragg resonator

    Energy Technology Data Exchange (ETDEWEB)

    Polischuk, O. V., E-mail: polischuk.sfire@mail.ru; Popov, V. V., E-mail: popov-slava@yahoo.co.uk [Russian Academy of Sciences, Saratov Branch, Kotel’nikov Institute of Radioengineering and Electronics (Russian Federation); Otsuji, T. [Tohoku University, Research Institute for Electrical Communication (Japan)

    2015-11-15

    It is shown theoretically that stimulated generation of terahertz radiation by plasmons in graphene with a planar distributed Bragg resonator is possible at two different frequencies for each plasmon mode. This behavior may be attributed to the superradiance of the collective plasmon mode, which is associated with superlinear increase in the radiative damping of the plasmons with increase in pumping power. As a result, the curves of the radiative damping and the plasmon gain as a function of the pumping power intersect at two points corresponding to different generation conditions.

  20. Multi-bi- and tri-stability using nonlinear plasmonic Fano resonators

    KAUST Repository

    Amin, Muhammad

    2013-09-01

    A plasmonic Fano resonator embedding Kerr nonlinearity is used to achieve multi-bi- and tri-stability. Fano resonance is obtained by inducing higher-order plasmon modes on metallic surfaces via geometrical symmetry breaking. The presence of the multiple higher order plasmon modes provides the means for producing multi-bi- or tri-stability in the response of the resonator when it is loaded with a material with Kerr nonlinearity. The multi-stability in the response of the proposed resonator enables its use in three-state all optical memory and switching applications. © 2013 IEEE.

  1. Formation and Evolution Mechanism of Plasmon Resonance from Single Ring-Shaped Nanotube to Dimer and Arrays

    Directory of Open Access Journals (Sweden)

    F. Q. Zhou

    2014-01-01

    Full Text Available The formation and evolution mechanisms of plasmon resonance from single Ring-shaped nanotube to dimer and arrays are studied; an attempt has been made to bridge the gap between single-tube, dimer, and array. Results show that resonant modes can be divided into three types: quadrupole, hexapole, and octupole resonance from visible to near infrared region, and each mode maintains relatively stable resonant characteristics, but the optical transmission properties including redshift and blueshift of the modes and band gap are highly tunable by adjusting the number of nanotube and intertube spacing values. The field-interference mechanism has been suggested to explain the physical origin.

  2. Plane wave excitation-detection of non-resonant plasmons along finite-width graphene strips.

    Science.gov (United States)

    Gómez-Díaz, J S; Esquius-Morote, M; Perruisseau-Carrier, J

    2013-10-21

    An approach to couple free-space waves and non-resonant plasmons propagating along graphene strips is proposed based on the periodic modulation of the graphene strip width. The solution is technologically very simple, scalable in frequency, and provides customized coupling angle and intensity. Moreover, the coupling properties can be dynamically controlled at a fixed frequency via the graphene electrical field effect, enabling advanced and flexible plasmon excitation-detection strategies. We combine a previously derived scaling law for graphene strips with leaky-wave theory borrowed from microwaves to achieve rigorous and efficient modeling and design of the structure. In particular we analytically derive its dispersion, predict its coupling efficiency and radiated field structure, and design strip configurations able to fulfill specific coupling requirements. The proposed approach and developed methods are essential to the recent and fundamental problem of the excitation-detection of non-resonant plasmons propagating along a continuous graphene strip, and could pave the way to smart all-graphene sensors and transceivers.

  3. Investigation of plasmon resonance tunneling through subwavelength hole arrays in highly doped conductive ZnO films

    Energy Technology Data Exchange (ETDEWEB)

    Nader, Nima, E-mail: nima.nader@nist.gov; Vangala, Shivashankar [Solid State Scientific Corporation, 12 Simon St., Nashua, New Hampshire 03060 (United States); Air Force Research Laboratory, Sensors Directorate, 2241 Avionics Circle, Wright Patterson AFB, Ohio 45433 (United States); Hendrickson, Joshua R.; Leedy, Kevin D.; Cleary, Justin W. [Air Force Research Laboratory, Sensors Directorate, 2241 Avionics Circle, Wright Patterson AFB, Ohio 45433 (United States); Look, David C. [Air Force Research Laboratory, Sensors Directorate, 2241 Avionics Circle, Wright Patterson AFB, Ohio 45433 (United States); Wyle Laboratories, Inc., 2601 Mission Point Blvd., Suite 300, Dayton, Ohio 45435 (United States); Semiconductor Research Center, Wright State University, Dayton, Ohio 45435 (United States); Guo, Junpeng [Department of Electrical and Computer Engineering, University of Alabama in Huntsville, 301 Sparkman Drive, Huntsville, Alabama 35899 (United States)

    2015-11-07

    Experimental results pertaining to plasmon resonance tunneling through a highly conductive zinc oxide (ZnO) layer with subwavelength hole-arrays is investigated in the mid-infrared regime. Gallium-doped ZnO layers are pulsed-laser deposited on a silicon wafer. The ZnO has metallic optical properties with a bulk plasma frequency of 214 THz, which is equivalent to a free space wavelength of 1.4 μm. Hole arrays with different periods and hole shapes are fabricated via a standard photolithography process. Resonant mode tunneling characteristics are experimentally studied for different incident angles and compared with surface plasmon theoretical calculations and finite-difference time-domain simulations. Transmission peaks, higher than the baseline predicted by diffraction theory, are observed in each of the samples at wavelengths that correspond to the excitation of surface plasmon modes.

  4. Quadrupole lattice resonances in plasmonic crystal excited by cylindrical vector beams

    Science.gov (United States)

    Sakai, Kyosuke; Nomura, Kensuke; Yamamoto, Takeaki; Omura, Tatsuya; Sasaki, Keiji

    2016-10-01

    We report a scheme to exploit low radiative loss plasmonic resonance by combining a dark (subradiant) mode and a lattice resonance. We theoretically demonstrate that such dark-mode lattice resonances in periodic arrays of nanodisks or plasmonic crystals can be excited by vertically incident light beams. We investigate the excitation of lattice resonances in a finite sized, square-lattice plasmonic crystal by two types of cylindrical vector beams and a linearly polarized Gaussian beam. Quadrupole lattice resonances are excited by all three beams, and the largest peak intensity is obtained by using a specific type of cylindrical vector beam. Because of their lower radiative losses with many hotspots, the quadrupole lattice resonances in plasmonic crystal may pave the way for photonic research and applications that require strong light-matter interactions.

  5. A nonlinear plasmonic resonator for three-state all-optical switching

    KAUST Repository

    Amin, Muhammad

    2014-01-01

    A nonlinear plasmonic resonator design is proposed for three-state all-optical switching at frequencies including near infrared and lower red parts of the spectrum. The tri-stable response required for three-state operation is obtained by enhancing nonlinearities of a Kerr medium through multiple (higher order) plasmons excited on resonator\\'s metallic surfaces. Indeed, simulations demonstrate that exploitation of multiple plasmons equips the proposed resonator with a multi-band tri-stable response, which cannot be obtained using existing nonlinear plasmonic devices that make use of single mode Lorentzian resonances. Multi-band three-state optical switching that can be realized using the proposed resonator has potential applications in optical communications and computing. © 2014 Optical Society of America.

  6. Plasmonic Properties of Bimetallic Nanostructures and Their Applications in Hydrogen Sensing and Chemical Reactions

    Science.gov (United States)

    Jiang, Ruibin

    Noble metal nanocrystals have attracted great interest from a wide range of research fields because of their intriguing properties endowed by their localized surface plasmon resonances, which are the collective oscillations of free electrons. Under resonant excitation, metal nanostructures exhibit very large scattering and absorption cross sections and large near-field enhancement. These extraordinary properties can be used in different applications, such as plasmonic sensing and imaging, plasmon-controlled optics, photothermal therapy, photocatalysis, solar cells, and so on. Gold and Silver nanocrystals have plasmon resonances in the visible and near-infrared regions. However, gold and silver are not suitable for some applications. For example, they are generally inactive for catalyzing chemical reactions. The integration of plasmonic metals with other metals can offer superior or new physical/chemical properties. In this thesis, I prepared Au/Ag and Au/Pd bimetallic nanostructures and studied their plasmonic properties and applications in hydrogen sensing and photocatalysis. Seeds have a crucial importance in the synthesis of bimetallic nanostructures. I therefore first studied the roles of the crystalline structure and shape of seeds on the overgrowth of bimetallic nanostructures. The overgrowth of silver and palladium on single crystalline Au nanorods, multicrystalline Au nanorods, and nanobipyramids were studied under the same conditions for each metal. The growths of silver and palladium on single crystalline Au nanorods gave cuboidal nanostructures, while rod-shaped nanostructures were obtained from the growths of silver and palladium on multicrystalline Au nanorods and nanobipyramids. Moreover, the growths of silver and palladium on multicrystalline Au nanobipyramids started at the stepped side facets, while the growths started at the twin boundaries on multicrystalline Au nanorods. These results unambiguously indicate that the crystalline structure of

  7. Tunable plasmon resonance in the nanobars and split ring resonator(SRR) composite structure

    Science.gov (United States)

    Xu, Haiqing; Li, Hongjian; Xiao, Gang; Chen, Qiao

    2016-10-01

    We have proposed a multi-band metamaterials composed of bars and planer SRR. There are three sharp peaks in the transmission spectra in the visible and near-infrared region, we find that the transmission spectra are highly tunable as the coupling and geometric parameters modifying, especially the third peak in the near-infrared region. When the gap distance between the two nanobar g1<14 nm, the original first peak will split, a new dip and peak will exist, which is results from the high-order plasmon resonance. When introducing asymmetry to the planer SRR, a new sharp peak accompany with a new sharp dip exists in the original second peak, which is originated from the strong electric field resonance. We also find that the proposed structures with sensing sensitivity of ~467 nm/RIU, which can be used for plasmonic sensor.

  8. Spectral Tuning of Plasmon Resonance in a Core/Shell (Au)Ag Nanocomposite

    Science.gov (United States)

    Panarin, A. Yu.; Abakshonok, A. V.; Agabekov, V. E.; Eryomin, A. N.; Terekhov, S. N.

    2015-01-01

    A bimetallic (Au)Ag nanocomposite with a core/shell structure was synthesized in aqueous solution and a H2O/EtOH mixture (1:1) containing polymers (carboxymethylcellulose, sodium polystyrenesulfonate, polyvinylpyrrolidone, dextran). Its structure and optical properties were characterized. The shape and position of scattering bands of colloidal noble-metal nanoparticles with optical density <0.1 were undistorted by solvent absorption. Scattering spectra had to be corrected for solutions of greater optical density. A method for correcting the resonant lightscattering spectra of Au and (Au)Ag nanoparticles was proposed for a single-beam apparatus. The possibility of surface plasmon resonance tuning for (Au)Ag with a short-wavelength shift of ~150 nm for the absorption band maximum and of ~84 nm for the resonant scattering band was demonstrated by varying the AgNO3 concentration during formation of the silver shell on the gold core.

  9. Aluminum for nonlinear plasmonics: resonance-driven polarized luminescence of Al, Ag, and Au nanoantennas.

    Science.gov (United States)

    Castro-Lopez, Marta; Brinks, Daan; Sapienza, Riccardo; van Hulst, Niek F

    2011-11-09

    Resonant optical antennas are ideal for nanoscale nonlinear optical interactions due to their inherent strong local field enhancement. Indeed second- and third-order nonlinear response of gold nanoparticles has been reported. Here we compare the on- and off-resonance properties of aluminum, silver, and gold nanoantennas, by measuring two-photon photoluminescence. Remarkably, aluminum shows 2 orders of magnitude higher luminescence efficiency than silver or gold. Moreover, in striking contrast to gold, the aluminum emission largely preserves the linear incident polarization. Finally, we show the systematic resonance control of two-photon excitation and luminescence polarization by tuning the antenna width and length independently. Our findings point to aluminum as a promising metal for nonlinear plasmonics.

  10. Numerical analysis of surface plasmon resonance effects on a rotational silver nanorod/nanoshell dimer

    Science.gov (United States)

    Chou Chau, Yuan-Fong

    2013-06-01

    In this work, we numerically investigate the surface plasmon resonance (SPR) effects on a pair of rotational silver nanorod/nanoshell dimer with a finite height of 1000 nm by means of finite element method with three dimensional calculation. The rotational angles of the silver nanorod/nanoshell dimer are chosen θ=0°, θ=25°, θ=45° and θ=90°, respectively. The proposed structure exhibits a red-shifted localized SPR that can tuned over an extended wavelength range by varying the dielectric constant in metal nanoshell and the rotational angle of the silver nanorod/nanoshell dimer. The tunable optical properties on SPR phenomena are attributed to the rotational effect and a larger effective size of dielectric constant that is filled with a higher refractive medium of finite height of metal nanorod/nanoshell. This unique property of a pair of rotational nanorod/nanoshell dimer is highly attractive for serving as resonant center to hold and probe smaller nanostructures, such as biomolecules or quantum dots. Such structures also show significant promise for applications in nano-switch devices, sensing, and surface-enhanced spectroscopy, due to their strong and tunable plasmon resonances.

  11. Hollow Au/Ag nanostars displaying broad plasmonic resonance and high surface-enhanced Raman sensitivity

    Science.gov (United States)

    Garcia-Leis, Adianez; Torreggiani, Armida; Garcia-Ramos, Jose Vicente; Sanchez-Cortes, Santiago

    2015-08-01

    Bimetallic Au/Ag hollow nanostar (HNS) nanoparticles with different morphologies were prepared in this work. These nanoplatforms were obtained by changing the experimental conditions (concentration of silver and chemical reductors, hydroxylamine and citrate) and by using Ag nanostars as template nanoparticles (NPs) through galvanic replacement. The goal of this research was to create bimetallic Au/Ag star-shaped nanoparticles with advanced properties displaying a broader plasmonic resonance, a cleaner exposed surface, and a high concentration of electromagnetic hot spots on the surface provided by the special morphology of nanostars. The size, shape, and composition of Ag as well as their optical properties were studied by extinction spectroscopy, hyperspectral dark field microscopy, transmission and scanning electron microscopy (TEM and SEM), and energy dispersive X-ray spectroscopy (EDX). Finally, the surface-enhanced Raman scattering (SERS) activity of these HNS was investigated by using thioflavin T, a biomarker of the β-amyloid fibril formation, responsible for Alzheimer's disease. Lucigenin, a molecule displaying different SERS activities on Au and Ag, was also used to explore the presence of these metals on the NP surface. Thus, a relationship between the morphology, plasmon resonance and SERS activity of these new NPs was made.Bimetallic Au/Ag hollow nanostar (HNS) nanoparticles with different morphologies were prepared in this work. These nanoplatforms were obtained by changing the experimental conditions (concentration of silver and chemical reductors, hydroxylamine and citrate) and by using Ag nanostars as template nanoparticles (NPs) through galvanic replacement. The goal of this research was to create bimetallic Au/Ag star-shaped nanoparticles with advanced properties displaying a broader plasmonic resonance, a cleaner exposed surface, and a high concentration of electromagnetic hot spots on the surface provided by the special morphology of nanostars

  12. Atomically precise gold nanocrystal molecules with surface plasmon resonance.

    Science.gov (United States)

    Qian, Huifeng; Zhu, Yan; Jin, Rongchao

    2012-01-17

    Since Faraday's pioneering work on gold colloids, tremendous scientific research on plasmonic gold nanoparticles has been carried out, but no atomically precise Au nanocrystals have been achieved. This work reports the first example of gold nanocrystal molecules. Mass spectrometry analysis has determined its formula to be Au(333)(SR)(79) (R = CH(2)CH(2)Ph). This magic sized nanocrystal molecule exhibits fcc-crystallinity and surface plasmon resonance at approximately 520 nm, hence, a metallic nanomolecule. Simulations have revealed that atomic shell closing largely contributes to the particular robustness of Au(333)(SR)(79), albeit the number of free electrons (i.e., 333 - 79 = 254) is also consistent with electron shell closing based on calculations using a confined free electron model. Guided by the atomic shell closing growth mode, we have also found the next larger size of extraordinarily stability to be Au(~530)(SR)(~100) after a size-focusing selection--which selects the robust size available in the starting polydisperse nanoparticles. This work clearly demonstrates that atomically precise nanocrystal molecules are achievable and that the factor of atomic shell closing contributes to their extraordinary stability compared to other sizes. Overall, this work opens up new opportunities for investigating many fundamental issues of nanocrystals, such as the formation of metallic state, and will have potential impact on condensed matter physics, nanochemistry, and catalysis as well.

  13. Enhancing Surface Plasmon Resonance Detection Using Nanostructured Au Chips

    Science.gov (United States)

    Indutnyi, Ivan; Ushenin, Yuriy; Hegemann, Dirk; Vandenbossche, Marianne; Myn'ko, Victor; Lukaniuk, Mariia; Shepeliavyi, Petro; Korchovyi, Andrii; Khrystosenko, Roman

    2016-12-01

    The increase of the sensitivity of surface plasmon resonance (SPR) refractometers was studied experimentally by forming a periodic relief in the form of a grating with submicron period on the surface of the Au-coated chip. Periodic reliefs of different depths and spatial frequency were formed on the Au film surface using interference lithography and vacuum chalcogenide photoresists. Spatial frequencies of the grating were selected close to the conditions of Bragg reflection of plasmons for the working wavelength of the SPR refractometer and the used environment (solution of glycerol in water). It was found that the degree of refractometer sensitivity enhancement and the value of the interval of environment refractive index variation, Δ n, in which this enhancement is observed, depend on the depth of the grating relief. By increasing the depth of relief from 13.5 ± 2 nm to 21.0 ± 2 nm, Δ n decreased from 0.009 to 0.0031, whereas sensitivity increased from 110 deg./RIU (refractive index unit) for a standard chip up to 264 and 484 deg./RIU for the nanostructured chips, respectively. Finally, it was shown that the working range of the sensor can be adjusted to the refractive index of the studied environment by changing the spatial frequency of the grating, by modification of the chip surface or by rotation of the chip.

  14. Hybridized plasmon resonant modes in molecular metallodielectric quad-triangles nanoantenna

    Science.gov (United States)

    Ahmadivand, Arash; Sinha, Raju; Pala, Nezih

    2015-11-01

    In this study, we examined the plasmon response for both metallic and metallodielectric nanoantennas composed of four gold (Au) triangles in a quadrumer orientation. Tailoring an artificial metallic quad-triangles nanoantenna, it is shown that the structure is able to support pronounced plasmon and Fano resonances in the visible spectrum. Using plasmon transmutation effect, we showed that the plasmonic response of the proposed cluster can be enhanced with the placement of carbon nanoparticles in the offset gaps between the proximal triangles. It is verified that this structural modification gives rise to formation of new collective magnetic antibonding (dark) plasmon modes. Excitation of these subradiant dark modes leads to formation of narrower and deeper Fano resonances in the spectral response of the metallodielectric nanoantenna. To investigate the practical applications of the metallodielectric structure, we immersed the nano-assembly in various liquids with different refractive indices to define its sensitivity to the environmental perturbation as a plasmonic biological sensor.

  15. Surface plasmon resonance spectroscopy of single bowtie nano-antennas using a differential reflectivity method.

    Science.gov (United States)

    Kaniber, M; Schraml, K; Regler, A; Bartl, J; Glashagen, G; Flassig, F; Wierzbowski, J; Finley, J J

    2016-03-23

    We report on the structural and optical properties of individual bowtie nanoantennas both on glass and semiconducting GaAs substrates. The antennas on glass (GaAs) are shown to be of excellent quality and high uniformity reflected by narrow size distributions with standard deviations for the triangle and gap size of = 4.5 nm = 2.6 nm and = 5.4 nm = 3.8 nm, respectively. The corresponding optical properties of individual nanoantennas studied by differential reflection spectroscopy show a strong reduction of the localised surface plasmon polariton resonance linewidth from 0.21 eV to 0.07 eV upon reducing the antenna size from 150 nm to 100 nm. This is attributed to the absence of inhomogeneous broadening as compared to optical measurements on nanoantenna ensembles. The inter-particle coupling of an individual bowtie nanoantenna, which gives rise to strongly localised and enhanced electromagnetic hotspots, is demonstrated using polarization-resolved spectroscopy, yielding a large degree of linear polarization of ρmax ~ 80%. The combination of highly reproducible nanofabrication and fast, non-destructive and non-contaminating optical spectroscopy paves the route towards future semiconductor-based nano-plasmonic circuits, consisting of multiple photonic and plasmonic entities.

  16. Calibration of Surface Plasmon Resonance Imager for Biochemical Detection

    Directory of Open Access Journals (Sweden)

    T. Ktari

    2012-01-01

    Full Text Available We present a new Surface Plasmon Resonance imager (SPRi based on immobilized T4-phage for bacteria detection. First, we present the sensitivity of the SPR imager towards refractive index variation for biosensor application. The SPR imager can be calibrated versus different percentage of triethylene glycol mixture in ultrapure water. The system can be used as a refractometer with sensitivity below 5×10−5 in the range of 1.33300–1.34360. Second, bacteriophage (T4-phage can be physisorbed on gold microarray spots for bacteria detection. The kinetic physisorption of different concentrations of T4-phages can be observed in real time. Finally, two types of bacteria such as E. coli (gram negative and Lactobacillus (gram positive were used for positive and negative tests. The results show a selectivity of T4-phage toward E. coli with a detection limit below 104 CFU/mL and with good reproducibility.

  17. Surface Plasmon Resonance for Cell-Based Clinical Diagnosis

    Directory of Open Access Journals (Sweden)

    Yuhki Yanase

    2014-03-01

    Full Text Available Non-invasive real-time observations and the evaluation of living cell conditions and functions are increasingly demanded in life sciences. Surface plasmon resonance (SPR sensors detect the refractive index (RI changes on the surface of sensor chips in label-free and on a real-time basis. Using SPR sensors, we and other groups have developed techniques to evaluate living cells’ reactions in response to stimuli without any labeling in a real-time manner. The SPR imaging (SPRI system for living cells may visualize single cell reactions and has the potential to expand application of SPR cell sensing for clinical diagnosis, such as multi-array cell diagnostic systems and detection of malignant cells among normal cells in combination with rapid cell isolation techniques.

  18. Optofluidic cellular immunofunctional analysis by localized surface plasmon resonance

    Science.gov (United States)

    Kurabayashi, Katsuo; Oh, Bo-Ram

    2014-08-01

    Cytokine secretion assays provide the means to quantify intercellular-signaling proteins secreted by blood immune cells. These assays allow researchers and clinicians to obtain valuable information on the immune status of the donor. Previous studies have demonstrated that localized surface plasmon resonance (LSPR) effects enable label-free, real-time biosensing on a nanostructured metallic surface with simple optics and sensing tunability. However, limited sensitivity coupled with a lack of sample handling capability makes it challenging to implement LSPR biosensing in cellular functional immunoanalysis based on cytokine secretion assay. This paper describes our recent progress towards full development of a label-free LSPR biosensing technique to detect cell-secreted tumor necrosis factor (TNF)-α cytokines in clinical blood samples. We integrate LSPR bionanosensors in an optofluidic platform capable of handling target immune cells in a microfluidic chamber while readily permitting optical access for cytokine detection.

  19. Noninvasive and Real-Time Plasmon Waveguide Resonance Thermometry

    Directory of Open Access Journals (Sweden)

    Pengfei Zhang

    2015-04-01

    Full Text Available In this paper, the noninvasive and real-time plasmon waveguide resonance (PWR thermometry is reported theoretically and demonstrated experimentally. Owing to the enhanced evanescent field and thermal shield effect of its dielectric layer, a PWR thermometer permits accurate temperature sensing and has a wide dynamic range. A temperature measurement sensitivity of 9.4 × 10−3 °C is achieved and the thermo optic coefficient nonlinearity is measured in the experiment. The measurement of water cooling processes distributed in one dimension reveals that a PWR thermometer allows real-time temperature sensing and has potential to be applied for thermal gradient analysis. Apart from this, the PWR thermometer has the advantages of low cost and simple structure, since our transduction scheme can be constructed with conventional optical components and commercial coating techniques.

  20. Polarization switching from plasmonic lattice mode to multipolar localized surface plasmon resonances in arrays of large nanoantennas

    Science.gov (United States)

    Wing, Waylin J.; Sadeghi, Seyed M.; Gutha, Rithvik R.

    2016-12-01

    We experimentally investigate plasmonic lattice modes of gold nanoantenna arrays that occur in asymmetric structures containing a silica substrate and either air or a thin layer of a high-index dielectric. Very distinct polarization switching is observed in the nanoantenna arrays wherein by rotating the incident light polarization by ninety degrees, the array can exhibit either a plasmonic lattice mode or a multipolar localized surface plasmon resonance of varying nature. A large range of nanoantenna lengths are studied, and since the length of the nanoantennas dictates the multipolar localized surface plasmon resonance, we find that the characteristics of the polarization switching are affected accordingly. We also investigate how the thin layer of the high-index dielectric on top of the nanoantenna arrays, in conjunction with varying nanoantenna length, impacts the generation of plasmonic lattice modes and the polarization switching in the arrays. The high-index dielectric is found to assist in the generation and optical coupling of the plasmonic lattice modes. By altering the angle of incidence, the polarization switching can become very large, and the arrays can be made to selectively transmit light of certain wavelengths.

  1. Optical properties of a nanomatch-like plasmonic structure.

    Science.gov (United States)

    Cui, Xudong; Zhang, Weihua; Erni, Daniel; Dong, Lixin

    2010-08-01

    The optical properties of a match-like plasmonic nanostructure are numerically investigated using full-wave finite-difference time-domain analysis in conjunction with dispersive material models. This work is mainly motivated by the developed technique enabling reproducible fabrication of nanomatch structures as well as the growing applications that utilize the localized field enhancement in plasmonic nanostructures. Our research revealed that due to the pronounced field enhancement and larger resonance tunabilities, some nanomatch topologies show potentials for various applications in the field of, e.g., sensing as well as a novel scheme for highly reproducible tips in scanning near field optical microscopy, among others. Despite the additional degrees of freedom that are offered by the composite nature of the proposed nanomatch topology, the paper also reflects on a fundamental complication intrinsic to the material interfaces especially in the nanoscale: stoichiometric mixing. We conclude that the specificity in material modeling will become a significant issue in future research on functionalized composite nanostructures.

  2. Microcontact imprinted surface plasmon resonance sensor for myoglobin detection

    Energy Technology Data Exchange (ETDEWEB)

    Osman, Bilgen [Uludag University, Department of Chemistry, Bursa (Turkey); Uzun, Lokman [Hacettepe University, Department of Chemistry, Ankara (Turkey); Beşirli, Necati [Uludag University, Department of Chemistry, Bursa (Turkey); Denizli, Adil, E-mail: denizli@hacettepe.edu.tr [Hacettepe University, Department of Chemistry, Ankara (Turkey)

    2013-10-15

    In this study, we prepared surface plasmon resonance (SPR) sensor using the molecular imprinting technique for myoglobin detection in human serum. For this purpose, we synthesized myoglobin imprinted poly(hydroxyethyl methacrylate-N-methacryloyl-L-tryptophan methyl ester) [poly(HEMA-MATrp)] nanofilm on the surface of SPR sensor. We also synthesized non-imprinted poly(HEMA-MATrp) nanofilm without myoglobin for the control experiments. The SPR sensor was characterized with contact angle measurements, atomic force microscopy, X-ray photoelectron spectroscopy, and ellipsometry. We investigated the effectiveness of the sensor using the SPR system. We evaluated the ability of SPR sensor to sense myoglobin with myoglobin solutions (pH 7.4, phosphate buffer) in different concentration range and in the serum taken from a patient with acute myocardial infarction. We found that the Langmuir adsorption model was the most suitable for the sensor system. The detection limit was 87.6 ng/mL. In order to show the selectivity of the SPR sensor, we investigated the competitive detection of myoglobin, lysozyme, cytochrome c and bovine serum albumin. The results showed that the SPR sensor has high selectivity and sensitivity for myoglobin. - Highlights: • Micro-contact imprinted surface plasmon resonance sensor. • Real-time myoglobin detection in the serum taken from a patient with acute myocardial infarction • Reproducible results for consecutive myoglobin solution supplement • LOD and LOQ values of the SPR sensor were determined to be 26.3 and 87.6 ng/mL. • The SPR sensor has potential for myoglobin sensing during acute MI cases.

  3. Raman scattering enhancement in photon-plasmon resonance mediated metal-dielectric microcavity

    Science.gov (United States)

    Guddala, Sriram; Dwivedi, Vindesh K.; Vijaya Prakash, G.; Narayana Rao, D.

    2013-12-01

    Here, we report the photon-plasmon interaction scheme and enhanced field strengths resulted into the amplification of phonon in a novel microcavity. A metal-dielectric microcavity, with unified cavity photonic mode and localized surface plasmon resonances, is visualized by impregnating the gold nanoparticles into the deep see-through nano-sized pores of porous silicon microcavity. The intense optical field strengths resulting from the photon-plasmon interactions are probed by both resonant and non-resonant Raman scattering experiments. Due to photon-plasmon-phonon interaction mechanism, several orders of enhancement in the intensity of scattered Raman Stokes photon (at 500 cm-1) are observed. Our metal nanoparticle-microcavity hybrid system shows the potential to improve the sensing figure of merit as well as the applications of plasmonics for optoelectronics, photovoltaics, and related technologies.

  4. Raman scattering enhancement in photon-plasmon resonance mediated metal-dielectric microcavity

    Energy Technology Data Exchange (ETDEWEB)

    Guddala, Sriram; Narayana Rao, D., E-mail: dnr.laserlab@gmail.com, E-mail: dnrsp@uohyd.ernet.in [School of Physics, University of Hyderabad, Hyderabad 500 046 (India); Dwivedi, Vindesh K.; Vijaya Prakash, G. [Nanophotonics Laboratory, Department of Physics, IIT Delhi, New Delhi 110 016 (India)

    2013-12-14

    Here, we report the photon-plasmon interaction scheme and enhanced field strengths resulted into the amplification of phonon in a novel microcavity. A metal-dielectric microcavity, with unified cavity photonic mode and localized surface plasmon resonances, is visualized by impregnating the gold nanoparticles into the deep see-through nano-sized pores of porous silicon microcavity. The intense optical field strengths resulting from the photon-plasmon interactions are probed by both resonant and non-resonant Raman scattering experiments. Due to photon-plasmon-phonon interaction mechanism, several orders of enhancement in the intensity of scattered Raman Stokes photon (at 500 cm{sup −1}) are observed. Our metal nanoparticle-microcavity hybrid system shows the potential to improve the sensing figure of merit as well as the applications of plasmonics for optoelectronics, photovoltaics, and related technologies.

  5. Plasmon resonances in a stacked pair of graphene ribbon arrays with a lateral displacement.

    Science.gov (United States)

    He, Meng-Dong; Zhang, Gui; Liu, Jian-Qiang; Li, Jian-Bo; Wang, Xin-Jun; Huang, Zhen-Rong; Wang, Lingling; Chen, Xiaoshuang

    2014-03-24

    We find that a stacked pair of graphene ribbon arrays with a lateral displacement can excite plasmon waveguide mode in the gap between ribbons, as well as surface plasmon mode on graphene ribbon surface. When the resonance wavelengthes of plasmon waveguide mode and surface plasmon mode are close to each other, there is a strong electromagnetic interaction between the two modes, and then they contribute together to transmission dip. The plasmon waveguide mode resonance can be manipulated by the lateral displacement and longitudinal interval between arrays due to their influence on the manner and strength of electromagnetic coupling between two arrays. The findings expand our understanding of electromagnetic resonances in graphene-ribbon array structure and may affect further engineering of nanoplasmonic devices and metamaterials.

  6. Theory and Applications of Surface Plasmon Resonance, Resonant Mirror, Resonant Waveguide Grating, and Dual Polarization Interferometry Biosensors

    Directory of Open Access Journals (Sweden)

    Billy W. Day

    2010-11-01

    Full Text Available Biosensors have been used extensively in the scientific community for several purposes, most notably to determine association and dissociation kinetics, protein-ligand, protein-protein, or nucleic acid hybridization interactions. A number of different types of biosensors are available in the field, each with real or perceived benefits over the others. This review discusses the basic theory and operational arrangements of four commercially available types of optical biosensors: surface plasmon resonance, resonant mirror, resonance waveguide grating, and dual polarization interferometry. The different applications these techniques offer are discussed from experiments and results reported in recently published literature. Additionally, recent advancements or modifications to the current techniques are also discussed.

  7. A selectively coated photonic crystal fiber based surface plasmon resonance sensor

    DEFF Research Database (Denmark)

    Yu, X; Zhang, Y.; Pan, S.S.

    2010-01-01

    We propose a novel design for a photonic crystal fiber based surface plasmonic resonance sensor. The sensor consists of selectively metal-coated air holes containing analyte channels, which enhance the phase matching between the plasmonic mode and the core-guided mode. Good refractive index sensi...

  8. Electron photoemission in plasmonic nanoparticle arrays: analysis of collective resonances and embedding effects

    DEFF Research Database (Denmark)

    Zhukovsky, Sergei V.; Babicheva, Viktoriia; Uskov, Alexander

    2014-01-01

    effects in the formation of plasmonic resonance is diminished. We also show that 5-20 times increase of photoemission can be achieved on embedding of nanoparticles without taking into account dynamics of ballistic electrons. The results obtained can be used to increase efficiency of plasmon...

  9. Spoof Plasmon Hybridization

    CERN Document Server

    Zhang, Jingjing; Luo, Yu; Shen, Xiaopeng; Maier, Stefan A; Cui, Tie Jun

    2016-01-01

    Plasmon hybridization between closely spaced nanoparticles yields new hybrid modes not found in individual constituents, allowing for the engineering of resonance properties and field enhancement capabilities of metallic nanostructure. Experimental verifications of plasmon hybridization have been thus far mostly limited to optical frequencies, as metals cannot support surface plasmons at longer wavelengths. Here, we introduce the concept of 'spoof plasmon hybridization' in highly conductive metal structures and investigate experimentally the interaction of localized surface plasmon resonances (LSPR) in adjacent metal disks corrugated with subwavelength spiral patterns. We show that the hybridization results in the splitting of spoof plasmon modes into bonding and antibonding resonances analogous to molecular orbital rule and plasmonic hybridization in optical spectrum. These hybrid modes can be manipulated to produce enormous field enhancements (larger than 5000) by tuning the separation between disks or alte...

  10. Ultra-sharp plasmonic resonances from monopole optical nanoantenna phased arrays

    Energy Technology Data Exchange (ETDEWEB)

    Li, Shi-Qiang; Bruce Buchholz, D. [Department of Materials Science and Engineering, Northwestern University, 2220 Campus Dr., Evanston, Illinois 60208-3108 (United States); Zhou, Wei [Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford St., Cambridge, Massachusetts 02138 (United States); Ketterson, John B. [Department of Physics, Northwestern University, 2145 Sheridan Rd., Evanston, Illinois 60208-3113 (United States); NU-NIMS Materials Innovation Center, 2220 Campus Dr., Evanston, Illinois 60208-3108 (United States); Ocola, Leonidas E. [Center for Nanoscale Materials, Argonne National Laboratory, 9700 S Cass Ave., Lemont, Illinois 60439 (United States); Sakoda, Kazuaki [NU-NIMS Materials Innovation Center, 2220 Campus Dr., Evanston, Illinois 60208-3108 (United States); National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Chang, Robert P. H., E-mail: r-chang@northwestern.edu [Department of Materials Science and Engineering, Northwestern University, 2220 Campus Dr., Evanston, Illinois 60208-3108 (United States); NU-NIMS Materials Innovation Center, 2220 Campus Dr., Evanston, Illinois 60208-3108 (United States)

    2014-06-09

    Diffractively coupled plasmonic resonances possess both ultra-sharp linewidths and giant electric field enhancement around plasmonic nanostructures. They can be applied to create a new generation of sensors, detectors, and nano-optical devices. However, all current designs require stringent index-matching at the resonance condition that limits their applicability. Here, we propose and demonstrate that it is possible to relieve the index-matching requirement and to induce ultra-sharp plasmon resonances in an ordered vertically aligned optical nano-antenna phased array by transforming a dipole resonance to a monopole resonance with a mirror plane. Due to the mirror image effect, the monopole resonance not only retained the dipole features but also enhanced them. The engineered resonances strongly suppressed the radiative decay channel, resulting in a four-order of magnitude enhancement in local electric field and a Q-factor greater than 200.

  11. Colloidal Plasmonic Titanium Nitride Nanoparticles: Properties and Applications

    DEFF Research Database (Denmark)

    Guler, Urcan; Suslov, Sergey; Kildishev, Alexander V.

    2015-01-01

    Optical properties of colloidal plasmonic titanium nitride nanoparticles are examined with an eye on their photothermal and photocatalytic applications via transmission electron microscopy and optical transmittance measurements. Single crystal titanium nitride cubic nanoparticles with an average...

  12. Refractive index dispersion of swift heavy ion irradiated BFO thin films using Surface Plasmon Resonance technique

    Energy Technology Data Exchange (ETDEWEB)

    Paliwal, Ayushi [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Sharma, Savita [Department of Applied Physics, Delhi Technological University, Delhi (India); Tomar, Monika [Physics Department, Miranda House, University of Delhi, Delhi 110007 (India); Singh, Fouran [Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110075 (India); Gupta, Vinay, E-mail: drguptavinay@gmail.com [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India)

    2016-07-15

    Highlights: • Investigated the optical properties of BiFeO{sub 3} (BFO) thin films after irradiation using SPR. • Otto configuration has been used to excite the surface plasmons using gold metal thin film. • BFO thin films were prepared by sol–gel spin coating technique. • Examined the refractive index dispersion of pristine and irradiated BFO thin film. - Abstract: Swift heavy ion irradiation (SHI) is an effective technique to induce defects for possible modifications in the material properties. There is growing interest in studying the optical properties of multiferroic BiFeO{sub 3} (BFO) thin films for optoelectronic applications. In the present work, BFO thin films were prepared by sol–gel spin coating technique and were irradiated using the 15 UD Pelletron accelerator with 100 MeV Au{sup 9+} ions at a fluence of 1 × 10{sup 12} ions cm{sup −2}. The as-grown films became rough and porous on ion irradiation. Surface Plasmon Resonance (SPR) technique has been identified as a highly sensitive and powerful technique for studying the optical properties of a dielectric material. Optical properties of BFO thin films, before and after irradiation were studied using SPR technique in Otto configuration. Refractive index is found to be decreasing from 2.27 to 2.14 on ion irradiation at a wavelength of 633 nm. Refractive index dispersion of BFO thin film (from 405 nm to 633 nm) before and after ion radiation was examined.

  13. Electron energy-loss spectroscopy of branched gap plasmon resonators

    DEFF Research Database (Denmark)

    Raza, Søren; Esfandyarpour, Majid; Koh, Ai Leen

    2016-01-01

    The miniaturization of integrated optical circuits below the diffraction limit for high-speed manipulation of information is one of the cornerstones in plasmonics research. By coupling to surface plasmons supported on nanostructured metallic surfaces, light can be confined to the nanoscale...... microscope combined with electron energy-loss spectroscopy, we experimentally show the propagation, bending and splitting of slot gap plasmons....

  14. Active control of surface plasmon resonance in MoS2-Ag hybrid nanostructures

    CERN Document Server

    Zu, Shuai; Gong, Yongji; Ajayan, Pulickel M; Fang, Zheyu

    2016-01-01

    Molybdenum disulfide (MoS2) monolayers have attracted much attention for their novel optical properties and efficient light-matter interactions. When excited by incident laser, the optical response of MoS2 monolayers was effectively modified by elementary photo-excited excitons owing to their large exciton binding energy, which can be facilitated for the optical-controllable exciton-plasmon interactions. Inspired by this concept, we experimentally investigated active light control of surface plasmon resonance (SPR) in MoS2-Ag hybrid nanostructures. The white light spectra of SPR were gradually red-shifted by increasing laser power, which was distinctly different from the one of bare Ag nanostructure. This spectroscopic tunability can be further controlled by near-field coupling strength and polarization state of light, and selectively applied to the control of plasmonic dark mode. An analytical Lorentz model for photo-excited excitons induced modulation of MoS2 dielectric function was developed to explain the...

  15. Coil-type Fano Resonances: a Plasmonic Approach to Magnetic Sub-diffraction Confinement

    KAUST Repository

    Panaro, Simone

    2015-05-10

    Matrices of nanodisk trimers are introduced as plasmonic platforms for the generation of localized magnetic hot-spots. In Fano resonance condition, the optical magnetic fields can be squeezed in sub-wavelength regions, opening promising scenarios for spintronics.

  16. Influence of nanoparticle-graphene separation on the localized surface plasmon resonances of metal nanoparticles

    CERN Document Server

    Saadabad, Reza Masoudian; Shirdel-Havar, Amir Hushang; Havar, Majid Shirdel

    2015-01-01

    We develop a theory to model the interaction of graphene substrate with localized plasmon resonances in metallic nanoparticles. The influence of a graphene substrate on the surface plasmon resonances is described using an effective background permittivity that is derived from a pseudoparticle concept using the electrostatic method. For this purpose, the interaction of metal nanoparticle with graphene sheet is studied to obtain the optical spectrum of gold nanoparticles deposited on a graphene substrate. Then, we introduce a factor based on dipole approximation to predict the influence of the separation of nanoparticles and graphene on the spectral position of the localized plasmon resonance of the nanoparticles. We applied the theory for a 4 nm radius gold nanosphere placed near 1.5 nm graphene layer. It is shown that a blue shift is emerged in the position of plasmon resonance when the nanoparticle moves away from graphene.

  17. Optical Properties and Plasmonic Performance of Titanium Nitride

    Directory of Open Access Journals (Sweden)

    Panos Patsalas

    2015-05-01

    Full Text Available Titanium nitride (TiN is one of the most well-established engineering materials nowadays. TiN can overcome most of the drawbacks of palsmonic metals due to its high electron conductivity and mobility, high melting point and due to the compatibility of its growth with Complementary Metal Oxide Semiconductor (CMOS technology. In this work, we review the dielectric function spectra of TiN and we evaluate the plasmonic performance of TiN by calculating (i the Surface Plasmon Polariton (SPP dispersion relations and (ii the Localized Surface Plasmon Resonance (LSPR band of TiN nanoparticles, and we demonstrate a significant plasmonic performance of TiN.

  18. Highly sensitive surface plasmon resonance chemical sensor based on Goos-Hanchen effects

    Science.gov (United States)

    Yin, Xiaobo; Hesselink, Lambertus

    2006-08-01

    The resonance enhanced Goos-Hanchen shifts at attenuated total internal reflection enables the possibility for highly sensitive surface plasmon resonance sensor. The observed giant displacements result from the singular phase retardation at the resonance where the phase is continuous but changes dramatically. The phenomenon is proposed for chemical sensing and the superior sensitivity is demonstrated.

  19. Role of multipolar plasmon resonances during surface-enhanced Raman spectroscopy on Au micro-patches

    DEFF Research Database (Denmark)

    Dowd, Annette; Geisler, Mathias; Zhu, Shaoli;

    2016-01-01

    The enhancement of a Raman signal by multipolar plasmon resonances – as opposed to the more common practice of using dipolar resonances – is investigated. A wide range of gold stars, triangles, circles and squares with multipolar resonances in the visible region were designed and then produced...

  20. Detuned-resonator induced transparency in dielectric-loaded plasmonic waveguides

    DEFF Research Database (Denmark)

    Han, Zhanghua; García Ortíz, César Eduardo; Radko, Ilya P.;

    2013-01-01

    We report on the experimental demonstration of detuned-resonator induced transparency in the near-infrared (∼800  nm) using two detuned racetrack resonators side-coupled to a bus waveguide. Both resonators and the bus waveguide are in the form of dielectric-loaded surface plasmon polariton...

  1. Tailoring surface plasmon resonance and dipole cavity plasmon modes of scattering cross section spectra on the single solid-gold/gold-shell nanorod

    Energy Technology Data Exchange (ETDEWEB)

    Chou Chau, Yuan-Fong, E-mail: chou.fong@ubd.edu.bn; Lim, Chee Ming; Kumara, N. T. R. N.; Yoong, Voo Nyuk [Centre for Advanced Material and Energy Sciences, Universiti Brunei Darussalam, Tungku Link, Gadong BE1410, Brunei (Brunei Darussalam); Lee, Chuanyo [Department of Electronic Engineering, Chien Hsin University of Science and Technology, No. 229, Jianxing Rd., Zhongli City, Taoyuan County 32097, Taiwan (China); Huang, Hung Ji; Lin, Chun-Ting [Instrument Technology Research Center, National Applied Research Laboratories, Hsinchu, Taiwan (China); Chiang, Hai-Pang [Institute of Optoelectronic Sciences, National Taiwan Ocean University, Keelung 202, Taiwan (China)

    2016-09-07

    Tunable surface plasmon resonance (SPR) and dipole cavity plasmon modes of the scattering cross section (SCS) spectra on the single solid-gold/gold-shell nanorod have been numerically investigated by using the finite element method. Various effects, such as the influence of SCS spectra under x- and y-polarizations on the surface of the single solid-gold/gold-shell nanorod, are discussed in detail. With the single gold-shell nanorod, one can independently tune the relative SCS spectrum width by controlling the rod length and rod diameter, and the surface scattering by varying the shell thickness and polarization direction, as well as the dipole peak energy. These behaviors are consistent with the properties of localized SPRs and offer a way to optically control and produce selected emission wavelengths from the single solid-gold/gold-shell nanorod. The electric field and magnetic distributions provide us a qualitative idea of the geometrical properties of the single solid-gold/gold-shell nanorod on plasmon resonance.

  2. Integrated optical gyroscope using active long-range surface plasmon-polariton waveguide resonator.

    Science.gov (United States)

    Zhang, Tong; Qian, Guang; Wang, Yang-Yang; Xue, Xiao-Jun; Shan, Feng; Li, Ruo-Zhou; Wu, Jing-Yuan; Zhang, Xiao-Yang

    2014-01-24

    Optical gyroscopes with high sensitivity are important rotation sensors for inertial navigation systems. Here, we present the concept of integrated resonant optical gyroscope constructed by active long-range surface plasmon-polariton (LRSPP) waveguide resonator. In this gyroscope, LRSPP waveguide doped gain medium is pumped to compensate the propagation loss, which has lower pump noise than that of conventional optical waveguide. Peculiar properties of single-polarization of LRSPP waveguide have been found to significantly reduce the polarization error. The metal layer of LRSPP waveguide is electro-optical multiplexed for suppression of reciprocal noises. It shows a limited sensitivity of ~10(-4) deg/h, and a maximum zero drift which is 4 orders of magnitude lower than that constructed by conventional single-mode waveguide.

  3. Realizing of plasmon Fano resonance with a metal nanowall moving along MIM waveguide

    Science.gov (United States)

    Chen, Fang; Yao, Duanzheng

    2016-06-01

    A larger number of complicated plasmonic nanostructures have been realized to exhibit Fano interference. In this paper, we demonstrate a simple nanostructure, side coupled waveguide resonator system with a metal nanowall located in the metal-insulator-metal waveguide (MIM), which can also achieve multiple plasmonic Fano resonance. In the proposed nanostructure, the asymmetric line shape originates from the interference between the slot resonator and the new resonator. Therefore, the Fano line shape can be actively controlled by the phase difference of the two resonators and the thickness of the metal nanowall. A scattering matrix method is used to calculate the transmission spectra. Results obtained by the scattering matrix theory are consistent with those from the finite-difference time-domain simulations (FDTD). Moreover, Fano resonances in the proposed structure show high sensitivity, which may have important application in plasmonic nanosensor and modulator.

  4. Plasmonic Optical Tweezers toward Molecular Manipulation: Tailoring Plasmonic Nanostructure, Light Source, and Resonant Trapping.

    Science.gov (United States)

    Shoji, Tatsuya; Tsuboi, Yasuyuki

    2014-09-04

    This Perspective describes recent progress in optical trappings of nanoparticles based on localized surface plasmon. This plasmonic optical trapping has great advantages over the conventional optical tweezers, being potentially applicable for a molecular manipulation technique. We review this novel trapping technique from the viewpoints of (i) plasmonic nanostructure, (ii) the light source for plasmon excitation, and (iii) the polarizability of the trapping target. These findings give us future outlook for plasmonic optical trapping. In addition to a brief review, recent developments on plasmonic optical trapping of soft nanomaterials such as proteins, polymer chains, and DNA will be discussed to point out the important issue for further development on this trapping method. Finally, we explore new directions of plasmonic optical trapping.

  5. Photonic crystal fiber-based surface plasmon resonance sensor with selective analyte channels and graphene-silver deposited core.

    Science.gov (United States)

    Rifat, Ahmmed A; Mahdiraji, G Amouzad; Chow, Desmond M; Shee, Yu Gang; Ahmed, Rajib; Adikan, Faisal Rafiq Mahamd

    2015-05-19

    We propose a surface plasmon resonance (SPR) sensor based on photonic crystal fiber (PCF) with selectively filled analyte channels. Silver is used as the plasmonic material to accurately detect the analytes and is coated with a thin graphene layer to prevent oxidation. The liquid-filled cores are placed near to the metallic channel for easy excitation of free electrons to produce surface plasmon waves (SPWs). Surface plasmons along the metal surface are excited with a leaky Gaussian-like core guided mode. Numerical investigations of the fiber's properties and sensing performance are performed using the finite element method (FEM). The proposed sensor shows maximum amplitude sensitivity of 418 Refractive Index Units (RIU-1) with resolution as high as 2.4 × 10(-5) RIU. Using the wavelength interrogation method, a maximum refractive index (RI) sensitivity of 3000 nm/RIU in the sensing range of 1.46-1.49 is achieved. The proposed sensor is suitable for detecting various high RI chemicals, biochemical and organic chemical analytes. Additionally, the effects of fiber structural parameters on the properties of plasmonic excitation are investigated and optimized for sensing performance as well as reducing the sensor's footprint.

  6. Photonic Crystal Fiber-Based Surface Plasmon Resonance Sensor with Selective Analyte Channels and Graphene-Silver Deposited Core

    Directory of Open Access Journals (Sweden)

    Ahmmed A. Rifat

    2015-05-01

    Full Text Available We propose a surface plasmon resonance (SPR sensor based on photonic crystal fiber (PCF with selectively filled analyte channels. Silver is used as the plasmonic material to accurately detect the analytes and is coated with a thin graphene layer to prevent oxidation. The liquid-filled cores are placed near to the metallic channel for easy excitation of free electrons to produce surface plasmon waves (SPWs. Surface plasmons along the metal surface are excited with a leaky Gaussian-like core guided mode. Numerical investigations of the fiber’s properties and sensing performance are performed using the finite element method (FEM. The proposed sensor shows maximum amplitude sensitivity of 418 Refractive Index Units (RIU−1 with resolution as high as 2.4 × 10−5 RIU. Using the wavelength interrogation method, a maximum refractive index (RI sensitivity of 3000 nm/RIU in the sensing range of 1.46–1.49 is achieved. The proposed sensor is suitable for detecting various high RI chemicals, biochemical and organic chemical analytes. Additionally, the effects of fiber structural parameters on the properties of plasmonic excitation are investigated and optimized for sensing performance as well as reducing the sensor’s footprint.

  7. Photonic Crystal Fiber-Based Surface Plasmon Resonance Sensor with Selective Analyte Channels and Graphene-Silver Deposited Core

    Science.gov (United States)

    Rifat, Ahmmed A.; Mahdiraji, G. Amouzad; Chow, Desmond M.; Shee, Yu Gang; Ahmed, Rajib; Adikan, Faisal Rafiq Mahamd

    2015-01-01

    We propose a surface plasmon resonance (SPR) sensor based on photonic crystal fiber (PCF) with selectively filled analyte channels. Silver is used as the plasmonic material to accurately detect the analytes and is coated with a thin graphene layer to prevent oxidation. The liquid-filled cores are placed near to the metallic channel for easy excitation of free electrons to produce surface plasmon waves (SPWs). Surface plasmons along the metal surface are excited with a leaky Gaussian-like core guided mode. Numerical investigations of the fiber’s properties and sensing performance are performed using the finite element method (FEM). The proposed sensor shows maximum amplitude sensitivity of 418 Refractive Index Units (RIU−1) with resolution as high as 2.4 × 10−5 RIU. Using the wavelength interrogation method, a maximum refractive index (RI) sensitivity of 3000 nm/RIU in the sensing range of 1.46–1.49 is achieved. The proposed sensor is suitable for detecting various high RI chemicals, biochemical and organic chemical analytes. Additionally, the effects of fiber structural parameters on the properties of plasmonic excitation are investigated and optimized for sensing performance as well as reducing the sensor’s footprint. PMID:25996510

  8. Grating-coupled surface plasmon resonance in conical mounting with polarization modulation.

    Science.gov (United States)

    Ruffato, G; Romanato, F

    2012-07-01

    A grating-coupled surface plasmon resonance (GCSPR) technique based on polarization modulation in conical mounting is presented. A metallic grating is azimuthally rotated to support double-surface plasmon polariton excitation and exploit the consequent sensitivity enhancement. Corresponding to the resonance polar angle, a polarization scan of incident light is performed, and reflectivity data are collected before and after functionalization with a dodecanethiol self-assembled monolayer. The output signal exhibits a harmonic dependence on polarization, and the phase term is used as a parameter for sensing. This technique offers the possibility of designing extremely compact, fast, and cheap high-resolution plasmonic sensors based on GCSPR.

  9. Composite modulation of Fano resonance in plasmonic microstructures by electric-field and microcavity

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fan; Wu, Chenyun; Yang, Hong [State Key Laboratory for Mesoscopic Physics and Department of Physics, Peking University, Beijing 100871 (China); Hu, Xiaoyong, E-mail: xiaoyonghu@pku.edu.cn; Gong, Qihuang [State Key Laboratory for Mesoscopic Physics and Department of Physics, Peking University, Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter, Beijing 100871 (China)

    2014-11-03

    Composite modulation of Fano resonance by using electric-field and microcavity simultaneously is realized in a plasmonic microstructure, which consists of a gold nanowire grating inserted into a Fabry-Perot microcavity composited of a liquid crystal layer sandwiched between two indium tin oxide layers. The Fano resonance wavelength varies with the applied voltage and the microcavity resonance. A large shift of 48 nm in the Fano resonance wavelength is achieved when the applied voltage is 20 V. This may provide a new way for the study of multi-functional integrated photonic circuits and chips based on plasmonic microstructures.

  10. Plexcitonics: Coupled and Plasmon-Exciton Systems with Tailorable Properties

    Science.gov (United States)

    2013-11-14

    up a wide range of novel compact solar energy applications such as distillation , desalination, and sterilization and sanitation applications in... distillation and sanitation have been demonstrated. Plasmons, Plexitonic nanostructures, photocatalysis, Fano Resonance, Four wave mixing, SECARS U U U UU 5...solutions without heating the bulk volume of the liquid. Applications in ethanol distillation and sanitation have been demonstrated. Key Accomplishments

  11. Chiral nanophotonics chiral optical properties of plasmonic systems

    CERN Document Server

    Schäferling, Martin

    2017-01-01

    This book describes the physics behind the optical properties of plasmonic nanostructures focusing on chiral aspects. It explains in detail how the geometry determines chiral near-fields and how to tailor their shape and strength. Electromagnetic fields with strong optical chirality interact strongly with chiral molecules and, therefore, can be used for enhancing the sensitivity of chiroptical spectroscopy techniques. Besides a short review of the latest results in the field of plasmonically enhanced enantiomer discrimination, this book introduces the concept of chiral plasmonic near-field sources for enhanced chiroptical spectroscopy. The discussion of the fundamental properties of these light sources provides the theoretical basis for further optimizations and is of interest for researchers at the intersection of nano-optics, plasmonics and stereochemistry. .

  12. Excitation and tuning of Fano-like cavity plasmon resonances in dielectric-metal core-shell resonators

    Science.gov (United States)

    Gu, Ping; Wan, Mingjie; Wu, Wenyang; Chen, Zhuo; Wang, Zhenlin

    2016-05-01

    Fano resonances have been realized in plasmonic systems and have found intriguing applications, in which, however, precisely controlled symmetry breaking or particular arrangement of multiple constituents is usually involved. Although simple core-shell type architectures composed of a spherical dielectric core and a concentric metallic shell layer have been proposed as good candidates that support inherent Fano resonances, these theoretical predictions have rarely seen any detailed experimental investigation. Here, we report on the experimental investigation of the magnetic and electric-based multipolar plasmonic Fano resonances in the dielectric-metal core-shell resonators that are formed by wrapping a nearly perfect metal shell layer around a dielectric sphere. We demonstrate that these Fano resonances originate from the interference between the Mie cavity and sphere plasmon resonances. Moreover, we present that the variation on either the dielectric core size or core refractive index allows for easily tuning the observed Fano resonances over a wide spectral range. Our findings are supported by excellent agreement with analytical calculations, and offer unprecedented opportunities for realizing ultrasensitive bio-sensors, lasing and nonlinear optical devices.Fano resonances have been realized in plasmonic systems and have found intriguing applications, in which, however, precisely controlled symmetry breaking or particular arrangement of multiple constituents is usually involved. Although simple core-shell type architectures composed of a spherical dielectric core and a concentric metallic shell layer have been proposed as good candidates that support inherent Fano resonances, these theoretical predictions have rarely seen any detailed experimental investigation. Here, we report on the experimental investigation of the magnetic and electric-based multipolar plasmonic Fano resonances in the dielectric-metal core-shell resonators that are formed by wrapping a

  13. Plasmon resonance-induced photoluminescence enhancement of CdTe/Cds quantum dots thin films

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hongyu [Nanjing University of Posts and Telecommunications, Nanjing 210003 (China); National Laboratory of Solid State Microstructure and School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China); Xu, Ling, E-mail: xuling@nju.edu.cn [National Laboratory of Solid State Microstructure and School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China); Wu, Yangqing; Xu, Jun; Ma, Zhongyuan; Chen, Kunji [National Laboratory of Solid State Microstructure and School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China)

    2016-11-30

    Highlights: • CdTe/CdS quantum dots/Au nano-rods nano-composite films were fabricated. • PL intensity of the quantum dots films was enhanced due to Au nanorods. • Internal quantum efficiency increased due to localized surface plasmon resonance. • The lifetimes of quantum dots films decreased after interaction with Au nano-rods. - Abstract: CdTe/CdS quantum dots/Au nano-rods nano-composite films were fabricated on planar Si substrates. The optical properties of all samples were investigated and the corresponding simulations were studied. It was found that the photoluminescence intensity of the CdTe/CdS quantum dots films was enhanced about 9-fold after the incorporation of Au nano-rods, the internal quantum efficiency increased from 24.3% to 35.2% due to the localized surface plasmon resonance. The time-resolved luminescence decay curves showed that the lifetimes of CdTe/CdS quantum dots films decreased to 2.8 ns after interaction with Au nano-rods. The results of finite-difference time-domain simulation indicated that Au nano-rods induced the localization of electric field, which enhanced the PL intensity of quantum dots films in the vicinity of Au nano-rods.

  14. Plasmon resonance enhanced temperature-dependent photoluminescence of Si-V centers in diamond

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Shaoheng [State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012 (China); State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012 (China); Song, Jie; Wang, Qiliang; Liu, Junsong; Li, Hongdong, E-mail: hdli@jlu.edu.cn [State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012 (China); Zhang, Baolin [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012 (China)

    2015-11-23

    Temperature dependent optical property of diamond has been considered as a very important factor for realizing high performance diamond-based optoelectronic devices. The photoluminescence feature of the zero phonon line of silicon-vacancy (Si-V) centers in Si-doped chemical vapor deposited single crystal diamond (SCD) with localized surface plasmon resonance (LSPR) induced by gold nanoparticles has been studied at temperatures ranging from liquid nitrogen temperature to 473 K, as compared with that of the SCD counterpart in absence of the LSPR. It is found that with LSPR the emission intensities of Si-V centers are significantly enhanced by factors of tens and the magnitudes of the redshift (width) of the emissions become smaller (narrower), in comparison with those of normal emissions without plasmon resonance. More interestingly, these strong Si-V emissions appear remarkably at temperatures up to 473 K, while the spectral feature was not reported in previous studies on the intrinsic Si-doped diamonds when temperatures are higher than room temperature. These findings would lead to reaching high performance diamond-based devices, such as single photon emitter, quantum cryptography, biomarker, and so forth, working under high temperature conditions.

  15. Detection of glycoprotein using fiber optic surface plasmon resonance sensors with boronic acid

    Science.gov (United States)

    Wang, Fang; Zhang, Yang; Liu, Zigeng; Qian, Siyu; Gu, Yiying; Jing, Zhenguo; Sun, Changsen; Peng, Wei

    2017-04-01

    In this paper, we present a tilted fiber Bragg gratings (TFBG) based surface Plasmon resonance (SPR) label-free sensors with boronic acid derivative (ABA-PBA) as receptor molecule to detect glycoprotein with high sensitivity and selectivity. Tilted fiber Bragg gratings (TFBG) as a near infrared wavelengths detecting element can be able to excite a number of cladding modes whose properties can be detected accurately by measuring the variation of transmitted spectra. A 10° TFBG coated by 50nm gold film was manufactured to stimulate surface plasmon resonance on the surface of the sensor. The sensor was loaded with boronic acid derivative as the recognition molecule which has been widely used in various areas for the recognition matrix of diol-containing biomolecules. The proposed TFBG-SPR sensors exhibit good selectivity and repeatability with the protein concentration sensitivity up to 2.867dB/ (mg/ml) and the limit of detection was 2*10-5g/ml.

  16. Size dependence of multipolar plasmon resonance frequencies and damping rates in simple metal spherical nanoparticles

    CERN Document Server

    Derkachova, A

    2008-01-01

    Multipolar plasmon oscillation frequencies and corresponding damping rates for nanospheres formed of the simplest free-electron metals are studied. The possibility of controlling plasmon features by choosing the size and dielectric properties of the sphere surroundings is discussed. Optical properties of the studied metals are described within the Drude-Sommerfeld model of the dielectric function with effective parameters acounting for the contribution of conduction electrons and of interband transitions. No approximation is made in respect of the size of a particle; plasmon size characteristics are described rigorously. The results of our experiment on sodium nanodroplets [1] are compared with the oscillation frequency size dependence of dipole and quadrupole plasmon.

  17. Resonant-tunnelling-assisted crossing for subwavelenght plasmonic slot waveguides

    DEFF Research Database (Denmark)

    Xiao, Sanshui; Mortensen, Niels Asger

    2008-01-01

    is practically eliminated and the throughput reaches the unity on resonance. Simulation results are in agreement with those from coupled-mode theory. Taking the material loss into account, the symmetry properties of the modes are preserved and the crosstalk remains suppressed, while the throughput is naturally...

  18. Gallium arsenide based surface plasmon resonance for glucose monitoring

    Science.gov (United States)

    Patil, Harshada; Sane, Vani; Sriram, G.; Indumathi, T. S; Sharan, Preeta

    2015-07-01

    The recent trends in the semiconductor and microwave industries has enabled the development of scalable microfabrication technology which produces a superior set of performance as against its counterparts. Surface Plasmon Resonance (SPR) based biosensors are a special class of optical sensors that become affected by electromagnetic waves. It is found that bio-molecular recognition element immobilized on the SPR sensor surface layer reveals a characteristic interaction with various sample solutions during the passage of light. The present work revolves around developing painless glucose monitoring systems using fluids containing glucose like saliva, urine, sweat or tears instead of blood samples. Non-invasive glucose monitoring has long been simulated using label free detection mechanisms and the same concept is adapted. In label-free detection, target molecules are not labeled or altered, and are detected in their natural forms. Label-free detection mechanisms involves the measurement of refractive index (RI) change induced by molecular interactions. These interactions relates the sample concentration or surface density, instead of total sample mass. After simulation it has been observed that the result obtained is highly accurate and sensitive. The structure used here is SPR sensor based on channel waveguide. The tools used for simulation are RSOFT FULLWAVE, MEEP and MATLAB etc.

  19. Surface plasmon resonance immunosensor for cortisol and cortisone determination.

    Science.gov (United States)

    Frasconi, Marco; Mazzarino, Monica; Botrè, Francesco; Mazzei, Franco

    2009-08-01

    In this paper, we present a surface-plasmon-resonance-based immunosensor for the real-time detection of cortisol and cortisone levels in urine and saliva samples. The method proposed here is simple, rapid, economic, sensitive, robust, and reproducible thanks also to the special features of the polycarboxylate-hydrogel-based coatings used for the antibody immobilization. The sensor surface displays a high level of stability during repeated regeneration and affinity reaction cycles. The immunosensor shows high specificity for cortisol and cortisone; furthermore, no significant interferences from other steroids with a similar chemical structure have been observed. The suitability of the hydrogel coating for the prevention of nonspecific binding is also investigated. A good correlation is noticed between the results obtained by the proposed method and the reference liquid chromatography/tandem mass spectrometry method for the analysis of cortisol and cortisone in urine and saliva samples. Standard curves for the detection of cortisol and cortisone in saliva and urine are characterized by a detection limit less than 10 microg l(-1), sufficiently sensitive for both clinical and forensic use.

  20. Surface Plasmon Resonance Biosensor Based on Smart Phone Platforms.

    Science.gov (United States)

    Liu, Yun; Liu, Qiang; Chen, Shimeng; Cheng, Fang; Wang, Hanqi; Peng, Wei

    2015-08-10

    We demonstrate a fiber optic surface plasmon resonance (SPR) biosensor based on smart phone platforms. The light-weight optical components and sensing element are connected by optical fibers on a phone case. This SPR adaptor can be conveniently installed or removed from smart phones. The measurement, control and reference channels are illuminated by the light entering the lead-in fibers from the phone's LED flash, while the light from the end faces of the lead-out fibers is detected by the phone's camera. The SPR-sensing element is fabricated by a light-guiding silica capillary that is stripped off its cladding and coated with 50-nm gold film. Utilizing a smart application to extract the light intensity information from the camera images, the light intensities of each channel are recorded every 0.5 s with refractive index (RI) changes. The performance of the smart phone-based SPR platform for accurate and repeatable measurements was evaluated by detecting different concentrations of antibody binding to a functionalized sensing element, and the experiment results were validated through contrast experiments with a commercial SPR instrument. This cost-effective and portable SPR biosensor based on smart phones has many applications, such as medicine, health and environmental monitoring.

  1. Surface Plasmon Resonance Biosensor Based on Smart Phone Platforms

    Science.gov (United States)

    Liu, Yun; Liu, Qiang; Chen, Shimeng; Cheng, Fang; Wang, Hanqi; Peng, Wei

    2015-08-01

    We demonstrate a fiber optic surface plasmon resonance (SPR) biosensor based on smart phone platforms. The light-weight optical components and sensing element are connected by optical fibers on a phone case. This SPR adaptor can be conveniently installed or removed from smart phones. The measurement, control and reference channels are illuminated by the light entering the lead-in fibers from the phone’s LED flash, while the light from the end faces of the lead-out fibers is detected by the phone’s camera. The SPR-sensing element is fabricated by a light-guiding silica capillary that is stripped off its cladding and coated with 50-nm gold film. Utilizing a smart application to extract the light intensity information from the camera images, the light intensities of each channel are recorded every 0.5 s with refractive index (RI) changes. The performance of the smart phone-based SPR platform for accurate and repeatable measurements was evaluated by detecting different concentrations of antibody binding to a functionalized sensing element, and the experiment results were validated through contrast experiments with a commercial SPR instrument. This cost-effective and portable SPR biosensor based on smart phones has many applications, such as medicine, health and environmental monitoring.

  2. Immunosensor Based on Surface Plasmon Resonance for Antigen Recognition

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A novel immunosensor based on surface plasmon resonance(SPR)has been developed for the recognition of antigen.The sensor was designed on the basis of the fixed angle of incidence and measuring the reflected intensities in a wavelength range of 430-750 nm in real-time. An ultra-bright white light-emitting diode(LED)was used as the light source. Molecular self-assembling in solution was used to form the sensing membrane on gold substrate. It has been seen that the sensitivity of the SPR sensor with 3-mercaptopropionic acid(MPA)/protein A(SPA) sensing membrane is considerably higher than that with MPA or SPA modified Sensing membrane. The kinetic processes on the sensing membrane were studied. The human B factor(Bf), an activator of complement 3(C3), was recognized among the other antigens. This sensor can also be used for other antigen/antibody or adaptor/receptor recognition. Under optimized experimental conditions, the sensor has good selectivity, repeatability, and reversibility.

  3. Surface plasmon resonance characterization of calspermin-calmodulin binding kinetics.

    Science.gov (United States)

    Murphy, Andrew J; Kemp, Fred; Love, John

    2008-05-01

    We cloned, expressed, and purified a chimeric fusion between a soluble green fluorescent protein (smGFP) and the calmodulin binding protein calspermin. We have shown that the fusion protein, labeled smGN, has a K(i) in the calmodulin-dependent cyclic nucleotide phosphodiesterase activity assay of 1.97 nM, i.e., 3800 times smaller than that of the commonly used calmodulin inhibitor W7. Association and dissociation rate constants (k(a) and k(d)) and the dissociation equilibrium constant (K(D)) of smGN for calmodulin were determined using surface plasmon resonance (SPR). The k(a)=1.24 x 10(6)M(-1)s(-1), the k(d)=5.49 x 10(-3)s(-1), and the K(D)=4.42 x 10(-9)M. We also found that the GFP moiety was important for successfully binding calspermin to the surface of the CM5 flow cell at a sufficiently high concentration for SPR, and that this procedure may be used for SPR analysis of other acidic polypeptides, whose pIliquid chromatography-tandem mass spectrometry, indicating a high level of specificity. We conclude that the high affinity and specific binding between smGN and calmodulin make it an easily localized recombinant alternative to chemical calmodulin inhibitors.

  4. Polymer-based chips for surface plasmon resonance sensors

    Science.gov (United States)

    Obreja, Paula; Cristea, Dana; Kusko, Mihai; Dinescu, Adrian

    2008-06-01

    This paper presents a design and low-cost techniques for polymer-based chips for surface plasmon resonance (SPR) sensors. To obtain a polymer chip with a prism, microchannels and a chamber at microscale dimensions, replication techniques in polymers with controlled refractive index have been developed. Photoresist, polydimethylsiloxane (PDMS), polymethylmethacrylate (PMMA) and epoxy resin were used. Silicon dioxide/silicon-based molds have been obtained by anisotropic etching of silicon, and glass prisms were used as masters for replication. The photoresist molds were obtained by optical lithography and were used to obtain the microchannels and the chamber. A liquid prepolymer (PDMS, Sylgard 184) with curing agent at a ratio of 10:1 was used, and a special technique was developed in order to fabricate the components of the structure at the same time. For the deposition and direct patterning of the metallic layers onto the polymer surface, different methods were experimented with, including sputtering. The materials and techniques used to achieve SPR sensors are presented, and the possibilities and limitations of the technology are discussed.

  5. Surface plasmon resonance biosensor for enzymatic detection of small analytes

    Science.gov (United States)

    Massumi Miyazaki, Celina; Makoto Shimizu, Flávio; Mejía-Salazar, J. R.; Oliveira, Osvaldo N., Jr.; Ferreira, Marystela

    2017-04-01

    Surface plasmon resonance (SPR) biosensing is based on the detection of small changes in the refractive index on a gold surface modified with molecular recognition materials, thus being mostly limited to detecting large molecules. In this paper, we report on a SPR biosensing platform suitable to detect small molecules by making use of the mediator-type enzyme microperoxidase-11 (MP11) in layer-by-layer films. By depositing a top layer of glucose oxidase or uricase, we were able to detect glucose or uric acid with limits of detection of 3.4 and 0.27 μmol l‑1, respectively. Measurable SPR signals could be achieved because of the changes in polarizability of MP11, as it is oxidized upon interaction with the analyte. Confirmation of this hypothesis was obtained with finite difference time domain simulations, which also allowed us to discard the possible effects from film roughness changes observed in atomic force microscopy images. The main advantage of this mediator-type enzyme approach is in the simplicity of the experimental method that does not require an external potential, unlike similar approaches for SPR biosensing of small molecules. The detection limits reported here were achieved without optimizing the film architecture, and therefore the performance can in principle be further enhanced, while the proposed SPR platform may be extended to any system where hydrogen peroxide is generated in enzymatic reactions.

  6. Surface plasmon resonance microscopy: Achieving a quantitative optical response

    Science.gov (United States)

    Peterson, Alexander W.; Halter, Michael; Plant, Anne L.; Elliott, John T.

    2016-09-01

    Surface plasmon resonance (SPR) imaging allows real-time label-free imaging based on index of refraction and changes in index of refraction at an interface. Optical parameter analysis is achieved by application of the Fresnel model to SPR data typically taken by an instrument in a prism based figuration. We carry out SPR imaging on a microscope by launching light into a sample and collecting reflected light through a high numerical aperture microscope objective. The SPR microscope enables spatial resolution that approaches the diffraction limit and has a dynamic range that allows detection of subnanometer to submicrometer changes in thickness of biological material at a surface. However, unambiguous quantitative interpretation of SPR changes using the microscope system could not be achieved using the Fresnel model because of polarization dependent attenuation and optical aberration that occurs in the high numerical aperture objective. To overcome this problem, we demonstrate a model to correct for polarization diattenuation and optical aberrations in the SPR data and develop a procedure to calibrate reflectivity to index of refraction values. The calibration and correction strategy for quantitative analysis was validated by comparing the known indices of refraction of bulk materials with corrected SPR data interpreted with the Fresnel model. Subsequently, we applied our SPR microscopy method to evaluate the index of refraction for a series of polymer microspheres in aqueous media and validated the quality of the measurement with quantitative phase microscopy.

  7. Fibre optic surface plasmon resonance sensor system designed for smartphones.

    Science.gov (United States)

    Bremer, Kort; Roth, Bernhard

    2015-06-29

    A fibre optic surface plasmon resonance (SPR) sensor system for smartphones is reported, for the first time. The sensor was fabricated by using an easy-to-implement silver coating technique and by polishing both ends of a 400 µm optical fibre to obtain 45° end-faces. For excitation and interrogation of the SPR sensor system the flash-light and camera at the back side of the smartphone were employed, respectively. Consequently, no external electrical components are required for the operation of the sensor system developed. In a first application example a refractive index sensor was realised. The performance of the SPR sensor system was demonstrated by using different volume concentrations of glycerol solution. A sensitivity of 5.96·10(-4) refractive index units (RIU)/pixel was obtained for a refractive index (RI) range from 1.33 to 1.36. In future implementations the reported sensor system could be integrated in a cover of a smartphone or used as a low-cost, portable point-of-care diagnostic platform. Consequently it offers the potential of monitoring a large variety of environmental or point-of-care parameters in combination with smartphones.

  8. Simultaneous surface acoustic wave and surface plasmon resonance measurements: Electrodeposition and biological interactions monitoring

    Science.gov (United States)

    Friedt, J.-M.; Francis, L.; Reekmans, G.; De Palma, R.; Campitelli, A.; Sleytr, U. B.

    2004-02-01

    We present results from an instrument combining surface acoustic wave propagation and surface plasmon resonance measurements. The objective is to use two independent methods, the former based on adsorbed mass change measurements and the latter on surface dielectric properties variations, to identify physical properties of protein layers, and more specifically their water content. We display mass sensitivity calibration curves using electrodeposition of copper leading to a sensitivity in liquid of 150±15 cm2/g for the Love mode device used here, and the application to monitoring biological processes. The extraction of protein layer thickness and protein to water content ratio is also presented for S-layer proteins under investigation. We obtain, respectively, 4.7±0.7 nm and 75±15%.

  9. Antimicrobial dependence of silver nanoparticles on surface plasmon resonance bands against Escherichia coli

    Science.gov (United States)

    Mlalila, Nichrous G; Swai, Hulda Shaidi; Hilonga, Askwar; Kadam, Dattatreya M

    2017-01-01

    This study presents a simple and trouble-free method for determining the antimicrobial properties of silver nanoparticles (AgNPs) based on the surface plasmon resonance (SPR) bands. AgNPs were prepared by chemical reduction method using silver nitrates as a metallic precursor and formaldehyde (HCHO) as a reducing agent and capped by polyethylene glycol. Effects of several processing variables on the size and shape of AgNPs were monitored using an ultraviolet–visible spectrophotometer based on their SPR bands. The formed particles showing various particle shapes and full width at half maximum (FWHM) were tested against Escherichia coli by surface spreading using agar plates containing equal amounts of selected AgNPs samples. The NPs exhibited higher antimicrobial properties; however, monodispersed spherical NPs with narrow FWHM were more effective against E. coli growth. The NPs prepared are promising candidates in diverse applications such as antimicrobial agents in the food and biomedical industries. PMID:28053512

  10. Highly tunable hybrid metamaterials employing split-ring resonators strongly coupled to graphene surface plasmons

    OpenAIRE

    Liu, Peter Q.; Luxmoore, Isaac. J.; Mikhailov, Sergey A.; Savostianova, Nadja A.; Valmorra, Federico; Faist, Jérôme; Nash, Geoffrey R.

    2015-01-01

    Metamaterials and plasmonics are powerful tools for unconventional manipulation and harnessing of light. Metamaterials can be engineered to possess intriguing properties lacking in natural materials, such as negative refractive index. Plasmonics offers capabilities of confining light in subwavelength dimensions and enhancing light–matter interactions. Recently, the technological potential of graphene-based plasmonics has been recognized as the latter features large tunability, higher field-co...

  11. Silver-poly(vinylidene flouride-trifluoroethylene) nanocomposites with tunable surface-plasmonic properties

    Science.gov (United States)

    Greco, Tonino; Wegener, Michael

    2012-04-01

    Noble metal nanoparticles exhibit tunable optical properties due to surface-plasmon resonances, which depend on the distribution, size and shape of the metallic nanoparticles. In order to handle the nanoparticles they have to be embedded e. g. into a polymer matrix. Here, the synthesis of silver nanoparticles within the polymer matrix is performed by thermal as well as photochemical decomposition of a silver precursor. This in situ synthesis offers the possibility to perform the particle formation before, during or after drying of the soluble polymer matrix. In detail, we focus on the particle generation after processing blends of the polymer and the silver precursor as thin films. A very broad range of mass fractions of nanoparticulate silver from 0.001 up to 0.3 was realized, which allows the adjustment of the surface-plasmon resonance. For low silver nanoparticle contents up to 1 wt.% the surface-plasmon resonance peak is typically observed in the blue spectral region, whereas higher silver amounts cause a high extinction in the visible and near infrared spectral range. As polymeric matrix poly(vinylidene fluoride-trifluoroethylene) was chosen und prepared in a thin-film geometry. On the long range the prepared nanocomposites represent multifunctional materials due to the expected ferroelectric properties of the polymer and the surface-plasmon resonance properties of the silver nanoparticles. In addition to the optical properties, the influence of the particle synthesis on the polymer matrix and morphology is studied. As a result, any degradation of the polymer is excluded.

  12. Gas detection by means of surface plasmon resonance enhanced ellipsometry

    Energy Technology Data Exchange (ETDEWEB)

    Nooke, Alida

    2012-11-01

    This thesis investigated gas sensing by means of surface plasmon resonance enhanced ellipsometry. Surface plasmons were excited in a 40 - 50 nm gold layer by a He-Ne-laser using the Kretschmann configuration, which was arranged on a self-made copper measuring cell. A fixed angle of incidence and the ellipsometric parameter {Delta} as the measured value were used to monitor changes in the gas phase. Different types of gases were investigated: flammable (hydrocarbons and hydrogen), oxidising (oxygen and ozone), toxic (carbon monoxide) and inert (helium and nitrogen). The gas types can be distinguished by their refractive indices, whereas the sensor responds instantly relative to the reference gas with an increase or a decrease in {Delta}. Diluting the analyte gas with a reference gas (nitrogen or air) allowed the detection limits to be determined, these lay in the low % range. The sensor stability was also enhanced as well as the sensitivity by modifying the gold layers with a 3-10 nm additional layer. These additional layers consisted of the inorganic materials TiO{sub 2}, ZrO{sub 2}, MgF{sub 2} and Fe: SnO{sub 2} which were deposited by different coating processes. Surface investigations were made of every utilised layer: scanning electron microscope and atomic force microscope measurements for surface topology and spectroscopic ellipsometry mapping to determine the optical constants and the layer thicknesses. All applied materials protected the gold layer from contaminations and thus prolonged the life span of the sensor. Furthermore, the detection limits were reduced significantly, to the low ppm range. The material Fe: SnO{sub 2} demonstrates a special behaviour in reaction with the toxic gas carbon monoxide: Due to the iron doping, the response to carbon monoxide is extraordinary and concentrations below 1 ppm were detected. In order to approach a future application in industry, the sensor system was adapted to a stainless steel tube. With this measuring

  13. E-Beam Patterned Gold Nanodot Arrays on Optical Fiber Tips for Localized Surface Plasmon Resonance Biochemical Sensing

    Directory of Open Access Journals (Sweden)

    Yongbin Lin

    2010-10-01

    Full Text Available Electron beam lithography (EBL was used to directly pattern periodic gold nanodot arrays on optical fiber tips. Localized surface plasmon resonance of the E-beam patterned gold nanodot arrays on optical fiber tips was utilized for biochemical sensing. The advantage of the optical fiber based localized surface plasmon resonance (LSPR sensors is the convenience to work with and work in harsh environments. An optical fiber tip LSPR refractive index sensor of 196 nm per refractive index unit (RIU sensitivity has been demonstrated. The affinity sensing property of the fiber tip sensor was demonstrated using biotin/streptavidin as the receptor/analyte. The detection limit for streptavidin was determined to be 6 pM.

  14. Plasmonic resonances in hybrid systems of aluminum nanostructured arrays and few layer graphene within the UV-IR spectral range.

    Science.gov (United States)

    González-Campuzano, Ricardo; Saniger, J M; Mendoza, Doroteo

    2017-09-15

    The size-controllable and ordered Al nanocavities and nanodomes arrays were synthesized by electrochemical anodization of aluminum using phosphoric acid, citric acid and mixture both acids. Few layer graphene (FLG) was transferred directly on top of Al nanostructures and their morphology were evaluated by Scanning Electron Microscopy. The interaction between FLG and the plasmonic properties of Al nanostructures arrays were investigated based on specular reflectivity in the UV-Vis-IR range and Raman Spectroscopy. We found that their optical reflectivity was dramatically reduced as compared with unstructured Al. At the same time pronounced reflectivity dips were detectable in the 200 nm-896 nm wavelength range, which were ascribed to plasmonic resonances. The plasmonic properties of these nanostructures do not exhibit evident changes by the presence of FLG in the UV-Vis range of the electromagnetic spectrum. By contrast, the Surface-Enhanced Raman Spectroscopy (SERS) of FLG was observed in nanocavities and nanodomes structures that result in an intensity increase of the characteristic G and 2D bands of FLG induced by the plasmonic properties of Al nanostructures. © 2017 IOP Publishing Ltd.

  15. Low-cost, high performance surface plasmon resonance-compatible films characterized by the surface plasmon resonance technique

    Institute of Scientific and Technical Information of China (English)

    Li Song-Quan; Ye Hong-An; Liu Chun-Yu; Dou Yin-Feng; Huang Yan

    2013-01-01

    A new analytical method based on the surface plasmon resonance (SPR) technique is presented,with which SPR curves for both wavelength and angular modulations can be obtained simultaneously via only a single scan of the incident angle.Using this method,the SPR responses of TiO2-coated Cu films are characterized in the wavelength range from 600 nm to 900 nm.For the first time,we determine the effective optical constants and the thicknesses of TiO2-coated Cu films using the SPR curves of wavelength modulation.The sensitivities of prism-based SPR refractive index sensors using TiO2-coated Cu films are investigated theoretically for both wavelength and angular modulations,the results show that in the case of sensitivity with wavelength modulation,TiO2-coated Cu films are not as good as the Au film,however,they are more suitable than the Au film for SPR refractive index sensors with angular modulation because a higher sensitivity can be achieved.

  16. Near-infrared linewidth narrowing in plasmonic Fano-resonant metamaterials via tuning of multipole contributions

    Science.gov (United States)

    Lim, Wen Xiang; Han, Song; Gupta, Manoj; MacDonald, Kevin F.; Singh, Ranjan

    2017-08-01

    We report on an experimental and computational (multipole decomposition) study of Fano resonance modes in complementary near-IR plasmonic metamaterials. Resonance wavelengths and linewidths can be controlled by changing the symmetry of the unit cell so as to manipulate the balance among multipole contributions. In the present case, geometrically inverting one half of a four-slot (paired asymmetric double bar) unit cell design changes the relative magnitude of magnetic quadrupole and toroidal dipole contributions leading to the enhanced quality factor, figure of merit, and spectral tuning of the plasmonic Fano resonance.

  17. Enhanced electron photoemission by collective lattice resonances in plasmonic nanoparticle-array photodetectors and solar cells

    CERN Document Server

    Zhukovsky, Sergei V; Uskov, Alexander V; Protsenko, Igor E; Lavrinenko, Andrei V

    2013-01-01

    We propose to use collective lattice resonances in plasmonic nanoparticle arrays to enhance photoelectron emission in Schottky-barrier photodetectors and solar cells. We show that the interaction of lattice resonances (the Rayleigh anomaly) and individual particle excitations (localized surface plasmon resonances) leads to stronger local field enhancement and significant increase of the photocurrent compared to the case when only individual particle excitations are present. The results can be used to design new photodetectors with highly selective, tunable spectral response, able to detect photons with the energy below the semiconductor bandgap, and to develop solar cells with increased efficiency.

  18. Resonant terahertz absorption by plasmons in grating-gate GaN HEMT structures

    Science.gov (United States)

    Muravjov, A. V.; Veksler, D. B.; Hu, X.; Gaska, R.; Pala, N.; Saxena, H.; Peale, R. E.; Shur, M. S.

    2009-05-01

    Pronounced resonant absorption and frequency dispersion associated with an excitation of collective 2D plasmons have been observed in terahertz (0.5-4THz) transmission spectra of grating-gate 2D electron gas AlGaN/GaN HEMT (high electron mobility transistor) structures at cryogenic temperatures. The resonance frequencies correspond to plasmons with wavevectors equal to the reciprocal-lattice vectors of the metal grating, which serves both as a gate electrode for the HEMT and a coupler between plasmons and incident terahertz radiation. The resonances are tunable by changing the applied gate voltage, which controls 2D electron gas concentration in the channel. The effect can be used for resonant detection of terahertz radiation and for "on-chip" terahertz spectroscopy.

  19. Localized surface plasmons selectively coupled to resonant light in tubular microcavities

    CERN Document Server

    Yin, Yin; Böttner, Stefan; Yuan, Feifei; Giudicatti, Silvia; Naz, Ehsan Saei Ghareh; Ma, Libo; Schmidt, Oliver G

    2016-01-01

    Vertical gold-nanogaps are created on microtubular cavities to explore the coupling between resonant light supported by the microcavities and surface plasmons localized at the nanogaps. Selective coupling of optical axial modes and localized surface plasmons critically depends on the exact location of the gold-nanogap on the microcavities which is conveniently achieved by rolling-up specially designed thin dielectric films into three dimensional microtube ring resonators. The coupling phenomenon is explained by a modified quasi-potential model based on perturbation theory. Our work reveals the coupling of surface plasmon resonances localized at the nanoscale to optical resonances confined in microtubular cavities at the microscale, implying a promising strategy for the investigation of light-matter interactions.

  20. Blueshift of the surface plasmon resonance in silver nanoparticles studied with EELS

    DEFF Research Database (Denmark)

    Raza, Søren; Stenger, Nicolas; Kadkhodazadeh, Shima

    2013-01-01

    We study the surface plasmon (SP) resonance energy of isolated spherical Ag nanoparticles dispersed on a silicon nitride substrate in the diameter range 3.5–26 nm with monochromated electron energy-loss spectroscopy. A significant blueshift of the SP resonance energy of 0.5 eV is measured when...

  1. High resolution grating-assisted surface plasmon resonance fiber optic aptasensor.

    Science.gov (United States)

    Albert, Jacques; Lepinay, Sandrine; Caucheteur, Christophe; Derosa, Maria C

    2013-10-01

    A surface plasmon resonance biochemical sensor based on a tilted fiber Bragg grating imprinted in a single mode fiber core is demonstrated. A 30-50 nm thick gold coating on the cladding of the fiber provides the support for surface plasmon waves whose interaction with attached biomolecules is monitored at near infrared wavelengths near 1,550 nm. The transmission spectrum of the sensor provides a fine comb of narrowband resonances that overlap with the broader absorption of the surface plasmon and thus provide a unique tool to measure small shifts of the plasmon with high accuracy. The attachment on the gold surfaces of aptamers with specific affinities for proteins provides the required target-analyte system and is shown to be functional in the framework of our sensing device. The implementation of the sensor either as a stand-alone device or as part of a multi-sensor platform is also described. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Anisotropic emission from multilayered plasmon resonator nanocomposites of isotropic semiconductor quantum dots.

    Science.gov (United States)

    Ozel, Tuncay; Nizamoglu, Sedat; Sefunc, Mustafa A; Samarskaya, Olga; Ozel, Ilkem O; Mutlugun, Evren; Lesnyak, Vladimir; Gaponik, Nikolai; Eychmuller, Alexander; Gaponenko, Sergey V; Demir, Hilmi Volkan

    2011-02-22

    We propose and demonstrate a nanocomposite localized surface plasmon resonator embedded into an artificial three-dimensional construction. Colloidal semiconductor quantum dots are assembled between layers of metal nanoparticles to create a highly strong plasmon-exciton interaction in the plasmonic cavity. In such a multilayered plasmonic resonator architecture of isotropic CdTe quantum dots, we observed polarized light emission of 80% in the vertical polarization with an enhancement factor of 4.4, resulting in a steady-state anisotropy value of 0.26 and reaching the highest quantum efficiency level of 30% ever reported for such CdTe quantum dot solids. Our electromagnetic simulation results are in good agreement with the experimental characterization data showing a significant emission enhancement in the vertical polarization, for which their fluorescence decay lifetimes are substantially shortened by consecutive replication of our unit cell architecture design. Such strongly plasmon-exciton coupling nanocomposites hold great promise for future exploitation and development of quantum dot plasmonic biophotonics and quantum dot plasmonic optoelectronics.

  3. Sensitivity Dependence of Surface Plasmon Resonance Based Sensors on Prism Refractive Index

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    We theoretically and experimentally demonstrate that refractive index of the prism used toload metal film has significant influence on sensitivity of surface plasmon resonance based sensors. Theprism with lower refractive index gives the sensors a higher sensitivity in detecting refractive index varia-tions of a sample. We attribute this effect to the fact that a prism with low refractive index will increasecoupling distance between surface plasmons and the medium under investigation.

  4. Overview of the Characteristics of Micro- and Nano-Structured Surface Plasmon Resonance Sensors

    Directory of Open Access Journals (Sweden)

    Byoungho Lee

    2011-01-01

    Full Text Available The performance of bio-chemical sensing devices has been greatly improved by the development of surface plasmon resonance (SPR based sensors. Advancements in micro- and nano-fabrication technologies have led to a variety of structures in SPR sensing systems being proposed. In this review, SPR sensors (from typical Kretschmann prism configurations to fiber sensor schemes with micro- or nano-structures for local light field enhancement, extraordinary optical transmission, interference of surface plasmon waves, plasmonic cavities, etc. are discussed. We summarize and compare their performances and present guidelines for the design of SPR sensors.

  5. Surface Plasmon Resonance Immunosensor for the Detection of Campylobacter jejuni

    Directory of Open Access Journals (Sweden)

    Noor Azlina Masdor

    2017-05-01

    Full Text Available Campylobacteriosis is an internationally important foodborne disease caused by Campylobacter jejuni. The bacterium is prevalent in chicken meat and it is estimated that as much as 90% of chicken meat on the market may be contaminated with the bacterium. The current gold standard for the detection of C. jejuni is the culturing method, which takes at least 48 h to confirm the presence of the bacterium. Hence, the aim of this work was to investigate the development of a Surface Plasmon Resonance (SPR sensor platform for C. jejuni detection. Bacterial strains were cultivated in-house and used in the development of the sensor. SPR sensor chips were first functionalized with polyclonal antibodies raised against C. jejuni using covalent attachment. The gold chips were then applied for the direct detection of C. jejuni. The assay conditions were then optimized and the sensor used for C. jejuni detection, achieving a detection limit of 8 × 106 CFU·mL−1. The sensitivity of the assay was further enhanced to 4 × 104 CFU·mL−1 through the deployment of a sandwich assay format using the same polyclonal antibody. The LOD obtained in the sandwich assay was higher than that achieved using commercial enzyme-linked immunosorbent assay (ELISA (106–107 CFU·mL−1. This indicate that the SPR-based sandwich sensor method has an excellent potential to replace ELISA tests for C. jejuni detection. Specificity studies performed with Gram-positive and Gram-negative bacteria, demonstrated the high specific of the sensor for C. jejuni.

  6. Effect of irregularities of nanosatellites position and size on collective electric and magnetic plasmonic resonances in spherical nanoclusters.

    Science.gov (United States)

    Vallecchi, Andrea; Albani, Matteo; Capolino, Filippo

    2013-03-25

    Spherical nanoclusters (NCs) with a central dielectric core surrounded by several satellite plasmonic nanospheres have been recently investigated as aggregates supporting electric and magnetic collective resonances. Notably, the collective magnetic resonance has been exploited to provide magnetic properties in optics, i.e., materials with macroscopic relative permeability different from unity. The NCs discussed in this paper can be realized using state-of-the-art nanochemistry self-assembly techniques. Accordingly, perfectly regular disposition of the nanoplasmonic satellites is not possible and this paper constitutes the first comprehensive analysis of the effect of such irregularities onto the electric and magnetic collective resonances. In particular we will show that the peak of the scattering cross section associated to the magnetic resonance is very sensitive to certain irregularities and significantly less to others. It is shown here that "artificial magnetic" properties of NCs are preserved for certain degrees of irregularities of the nanosatellites positions, however they are strongly affected by irregularities in the plasmonic nanosatellites sizes and by the presence of "defects" caused by the absence of satellites in the process of self-assembly around the dielectric core. The "artificial electric" resonance is instead less affected by irregularities mainly because of its wider frequency bandwidth.

  7. 金纳米球壳表面等离激元共振波长调谐特性研究%Tunable properties of localized surface plasmon resonance wavelength of gold nanoshell∗

    Institute of Scientific and Technical Information of China (English)

    张兴坊; 闫昕

    2013-01-01

    The effects of shell thickness, inner core size, and dielectric constants of core and embedding medium on the localized surface plasmon resonance wavelength of gold nanoshell are investigated by Mie theory. The results show that the extinction peak of gold nanoshell is first blue-shifted and then red-shifted with the increase of shell thickness, that the shift shell thickness corresponding to quadrupolar wavelength is greater than that corresponding to dipolar wavelength, and that the ratio of the shift shell thickness to the inner core size decreases with the increase of inner core size, and increases with the increase of dielectric constant of inner core or embedding medium. The resonance peaks in the scattering spectra have similar phenomena to those in extinction spectra as the shell thickness increases. The shift of the spectral peak is ascribed to the plasmon hybridization and phase retardation effect.%  理论研究了金纳米球壳的几何结构参数,及物理参量对局域表面等离激元共振波长调谐特性的影响。结果表明,随着壳层厚度的增大,球壳消光共振峰先蓝移后红移,高阶峰转向时对应的壳层厚度比低阶峰大,且该厚度与球壳内径的比值随内径尺寸的增大而减小,随内核材料或外界环境介电常数的增大而增大,散射共振峰也有类似的移动规律。利用电子杂化效应和相位延迟效应对该现象进行了理论解释。

  8. Surface plasmon resonance sensor based on golden nanoparticles and cold vapour generation technique for the detection of mercury in aqueous samples

    Science.gov (United States)

    Castillo, Jimmy; Chirinos, José; Gutiérrez, Héctor; La Cruz, Marie

    2017-09-01

    In this work, a surface plasmon resonance sensor for determination of Hg based on golden nanoparticles was developed. The sensor follows the change of the signal from solutions in contact with atomic mercury previously generated by the reaction with sodium borohydride. Mie theory predicts that Hg film, as low as 5 nm, induced a significant reduction of the surface plasmon resonance signal of 40 nm golden nanoparticles. This property was used for quantification purposes in the sensor. The device provide limits of detection of 172 ng/L that can compared with the 91 ng/L obtained with atomic fluorescence, a common technique used for Hg quantification in drinking water. This result was relevant, considering that it was not necessary to functionalize the nanoparticles or use nanoparticles deposited in a substrate. Also, thanks that Hg is released from the matrix, the surface plasmon resonance signal was not affected by concomitant elements in the sample.

  9. Influence of dopant distribution on the plasmonic properties of indium tin oxide nanocrystals.

    Science.gov (United States)

    Lounis, Sebastien D; Runnerstrom, Evan L; Bergerud, Amy; Nordlund, Dennis; Milliron, Delia J

    2014-05-14

    Doped metal oxide nanocrystals represent an exciting frontier for colloidal synthesis of plasmonic materials, displaying unique optoelectronic properties and showing promise for a variety of applications. However, fundamental questions about the nature of doping in these materials remain. In this article, the strong influence of radial dopant distribution on the optoelectronic properties of colloidal indium tin oxide nanocrystals is reported. Comparing elemental depth-profiling by X-ray photoelectron spectroscopy (XPS) with detailed modeling and simulation of the optical extinction of these nanocrystals using the Drude model for free electrons, a correlation between surface segregation of tin ions and the average activation of dopants is observed. A strong influence of surface segregation of tin on the line shape of the localized surface plasmon resonance (LSPR) is also reported. Samples with tin segregated near the surface show a symmetric line shape that suggests weak or no damping of the plasmon by ionized impurities. It is suggested that segregation of tin near the surface facilitates compensation of the dopant ions by electronic defects and oxygen interstitials, thus reducing activation. A core-shell model is proposed to explain the observed differences in line shape. These results demonstrate the nuanced role of dopant distribution in determining the optoelectronic properties of semiconductor nanocrystals and suggest that more detailed study of the distribution and structure of defects in plasmonic colloidal nanocrystals is warranted.

  10. Calculation of curvature dependent surface plasmon resonance in gold nanospheroid and nanoshell

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Jian, E-mail: jianzhusummer@163.co [Xi' an Jiaotong University, Institute of Modern Physics, School of Science (China)

    2009-05-15

    In this paper, theoretical calculations based on dipole-limit are performed to investigate the effects of curvature on the surface plasmon resonance (SPR) properties of nanometer size gold spheroid and shell. By comparing the aspect ratio with the shell thickness, we demonstrated that the curvature radius is a common better factor that can be used to predict the SPR wavelength and shift fashion. For nanospheroid, increasing the ratio of curvature radius corresponding to the climaxes leads to an increase in the ratio of SPR wavelength, whereas increasing the ratio of curvature radius of outer and inner surface in nanoshell leads to an decrease in the ratio of SPR wavelength. As a morphologic factor, curvature radius plays an important role in affecting the distribution of electron density, and consequently controlling the SPR frequency.

  11. Broadband tunability of surface plasmon resonance in graphene-coating silica nanoparticles

    Science.gov (United States)

    Zhe, Shi; Yang, Yang; Lin, Gan; Zhi-Yuan, Li

    2016-05-01

    Graphene decorated nanomaterials and nanostructures can potentially be used in military and medical science applications. In this article, we study the optical properties of a graphene wrapping silica core-shell spherical nanoparticle under illumination of external light by using the Mie theory. We find that the nanoparticle can exhibit surface plasmon resonance (SPR) that can be broadly tuned from mid infrared to near infrared via simply changing the geometric parameters. A simplified equivalent dielectric permittivity model is developed to better understand the physics of SPR, and the calculation results agree well qualitatively with the rigorous Mie theory. Both calculations suggest that a small radius of graphene wrapping nanoparticle with high Fermi level could move the SPR wavelength of graphene into the near infrared regime. Project supported by the National Natural Science Foundation of China (Grant Nos. 11204365 and 11434017) and the National Basic Research Program of China (Grant No. 2013CB632704).

  12. Plasmon resonance-induced photoluminescence enhancement of CdTe/Cds quantum dots thin films

    Science.gov (United States)

    Wang, Hongyu; Xu, Ling; Wu, Yangqing; Xu, Jun; Ma, Zhongyuan; Chen, Kunji

    2016-11-01

    CdTe/CdS quantum dots/Au nano-rods nano-composite films were fabricated on planar Si substrates. The optical properties of all samples were investigated and the corresponding simulations were studied. It was found that the photoluminescence intensity of the CdTe/CdS quantum dots films was enhanced about 9-fold after the incorporation of Au nano-rods, the internal quantum efficiency increased from 24.3% to 35.2% due to the localized surface plasmon resonance. The time-resolved luminescence decay curves showed that the lifetimes of CdTe/CdS quantum dots films decreased to 2.8 ns after interaction with Au nano-rods. The results of finite-difference time-domain simulation indicated that Au nano-rods induced the localization of electric field, which enhanced the PL intensity of quantum dots films in the vicinity of Au nano-rods.

  13. Properties of localized surface plasmon resonance of gold nanoshell pairs%金纳米球壳对的局域表面等离激元共振特性分析

    Institute of Scientific and Technical Information of China (English)

    邹伟博; 周骏; 金理; 张昊鹏

    2012-01-01

    应用有限元方法,研究金纳米球壳对的几何结构参数及物理参量对其表面等离激元共振的散射及消光光谱的影响,并根据等离激元杂化理论进行了理论分析.结果表明,随着金壳厚度的增加,金纳米球壳对的散射及消光共振峰先发生蓝移而后红移,而随着金纳米球壳间隙的减小,或者随着金纳米球壳的内核尺寸或内核介质折射率的增大,散射及消光共振峰均发生红移;随着金壳厚度或内核尺寸减小,或者随着内核介质折射率增大,金纳米球壳对的散射与消光共振强度减弱,而随着金壳间隙的减小,金纳米球壳对的散射共振强度先增强后减弱,而消光共振强度逐渐增强,数值模拟与理论分析一致.%The characteristics of scatting and extinction spectra of gold nanoshell pairs, dependent on the its geometry and physical param- eters, are investigated by the Finite Element Method based on the plasmon hybridization theory. The numerical results indicate that the resonante peaks in the scattering spectra and the extinction spectra emerge from blue-shift to red-shift with the increases of the thickness of gold nanoshells, whereas they present the red-shift with the decrease of the interparticle separation or with the increases of the size and the refractive index of inner core of gold nanoshells. In the same time, for the case of decreasing the inner core size and the shell thickness or increasing the refractive index of inner core, the intensity of the scattering resonance and the extinction resonance decrease. And, with the decrease of the interparticle separation, the intensity of the scattering resonance of gold nanoshell pairs trends to first increase and then decrease, while the intensity of the extinction resonance increases gradually. All the above is in agreement with the analysis of the plasmon hybridization theory.

  14. Plasmonic extinction in gold nanoparticle-polymer films as film thickness and nanoparticle separation decrease below resonant wavelength

    Science.gov (United States)

    Dunklin, Jeremy R.; Bodinger, Carter; Forcherio, Gregory T.; Keith Roper, D.

    2017-01-01

    Plasmonic nanoparticles embedded in polymer films enhance optoelectronic properties of photovoltaics, sensors, and interconnects. This work examined optical extinction of polymer films containing randomly dispersed gold nanoparticles (AuNP) with negligible Rayleigh scattering cross-sections at particle separations and film thicknesses less than (sub-) to greater than (super-) the localized surface plasmon resonant (LSPR) wavelength, λLSPR. Optical extinction followed opposite trends in sub- and superwavelength films on a per nanoparticle basis. In ˜70-nm-thick polyvinylpyrrolidone films containing 16 nm AuNP, measured resonant extinction per particle decreased as particle separation decreased from ˜130 to 76 nm, consistent with trends from Maxwell Garnett effective medium theory and coupled dipole approximation. In ˜1-mm-thick polydimethylsiloxane films containing 16-nm AuNP, resonant extinction per particle plateaued at particle separations ≥λLSPR, then increased as particle separation radius decreased from ˜514 to 408 nm. Contributions from isolated particles, interparticle interactions and heterogeneities in sub- and super-λLSPR films containing AuNP at sub-λLSPR separations were examined. Characterizing optoplasmonics of thin polymer films embedded with plasmonic NP supports rational development of optoelectronic, biomedical, and catalytic activity using these nanocomposites.

  15. Localized surface plasmon resonance frequency tuning in highly doped InAsSb/GaSb one-dimensional nanostructures

    Science.gov (United States)

    Milla, M. J.; Barho, F.; González-Posada, F.; Cerutti, L.; Bomers, M.; Rodriguez, J.-B.; Tournié, E.; Taliercio, T.

    2016-10-01

    We report a detailed analysis of the influence of the doping level and nanoribbon width on the localized surface plasmon resonance (LSPR) by means of reflectance measurements. The plasmonic system, based on one-dimensional periodic gratings of highly Si-doped InAsSb/GaSb semiconductor nanostructures, is fabricated by a simple, accurate and large-area technique fabrication. Increasing the doping level blueshifts the resonance peak while increasing the ribbon width results in a redshift, as confirmed by numerical simulations. This provides an efficient means of fine-tuning the LSPR properties to a target purpose of between 8-20 μm (1250-500 cm-1). Finally, we show surface plasmon resonance sensing to absorbing polymer layers. We address values of the quality factor, sensitivity and figure of merit of 16 700 nm RIU-1 and 2.5, respectively. These results demonstrate Si-doped InAsSb/GaSb to be a low-loss/high sensitive material making it very promising for the development of biosensing devices in the mid-infrared.

  16. Probing the symmetry and phase of localised surface plasmon resonances with modified electron probes

    CERN Document Server

    Guzzinati, Giulio; Lourenço--Martins, Hugo; Martin, Jerôme; Kociak, Mathieu; Verbeeck, Jo

    2016-01-01

    Plasmonics, the science and technology of the interaction of light with metallic objects, is fundamentally changing the way we can detect, generate and manipulate light at the nanoscale. While the field is progressing swiftly thanks to the availability of nanoscale manufacturing and analysis methods, fundamental properties such as the symmetries of the plasmonic excitations cannot be accessed by direct measurements, leading to a partial and sometimes incorrect understanding of their properties. Here we overcome this limitation by deliberately shaping the wave--function of a free electron beam to match the symmetry of the plasmonic excitations in a modified transmission electron microscope. We show experimentally and theoretically that this offers selective detection of specific plasmon modes within metallic nanoparticles while filtering out modes with other symmetries. This method shows some resemblance to the widespread use of polarised light for the selective excitation of plasmon modes but adds the advanta...

  17. Abnormal thermal effects on the surface plasmon resonance of Ag nanoparticles on the surface of silicon

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Han; Ding, Ruiqiang [State Key Laboratory for Alternate Electrical Power System with Renewable Energy Sources, School of Renewable Energy, North China Electric Power University, Beijing 102206 (China); Li, Meicheng, E-mail: mcli@ncepu.edu.cn [State Key Laboratory for Alternate Electrical Power System with Renewable Energy Sources, School of Renewable Energy, North China Electric Power University, Beijing 102206 (China); Suzhou Institute, North China Electric Power University, Suzhou 215123 (China); Li, Yingfeng; Yang, Ganghai; Song, Dandan; Yu, Yue; Trevor, Mwenya [State Key Laboratory for Alternate Electrical Power System with Renewable Energy Sources, School of Renewable Energy, North China Electric Power University, Beijing 102206 (China)

    2015-06-01

    The thermal effects on the surface plasmon resonance (SPR) of Ag nanoparticles on the silicon surface have been studied. It is found that unusual blue shifts and narrowing of the SPR troughs occur as the temperature increases from 323 K to 363 K. At low temperature range (from 273 K to 323 K), the SPR troughs have the normal red shifts and broadening as in previous studies. The change of SPR is attributed to the thermal induced electron transport between particles and substrate, and is analyzed using samples with different particle sizes. This work reveals the mechanism of thermal effects on the plasmonic properties of Ag nanoparticles on the surface of silicon and offers useful information for designing of SPR devices. - Highlights: • Unusual blue shift of the SPR troughs is observed at 343 K. • Red shift of the SPR troughs is observed at 323 K. • The mechanism relies on the thermal induced surface electron transport. • Particle sizes play an important role in the change of the SPR troughs.

  18. Surface Plasmon Resonance-Based Fiber Optic Sensors Utilizing Molecular Imprinting

    Directory of Open Access Journals (Sweden)

    Banshi D. Gupta

    2016-08-01

    Full Text Available Molecular imprinting is earning worldwide attention from researchers in the field of sensing and diagnostic applications, due to its properties of inevitable specific affinity for the template molecule. The fabrication of complementary template imprints allows this technique to achieve high selectivity for the analyte to be sensed. Sensors incorporating this technique along with surface plasmon or localized surface plasmon resonance (SPR/LSPR provide highly sensitive real time detection with quick response times. Unfolding these techniques with optical fiber provide the additional advantages of miniaturized probes with ease of handling, online monitoring and remote sensing. In this review a summary of optical fiber sensors using the combined approaches of molecularly imprinted polymer (MIP and the SPR/LSPR technique is discussed. An overview of the fundamentals of SPR/LSPR implementation on optical fiber is provided. The review also covers the molecular imprinting technology (MIT with its elementary study, synthesis procedures and its applications for chemical and biological anlayte detection with different sensing methods. In conclusion, we explore the advantages, challenges and the future perspectives of developing highly sensitive and selective methods for the detection of analytes utilizing MIT with the SPR/LSPR phenomenon on optical fiber platforms.

  19. Surface plasmon resonance in nanostructured Ag incorporated ZnS films

    Directory of Open Access Journals (Sweden)

    S. R. Chalana

    2015-10-01

    Full Text Available Silver incorporated zinc sulfide thin films are prepared by RF magnetron sputtering technique and the influence of silver incorporation on the structural, optical and luminescence properties is analyzed using techniques like grazing incidence X-Ray diffraction (GIXRD, atomic force microscopy (AFM, field emission scanning electron microscopy (FESEM, energy dispersive X-ray spectroscopy (EDS, micro-Raman spectroscopy, UV-Vis spectroscopy and laser photoluminescence spectroscopy. XRD analysis presents hexagonal wurtzite structure for the films. A reduction of crystallinity of the films is observed due to Ag incorporation. The Raman spectral analysis confirms the reduction of crystallinity and increase of strain due to the Ag incorporation. AFM analysis reveals a rough surface morphology for the undoped film and Ag incorporation makes the films uniform, dense and smooth. A blue shift of band gap energy with increase in Ag incorporation is observed due to quantum confinement effect. An absorption band (450-650 nm region due to surface plasmon resonance of the Ag clusters present in the ZnS matrix is observed for the samples with higher Ag incorporation. The complex dielectric constant, loss factor and distribution of volume and surface energy loss of the ZnS thin films are calculated. Laser photoluminescence measurements gives an intense bluish green emission from the ZnS films and a quenching of the PL emission is observed which can be due to the metal plasmonic absorption and non-radiative energy transfer due to Ag incorporation.

  20. Resonant plasmonic terahertz detection in vertical graphene-base hot-electron transistors

    Energy Technology Data Exchange (ETDEWEB)

    Ryzhii, V. [Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577 (Japan); Center for Photonics and Infrared Engineering, Bauman Moscow State Technical University and Institute of Ultra High Frequency Semiconductor Electronics of RAS, Moscow 111005 (Russian Federation); Otsuji, T. [Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577 (Japan); Ryzhii, M. [Department of Computer Science and Engineering, University of Aizu, Aizu-Wakamatsu 965-8580 (Japan); Mitin, V. [Department of Electrical Engineering, University at Buffalo, SUNY, Buffalo, New York 1460-1920 (United States); Shur, M. S. [Department of Electrical, Computer, and System Engineering and Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)

    2015-11-28

    We analyze dynamic properties of vertical graphene-base hot-electron transistors (GB-HETs) and consider their operation as detectors of terahertz (THz) radiation using the developed device model. The GB-HET model accounts for the tunneling electron injection from the emitter, electron propagation across the barrier layers with the partial capture into the GB, and the self-consistent oscillations of the electric potential and the hole density in the GB (plasma oscillations), as well as the quantum capacitance and the electron transit-time effects. Using the proposed device model, we calculate the responsivity of GB-HETs operating as THz detectors as a function of the signal frequency, applied bias voltages, and the structural parameters. The inclusion of the plasmonic effect leads to the possibility of the GB-HET operation at the frequencies significantly exceeding those limited by the characteristic RC-time. It is found that the responsivity of GB-HETs with a sufficiently perfect GB exhibits sharp resonant maxima in the THz range of frequencies associated with the excitation of plasma oscillations. The positions of these maxima are controlled by the applied bias voltages. The GB-HETs can compete with and even surpass other plasmonic THz detectors.

  1. Surface plasmon resonance in nanostructured Ag incorporated ZnS films

    Energy Technology Data Exchange (ETDEWEB)

    Chalana, S. R.; Mahadevan Pillai, V. P., E-mail: vpmpillai9@gmail.com [Department of Optoelectronics, University of Kerala, Kariavattom, Thiruvananthapuram– 695581, Kerala (India); Ganesan, V. [UGC-DAE Consortium for Scientific Research, Khandwa Road, Indore- 452017, Madhyapradesh (India)

    2015-10-15

    Silver incorporated zinc sulfide thin films are prepared by RF magnetron sputtering technique and the influence of silver incorporation on the structural, optical and luminescence properties is analyzed using techniques like grazing incidence X-Ray diffraction (GIXRD), atomic force microscopy (AFM), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), micro-Raman spectroscopy, UV-Vis spectroscopy and laser photoluminescence spectroscopy. XRD analysis presents hexagonal wurtzite structure for the films. A reduction of crystallinity of the films is observed due to Ag incorporation. The Raman spectral analysis confirms the reduction of crystallinity and increase of strain due to the Ag incorporation. AFM analysis reveals a rough surface morphology for the undoped film and Ag incorporation makes the films uniform, dense and smooth. A blue shift of band gap energy with increase in Ag incorporation is observed due to quantum confinement effect. An absorption band (450-650 nm region) due to surface plasmon resonance of the Ag clusters present in the ZnS matrix is observed for the samples with higher Ag incorporation. The complex dielectric constant, loss factor and distribution of volume and surface energy loss of the ZnS thin films are calculated. Laser photoluminescence measurements gives an intense bluish green emission from the ZnS films and a quenching of the PL emission is observed which can be due to the metal plasmonic absorption and non-radiative energy transfer due to Ag incorporation.

  2. Proposal of In-process Measurement for Micro-stereolithography Using Surface Plasmon Resonance

    Science.gov (United States)

    Michihata, Masaki; Takamasu, Kiyoshi; Takahashi, Satoru

    There is strong demand for the development of micro-manufacturing techniques to realize three-dimensional micro-structures. One of the important techniques is micro-stereolithography, which solidifies photopolymer resin using optical energy. Regarding the manufacturing accuracy of micro-stereolithography, structural errors should be improved; however, they are influenced by optical conditions, the material conditions of resins, and so on. Because dimensions and shapes can be evaluated only after completing all of the manufacturing processes, in-process measurement is useful for improving manufacturing accuracy. The solidified photopolymer resin changes its refractive index as little as 0.04, compared with the case before solidification. In this study, the surface plasmon resonance (SPR) is proposed to measure minute changes of the refractive index. The condition required to excite SPR is highly sensitive to both the refractive index of environmental materials and the thickness of (and materials used in) the plasmonic substrate. In this paper, the novel method and fundamental properties are discussed.

  3. Plasmonic Properties of Vertically Aligned Nanowire Arrays

    Directory of Open Access Journals (Sweden)

    Hua Qi

    2012-01-01

    Full Text Available Nanowires (NWs/Ag sheath composites were produced to investigate plasmonic coupling between vertically aligned NWs for surface-enhanced Raman scattering (SERS applications. In this investigation, two types of vertical NW arrays were studied; those of ZnO NWs grown on nanosphere lithography patterned sapphire substrate via vapor-liquid-solid (VLS mechanism and Si NW arrays produced by wet chemical etching. Both types of vertical NW arrays were coated with a thin layer of silver by electroless silver plating for SERS enhancement studies. The experimental results show extremely strong SERS signals due to plasmonic coupling between the NWs, which was verified by COMSOL electric field simulations. We also compared the SERS enhancement intensity of aligned and random ZnO NWs, indicating that the aligned NWs show much stronger and repeatable SERS signal than those grown in nonaligned geometries.

  4. Direct determination of the resonance properties of metallic conical nanoantennas.

    Science.gov (United States)

    Tuccio, Salvatore; Razzari, Luca; Alabastri, Alessandro; Toma, Andrea; Liberale, Carlo; De Angelis, Francesco; Candeloro, Patrizio; Das, Gobind; Giugni, Andrea; Di Fabrizio, Enzo; Zaccaria, Remo Proietti

    2014-02-01

    We present a simple method that is able to predict the resonant frequencies of a metallic conical nanoantenna. The calculation is based on an integral relation that takes into account the dependence of the effective refractive index of the plasmonic mode on the cone radius. Numerical simulations retrieving the near field properties of nanocones with different lengths are also performed for comparison. The fine agreement between the two approaches demonstrates the validity of our method.

  5. Direct determination of the resonance properties of metallic conical nanoantennas

    KAUST Repository

    Tuccio, Salvatore

    2014-01-01

    We present a simple method that is able to predict the resonant frequencies of a metallic conical nanoantenna. The alculation is based on an integral relation that takes into account the dependence of the effective refractive index of the plasmonic mode on the cone radius. Numerical simulations retrieving the near field properties of nanocones with different lengths are also performed for comparison. The fine agreement between the two approaches demonstrates the validity of our method. © 2014 Optical Society of America.

  6. Far-Field Plasmonic Resonance Enhanced Nano-Particle Image Velocimetry within a Micro Channel

    CERN Document Server

    Zhang, Zhili; Haque, Sara S; Zhang, Mingjun

    2010-01-01

    In this paper, a novel far-field plasmonic resonance enhanced nanoparticle-seeded Particle Image Velocimetry (nPIV) has been demonstrated to measure the velocity profile in a micro channel. Chemically synthesized silver nanoparticles have been used to seed the flow in the micro channel. By using Discrete Dipole Approximation (DDA), plasmonic resonance enhanced light scattering has been calculated for spherical silver nanoparticles with diameters ranging from 15nm to 200nm. Optimum scattering wavelength is specified for the nanoparticles in two media: water and air. The diffraction-limited plasmonic resonance enhanced images of silver nanoparticles at different diameters have been recorded and analyzed. By using standard PIV techniques, the velocity profile within the micro channel has been determined from the images.

  7. Fano coil-type resonances: a plasmonic tool for magnetic field enhancement (Conference Presentation)

    Science.gov (United States)

    Panaro, Simone; Proietti Zaccaria, Remo; Toma, Andrea

    2016-09-01

    Spintronics and spin-based technology rely on the ultra-fast unbalance of the electronic spin population in quite localized spatial regions. However, as a matter of fact, the low susceptibility of conventional materials at high frequencies strongly limits these phenomena, rendering the efficiency of magnetically active devices insufficient for application purposes. Among the possible strategies which can be envisaged, plasmonics offers a direct approach to increase the effect of local electronic unbalancing processes. By confining and enhancing free radiation in nm-size spatial regions, plasmonic nano-assemblies have demonstrated to support very intense electric and magnetic hot-spots. In particular, very recent studies have proven the fine control of magnetic fields in Fano resonance condition. The near-field-induced out-of-phase oscillation of localized surface plasmons has manifested itself with the arising of magnetic sub-diffractive hot-spots. Here, we show how this effect can be further boosted in the mid-infrared regime via the introduction of higher order plasmonic modes. The investigated system, namely Moon Trimer Resonator, combines the high efficiency of a strongly coupled nano-assembly in Fano interferential condition with the elevated tunability of the quadrupolar resonance supported by a moon-like geometry. The fine control of the apical gap in this unique nanostructure, characterizes a plasmonic device able to tune its resonance without any consequence on the magnetic hot-spot size, thus enabling an efficient squeezing in the infrared.

  8. Fano coil-type resonances: a plasmonic tool for the magnetic field manipulation (Conference Presentation)

    Science.gov (United States)

    Panaro, Simone; Proietti Zaccaria, Remo; Toma, Andrea

    2017-02-01

    Spintronics and spin-based technology rely on the ultra-fast unbalance of the electronic spin population in quite localized spatial regions. However, as a matter of fact, the low susceptibility of conventional materials at high frequencies strongly limits these phenomena, rendering the efficiency of magnetically active devices insufficient for application purposes. Among the possible strategies which can be envisaged, plasmonics offers a direct approach to increase the effect of local electronic unbalancing processes. By confining and enhancing free radiation in nm-size spatial regions, plasmonic nano-assemblies have demonstrated to support very intense electric and magnetic hot-spots. In particular, very recent studies have proven the fine control of magnetic fields in Fano resonance condition. The near-field-induced out-of-phase oscillation of localized surface plasmons has manifested itself with the arising of magnetic sub-diffractive hot-spots. Here, we show how this effect can be further boosted in the mid-infrared regime via the introduction of higher order plasmonic modes. The investigated system, namely Moon Trimer Resonator (MTR), combines the high efficiency of a strongly coupled nano-assembly in Fano interferential condition with the elevated tunability of the quadrupolar resonance supported by a moon-like geometry. The fine control of the apical gap in this unique nanostructure, characterizes a plasmonic device able to tune its resonance without any consequence on the magnetic hot-spot size, thus enabling an efficient squeezing in the infrared.

  9. Fano Resonance Based on Metal-Insulator-Metal Waveguide-Coupled Double Rectangular Cavities for Plasmonic Nanosensors

    Directory of Open Access Journals (Sweden)

    Zhidong Zhang

    2016-05-01

    Full Text Available A refractive index sensor based on metal-insulator-metal (MIM waveguides coupled double rectangular cavities is proposed and investigated numerically using the finite element method (FEM. The transmission properties and refractive index sensitivity of various configurations of the sensor are systematically investigated. An asymmetric Fano resonance lineshape is observed in the transmission spectra of the sensor, which is induced by the interference between a broad resonance mode in one rectangular and a narrow one in the other. The effect of various structural parameters on the Fano resonance and the refractive index sensitivity of the system based on Fano resonance is investigated. The proposed plasmonic refractive index sensor shows a maximum sensitivity of 596 nm/RIU.

  10. Handheld Chem/Biosensor Using Extreme Conformational Changes in Designed Binding Proteins to Enhance Surface Plasmon Resonance (SPR)

    Science.gov (United States)

    2016-04-01

    detection system for chemical and biological toxins . Surface Plasmon Resonance (SPR), protein design, protein engineering, supercharged protein ...chemical and biological toxins . Keywords: Surface Plasmon Resonance (SPR), protein design, protein engineering, supercharged protein , metamaterials...even this small index change, should be capable of detecting larger target molecules, such as proteins or even viral or bacterial pathogens, which

  11. Near-field coupling and resonant cavity modes in plasmonic nanorod metamaterials.

    Science.gov (United States)

    Song, Haojie; Zhang, Junxi; Fei, Guangtao; Wang, Junfeng; Jiang, Kang; Wang, Pei; Lu, Yonghua; Iorsh, Ivan; Xu, Wei; Jia, Junhui; Zhang, Lide; Kivshar, Yuri S; Zhang, Lin

    2016-10-14

    Plasmonic resonant cavities are capable of confining light at the nanoscale, resulting in both enhanced local electromagnetic fields and lower mode volumes. However, conventional plasmonic resonant cavities possess large Ohmic losses at metal-dielectric interfaces. Plasmonic near-field coupling plays a key role in a design of photonic components based on the resonant cavities because of the possibility to reduce losses. Here, we study the plasmonic near-field coupling in the silver nanorod metamaterials treated as resonant nanostructured optical cavities. Reflectance measurements reveal the existence of multiple resonance modes of the nanorod metamaterials, which is consistent with our theoretical analysis. Furthermore, our numerical simulations show that the electric field at the longitudinal resonances forms standing waves in the nanocavities due to the near-field coupling between the adjacent nanorods, and a new hybrid mode emerges due to a coupling between nanorods and a gold-film substrate. We demonstrate that this coupling can be controlled by changing the gap between the silver nanorod array and gold substrate.

  12. Near-field coupling and resonant cavity modes in plasmonic nanorod metamaterials

    Science.gov (United States)

    Song, Haojie; Zhang, Junxi; Fei, Guangtao; Wang, Junfeng; Jiang, Kang; Wang, Pei; Lu, Yonghua; Iorsh, Ivan; Xu, Wei; Jia, Junhui; Zhang, Lide; Kivshar, Yuri S.; Zhang, Lin

    2016-10-01

    Plasmonic resonant cavities are capable of confining light at the nanoscale, resulting in both enhanced local electromagnetic fields and lower mode volumes. However, conventional plasmonic resonant cavities possess large Ohmic losses at metal-dielectric interfaces. Plasmonic near-field coupling plays a key role in a design of photonic components based on the resonant cavities because of the possibility to reduce losses. Here, we study the plasmonic near-field coupling in the silver nanorod metamaterials treated as resonant nanostructured optical cavities. Reflectance measurements reveal the existence of multiple resonance modes of the nanorod metamaterials, which is consistent with our theoretical analysis. Furthermore, our numerical simulations show that the electric field at the longitudinal resonances forms standing waves in the nanocavities due to the near-field coupling between the adjacent nanorods, and a new hybrid mode emerges due to a coupling between nanorods and a gold-film substrate. We demonstrate that this coupling can be controlled by changing the gap between the silver nanorod array and gold substrate.

  13. Plasmonic properties of nanoparticle-film systems and periodic nanoparticle arrays

    Science.gov (United States)

    Le, Fei

    In this thesis we perform theoretical investigations on the optical properties of geometrically infinite metallic nano-structures such as nanoparticle/film systems and periodic nanoparticle arrays. We apply both Plasmon Hybridization (PH) and Finite-Difference Time-Domain (FDTD) methods and we obtain quantitative agreement with experimental measurements as well as other theoretical methods such as Mie Theory and Finite Element simulation. For the nanoparticle over film structure, our research shows that the plasmonic interaction between the nanoparticle and the film is an electromagnetic analogue of the spinless Anderson-Fano model, which was used to describe the interaction of a localized electronic state with a continuous band of electronic states. Three characteristic regimes of the model are realized as the energy of the nanoparticle plasmon resonance lies above, within, or below the energy band of the surface plasmon state. These three interaction regimes are controlled by the film thickness. In the thin film limit, the plasmonic coupling between the nanoshell and the film induces a low-energy virtual state (VS) mainly composed of delocalized film, which can be further tuned as the aspect ratio of the nanoshell changes. The calculations are found to agree well with experimental measurements. Using FDTD method, we show that the electromagnetic field enhancement induced by the VS in the thin film limit can be very large and the nanoparticle/film system could serve as an ideal substrate for Surface Enhanced Raman Spectroscopy (SERS) and Tip Enhanced Raman Spectroscopy (TERS). The plasmonic properties of nanoparticle arrays are investigated using FDTD with Periodic Boundary Conditions (PBC). Our research shows that 2D hexagonal (hcp) nanoshell arrays possess ideal properties as a substrate that combines SERS and Surface Enhanced Infrared Absorption (SEIRA), with large electric field enhancements at the same spatial locations in the structure. With small

  14. Near-Infrared Localized Surface Plasmon Resonances Arising from Free Carriers in Doped Quantum Dots

    Energy Technology Data Exchange (ETDEWEB)

    Jain, Prashant K.; Luther, Joey; Ewers, Trevor; Alivisatos, A. Paul

    2010-10-12

    Quantum confinement of electronic wavefunctions in semiconductor quantum dots (QDs) yields discrete atom-like and tunable electronic levels, thereby allowing the engineering of excitation and emission spectra. Metal nanoparticles, on the other hand, display strong resonant interactions with light from localized surface plasmon resonance (LSPR) oscillations of free carriers, resulting in enhanced and geometrically tunable absorption and scattering resonances. The complementary attributes of these nanostructures lends strong interest toward integration into hybrid nanostructures to explore enhanced properties or the emergence of unique attributes arising from their interaction. However, the physicochemical interface between the two components can be limiting for energy transfer and synergistic coupling within such a hybrid nanostructure. Therefore, it is advantageous to realize both attributes, i.e., LSPRs and quantum confinement within the same nanostructure. Here, we describe well-defined LSPRs arising from p-type carriers in vacancy-doped semiconductor quantum dots. This opens up possibilities for light harvesting, non-linear optics, optical sensing and manipulation of solid-state processes in single nanocrystals.

  15. A surface plasmon resonance immunosensor for detecting a dioxin precursor using a gold binding polypeptide

    DEFF Research Database (Denmark)

    Soh, N; Tokuda, T.; Watanabe, T.

    2003-01-01

    A surface plasmon resonance (SPR) based biosensor was developed for monitoring 2,4-dichlorophenol, a known dioxin precursor, using an indirect competitive immunoassay. The SPR sensor was fabricated by immobilizing a gold-thin layer on the surface of an SPR sensor chip with an anti-(2,4-dichloroph......A surface plasmon resonance (SPR) based biosensor was developed for monitoring 2,4-dichlorophenol, a known dioxin precursor, using an indirect competitive immunoassay. The SPR sensor was fabricated by immobilizing a gold-thin layer on the surface of an SPR sensor chip with an anti-(2...

  16. Plasmonic resonance scattering from silver nanowire illuminated by tightly focused singular beam.

    Science.gov (United States)

    Normatov, Alexander; Spektor, Boris; Leviatan, Yehuda; Shamir, Joseph

    2010-08-15

    We investigate scattering features of tightly focused singular beams by placing a cylindrical nanowire in the vicinity of a line phase singularity. Applying an illumination wavelength corresponding to silver cylinder plasmonic resonance, we compare the scattering response with that of a perfect conductor. The rigorous modeling employs a 2D version of the Richards-Wolf focusing method and the source model technique. It is found that a cylinder with a plasmonic resonance produces a strong scattering response by deflecting the power flow toward the optical singularity region, where otherwise the power approaches zero.

  17. Investigation of Real-Time Photorepair Activity on DNA via Surface Plasmon Resonance

    OpenAIRE

    2012-01-01

    4/24/2014 PLOS ONE: Investigation of Real-Time Photorepair Activity on DNA via Surface Plasmon Resonance http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0044392 1/9 Published: August 29, 2012 DOI: 10.1371/journal.pone.0044392 Investigation of Real-Time Photorepair Activity on DNA via Surface Plasmon Resonance Rıza Kizilel , Enis Demir, Selimcan Azizoglu, Hande Asımgi, Ibrahim Halil Kavakli , Seda Kizilel Corrections 25 Oct 2012: Kizilel R, Demir E, Aziz...

  18. Brightening gold nanoparticles: new sensing approach based on plasmon resonance energy transfer.

    Science.gov (United States)

    Shi, Lei; Jing, Chao; Gu, Zhen; Long, Yi-Tao

    2015-05-11

    Scattering recovered plasmonic resonance energy transfer (SR-PRET) was reported by blocking the plasmon resonance energy transfer (PRET) from gold nanoparticle (GNP) to the adsorbed molecules (RdBS). Due to the selective cleavage of the Si-O bond by F- ions, the quenching is switched off causing an increase in the brightness of the GNPs,detected using dark-field microscopy (DFM) were brightened. This method was successfully applied to the determination of fluoride ions in water. The SR-PRET provides a potential approach for a vitro/vivo sensing with high sensitivity and selectivity.

  19. Phase effects in guided mode resonances II: measuring the angular phase of a surface plasmon polariton

    Science.gov (United States)

    Theisen, M. J.; Brown, T. G.

    2015-02-01

    We show how the phase of a resonant interaction between a focused beam and a guided mode can be directly observed in a pupil imaging experiment, in which the irradiance leaving the pupil of a standard microscope is relayed to an image sensor through a combination Wollaston prism, calcite beam splitter and polarizer. We apply the method to the observation of a surface plasmon polariton resonance excited in a corrugated silver film fabricated using electron beam lithography. We discuss how this particular imaging configuration could be adapted for applications in plasmonic optical sensing.

  20. Forty-Four Pass Fibre Optic Loop for Improving the Sensitivity of Surface Plasmon Resonance Sensors

    CERN Document Server

    Su, Chin B

    2007-01-01

    A forty-four pass fibre optic surface plasmon resonance sensor that enhances detection sensitivity according to the number of passes is demonstrated for the first time. The technique employs a fibre optic recirculation loop that passes the detection spot forty- four times, thus enhancing sensitivity by a factor of forty-four. Presently, the total number of passes is limited by the onset of lasing action of the recirculation loop. This technique offers a significant sensitivity improvement for various types of plasmon resonance sensors that may be used in chemical and biomolecule detections.

  1. Plasmonic properties of metal nanoislands: surface integral equations approach

    Science.gov (United States)

    Scherbak, S. A.; Lipovskii, A. A.

    2016-08-01

    The surface integral equations method is used to analyse the surface plasmon resonance position in a metal island film formed by non-interacting axisymmetrical prolate/oblate hemispheroids placed on a dielectric substrate. The approach is verified via the comparison of results obtained for a hemisphere on a substrate with the ones obtained using the multipole expansion method. The preference of the integral equations method is in obtaining a simple final analytical expression for a particle polarizability in which any dielectric function of a metal can be substituted. Such simple formulae for the hemispherical particle on the substrate and calculated dependences of the hemispheroid resonant wavelength on its aspect ratio are presented.

  2. Tailoring the plasmonic whispering gallery modes of a metal-coated resonator for potential application as a refractometric sensor.

    Science.gov (United States)

    Guo, Chang-Lei; Che, Kai-Jun; Gu, Guo-Qiang; Cai, Guo-Xiong; Cai, Zhi-Ping; Xu, Hui-Ying

    2015-02-20

    Plasmonic whispering gallery (WG) modes confined in metal-coated resonators are theoretically investigated by electromagnetic analyses. The resonance can be tuned from internal surface plasmonic WG modes to the hybrid state of the plasmonic mode by an introduced isolation layer. As the coated metal is reduced in size, the optical resonance is shifted out by the mode coupling of the internal and external surface plasmonic WG modes. Based on the optical leak of the plasmonic WG mode, the optical influences led by the surroundings with a variable refractive index are considered. Device performance criteria such as optical power leak, resonant wavelength shift, and threshold gain are studied. Full wave simulations are also employed and the results present good consistency with analytic solutions. The metal-coated resonator assisted by an active material is expected to provide promising performance as a refractometric sensor.

  3. Near- and far-field properties of plasmonic oligomers under radially and azimuthally polarized light excitation.

    Science.gov (United States)

    Yanai, Avner; Grajower, Meir; Lerman, Gilad M; Hentschel, Mario; Giessen, Harald; Levy, Uriel

    2014-05-27

    We present a comprehensive experimental and theoretical study on the near- and far-field properties of plasmonic oligomers using radially and azimuthally polarized excitation. These unconventional polarization states are perfectly matched to the high spatial symmetry of the oligomers and thus allow for the excitation of some of the highly symmetric eigenmodes of the structures, which cannot be excited by linearly polarized light. In particular, we study hexamer and heptamer structures and strikingly find very similar optical responses, as well as the absence of a Fano resonance. Furthermore, we investigate the near-field distributions of the oligomers using near-field scanning optical microscopy (NSOM). We observe significantly enhanced near-fields, which arise from efficient excitation of the highly symmetric eigenmodes by the radially and azimuthally polarized light fields. Our study opens up possibilities for tailored light-matter interaction, combining the design freedom of complex plasmonic structures with the remarkable properties of radially and azimuthally polarized light fields.

  4. Unconventional Fano effect and off-resonance field enhancement in plasmonic coated spheres

    CERN Document Server

    Arruda, Tiago J; Pinheiro, Felipe A

    2013-01-01

    We investigate light scattering by coated spheres composed of a dispersive plasmonic core and a dielectric shell. By writing the absorption cross-section in terms of the internal electromagnetic fields, we demonstrate it is an observable sensitive to interferences that ultimately lead to the Fano effect. Specially, we show that unconventional Fano resonances, recently discovered for homogeneous spheres with large dielectric permittivities, can also occur for metallic spheres coated with single dielectric layers. These resonances arise from the interference between two electromagnetic modes with the same multipole moment inside the shell and not from interactions between various plasmon modes of different layers of the particle. In contrast to the case of homogeneous spheres, unconventional Fano resonances in coated spheres exist even in the Rayleigh limit. These resonances can induce an off-resonance field enhancement, which is approximately one order of magnitude larger than the one achieved with conventiona...

  5. Active Multiple Plasmon-Induced Transparency with Graphene Sheets Resonators in Mid-Infrared Frequencies

    Directory of Open Access Journals (Sweden)

    Jicheng Wang

    2016-01-01

    Full Text Available A multiple plasmon-induced transparency (PIT device operated in the mid-infrared region has been proposed. The designed model is comprised of one graphene ribbon as main waveguide and two narrow graphene sheets resonators. The phase coupling between two graphene resonators has been investigated. The multimode PIT resonances have been found in both cases and can be dynamically tuned via varying the chemical potential of graphene resonators without optimizing its geometric parameters. In addition, this structure can get multiple PIT effect by equipping extra two sheets on the symmetric positions of graphene waveguide. The simulation results based on finite element method (FEM are in good agreement with the resonance theory. This work may pave new way for graphene-based thermal plasmonic devices applications.

  6. Surface plasmon-polariton resonance at diffraction of THz radiation on semiconductor gratings

    CERN Document Server

    Spevak, I S; Gavrikov, V K; Shulga, V M; Feng, J; Sun, H B; Kamenev, Yu E; Kats, A V

    2013-01-01

    Resonance diffraction of THz HCN laser radiation on a semiconductor (InSb) grating is studied both experimentally and theoretically. The specular reflectivity suppression due to the resonance excitation of the THz surface plasmon-polariton is observed on a pure semiconductor grating and on semiconductor gratings covered with a thin striped layer of the residual photoresist. Presence of a thin dielectric layer on the grating surface leads to the shift and widening of the plasmon-polariton resonance. A simple analytical theory of the resonance diffraction on a shallow grating covered with a dielectric layer is presented. Its results are in a good accordance with the experimental data. Analytical expressions for the resonance shift and broadening can be useful for sensing data interpretation.

  7. Double-Slot Hybrid Plasmonic Ring Resonator Used for Optical Sensors and Modulators

    Directory of Open Access Journals (Sweden)

    Xu Sun

    2015-11-01

    Full Text Available An ultra-high sensitivity double-slot hybrid plasmonic (DSHP ring resonator, used for optical sensors and modulators, is developed. Due to high index contrast, as well as plasmonic enhancement, a considerable part of the optical energy is concentrated in the narrow slots between Si and plasmonic materials (silver is used in this paper, which leads to high sensitivity to the infiltrating materials. By partial opening of the outer plasmonic circular sheet of the DSHP ring, a conventional side-coupled silicon on insulator (SOI bus waveguide can be used. Experimental results demonstrate ultra-high sensitivity (687.5 nm/RIU of the developed DSHP ring resonator, which is about five-times higher than for the conventional Si ring with the same geometry. Further discussions show that a very low detection limit (5.37 × 10−6 RIU can be achieved after loaded Q factor modifications. In addition, the plasmonic metal structures offer also the way to process optical and electronic signals along the same hybrid plasmonic circuits with small capacitance (~0.275 fF and large electric field, which leads to possible applications in compact high-efficiency electro-optic modulators, where no extra electrodes for electronic signals are required.

  8. Multipitched Diffraction Gratings for Surface Plasmon Resonance-Enhanced Infrared Reflection Absorption Spectroscopy.

    Science.gov (United States)

    Petefish, Joseph W; Hillier, Andrew C

    2015-11-03

    We demonstrate the application of metal-coated diffraction gratings possessing multiple simultaneous pitch values for surface enhanced infrared absorption (SEIRA) spectroscopy. SEIRA increases the magnitude of vibrational signals in infrared measurements by one of several mechanisms, most frequently involving the enhanced electric field associated with surface plasmon resonance (SPR). While the majority of SEIRA applications to date have employed nanoparticle-based plasmonic systems, recent advances have shown how various metals and structures lead to similar signal enhancement. Recently, diffraction grating couplers have been demonstrated as a highly tunable platform for SEIRA. Indeed, gratings are an experimentally advantageous platform due to the inherently tunable nature of surface plasmon excitation at these surfaces since both the grating pitch and incident angle can be used to modify the spectral location of the plasmon resonance. In this work, we use laser interference lithography (LIL) to fabricate gratings possessing multiple pitch values by subjecting photoresist-coated glass slides to repetitive exposures at varying orientations. After metal coating, these gratings produced multiple, simultaneous plasmon peaks associated with the multipitched surface, as identified by infrared reflectance measurements. These plasmon peaks could then be coupled to vibrational modes in thin films to provide localized enhancement of infrared signals. We demonstrate the flexibility and tunability of this platform for signal enhancement. It is anticipated that, with further refinement, this approach might be used as a general platform for broadband enhancement of infrared spectroscopy.

  9. Size dependence of multipolar plasmon resonance frequencies and damping rates in simple metal spherical nanoparticles

    OpenAIRE

    2008-01-01

    Multipolar plasmon oscillation frequencies and corresponding damping rates for nanospheres formed of the simplest free-electron metals are studied. The possibility of controlling plasmon features by choosing the size and dielectric properties of the sphere surroundings is discussed. Optical properties of the studied metals are described within the Drude-Sommerfeld model of the dielectric function with effective parameters acounting for the contribution of conduction electrons and of interband...

  10. Thin SnOx films for surface plasmon resonance enhanced ellipsometric gas sensing (SPREE).

    Science.gov (United States)

    Fischer, Daniel; Hertwig, Andreas; Beck, Uwe; Lohse, Volkmar; Negendank, Detlef; Kormunda, Martin; Esser, Norbert

    2017-01-01

    Background: Gas sensors are very important in several fields like gas monitoring, safety and environmental applications. In this approach, a new gas sensing concept is investigated which combines the powerful adsorption probability of metal oxide conductive sensors (MOS) with an optical ellipsometric readout. This concept shows promising results to solve the problems of cross sensitivity of the MOS concept. Results: Undoped tin oxide (SnOx) and iron doped tin oxide (Fe:SnOx) thin add-on films were prepared by magnetron sputtering on the top of the actual surface plasmon resonance (SPR) sensing gold layer. The films were tested for their sensitivity to several gas species in the surface plasmon resonance enhanced (SPREE) gas measurement. It was found that the undoped tin oxide (SnOx) shows higher sensitivities to propane (C3H8) then to carbon monoxide (CO). By using Fe:SnOx, this relation is inverted. This behavior was explained by a change of the amount of binding sites for CO in the layer due to this iron doping. For hydrogen (H2) no such relation was found but the sensing ability was identical for both layer materials. This observation was related to a different sensing mechanism for H2 which is driven by the diffusion into the layer instead of adsorption on the surface. Conclusion: The gas sensing selectivity can be enhanced by tuning the properties of the thin film overcoating. A relation of the binding sites in the doped and undoped SnOx films and the gas sensing abilities for CO and C3H8 was found. This could open the path for optimized gas sensing devices with different coated SPREE sensors.

  11. Radiation-Suppressed plasmonic open resonators designed by nonmagnetic transformation optics

    Science.gov (United States)

    Xu, Hongyi; Wang, Xingjue; Yu, Tianyuan; Sun, Handong; Zhang, Baile

    2012-01-01

    How to confine light energy associated with surface plasmon polaritons (SPPs) in a physical space with minimal radiation loss whereas creating maximum interacting section with surrounding environment is of particular interest in plasmonic optics. By virtue of transformation optics, we propose a design method of forming a polygonal surface-plasmonic resonator in fully open structures by applying the nonmagnetic affine transformation optics strategy. The radiation loss can be suppressed because SPPs that propagate in the designed open structures will be deceived as if they were propagating on a flat metal/dielectric interface without radiation. Because of the nonmagnetic nature of the transformation strategy, this design can be implemented with dielectric materials available in nature. An experimentally verifiable model is subsequently proposed for future experimental demonstration. Our design may find potential applications in omnidirectional sensing, light harvesting, energy storage and plasmonic lasing. PMID:23136641

  12. Scattering and Extinction Torques: How Plasmon Resonances Affect the Orientation Behavior of a Nanorod in Linearly Polarized Light.

    Science.gov (United States)

    Xu, Xiaohao; Cheng, Chang; Zhang, Yao; Lei, Hongxiang; Li, Baojun

    2016-01-21

    Linearly polarized light can exert an orienting torque on plasmonic nanorods. The torque direction has generally been considered to change when the light wavelength passes through a plasmon longitudinal resonance. Here, we use the Maxwell stress tensor to evaluate this torque in general terms. According to distinct light-matter interaction processes, the total torque is decomposed into scattering and extinction torques. The scattering torque tends to orient plasmonic nanorods parallel to the light polarization, independent of the choice of light wavelength. The direction of the extinction torque is not only closely tied to the excitation of plasmon resonance but also depends on the specific plasmon mode around which the light wavelength is tuned. Our findings show that the conventional wisdom that simply associates the total torque with the plasmon longitudinal resonances needs to be replaced with an understanding based on the different torque components and the details of spectral distribution.

  13. Plasmon resonant gold-coated liposomes for spectrally coded content release

    Science.gov (United States)

    Leung, Sarah J.; Troutman, Timothy S.; Romanowski, Marek

    2009-02-01

    We have recently introduced liposome-supported plasmon resonant gold nanoshells (Troutman et al., Adv. Mater. 2008, 20, 2604-2608). These plasmon resonant gold-coated liposomes are degradable into components of a size compatible with renal clearance, potentially enabling their use as multifunctional agents in applications in nanomedicine, including imaging, diagnostics, therapy, and drug delivery. The present research demonstrates that laser illumination at the wavelength matching the plasmon resonance band of a gold-coated liposome leads to the rapid release of encapsulated substances, which can include therapeutic and diagnostic agents. Leakage of encapsulated contents is monitored through the release of self-quenched fluorescein, which provides an increase in fluorescence emission upon release. Moreover, the resonant peak of these gold-coated liposomes is spectrally tunable in the near infrared range by varying the concentration of gold deposited on the surface of liposomes. Varying the plasmon resonant wavelengths of gold-coated liposomes can provide a method for spectrally-coding their light-mediated content release, so that the release event is initiated by the specific wavelength of light used to illuminate the liposomes. The development of spectrally-coded release can find applications in controlled delivery of multiple agents to support complex diagnostic tests and therapeutic interventions.

  14. Rational design of on-chip refractive index sensors based on lattice plasmon resonances (Presentation Recording)

    Science.gov (United States)

    Lin, Linhan; Zheng, Yuebing

    2015-08-01

    Lattice plasmon resonances (LPRs), which originate from the plasmonic-photonic coupling in gold or silver nanoparticle arrays, possess ultra-narrow linewidth by suppressing the radiative damping and provide the possibility to develop the plasmonic sensors with high figure of merit (FOM). However, the plasmonic-photonic coupling is greatly suppressed when the nanoparticles are immobilized on substrates because the diffraction orders are cut off at the nanoparticle-substrate interfaces. Here, we develop the rational design of LPR structures for the high-performance, on-chip plasmonic sensors based on both orthogonal and parallel coupling. Our finite-difference time-domain simulations in the core/shell SiO2/Au nanocylinder arrays (NCAs) reveal that new modes of localized surface plasmon resonances (LSPRs) show up when the aspect ratio of the NCAs is increased. The height-induced LSPRs couple with the superstrate diffraction orders to generate the robust LPRs in asymmetric environment. The high wavelength sensitivity and narrow linewidth in these LPRs lead to the plasmonic sensors with high FOM and high signal-to-noise ratio (SNR). Wide working wavelengths from visible to near-infrared are also achieved by tuning the parameters of the NCAs. Moreover, the wide detection range of refractive index is obtained in the parallel LPR structure. The electromagnetic field distributions in the NCAs demonstrate the height-enabled tunability of the plasmonic "hot spots" at the sub-nanoparticles resolution and the coupling between these "hot spots" with the superstrate diffraction waves, which are responsible for the high performance LPRs-based on-chip refractive index sensors.

  15. Guided-mode-resonance coupled localized surface plasmons for dually resonance enhanced Raman scattering sensing

    Science.gov (United States)

    Wang, Zheng; Liu, Chao; Li, Erwen; Chakravarty, Swapnajit; Xu, Xiaochuan; Wang, Alan X.; Fan, D. L.; Chen, Ray T.

    2017-02-01

    Raman scattering spectroscopy is a unique tool to probe vibrational, rotational, and other low-frequency modes of a molecular system and therefore could be utilized to identify chemistry and quantity of molecules. However, the ultralow efficient Raman scattering, which is only 1/109 1/1014 of the excitation light due to the small Raman scattering cross-sections of molecules, have significantly hindered its development in practical sensing applications. The discovery of surface-enhanced Raman scattering (SERS) in the 1970s and the significant progress in nanofabrication technique, provide a promising solution to overcome the inherent issues of Raman spectroscopy. It is found that In the vicinity of nanoparticles and their junctions, the Raman signals of molecules can be significantly improved by an enhancement factor as high as 1010, due to the ultrahigh electric field generated by the localized surface plasmons resonance (LSPR), where the intensity of Raman scattering is proportional to the |E|4. In this work, we propose and demonstrate a new approach combining LSPR from nanocapsules with densely assembled silver nanoparticles (NC-AgNPs) and guidemode- resonance (GMR) from dielectric photonic crystal slabs (PCSs) for SERS substrates with robustly high performance.

  16. Refractive index dispersion of swift heavy ion irradiated BFO thin films using Surface Plasmon Resonance technique

    Science.gov (United States)

    Paliwal, Ayushi; Sharma, Savita; Tomar, Monika; Singh, Fouran; Gupta, Vinay

    2016-07-01

    Swift heavy ion irradiation (SHI) is an effective technique to induce defects for possible modifications in the material properties. There is growing interest in studying the optical properties of multiferroic BiFeO3 (BFO) thin films for optoelectronic applications. In the present work, BFO thin films were prepared by sol-gel spin coating technique and were irradiated using the 15 UD Pelletron accelerator with 100 MeV Au9+ ions at a fluence of 1 × 1012 ions cm-2. The as-grown films became rough and porous on ion irradiation. Surface Plasmon Resonance (SPR) technique has been identified as a highly sensitive and powerful technique for studying the optical properties of a dielectric material. Optical properties of BFO thin films, before and after irradiation were studied using SPR technique in Otto configuration. Refractive index is found to be decreasing from 2.27 to 2.14 on ion irradiation at a wavelength of 633 nm. Refractive index dispersion of BFO thin film (from 405 nm to 633 nm) before and after ion radiation was examined.

  17. Development of a surface plasmon resonance biosensing approach for the rapid detection of porcine circovirus type2 in sample solutions.

    Directory of Open Access Journals (Sweden)

    Jiandong Hu

    Full Text Available A sensitive and label-free analytical approach for the detection of porcine circovirus type 2 (PCV2 instead of PCV2 antibody in serum sample was systematically investigated in this research based on surface plasmon resonance (SPR with an establishment of special molecular identification membrane. The experimental device for constructing the biosensing analyzer is composed of an integrated biosensor, a home-made microfluidic module, and an electrical control circuit incorporated with a photoelectric converter. In order to detect the PCV2 using the surface plasmon resonance immunoassay, the mercaptopropionic acid has been used to bind the Au film in advance through the known form of the strong S-Au covalent bonds formed by the chemical radical of the mercaptopropionic acid and the Au film. PCV2 antibodies were bonded with the mercaptopropionic acid by covalent -CO-NH- amide bonding. For the purpose of evaluating the performance of this approach, the known concentrations of PCV2 Cap protein of 10 µg/mL, 7.5 µg/mL, 5 µg/mL, 2.5 µg/mL, 1 µg/mL, and 0.5 µg/mL were prepared by diluting with PBS successively and then the delta response units (ΔRUs were measured individually. Using the data collected from the linear CCD array, the ΔRUs gave a linear response over a wide concentration range of standard known concentrations of PCV2 Cap protein with the R-Squared value of 0.99625. The theoretical limit of detection was calculated to be 0.04 µg/mL for the surface plasmon resonance biosensing approach. Correspondingly, the recovery rate ranged from 81.0% to 89.3% was obtained. In contrast to the PCV2 detection kits, this surface plasmon resonance biosensing system was validated through linearity, precision and recovery, which demonstrated that the surface plasmon resonance immunoassay is reliable and robust. It was concluded that the detection method which is associated with biomembrane properties is expected to contribute much to determine the PCV2

  18. Development of a surface plasmon resonance biosensing approach for the rapid detection of porcine circovirus type2 in sample solutions.

    Science.gov (United States)

    Hu, Jiandong; Wang, Tingting; Wang, Shun; Chen, Mingwen; Wang, Manping; Mu, Linying; Chen, Hongyin; Hu, Xinran; Liang, Hao; Zhu, Juanhua; Jiang, Min

    2014-01-01

    A sensitive and label-free analytical approach for the detection of porcine circovirus type 2 (PCV2) instead of PCV2 antibody in serum sample was systematically investigated in this research based on surface plasmon resonance (SPR) with an establishment of special molecular identification membrane. The experimental device for constructing the biosensing analyzer is composed of an integrated biosensor, a home-made microfluidic module, and an electrical control circuit incorporated with a photoelectric converter. In order to detect the PCV2 using the surface plasmon resonance immunoassay, the mercaptopropionic acid has been used to bind the Au film in advance through the known form of the strong S-Au covalent bonds formed by the chemical radical of the mercaptopropionic acid and the Au film. PCV2 antibodies were bonded with the mercaptopropionic acid by covalent -CO-NH- amide bonding. For the purpose of evaluating the performance of this approach, the known concentrations of PCV2 Cap protein of 10 µg/mL, 7.5 µg/mL, 5 µg/mL, 2.5 µg/mL, 1 µg/mL, and 0.5 µg/mL were prepared by diluting with PBS successively and then the delta response units (ΔRUs) were measured individually. Using the data collected from the linear CCD array, the ΔRUs gave a linear response over a wide concentration range of standard known concentrations of PCV2 Cap protein with the R-Squared value of 0.99625. The theoretical limit of detection was calculated to be 0.04 µg/mL for the surface plasmon resonance biosensing approach. Correspondingly, the recovery rate ranged from 81.0% to 89.3% was obtained. In contrast to the PCV2 detection kits, this surface plasmon resonance biosensing system was validated through linearity, precision and recovery, which demonstrated that the surface plasmon resonance immunoassay is reliable and robust. It was concluded that the detection method which is associated with biomembrane properties is expected to contribute much to determine the PCV2 in sample

  19. Magneto-optical response of Cu/NiFe/Cu nanostructure under surface plasmon resonance

    Science.gov (United States)

    Mahmoodi, S.; Moradi, M.; Mohseni, S. M.

    2016-12-01

    In this paper, we present theoretical and experimental studies about the surface plasmon resonance effects on the magneto-optical activity of Cu/NiFe/Cu nanostructures as a function of layers thickness and light incident angle. Device fabrication was done by an oblique deposition technique with RF magnetron sputtering to carefully cover fine step thickness variation of all constituted layers. Angular dependent transverse Kerr response of samples was measured in the Kretschmann configuration at a fixed wavelength of 632 nm. At an optimum layer thickness and incident angle, significant amplification of the transverse Kerr effect was observed. Enhancement in the transverse Kerr effect can be realized by hybridization of surface plasmon excitation and cavity resonance in the plasmonic nanostructure. Experimental results were in qualitative agreement with modeling based on the 4×4 transfer matrix formalism.

  20. Plasmon-Induced Resonant Energy Transfer: a coherent dipole-dipole coupling mechanism

    Science.gov (United States)

    Bristow, Alan D.; Cushing, Scott K.; Li, Jiangtian; Wu, Nianqiang

    Metal-insulator-semiconductor core-shell nanoparticles have been used to demonstrate a dipole-dipole coupling mechanism that is entirely dependent on the dephasing time of the localized plasmonic resonance. Consequently, the short-time scale of the plasmons leads to broad energy uncertainty that allows for excitation of charge carriers in the semiconductor via stimulation of photons with energies below the energy band gap. In addition, this coherent energy transfer process overcomes interfacial losses often associated with direct charge transfer. This work explores the efficiency of the energy transfer process, the dipole-dipole coupling strength with dipole separation, shell thickness and plasmonic resonance overlap. We demonstrate limits where the coherent nature of the coupling is switched off and charge transfer processes can dominate. Experiments are performed using transient absorption spectroscopy. Results are compared to calculations using a quantum master equation. These nanostructures show strong potential for improving solar light-harvesting for power and fuel generation.

  1. Optical magnetism and plasmonic Fano resonances in metal-insulator-metal oligomers.

    Science.gov (United States)

    Verre, R; Yang, Z J; Shegai, T; Käll, M

    2015-03-11

    The possibility of achieving optical magnetism at visible frequencies using plasmonic nanostructures has recently been a subject of great interest. The concept is based on designing structures that support plasmon modes with electron oscillation patterns that imitate current loops, that is, magnetic dipoles. However, the magnetic resonances are typically spectrally narrow, thereby limiting their applicability in, for example, metamaterial designs. We show that a significantly broader magnetic response can be realized in plasmonic pentamers constructed from metal-insulator-metal (MIM) sandwich particles. Each MIM unit acts as a magnetic meta-atom and the optical magnetism is rendered quasi-broadband through hybridization of the in-plane modes. We demonstrate that scattering spectra of individual MIM pentamers exhibit multiple Fano resonances and a broad subradiant spectral window that signals the magnetic interaction and a hierarchy of coupling effects in these intricate three-dimensional nanoparticle oligomers.

  2. Reflectors and resonators for high-k bulk Bloch plasmonic waves in multilayer hyperbolic metamaterials

    DEFF Research Database (Denmark)

    Zhukovsky, Sergei; Lavrinenko, Andrei

    2012-01-01

    We propose proof-of-concept designs of Bragg reflectors and Fabry-Pe´rot resonators for large wave vector waves (Bloch bulk plasmon polaritons) in multilayer metal-dielectric hyperbolic metamaterials. The designs are based on hybrid multilayers having both subwavelength and wavelength-scale struc......We propose proof-of-concept designs of Bragg reflectors and Fabry-Pe´rot resonators for large wave vector waves (Bloch bulk plasmon polaritons) in multilayer metal-dielectric hyperbolic metamaterials. The designs are based on hybrid multilayers having both subwavelength and wavelength......-scale structuring. This multiscale approach is shown to be a promising platform for using bulk plasmonic waves in complex multilayer metamaterials as a new kind of information carriers....

  3. Properties of infrared doped semiconductor Mie resonators (Presentation Recording)

    Science.gov (United States)

    Lewi, Tomer; Iyer, Prasad P.; Butakov, Nikita A.; Schuller, Jon A.

    2015-09-01

    Dielectric optical antenna resonators have recently emerged as a viable alternative to plasmonic resonators for metamaterials and nanophotonic devices, due to their ability to support multipolar Mie resonances with low losses. In this work, we experimentally investigate the mid-infrared Mie resonances in Si and Ge subwavelength spherical particles. In particular, we leverage the electronic and optical properties of these semiconductors in the mid-infrared range to design and tune Mie resonators through free-carrier refraction. Si and Ge semiconductor spheres of varying sizes of 0.5-4 μm were fabricated using femtosecond laser ablation. Using single particle infrared spectroscopy, we first demonstrate size-dependent Si and Ge Mie resonances spanning the entire mid-infrared (2-16 μm) spectral range. Subsequently we show that the Mie resonances can be tuned by varying material properties rather than size or geometry. We experimentally demonstrate doping-dependent resonance frequency shifts that follow simple Drude models of free-carrier refraction. We show that Ge particles exhibit a stronger doping dependence than Si due to the smaller effective mass of the free carriers. Using the unique size and doping dispersion of the electric and magnetic dipole modes, we identify and demonstrate a size regime where these modes are spectrally overlapping. We also demonstrate the emergence of plasmonic resonances for high doping levels and long wavelengths. These findings demonstrate the potential for tuning infrared semiconductor Mie resonances by optically or electrically modulating charge carrier densities, thus providing an excellent platform for tunable electromagnetic metamaterials.

  4. Engineered absorption enhancement and induced transparency in coupled molecular and plasmonic resonator systems.

    Science.gov (United States)

    Adato, Ronen; Artar, Alp; Erramilli, Shyamsunder; Altug, Hatice

    2013-06-12

    Coupled plasmonic resonators have become the subject of significant research interest in recent years as they provide a route to dramatically enhanced light-matter interactions. Often, the design of these coupled mode systems draws intuition and inspiration from analogies to atomic and molecular physics systems. In particular, they have been shown to mimic quantum interference effects, such as electromagnetically induced transparency (EIT) and Fano resonances. This analogy also been used to describe the surface-enhanced absorption effect where a plasmonic resonance is coupled to a weak molecular resonance. These important phenomena are typically described using simple driven harmonic (or linear) oscillators (i.e., mass-on-a-spring) coupled to each other. In this work, we demonstrate the importance of an essential interdependence between the rate at which the system can be driven by an external field and its damping rate through radiative loss. This link is required in systems exhibiting time-reversal symmetry and energy conservation. Not only does it ensure an accurate and physically consistent description of resonant systems but leads directly to interesting new effects. Significantly, we demonstrate this dependence to predict a transition between EIT and electromagnetically induced absorption that is solely a function of the ratio of the radiative to intrinsic loss rates in coupled resonator systems. Leveraging the temporal coupled mode theory, we introduce a unique and intuitive picture that accurately describes these effects in coupled plasmonic/molecular and fully plasmonic systems. We demonstrate our approach's key features and advantages analytically as well as experimentally through surface-enhanced absorption spectroscopy and plasmonic metamaterial applications.

  5. Controlled assembly and plasmonic properties of asymmetric core-satellite nanoassemblies.

    Science.gov (United States)

    Yoon, Jun Hee; Lim, Jonghui; Yoon, Sangwoon

    2012-08-28

    The assembly of noble metal nanoparticles offers an appealing means to control and enhance the plasmonic properties of nanostructures. However, making nanoassemblies with easily modifiable gap distances with high efficiency has been challenging. Here, we report a novel strategy to assemble gold nanoparticles (AuNPs) into Janus-type asymmetric core-satellite nanostructures. Markedly different desorption efficiency between large and small AuNPs in ethanol allows us to prepare the asymmetric core-satellite nanoassemblies in a dispersed colloidal state with near 100% purity. The resulting nanoassemblies have well-defined structures in which a core AuNP (51 nm) is covered by an average of 13 ± 3 satellite AuNPs (13 nm) with part of the core surfaces left unoccupied. Strong surface plasmon coupling is observed from these nanoassemblies as a result of the close proximity between the core and the satellites, which appears significantly red-shifted from the surface plasmon resonance frequencies of the constituting nanoparticles. The dependence of the surface plasmon coupling on a gap distance of less than 3 nm is systematically investigated by varying the length of the alkanedithiol linkers. The asymmetric core-satellite nanoassemblies also serve as an excellent surface-enhanced Raman scattering substrate with an enhancement factor of ~10(6). Finally, we demonstrate that the presented assembly method is extendible to the preparation of compositionally heterogeneous core-satellite nanoassemblies.

  6. Sensing (un)binding events via surface plasmons: effects of resonator geometry

    Science.gov (United States)

    Antosiewicz, Tomasz J.; Claudio, Virginia; Käll, Mikael

    2016-04-01

    The resonance conditions of localized surface plasmon resonances (LSPRs) can be perturbed in any number ways making plasmon nanoresonators viable tools in detection of e.g. phase changes, pH, gasses, and single molecules. Precise measurement via LSPR of molecular concentrations hinge on the ability to confidently count the number of molecules attached to a metal resonator and ideally to track binding and unbinding events in real-time. These two requirements make it necessary to rigorously quantify relations between the number of bound molecules and response of plasmonic sensors. This endeavor is hindered on the one hand by a spatially varying response of a given plasmonic nanosensor. On the other hand movement of molecules is determined by stochastic effects (Brownian motion) as well as deterministic flow, if present, in microfluidic channels. The combination of molecular dynamics and the electromagnetic response of the LSPR yield an uncertainty which is little understood and whose effect is often disregarded in quantitative sensing experiments. Using a combination of electromagnetic finite-difference time-domain (FDTD) calculations of the plasmon resonance peak shift of various metal nanosensors (disk, cone, rod, dimer) and stochastic diffusion-reaction simulations of biomolecular interactions on a sensor surface we clarify the interplay between position dependent binding probability and inhomogeneous sensitivity distribution. We show, how the statistical characteristics of the total signal upon molecular binding are determined. The proposed methodology is, in general, applicable to any sensor and any transduction mechanism, although the specifics of implementation will vary depending on circumstances. In this work we focus on elucidating how the interplay between electromagnetic and stochastic effects impacts the feasibility of employing particular shapes of plasmonic sensors for real-time monitoring of individual binding reactions or sensing low concentrations

  7. A reconfigurable subwavelength plasmonic fano nano-antenna based on split ring resonator

    Science.gov (United States)

    Hosseinbeig, Ahmad; Pirooj, Azadeh; Zarrabi, Ferdows B.

    2017-02-01

    In this article, a reconfigurable subwavelength plasmonic nano-antenna with Fano resonance effect is presented based on the dual ring structure. In order to achieve reconfigurable characteristics, the interaction of gold with graphene is studied. SiN substrate with refractive index of 1.98 and gold with Palik optical characteristic modified for metal layer are utilized in the design of the proposed nano-antenna. Simulations are performed by using CST Microwave Studio. The biasing effect on extinction cross section is studied for 0 to 0.8 eV. It is shown that the gap method is useful for exciting the Fano resonance in the dual ring nano-antenna and there is only a plasmonic resonance in the simple dual ring antenna. The proposed nano-antenna is useful for THz medical spectroscopy due to its simple design and the ability to control the second resonance frequency by changing the bias of the graphene.

  8. Linear and nonlinear optics of hybrid plasmon-exciton nanomaterials in the presence of overlapping resonances

    CERN Document Server

    Sukharev, Maxim; Pachter, Ruth

    2015-01-01

    We consider a hybrid plasmon-exciton system comprised of a resonant molecular subsystem and three Au wires supporting a dipole mode which can be coupled to a dark mode in controllable fashion by variation of a symmetry parameter. The physics of such a system under strong coupling conditions is examined in detail. It is shown that if two wires supporting the dark mode are covered with molecular layers the system exhibits four resonant modes for a strong coupling regime due to asymmetry and lifted degeneracy of the molecular state in this case, while upon having molecular aggregates covering the top wire with dipolar mode, three resonant modes appear. Pump-probe simulations are performed to scrutinize the quantum dynamics and find possible ways to control plasmon-exciton materials. It is demonstrated that one can design hybrid nanomaterials with highly pronounced Fano-type resonances when excited by femtosecond lasers.

  9. Studies on Interactions of Antibiotics with Serum Albumin by Surface Plasmon Resonance Biosensor

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Characterizing how chemical compounds binding to serum albumin is essential in evaluating drug candidates and is the focus of this study. A surface plasmon resonance biosensor developed in this laboratory was used to determine the binding constants of antibiotics with serum albumin. The binding constants of five antibiotics(azithromycin, spectinomycin, gentamycin, metacycline and kanamycin) with serum albumins were obtained.

  10. Surface plasmon resonance (SPR) detection of Staphylococcal Enterotoxin A in food samples

    Science.gov (United States)

    An automated and rapid method for detection of staphylococcal enterotoxins (SE) is needed. A sandwich assay was developed using a surface plasmon resonance (SPR) biosensor for detection of staphylococcal enterotoxin A (SEA) at subpicomolar concentration. Assay conditions were optimized for capturing...

  11. Thermal energy transfer by plasmon-resonant composite nanoparticles at pulse laser irradiation.

    Science.gov (United States)

    Avetisyan, Yuri A; Yakunin, Alexander N; Tuchin, Valery V

    2012-04-01

    Heating of composite plasmon-resonant nanoparticles (spherical gold nanoshells) under pulse laser illumination is considered. The numerical solution of the time-dependent heat conduction equation accounting for spatial inhomogeneities of absorbed laser radiation is performed. Important features of temperature kinetics and thermal flux inside nanoparticles are analyzed. Possible applications of the observed effects in nanotechnology and medicine are discussed.

  12. Improvement of the Specificity of Surface Plasmon Resonance with BSA-modified Chip

    Institute of Scientific and Technical Information of China (English)

    Li Hua CHEN

    2006-01-01

    A chip was modified with bovine serum albumin (BSA), then interaction between glutathione (GSH) immobilized on the top of BSA and glutathione-S-transferase (GST) was examined, using surface plasmon resonance (SPR). The SPR results showed that BSA-modified chip was effective not only in binding the target proteins but also in suppressing the nonspecific binding (NSB) of proteins.

  13. Normalization of quasinormal modes in leaky optical cavities and plasmonic resonators

    CERN Document Server

    Kristensen, Philip Trøst; Hughes, Stephen

    2015-01-01

    We discuss three formally different formulas for normalization of quasinormal modes currently in use for modeling optical cavities and plasmonic resonators and show that they are complementary and provide the same result. Regardless of the formula used for normalization, one can use the norm to define an effective mode volume for use in Purcell factor calculations.

  14. Rapid Determination of Phytophthora infestans sporangia Using a Surface Plasmon Resonance Immunosensor

    DEFF Research Database (Denmark)

    Skottrup, Peter; Nicolaisen, Mogens; Justesen, Annemarie Fejer

    2007-01-01

    Phytophthora infestans is the cause of late blight disease in potato and is an economically important pathogen worldwide. Early disease detection is important to implement disease control measures. In this study a surface plasmon resonance (SPR) immunosensor for detection of P. infestans sporangia...

  15. Development of a biosensor microarray towards food screening using imaging surface plasmon resonance

    NARCIS (Netherlands)

    Rebe, S.; Bremer, M.G.E.G.; Giesbers, M.; Norde, W.

    2008-01-01

    In this study we examined the possibilities of implementing direct and competitive immunoassay formats for small and large molecule detection on a microarray, using IBIS imaging surface plasmon resonance (iSPR) system. First, IBIS iSPR optics performance was evaluated. Using a glycerol calibration c

  16. Using a surface plasmon resonance biosensor for rapid detection of salmonella typhimurium in chicken carcass

    Science.gov (United States)

    Chicken is one of the most popular meat products in the world. Salmonella Typhimurium is a common foodborne pathogens associated with the processing of poultry. An optical Surface Plasmon Resonance (SPR) biosensor was sensitive to the presence of Salmonella Typhimurium in chicken carcass. The Spr...

  17. Detection of benzimidazole carbamates and amino metabolites in liver by surface plasmon resonance-biosensor

    Science.gov (United States)

    Two surface plasmon resonance (SPR) biosensor screening assays were developed and validated to detect 11 benzimidazole carbamate (BZT) and four amino-benzimidazole veterinary drug residues in liver tissue. The assays used polyclonal antibodies, raised in sheep, to detect BZTs and amino-benzimidazole...

  18. Rapid Determination of Phytophthora infestans sporangia Using a Surface Plasmon Resonance Immunosensor

    DEFF Research Database (Denmark)

    Skottrup, Peter Durand; Nicolaisen, Mogens; Justesen, Annemarie Fejer

    2007-01-01

    Phytophthora infestans is the cause of late blight disease in potato and is an economically important pathogen worldwide. Early disease detection is important to implement disease control measures. In this study a surface plasmon resonance (SPR) immunosensor for detection of P. infestans sporangi...

  19. Detection of Fungal Spores Using a Generic Surface Plasmon Resonance Immunoassay

    DEFF Research Database (Denmark)

    Skottrup, Peter Durand; Hearty, Stephen; Frøkiær, Hanne

    2007-01-01

    This paper describes a biosensor-based method for detection of fungal spores using Surface Plasmon Resonance (SPR). The approach involves the use of a mouse monoclonal antibody (Pst mAb8) and a SPR sensor for label-free detection of urediniospores from the model organism Puccinia striiformis f.sp...

  20. Detection of mycotoxins using imaging surface plasmon resonance (iSPR)

    Science.gov (United States)

    Significant progress has been made in the development of biosensors that can be used to detect mycotoxins. One technology that has been extensively tested is surface plasmon resonance (SPR). In 2003 a multi-toxin method was reported that detected aflatoxin B1 (AFB1), zearalenone (ZEA), fumonisin B1 ...

  1. The application of neoglycopeptides in the development of sensitive surface plasmon resonance-based biosensors

    NARCIS (Netherlands)

    Maljaars, C.E.P.; de Souza, A.C.; Halkes, K.M.; Upton, P.J.; Reeman, S.M.; André, S.; Gabius, H.-J.; McDonnell, M.B.; Kamerling, J.P.

    2008-01-01

    The development of a biosensor based on surface plasmon resonance is described for the detection of carbohydrate-binding proteins in solution on a Biacore 2000 instrument, using immobilized glycopeptides as ligands. Their selection was based on previous screenings of solid-phase glycopeptide

  2. The application of neoglycopeptides in the development of sensitive surface plasmon resonance-based biosensors

    NARCIS (Netherlands)

    Maljaars, C.E.P.; de Souza, A.C.; Halkes, K.M.; Upton, P.J.; Reeman, S.M.; André, S.; Gabius, H.-J.; McDonnell, M.B.; Kamerling, J.P.

    2008-01-01

    The development of a biosensor based on surface plasmon resonance is described for the detection of carbohydrate-binding proteins in solution on a Biacore 2000 instrument, using immobilized glycopeptides as ligands. Their selection was based on previous screenings of solid-phase glycopeptide librari

  3. A Surface Plasmon Resonance Immunosensor for Detection of urediniospores from Puccinia striiformis f. sp. tritici

    DEFF Research Database (Denmark)

    Skottrup, Peter; Hearty, Stephen; Frøkiær, Hanne;

    2006-01-01

    This study describes a generic biosensing principle for detection of fungal spores using surface plasmon resonance (SPR). The approach involves the use of a mouse monoclonal antibody (mAb) and a SPR sensor for label-free detection of the model organism Puccinia striiformis f.sp. tritici (Pst). We...

  4. Multiplex surface plasmon resonance imaging platform for label-free detection of foodborne pathogens

    Science.gov (United States)

    Salmonellae are among the leading causes of foodborne outbreaks in the United States, and more rapid and efficient detection methods are needed. Surface plasmon resonance imaging (SPRi) is an emerging optical technique, which allows for rapid and label-free screening of multiple targets simultaneous...

  5. Detection of egg yolk antibodies reflecting Salmonella enteritidis infections using a surface plasmon resonance biosensor

    NARCIS (Netherlands)

    Thomas, M.E.; Bouma, A.; Eerden, van E.; Landman, W.J.M.; Knapen, van F.; Stegeman, J.A.; Bergwerff, A.A.

    2006-01-01

    A surface plasmon resonance (SPR) biosensor assay was developed on the basis of a lipopolysaccharide antigen of Salmonella enterica serovar enteritidis (S. enterica serovar enteritidis) to detect egg yolk antibodies against S. enterica serovar enteritidis. This biosensor assay was compared to two co

  6. Nanopatterned submicron pores as a shield for nonspecific binding in surface plasmon resonance-based sensing

    NARCIS (Netherlands)

    Raz, Sabina Rebe; Marchesini, Gerardo R.; Bremer, Maria G. E. G.; Colpo, Pascal; Garcia, Cesar Pascual; Guidetti, Guido; Norde, Willem; Rossi, Francois

    2012-01-01

    We present a novel approach to tackle the most common drawback of using surface plasmon resonance for analyte screening in complex biological matrices - the nonspecific binding to the sensor chip surface. By using a perforated membrane supported by a polymeric gel structure at the evanescent wave pe

  7. Development of a biosensor microarray towards food screening, using imaging surface plasmon resonance

    NARCIS (Netherlands)

    Raz, Sabina Rebe; Bremer, Maria G. E. G.; Giesbers, Marcel; Norde, Willem

    2008-01-01

    In this study we examined the possibilities of implementing direct and competitive immunoassay formats for small and large molecule detection on a microarray, using IBIS imaging surface plasmon resonance (iSPR) system. First, IBIS iSPR optics performance was evaluated. Using a glycerol calibration c

  8. Quantifying protein-protein interactions in the ubiquitin pathway by surface plasmon resonance

    DEFF Research Database (Denmark)

    Hartmann-Petersen, Rasmus; Gordon, Colin

    2005-01-01

    The commercial availability of instruments, such as Biacore, that are capable of monitoring surface plasmon resonance (SPR) has greatly simplified the quantification of protein-protein interactions. Already, this technique has been used for some studies of the ubiquitin-proteasome system. Here we...

  9. Enhancing the gas sensitivity of surface plasmon resonance with a nanoporous silica matrix

    NARCIS (Netherlands)

    Berrier, A.; Offermans, P.; Cools, R.; Megen, B. van; Knoben, W.; Vecchi, G.; Rivas, J.G.; Crego-Calama, M.; Brongersma, S.H.

    2011-01-01

    The development of sensing schemes for the detection of health-threatening gases is an attractive subject for research towards novel integrated autonomous sensor systems. We report here on a novel way of sensing NO\\2 by surface plasmon resonance (SPR) using a gas-sensitive layer composed of

  10. Broadening of Plasmonic Resonance Due to Electron Collisions with Nanoparticle Boundary: а Quantum Mechanical Consideration

    DEFF Research Database (Denmark)

    Uskov, Alexander; Protsenko, Igor E.; Mortensen, N. Asger

    2014-01-01

    We present a quantum mechanical approach to calculate broadening of plasmonic resonances in metallic nanostructures due to collisions of electrons with the surface of the structure. The approach is applicable if the characteristic size of the structure is much larger than the de Broglie electron ...

  11. Experimental characterization of dielectric-loaded plasmonic waveguide-racetrack resonators at near-infrared wavelengths

    DEFF Research Database (Denmark)

    Garcia, Cesar; Coello, Victor; Han, Zhanghua

    2012-01-01

    Dielectric-loaded plasmonic waveguide-racetrack resonators (WRTRs) were designed and fabricated for operating at near-infrared wavelengths (750–850 nm) and characterized using leakage-radiation microscopy. The transmission spectra of the WRTRs are found experimentally and compared to the calculat...

  12. Enhanced Electron Photoemission by Collective Lattice Resonances in Plasmonic Nanoparticle-Array Photodetectors and Solar Cells

    DEFF Research Database (Denmark)

    Zhukovsky, Sergei; Babicheva, Viktoriia; Uskov, Alexander

    2014-01-01

    -particle excitations (localized surface plasmon resonances) leads to stronger local field enhancement. In turn, this causes a significant increase of the photocurrent compared to the case when only individual-particle excitations are present. The results can be used to design new photodetectors with highly selective...

  13. Design of plasmonic photonic crystal resonant cavities for polarization sensitive infrared photodetectors

    Science.gov (United States)

    Rosenberg, Jessie; Shenoi, Rajeev V.; Krishna, Sanjay; Painter, Oskar

    2010-02-01

    We design a polarization-sensitive resonator for use in midinfrared photodetectors, utilizing a photonic crystal cavity and a single or double-metal plasmonic waveguide to achieve enhanced detector efficiency due to superior optical confinement within the active region. As the cavity is highly frequency and polarization-sensitive, this resonator structure could be used in chip-based infrared spectrometers and cameras that can distinguish among different materials and temperatures to a high degree of precision.

  14. Polymer films with size-selected silver nanoparticles as plasmon resonance-based transducers for protein sensing

    DEFF Research Database (Denmark)

    Muhammad, Hanif; Juluri, Raghavendra Rao; Fojan, Peter

    2016-01-01

    Transducers based on the phenomenon of localised surface plasmon resonance (LSPR) are fabricated using silver nanoparticles (NPs) imbedded into thin poly (methyl methacrylate) films. The particles are produced by magnetron sputtering, size selected with a precision ≤ 10% of the diameter...... and deposited on the films in vacuum. Immersion of NPs is controlled by post-deposition thermal annealing providing very good adhesion, in particular, resistance against following wet chemical procedures. LSPR properties of silver NPs are exploited for protein detection using a classical antibody-antigen scheme...

  15. Angle-tunable enhanced infrared reflection absorption spectroscopy via grating-coupled surface plasmon resonance.

    Science.gov (United States)

    Petefish, Joseph W; Hillier, Andrew C

    2014-03-04

    Surface enhanced infrared absorption (SEIRA) spectroscopy is an attractive method for increasing the prominence of vibrational modes in infrared spectroscopy. To date, the majority of reports associated with SEIRA utilize localized surface plasmon resonance from metal nanoparticles to enhance electromagnetic fields in the region of analytes. Limited work has been performed using propagating surface plasmons as a method for SEIRA excitation. In this report, we demonstrate angle-tunable enhancement of vibrational stretching modes associated with a thin poly(methyl methacrylate) (PMMA) film that is coupled to a silver-coated diffraction grating. Gratings are fabricated using laser interference lithography to achieve precise surface periodicities, which can be used to generate surface plasmons that overlap with specific vibrational modes in the polymer film. Infrared reflection absorption spectra are presented for both bare silver and PMMA-coated silver gratings at a range of angles and polarization states. In addition, spectra were obtained with the grating direction oriented perpendicular and parallel to the infrared source in order to isolate plasmon enhancement effects. Optical simulations using the rigorous coupled-wave analysis method were used to identify the origin of the plasmon-induced enhancement. Angle-dependent absorption measurements achieved signal enhancements of more than 10-times the signal in the absence of the plasmon.

  16. Standing-wave resonances in plasmonic nanoumbrella cavities for color generation and colorimetric refractive index sensor

    Science.gov (United States)

    Fan, Jiaorong; Li, Zhongyuan; Chen, Zhuojie; Wu, Wengang

    2016-10-01

    We theoretically investigate the hybridization of the elemental surface plasmons in umbrella-shape plasmonic nanostructures and experimentally demonstrate the implementation of plasmonic multicolor metasurfaces as well as their application in colorimetric sensing. The three-dimension metallic umbrella arrays consist of a periodic canopy-capped-nanopillars with metal-coated sidewall and a backplane metal-film to form vertical nanocavity of canopy and film. Plasmonic coupling and energy confinement in nanocavity induce a noticeably resonance narrowing of multispectral reflection. The metasurfaced nanostructures appeared in vibrant and tunable colors with broad gamut derived from color blending mechanism due to multiple, narrow-band resonances. Vivid colors varied from red, yellow, green, blue to violet are easily achieved. It is also shown that such plasmonic metasurfaces can work as the feasible and real-time colorimetric refractive index sensor by measuring the distinct color variation to glucose concentration changes. Our sensor scheme shows its spectral sensitivity in the periodic umbrella array with respect to the refractive index change to be 242.5 nm/RIU with a figure of merit of 7.3. Furthermore, a refractive index resolution of colorimetric sensing up to 0.025 RIU has been accomplished.

  17. 椭圆截面金纳米管的局域表面等离激元共振特性研究%Localized surface plasmon resonance properties of elliptical gold nanotubes

    Institute of Scientific and Technical Information of China (English)

    丛超; 吴大建; 刘晓峻

    2011-01-01

    The effects of ellipse shape, polarization direction of incident light, shell thickness, and dielectric constants of core and embedding medium on the localized surface plasmon resonance ( LSPR ) of elliptical gold nanotube have been investigated by the Finite Difference Time Domain (FDTD) method.When the semimajor axis is fixed, it is found that with the increase of the semiminor axis of the ellipse the extinction peak of the gold nanotube has a red-shift.With the increase of the angle between the incident polarization and the semimajor axis, the extinction peak has a red-shift.With the shell thickness decreasing, the extinction peak of gold nanotube also has a red-shift.Furthermore, we also find that the increase of the dielectric constant for core or embedding medium will induce a red-shift of LSPR in gold nanotube.The change of the extinction peak is ascribed to the plasmon hybridization and the competition between the variations of conduction and oscillation electrons.%基于时域有限差分方法研究了几何形状、入射电场偏振方向、管壁厚度及内核和包埋介质的变化对椭圆截面金纳米管局域表面等离激元共振特性的影响.研究发现,当长轴固定时,短轴的减小将导致纳米管消光峰红移;入射电场偏振方向与椭圆长轴夹角的增大将导致消光峰红移;当颗粒整体尺寸不变时,管壁厚度减小同样会使得消光峰红移.此外,内核及包埋介质介电常数的增大均导致消光峰红移.利用等离激元杂化理论及自由电子和振荡电子竞争机理对上述现象进行了理论分析.

  18. Spatiotemporal properties of nanoshell plasmonic response for strong-field experiments

    Science.gov (United States)

    Weber, S. J.; Colas des Francs, G.; Girard, C.

    2015-05-01

    Field enhancement behavior of a SiO2/Au nanoshell is studied in the framework of strong-field physics. Localized plasmonic fields induce local electric field enhancement with the potential to lead to the strong-field regime without the use of costly amplified lasers. In this framework, electrons are tunnel ionized from the nanoshell and accelerated by the local field being spatially inhomogeneous in terms of spectral and polarization properties. These processes are happening within a single laser shot, and thermal effects are therefore neglected. We show that the localized response to ultrashort femtosecond pulses can be investigated by extending Mie theory to multilayer spherical particles. Nanoshell plasmonic resonances can be easily tuned depending on the volume ratio between core and whole particle. Optimum geometric parameters of the nanoshell are selected for use with ultrashort pulses centered at 800 nm where most femtosecond oscillators operate. It is shown that phase and amplitude reshaping of the incident pulse by the plasmonic resonance can be partially corrected using active shaping leading to ultrashort response of the medium. Finally, free electron classical trajectories are calculated to highlight the inhomogeneous nature of the local enhancement in a strong-field picture.

  19. Optical properties of plasmonic nanoantenna arrays based on H-shaped nanoparticles with extended arms

    Science.gov (United States)

    Turkmen, Mustafa; Aslan, Erdem

    2014-03-01

    In this study, we present the optical properties of a plasmonic nanoantenna array based on H-shaped gold nanoparticles with extended arms, which can be used for infrared detection applications. Plasmonic nanoantennas operating at the infrared and visible region provide a unique way to capture, control and manipulate light at the nanoscale through the excitation of collective electron oscillations known as surface plasmons. The unit cell of proposed antenna consists of one H-shaped nanostructure and two extended arms located on the lateral sides of this nanostructure. We will demonstrate the proposed antenna has a dual band spectral response and the locations of the resonance frequencies can be adjusted by changing the geometrical dimensions of both the H-shaped nanoparticles and the extended arms. Theoretical calculations of the reflectance spectra of the nanoantenna array are performed by using simulation software, which utilizes Finite Difference Time Domain (FDTD) method. In order to show the sensing capacity of the structure, the effect of the dielectric medium on the resonance frequency is also determined. The results show that the proposed antenna can be utilized for infrared sensing applications.

  20. Improved Coupling to Plasmonic Slot Waveguide via a Resonant Nanoantenna

    DEFF Research Database (Denmark)

    Andryieuski, Andrei; Zenin, Vladimir A.; Malureanu, Radu;

    -limited optical waves into deep-subwavelength plasmonic waveguides. In this contribution we provide a systematic approach to design, fabricate and characterize an efficient, broadband, and compact dipole antenna nanocoupler for the telecom wavelength range around 1.55 µm. We consider the vertical coupling...... configuration with a realistic excitation directly from an optical fiber. The scattering-type scanning near-field optical microscope (s-SNOM) characterization allows us not only to make relative comparison of the efficiencies (in terms of the effective area) of different couplers, but also to measure......Plasmonic waveguides are considered as a future generation of optical interconnects in integrated circuits for datacom technologies due to their extreme field confinement performance. Inevitably, when using nanoscale waveguides, a new challenge emerges: how to effectively couple the diffraction...

  1. Resonance Coupling in Plasmonic Nanomatryoshka Homo- and Heterodimers

    Science.gov (United States)

    2016-08-16

    breaking and conductive contact on the plasmon coupling in gold nanorod dimers,” ACS Nano 4, 4657-4666 (2010). 19 B. Luk’yanchuk, N. I. Zheludev, S. A...gold nanorods,” ACS Nano 5, 5976-5986 (2011). 21 Y, -I. Xu, “Electromagnetic scattering by an aggregate of spheres,” Appl. Opt. 34, 4573-4588 (1995). 22

  2. Plasmonic resonators for enhanced diamond NV- center single photon sources

    OpenAIRE

    Bulu, Irfan; Babinec, Thomas; Hausmann, Birgit; Choy, Jennifer T.; Loncar, Marko

    2011-01-01

    We propose a novel source of non-classical light consisting of plasmonic aperture with single-crystal diamond containing a single Nitrogen-Vacancy (NV) color center. Theoretical calculations of optimal structures show that these devices can simultaneously enhance optical pumping by a factor of 7, spontaneous emission rates by Fp ~ 50 (Purcell factor), and offer collection efficiencies up to 40%. These excitation and collection enhancements occur over a broad range of wavelengths (~30nm), and ...

  3. Analysis of plasmon resonances in metallic nanostructures in proximity to dielectric objects with application to heat-assisted magnetic recording

    Science.gov (United States)

    Hung, L.; McAvoy, P.; Bowen, D.; Krafft, C.; Mayergoyz, I.

    2014-05-01

    A novel approach to the calculation of plasmon resonance in metallic nanoparticle located nearby a dielectric object is presented. The plasmon resonance problem for such structure is formulated as a constrained eigenvalue problem for specific coupled boundary integral equations. By solving this eigenvalue problem, the resonance frequencies (wavelengths) of the metallic nanoparticle as well as the corresponding plasmon modes are computed. In this paper, two examples of application are considered and a good agreement between the computational results and analytical solution as well as with available experimental and numerical data is demonstrated.

  4. Interplay between out-of-plane magnetic plasmon and lattice resonance for modified resonance lineshape and near-field enhancement in double nanoparticles array

    CERN Document Server

    Ding, Pei; He, Jinna; Fan, Chunzhen; Cai, Genwang; Liang, Erjun

    2013-01-01

    Two-dimensional double nanoparticles (DNPs) arrays are demonstrated theoretically supporting the interaction of out-of-plane magnetic plasmons and in-plane lattice resonances, which can be achieved by tuning the nanoparticle height or the array period due to the height-dependent magnetic resonance and the periodicity-dependent lattice resonance. The interplay of the two plasmon modes can lead to a remarkable change in resonance lineshape and an improvement of magnetic field enhancement. Simultaneous electric field and magnetic field enhancements can be obtained in the gap regions between neighboring particles at two resonance frequencies as the interplay occurs, which present open cavities as electromagnetic field hot spots for potential applications on detection and sensing. The results not only offer an attractive way to tune the optical responses of plasmonic nanostructure, but also provide further insight into the plasmons interactions in periodic nanostructure or metamaterials comprising multiple element...

  5. Surface plasmon resonance optical sensor and antibacterial activities of biosynthesized silver nanoparticles

    Science.gov (United States)

    Bindhu, M. R.; Umadevi, M.

    2014-03-01

    Silver nanoparticles were prepared using aqueous fruit extract of Ananas comosus as reducing agent. These silver nanoparticles showed surface plasmon peak at 439 nm. They were monodispersed and spherical in shape with an average particle size of 10 nm. The crystallinity of these nanoparticles was evident from clear lattice fringes in the HRTEM images and bright circular spots in the SAED pattern. The antibacterial activities of prepared nanoparticles were found to be size-dependent, the smaller nanoparticles showing more bactericidal effect. Aqueous Zn2+ and Cu4+ selectivity and sensitivity study of this green synthesized nanoparticle was performed by optical sensor based surface plasmon resonance (SPR) at room temperature.

  6. Novel piezoelectric effect and surface plasmon resonance-based elements for MEMS applications.

    Science.gov (United States)

    Ponelyte, Sigita; Palevicius, Arvydas

    2014-04-17

    This paper covers research on novel thin films with periodical microstructure--optical elements, exhibiting a combination of piezoelectric and surface plasmon resonance effects. The research results showed that incorporation of Ag nanoparticles in novel piezoelectric--plasmonic elements shift a dominating peak in the visible light spectrum. This optical window is essential in the design of optical elements for sensing systems. Novel optical elements can be tunable under defined bias and change its main grating parameters (depth and width) influencing the response of diffraction efficiencies. These elements allow opening new avenues in the design of more sensitive and multifunctional microdevices.

  7. Fiber Optic Surface Plasmon Resonance-Based Biosensor Technique: Fabrication, Advancement, and Application.

    Science.gov (United States)

    Liang, Gaoling; Luo, Zewei; Liu, Kunping; Wang, Yimin; Dai, Jianxiong; Duan, Yixiang

    2016-05-03

    Fiber optic-based biosensors with surface plasmon resonance (SPR) technology are advanced label-free optical biosensing methods. They have brought tremendous progress in the sensing of various chemical and biological species. This review summarizes four sensing configurations (prism, grating, waveguide, and fiber optic) with two ways, attenuated total reflection (ATR) and diffraction, to excite the surface plasmons. Meanwhile, the designs of different probes (U-bent, tapered, and other probes) are also described. Finally, four major types of biosensors, immunosensor, DNA biosensor, enzyme biosensor, and living cell biosensor, are discussed in detail for their sensing principles and applications. Future prospects of fiber optic-based SPR sensor technology are discussed.

  8. A saccharides sensor developed by symmetrical optical waveguide-based surface plasmon resonance

    OpenAIRE

    Ang Li; Zhouyi Guo; Qing Peng; Chan Du; Xida Han; Le Liu; Jun Guo; Yonghong He; Yanhong Ji

    2015-01-01

    We proposed a new saccharides sensor developed by symmetrical optical waveguide (SOW)-based surface plasmon resonance (SPR). This unique MgF2/Au/MgF2/Analyte film structure results in longer surface plasmon wave (SPW) propagation lengths and depths, leading to an increment of resolution. In this paper, we managed to decorate the dielectric interface (MgF2 layer) by depositing a thin polydopamine film as surface-adherent that provides a platform for secondary reactions with the probe molecule....

  9. Tunable surface plasmon resonance of silver nanoclusters in ion exchanged soda lime glass

    Energy Technology Data Exchange (ETDEWEB)

    Mohapatra, Satyabrata, E-mail: smiuac@gmail.com

    2014-06-15

    Highlights: • Ag-glass nanocomposites were synthesized by silver ion exchange and annealing. • SPR of Ag-glass nanocomposites was tuned from 420 to 596 nm by annealing in air. • Subsequent annealing of nanocomposites in Ar + H{sub 2} reversed back SPR to 398 nm. • Formation/dissolution of Ag{sub 2}O nanoshells around Ag nanoclusters lead to tunable SPR. - Abstract: Silver (Ag) nanoclusters embedded in soda lime glass were synthesized by Ag ion exchange followed by thermal annealing. The effects of annealing temperature, time and atmosphere on the plasmonic response, structural and optical properties of silver-glass nanocomposites have been investigated using UV–visible absorption spectroscopy and X-ray photoelectron spectroscopy (XPS). As exchanged sample exhibits surface plasmon resonance (SPR) band around 420 nm which showed regular red shift with increase in annealing temperature. A significant red shift of 176 nm (from 420 to 596 nm) and broadening of the SPR peak was observed for annealing in air at 450 °C. XPS studies on air annealed samples confirmed the presence of Ag{sub 2}O in addition to Ag. Subsequent annealing at 250 °C in reducing atmosphere resulted in increase in intensity, narrowing and blue shift of the SPR peak to 398 nm. Our observations suggest that SPR tunability is mainly due to the formation and dissolution of Ag{sub 2}O nanoshells around Ag nanoclusters in the near-surface region of glass during annealing in oxidizing and reducing atmosphere, respectively.

  10. Study of plasmon resonance in a gold nanorod with an LC circuit model

    CERN Document Server

    Huang, Cheng-ping; Huang, Huang; Zhu, Yong-yuan

    2009-01-01

    Gold nanorod has generated great research interest due to its tunable longitudinal plasmon resonance. However, little progress has been made in the understanding of the effect. A major reason is that, except for metallic spheres and ellipsoids, the interaction between light and nanoparticles is generally insoluble. In this paper, a new scheme has been proposed to study the plasmon resonance of gold nanorod, in which the nanorod is modeled as an LC circuit with an inductance and a capacitance. The obtained resonance wavelength is dependent on not only aspect ratio but also rod radius, suggesting the importance of self-inductance and the breakdown of linear scaling. Moreover, the cross sections for light scattering and absorption have been deduced analytically, giving rise to a Lorentzian line-shape for the extinction spectrum. The result provides us with new insight into the phenomenon.

  11. Analogy of electromagnetically induced transparency in plasmonic nanodisk with a square ring resonator

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xianping; Wei, Zhongchao, E-mail: wzc@scnu.edu.cn; Liu, Yuebo; Zhong, Nianfa; Tan, Xiaopei; Shi, Songsong; Liu, Hongzhan; Liang, Ruisheng

    2016-01-08

    We have demonstrated the analogy of electromagnetically induced transparency in plasmonic nanodisk with a square ring resonator. A reasonable analysis of the transmission feature based on the temporal coupled-mode theory is given and shows good agreement with the Finit-Difference Time-Domain simulation. The transparency window can be easily tuned by changing the geometrical parameters and the insulator filled in the resonator. The transmission of the resonator system is close to 80% and the full width at half maximum is less than 46 nm. The sensitivity of the structure is about 812 nm/RIU. These characteristics make the new system with potential to apply for optical storage, ultrafast plasmonic switch and slow-light devices.

  12. Detection of biomolecules and bioconjugates by monitoring rotated grating-coupled surface plasmon resonance

    CERN Document Server

    Szalai, Aniko; Somogyi, Aniko; Szenes, Andras; Banhelyi, Balazs; Csapo, Edit; Dekany, Imre; Csendes, Tibor; Csete, Maria

    2016-01-01

    Plasmonic biosensing chips were prepared by fabricating wavelength-scaled dielectric-metal interfacial gratings on thin polycarbonate films covered bimetal layers via two-beam interference laser lithography. Lysozyme (LYZ) biomolecules and gold nanoparticle (AuNP-LYZ) bioconjugates with 1:5 mass ratio were seeded onto the biochip surfaces. Surface plasmon resonance spectroscopy was performed before and after biomolecule seeding in a modified Kretschmann-arrangement by varying the azimuthal and polar angles to optimize the conditions for rotated grating-coupling. The shift of secondary and primary resonance peaks originating from rotated grating-coupling phenomenon was monitored to detect the biomolecule and bioconjugate adherence. Numerical calculations were performed to reproduce the measured reflectance spectra and the resonance peak shifts caused by different biocoverings. Comparison of measurements and calculations proved that monitoring the narrower secondary peaks under optimal rotated-grating coupling ...

  13. Antimicrobial dependence of silver nanoparticles on surface plasmon resonance bands against Escherichia coli

    Directory of Open Access Journals (Sweden)

    Mlalila NG

    2016-12-01

    Full Text Available Nichrous G Mlalila,1,2 Hulda Shaidi Swai,1 Askwar Hilonga,3 Dattatreya M Kadam2 1School of Life Sciences and Bioengineering, Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania; 2ICAR-Central Institute of Post-Harvest Engineering and Technology (ICAR-CIPHET, Ludhiana, Punjab, India; 3Department of Materials Science and Engineering, Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania Abstract: This study presents a simple and trouble-free method for determining the antimicrobial properties of silver nanoparticles (AgNPs based on the surface plasmon resonance (SPR bands. AgNPs were prepared by chemical reduction method using silver nitrates as a metallic precursor and formaldehyde (HCHO as a reducing agent and capped by polyethylene glycol. Effects of several processing variables on the size and shape of AgNPs were monitored using an ultraviolet–visible spectrophotometer based on their SPR bands. The formed particles showing various particle shapes and full width at half maximum (FWHM were tested against Escherichia coli by surface spreading using agar plates containing equal amounts of selected AgNPs samples. The NPs exhibited higher antimicrobial properties; however, monodispersed spherical NPs with narrow FWHM were more effective against E. coli growth. The NPs prepared are promising candidates in diverse applications such as antimicrobial agents in the food and biomedical industries. Keywords: antimicrobial agent, bandwidth, full width at half maximum, nanoparticles, particle size

  14. Topological Nanocolloids with Facile Electric Switching of Plasmonic Properties

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Ye; Smalyukh, Ivan I.

    2015-12-01

    Combining topology and plasmonics paradigms in nanocolloidal systems may enable new means of pre-engineering desired composite material properties. Here we design and realize orientationally ordered assemblies of noble metal nanoparticles with genus-one topology and unusual long-range ordering mediated by their interactions with the surrounding nematic fluid host. Facile electric switching of these composites is reminiscent of that of pristine liquid crystals (LCs), but provides a means of reconfiguring the nanoparticle assembly and thus also the ensuing composite medium's optical properties. Our findings may lead to formation of new molecular-colloidal soft matter phases with unusual optical properties, as well as optical metamaterials.

  15. Plasmon coupling of magnetic resonances in an asymmetric gold semishell

    Science.gov (United States)

    Ye, Jian; Kong, Yan; Liu, Cheng

    2016-05-01

    The generation of magnetic dipole resonances in metallic nanostructures is of great importance for constructing near-zero or even negative refractive index metamaterials. Commonly, planar two-dimensional (2D) split-ring resonators or relevant structures are basic elements of metamaterials. In this work, we introduce a three-dimensional (3D) asymmetric Au semishell composed of two nanocups with a face-to-face geometry and demonstrate two distinct magnetic resonances spontaneously in the visible-near infrared optical wavelength regime. These two magnetic resonances are from constructive and destructive hybridization of magnetic dipoles of individual nanocups in the asymmetric semishell. In contrast, complete cancellation of magnetic dipoles in the symmetric semishell leads to only a pronounced electric mode with near-zero magnetic dipole moment. These 3D asymmetric resonators provide new ways for engineering hybrid resonant modes and ultra-high near-field enhancement for the design of 3D metamaterials.

  16. Localized surface plasmon polariton resonance in holographically structured Al-doped ZnO

    Science.gov (United States)

    George, David; Li, Li; Jiang, Yan; Lowell, David; Mao, Michelle; Hassan, Safaa; Ding, Jun; Cui, Jingbiao; Zhang, Hualiang; Philipose, Usha; Lin, Yuankun

    2016-07-01

    In this paper, we studied the localized surface plasmon polariton (SPP) resonance in hole arrays in transparent conducting aluminum-doped zinc oxide (AZO). CMOS-compatible fabrication process was demonstrated for the AZO devices. The localized SPP resonance was observed and confirmed by electromagnetic simulations. Using a standing wave model, the observed SPP was dominated by the standing-wave resonance along (1,1) direction in square lattices. This research lays the groundwork for a fabrication technique that can contribute to the core technology of future integrated photonics through its extension into tunable conductive materials.

  17. A novel optical pressure sensor based on surface plasmon polariton resonator

    Science.gov (United States)

    Wu, Jing; Lang, Peilin; Chen, Xi; Zhang, Ru

    2016-02-01

    We propose a Metal-Insulator-Metal structure consists of two surface plasmon polaritons (SPPs) and an H-shaped resonator. The reflectance spectrum is numerically simulated by the two-dimensional finite-difference time-domain method. The results show that this structure can act as a pressure sensor. To our knowledge, this is the first proposal to utilize the SPP resonator to form a pressure sensor. The size of the SPP resonator can be as small as a few hundred nanometers. The nano-scale pressure sensor opens a wide field for potential applications in biological and biomedical engineering.

  18. Localized surface plasmon polariton resonance in holographically structured Al-doped ZnO

    Energy Technology Data Exchange (ETDEWEB)

    George, David; Lowell, David; Mao, Michelle; Hassan, Safaa; Philipose, Usha [Department of Physics and Center for Advanced Research and Technology, University of North Texas, Denton, Texas 76203 (United States); Li, Li; Jiang, Yan; Cui, Jingbiao [Department of Physics and Materials Science, University of Memphis, Memphis, Tennessee 38152 (United States); Ding, Jun; Zhang, Hualiang [Department of Electrical and Computer Engineering, University of Massachusetts Lowell, Lowell, Massachusetts 01854 (United States); Lin, Yuankun [Department of Physics and Center for Advanced Research and Technology, University of North Texas, Denton, Texas 76203 (United States); Department of Electrical Engineering, University of North Texas, Denton, Texas 76203 (United States)

    2016-07-28

    In this paper, we studied the localized surface plasmon polariton (SPP) resonance in hole arrays in transparent conducting aluminum-doped zinc oxide (AZO). CMOS-compatible fabrication process was demonstrated for the AZO devices. The localized SPP resonance was observed and confirmed by electromagnetic simulations. Using a standing wave model, the observed SPP was dominated by the standing-wave resonance along (1,1) direction in square lattices. This research lays the groundwork for a fabrication technique that can contribute to the core technology of future integrated photonics through its extension into tunable conductive materials.

  19. Bimetallic structure fabricated by laser interference lithography for tuning surface plasmon resonance.

    Science.gov (United States)

    Liu, C H; Hong, M H; Cheung, H W; Zhang, F; Huang, Z Q; Tan, L S; Hor, T S A

    2008-07-07

    Tuning of surface plasmon resonance by gold and silver bimetallic thin film and bimetallic dot array is investigated. Laser interference lithography is applied to fabricate the nanostructures. A bimetallic dot structure is obtained by a lift-off procedure after gold and silver thin film deposition by an electron beam evaporator. Surface plasmon behaviors of these films and nanostructures are studied using UV-Vis spectroscopy. It is observed that for gold thin film on quartz substrate, the optical spectral peak is blue shifted when a silver thin film is coated over it. Compared to the plasmon band in single metal gold dot array, the bimetallic nanodot array shows a similar blue shift in its spectral peak. These shifts are both attributed to the interaction between gold and silver atoms. Electromagnetic interaction between gold and silver nanostructures is discussed using a simplified spring model.

  20. Surface-Plasmon-Polariton Laser based on an Open-Cavity Fabry-Perot Resonator

    CERN Document Server

    Zhu, Wenqi; Agrawal, Amit; Lezec, Henri J

    2016-01-01

    Recent years have witnessed growing interest in the development of small-footprint lasers for potential applications in small-volume sensing and on-chip optical communications. Surface-plasmons, electromagnetic modes evanescently confined to metal-dielectric interfaces, offer an effective route to achieving lasing at nanometer-scale dimensions when resonantly amplified in contact with a gain-medium. Here, we achieve visible frequency ultra-narrow linewidth lasing at room-temperature by leveraging surface plasmons propagating in an open Fabry-Perot cavity formed by a flat metal surface coated with a subwavelength-thick layer of optically-pumped gain medium and orthogonally bound by a pair of flat metal sidewalls. Low perturbation transmission-configuration sampling of the lasing plasmon mode is achieved via an evanescently coupled recessed nanoslit, opening the way to high-figure-of-merit refractive-index sensing of analytes interacting with the open cavity.

  1. Recent Development of Plasmonic Resonance-Based Photocatalysis and Photovoltaics for Solar Utilization

    Directory of Open Access Journals (Sweden)

    Wenguang Fan

    2016-02-01

    Full Text Available Increasing utilization of solar energy is an effective strategy to tackle our energy and energy-related environmental issues. Both solar photocatalysis (PC and solar photovoltaics (PV have high potential to develop technologies of many practical applications. Substantial research efforts are devoted to enhancing visible light activation of the photoelectrocatalytic reactions by various modifications of nanostructured semiconductors. This review paper emphasizes the recent advancement in material modifications by means of the promising localized surface plasmonic resonance (LSPR mechanisms. The principles of LSPR and its effects on the photonic efficiency of PV and PC are discussed here. Many research findings reveal the promise of Au and Ag plasmonic nanoparticles (NPs. Continual investigation for increasing the stability of the plasmonic NPs will be fruitful.

  2. Recent Development of Plasmonic Resonance-Based Photocatalysis and Photovoltaics for Solar Utilization.

    Science.gov (United States)

    Fan, Wenguang; Leung, Michael K H

    2016-02-02

    Increasing utilization of solar energy is an effective strategy to tackle our energy and energy-related environmental issues. Both solar photocatalysis (PC) and solar photovoltaics (PV) have high potential to develop technologies of many practical applications. Substantial research efforts are devoted to enhancing visible light activation of the photoelectrocatalytic reactions by various modifications of nanostructured semiconductors. This review paper emphasizes the recent advancement in material modifications by means of the promising localized surface plasmonic resonance (LSPR) mechanisms. The principles of LSPR and its effects on the photonic efficiency of PV and PC are discussed here. Many research findings reveal the promise of Au and Ag plasmonic nanoparticles (NPs). Continual investigation for increasing the stability of the plasmonic NPs will be fruitful.

  3. Surface-enhanced Raman spectroscopy on a surface plasmon resonance biosensor platform for gene diagnostics

    Science.gov (United States)

    Yuan, W.; Ho, H. P.; Suen, Y. K.; Kong, S. K.; Lin, Chinlon; Prasad, Paras N.; Li, J.; Ong, Daniel H. C.

    2008-02-01

    We propose to integrate the surface-enhanced Raman spectroscopy (SERS) detection capability with a surface plasmon resonance (SPR) biosensor platform. As a demonstration setup, the experimental scheme is built from a Total Internal Reflection Fluorescence (TIRF) microscope. The sample surface is a gold-coated plasmonic crystal substrate. Two oligonucleotide (ODN) probes that have been labeled with two different Raman active dyes are used to achieve a sandwich assay of target ODNs or polynucleotide. Upon complementary hybridizations between the target and probe ODNs, the target can be identified by detecting the narrow-band spectroscopic fingerprints of the Raman tags. This concept has high potential for achieving multiplexed detection of ODN targets because a very large number of probes can be incorporated to the plasmonic crystal substrate, which may find applications in gene based diseases diagnostics. We also explored the detection of single molecules and achieved some preliminary results.

  4. Surface plasmon resonance in nanocrystalline gold-copper alloy films.

    Science.gov (United States)

    Hussain, S; Datta, Subhadeep; Roy, R K; Pal, A K

    2007-12-01

    Nanocrystalline Au(x)Cu(1-x) films were synthesized by depositing Cu/Au/Cu multilayer in nanocrystalline thin film form with requisite thickness of individual layers onto fused silica substrates by high pressure sputtering technique. The absorbance spectra showed only one surface plasmon peak for all the compositions with the exception that the peak position did not indicate gradual shift as gold concentration was increased. Peak position for the two compositions corresponding to the two superlattice structures, AuCu3 and AuCu, deviated significantly from linear variation. The experimental results have been discussed in light of the existing Mie theory and the Core-shell model.

  5. Plasmonic photocatalysis.

    Science.gov (United States)

    Zhang, Xuming; Chen, Yu Lim; Liu, Ru-Shi; Tsai, Din Ping

    2013-04-01

    Plasmonic photocatalysis has recently facilitated the rapid progress in enhancing photocatalytic efficiency under visible light irradiation, increasing the prospect of using sunlight for environmental and energy applications such as wastewater treatment, water splitting and carbon dioxide reduction. Plasmonic photocatalysis makes use of noble metal nanoparticles dispersed into semiconductor photocatalysts and possesses two prominent features-a Schottky junction and localized surface plasmonic resonance (LSPR). The former is of benefit to charge separation and transfer whereas the latter contributes to the strong absorption of visible light and the excitation of active charge carriers. This article aims to provide a systematic study of the fundamental physical mechanisms of plasmonic photocatalysis and to rationalize many experimental observations. In particular, we show that LSPR could boost the generation of electrons and holes in semiconductor photocatalysts through two different effects-the LSPR sensitization effect and the LSPR-powered bandgap breaking effect. By classifying the plasmonic photocatalytic systems in terms of their contact form and irradiation state, we show that the enhancement effects on different properties of photocatalysis can be well-explained and systematized. Moreover, we identify popular material systems of plasmonic photocatalysis that have shown excellent performance and elucidate their key features in the context of our proposed mechanisms and classifications.

  6. Underpotential deposition of a copper monolayer on a gold film sensed by integrated optical surface plasmon resonance

    OpenAIRE

    Abanulo, J.C.; Harris, R.D.; Bartlett, P.N.; Wilkinson, J.S.

    2000-01-01

    An integrated optical surface plasmon resonance sensor combined with electrochemical control is used to monitor the underpotential deposition of a copper monolayer onto a gold film from 1 mM Cu2+ in 0.1 M perchloric acid.

  7. A subwavelength plasmonic metamolecule exhibiting magnetic-based optical Fano resonance

    Science.gov (United States)

    Shafiei, Farbod; Monticone, Francesco; Le, Khai Q.; Liu, Xing-Xiang; Hartsfield, Thomas; Alù, Andrea; Li, Xiaoqin

    2013-02-01

    The lack of symmetry between electric and magnetic charges, a fundamental consequence of the small value of the fine-structure constant, is directly related to the weakness of magnetic effects in optical materials. Properly tailored plasmonic nanoclusters have been proposed recently to induce artificial optical magnetism based on the principle that magnetic effects are indistinguishable from specific forms of spatial dispersion of permittivity at optical frequencies. In a different context, plasmonic Fano resonances have generated a great deal of interest, particularly for use in sensing applications that benefit from sharp spectral features and extreme field localization. In the absence of natural magnetism, optical Fano resonances have so far been based on purely electric effects. In this Letter, we demonstrate that a subwavelength plasmonic metamolecule consisting of four closely spaced gold nanoparticles supports a strong magnetic response coupled to a broad electric resonance. Small structural asymmetries in the assembled nanoring enable the interaction between electric and magnetic modes, leading to the first observation of a magnetic-based Fano scattering resonance at optical frequencies. Our findings are supported by excellent agreement with simulations and analytical calculations, and represent an important step towards the quest for artificial magnetism and negative refractive index metamaterials at optical frequencies.

  8. Competition Between Resonant Plasmonic Coupling and Electrostatic Interaction in Reduced Graphene Oxide Quantum Dots

    Science.gov (United States)

    Karna, Sanjay; Mahat, Meg; Choi, Tae-Youl; Shimada, Ryoko; Wang, Zhiming; Neogi, Arup

    2016-11-01

    The light emission from reduced graphene oxide quantum dots (rGO-QDs) exhibit a significant enhancement in photoluminescence (PL) due to localized surface plasmon (LSP) interactions. Silver and gold nanoparticles (NPs) coupled to rGO nanoparticles exhibit the effect of resonant LSP coupling on the emission processes. Enhancement of the radiative recombination rate in the presence of Ag-NPs induced LSP tuned to the emission energy results in a four-fold increase in PL intensity. The localized field due to the resonantly coupled LSP modes induces n-π* transitions that are not observed in the absence of the resonant interaction of the plasmons with the excitons. An increase in the density of the Ag-NPs result in a detuning of the LSP energy from the emission energy of the nanoparticles. The detuning is due to the cumulative effect of the red-shift in the LSP energy and the electrostatic field induced blue shift in the PL energy of the rGO-QDs. The detuning quenches the PL emission from rGO-QDs at higher concentration of Ag NPs due to non-dissipative effects unlike plasmon induced Joule heating that occurs under resonance conditions. An increase in Au nanoparticles concentration results in an enhancement of PL emission due to electrostatic image charge effect.

  9. Competition Between Resonant Plasmonic Coupling and Electrostatic Interaction in Reduced Graphene Oxide Quantum Dots.

    Science.gov (United States)

    Karna, Sanjay; Mahat, Meg; Choi, Tae-Youl; Shimada, Ryoko; Wang, Zhiming; Neogi, Arup

    2016-11-22

    The light emission from reduced graphene oxide quantum dots (rGO-QDs) exhibit a significant enhancement in photoluminescence (PL) due to localized surface plasmon (LSP) interactions. Silver and gold nanoparticles (NPs) coupled to rGO nanoparticles exhibit the effect of resonant LSP coupling on the emission processes. Enhancement of the radiative recombination rate in the presence of Ag-NPs induced LSP tuned to the emission energy results in a four-fold increase in PL intensity. The localized field due to the resonantly coupled LSP modes induces n-π* transitions that are not observed in the absence of the resonant interaction of the plasmons with the excitons. An increase in the density of the Ag-NPs result in a detuning of the LSP energy from the emission energy of the nanoparticles. The detuning is due to the cumulative effect of the red-shift in the LSP energy and the electrostatic field induced blue shift in the PL energy of the rGO-QDs. The detuning quenches the PL emission from rGO-QDs at higher concentration of Ag NPs due to non-dissipative effects unlike plasmon induced Joule heating that occurs under resonance conditions. An increase in Au nanoparticles concentration results in an enhancement of PL emission due to electrostatic image charge effect.

  10. Giant second harmonic generation by engineering of double plasmonic resonances at nanoscale

    CERN Document Server

    Ren, Ming-Liang; Wang, Ben-Li; Chen, Bao-Qin; Li, Jiafang; Li, Zhi-Yuan

    2014-01-01

    We have investigated second harmonic generation (SHG) from Ag-coated LiNbO3 (LN) core-shell nanocuboids and found that giant SHG can occur via deliberately designed double plasmonic resonances. By controlling the aspect ratio, we can tune fundamental wave (FW) and SHG signal to match the longitudinal and transverse plasmonic modes simultaneously, and achieve giant enhancement of SHG by more than five orders of magnitude in comparison to a bare LN nanocuboid and by about one order of magnitude to the case adopting only single plasmonic resonance. The underlying key physics is that the double-resonance nanoparticle enables greatly enhanced trapping and harvesting of incident FW energy, efficient internal transfer of optical energy from FW to SHW, and much improved power to transport the SHG energy from the nanoparticle to the far-field region. The proposed double-resonance nanostructure can serve as an efficient subwavelength coherent light source through SHG and enable flexible engineering of light-matter inte...

  11. Electron photoemission in plasmonic nanoparticle arrays: analysis of collective resonances and embedding effects

    Science.gov (United States)

    Zhukovsky, Sergei V.; Babicheva, Viktoriia E.; Uskov, Alexander V.; Protsenko, Igor E.; Lavrinenko, Andrei V.

    2014-09-01

    We theoretically study the characteristics of photoelectron emission in plasmonic nanoparticle arrays. Nanoparticles are partially embedded in a semiconductor, forming Schottky barriers at metal/semiconductor interfaces through which photoelectrons can tunnel from the nanoparticle into the semiconductor; photodetection in the infrared range, where photon energies are below the semiconductor band gap (insufficient for band-to-band absorption in semiconductor), is therefore possible. The nanoparticles are arranged in a sparse rectangular lattice so that the wavelength of the lattice-induced Rayleigh anomalies can overlap the wavelength of the localized surface plasmon resonance of the individual particles, bringing about collective effects from the nanoparticle array. Using full-wave numerical simulations, we analyze the effects of lattice constant, embedding depth, and refractive index step between the semiconductor layer and an adjacent transparent conductive oxide layer. We show that the presence of refractive index mismatch between media surrounding the nanoparticles disrupts the formation of a narrow absorption peak associated with the Rayleigh anomaly, so the role of collective lattice effects in the formation of plasmonic resonance is diminished. We also show that 5-20 times increase of photoemission can be achieved on embedding of nanoparticles without taking into account dynamics of ballistic electrons. The results obtained can be used to increase efficiency of plasmon-based photodetectors and photovoltaic devices. The results may provide clues to designing an experiment where the contributions of surface and volume photoelectric effects to the overall photocurrent would be defined.

  12. Fabrication of plasmonic AgBr/Ag nanoparticles-sensitized TiO2 nanotube arrays and their enhanced photo-conversion and photoelectrocatalytic properties

    Science.gov (United States)

    Wang, Qingyao; Qiao, Jianlei; Jin, Rencheng; Xu, Xiaohui; Gao, Shanmin

    2015-03-01

    Plasmonic photosensitizer AgBr/Ag nanospheres supported on TiO2 nanotube arrays (TiO2 NTs) are prepared by successive ionic layer adsorption and reaction (SILAR) technique followed by photoreduction methods. The structural and surface morphological properties of AgBr/Ag nanoparticles sensitized TiO2 NTs and their photoelectrochemical performance are investigated and discussed. A detailed formation mechanism of the TiO2 NTs/AgBr/Ag is proposed. The TiO2 NTs/AgBr/Ag exhibit excellent photocurrent and photoelectrocatalytic activities under visible light irradiation. Efficient utilization of solar energy to create electron-hole pairs is attributed to the significant visible light response and surface plasmon resonance of Ag nanoparticles. This finding indicates that the high photosensitivity of the TiO2 NTs-based surface plasmon resonance materials could be applied toward the development of new plasmonic visible-light-sensitive photovoltaic fuel cells and photocatalysts.

  13. Plasmonic modes and extinction properties of a random nanocomposite cylinder

    Energy Technology Data Exchange (ETDEWEB)

    Moradi, Afshin, E-mail: a.moradi@kut.ac.ir [Department of Basic Sciences, Kermanshah University of Technology, Kermanshah, Iran and Department of Nano Science, Institute for Studies in Theoretical Physics and Mathematics (IPM), Tehran (Iran, Islamic Republic of)

    2014-04-15

    We study the properties of surface plasmon-polariton waves of a random metal-dielectric nanocomposite cylinder, consisting of bulk metal embedded with dielectric nanoparticles. We use the Maxwell-Garnett formulation to model the effective dielectric function of the composite medium and show that there exist two surface mode bands. We investigate the extinction properties of the system, and obtain the dependence of the extinction spectrum on the nanoparticles’ shape and concentration as well as the cylinder radius and the incidence angle for both TE and TM polarization.

  14. Three-dimensional cavity nanoantennas with resonant-enhanced surface plasmons as dynamic color-tuning reflectors.

    Science.gov (United States)

    Fan, J R; Wu, W G; Chen, Z J; Zhu, J; Li, J

    2017-03-09

    As plasmonic antennas for surface-plasmon-assisted control of optical fields at specific frequencies, metallic nanostructures have recently emerged as crucial optical components for fascinating plasmonic color engineering. Particularly, plasmonic resonant nanocavities can concentrate lightwave energy to strongly enhance light-matter interactions, making them ideal candidates as optical elements for fine-tuning color displays. Inspired by the color mixing effect found on butterfly wings, a new type of plasmonic, multiresonant, narrow-band (the minimum is about 45 nm), high-reflectance (the maximum is about 95%), and dynamic color-tuning reflector is developed. This is achieved from periodic patterns of plasmonic resonant nanocavities in free-standing capped-pillar nanostructure arrays. Such cavity-coupling structures exhibit multiple narrow-band selective and continuously tunable reflections via plasmon standing-wave resonances. Consequently, they can produce a variety of dark-field vibrant reflective colors with good quality, strong color signal and fine tonal variation at the optical diffraction limit. This proposed multicolor scheme provides an elegant strategy for realizing personalized and customized applications in ultracompact photonic data storage and steganography, colorimetric sensing, 3D holograms and other plasmon-assisted photonic devices.

  15. Long-range surface plasmon resonance and surface-enhanced Raman scattering on X-shaped gold plasmonic nanohole arrays.

    Science.gov (United States)

    Hou, Chao; Galvan, Daniel David; Meng, Guowen; Yu, Qiuming

    2017-09-13

    A multilayered architecture including a thin Au film supporting an X-shaped nanohole array and a thick continuous Au film separated by a Cytop dielectric layer is reported in this work. Long-range surface plasmon resonance (LR-SPR) was generated at the top Au/water interface, which also resulted in a long-range surface-enhanced Raman scattering (LR-SERS) effect. LR-SPR originates from the coupling of surface plasmons (SPs) propagating along the opposite sides of the thin Au film embedded in a symmetric refractive index environment with Cytop (n = 1.34) and water (n = 1.33). The finite-difference time-domain (FDTD) simulation method was used to investigate the optimal dimensions of the substrate by studying the reflectance spectra and electric field profiles. The calculated optimal structure was then fabricated via electron beam lithography, and its LR-SERS performance was demonstrated by detecting rhodamine 6G and 4-mercaptobenzoic acid in the refractive index-matched environment. We believe that this structure as a LR-SPR or LR-SERS substrate can have broad applications in biosensing.

  16. Surface plasmon resonance scattered by a dielectric sphere

    Science.gov (United States)

    Hong, Xin; Yin, Xuejie

    2016-11-01

    It is well known that when total internal reflection occurs at the interface between high to low refractive index, evanescent field will go into the media with low refractive index. This field can be scattered by a small dielectric particle on the surface. In this paper, with the aim to enhance the scattering field we introduced a thin gold film, the filed modified by the metallic film was theoretically calculated by FDTD solver. Further a polystyrene bead at the diameter of 200nm and 800nm was employed to test the model. Theoretical and experimental results agree well with each other that the locally excitated surface plasmon play a dominant role in the field enhancement scattered by the sphere.

  17. Near-Field Resonance at Far-Field Anti-Resonance: Plasmonically Enhanced Light Emission with Minimum Scattering Nanoantennas

    CERN Document Server

    Rodriguez, S R K; Lozano, G; Omari, A; Hens, Z; Rivas, J Gomez

    2012-01-01

    We demonstrate that a periodic array of optical antennas sustains a resonant Near-Field (NF) and an anti-resonant Far-Field (FF) at the same energy and in-plane momentum. This phenomenon arises in the context of coupled plasmonic lattice resonances, whose bright and dark character is interchanged at a critical antenna length. The energies of these modes anti-cross in the FF, but cross in the NF. Hence, we observe an extremely narrow bandwidth emission enhancement from quantum dots in the proximity of the array, while the antennas scatter minimally into the FF. Simulations reveal that a standing wave with a quadrupolar field distribution is the origin of this dark collective resonance.

  18. A Novel Fiber Optic Surface Plasmon Resonance Biosensors with Special Boronic Acid Derivative to Detect Glycoprotein

    Directory of Open Access Journals (Sweden)

    Yang Zhang

    2017-10-01

    Full Text Available We proposed and demonstrated a novel tilted fiber Bragg grating (TFBG-based surface plasmon resonance (SPR label-free biosensor via a special boronic acid derivative to detect glycoprotein with high sensitivity and selectivity. TFBG, as an effective sensing element for optical sensing in near-infrared wavelengths, possess the unique capability of easily exciting the SPR effect on fiber surface which coated with a nano-scale metal layer. SPR properties can be accurately detected by measuring the variation of transmitted spectra at optical communication wavelengths. In our experiment, a 10° TFBG coated with a 50 nm gold film was manufactured to stimulate SPR on a sensor surface. To detect glycoprotein selectively, the sensor was immobilized using designed phenylboronic acid as the recognition molecule, which can covalently bond with 1,2- or 1,3-diols to form five- or six-membered cyclic complexes for attaching diol-containing biomolecules and proteins. The phenylboronic acid was synthetized with long alkyl groups offering more flexible space, which was able to improve the capability of binding glycoprotein. The proposed TFBG-SPR sensors exhibit good selectivity and repeatability with a protein concentration sensitivity up to 2.867 dB/ (mg/mL and a limit of detection (LOD of 15.56 nM.

  19. An integrated microfluidic biosensor for the rapid screening of foodborne pathogens by surface plasmon resonance imaging

    Science.gov (United States)

    Zordan, Michael D.; Grafton, Meggie M. G.; Leary, James F.

    2011-03-01

    The rapid detection of foodborne pathogens is of vital importance to keep the food supply rid of contamination. Previously we have demonstrated the design of a hybrid optical device that performs real-time surface plasmon resonance (SPR) and epi-fluorescence imaging. Additionally we have developed a biosensor array chip that is able to specifically detect the presence of two known pathogens. This biosensor detects the presence of the pathogen strains by the selective capture of whole pathogens by peptide ligands functionalized to the spots of the array. We have incorporated this biosensor array into a self contained PDMS microfluidic chip. The enclosure of the biosensor array by a PDMS microfluidic chip allows for a sample to be screened for many strains of pathogens simultaneously in a safe one time use biochip. This disposable optical biochip is inserted into with the hybrid SPR/epi-fluorescence imaging device to form an integrated system for the detection of foodborne pathogens. Using this integrated system, we can selectively detect the presence of E. coli 0157:H7 or S. enterica in a simultaneously in real-time. Additionally, we have modeled the mechanical properties of the microfluidic biochip in order to manipulate the flow conditions to achieve optimal pathogen capture by the biosensor array. We have developed an integrated system that is able to screen a sample for multiple foodborne pathogens simultaneously in a safe, rapid and label-free manner.

  20. An innovative application of time-domain spectroscopy on localized surface plasmon resonance sensing

    Science.gov (United States)

    Li, Meng-Chi; Chang, Ying-Feng; Wang, Huai-Yi; Lin, Yu-Xen; Kuo, Chien-Cheng; Annie Ho, Ja-An; Lee, Cheng-Chung; Su, Li-Chen

    2017-03-01

    White-light scanning interferometry (WLSI) is often used to study the surface profiles and properties of thin films because the strength of the technique lies in its ability to provide fast and high resolution measurements. An innovative attempt is made in this paper to apply WLSI as a time-domain spectroscopic system for localized surface plasmon resonance (LSPR) sensing. A WLSI-based spectrometer is constructed with a breadboard of WLSI in combination with a spectral centroid algorithm for noise reduction and performance improvement. Experimentally, the WLSI-based spectrometer exhibits a limit of detection (LOD) of 1.2 × 10-3 refractive index units (RIU), which is better than that obtained with a conventional UV-Vis spectrometer, by resolving the LSPR peak shift. Finally, the bio-applicability of the proposed spectrometer was investigated using the rs242557 tau gene, an Alzheimer’s and Parkinson’s disease biomarker. The LOD was calculated as 15 pM. These results demonstrate that the proposed WLSI-based spectrometer could become a sensitive time-domain spectroscopic biosensing platform.

  1. Selective excitation of bright and dark plasmonic resonances of single gold nanorods

    CERN Document Server

    Demichel, O; Francs, G Colas des; Bouhelier, A; Hertz, E; Billard, F; de Fornel, F; Cluzel, B

    2015-01-01

    Plasmonic dark modes are pure near-field resonances since their dipole moments are vanishing in far field. These modes are particularly interesting to enhance nonlinear light-matter interaction at the nanometer scale because radiative losses are mitigated therefore increasing the intrinsic lifetime of the resonances. However, the excitation of dark modes by standard far field approaches is generally inefficient because the symmetry of the electromagnetic near-field distribution has a poor overlap with the excitation field. Here, we demonstrate the selective optical excitation of bright and dark plasmonic modes of single gold nanorods by spatial phase-shaping the excitation beam. Using two-photon luminescence measurements, we unambiguously identify the symmetry and the order of the emitting modes and analyze their angular distribution by Fourier-space imaging.

  2. A polarization-sensitive mid-infrared plasmonic absorber for multi-band resonance

    Science.gov (United States)

    Li, Yongqian; Wang, Binbin; Xu, Xiaolun; Su, Lei; Zhou, Zili

    2014-05-01

    The aim of this work is to present a multi-band absorption metamaterials. One dual cross-shape perfect absorber metamaterials (PAMs) was developed to obtain multi-band spectrum at mid-infrared. The PAMs possess three distinct resonant peaks standing independently, which are attributed to the polarization sensitive excitation of plasmonic resonance. The optical parameters retrieved by S-parameters method were investigated, which provides a satisfactory qualitative description of the multiple-band spectra responses. On the other hand, the near-field plasmonic behaviors and redistribution of the electromagnetic field were probed theoretically and numerically into the PAMs structure, which also explains the observed absorption behavior of the PAMs ensemble based upon the microscopic perspective. The multiplex spectrum enables the infrared perfect absorber metamaterials (PAMs) a powerful tool for direct access to vibrational fingerprints of single molecular structure.

  3. Electrically Controlled Plasmonic Lasing Resonances with Silver Nanoparticles Embedded in Amplifying Nematic Liquid Crystals

    CERN Document Server

    Wang, Chin

    2014-01-01

    We demonstrate an electrically controlled coherent random lasing with silver nano-particles dispersed in a dye-doped nematic liquid crystal (NLC), in which external electric field dependent emission intensity and frequency-splitting are recorded. A modified rate equation model is proposed to interpret the observed coherent lasing, which is a manifestation of double enhancements, caused by the plasmon-polariton near-fields of Ag particles, on the population inversion of laser dye molecules and the optical energy density of lasing modes. The noticeable quenching of lasing resonances in a weak applied field is due to the dynamic light scattering by irregular director fluctuations of the NLC host, which wash out the coherent interference among different particle palsmon-polariton fields. This provides a proof to support that the present lasing resonances are very sensitive to the dielectric perturbations in the host medium and thus are likely associated with some coupled plasmonic oscillations of metal nanopartic...

  4. A time-dependent density functional theory investigation of plasmon resonances of linear Au atomic chains

    Institute of Scientific and Technical Information of China (English)

    Liu Dan-Dan; Zhang Hong

    2011-01-01

    We report theoretical studies on the plasmon resonances in linear Au atomic chains by using ab initio timedependent density functional theory. The dipole responses are investigated each as a function of chain length. They converge into a single resonance in the longitudinal mode but split into two transverse modes. As the chain length increases,the longitudinal plasmon mode is redshifted in energy while the transverse modes shift in the opposite direction (blueshifts). In addition,the energy gap between the two transverse modes reduces with chain length increasing. We find that there are unique characteristics,different from those of other metallic chains. These characteristics are crucial to atomic-scale engineering of single-molecule sensing,optical spectroscopy,and so on.

  5. Dependence of fluorescence intensity on the spectral overlap between fluorophores and plasmon resonant single silver nanoparticles.

    Science.gov (United States)

    Chen, Yeechi; Munechika, Keiko; Ginger, David S

    2007-03-01

    We investigate the fluorescence from dyes coupled to individual DNA-functionalized metal nanoparticles. We use single-particle darkfield scattering and fluorescence microscopy to correlate the fluorescence intensity of the dyes with the localized surface plasmon resonance (LSPR) spectra of the individual metal nanoparticles to which they are attached. For each of three different dyes, we observe a strong correlation between the fluorescence intensity of the dye and the degree of spectral overlap with the plasmon resonance of the nanoparticle. On average, we observe the brightest fluorescence from dyes attached to metal nanoparticles that have a LSPR scattering peak approximately 40-120 meV higher in energy than the emission peak of the fluorophore. These results should prove useful for understanding and optimizing metal-enhanced fluorescence.

  6. Strong Modulation of Infrared Light using Graphene Integration with Plasmonic Fano-Resonant Metasurfaces

    CERN Document Server

    Dabidian, Nima; Khanikaev, Alexander B; Tatar, Kaya; Trendafilov, Simeon; Mousavi, S Hossein; Magnuson, Carl; Ruoff, Rodney S; Shvets, Gennady

    2014-01-01

    Plasmonic metasurfaces represent a promising platform for enhancing light-matter interaction. Active control of the optical response of metasurfaces is desirable for applications such as beam-steering, modulators and switches, biochemical sensors, and compact optoelectronic devices. Here we use a plasmonic metasurface with two Fano resonances to enhance the interaction of infrared light with electrically controllable single layer graphene. It is experimentally shown that the narrow spectral width of these resonances, combined with strong light/graphene coupling, enables reflectivity modulation by nearly an order of magnitude leading to a modulation depth as large as 90%. . Numerical simulations demonstrate the possibility of strong active modulation of the phase of the reflected light while keeping the reflectivity nearly constant, thereby paving the way to tunable infrared lensing and beam steering

  7. Surface plasmon resonance hydrogen sensor based on metallic grating with high sensitivity.

    Science.gov (United States)

    Lin, Kaiqun; Lu, Yonghua; Chen, Junxue; Zheng, Rongsheng; Wang, Pei; Ming, Hai

    2008-11-10

    High sensitivity is obtained at larger resonant incident angle if negative diffraction order of metallic grating is used to excite the surface plasmon. A highly sensitive grating-based surface plasmon resonance (SPR) sensor is designed for the hydrogen detection. A thin palladium (Pd) film deposited on the grating surface is used as transducer. The influences of grating period and the thickness of Pd on the performance of sensor are investigated using rigorous coupled-wave analysis (RCWA) method. The sensitivity as well as the width of the SPR curves and reflective amplitude is considered simultaneously for designing the grating-based SPR hydrogen sensor, and a set of optimized structural parameters is presented. The performance of grating-based SPR sensor is also compared with that of conventional prism-based SPR sensor.

  8. Profile Prediction and Fabrication of Wet-Etched Gold Nanostructures for Localized Surface Plasmon Resonance

    Directory of Open Access Journals (Sweden)

    Zhou Xiaodong

    2009-01-01

    Full Text Available Abstract Dispersed nanosphere lithography can be employed to fabricate gold nanostructures for localized surface plasmon resonance, in which the gold film evaporated on the nanospheres is anisotropically dry etched to obtain gold nanostructures. This paper reports that by wet etching of the gold film, various kinds of gold nanostructures can be fabricated in a cost-effective way. The shape of the nanostructures is predicted by profile simulation, and the localized surface plasmon resonance spectrum is observed to be shifting its extinction peak with the etching time. (See supplementary material 1 Electronic supplementary material The online version of this article (doi:10.1007/s11671-009-9486-4 contains supplementary material, which is available to authorized users. Click here for file

  9. Design optimization of highly sensitive LSPR enhanced surface plasmon resonance biosensors with nanoholes

    Institute of Scientific and Technical Information of China (English)

    Bin Wu; Qingkang Wang

    2008-01-01

    For breaking through the sensitivity limitation of conventional surface plasmon resonance (SPR) biosensors, novel highly sensitive SPR biosensors with Au nanoparticles and nanogratings enhancement have been proposed recently.But in practice, these structures have obvious disadvantages.In this study, a nanohole based sensitivity enhancement SPR biosensor is proposed and the influence of different structural parameters on the performance is investigated by using rigorous coupled wave analysis (RCWA).Electromagnetic field distributions around the nanohole are also given out to directly explain the performance difference for various structural parameters.The results indicate that significant sensitivity increase is associated with localized surface plasmons (LSPs) excitation mediated by nanoholes.Except to outcome the weakness of other LSP based biosensors, larger resonance angle shift, reflectance amplitude, and sharper SPR curves' width are obtained simultaneously under optimized structural parameters.

  10. Microfluidic Surface Plasmon Resonance Sensors: From Principles to Point-of-Care Applications.

    Science.gov (United States)

    Wang, Da-Shin; Fan, Shih-Kang

    2016-07-27

    Surface plasmon resonance (SPR) is a label-free, highly-sensitive, and real-time sensing technique. Conventional SPR sensors, which involve a planar thin gold film, have been widely exploited in biosensing; various miniaturized formats have been devised for portability purposes. Another type of SPR sensor which utilizes localized SPR (LSPR), is based on metal nanostructures with surface plasmon modes at the structural interface. The resonance condition is sensitive to the refractive index change of the local medium. The principles of these two types of SPR sensors are reviewed and their integration with microfluidic platforms is described. Further applications of microfluidic SPR sensors to point-of-care (POC) diagnostics are discussed.

  11. Compact on-Chip Temperature Sensors Based on Dielectric-Loaded Plasmonic Waveguide-Ring Resonators

    Directory of Open Access Journals (Sweden)

    Sergey I. Bozhevolnyi

    2011-02-01

    Full Text Available The application of a waveguide-ring resonator based on dielectric-loaded surface plasmon-polariton waveguides as a temperature sensor is demonstrated in this paper and the influence of temperature change to the transmission through the waveguide-ring resonator system is comprehensively analyzed. The results show that the roundtrip phase change in the ring resonator due to the temperature change is the major reason for the transmission variation. The performance of the temperature sensor is also discussed and it is shown that for a waveguide-ring resonator with the resonator radius around 5 mm and waveguide-ring gap of 500 nm which gives a footprint around 140 µm2, the temperature sensitivity at the order of 10−2 K can be achieved with the input power of 100 mW within the measurement sensitivity limit of a practical optical detector.

  12. Efficient suppression of radiation damping in individual plasmonic resonators: towards high-Q nano-volume sensing

    DEFF Research Database (Denmark)

    Della Valle, G.; Bozhevolnyi, S. I.

    2012-01-01

    Recent results on radiation damping suppression in individual plasmonic resonators using conformal bending of the structure, which suppresses the electric-dipole response in favor of magnetic dipole one, are overviewed. It is demonstrated that bending of linear plasmonic nano-antennas increases...... significantly their Q factors above the electrostatic limit while preserving the nature of resonance along with its exceptional features, such as linear size-dependent tunability and robust field enhancement. The approach, which makes use of strong lateral confinement exhibited by the slow plasmonic modes (slow...

  13. Quantitative modelling of the surface plasmon resonances of metal nanoclusters sandwiched between dielectric layers: the influence of nanocluster size, shape and organization

    Energy Technology Data Exchange (ETDEWEB)

    Toudert, J; Babonneau, D; Simonot, L; Camelio, S; Girardeau, T [PHYMAT, UMR CNRS 6630, Batiment SP2MI, Boulevard Marie et Pierre Curie, 86962 Futuroscope Chasseneuil (France)], E-mail: johann.toudert@gmail.com

    2008-03-26

    The effects of size, shape and organization on the surface plasmon resonances of Ag nanoclusters sandwiched between Si{sub 3}N{sub 4} layers are studied by transmission electron microscopy and anisotropic spectroscopic ellipsometry. We present an easy-to-handle model that quantitatively links the nanostructure and optical response of the films, which are considered as dielectric/metal:dielectric/dielectric trilayers, with the central nanocomposite layer being an effective medium whose optical properties are described by an anisotropic dielectric tensor. The components of this tensor are calculated using a generalization of the Yamaguchi theory taking into account the real organization, size and shape distributions of ellipsoidal nanoclusters, whose electronic properties are assumed to reflect shape-dependent finite size effects. Using this model, it is shown that the optical response of the films in the visible range is dominated by the excitation of the surface plasmon resonance of the clusters along their in-plane long axis, while no surface plasmon resonance resulting from an excitation along their in-plane short axis can be observed due to damping effects. Moreover, the spectral position of this resonance appears to be mainly affected by the average shape of the clusters, and weakly by their size, their shape distribution and the electromagnetic interaction between them.

  14. Multilayered core-satellite nanoassemblies with fine-tunable broadband plasmon resonances

    Science.gov (United States)

    Xiong, Wei; Sikdar, Debabrata; Yap, Lim Wei; Premaratne, Malin; Li, Xinyong; Cheng, Wenlong

    2015-02-01

    We report on a robust nanotemplating approach to synthesize plasmonic multilayered core-satellite (MCS) nanoassemblies. Templated with gold nanorods, ultrathin Au/Ag alloy cages and satellite gold nanoparticles can be constructed sequentially by galvanic replacement reactions and electrostatic self-assembly, respectively, forming structurally well-defined MCS. The MCS nanoassemblies exhibit strong broadband plasmon resonances from ~440 to ~1100 nm, and their resonant features can be fine-tuned by adjusting the size and number density of satellite nanoparticles and by adjusting the thickness of the silica spacer between cage and satellite particles. Such fine-engineered MCS nanoassemblies enable precise programming of the strength and distribution of ``hot spots'' to maximize the overall enhancement of surface enhanced Raman scattering.We report on a robust nanotemplating approach to synthesize plasmonic multilayered core-satellite (MCS) nanoassemblies. Templated with gold nanorods, ultrathin Au/Ag alloy cages and satellite gold nanoparticles can be constructed sequentially by galvanic replacement reactions and electrostatic self-assembly, respectively, forming structurally well-defined MCS. The MCS nanoassemblies exhibit strong broadband plasmon resonances from ~440 to ~1100 nm, and their resonant features can be fine-tuned by adjusting the size and number density of satellite nanoparticles and by adjusting the thickness of the silica spacer between cage and satellite particles. Such fine-engineered MCS nanoassemblies enable precise programming of the strength and distribution of ``hot spots'' to maximize the overall enhancement of surface enhanced Raman scattering. Electronic supplementary information (ESI) available: A method for preparing CGNRs and AuNPs. EDX mapping and UV-vis spectra for silica coated CGNR. A model for simulation and an additional E-field for MCS nanoassemblies. See DOI: 10.1039/c4nr06756h

  15. Increase in sensitivity of sensor units of environment refraction index change based on superficial plasmon resonance

    Directory of Open Access Journals (Sweden)

    Ushenin Yu. V.

    2011-04-01

    Full Text Available Results of computer modeling of an angular spectrum superficial plasmon resonance in metal films measurements with device PLAZMON-5 with infra-red radiator are analysed. It is shown that use of an infra-red source of radiation allows to improve sensitivity of sensor device in comparison with source of visible light. On an example of dielectric refraction indexes measurement with PLAZMON-5 device experimental check of theoretical calculations has been carried out.

  16. Quantum Rod Emission Coupled to Plasmonic Lattice Resonances: A Collective Directional Source of Polarized Light

    CERN Document Server

    Rodriguez, S R K; Verschuuren, M A; Gomes, R; Lambert, K; De Geyter, B; Hassinen, A; Van Thourhout, D; Hens, Z; Rivas, J Gomez

    2013-01-01

    We demonstrate that an array of optical antennas may render a thin layer of randomly oriented semiconductor nanocrystals into an enhanced and highly directional source of polarized light. The array sustains collective plasmonic lattice resonances which are in spectral overlap with the emission of the nanocrystals over narrow angular regions. Consequently, di?fferent photon energies of visible light are enhanced and beamed into def?nite directions.

  17. Long-wave approximation for hybridization modeling of local surface plasmonic resonance in nanoshells.

    Science.gov (United States)

    Li, Ben Q; Liu, Changhong

    2011-01-15

    A hybridization model for the localized surface plasmon resonance of a nanoshell is developed within the framework of long-wave approximation. Compared with the existing hybridization model derived from the hydrodynamic simulation of free electron gas, this approach is much simpler and gives identical results for a concentric nanoshell. Also, with this approach, the limitations associated with the original hybridization model are succinctly stated. Extension of this approach to hybridization modeling of more complicated structures such as multiplayered nanoshells is straightforward.

  18. Cavitands: Container Molecules for Surface Plasmon Resonance (SPR)-Based Chemical Vapor Detection

    Science.gov (United States)

    2005-01-01

    spin coated onto surface plasmon resonance substrates (50-nm thick gold-coated cover glass). Spin coating was performed at 4000 rpm for 60 s at...room temperature. Th e spin coating parameters gave a fi lm thickness (confi rmed using spectroscopic ellipsometry) of nearly 4 nm. For targets, a...fact that the polymer fi lms were about twice as thick as the cavitand fi lms obtained under identical spin - coating conditions. Th is clearly

  19. Polarization dependence of the metamagnetic resonance of cut-wire-pair structure by using plasmon hybridization

    Energy Technology Data Exchange (ETDEWEB)

    Dung, Nguyen Van; Yoo, Young Joon; Lee, Young Pak [Hanyang University, Seoul (Korea, Republic of); Tung, Nguyen Thanh [KU Leuven, Leuven (Belgium); Tung, Bui Son; Lam, Vu Dinh [Vietnam Academy of Science and Technology, Hanoi (Viet Nam)

    2014-07-15

    The influence of lattice constants on the electromagnetic behavior of a cut-wire-pair (CWP) structure has been elucidated. In this report, we performed both simulations and experiments to determine the influence of polarization on the metamagnetic resonance of the CWP structure. The key finding is the result of an investigation on the plasmon hybridization between the two CWs, which showed that the polarization of the incident wave was affected. Good agreement between numerical simulation and measurement is achieved.

  20. Surface Functionalization for Enhanced Fluorescence Detection, Surface Plasmon Resonance Imaging and Microscopy

    OpenAIRE

    Fasoli, Jennifer Betsy

    2015-01-01

    This work presents several high throughput imaging and analysis techniques performed by fluorescence detection and surface plasmon resonance biosensing. The microarray fabrication methods introduced in this thesis, as well as the DNA functionalization on planar and nanoparticle surfaces, enable and facilitate the real-time study of adsorption events via DNA- DNA hybridization and protein-DNA interaction. Silica deposited on polyolefin film serves as the base for the development of DNA mic...

  1. Fabrication of discrete array of metallodielectric nanoshells and their surface plasmonic properties

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, Shuhei; Yamamura, Kazuya [Research Center for Ultra-Precision Science and Technology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita Osaka 565-0871 (Japan); Zettsu, Nobuyuki, E-mail: zettsu@upst.eng.osaka-u.ac.j [Research Center for Ultra-Precision Science and Technology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita Osaka 565-0871 (Japan)

    2010-04-30

    In this paper we describe the fabrication of two-dimensionally periodic non-close-packed nanoshell arrays, consisting of a spherical polystyrene core coated with a thin gold shell, as well as their surface plasmonic properties. The principle of this procedure relies on stepwise integration of spin-coat-assisted colloidal self-assembly of the single layer of close-packed polystyrene nanoparticle, atmospheric pressure plasma-induced isotropic etching, and deposition of gold thin film by thermal evaporation. The plasma process converted the close-packed nanoparticle array into non-close-packed arrangement without changing their original spherical shape and periodicity. Both experimental and theoretical studies revealed that the densely packed nanoshell array with a 160 nm inner core diameter and a 20 nm thick shell strongly scattered and absorbed near infrared light, due to the interaction between primitive plasmon modes associated with the surface of the nanoparticle. Furthermore, the resultant nanoshell array was utilized for near infrared light responsible localized surface plasmon resonance based sensor. The bulk refractive index sensitivity was 220 nm RIU{sup -1}.

  2. Surface plasmon enhanced interfacial electron transfer and resonance Raman, surface-enhanced resonance Raman studies of cytochrome C mutants

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Junwei

    1999-11-08

    Surface plasmon resonance was utilized to enhance the electron transfer at silver/solution interfaces. Photoelectrochemical reductions of nitrite, nitrate, and CO{sub 2} were studied on electrochemically roughened silver electrode surfaces. The dependence of the photocurrent on photon energy, applied potential and concentration of nitrite demonstrates that the photoelectrochemical reduction proceeds via photoemission process followed by the capture of hydrated electrons. The excitation of plasmon resonances in nanosized metal structures resulted in the enhancement of the photoemission process. In the case of photoelectrocatalytic reduction of CO{sub 2}, large photoelectrocatalytic effect for the reduction of CO{sub 2} was observed in the presence of surface adsorbed methylviologen, which functions as a mediator for the photoexcited electron transfer from silver metal to CO{sub 2} in solution. Photoinduced reduction of microperoxidase-11 adsorbed on roughened silver electrode was also observed and attributed to the direct photoejection of free electrons of silver metal. Surface plasmon assisted electron transfer at nanostructured silver particle surfaces was further determined by EPR method.

  3. Surface plasmon enhanced interfacial electron transfer and resonance Raman, surface-enhanced resonance Raman studies of cytochrome C mutants

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Junwei [Iowa State Univ., Ames, IA (United States)

    1999-11-08

    Surface plasmon resonance was utilized to enhance the electron transfer at silver/solution interfaces. Photoelectrochemical reductions of nitrite, nitrate, and CO2 were studied on electrochemically roughened silver electrode surfaces. The dependence of the photocurrent on photon energy, applied potential and concentration of nitrite demonstrates that the photoelectrochemical reduction proceeds via photoemission process followed by the capture of hydrated electrons. The excitation of plasmon resonances in nanosized metal structures resulted in the enhancement of the photoemission process. In the case of photoelectrocatalytic reduction of CO2, large photoelectrocatalytic effect for the reduction of CO2 was observed in the presence of surface adsorbed methylviologen, which functions as a mediator for the photoexcited electron transfer from silver metal to CO2 in solution. Photoinduced reduction of microperoxidase-11 adsorbed on roughened silver electrode was also observed and attributed to the direct photoejection of free electrons of silver metal. Surface plasmon assisted electron transfer at nanostructured silver particle surfaces was further determined by EPR method.

  4. Atomically localized plasmon enhancement in monolayer graphene

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Wu [Vanderbilt University; Lee, Jaekwang [Vanderbilt University; Nanda, Jagjit [ORNL; Pantelides, Sokrates T. [Vanderbilt University; Pennycook, Stephen J [ORNL; Idrobo Tapia, Juan C [ORNL

    2012-01-01

    Plasmons in graphene can be tuned by using electrostatic gating or chemical doping, and the ability to confine plasmons in very small regions could have applications in optoelectronics, plasmonics and transformation optics. However, little is known about how atomic-scale defects influence the plasmonic properties of graphene. Moreover, the smallest localized plasmon resonance observed in any material to date has been limited to around 10 nm. Here, we show that surface plasmon resonances in graphene can be enhanced locally at the atomic scale. Using electron energy-loss spectrum imaging in an aberration-corrected scanning transmission electron microscope, we find that a single point defect can act as an atomic antenna in the petahertz (10{sup 15} Hz) frequency range, leading to surface plasmon resonances at the subnanometer scale.

  5. Magneto-optical plasmonic heterostructure with ultranarrow resonance for sensing applications

    Science.gov (United States)

    Ignatyeva, Daria O.; Knyazev, Grigory A.; Kapralov, Pavel O.; Dietler, Giovanni; Sekatskii, Sergey K.; Belotelov, Vladimir I.

    2016-06-01

    Currently, sensors invade into our everyday life to bring higher life standards, excellent medical diagnostic and efficient security. Plasmonic biosensors demonstrate an outstanding performance ranking themselves among best candidates for different applications. However, their sensitivity is still limited that prevents further expansion. Here we present a novel concept of magnetoplasmonic sensor with ultranarrow resonances and high sensitivity. Our approach is based on the combination of a specially designed one-dimensional photonic crystal and a ferromagnetic layer to realize ultralong-range propagating magnetoplasmons and to detect alteration of the environment refractive index via observation of the modifications in the Transversal Magnetooptical Kerr Effect spectrum. The fabrication of such a structure is relatively easy in comparison with e.g. nanopatterned samples. The fabricated heterostructure shows extremely sharp (angular width of 0.06°) surface plasmon resonance and even sharper magnetoplasmonic resonance (angular width is 0.02°). It corresponds to the propagation length as large as 106 μm which is record for magnetoplasmons and promising for magneto-optical interferometry and plasmonic circuitry as well as magnetic field sensing. The magnitude of the Kerr effect of 11% is achieved which allows for detection limit of 1•10-6. The prospects of further increase of the sensitivity of this approach are discussed.

  6. Colorimetric determination of Timolol concentration based on localized surface plasmon resonance of silver nanoparticles

    Science.gov (United States)

    Amirjani, Amirmostafa; Bagheri, Mozhgan; Heydari, Mojgan; Hesaraki, Saeed

    2016-09-01

    In this work, a rapid and simple colorimetric method based on the surface plasmon resonance of silver nanoparticles (AgNPs) was developed for the detection of the drug Timolol. The method used is based on the interaction of Timolol with the surface of the as-synthesized AgNPs, which promotes aggregation of the nanoparticles. This aggregation exploits the surface plasmon resonance through the electric dipole-dipole interaction and coupling among the agglomerated particles, hence bringing forth distinctive changes in the spectra as well as the color of colloidal silver. UV-vis spectrophotometery was used to monitor the changes of the localized surface plasmon resonance of AgNPs at wavelengths of 400 and 550 nm. The developed colorimetric sensor has a wide dynamic range of 1.0 × 10-7 M-1.0 × 10-3 M for detection of Timolol with a low detection limit of 1.2 × 10-6 M. The proposed method was successfully applied for the determination of Timolol concentration in ophthalmic eye-drop solution with a response time lower than 40 s.

  7. Plasmon resonance in new AsSb–AlGaAs metal–semiconductor metamaterials

    Energy Technology Data Exchange (ETDEWEB)

    Ushanov, V. I., E-mail: ushanovvi@mail.ioffe.ru; Chaldyshev, V. V., E-mail: chald.gvg@mail.ioffe.ru; Bert, N. A.; Nevedomsky, V. N.; Il’inskaya, N. D.; Lebedeva, N. M. [Russian Academy of Sciences, Ioffe Institute (Russian Federation); Preobrazhenskii, V. V.; Putyato, M. A.; Semyagin, B. R. [Russian Academy of Sciences, Institute of Semiconductor Physics, Siberian Branch (Russian Federation)

    2015-12-15

    Optical extinction in a metal–semiconductor metamaterial based on a AlGaAs matrix, which contains random arrays of AsSb plasmon nanoinclusions, is studied. The metamaterial is grown by molecular beam epitaxy at a low temperature. A system of nanoinclusions of various sizes is formed by annealing at temperatures 400, 500, and 600°C. Investigation of the sample’s microstructure by transmission electron microscopy shows that the average size of nanoinclusions at the used annealing temperatures is 4–7, 5–8, and 6–9 nm, respectively. It is shown experimentally that AsSb nanoparticle arrays in the AlGaAs matrix cause the resonant absorption of light. It is established that the plasmon-resonance parameters found in the metamaterial are almost independent of the sizes of the AsSb nanoinclusions. The plasmon-resonance energy is (1.47 ± 0.01) eV, while its full width at half maximum is (0.19 ± 0.01) eV.

  8. [Spectra modulated surface plasmon resonance sensor based on side polished multi-mode optical fiber].

    Science.gov (United States)

    Luo, Yun-Han; Chen, Xiao-Long; Xu, Meng-Yun; Ge, Jia; Zhang, Yi-Long; He, Yong-Hong; Tang, Jie-Yuan; Yu, Jian-Hui; Zhang, Jun; Chen, Zhe; Chen, Xing-Dan

    2014-03-01

    Surface plasmon resonance, which utilizes the resonance of optical evanescent wave with the metal surface plasmon wave, has been developed into a high sensitivity, rapid, label-less measurement method for chemical and biological analysis. In order to improve the spectral sensitivity in refractive index for a side polished fiber surface plasmon resonance sensor, the whole cladding layer and part of core of a multimode fiber was polished off. Additionally, an extra chrome layer with relatively high refractive index was coated on the polished zone before a gold film. The results showed that the sensor can measure the refractive index range from 1.333 to 1. 431 RIU, with the average spectral sensitivity of 4.11 x 10(3) nm RIU(-1), which is better than the reported results. Especially, in the refractive index range of 1. 417 1. 431 RIU, the sensitivity reaches to 1.09 x 10(4) nm RIU(-1). The minimum resolution of approximately 3.6 x 10(-5) RIU was estimated by a combination analysis with the sensor sensitivity and stability. The superiorities possessed by the proposed sensor in high sensitivity, wide detection range, small size and good stability and reproducibility, etc., make it a good candidate for food testing, environmental monitoring, biomedical testing and other related fields.

  9. Low-Power Photothermal Probing of Single Plasmonic Nanostructures with Nanomechanical String Resonators

    DEFF Research Database (Denmark)

    Schmid, Silvan; Wu, Kaiyu; Larsen, Peter Emil

    2014-01-01

    We demonstrate the direct photothermal probing and mapping of single plasmonic nanostructures via the temperature-induced detuning of nanomechanical string resonators. Single Au nanoslits and nanorods are illuminated with a partially polarized focused laser beam (λ = 633 nm) with irradiances in t......). Our results show that nanomechanical resonators are a unique and robust analysis tool for the low-power investigation of thermoplasmonic effects in plasmonic hot spots.......We demonstrate the direct photothermal probing and mapping of single plasmonic nanostructures via the temperature-induced detuning of nanomechanical string resonators. Single Au nanoslits and nanorods are illuminated with a partially polarized focused laser beam (λ = 633 nm) with irradiances...... in the range of 0.26–38 μW/μm2. Photothermal heating maps with a resolution of ∼375 nm are obtained by scanning the laser over the nanostructures. Based on the string sensitivities, absorption efficiencies of 2.3 ± 0.3 and 1.1 ± 0.7 are extracted for a single nanoslit (53 nm × 1 μm) and nanorod (75 nm × 185 nm...

  10. Plasmon resonances in linear noble-metal chains

    Science.gov (United States)

    Gao, Bin; Ruud, Kenneth; Luo, Yi

    2012-11-01

    The electronic excitations of three noble-metall chains—copper, silver, and gold—have been investigated at the time-dependent density functional theory level. The reduced single-electron density matrix is propagated according to the Liouville-von Neumann equation in the real-time domain after an impulse excitation. The propagation in the real-time domain enables us to investigate the formation and size evolution of electronic excitations in these metallic chains with different number of atoms, up to a total of 26 atoms. The longitudinal oscillations at lower excitation energies are dominated by s → p transitions in these chains and have collective or central resonances, while the first peak involving d → p transitions in the longitudinal mode appears at a higher excitation energy and shows collective resonances. In the transverse oscillations, there are in most cases d → p transitions in each resonance, which can be attributed to either central or end resonances. Convergence of the oscillations, in particular those involving the collective and central resonances in the three noble-metal chains can only be observed for chains with 18 atoms or more. Different spectroscopic characteristics among these three metallic chains can be attributed to their different electronic structures, in particular the relativistic effects in the gold chains have a dramatic effect on their electronic structures and excitations.

  11. Blueshift of the surface plasmon resonance in silver nanoparticles: substrate effects

    OpenAIRE

    Raza, Søren; Yan, Wei; Stenger, Nicolas; Wubs, Martijn; Mortensen, N. Asger

    2013-01-01

    We study the blueshift of the surface plasmon (SP) resonance energy of isolated Ag nanoparticles with decreasing particle diameter, which we recently measured using electron energy loss spectroscopy (EELS) [1]. As the particle diameter decreases from 26 down to 3.5 nm, a large blueshift of 0.5 eV of the SP resonance energy is observed. In this paper, we base our theoretical interpretation of our experimental findings on the nonlocal hydrodynamic model, and compare the effect of the substrate ...

  12. Electrochemical surface plasmon resonance sensor based on two-electrode configuration

    Science.gov (United States)

    Zhang, Bing; Li, Yazhuo; Dong, Wei; Wen, Yizhang; Pang, Kai; Zhan, Shuyue; Wang, Xiaoping

    2016-10-01

    To obtain detailed information about electrochemistry reactions, a two-electrode electrochemical surface plasmon resonance (EC-SPR) sensor has been proposed. We describe the theory of potential modulation for this novel sensor and determine the factors that can change the SPR resonance angle. The reference electrode in three-electrode configuration was eliminated, and comparing with several other electrode materials, activated carbon (AC) is employed as the suitable counter electrode for its potential stability. Just like three-electrode configuration, the simpler AC two-electrode system can also obtain detailed information about the electrochemical reactions.

  13. Plasmon resonances of Ag capped Si nanopillars fabricated using mask-less lithography

    DEFF Research Database (Denmark)

    Wu, Kaiyu; Rindzevicius, Tomas; Schmidt, Michael Stenbæk;

    2015-01-01

    . The LSPR peak position of the particle mode can be tuned by changing the size of the Ag cap, and can be hybridized by leaning of pillars. The resonance position of the cavity resonance mode can be tuned primarily via the diameter of the Si pillar, and cannot be tuned via leaning of Ag NPs. The presence...... of a substrate dramatically changes the intensity of these two LSPR modes by introducing constructive and destructive interference patterns with incident and reflected fields. Experimental scattering spectra can be interpreted using theoretical simulations. The Ag NP substrate displays a broad plasmonic...

  14. Covellite CuS nanocrystals: realizing rapid microwave-assisted synthesis in air and unravelling the disappearance of their plasmon resonance after coupling with carbon nanotubes

    Science.gov (United States)

    Kim, Mee Rahn; Hafez, Hassan A.; Chai, Xin; Besteiro, Lucas V.; Tan, Long; Ozaki, Tsuneyuki; Govorov, Alexander O.; Izquierdo, Ricardo; Ma, Dongling

    2016-06-01

    . By extracting the rising and relaxation constants through fitting a single-exponential rising function and a bi-exponential relaxation function, in combination with the results of THz differential transmission as a function of the NIR pump fluence, it was found that hole injection changed the electronic properties of the MWCNTs only subtly on a short picosecond time scale, whereas the nature of the band structure of the MWCNTs remained largely unchanged. These findings aid our understanding of recently emerging semiconductor plasmonics and will also help in developing practical applications.Semiconductor nanocrystals that show plasmonic resonance represent an emerging class of highly promising plasmonic materials with potential applications in diverse fields, such as sensing and optical and optoelectronic devices. We report a new approach to synthesizing homogeneous covellite CuS nanoplatelets in air and the almost complete disappearance of their plasmonic resonance once coupled with multiwalled carbon nanotubes (MWCNTs). These nanoplatelets were rapidly synthesized by a simple microwave-assisted approach at a relatively low reaction temperature in air, instead of under N2 as reported previously. These less severe synthesis conditions were enabled by appropriately selecting a Cu precursor and preparing a precursor sulfur solution (instead of using solid sulfur) and by using microwave radiation as the heat source. The advantages of utilizing microwave irradiation, including uniform and rapid heating, became clear after comparing the results of the synthesis with those achieved using a conventional oil-bath method under N2. The CuS nanoplatelets prepared in this way showed very strong plasmon resonance at c. 1160 nm as a result of their free charge carriers at the calculated density of nh = 1.5 × 1022 cm-3 based on the Drude model. With the aim of exploring their potential for near-infrared responsive optoelectronic devices, they were hybridized with functionalized

  15. Plasmon resonance and perfect light absorption in subwavelength trench arrays etched in gallium-doped zinc oxide film

    Energy Technology Data Exchange (ETDEWEB)

    Hendrickson, Joshua R., E-mail: joshua.hendrickson.4@us.af.mil; Leedy, Kevin; Cleary, Justin W. [Air Force Research Laboratory, Sensors Directorate, 2241 Avionics Circle, Wright Patterson AFB, Ohio 45433 (United States); Vangala, Shivashankar [Air Force Research Laboratory, Sensors Directorate, 2241 Avionics Circle, Wright Patterson AFB, Ohio 45433 (United States); SURVICE Engineering, 4141 Colonel Glenn Highway, Dayton, Ohio 45431 (United States); Nader, Nima [Air Force Research Laboratory, Sensors Directorate, 2241 Avionics Circle, Wright Patterson AFB, Ohio 45433 (United States); Solid State Scientific Corporation, 12 Simon St., Nashua, New Hampshire 03060 (United States); Guo, Junpeng [Department of Electrical and Computer Engineering, University of Alabama in Huntsville, 301 Sparkman Drive, Huntsville, Alabama 35899 (United States)

    2015-11-09

    Near-perfect light absorption in subwavelength trench arrays etched in highly conductive gallium-doped zinc oxide films was experimentally observed in the mid infrared regime. At wavelengths corresponding to the resonant excitation of surface plasmons, up to 99% of impinging light is efficiently trapped and absorbed in the periodic trenches. Scattering cross sectional calculations reveal that each individual trench acts like a vertical split ring resonator with a broad plasmon resonance spectrum. The coupling of these individual plasmon resonators in the grating structure leads to enhanced photon absorption and significant resonant spectral linewidth narrowing. Ellipsometry measurements taken before and after device fabrication result in different permittivity values for the doped zinc oxide material, indicating that localized annealing occurred during the plasma etching process due to surface heating. Simulations, which incorporate a 50 nm annealed region at the zinc oxide surface, are in a good agreement with the experimental results.

  16. Molecular resonant dissociation of surface-adsorbed molecules by plasmonic nanoscissors

    Science.gov (United States)

    Zhang, Zhenglong; Sheng, Shaoxiang; Zheng, Hairong; Xu, Hongxing; Sun, Mengtao

    2014-04-01

    The ability to break individual bonds or specific modes in chemical reactions is an ardently sought goal by chemists and physicists. While photochemistry based methodologies are very successful in controlling e.g. photocatalysis, photosynthesis and the degradation of plastic, it is hard to break individual molecular bonds for those molecules adsorbed on the surface because of the weak light-absorption in molecules and the redistribution of the resulting vibrational energy both inside the molecule and to its surrounding environment. Here we show how to overcome these obstacles with a plasmonic hot-electron mediated process and demonstrate a new method that allows the sensitive control of resonant dissociation of surface-adsorbed molecules by `plasmonic' scissors. To that end, we used a high-vacuum tip-enhanced Raman spectroscopy (HV-TERS) setup to dissociate resonantly excited NC2H6 fragments from Malachite green. The surface plasmons (SPs) excited at the sharp metal tip not only enhance the local electric field to harvest the light incident from the laser, but crucially supply `hot electrons' whose energy can be transferred to individual bonds. These processes are resonant Raman, which result in some active chemical bonds and then weaken these bonds, followed by dumping in lots of indiscriminant energy and breaking the weakest bond. The method allows for sensitive control of both the rate and probability of dissociation through their dependence on the density of hot electrons, which can be manipulated by tuning the laser intensity or tunneling current/bias voltage in the HV-TERS setup, respectively. The concepts of plasmonic scissors open up new versatile avenues for the deep understanding of in situ surface-catalyzed chemistry.The ability to break individual bonds or specific modes in chemical reactions is an ardently sought goal by chemists and physicists. While photochemistry based methodologies are very successful in controlling e.g. photocatalysis

  17. Optical characterization of polyethylene and cobalt phthalocyanine ultrathin films by means of the ATR technique at surface plasmon resonance

    Science.gov (United States)

    Rodríguez Juárez, M.; Muñoz Aguirre, N.; Martínez Pérez, L.; Garibay-Febles, V.; Lozada-Cassou, M.; Becerril, M.; Zelaya Angel, O.

    2006-08-01

    It is well known that the development and determination of optical properties of ultrathin films is an important issue in many technological areas. In this work organic polyethylene (PE) and cobalt phthalocyanines (CoPc) ultrathin films were deposited over metal films using the r.f. sputtering and thermal evaporation techniques, respectively. Attenuated total reflection (ATR) measurements for the system organic film/metal at the surface plasmon resonance (SPR) were used for determining the thicknesses and optical properties of the PE and CoPc thin films. Thicknesses of the order of some nanometers were found, fitting the theoretical multilayer ATR model, for p polarization monochromatic light, to the experimental reflection data. The dielectric function of CoPc ultrathin films was determined at a wavelength of 632.8 nm.

  18. Performance Improvement of Polymer Solar Cells by Surface-Energy-Induced Dual Plasmon Resonance.

    Science.gov (United States)

    Yao, Mengnan; Shen, Ping; Liu, Yan; Chen, Boyuan; Guo, Wenbin; Ruan, Shengping; Shen, Liang

    2016-03-09

    The surface plasmon resonance (SPR) effect of metal nanoparticles (MNPs) is effectively applied on polymer solar cells (PSCs) to improve power conversion efficiency (PCE). However, universality of the reported results mainly focused on utilizing single type of MNPs to enhance light absorption only in specific narrow wavelength range. Herein, a surface-energy-induced dual MNP plasmon resonance by thermally evaporating method was presented to achieve the absorption enhancement in wider range. The differences of surface energy between silver (Ag), gold (Au), and tungsten trioxide (WO3) compared by contact angle images enable Ag and Au prefer to respectively aggregate into isolated islands rather than films at the initial stage of the evaporation process, which was clearly demonstrated in the atomic force microscopy (AFM) measurement. The sum of plasmon-enhanced wavelength range induced by both Ag NPs (350-450 nm) and Au NPs (450-600 nm) almost cover the whole absorption spectra of active layers, which compatibly contribute a significant efficiency improvement from 4.57 ± 0.16 to 6.55 ± 0.12% compared to the one without MNPs. Besides, steady state photoluminescence (PL) measurements provide strong evidence that the SPR induced by the Ag-Au NPs increase the intensity of light absorption. Finally, ultraviolet photoelectron spectroscopy (UPS) reveals that doping Au and Ag causes upper shift of both the work function and valence band of WO3, which is directly related to hole collection ability. We believe the surface-energy-induced dual plasmon resonance enhancement by simple thermally evaporating technique might pave the way toward higher-efficiency PSCs.

  19. Multicolor surface plasmon resonance imaging of ink jet-printed protein microarrays.

    Science.gov (United States)

    Singh, Bipin K; Hillier, Andrew C

    2007-07-15

    We report a technique that utilizes surface plasmon resonance dispersion as a mechanism to provide multicolor contrast for imaging thin molecular films. Illumination of gold surfaces with p-polarized white light in the Kretschmann configuration produces distinct reflected colors due to excitation of surface plasmons and the resulting absorption of specific wavelengths from the source light. In addition, these colors transform in response to the formation of thin molecular films. This process represents a simple detection method for distinguishing between films of varying thickness in sensor applications. As an example, we interrogated a protein microarray formed by a commercial drop-on-demand chemical ink jet printer. Submonolayer films of a test protein (bovine serum albumin) were readily detected by this method. Analysis of the dispersion relations and absorbance sensitivities illustrate the performance and characteristics of this system. Higher detection sensitivity was achieved at angles where red wavelengths coupled to surface plasmons. However, improved contrast and spatial resolution occurred when the angle of incidence was such that shorter wavelengths coupled to the surface plasmons. Simplified optics combined with the robust microarray printing platform are used to demonstrate the applicability of this technique as a rapid and versatile, high-throughput tool for label-free detection of adsorbed films and macromolecules.

  20. Engineering the magnetic plasmon resonances of metamaterials for high-quality sensing.

    Science.gov (United States)

    Chen, Jing; Fan, Wenfang; Zhang, Tao; Tang, Chaojun; Chen, Xingyu; Wu, Jingjing; Li, Danyang; Yu, Ying

    2017-02-20

    We present a powerful method to enhance the magnetic plasmon (MP) resonances of metamaterials composed of periodic arrays of U-shaped metallic split-ring resonators (SRRs) for high-quality sensing. We show that by suspending the metamaterials to reduce the effect of the substrate, the strong diffraction coupling of MP resonances can be achieved, which leads to a narrow-band mixed MP mode with a large magnetic field enhancement. It is also shown that for such a diffraction coupling, the magnetic field component of the lattice resonance mode of periodic arrays must be parallel to the induced magnetic moment in the metallic SRRs. Importantly, the sensitivity and the figure of merit (FOM) of the suspended metamaterials can reach as high as 1300 nm/RIU and 40, respectively. These results suggest that the proposed metamaterials may find great potential applications in label-free biomedical sensing.

  1. Tunable plasmonic filter with circular metal–insulator– metal ring resonator containing double narrow gaps

    Indian Academy of Sciences (India)

    ZHENG GAIGE; XU LINHUA; LIU YUZHU

    2016-05-01

    Tunable filter based on two metal–insulator–metal (MIM) waveguides coupled to each other by a ring resonator with double narrow gaps is designed and numerically investigated by finitedifference time-domain (FDTD) simulations. The propagating modes of surface plasmon polaritons (SPPs) are studied. By introducing narrow gaps in ring resonators, the transmission in differentresonance modes can be effectively adjusted by changing the gap width (g), and the transmitted peak wavelength has a nonlinear relationship with g. Another structure consisting two cascading ring resonators and regular MIM waveguide have also been proposed. The mechanism based on circular ring resonators with narrow gaps may provide a novel method for designing all-opticalintegrated components in optical communication and computing.

  2. Plasmonic properties of gold nanoparticles can promote neuronal activity

    Science.gov (United States)

    Paviolo, Chiara; Haycock, John W.; Yong, Jiawey; Yu, Aimin; McArthur, Sally L.; Stoddart, Paul R.

    2013-02-01

    As-synthesized, poly(4-styrenesulfonic acid) (PSS)-coated and SiO2 coated gold nanorods were taken up by NG108-15 neuronal cells. Exposure to laser light at the plasmon resonance wavelength of gold nanorods was found to trigger the differentiation process in the nanoparticle treated cells. Results were assessed by measuring the maximum neurite length, the number of neurites per neuron and the percentage of neurons with neurites. When the intracellular Ca2+ signaling was monitored, evidence of photo-generated transients were recorded without altering other normal cell functions. These results open new opportunities for peripheral nerve regeneration treatments and for the process of infrared nerve stimulation.

  3. Angular characteristics of a multimode fiber surface plasmon resonance sensor

    CERN Document Server

    Tan, Zhixin; Li, Xuejin; Chen, Yuzhi; Hong, Xueming; Fan, Ping

    2015-01-01

    In this paper the angular characteristics of a multimode fiber SPR sensor are investigated theoretically. By separating the contributions of beams incident at different angles, a compact model is presented to predict the shift of the resonance wavelength with respect to the angle and the environmental refractive index. The result suggests that the performance of conventional fiber SPR sensors can be substantially improved by optimizing the incident angle.

  4. Observation of optical domino modes in arrays of non-resonant plasmonic nanoantennas

    Science.gov (United States)

    Sinev, Ivan S.; Samusev, Anton K.; Voroshilov, Pavel M.; Mukhin, Ivan S.; Denisyuk, Andrey I.; Guzhva, Mikhail E.; Belov, Pavel A.; Simovski, Constantin R.

    2014-09-01

    Domino modes are highly-confined collectivemodes that were first predicted for a periodic arrangement of metallic parallelepipeds in far-infrared region. The main feature of domino modes is the advantageous distribution of the local electric field, which is concentrated between metallic elements (hot spots), while its penetration depth in metal is much smaller than the skin-depth. Therefore, arrays of non-resonant plasmonic nanoantennas exhibiting domino modes can be employed as broadband light trapping coatings for thin-film solar cells. However, until now in the excitation of such modes was demonstrated only in numerical simulations. Here, we for the first time demonstrate experimentally the excitation of optical domino modes in arrays of non-resonant plasmonic nanoantennas. We characterize the nanoantenna arrays produced by means of electron beam lithography both experimentally using an aperture-type near-field scanning optical microscope and numerically. The proof of domino modes concept for plasmonic arrays of nanoantennas in the visible spectral region opens new pathways for development of low-absorptive structures for effective focusing of light at the nanoscale.

  5. Resonant tunneling assisted propagation and amplification of plasmons in high electron mobility transistors

    Energy Technology Data Exchange (ETDEWEB)

    Bhardwaj, Shubhendu [Electrical and Computer Engineering Department, The Ohio State University, Columbus, OH 43212 (United States); Sensale-Rodriguez, Berardi [Electrical and Computer Engineering Department, The University of Utah, Salt Lake City, UT 84112 (United States); Xing, Huili Grace [School of Electrical and Computer Engineering and Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853 (United States); Department of Electrical Engineering, University of Notre Dame, IN 46556 (United States); Rajan, Siddharth [Electrical and Computer Engineering Department and Materials Science Engineering Department, The Ohio State University, Columbus, OH 43212 (United States); Volakis, John L.

    2016-01-07

    A rigorous theoretical and computational model is developed for the plasma-wave propagation in high electron mobility transistor structures with electron injection from a resonant tunneling diode at the gate. We discuss the conditions in which low-loss and sustainable plasmon modes can be supported in such structures. The developed analytical model is used to derive the dispersion relation for these plasmon-modes. A non-linear full-wave-hydrodynamic numerical solver is also developed using a finite difference time domain algorithm. The developed analytical solutions are validated via the numerical solution. We also verify previous observations that were based on a simplified transmission line model. It is shown that at high levels of negative differential conductance, plasmon amplification is indeed possible. The proposed rigorous models can enable accurate design and optimization of practical resonant tunnel diode-based plasma-wave devices for terahertz sources, mixers, and detectors, by allowing a precise representation of their coupling when integrated with other electromagnetic structures.

  6. Synthesis of gold nanorods with a longitudinal surface plasmon resonance peak of around 1250 nm

    Science.gov (United States)

    Nguyen, Thi Nhat Hang; Le Trinh Nguyen, Thi; Thanh Tuyen Luong, Thi; Thang Nguyen, Canh Minh; Nguyen, Thi Phuong Phong

    2016-03-01

    We prepared gold nanorods and joined them to chemicals such as tetrachloauric (III) acid trihydrate, silver nitrate, hydroquinone, hexadecyltrimethylammonium bromide, sodium hydroxide and sodium borohydride using the seed-mediated method. The combination of hydroquinone, with or without salicylic acid, influences the size of the gold nanorods, and this is demonstrated by the results of TEM images, UV-vis spectra and the value of the longitudinal surface plasmon resonance peak with respect to the UV-vis spectra. By changing the Ag+ ion and hydroquinone concentration and the combination of hydroquinone and salicylic acid, the size of the gold nanorods can be controlled and this is manifested by longitudinal surface plasmon resonance peaks forming between 875 and 1278 nm. In particular, sample E2 achieved a longitudinal surface plasmon peak at 1273 nm and an aspect ratio of more than 10 by modifying the hydroquinone to 2.5 mM and salicylic acid to 0.5 mM concentration in the growth solution.

  7. Plasmon-coupled resonance energy transfer: A real-time electrodynamics approach.

    Science.gov (United States)

    Ding, Wendu; Hsu, Liang-Yan; Schatz, George C

    2017-02-14

    This paper presents a new real-time electrodynamics approach for determining the rate of resonance energy transfer (RET) between two molecules in the presence of plasmonic or other nanostructures (inhomogeneous absorbing and dispersive media). In this approach to plasmon-coupled resonance energy transfer (PC-RET), we develop a classical electrodynamics expression for the energy transfer matrix element which is evaluated using the finite-difference time-domain (FDTD) method to solve Maxwell's equations for the electric field generated by the molecular donor and evaluated at the position of the molecular acceptor. We demonstrate that this approach yields RET rates in homogeneous media that are in precise agreement with analytical theory based on quantum electrodynamics (QED). In the presence of gold nanoparticles, our theory shows that the long-range decay of the RET rates can be significantly modified by plasmon excitation, with rates increased by as much as a factor of 10(6) leading to energy transfer rates over hundreds of nm that are comparable to that over tens of nm in the absence of the nanoparticles. These promising results suggest important future applications of the PC-RET in areas involving light harvesting or sensing, where energy transfer processes involving inhomogeneous absorbing and dispersive media are commonplace.

  8. Chiral and Achiral Nanodumbbell Dimers: The Effect of Geometry on Plasmonic Properties.

    Science.gov (United States)

    Smith, Kyle W; Zhao, Hangqi; Zhang, Hui; Sánchez-Iglesias, Ana; Grzelczak, Marek; Wang, Yumin; Chang, Wei-Shun; Nordlander, Peter; Liz-Marzán, Luis M; Link, Stephan

    2016-06-28

    Metal nanoparticles with a dumbbell-like geometry have plasmonic properties similar to those of their nanorod counterparts, but the unique steric constraints induced by their enlarged tips result in distinct geometries when self-assembled. Here, we investigate gold dumbbells that are assembled into dimers within polymeric micelles. A single-particle approach with correlated scanning electron microscopy and dark-field scattering spectroscopy reveals the effects of dimer geometry variation on the scattering properties. The dimers are prepared using exclusively achiral reagents, and the resulting dimer solution produces no detectable ensemble circular dichroism response. However, single-particle circular differential scattering measurements uncover that this dimer sample is a racemic mixture of individual nanostructures with significant positive and negative chiroptical signals. These measurements are complemented with detailed simulations that confirm the influence of various symmetry elements on the overall peak resonance energy, spectral line shape, and circular differential scattering response. This work expands the current understanding of the influence self-assembled geometries have on plasmonic properties, particularly with regard to chiral and/or racemic samples which may have significant optical activity that may be overlooked when using exclusively ensemble characterization techniques.

  9. Plasmonically Enhanced Photocatalytic Hydrogen Production from Water: The Critical Role of Tunable Surface Plasmon Resonance from Gold-Silver Nanoshells.

    Science.gov (United States)

    Li, Chien-Hung; Li, Min-Chih; Liu, Si-Ping; Jamison, Andrew C; Lee, Dahye; Lee, T Randall; Lee, Tai-Chou

    2016-04-13

    Gold-silver nanoshells (GS-NSs) having a tunable surface plasmon resonance (SPR) were employed to facilitate charge separation of photoexcited carriers in the photocalytic production of hydrogen from water. Zinc indium sulfide (ZnIn2S4; ZIS), a visible-light-active photocatalyst, where the band gap varies with the [Zn]/[In] ratio, was used as a model ZIS system (E(g) = 2.25 eV) to investigate the mechanisms of plasmonic enhancement associated with the nanoshells. Three types of GS-NS cores with intense absorptions centered roughly at 500, 700, and 900 nm were used as seeds for preparing GS-NS@ZIS core-shell structures via a microwave-assisted hydrothermal reaction, yielding core-shell particles with composite diameters of ∼200 nm. Notably, an interlayer of dielectric silica (SiO2) between the GS-NSs and the ZIS photocatalyst provided another parameter to enhance the production of hydrogen and to distinguish the charge-transfer mechanisms. In particular, the direct transfer of hot electrons from the GS-NSs to the ZIS photocatalyst was blocked by this layer. Of the 10 particle samples examined in this study, the greatest hydrogen gas evolution rate was observed for GS-NSs having a SiO2 interlayer thickness of ∼17 nm and an SPR absorption centered at ∼700 nm, yielding a rate 2.6 times higher than that of the ZIS without GS-NSs. The apparent quantum efficiencies for these core-shell particles were recorded and compared to the absorption spectra. Analyses of the charge-transfer mechanisms were evaluated and are discussed based on the experimental findings.

  10. Investigation of surface plasmon resonance in composite nanostructure of silver film and nanowire array

    Science.gov (United States)

    Li, Jun; Yang, Junyi; Wu, Xingzhi; Song, Yinglin

    2016-10-01

    We investigate the surface plasmon resonance in a new composite nanostructure (Nanowires array beneath metal film). Computational simulation results exhibit that, for both transverse electric(TE) and transverse magnetic (TM) polarization, the positions of resonance peaks is extremely sensitive to the change of center distance (Filling ratio of nanowires). When the diameter of Nanowires is 4nm and under TM polarization, the resonance angle increasing with the increase of center distance. In the case of TE polarization, the result is completely the opposite within limits. It is also shown that changes in thickness of Ag film(At the top of the Ag nanowire) has little direct effect on the resonance angle, But the characteritics of SPR intensity is influenced by the thickness of Ag film in the most degree. When the thickness of Ag film is 50 nm, In range of 10nm to 100nm, the minimum value of the reflectance is only 0.05, the result is consistent with the previous studies. Additionally, the nano composite structure material is very sensitive to the refractive index change of the lowest layer when under the TE- polarization. we have done mode analysis of the SPR structure for both simple and practical structures using comsol multiphysics, our approach is intend to show the feasibity and extend the applicability of the plasmonic nanowires, could lead to provide the basis for design the new structure of nanowires array.

  11. Plasmon resonance optical tuning based on photosensitive composite structures

    DEFF Research Database (Denmark)

    Gilardi, Giovanni; Xiao, Sanshui; Mortensen, N. Asger

    2014-01-01

    This paper reports a numerical investigation of a periodic metallic structure sandwiched between two quartz plates. The volume comprised between the quartz plates and the metallic structure is infiltrated by a mixture of azo-dye-doped liquid crystal. The exposure to a low power visible light beam...... modifies the azo dye molecular configuration, thus allowing the wavelength shift of the resonance of the system. The wavelength shift depends on the geometry of the periodic structure and it also depends on the intensity of the visible light beam....

  12. Passive Infrared Sensing Using Plasmonic Resonant Dust Particles

    Science.gov (United States)

    2012-01-01

    1 R efl ec ta n ce 8 9 10 11 12 13 14 Incidence wavelength (μm) Polarization parallel to gold strips Polarization perpendicular to gold strips...since the orientation of 4 International Journal of Optics 0 0.5 1 1.5 R efl ec ta n ce 8 9 10 11 12 13 14 Incidence wavelength (μm) Normally incident...strong. The bandwidth of the resonance also remains relatively fixed as the substrate thicknesses is varied. 0 0.5 1 1.5 R efl ec ta n ce 8 9 10 11 12 13

  13. Development of a fiber optic sensor based on gold island plasmon resonance

    Science.gov (United States)

    Meriaudeau, Fabrice; Downey, Todd R.; Passian, A.; Wig, A. G.; Mangeant, S.; Crilly, P. B.; Ferrell, Trinidad L.

    1998-12-01

    We present an optical fiber chemical sensor based on gold- island surface plasmon excitation. The sensing part of the fiber is a one inch portion on which cladding has been removed and onto which a thin layer of gold (40 angstroms) has been deposited to form a particulate surface. Annealing the gold reshapes the particles and produces an absorbance near 535 nm when the only medium residing outside the surface is air. A range of wavelengths provided by a white light source and monochromator is launched through the optical fiber. The transmitted spectra display shifts in the resonance absorption due to any changes in the medium surrounding, or adsorbed onto the fiber. Experimental results for the sensitivity and dynamic range in the measurement of liquid solutions are in agreement with a basic theoretical model which characterizes the surface plasmon using nonretarded electrodynamics. Furthermore, the model assumes the particles are isolated oblate spheroids with a distribution of eccentricities.

  14. Hafnium dioxide as a dielectric for highly-sensitive waveguide-coupled surface plasmon resonance sensors

    Directory of Open Access Journals (Sweden)

    Kunal Tiwari

    2016-04-01

    Full Text Available Hafnium dioxide has been recognized as an excellent dielectric for microelectronics. However, its usefulness for the surface plasmon based sensors has not yet been tested. Here we investigate its usefulness for waveguide-coupled bi-metallic surface plasmon resonance sensors. Several Ag/HfO2/Au multilayer structure sensors were fabricated and evaluated by optical measurements and computer simulations. The resulting data establish correlations between the growth parameters and sensor performance. The sensor sensitivity to refractive index of analytes is determined to be S n = ∂ θ SPR ∂ n ≥ 4 7 0 . The sensitivity data are supported by simulations, which also predict 314 nm for the evanescent field decay length in air.

  15. Electron Photoemission in Plasmonic Nanoparticle Arrays: Analysis of Collective Resonances and Embedding Effects

    CERN Document Server

    Zhukovsky, Sergei V; Uskov, Alexander V; Protsenko, Igor E; Lavrinenko, Andrei V

    2013-01-01

    We theoretically study the characteristics of photoelectron emission in plasmonic nanoparticle arrays. Nanoparticles are partially embedded in a semiconductor, forming Schottky barriers at metal/semiconductor interfaces through which photoelectrons can tunnel from the nanoparticle into the semiconductor; photodetection in the infrared range, where photon energies are below the semiconductor band gap (insufficient for band-to-band absorption in semiconductor), is therefore possible. The nanoparticles are arranged in a sparse rectangular lattice so that the wavelength of the lattice-induced Rayleigh anomalies can overlap the wavelength of the localized surface plasmon resonance of the individual particles, bringing about collective effects from the nanoparticle array. Using full-wave numerical simulations, we analyze the effects of lattice constant, embedding depth, and refractive index step between the semiconductor layer and an adjacent transparent conductive oxide layer. We show that the presence of refracti...

  16. A saccharides sensor developed by symmetrical optical waveguide-based surface plasmon resonance

    Directory of Open Access Journals (Sweden)

    Ang Li

    2015-03-01

    Full Text Available We proposed a new saccharides sensor developed by symmetrical optical waveguide (SOW-based surface plasmon resonance (SPR. This unique MgF2/Au/MgF2/Analyte film structure results in longer surface plasmon wave (SPW propagation lengths and depths, leading to an increment of resolution. In this paper, we managed to decorate the dielectric interface (MgF2 layer by depositing a thin polydopamine film as surface-adherent that provides a platform for secondary reactions with the probe molecule. 3-Aminophenylboronic acid (3-PBA is chosen to be the saccharides sense probe molecule in the present work. The aqueous humor of Diabetes and Cataract patient whose blood glucose level is normal are analyzed and the results demonstrated that this sensor shows great potential in monitoring the blood sugar and can be adapted in the field of biological monitoring in the future.

  17. Surface plasmon resonance sensors a materials guide to design and optimization

    CERN Document Server

    Oliveira, Leiva Casemiro; Thirstrup, Carsten; Neff, Helmut Franz

    2015-01-01

    This book addresses the important physical phenomenon of Surface Plasmon Resonance or Surface Plasmon Polaritons in thin metal films, a phenomenon which is exploited in the design of a large variety of physico-chemical optical sensors. In this treatment, crucial materials aspects for design and optimization of SPR sensors are investigated and outlined in detail. The text covers the selection of nanometer thin metal films, ranging from free-electron to the platinum type conductors, along with their combination with a large variety of dielectric substrate materials, and associated individual layer and opto-geometric arrangements. Furthermore, as-yet hardly explored SPR features of selected metal–metal and metal–dielectric super lattices are included in this report. An in-depth multilayer Fresnel evaluation provides the mathematical tool for this optical analysis, which otherwise relies solely on experimentally determined electro-optical materials parameters.

  18. New trends in instrumental design for surface plasmon resonance-based biosensors.

    Science.gov (United States)

    Abbas, Abdennour; Linman, Matthew J; Cheng, Quan

    2011-01-15

    Surface plasmon resonance (SPR)-based biosensing is one of the most advanced label free, real time detection technologies. Numerous research groups with divergent scientific backgrounds have investigated the application of SPR biosensors and studied the fundamental aspects of surface plasmon polaritons that led to new, related instrumentation. As a result, this field continues to be at the forefront of evolving sensing technology. This review emphasizes the new developments in the field of SPR-related instrumentation including optical platforms, chips design, nanoscale approach and new materials. The current tendencies in SPR-based biosensing are identified and the future direction of SPR biosensor technology is broadly discussed. Copyright © 2010 Elsevier B.V. All rights reserved.

  19. Guiding light by plasmonic resonant solitons in metallic nanosuspensions (Presentation Recording)

    Science.gov (United States)

    Kelly, Trevor S.; Samadi, Akbar; Bezryadina, Anna; Chen, Zhigang

    2015-09-01

    In typical colloidal suspensions, the corresponding optical polarizability is positive, and thus enhanced scattering takes place as optical beams tend to catastrophically collapse during propagation. Recently, light penetration deep inside scattering suspensions has been realized by engineering dielectric or plasmonic nanoparticle polarizibilities. In particular, we have previously demonstrated two types of soft-matter systems with tunable optical nonlinearities - the dielectric and metallic colloidal suspensions, in which the effects of diffraction and scattering were overcome, hence achieving deep penetration of a light needle through the suspension. In this work, we show that waveguides can be established in soft matter systems such as metallic nanosuspensions through the formation of plasmonic resonant solitons. First, we show that, due to plasmonic resonance, a 1064nm laser beam (probe) would not experience appreciable nonlinear self-action while propagating through 4cm cuvette containing the metallic nanosuspension of gold spheres (40nm), whereas a 532nm laser beam (pump) can readily form a spatial soliton due to nonlinear self-trapping. Second, we demonstrate effective guidance of the probe beam, which would otherwise diffract significantly through the nanosuspensions, due to the soliton-induced waveguide from the pump beam. Such guidance was observed when the power of the probe beam was varied from 20mW to 500mW at constant pump beam power, with more pronounced guidance realized from lower to higher probe beam power. Interestingly, due to the presence of the probe beam, the pump beam undergoes self-trapping at an even lower power. These results may bring about the possibility of engineering plasmonic soliton-based waveguides for many applications.

  20. pH tunability and influence of alkali metal basicity on the plasmonic resonance of silver nanoparticles

    Science.gov (United States)

    Yadav, Vijay D.; Akhil Krishnan, R.; Borade, Lalit; Shirolikar, Seema; Jain, Ratnesh; Dandekar, Prajakta

    2017-07-01

    Localized surface plasmon resonance has been a unique and intriguing feature of silver nanoparticles (AgNPs) that has attracted immense attention. This has led to an array of applications for AgNPs in optics, sensors, plasmonic imaging etc. Although numerous applications have been reported consistently, the importance of buffer and reaction parameters during the synthesis of AgNPs, is still unclear. In the present study, we have demonstrated the influence of parameters like pH, temperature and buffer conditions (0.1 M citrate buffer) on the plasmonic resonance of AgNPs. We found that neutral and basic pH (from alkali metal) provide optimum interaction conditions for nucleation of plasmon resonant AgNPs. Interestingly, this was not observed in the non-alkali metal base (ammonia). Also, when the nanoparticles synthesized from alkali metal base were incorporated in different buffers, it was observed that the nanoparticles dissolved in the acidic buffer and had reduced plasmonic resonance intensity. This, however, was resolved in the basic buffer, increasing the plasmonic resonance intensity and confirming that nucleation of nanoparticles required basic conditions. The above inference has been supported by characterization of AgNPs using UV-Vis spectrophotometer, Fluorimetry analysis, Infrared spectrometer and TEM analysis. The study concluded that the plasmonic resonance of AgNPs occurs due to the interaction of alkali (Na) and transition metal (Ag) salt in basic/neutral conditions, at a specific temperature range, in presence of a capping agent (citric acid), providing a pH tune to the overall system.