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Sample records for plasmon resonance lspr

  1. Signal Amplification by Enzymatic Reaction in an Immunosensor Based on Localized Surface Plasmon Resonance (LSPR

    Directory of Open Access Journals (Sweden)

    Yong-Beom Shin

    2010-03-01

    Full Text Available An enzymatic reaction was employed as a means to enhance the sensitivity of an immunosensor based on localized surface plasmon resonance (LSPR. The reaction occurs after intermolecular binding between an antigen and an antibody on gold nano-island (NI surfaces. For LSPR sensing, the gold NI surface was fabricated on glass substrates using vacuum evaporation and heat treatment. The interferon-g (IFN-g capture antibody was immobilized on the gold NIs, followed by binding of IFN-g to the antibody. Subsequently, a biotinylated antibody and a horseradish peroxidase (HRP conjugated with avidin were simultaneously introduced. A solution of 4-chloro-1-naphthol (4-CN was then used for precipitation; precipitation was the result of the enzymatic reaction catalyzed the HRP on gold NIs. The LSPR spectra were obtained after each binding process. Using this method, the enzyme-catalyzed precipitation reaction on the gold NI surface was found to effectively amplify the change in the signal of the LSPR immunosensor after intermolecular binding.

  2. Detection of Biomolecular Binding Through Enhancement of Localized Surface Plasmon Resonance (LSPR by Gold Nanoparticles

    Directory of Open Access Journals (Sweden)

    Min-Gon Kim

    2009-03-01

    Full Text Available To amplify the difference in localized surface plasmon resonance (LSPR spectra of gold nano-islands due to intermolecular binding events, gold nanoparticles were used. LSPR-based optical biosensors consisting of gold nano-islands were readily made on glass substrates using evaporation and heat treatment. Streptavidin (STA and biotinylated bovine serum albumin (Bio-BSA were chosen as the model receptor and the model analyte, respectively, to demonstrate the effectiveness of this detection method. Using this model system, we were able to enhance the sensitivity in monitoring the binding of Bio-BSA to gold nano-island surfaces functionalized with STA through the addition of gold nanoparticle-STA conjugates. In addition, SU-8 well chips with gold nano-island surfaces were fabricated through a conventional UV patterning method and were then utilized for image detection using the attenuated total reflection mode. These results suggest that the gold nano-island well chip may have the potential to be used for multiple and simultaneous detection of various bio-substances.

  3. 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.

  4. An investigation of localised surface plasmon resonance (LSPR) of Ag nanoparticles produced by pulsed laser deposition (PLD) technique

    Science.gov (United States)

    Gezgin, Serap Yiǧit; Kepceoǧlu, Abdullah; Kılıç, Hamdi Şükür

    2017-02-01

    Noble metal nano-structures such as Ag, Cu, Au are used commonly to increase power conversion efficiency of the solar cell by using their surface plasmons. The plasmonic metal nanoparticles of Ag among others that have strong LSPR in near UV range. They increase photon absorbance via embedding in the active semiconductor of the solar cell. Thin films of Ag are grown in the desired particle size and interparticle distance easily and at low cost by PLD technique. Ag nanoparticle thin films were grown on micro slide glass at 25-36 mJ laser pulse energies under by PLD using ns-Nd:YAG laser. The result of this work have been presented by carrying out UV-VIS and AFM analysis. It was concluded that a laser energy increases, the density and size of Ag-NPs arriving on the substrate increases, and the interparticle distance was decreases. Therefore, LSPR wavelength shifts towards to longer wavelength region.

  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. 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.

  7. 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.

  8. Enhanced sensitivity of localized surface plasmon resonance biosensor by phase interrogation

    Science.gov (United States)

    Li, Chung-Tien; Chen, How-foo; Yen, Ta-Jen

    2011-05-01

    We proposed an innovative phase interrogation method for localized surface plasmon resonance (LSPR) detection. To our knowledge, this is the first demonstration of LSPR biosensor by phase interrogation. LSPR is realized as the plasmonic resonance within confined metal nanoparticle. Nanoparticle couples the light by means of a non-radiative inter-band absorption, and a scattering from surface plasmon oscillation, the total contribution is the optical extinction of nanoparticles. Due to the variety of resonance types, LSPR is extensively studied in the field of biological sensing, imaging, and medical therapeutics. Generally, LSPR is probed by optical intensity variation of continuous wavelength, in other words, wavelength interrogation. LSPR sensitivity probed by this method is ranged from several tens nm/RIU to less than 1000nm/RIU depending on the nanostructure and metal species, which at least an order of magnitude less than conventional SPR biosensor in wavelength interrogation. In this work, an innovative common-path phase interrogation system is applied for LSPR detection. Phase difference in our home-made system is simply extracted through the correlation of optical intensity under different polarization without any heterodyne optical modulator or piezoelectric transducer, and thus low down the cost and complexity in optical setup. In addition, signal-to-noise ratio is substantially reduced since the signal wave and reference wave share the common path. In our preliminary results, LSPR resolution of Au nanodisk array is 1.74 x 10-4 RIU by wavelength interrogation; on the other side, LSPR resolution of Au nanodisk array is 2.02x10-6 RIU in phase interrogation. LSPR sensitivity is around one order of magnitude enhanced. In conclusion, we demonstrated that LSPR sensitivity can be further enhanced by phase interrogation.

  9. Localized surface plasmon resonance biosensing with large area of gold nanoholes fabricated by nanosphere lithography.

    Science.gov (United States)

    Xiang, Gansheng; Zhang, Nan; Zhou, Xiaodong

    2010-03-09

    Localized surface plasmon resonance (LSPR) has been extensively studied as potential chemical and biological sensing platform due to its high sensitivity to local refractive index change induced by molecule adsorbate. Previous experiments have demonstrated the LSPR generated by gold nanoholes and its biosensing. Here, we realize large uniform area of nanoholes on scale of cm2 on glass substrate by nanosphere lithography which is essential for mass production. The morphology of the nanoholes is characterized using scanning electron microscope and atomic force microscope. The LSPR sensitivity of the nanoholes to local refractive index is measured to be 36 nm/RIU. However, the chip has demonstrated high sensitivity and specificity in biosensing: bovine serum albumin adsorption is detected with LSPR peak redshift of 27 nm, and biotin-streptavidin immunoassay renders a LSPR redshift of 11 nm. This work forms a foundation toward the cost-effective, high-throughput, reliable and robust chip-based LSPR biosensor.

  10. Localized Surface Plasmon Resonance Biosensing with Large Area of Gold Nanoholes Fabricated by Nanosphere Lithography

    Directory of Open Access Journals (Sweden)

    Zhang Nan

    2010-01-01

    Full Text Available Abstract Localized surface plasmon resonance (LSPR has been extensively studied as potential chemical and biological sensing platform due to its high sensitivity to local refractive index change induced by molecule adsorbate. Previous experiments have demonstrated the LSPR generated by gold nanoholes and its biosensing. Here, we realize large uniform area of nanoholes on scale of cm2 on glass substrate by nanosphere lithography which is essential for mass production. The morphology of the nanoholes is characterized using scanning electron microscope and atomic force microscope. The LSPR sensitivity of the nanoholes to local refractive index is measured to be 36 nm/RIU. However, the chip has demonstrated high sensitivity and specificity in biosensing: bovine serum albumin adsorption is detected with LSPR peak redshift of 27 nm, and biotin-streptavidin immunoassay renders a LSPR redshift of 11 nm. This work forms a foundation toward the cost-effective, high-throughput, reliable and robust chip-based LSPR biosensor.

  11. 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

  12. 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.

  13. 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.)

  14. Lithography-Free Fabrication of Silica Nanocylinders with Suspended Gold Nanorings for LSPR-Based Sensing

    DEFF Research Database (Denmark)

    Thilsted, Anil Haraksingh; Pan, Jesper Yue; Wu, Kaiyu;

    2016-01-01

    areas, such as 8 in. wafers. The authors demonstrate that gold coated nanocylinders support localized surface plasmon resonances (LSPR) from visible to near infrared wavelengths. The plasmonic platform can be characterized as suspended gold nanorings and exhibits a sensitivity of 658 nm RIU-1...... with a figure-of-merit of 10, comparable to other state-of-the-art LSPR sensing platforms that utilize more complex nanofabrication pathways. It was observed that the LSPR peak positions can be controlled by varying the geometry of the nanocylinders. The authors illustrate surface functionalization, biosensing...

  15. 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.

  16. 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...

  17. 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...

  18. Effective approach to strengthen plasmon resonance localized on top surfaces of Ag nanoparticles and application in surface-enhanced Raman spectroscopy

    Science.gov (United States)

    Zhan, Zhibing; Xu, Rui; Zheng, Xianzheng; Fu, Qun; Wu, Minghong; Lei, Yong

    2016-11-01

    The spatial distribution of localized surface plasmon resonance (LSPR) plays a key role in many plasmonic applications. Based on the thermal stability of alumina templates, this work reports a novel approach to manipulate the distribution of LSPR and exhibits its significance for an important plasmonic application, the surface-enhanced Raman spectroscopy (SERS). A suitable thermal annealing sharpens the edges in top surfaces (far from the substrates) of Ag nanoparticles, which significantly strengthens the distal mode (DM) with the LSPR excited on the top surfaces. Because the top surface is the major place to adsorb probe molecules, this manipulation greatly improves the detection sensitivity of SERS. Our research provides a new way to improve the sensitivity of SERS, which also indicates that great care has to be taken on special LSPR mode which is largely responsible for a certain plasmonic application (e.g., the DM for SERS although it is not the major mode).

  19. 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.

  20. Fabrication Localized Surface Plasmon Resonance sensor chip of gold nanoparticles and detection lipase–osmolytes interaction

    Energy Technology Data Exchange (ETDEWEB)

    Ghodselahi, T., E-mail: t_ghodselahi@yahoo.com [Nano Mabna Iranian Inc., PO Box 1676664116, Tehran (Iran, Islamic Republic of); School of Physics, Institute for Research in Fundamental Sciences, PO Box 19395-5531, Tehran (Iran, Islamic Republic of); Hoornam, S. [Nano Mabna Iranian Inc., PO Box 1676664116, Tehran (Iran, Islamic Republic of); School of Physics, Institute for Research in Fundamental Sciences, PO Box 19395-5531, Tehran (Iran, Islamic Republic of); Department of Science, Central Tehran Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Vesaghi, M.A. [Department of Physics, Sharif University of Technology, PO Box 11365-9161, Tehran (Iran, Islamic Republic of); Ranjbar, B.; Azizi, A. [Department of Biophysics, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Mobasheri, H. [Laboratory of Membrane Biophysics, Institute of Biochemistry and Biophysics, University of Tehran, PO Box 13145-1384, Tehran (Iran, Islamic Republic of); Biomaterials Research Institute (BRC), University of Tehran, Tehran (Iran, Islamic Republic of)

    2014-09-30

    Highlights: • We synthesized localized surface plasmon resonance sensor of gold nanoparticles by RF-sputtering and RF-PECVD. • LSPR sensor was characterized by TEM, XPS, AFM. • LSPR sensor was utilized to detect interaction between sorbitol and trehalose, with Pesudomonace Cepacia Lipase (PCL). • Unlike to trehalose, sorbitol interacts with the PCL. • Refractive index of PCL was obtained by Mie theory modeling. - Abstract: Co-deposition of RF-sputtering and RF-PECVD from acetylene gas and Au target were used to prepare sensor chip of gold nanoparticles (Au NPs). Deposition conditions were optimized to reach a Localized Surface Plasmon Resonance (LSPR) sensor chip of Au NPs with particle size less than 10 nm. The RF power was set at 180 W and the initial gas pressure was set at 0.035 mbar. Transmission Electron Microscopy (TEM) images and Atomic Force Microscopy (AFM) data were used to investigate particles size and surface morphology of LSPR sensor chip. The Au and C content of the LSPR sensor chip of Au NPs was obtained from X-ray photoelectron spectroscopy (XPS). The hydrogenated amorphous carbon (a-C:H) thin film was used as intermediate material to immobilize Au NPs on the SiO{sub 2} substrate. The interaction between two types of osmolytes, i.e. sorbitol and trehalose, with Pseudomonas cepacia lipase (PCL) were detected by the prepared LSPR biosensor chip. The detection mechanism is based on LSPR spectroscopy in which the wavelength of absorption peak is sensitive to the refractive index of the environment of the Au NPs. This mechanism eliminates the use of a probe or immobilization of PCL on the Au NPs of LSPR sensor chip. The interaction between PCL and osmolytes can change refractive index of the mixture or solution. We found that unlike to trehalose, sorbitol interacts with the PCL. This interaction increases refractive index of the PCL and sorbitol mixture. Refractive index of PCL in the presence of different concentration of sorbitol was

  1. Towards a high-throughput label-free detection system combining localized-surface plasmon resonance and microfluidics.

    Science.gov (United States)

    Zhang, Yi; Tang, Yunfang; Hsieh, Yi-Heui; Hsu, Chuen-Yuan; Xi, Jianzhong; Lin, Kuan-Jiuh; Jiang, Xingyu

    2012-09-07

    This work reports an integrated platform combining localized-surface plasmon resonance (LSPR) and microfluidic chips to carry out multiplexed and label-free protein analysis. We fabricated an optical bench to enable detection using only a laboratory UV-Vis spectrophotometer. This assay not only improves throughput, but also allows quantitative analysis.

  2. 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.

  3. 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.

  4. 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.

  5. Fabrication LSPR sensor chip of Ag NPs and their biosensor application based on interparticle coupling

    Energy Technology Data Exchange (ETDEWEB)

    Ghodselahi, T., E-mail: t_ghodselahi@yahoo.com [Nano Mabna Iranian Inc., PO Box 1676664116, Tehran (Iran, Islamic Republic of); School of Physics, Institute for Research in Fundamental Sciences, PO Box 19395-5531, Tehran (Iran, Islamic Republic of); Neishaboorynejad, T. [School of Physics, Institute for Research in Fundamental Sciences, PO Box 19395-5531, Tehran (Iran, Islamic Republic of); Department of Physics, Central Tehran Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Arsalani, S. [School of Physics, Institute for Research in Fundamental Sciences, PO Box 19395-5531, Tehran (Iran, Islamic Republic of); School of Medicine, Bam University of Medical Sciences, Bam (Iran, Islamic Republic of)

    2015-07-15

    Highlights: • Localized surface plasmon resonance (LSPR) sensor of silver nanoparticles on hydrogenated amorphous carbon thin film were synthetized by co-deposition of RF-sputtering and RF-PECVD. • Samples were characterized by XRD, XPS, AFM, and UV visible. • DNA primer at fM concentration was detected based on breaking of inter-particles coupling. • Dipolar plasmon of isolated Ag NPs, coupled Ag NPs plasmons, in-plane and out-plane coupling, and quadrupole plasmon modes were considered to explain biosensor properties. • The initial response, wavelength shift sensitivity, and response time of LSPR sensors were compared by morphology. - Abstract: We introduce a simple method to synthesize localized surface plasmon resonance (LSPR) sensor chip of Ag NPs on the hydrogenated amorphous carbon by co-deposition of RF-Sputtering and RF-PECVD. The X-ray photoelectron spectroscopy revealed the content of Ag and C atoms. X-ray diffraction profile and atomic force microscopy indicate that the Ag NPs have fcc crystal structure and spherical shape and by increasing deposition time, particle sizes do not vary and only Ag NPs aggregation occurs, resulting in LSPR wavelength shift. Firstly, by increasing Ag NPs content, in-plan interparticles coupling is dominant and causes redshift in LSPR. At the early stage of agglomeration, out-plane coupling occurs and in-plane coupling is reduced, resulting a blueshift in the LSPR. By further increasing of Ag NPs content, agglomeration is completed on the substrate and in-plan coupling rises, resulting significant redshift in the LSPR. Results were used to implement biosensor application of chips. Detection of DNA primer at fM concentration was achieved based on breaking interparticles coupling of Ag NPs. A significant wavelength shift sensitivity of 30 nm and a short response time of 30 min were obtained, where both of these are prerequisite for biosensor applications.

  6. 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....

  7. 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.

  8. 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.

  9. Monolayers of gold nanostars with two Near-IR LSPR capable of additive photothermal response

    KAUST Repository

    Pallavicini, Piersandro

    2015-07-06

    Monolayers of photothermally responsive gold nanostars on PEI-coated surfaces display two Localized Surface Plasmon Resonances (LSPR) in the near-IR region that can be laser-irradiated either separately, obtaining two different T jumps, or simultaneously, obtaining a T jump equal to the sum of what obtained with separate irradiations

  10. Feasibility of using LSPR on the biased nanotip to realize the atomic-resolution near-field optical detection

    CERN Document Server

    Lihue, Gong

    2015-01-01

    A near-field optical detection method and its theoretical model are developed, which follow from an algebra-based conclusion: in the localized surface plasmon resonance (LSPR) region, the extinction coefficient of a metal nanosphere is the sesquiplicate proportion of the localized electron density. Eleven spectral tests of gold, silver, and aluminum nanospheres are used to verify this model. For a metal nanosphere, the frequency and intensity of the LSPR are dependent on the localized electron density only. The electron density can be tuned by adjusting the bias voltage, so the bias can enhance or inhibit the LSPR frequency of the metal nanosphere.

  11. Wafer scale imprint uniformity evaluated by LSPR spectroscopy: a high volume characterization method for nanometer scale structures

    DEFF Research Database (Denmark)

    Jeppesen, Claus; Lindstedt, Daniel Nilsson; Vig, Asger Laurberg;

    2012-01-01

    We exploit the localized surface-plasmon resonance (LSPR) of terahertz gold gammadion structures for wafer scale critical dimension metrology of nanostructures. The proposed characterization method, LSPR spectroscopy, is based on optical transmission measurements and is benchmarked against...... numerical simulations of imprinted structures characterized by atomic force microscopy. There is a fair agreement between the two methods and the simulations enable the translation of optical spectra to critical dimensions of the physical structures, a concept known from scatterometry. The results...... demonstrate the potential of LSPR spectroscopy as an alternative characterization method to scanning electron microscopy, atomic force microscopy and scatterometry....

  12. 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...

  13. 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.

  14. Mueller matrix polarimetry of plasmon resonant silver nano-rods: biomedical prospects

    CERN Document Server

    Ghosh, Sayantan; Bera, Sudipta K; Banerjee, Ayan; Ghosh, Nirmalya

    2012-01-01

    Fundamental understanding of the light-matter interaction in the context of nano-particles is immensely bene- fited by the study of geometry dependent tunable Localized Surface Plasmon Resonance (LSPR) and has been demonstrated to have potential applications in various areas of science. The polarization characteristics of LSPR in addition to spectroscopic tuning can be suitably exploited in such systems as contrast enhancement mech- anisms and control parameters. Such polarization characteristics like diattenuation and retardance have been studied here using a novel combination of Muller-matrix polarimetry with the T-matrix matrix approach for silver nano-rods to show unprecedented control and sensitivity to local refractive index variations. The study carried out over various aspect ratios for a constant equal volume sphere radius shows the presence of longitu- dinal (dipolar and quadrupolar) and transverse (dipolar) resonances; arising due to differential contribution of polarizabilities in two directions. ...

  15. 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.

  16. 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.

  17. 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...

  18. Detection of hydrofluoric acid by a SiO2 sol-gel coating fiber-optic probe based on reflection-based localized surface plasmon resonance.

    Science.gov (United States)

    Chen, I-Cherng; Lin, Shiu-Shiung; Lin, Tsao-Jen; Du, Je-Kang

    2011-01-01

    A novel fiber-optic probe based on reflection-based localized surface plasmon resonance (LSPR) was developed to quantify the concentration of hydrofluoric acid (HF) in aqueous solutions. The LSPR sensor was constructed with a gold nanoparticle-modified PMMA fiber, integrated with a SiO(2) sol-gel coating. This fiber-sensor was utilized to assess the relationship between HF concentration and SiO(2) sol-gel layer etching reduction. The results demonstrated the LSPR sensor was capable of detecting HF-related erosion of hydrofluoric acid solutions of concentrations ranging from 1% to 5% using Relative RI Change Rates. The development of the LSPR sensor constitutes the basis of a detector with significant sensitivity for practical use in monitoring HF solution concentrations.

  19. 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.

  20. 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.

  1. Plasmonic metasurfaces for coloration of plastic consumer products.

    Science.gov (United States)

    Clausen, Jeppe S; Højlund-Nielsen, Emil; Christiansen, Alexander B; Yazdi, Sadegh; Grajower, Meir; Taha, Hesham; Levy, Uriel; Kristensen, Anders; Mortensen, N Asger

    2014-08-13

    We present reflective plasmonic colors based on the concept of localized surface plasmon resonances (LSPR) for plastic consumer products. In particular, we bridge the widely existing technological gap between clean-room fabricated plasmonic metasurfaces and the practical call for large-area structurally colored plastic surfaces robust to daily life handling. We utilize the hybridization between LSPR modes in aluminum nanodisks and nanoholes to design and fabricate bright angle-insensitive colors that may be tuned across the entire visible spectrum.

  2. Plasmonic Metasurfaces for Coloration of Plastic Consumer Products

    DEFF Research Database (Denmark)

    Clausen, Jeppe Sandvik; Højlund-Nielsen, Emil; Christiansen, Alexander Bruun;

    2014-01-01

    We present reflective plasmonic colors based on the concept of localized surface plasmon resonances (LSPR) for plastic consumer products. In particular, we bridge the widely existing technological gap between clean-room fabricated plasmonic metasurfaces and the practical call for large......-area structurally colored plastic surfaces robust to daily life handling. We utilize the hybridization between LSPR modes in aluminum nanodisks and nanoholes to design and fabricate bright angle-insensitive colors that may be tuned across the entire visible spectrum....

  3. On the role of localized surface plasmon resonance in UV-Vis light irradiated Au/TiO₂ photocatalysis systems: pros and cons.

    Science.gov (United States)

    Lin, Zhongjin; Wang, Xiaohong; Liu, Jun; Tian, Zunyi; Dai, Loucheng; He, Beibei; Han, Chao; Wu, Yigui; Zeng, Zhigang; Hu, Zhiyu

    2015-03-07

    The role of localized surface plasmon resonance (LSPR) in UV-Vis light irradiated Au/TiO2 photocatalysis systems has been investigated, and it is demonstrated experimentally for the first time that both pros and cons of LSPR exist simultaneously for this photocatalytic reaction. We have proved that when operating under mixed UV and green light irradiation, the LSPR injected hot electrons (from the Au nanoparticles to TiO2 under green light irradiation) may surmount the Schottky barrier (SB) formed between the Au nanoparticles and TiO2, and flow back into the TiO2. As a result, these electrons may compensate for and even surpass those transferred from TiO2 to the Au nanoparticles, thus accelerating the recombination of UV excited electron-hole pairs in TiO2. This is the negative effect of LSPR. On the other hand, more hot electrons existing on the surface of the Au nanoparticles due to LSPR would favor the photocatalytic reaction, which accompanied by the negative effect dominates the overall photocatalytic performance. The presented results reveal the multi-faceted essence of LSPR in Au/TiO2 structures, and is instructive for the application of metal-semiconductor composites in photocatalysis. Moreover, it is confirmed that the extent to which the above pros and cons of LSPR dominate the overall photocatalytic reaction depends on the intensity ratio of visible to UV light.

  4. 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.

  5. 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

  6. PAMAM dendrimer/gold nanoparticle nanocomposites for a reflection LSPR optical fiber sensor

    Science.gov (United States)

    Gouvêa, Paula M. P.; Cancino-Bernardi, Juliana; Zucolotto, Valtencir; Braga, Arthur M. B.; Carvalho, Isabel C. S.

    2015-09-01

    The viability of a fiber optic reflection-based Localized Surface Plasmon Resonance (LSPR) sensor using layer-by-layer technique composed by PAMAM-AuNP with and without AuNP-citrate was investigated. The PAMAM-AuNPs and PAMAM-AuNPs/AuNP-citrate layers were deposited on the endface of an optical fiber and the reflected signal was acquired. Deposition time and number of layers were optimized viewing LSPR sensing applications. Results with and without AuNP-citrate were compared. The sensor is being characterized as a refractive index sensor.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. A saliva molecular imprinted localized surface plasmon resonance biosensor for wine astringency estimation.

    Science.gov (United States)

    Guerreiro, J Rafaela L; Teixeira, Natércia; De Freitas, Victor; Sales, M Goreti F; Sutherland, Duncan S

    2017-10-15

    Wine astringency was evaluated based on the interaction of two complex matrices (red wine and saliva) by combining localized surface plasmon resonance (LSPR) and molecular imprinted polymers (MIP) at gold nanodisks as an alternative to sensorial analysis. The main objective of the work was to simulate wine astringency inside the mouth by mimicking this biological system. The LSPR/MIP sensor provided a linear response for astringency expressed in pentagalloyl glucose (PGG) units in concentrations ranging from 1 to 140μmol/L. The sensor was also applied to wine samples correlating well with sensorial analysis obtained by a trained panel. The correlation of astringency and wine composition was also evaluated showing that anthocyanins may have an important role, not only for pigmentation but also in astringency. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. 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.

  13. 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.

  14. Switching of localized surface plasmon resonance of gold nanoparticles on a GeSbTe film mediated by nanoscale phase change and modification of surface morphology

    Science.gov (United States)

    Hira, T.; Homma, T.; Uchiyama, T.; Kuwamura, K.; Saiki, T.

    2013-12-01

    As a platform for active nanophotonics, localized surface plasmon resonance (LSPR) switching via interaction with a chalcogenide phase change material (GeSbTe) was investigated. We performed single-particle spectroscopy of gold nanoparticles placed on a GeSbTe thin film. By irradiation with a femtosecond pulsed laser for amorphization and a continuous wave laser for crystallization, significant switching behavior of the LSPR band due to the interaction of GeSbTe was observed. The switching mechanism was explained in terms of both a change in the refractive index and a modification of surface morphology accompanying volume expansion and reduction of GeSbTe.

  15. Switching of localized surface plasmon resonance of gold nanoparticles on a GeSbTe film mediated by nanoscale phase change and modification of surface morphology

    Energy Technology Data Exchange (ETDEWEB)

    Hira, T.; Homma, T.; Uchiyama, T.; Kuwamura, K.; Saiki, T. [Graduate School of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku, Yokohama, Kanagawa 223-8522 (Japan)

    2013-12-09

    As a platform for active nanophotonics, localized surface plasmon resonance (LSPR) switching via interaction with a chalcogenide phase change material (GeSbTe) was investigated. We performed single-particle spectroscopy of gold nanoparticles placed on a GeSbTe thin film. By irradiation with a femtosecond pulsed laser for amorphization and a continuous wave laser for crystallization, significant switching behavior of the LSPR band due to the interaction of GeSbTe was observed. The switching mechanism was explained in terms of both a change in the refractive index and a modification of surface morphology accompanying volume expansion and reduction of GeSbTe.

  16. Switching the Localized Surface Plasmon Resonance of Single Gold Nanorods with a Phase-Change Material and the Implementation of a Cellular Automata Algorithm Using a Plasmon Particle Array

    Directory of Open Access Journals (Sweden)

    Takashi Hira

    2015-01-01

    Full Text Available We investigate the modulation of the localized surface plasmon resonance (LSPR of a gold nanorod (AuNR using a GeSbTe film as an active medium. We demonstrate high-contrast switching of LSPR in an AuNR/GST/Au thin film sandwich structure upon phase change. To go beyond this single-particle switching functionality, we consider a plasmon particle system interacting with a phase-change material (PCM to discuss the possibility of parallel processing devices with memory functionality, exploiting the plasticity and threshold behavior that are inherent characteristics of PCMs. We demonstrate that the temporal and spatial evolution of a plasmon-PCM array system can be equivalent to a cellular automata algorithm.

  17. 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.

  18. Fabrication of Gold Nanodot Array for the Localized Surface Plasmon Resonance

    Directory of Open Access Journals (Sweden)

    Young Min Bae

    2014-01-01

    Full Text Available Localized surface plasmon resonance (LSPR is a promising method for detecting antigen-antibody binding in label-free biosensors. In this study, the fabrication of a LSPR substrate with a gold nanodot array through the lift-off process of an alumina mask is reported. The substrate showed an extinction peak in its extinction spectrum, and the peak position was dependent on the height of the gold nanodot array, and the change of extinction peak with the height could be predicted by the numerical simulation. In addition, the peak position was observed to be red-shifted with the increasing RIU value of the medium surrounding the gold nanodot array. In particular, the peak position in the 10 nm thick gold nanodot array was approximately 710 nm in air, and the sensitivity, defined as the ratio of the shift of peak position to the RIU of the medium, was 323.6 nm/RIU. The fabrication procedure could be applied to fabricate the LSPR substrates with a large area.

  19. Longitudinal surface plasmon resonance assay enhanced by magnetosomes for simultaneous detection of Pefloxacin and Microcystin-LR in seafoods.

    Science.gov (United States)

    Sun, Xiulan; Wu, Longyun; Ji, Jian; Jiang, Donglei; Zhang, Yinzhi; Li, Zaijun; Zhang, Genyi; Zhang, Hongxia

    2013-09-15

    A simple longitudinal surface plasmon resonance (LSPR) assay for the simultaneous detection of Pefloxacin and Microcystin-LR in seafoods has been developed for the first time using antibody-functionalized gold nanorods as signal probes and antigen-ovalbumin modified biological magnetosomes as signal amplification probes. The gold nanorods exhibit two different LSPR peaks, at around 695nm and 863nm, the positions of which were sensitive to changes in the local environment but can be subjected to simultaneous UV-vis detection. The biological magnetosomes produced by the magnetotactic bacteria not only act as a substrate for the immobilization of artificial antigen, but also enable signal enhancement and rapid separation, because of good dispersivity, biocompatibility and superparamagnetic properties. Under optimal conditions, magnetosome-enhanced LSPR assays showed a good linear response over the range 1-20ngmL(-1) (R(2)=0.9978 and R(2)=0.9992) with little adsorption to Enrofloxacin, Sarafloxacin, Ciprofloxacin, Norfloxacin, Microcystin-RR, Microcystin-LW, and Microcystin-LF, and compared with magnetosome-free LSPR assays, the response signal was amplified 2.5-5.0 fold. Furthermore, LSPR assays were successful in the analysis of Pefloxacin and Microcystin-LR in naturally contaminated seafood samples and high recoveries were achieved. Indications are that this LSPR assay promises reliable simultaneous detection of Pefloxacin and Microcystin-LR in seafoods, and holds the potential of novel applications in exploiting this multiple simultaneous UV-vis detection. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Phase modification and surface plasmon resonance of Au/WO{sub 3} system

    Energy Technology Data Exchange (ETDEWEB)

    Bose, R. Jolly; Kavitha, V.S. [Department of Optoelectronics, University of Kerala, Kariyavattom, Thiruvananthapuram 691574, Kerala (India); Sudarsanakumar, C. [School of Pure and Applied Physics, Mahatma Gandhi University, Priyadarshini Hills, Kottayam 686560, Kerala (India); Pillai, V.P. Mahadevan, E-mail: vpmpillai9@gmail.com [Department of Optoelectronics, University of Kerala, Kariyavattom, Thiruvananthapuram 691574, Kerala (India)

    2016-08-30

    Highlights: • We have investigated the role of gold as catalyst and nucleation centers, for the crystallization and phase modification of tungsten oxide, in Au/WO{sub 3} matrix. • The phase change from triclinic WO{sub 3} to monoclinic W{sub 18}O{sub 49} is found to enhance with gold incorporation. • The surface plasmon resonance is observed in gold/tungsten oxide system with the appearance of an absorption band near the wavelength 604 nm. - Abstract: We report the action of gold as catalyst for the modification of phase from triclinic WO{sub 3} to monoclinic W{sub 18}O{sub 49} and nucleation centre for the formation of W{sub 18}O{sub 49} phase, in gold incorporated tungsten oxide films prepared by RF magnetron sputtering technique. A new band is observed near 925 cm{sup −1} in the Raman spectra of gold incorporated tungsten oxide films which is not observed in the pure tungsten oxide film. The intensity of this band enhances with gold content. A localized surface plasmon resonance (LSPR) band is observed near the wavelength 604 nm in gold incorporated tungsten oxide films. The integrated intensities of LSPR band and Raman band (∼925 cm{sup −1}) can be used for sensing the quantity of gold in the Au/WO{sub 3} matrix.

  1. 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.

  2. Fabrication of fiber-optic localized surface plasmon resonance sensor and its application to detect antibody-antigen reaction of interferon-gamma

    Science.gov (United States)

    Jeong, Hyeon-Ho; Erdene, Norov; Lee, Seung-Ki; Jeong, Dae-Hong; Park, Jae-Hyoung

    2011-12-01

    A fiber-optic localized surface plasmon (FO LSPR) sensor was fabricated by gold nanoparticles (Au NPs) immobilized on the end-face of an optical fiber. When Au NPs were formed on the end-face of an optical fiber by chemical reaction, Au NPs aggregation occurred and the Au NPs were immobilized in various forms such as monomers, dimers, trimers, etc. The component ratio of the Au NPs on the end-face of the fabricated FO LSPR sensor was slightly changed whenever the sensors were fabricated in the same condition. Including this phenomenon, the FO LSPR sensor was fabricated with high sensitivity by controlling the density of Au NPs. Also, the fabricated sensors were measured for the resonance intensity for the different optical systems and analyzed for the effect on sensitivity. Finally, for application as a biosensor, the sensor was used for detecting the antibody-antigen reaction of interferon-gamma.

  3. 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.

  4. 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.

  5. All-optical switching of localized surface plasmon resonance in single gold nanosandwich using GeSbTe film as an active medium

    Science.gov (United States)

    Hira, T.; Homma, T.; Uchiyama, T.; Kuwamura, K.; Kihara, Y.; Saiki, T.

    2015-01-01

    Localized surface plasmon resonance (LSPR) switching was investigated in a Au/GeSbTe/Au nanosandwich as a key active element for plasmonic integrated circuits and devices. Near-infrared single-particle spectroscopy was conducted to examine the interaction of a Au nanorod (AuNR) and Au film, between which a GeSbTe layer was incorporated as an active phase-change media. Numerical calculation revealed that hybridized modes of the AuNR and Au film exhibit a significant change of scattering intensity with the phase change. In particular, the antisymmetric (magnetic resonance) mode can be modulated effectively by the extinction coefficient of GST, as well as its refractive index. Experimental demonstration of the switching operation was performed by alternate irradiation with a picosecond pulsed laser for amorphization and a continuous wave laser for crystallization. Repeatable modulation was obtained by monitoring the scattering light around the LSPR peak at λ = 1070 nm.

  6. All-optical switching of localized surface plasmon resonance in single gold nanosandwich using GeSbTe film as an active medium

    Energy Technology Data Exchange (ETDEWEB)

    Hira, T.; Homma, T.; Uchiyama, T.; Kuwamura, K.; Kihara, Y.; Saiki, T. [Graduate School of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku, Yokohama, Kanagawa 223-8522 (Japan)

    2015-01-19

    Localized surface plasmon resonance (LSPR) switching was investigated in a Au/GeSbTe/Au nanosandwich as a key active element for plasmonic integrated circuits and devices. Near-infrared single-particle spectroscopy was conducted to examine the interaction of a Au nanorod (AuNR) and Au film, between which a GeSbTe layer was incorporated as an active phase-change media. Numerical calculation revealed that hybridized modes of the AuNR and Au film exhibit a significant change of scattering intensity with the phase change. In particular, the antisymmetric (magnetic resonance) mode can be modulated effectively by the extinction coefficient of GST, as well as its refractive index. Experimental demonstration of the switching operation was performed by alternate irradiation with a picosecond pulsed laser for amorphization and a continuous wave laser for crystallization. Repeatable modulation was obtained by monitoring the scattering light around the LSPR peak at λ = 1070 nm.

  7. 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.

  8. Optical Fiber Sensor Based on Localized Surface Plasmon Resonance Using Silver Nanoparticles Photodeposited on the Optical Fiber End

    Science.gov (United States)

    Ortega-Mendoza, J. Gabriel; Padilla-Vivanco, Alfonso; Toxqui-Quitl, Carina; Zaca-Morán, Placido; Villegas-Hernández, David; Chávez, Fernando

    2014-01-01

    This paper reports the implementation of an optical fiber sensor to measure the refractive index in aqueous media based on localized surface plasmon resonance (LSPR). We have used a novel technique known as photodeposition to immobilize silver nanoparticles on the optical fiber end. This technique has a simple instrumentation, involves laser light via an optical fiber and silver nanoparticles suspended in an aqueous medium. The optical sensor was assembled using a tungsten lamp as white light, a spectrometer, and an optical fiber with silver nanoparticles. The response of this sensor is such that the LSPR peak wavelength is linearly shifted to longer wavelengths as the refractive index is increased, showing a sensitivity of 67.6 nm/RIU. Experimental results are presented. PMID:25302813

  9. Growth mechanisms and origin of localized surface plasmon resonance coupled exciton effects in Cu2_xS thin films

    Energy Technology Data Exchange (ETDEWEB)

    Savariraj, Dennyson A.; Kim, Hee-Je; Viswanathan, Kodakkal K.; Vijayakumar, M.; Prabakar, Kandasamy

    2016-02-15

    Cu2-xS thin films prepared by template free single step wet chemical method on fluorine doped tin oxide substrate without any surfactant exhibts localized surface plasmon resonance (LSPR) coupled exciton effects. Cu2-xS thin films of unique surface morphology and free carrier density due to copper vacancy is controlled by the growth temperature and time. These selectively grown Cu2-xS thin films possess tunable band gap (2.6 - 1.4 eV) due to quantum size effect. Eventhough, all the samples show satellite peak in the X-ray photoelectron spectra due to Cu vacancies, only the samples with higher oxygen concentration show LSPR in the near infrared region.

  10. Photocurrent enhancement by surface plasmon resonance of silver nanoparticles in highly porous dye-sensitized solar cells.

    Science.gov (United States)

    Jeong, Nak Cheon; Prasittichai, Chaiya; Hupp, Joseph T

    2011-12-06

    Localized surface plasmon resonance (LSPR) by silver nanoparticles that are photochemically incorporated into an electrode-supported TiO(2) nanoparticulate framework enhances the extinction of a subsequently adsorbed dye (the ruthenium-containing molecule, N719). The enhancement arises from both an increase in the dye's effective absorption cross section and a modest increase in the framework surface area. Deployment of the silver-modified assembly as a photoanode in dye-sensitized solar cells leads to light-to-electrical energy conversion with an overall efficiency of 8.9%. This represents a 25% improvement over the performance of otherwise identical solar cells lacking corrosion-protected silver nanoparticles. As one would expect based on increased dye loading and electromagnetic field enhanced (LSPR-enhanced) absorption, the improvement is manifested chiefly as an increase in photocurrent density ascribable to improved light harvesting.

  11. Optical fiber sensor based on localized surface plasmon resonance using silver nanoparticles photodeposited on the optical fiber end.

    Science.gov (United States)

    Ortega-Mendoza, J Gabriel; Padilla-Vivanco, Alfonso; Toxqui-Quitl, Carina; Zaca-Morán, Placido; Villegas-Hernández, David; Chávez, Fernando

    2014-10-09

    This paper reports the implementation of an optical fiber sensor to measure the refractive index in aqueous media based on localized surface plasmon resonance (LSPR). We have used a novel technique known as photodeposition to immobilize silver nanoparticles on the optical fiber end. This technique has a simple instrumentation, involves laser light via an optical fiber and silver nanoparticles suspended in an aqueous medium. The optical sensor was assembled using a tungsten lamp as white light, a spectrometer, and an optical fiber with silver nanoparticles. The response of this sensor is such that the LSPR peak wavelength is linearly shifted to longer wavelengths as the refractive index is increased, showing a sensitivity of 67.6 nm/RIU. Experimental results are presented.

  12. Optical Fiber Sensor Based on Localized Surface Plasmon Resonance Using Silver Nanoparticles Photodeposited on the Optical Fiber End

    Directory of Open Access Journals (Sweden)

    J. Gabriel Ortega-Mendoza

    2014-10-01

    Full Text Available This paper reports the implementation of an optical fiber sensor to measure the refractive index in aqueous media based on localized surface plasmon resonance (LSPR. We have used a novel technique known as photodeposition to immobilize silver nanoparticles on the optical fiber end. This technique has a simple instrumentation, involves laser light via an optical fiber and silver nanoparticles suspended in an aqueous medium. The optical sensor was assembled using a tungsten lamp as white light, a spectrometer, and an optical fiber with silver nanoparticles. The response of this sensor is such that the LSPR peak wavelength is linearly shifted to longer wavelengths as the refractive index is increased, showing a sensitivity of 67.6 nm/RIU. Experimental results are presented.

  13. 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.

  14. 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...

  15. A Physicochemical Investigation of the Localized Surface Plasmon Resonance of Silver Nanoparticles

    Science.gov (United States)

    McClary, Felicia Ann

    Observations of time dependent enhancements in the absorbance spectra of citrate3- stabilized silver nanoparticles (AgNPs), led to chemical optimization, for the control and reproducible synthesis of AgNP suspensions, with enhanced localized surface plasmon resonance (LSPR). Optimization is executed by microwave thermochemical reduction to synthesize stoichiometrically controlled AgNPs. The mass action study of citrate 3-/AgNPs show a linear growth in LSPR, approaching a 5:1, citrate 3-/Ag0, stoichiometry. LSPR enhancements result from maximum citrate3- electrostatic stabilization, leading to stable and separated AgNPs. Stoichiometries greater than 5:1, show a decay in plasmon absorbance as a function of the decreased particle concentration, and weakened stabilizing layer. At the largest stoichiometry, 10:1, the decay in LSPR and 31% Ag+ reduction, suggests the preference for Ag n+-citrate3-, metal-ligand complexes. AgNP surface charge, determined by zeta potential measurements, approach 0 mV, leading to the destabilizing effect of high citrate 3- concentrations, and increased hydrodynamic diameters, 65 nm, at 10:1. Also, slowed reaction constants at 10:1, confirm the influence of citrate 3- concentration toward Agn+-citrate 3- complexes; also noted by a decrease in chemical reactivity toward pyridine. Measured by surface enhanced Raman scattering (SERS), no reactivity toward pyridine is observed for 9:1 and 10:1. The largest chemical influence to pyridine is noted for 3:1 and 5:1. This reactivity is further evaluated using Cd2+, demonstrating a rapid plasmon decay of citrate 3-/AgNPs, resulting from an available carboxyl functional group at the surface of the nanoparticle, assigned by X-ray photoelectron spectroscopy (XPS), and not observed for ethylene glycol (EG) stabilized AgNPs. Similar reactivity with an organic molecule, 4, 5-diazafluoren-9-one (dafone), along with a 2 eV (46 kcal/mol) increase in O 1s XPS binding energy in EG/AgNPs, suggest the presence of

  16. 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.

  17. 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...

  18. 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...

  19. 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.

  20. 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

  1. 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

  2. Preparation of core-shell Ag@CeO2 nanocomposite by LSPR photothermal induced interface reaction.

    Science.gov (United States)

    Zhong, H X; Wei, Y; Yue, Y Z; Zhang, L H; Liu, Y

    2016-04-01

    The core-shell structure of Ag@CeO2 was prepared by a novel and facile method, which was based on the photothermal effect of localized surface plasmon resonance (LSPR). Nanoparticles (NPs) of Ag were dispersed in a solution containing citric acid, ethylene glycol and cerium nitrate, then under irradiation, Ag NPs generated heat from LSPR and the heat-induced polymerization reaction in the interface between Ag and the sol resulted in cerium gel formation only on the surface of the Ag NPs. After calcination, Ag@CeO2 was successfully obtained, then Ag@CeO2/SiO2 was prepared by loading Ag@CeO2 on SiO2. The resultant catalyst exhibited favorable activity and stability for CO oxidation. The preparation method proposed here should be extendable to other composites with metallic cores and oxide shells in which the metallic nanoparticle possesses LSPR properties.

  3. 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.

  4. 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.

  5. 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.

  6. An enhanced LSPR fiber-optic nanoprobe for ultrasensitive detection of protein biomarkers.

    Science.gov (United States)

    Sanders, Mollye; Lin, Yongbin; Wei, Jianjun; Bono, Taylor; Lindquist, Robert G

    2014-11-15

    A miniaturized, localized surface plasmon resonance (LSPR)-coupled fiber-optic (FO) nanoprobe is reported as a biosensor that is capable of label-free, sensitive detection of a cancer protein biomarker, free prostate specific antigen (f-PSA). The biosensor is based on the LSPR at the reusable dielectric-metallic hybrid interface with a robust, gold nano-disk array at the fiber end facet that is directly fabricated using EBL and metal lift-off process. The f-PSA has been detected with a mouse anti-human PSA monoclonal antibody (mAb) as a specific receptor linked with a self-assembled monolayer at the LSPR-FO facet surfaces. Experimental investigation and data analysis found near field refractive index (RI) sensitivity at ~226 nm/RIU with current LSPR-FO nanoprobe, and demonstrated the lowest limit of detection (LOD) at 100 fg/mL (~3 fM) of f-PSA in PBS solutions. The control experimentation using 5mg/mL bovine serum albumin in PBS and nonspecific surface test shows the excellent specificity and selectivity in the detection of f-PSA in PBS. These results present important progress towards a miniaturized, multifunctional fiber-optic technology that integrates informational communication and sensing function for developing a high performance, label-free, point-of-care (POC) device.

  7. 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

    Hollow reduced-symmetry resonant plasmonic nanostructures possess pronounced tunable optical resonances in the UV-vis-IR range, being a promising platform for advanced nanophotonic devices. However, the present fabrication approaches require several consecutive technological steps to produce such nanostructures, making their large-scale fabrication rather time-consuming and expensive. Here, we report on direct single-step fabrication of large-scale arrays of hollow parabolic- and cone-shaped nanovoids in silver and gold thin films, using single-pulse femtosecond nanoablation at high repetition rates. The lateral and vertical size of such nanovoids was 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.Hollow reduced-symmetry resonant plasmonic nanostructures possess pronounced tunable optical resonances in the UV-vis-IR range, being a promising platform for advanced nanophotonic devices. However, the present fabrication approaches require several consecutive technological steps to produce such nanostructures, making their large-scale fabrication rather time-consuming and expensive. Here, we report on direct single-step fabrication of large-scale arrays of hollow parabolic- and cone-shaped nanovoids in silver and gold thin films, using single-pulse femtosecond nanoablation at high repetition rates. The lateral and vertical size of such nanovoids was

  8. 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.

  9. 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.

  10. Development of a molecularly imprinted polymer based surface plasmon resonance sensor for theophylline monitoring

    Science.gov (United States)

    Zheng, Rui; Cameron, Brent D.

    2011-03-01

    Molecularly imprinted polymer (MIP) thin films and surface plasmon resonance (SPR) sensing technologies were combined to develop a novel sensing platform for monitoring real-time theophylline concentration, which is a compound of interest in environmental monitoring and a molecular probe for phenotyping certain cytochrome P450 enzymes. The MIPs hydrogel is easy to synthesize and provides shape-selective recognition with high affinity to specific target molecules. Different polymerization formulas were tested and optimized. The influence of the monomer sensitive factors were addressed by SPR. SPR is an evanescent wave optics based sensing technique that is suitable for real-time and label free sensing purposes. Gold nanorods (Au NRs) were uniformly immobilized onto a SPR sensing surface for the construction of a fiber optics based prism-free localized SPR (LSPR) measurement. This technique can be also applied to assess the activities of other small organic molecules by adjusting the polymerization formula, thus, this approach also has many other potential applications.

  11. Fabrication of gold nanorods with tunable longitudinal surface plasmon resonance peaks by reductive dopamine.

    Science.gov (United States)

    Su, Gaoxing; Yang, Chi; Zhu, Jun-Jie

    2015-01-20

    Hydroxyphenol compounds are often used as reductants in controlling the growth of nanoparticles. Herein, dopamine was used as an effective reductant in seed-mediated synthesis of gold nanorods (GNRs). The as-prepared GNRs (83 × 16 nm) were monodisperse and had a high degree of purity. The conversion ratio from gold ions to GNRs was around 80%. In addition, dopamine worked as an additive. At a very low concentration of hexadecyltrimethylammonium bromide (CTAB; 0.025 M), thinner and shorter GNRs (60 × 9 nm) were successfully prepared. By regulating the concentration of silver ions, CTAB, seeds, and reductant, GNRs with longitudinal surface plasmon resonance (LSPR) peaks ranging from 680 to 1030 nm were synthesized. The growth process was tracked using UV-vis-NIR spectroscopy, and it was found that a slow growth rate was beneficial to the formation of GNRs.

  12. Gold dimer nanoantenna with slanted gap for tunable LSPR and improved SERS

    KAUST Repository

    Kessentini, Sameh

    2014-02-13

    We focus on improving the surface-enhanced Raman scattering (SERS) of dimer nanoantenna by tailoring the shape of the coupled nanoantennas extremities from rounded to straight or slanted ones. A numerical model based on the discrete dipole approximation method-taking into account periodicity, adhesion layer, and roughness-is first validated by comparison with localized surface plasmon resonance (LSPR) and SERS experiments on round-edged dimer nanoantennas and then used to investigate the effect of the straight or slanted gap in the dimer antenna. Simulations show that both LSPR and SERS can be tuned by changing the gap slanting angle. The SERS enhancement factor can also be improved by 2 orders of magnitude compared to the one reached using a rounded gap. Therefore, the slanting angle can be used as a new control parameter in the design of SERS substrates to guarantee stronger field confinement and higher sensitivity, especially as its feasibility is demonstrated. © 2014 American Chemical Society.

  13. 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.

  14. LSPR properties of metal nanoparticles adsorbed at a liquid-liquid interface.

    Science.gov (United States)

    Yang, Zhilin; Chen, Shu; Fang, Pingping; Ren, Bin; Girault, Hubert H; Tian, Zhongqun

    2013-04-21

    Unlike the solid-air and solid-liquid interfaces, the optical properties of metal nanoparticles adsorbed at the liquid-liquid interface have not been theoretically exploited to date. In this work, the three dimensional finite difference time domain (3D-FDTD) method is employed to clarify the localized surface plasmon resonance (LSPR) based optical properties of gold nanoparticles (NPs) adsorbed at the water-oil interface, including near field distribution, far field absorption and their relevance. The LSPR spectra of NPs located at a liquid-liquid interface are shown to differ significantly from those in a uniform liquid environment or at the other interfaces. The absorption spectra exhibit two distinct LSPR peaks, the positions and relative strengths of which are sensitive to the dielectric properties of each liquid and the exact positions of the NPs with respect to the interface. Precise control of the particles' position and selection of the appropriate wavelength of the excitation laser facilitates the rational design and selective excitation of localized plasmon modes for interfacial NPs, a necessary advance for the exploration of liquid-liquid interfaces via surface enhanced Raman spectroscopy (SERS). According to our calculations, the SERS enhancement factor for Au nanosphere dimers at the water-oil interface can be as high as 10(7)-10(9), implying significant promise for future investigations of interfacial structure and applications of liquid-liquid interfaces towards chemical analysis.

  15. Label-free detection of 3-nitro-l-tyrosine with nickel-doped graphene localized surface plasmon resonance biosensor.

    Science.gov (United States)

    Ng, Siu Pang; Qiu, Guangyu; Ding, Ning; Lu, Xiaoqing; Wu, Chi-Man Lawrence

    2017-03-15

    3-nitro-l-tyrosine (3-NT) is believed to be a biomarker of neurodegenerative diseases and metal doped graphene possess exceptionally high binding energy of 3-NT with metal-nitro chemisorption. Here we report a novel label-free detection scheme of 3-NT via nickel-doped graphene (NDG) as the functionalized receptor on our phase detecting localized surface plasmon resonance (LSPR) biosensor. When compared with reported 3-NT immunoassay with enzyme-linked immunosorbent assay (ELISA), our NDG-LSPR platform offers two advantages i.e. 1) label-free and 2) capture of 3-NT by direct chemisorption. Our limit of detection for 3-NT in PBS was found to be 0.13pg/ml and the linear dynamic range of response was from 0.5pg/ml to 1ng/ml, i.e. four orders of magnitude. The specificity of our NDG receptor to 3-NT was also verified with l-tyrosine of equivalent concentrations in PBS and diluted human serum, for which the NDG receptor shows negligible responses. In addition, the adsorption of 3-NT and l-tyrosine to the NDG receptor were also investigated by atomic force microscopy and further verified by surface enhanced Raman spectroscopy. Therefore, our NDG-LSPR biosensor competes favorably against ELISA and we believe it should be an attractive and economical solution to early diagnostic of 3-NT related disorders for clinical applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Systematic control of edge length, tip sharpness, thickness, and localized surface plasmon resonance of triangular Au nanoprisms

    Science.gov (United States)

    Noda, Yuta; Hayakawa, Tomokatsu

    2016-10-01

    Triangular gold (Au) nanoprisms of various sizes were synthesized in a controlled way using a modified three-step seed-mediated method with different volumes of starting seed solution and subsequent first step's growth solution. The structures and optical properties of the triangular Au nanoprisms were investigated using transmission electron microscopy (TEM), atomic force microscopy, and UV-Vis-NIR spectrophotometry. The Au nanoprisms synthesized also varied in optical response frequency of localized surface plasmon resonance (LSPR) owing to electric dipole polarizations of the Au nanoprisms. This variation depended nonlinearly on the volume of the seed solution. From optical extinction spectra and careful TEM observations, the dipole LSPR peak frequency was found to be linearly proportional to the edge length of the Au nanoprisms. Consequently, it was experimentally shown that the LSPR optical response frequency of their colloidal solutions could be controlled in the near-infrared region (700-1200 nm), corresponding to an edge length of 40-180 nm of the Au nanoprisms. It was also demonstrated that the tip sharpness of triangular Au nanoprisms was improved by using fine Au seeds instead of coarse Au seeds, and the resulting Au nanoprisms were smaller and thinner. A formation mechanism of triangular Au nanoprisms shall also be discussed with a prospect of synthesizing very tiny Au nanoprisms.

  17. Plasmonic fluorescence enhancement of DBMBF2 monomers and DBMBF2-toluene exciplexes using al-hole arrays

    NARCIS (Netherlands)

    Schmidt, T.M.; Bochenkov, V.E.; Espinoza, J.D.A.; Smits, E.C.P.; Muzafarov, A.M.; Kononevich, Y.N.; Sutherland, D.S.

    2014-01-01

    The optical properties of aluminum hole arrays fabricated via colloidal lithography were investigated. By tuning the hole diameter and hole spacing independently, their influence on the Bloch wave-surface plasmon polariton (BW-SPP) and localized surface plasmon resonances resonances (LSPR) could be

  18. 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.

  19. 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.

  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. Evolution of the surface plasmon resonance of Au:TiO{sub 2} nanocomposite thin films with annealing temperature

    Energy Technology Data Exchange (ETDEWEB)

    Borges, J., E-mail: joelborges@fisica.uminho.pt [Universidade do Minho, Centro/Departamento de Física (Portugal); Buljan, M.; Sancho-Parramon, J.; Bogdanovic-Radovic, I.; Siketic, Z. [Rudjer Boskovic Institute (Croatia); Scherer, T.; Kübel, C. [Karlsruhe Institute of Technology (KIT), Institute of Nanotechnology (INT) and Karlsruhe Nano Micro Facility - KNMF (Germany); Bernstorff, S. [Elettra-Sincrotrone Trieste (Italy); Cavaleiro, A. [University of Coimbra, SEG-CEMUC, Mechanical Engineering Department (Portugal); Vaz, F.; Rolo, A. G. [Universidade do Minho, Centro/Departamento de Física (Portugal)

    2014-12-15

    This paper reports on the changes in the structural and morphological features occurring in a particular type of nanocomposite thin-film system, composed of Au nanoparticles (NPs) dispersed in a host TiO{sub 2} dielectric matrix. The structural and morphological changes, promoted by in-vacuum annealing experiments of the as-deposited thin films at different temperatures (ranging from 200 to 800 °C), resulted in a well-known localized surface plasmon resonance (LSPR) phenomenon, which gave rise to a set of different optical responses that can be tailored for a wide number of applications, including those for optical-based sensors. The results show that the annealing experiments enabled a gradual increase of the mean grain size of the Au NPs (from 2 to 23 nm), and changes in their distributions and separations within the dielectric matrix. For higher annealing temperatures of the as-deposited films, a broad size distribution of Au NPs was found (sizes up to 100 nm). The structural conditions necessary to produce LSPR activity were found to occur for annealing experiments above 300 °C, which corresponded to the crystallization of the gold NPs, with an average size strongly dependent on the annealing temperature itself. The main factor for the promotion of LSPR was the growth of gold NPs and their redistribution throughout the host matrix. On the other hand, the host matrix started to crystallize at an annealing temperature of about 500 °C, which is an important parameter to explain the shift of the LSPR peak position to longer wavelengths, i.e. a red-shift.

  2. 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.

  3. 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.

  4. 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...

  5. 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.

  6. 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.

  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. 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.

  12. 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.

  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. 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.

  15. Membrane-protein binding measured with solution-phase plasmonic nanocube sensors.

    Science.gov (United States)

    Wu, Hung-Jen; Henzie, Joel; Lin, Wan-Chen; Rhodes, Christopher; Li, Zhu; Sartorel, Elodie; Thorner, Jeremy; Yang, Peidong; Groves, Jay T

    2012-12-01

    We describe a solution-phase sensor of lipid-protein binding based on localized surface plasmon resonance (LSPR) of silver nanocubes. When silica-coated nanocubes are mixed in a suspension of lipid vesicles, supported membranes spontaneously assemble on their surfaces. Using a standard laboratory spectrophotometer, we calibrated the LSPR peak shift due to protein binding to the membrane surface and then characterized the lipid-binding specificity of a pleckstrin homology domain protein.

  16. 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.

  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. Increasing the spectral shifts in LSPR biosensing using DNA-functionalized gold nanorods in a competitive assay format for the detection of interferon-γ.

    Science.gov (United States)

    Lin, Ding-Zheng; Chuang, Po-Chun; Liao, Pei-Chen; Chen, Jung-Po; Chen, Yih-Fan

    2016-07-15

    We demonstrate an approach that utilizes DNA-functionalized gold nanorods (AuNRs) in an indirect competitive assay format to increase the spectra shift in localized surface plasmon resonance (LSPR) biosensing. We use interferon gamma (IFN-γ) as a model analyte to demonstrate the feasibility of our detection method. The LSPR chips with periodic gold nanodot arrays are fabricated using a thermal lithography process and are functionalized with IFN-γ aptamers for detection. The DNA-functionalized AuNRs and IFN-γ compete with each other to bind to the aptamers during detection, and the spectra shifts are mainly caused by the AuNRs rather than IFN-γ. When using our approach, the target molecules do not need to be captured by two capture ligands simultaneously during detection and thus do not require multiple binding sites. Both experiments and finite-difference time-domain (FDTD) simulations show that making the AuNRs as close to the chip surface as possible is very critical for increasing LSPR shifts, and the simulated results also show that the orientation of the AuNR affects the plasmon coupling between the gold nanodots on the chip surface and the nearby AuNRs. Although only the detection of IFN-γ is demonstrated in this study, we expect that the LSPR biosensing method can be applied to label-free detection of a variety of molecules as long as suitable aptamers are available.

  20. 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....

  1. 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

  2. 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...

  3. 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.

  4. 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.

  5. 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}.

  6. 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.

  7. 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

  8. Surface Plasmon-Assisted Solar Energy Conversion.

    Science.gov (United States)

    Dodekatos, Georgios; Schünemann, Stefan; Tüysüz, Harun

    2016-01-01

    The utilization of localized surface plasmon resonance (LSPR) from plasmonic noble metals in combination with semiconductors promises great improvements for visible light-driven photocatalysis, in particular for energy conversion. This review summarizes the basic principles of plasmonic photocatalysis, giving a comprehensive overview about the proposed mechanisms for enhancing the performance of photocatalytically active semiconductors with plasmonic devices and their applications for surface plasmon-assisted solar energy conversion. The main focus is on gold and, to a lesser extent, silver nanoparticles in combination with titania as semiconductor and their usage as active plasmonic photocatalysts. Recent advances in water splitting, hydrogen generation with sacrificial organic compounds, and CO2 reduction to hydrocarbons for solar fuel production are highlighted. Finally, further improvements for plasmonic photocatalysts, regarding performance, stability, and economic feasibility, are discussed for surface plasmon-assisted solar energy conversion.

  9. 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.

  10. LSPR enhanced gasoline sensing with a U-bent optical fiber

    Science.gov (United States)

    Paul, D.; Dutta, S.; Biswas, R.

    2016-08-01

    We report here a gasoline sensor utilizing localized surface plasmon resonance (LSPR) phenomenon of metal nanoparticles (NPs) with a U-bent optical fiber. The optical response of the noble metal NPs upon interaction with gasoline has been simulated and experimentally demonstrated. The increase in gasoline vapor over a period of time induces a change in the refractive index of the adjacent medium of nanoparticle colloids, adhering to the probe, and thus the variation has been observed accordingly. This change in the refractive index in the close proximity to noble metals NPs produces a measurable variation in the output signal that has been correlated with the increase in the concentration of gasoline. The sensor provides better sensitivity corresponding to AgNPs when compared to AuNPs. However, in terms of stability, AuNPs-based LSPR performs better than the AgNPs-based plasmonic response. The present sensing set-up offers a light weight, robust and easy to implement platform that has potent application in detecting volatile liquids very effectively.

  11. 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.

  12. 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.

  13. Surface scattering contribution to the plasmon width in embedded Ag nanospheres

    CERN Document Server

    Monreal, R Carmina; Antosiewicz, Tomasz J

    2014-01-01

    Nanometer-sized metal particles exhibit broadening of the localized surface plasmon resonance (LSPR) in comparison to its value predicted by the classical Mie theory. Using our model for the LSPR dependence on non-local surface screening and size quantization, we quantitatively relate the observed plasmon width to the nanoparticle radius $R$ and the permittivity of the surrounding medium $\\epsilon_m$. For Ag nanospheres larger than 8 nm only the non-local dynamical effects occurring at the surface are important and, up to a diameter of 25 nm, dominate over the bulk scattering mechanism. Qualitatively, the LSPR width is inversely proportional to the particle size and has a nonmonotonic dependence on the permittivity of the host medium, exhibiting for Ag a maximum at $\\epsilon_m\\approx2.5$. Our calculated LSPR width is compared with recent experimental data.

  14. 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,...

  15. Au-Ag-Au double shell nanoparticles-based localized surface plasmon resonance and surface-enhanced Raman scattering biosensor for sensitive detection of 2-mercapto-1-methylimidazole.

    Science.gov (United States)

    Liao, Xue; Chen, Yanhua; Qin, Meihong; Chen, Yang; Yang, Lei; Zhang, Hanqi; Tian, Yuan

    2013-12-15

    In this paper, Au-Ag-Au double shell nanoparticles were prepared based on the reduction of the metal salts HAuCl4 and AgNO3 at the surface of seed particles. Due to the synergistic effect between Au and Ag, the hybrid nanoparticles are particularly stable and show excellent performances on the detection of 2-mercapto-1-methylimidazole (methimazole). The binding of target molecule at the surface of Au-Ag-Au double shell nanoparticles was demonstrated based on both localized surface plasmon resonance (LSPR) and surface-enhanced Raman scattering (SERS) spectra. The LSPR intensity is directly proportional to the methimazole concentration in the range of 0.10-3.00×10(-7) mol L(-1). The SERS spectrum can be applied in identification of methimazole molecule. The LSPR coupled with SERS based on the Au-Ag-Au double shell nanoparticles would be very attractive for the quantitative determination and qualitative analysis of the analytes in medicines.

  16. Controlling successive ionic layer absorption and reaction cycles to optimize silver nanoparticle-induced localized surface plasmon resonance effects on the paper strip

    Science.gov (United States)

    Lee, Jae-Chul; Kim, Wansun; Park, Hun-Kuk; Choi, Samjin

    2017-03-01

    This study investigates why a silver nanoparticle (SNP)-induced surface-enhanced Raman scattering (SERS) paper chip fabricated at low successive ionic layer absorption and reaction (SILAR) cycles leads to a high SERS enhancement factor (7 × 108) with an inferior nanostructure and without generating a hot spot effect. The multi-layered structure of SNPs on cellulose fibers, verified by magnified scanning electron microscopy (SEM) and analyzed by a computational simulation method, was hypothesized as the reason. The pattern of simulated local electric field distribution with respect to the number of SILAR cycles showed good agreement with the experimental Raman intensity, regardless of the wavelength of the excitation laser sources. The simulated enhancement factor at the 785-nm excitation laser source (2.8 × 109) was 2.5 times greater than the experimental enhancement factor (1.1 × 109). A 532-nm excitation laser source exhibited the highest maximum local electric field intensity (1.9 × 1011), particularly at the interparticle gap called a hot spot. The short wavelength led to a strong electric field intensity caused by strong electromagnetic coupling arising from the SNP-induced local surface plasmon resonance (LSPR) effects through high excitation energy. These findings suggest that our paper-based SILAR-fabricated SNP-induced LSPR model is valid for understanding SNP-induced LSPR effects.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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...

  7. Propagating and localized surface plasmon resonance sensing — A critical comparison based on measurements and theory

    Directory of Open Access Journals (Sweden)

    Jacqueline Jatschka

    2016-03-01

    The study demonstrated the capabilities of LSPR for sensing of molecular layers even in the lower nanometer dimension. For the detection of small (biomolecules, smaller particle diameters are favored regarding highest sensitivity. It also presents an approach to obtain refractive index and the thickness of a molecular film by analyzing the signal response of plasmonic sensors with metal nanoparticles. Moreover, an additional method for the improvement of the parameters' determination is introduced.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  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. Searching for Alternative Plasmonic Materials for Specific Applications

    Directory of Open Access Journals (Sweden)

    Amit Bansal

    2014-01-01

    Full Text Available The localized surface plasmon resonance (LSPR based optical properties such as light scattering, absorption, and extinction efficiencies of multimetallic and metal-semiconductor nanostructures will be studied. The effect of size, surrounding medium, interaction between the particles, composition of the particles, and substrate on LSPR peak position, its line width, and maxima of cross-sections will also be discussed to optimize the selected systems for various applications like plasmonic sensors and biomedical applications and to enhance the efficiency of solar cells. Therefore, by varying all these factors, the LSPR peak of multimetallic and metal-semiconductor nanostructures can be tuned over the entire UV-visible to infrared (IR region of the electromagnetic spectrum. Moreover the optical properties of underlying semiconductor materials can be enhanced by combining the semiconductor with noble metal nanoparticles.

  15. Nanogold plasmonic photocatalysis for organic synthesis and clean energy conversion.

    Science.gov (United States)

    Wang, Changlong; Astruc, Didier

    2014-01-01

    This review provides the basic concepts, an overall survey and the state-of-the art of plasmon-based nanogold photocatalysis using visible light including fundamental understanding and major applications to organic reactions and clean energy-conversion systems. First, the basic concepts of localized surface plasmon resonance (LSPR) are recalled, then the major preparation methods of AuNP-based plasmonic photocatalysts are reviewed. The major part of the review is dedicated to the latest progress in the application of nanogold plasmonic photocatalysis to organic transformations and energy conversions, and the proposed mechanisms are discussed. In conclusion, new challenges and perspectives are proposed and analyzed.

  16. Solar energy conversion with tunable plasmonic nanostructures for thermoelectric devices.

    Science.gov (United States)

    Xiong, Yujie; Long, Ran; Liu, Dong; Zhong, Xiaolan; Wang, Chengming; Li, Zhi-Yuan; Xie, Yi

    2012-08-01

    The photothermal effect in localized surface plasmon resonance (LSPR) should be fully utilized when integrating plasmonics into solar technologies for improved light absorption. In this communication, we demonstrate that the photothermal effect of silver nanostructures can provide a heat source for thermoelectric devices for the first time. The plasmonic band of silver nanostructures can be facilely manoeuvred by tailoring their shapes, enabling them to interact with photons in different spectral ranges for the efficient utilization of solar light. It is anticipated that this concept can be extended to design a photovoltaic-thermoelectric tandem cell structure with plasmonics as mediation for light harvesting.

  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. Radiation synthesized poly(n-vinyl-2-pyrrolidone)-stabilized-gold nanoparticles as LSPR-based optical sensor for mercury ions estimation

    Energy Technology Data Exchange (ETDEWEB)

    Misra, Nilanjal; Kumar, Virendra, E-mail: vkrawat75@gmail.com, E-mail: vkumar@barc.gov.in; Goel, Narender Kumar; Varshney, Lalit [Bhabha Atomic Research Centre, Radiation Technology Development Division (India)

    2015-07-15

    Poly(n-vinyl-2-pyrrolidone)-stabilized-gold nanoparticles (PVP-Au-NPs) have been synthesized via a green-{sup 60}Co-Gamma radiolytic route and employed as a localized surface plasmon resonance (LSPR)-based optical sensor for estimation of trace quantities of Hg{sup 2+} ion in aqueous solutions. The in situ generated PVP-Au-NPs were characterized using UV–vis spectroscopy, transmission electron microscopy, and particle size analysis techniques. Reaction conditions were optimized to obtain uniformly dispersed PVP-Au-NPs with average particle size of 7.1 ± 1.6 nm (±s), which exhibited a narrow LSPR band at ∼527 nm. The decrease in LSPR band intensity of PVP-Au-NPs with increase in Hg{sup 2+} ion concentration was found to be linear in the Hg{sup 2+} ion concentration range of 0–100 nM. The LSPR-based PVP-Au-NPs optical sensor system was found to be selective for Hg{sup 2+} and independent of interference from other metal ions such as Ca{sup 2+,} Cu{sup 2+}, Cd{sup 2+}, and Fe{sup 2+} up to a concentration of 500 nM.

  19. Exciton-plasmon Coupling and Electromagnetically Induced Transparency in Monolayer Semiconductors Hybridized with Ag Nanoparticles

    CERN Document Server

    Weijie, Zhao; Bo, Liu; Ivan, Verzhbitskiy; Shisheng, Li; Francesco, Giustiniano; Daichi, Kozawa; Ping, Loh Kian; Kazunari, Matsuda; Koichi, Okamoto; Rupert, Oulton F; Goki, Eda

    2016-01-01

    Hybrid systems of excitons strongly coupled to localized surface plasmons supported by metallic nanoparticles define a new approach to control light-matter interactions. Here, we report exciton-plasmon coupling in two-dimensional (2D) semiconductors, such as MoS2 and WS2, hybridized with silver nanoparticles. Prominent photoluminescence enhancement in monolayer MoS2 was observed with localized surface plasmon resonance (LSPR) tuned to the exciton resonance. By tuning the excitation energy, the contributions from near field enhancement and radiative emission rate enhancement via Purcell effect were resolved. Strong coherent dipole-dipole coupling between excitons and LSPR in resonant condition manifests as an electromagnetically induced transparency window in the extinction spectra of the localized surface plasmon. In this strong coupling regime a new quasi-particle, known as a plexciton, is expected to exhibit distinct properties, which exist in neither of the original particles. Our results demonstrate that ...

  20. 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.

  1. 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

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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.

  7. 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.

  8. 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

  9. 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...

  10. 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…

  11. 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

  12. 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.

  13. 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.

  14. Plasmonics analysis of nanostructures for bioapplications

    Science.gov (United States)

    Xie, Qian

    Plasmonics, the science and technology of the plasmons, is a rapidly growing field with substantial broader impact in numerous different fields, especially for bio-applications such as bio-sensing, bio-photonics and photothermal therapy. Resonance effects associated with plasmatic behavior i.e. surface Plasmon resonance (SPR) and localize surface Plasmon resonance (LSPR), are of particular interest because of their strong sensitivity to the local environment. In this thesis, plasmonic resonance effects are discussed from the basic theory to applications, especially the application in photothermal therapy, and grating bio-sensing. This thesis focuses on modeling different metallic nanostructures, i.e. nanospheres, nanorods, core-shell nanoparticles, nanotori and hexagonal closed packed nanosphere structures, to determine their LSPR wavelengths for use in various applications. Experiments regarding photothermal therapy using gold nanorods are described and a comparison is presented with results obtained from simulations. Lastly, experiments of grating-based plasmon-enhanced bio-sensing are also discussed. In chapter one, the physics of plasmonics is reviewed, including surface plasmon resonance (SPR) and localized surface plasmon resonance (LSPR). In the section on surface plasmon resonance, the physics behind the phenomenon is discussed, and also, the detection methods and applications in bio-sensing are described. In the section on localized surface plasmon resonance (LSPR), the phenomenon is described with respect to sub wavelength metallic nanoparticles. In chapter two, specific plasmonic-based bio-applications are discussed including plasmonic and magneto-plasmonic enhanced photothermal therapy and grating-based SPR bio-sening. In chapter three, which is the most important part in the thesis, optical modeling of different gold nanostructures is presented. The modeling tools used in this thesis are Comsol and custom developed Matlab programs. In Comsol, the

  15. 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

  16. 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.

  17. 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.

  18. Tunable Localized Surface Plasmon Resonance of Gold Nanoshell Particle%金纳米球壳结构局域表面等离子体共振调谐特性

    Institute of Scientific and Technical Information of China (English)

    张兴坊; 张腊梅; 范群芳; 廖艳林; 陈晓东; 毛庆和

    2011-01-01

    Tunable characteristics of the localized surface plasmon resonance (LSPR) peak of gold nanoshells are investigated numerically with Mie theory. The results show that, for a nanoshell with fixed inner radius, the LSPR peak of gold nanoshell may be controlled by changing the thickness of the shell to adjust the strength of the hybridization effect which makes the LSPR peak red-shift. As the ratio of the nanoshell thickness to the nanoshell inner radius decreases, the absorption component in whole extinction spectra for nanoshells with different inner radii all increases. In addition, when the hybridization effect is used to adjust the LSPR dipole peak position, the available maximum wavelength scope is determined by the nanoshell inner radius. The larger the inner radius is, the wider the available maximum wavelength scope is.%理论研究了金纳米球壳结构局域表面等离子体共振(LSPR)的调谐特性.结果表明,对于固定内径的球壳结构,利用杂化效应使得球壳结构可通过改变其厚度实现LSPR峰位的调控,并可保持较窄的谱宽;而对于不同内径的球壳,在LSPR调控过程中,随壳层厚度与球壳内半径比值的减小,吸收光谱在消光光谱中所占比例增大.不仅如此,利用杂化效应进行偶极峰位调控时所能获得的峰位调控范围与球壳内径有关,内径越大,所能获得的偶极峰位调控范围越大.

  19. Localized surface plasmon resonance-based hybrid Au-Ag nanoparticles for detection of Staphylococcus aureus enterotoxin B

    Science.gov (United States)

    Zhu, Shaoli; Du, ChunLei; Fu, Yongqi

    2009-09-01

    A triangular hybrid Au-Ag nanoparticles array was proposed for the purpose of biosensing in this paper. Constructing the hybrid nanoparticles, an Au thin film is capped on the Ag nanoparticles which are attached on glass substrate. The hybrid nanoparticles array was designed by means of finite-difference and time-domain (FDTD) algorithm-based computational numerical calculation and optimization. Sensitivity of refractive index of the hybrid nanoparticles array was obtained by the computational calculation and experimental detection. Moreover, the hybrid nanoparticles array can prevent oxidation of the pure Ag nanoparticles from atmosphere environment because the Au protective layer was deposited on top of the Ag nanoparticles so as to isolate the Ag particles from the atmosphere. We presented a novel surface covalent link method between the localized surface plasmon resonance (LSPR) effect-based biosensors with hybrid nanoparticles array and the detected target molecules. The generated surface plasmon wave from the array carries the biological interaction message into the corresponding spectra. Staphylococcus aureus enterotoxin B (SEB), a small protein toxin was directly detected at nanogramme per milliliter level using the triangular hybrid Au-Ag nanoparticles. Hence one more option for the SEB detection is provided by this way.

  20. Plasmon field effect transistor: A novel sensing platform for biomedical applications

    Science.gov (United States)

    Shokri Kojori, Hossein

    The interest in plasmons, associated with nanostructured metals, has remarkably increased in the past decade. A Recent improvement in fabrication techniques to create well-controlled nanostructures also contributed to the rapid development of plasmonic applications, such as meta-materials, nonlinear optics, photovoltaic devices, biomedical sensors, medical therapies and spectroscopy. The surface plasmon resonance (SPR) sensor is one of the successful applications, which is widely used in biomedical research. On the other hand, localized surface plasmon resonance (LSPR) is also widely studied in a broad range of applications. The distinct property of LSPR is a tailored and sharp absorption/scattering peaks depending on the shape and sizes of the metal nanostructures. In addition, plasmonics can enable integration of high speed optical circuit by taking the advantages from the current electronics and optics technologies. Thus, plasmonics is considered as a solution for the next generation systems that offers ultra-high speed data processing. In this dissertation, we will introduce a novel plasmon field effect transistor (FET) that enables direct detection and efficient amplification of plasmon energy. This FET has several advantages such as electrical isolation of plasmon absorber nanostructures from a sensing and drug screening. Currently, we have proof of concept for the antigen-antibody bonding using the plasmon field effect transistor. We will develop a multiplexing capable plasmon FET sensing platform by integrating an array of plasmon FETs with microfluidic channels to detect cancer biomarkers.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. Direct photocatalysis for organic synthesis by using plasmonic-metal nanoparticles irradiated with visible light.

    Science.gov (United States)

    Xiao, Qi; Jaatinen, Esa; Zhu, Huaiyong

    2014-11-01

    Recent advances in direct-use plasmonic-metal nanoparticles (NPs) as photocatalysts to drive organic synthesis reactions under visible-light irradiation have attracted great interest. Plasmonic-metal NPs are characterized by their strong interaction with visible light through excitation of the localized surface plasmon resonance (LSPR). Herein, we review recent developments in direct photocatalysis using plasmonic-metal NPs and their applications. We focus on the role played by the LSPR of the metal NPs in catalyzing organic transformations and, more broadly, the role that light irradiation plays in catalyzing the reactions. Through this, the reaction mechanisms that these light-excited energetic electrons promote will be highlighted. This review will be of particular interest to researchers who are designing and fabricating new plasmonic-metal NP photocatalysts by identifying important reaction mechanisms that occur through light irradiation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. Non-von Neumann computing using plasmon particles interacting with phase change materials (Conference Presentation)

    Science.gov (United States)

    Saiki, Toshiharu

    2016-09-01

    Control of localized surface plasmon resonance (LSPR) excited on metal nanostructures has drawn attention for applications in dynamic switching of plasmonic devices. As a reversible active media for LSPR control, chalcogenide phase-change materials (PCMs) such as GeSbTe (GST) are promising for high-contrast robust plasmonic switching. Owing to the plasticity and the threshold behavior during both amorphization and crystallization of PCMs, PCM-based LSPR switching elements possess a dual functionality of memory and processing. Integration of LSPR switching elements so that they interact with each other will allow us to build non-von-Neumann computing devices. As a specific demonstration, we discuss the implementation of a cellular automata (CA) algorithm into interacting LSPR switching elements. In the model we propose, PCM cells, which can be in one of two states (amorphous and crystalline), interact with each other by being linked by a AuNR, whose LSPR peak wavelength is determined by the phase of PCM cells on the both sides. The CA program proceeds by irradiating with a light pulse train. The local rule set is defined by the temperature rise in the PCM cells induced by the LSPR of the AuNR, which is subject to the intensity and wavelength of the irradiating pulse. We also investigate the possibility of solving a problem analogous to the spin-glass problem by using a coupled dipole system, in which the individual coupling strengths can be modified to optimize the system so that the exact solution can be easily reached. For this algorithm, we propose an implementation based on an idea that coupled plasmon particles can create long-range spatial correlations, and the interaction of this with a phase-change material allows the coupling strength to be modified.

  11. 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.

  12. 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.

  13. 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.

  14. 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...

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. Synthesis of oxocarbon-encapsulated gold nanoparticles with blue-shifted localized surface plasmon resonance by pulsed laser ablation in water with CO2 absorbers

    Science.gov (United States)

    Del Rosso, T.; Rey, N. A.; Rosado, T.; Landi, S.; Larrude, D. G.; Romani, E. C.; Freire Junior, F. L.; Quinteiro, S. M.; Cremona, M.; Aucelio, R. Q.; Margheri, G.; Pandoli, O.

    2016-06-01

    Colloidal suspensions of oxocarbon-encapsulated gold nanoparticles have been synthesized in a one-step procedure by pulsed-laser ablation (PLA) at 532 nm of a solid gold target placed in aqueous solution containing CO2 absorbers, but without any stabilizing agent. Multi-wavelength surface enhanced Raman spectroscopy allows the identification of adsorbed amorphous carbon and graphite, Au-carbonyl, Au coordinated CO2-derived bicarbonates/carbonates and hydroxyl groups around the AuNPs core. Scanning electron microscopy, energy dispersive x-ray analysis and high resolution transmission electron microscopy highlight the organic shell structure around the crystalline metal core. The stability of the colloidal solution of nanocomposites (NCs) seems to be driven by solvation forces and is achieved only in neutral or basic pH using monovalent hydroxide counter-ions (NaOH, KOH). The NCs are characterized by a blue shift of the localized surface plasmon resonance (LSPR) band typical of metal-ligand stabilization by terminal π-back bonding, attributed to a core charging effect caused by Au-carbonyls. Total organic carbon measurements detect the final content of organic carbon in the colloidal solution of NCs that is about six times higher than the value of the water solution used to perform PLA. The colloidal dispersions of NCs are stable for months and are applied as analytical probes in amino glycoside antibiotic LSPR based sensing.

  1. 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.

  2. Characteristics of localized surface plasmons excited on mixed monolayers composed of self-assembled Ag and Au nanoparticles.

    Science.gov (United States)

    Tanaka, Daisuke; Imazu, Keisuke; Sung, Jinwoo; Park, Cheolmin; Okamoto, Koichi; Tamada, Kaoru

    2015-10-07

    The fundamental characteristics of localized surface plasmon resonance (LSPR) excited on mixed monolayers composed of self-assembled Ag and Au nanoparticles (AgNPs and AuNPs, respectively) were investigated. Mixed monolayered films were fabricated at the air-water interface at different mixing ratios. The films retained their phase-segregated morphologies in which AuNPs formed several 10 to 100 nm island domains in a homogeneous AgNP matrix phase. The LSPR bands originating from the self-assembled domains shifted to longer wavelengths as the domain size increased, as predicted by a finite-difference time-domain (FDTD) simulation. The FDTD simulation also revealed that even an alternating-lattice-structured two-dimensional (2D) AgNP/AuNP film retained two isolated LSPR bands, revealing that the plasmon resonances excited on each particle did not couple even in a continuous 2D sheet, unlike in the homologous NP system. The fluorescence quenching test of Cy3 and Cy5 dyes confirmed that the independent functions of AuNPs and AgNPs remained in the mixed films, whereas the AuNPs exhibited significantly higher quenching efficiency for the Cy3 dye compared with AgNPs due to the overlap of the excitation/emission bands of the dyes with the AuNP LSPR band. Various applications can be considered using this nanoheterostructured plasmonic assembly to excite spatially designed, high-density LSPR on macroscopic surfaces.

  3. 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.

  4. 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.

  5. 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

  6. Plasmonic Paper as a Novel Chem/Bio Detection Platform

    Science.gov (United States)

    Tian, Limei

    The time varying electric field of electromagnetic (EM) radiation causes oscillation of conduction electrons of metal nanoparticles. The resonance of such oscillation, termed localized surface plasmon resonance (LSPR), falls into the visible spectral region for noble metals such as gold, silver and copper. LSPR of metal nanostructures is sensitive to numerous factors such as composition, size, shape, dielectric properties of surrounding medium, and proximity to other nanostructures (plasmon coupling). The sensitivity of LSPR to the refractive index of surrounding medium renders it an attractive platform for chemical and biological sensing. When the excitation light is in resonance with the plasmon frequency of the metal nanoparticle, it radiates a characteristic dipolar radiation causing a characteristic spatial distribution in which certain areas show higher EM field intensity, which is manifested as electromagnetic field enhancement. Surface enhanced Raman scattering (SERS) involves dramatic enhancement of the intensity of the Raman scattering from the analyte adsorbed on or in proximity to a nanostructured metal surface exhibiting such strong EM field enhancement. Both LSPR and SERS have been widely investigated for highly sensitive and label-free chemical & biological sensors. Most of the SERS/LSPR sensors demonstrated so far rely on rigid planar substrates (e.g., glass, silicon) owing to the well-established lithographic approaches, which are routinely employed for either fabrication or assembly of plasmonic nanotransducers. In many cases, their rigid nature results in low conformal contact with the sample and hence poor sample collection efficiency. We hypothesized that paper substrates are an excellent alternative to conventional rigid substrates to significantly improve the (multi-)functionality of LSPR/SERS substrates, dramatically simplify the fabrication procedures and lower the cost. The choice of paper substrates for the implementation of SERS/LSPR

  7. 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.

  8. 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.

  9. 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.

  10. Recent advancements in plasmon-enhanced promising third-generation solar cells

    Directory of Open Access Journals (Sweden)

    Thrithamarassery Gangadharan Deepak

    2017-01-01

    Full Text Available The unique optical properties possessed by plasmonic noble metal nanostructures in consequence of localized surface plasmon resonance (LSPR are useful in diverse applications like photovoltaics, sensing, non-linear optics, hydrogen generation, and photocatalytic pollutant degradation. The incorporation of plasmonic metal nanostructures into solar cells provides enhancement in light absorption and scattering cross-section (via LSPR, tunability of light absorption profile especially in the visible region of the solar spectrum, and more efficient charge carrier separation, hence maximizing the photovoltaic efficiency. This review discusses about the recent development of different plasmonic metal nanostructures, mainly based on Au or Ag, and their applications in promising third-generation solar cells such as dye-sensitized solar cells, quantum dot-based solar cells, and perovskite solar cells.

  11. Recent advancements in plasmon-enhanced promising third-generation solar cells

    Science.gov (United States)

    Thrithamarassery Gangadharan, Deepak; Xu, Zhenhe; Liu, Yanlong; Izquierdo, Ricardo; Ma, Dongling

    2017-01-01

    The unique optical properties possessed by plasmonic noble metal nanostructures in consequence of localized surface plasmon resonance (LSPR) are useful in diverse applications like photovoltaics, sensing, non-linear optics, hydrogen generation, and photocatalytic pollutant degradation. The incorporation of plasmonic metal nanostructures into solar cells provides enhancement in light absorption and scattering cross-section (via LSPR), tunability of light absorption profile especially in the visible region of the solar spectrum, and more efficient charge carrier separation, hence maximizing the photovoltaic efficiency. This review discusses about the recent development of different plasmonic metal nanostructures, mainly based on Au or Ag, and their applications in promising third-generation solar cells such as dye-sensitized solar cells, quantum dot-based solar cells, and perovskite solar cells.

  12. Fabrication of Au- and Ag–SiO{sub 2} inverse opals having both localized surface plasmon resonance and Bragg diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Erola, Markus O.A.; Philip, Anish; Ahmed, Tanzir; Suvanto, Sari; Pakkanen, Tuula T., E-mail: Tuula.Pakkanen@uef.fi

    2015-10-15

    The inverse opal films of SiO{sub 2} containing metal nanoparticles can have both the localized surface plasmon resonance (LSPR) of metal nanoparticles and the Bragg diffraction of inverse opal crystals of SiO{sub 2}, which are very useful properties for applications, such as tunable photonic structures, catalysts and sensors. However, effective processes for fabrication of these films from colloidal particles have rarely been reported. In our study, two methods for preparation of inverse opal films of SiO{sub 2} with three different crystal sizes and containing gold or silver nanoparticles (NPs) via self-assembly using electrostatic interactions and capillary forces are reported. The Bragg diffraction of inverse opal films of SiO{sub 2} in the presence and absence of the template was measured and predicted on the basis of with UV–vis spectroscopy and scanning electron microscopy. The preparation methods used provided good-quality inverse opal SiO{sub 2} films containing highly dispersed, plasmonic AuNPs or AgNPs and having both Bragg diffractions and LSPRs. - Graphical abstract: For syntheses of SiO{sub 2} inverse opals containing Au/Ag nanoparticles two approaches and three template sizes were employed. Self-assembly of template molecules and metal nanoparticles occurred using electrostatic interactions and capillary forces. Both the Bragg diffraction of the photonic crystal and the localized surface plasmon resonance of Au/Ag nanoparticles were detected. - Highlights: • Fabrication methods of silica inverse opals containing metal nanoparticles studied. • Three template sizes used to produce SiO{sub 2} inverse opals with Au/Ag nanoparticles. • PS templates with Au nanoparticles adsorbed used in formation of inverse opals. • Ag particles infiltrated in inverse opals with capillary and electrostatic forces. • Bragg diffractions of IOs and surface plasmon resonances of nanoparticles observed.

  13. Colloidal transparent conducting oxide nanocrystals: A new infrared plasmonic material

    Indian Academy of Sciences (India)

    Bharat Tandon; Aswathi Ashok; Angshuman Nag

    2015-06-01

    Thin films of transparent conducting oxides (TCO) are technologically important for applications as a visible light transparent electrode in a wide variety of optoelectronic devices. In the last few years, researchers started to explore novel size- and shape-dependent properties of TCO, where the crystallite size is ∼10 nm. So far, the localized surface plasmon resonance (LSPR) properties of TCO nanocrystals (NCs) have been found to be the most interesting. TCOs like Sn-doped In2O3, Al-doped ZnO and In-doped CdO NCs, exhibit LSPR band in near- to mid-infrared region. LSPR from a TCO NC exhibits many intrinsic differences with that of a metal NC. Carrier density in a TCO NC can easily be tuned by controlling the dopant concentration, which allows the LSPR band to be tuned over a range of ∼2000 nm (∼0.62 eV) in the near- to mid-infrared region. This review discusses recent advances in the understanding of plasmonic properties of various TCO NCs and highlights the potential applications of such unique plasmonic properties.

  14. Gold Nanoparticle-Quantum Dot Fluorescent Nanohybrid: Application for Localized Surface Plasmon Resonance-induced Molecular Beacon Ultrasensitive DNA Detection

    Science.gov (United States)

    Adegoke, Oluwasesan; Park, Enoch Y.

    2016-11-01

    In biosensor design, localized surface plasmon resonance (LSPR)-induced signal from gold nanoparticle (AuNP)-conjugated reporter can produce highly sensitive nanohybrid systems. In order to retain the physicochemical properties of AuNPs upon conjugation, high colloidal stability in aqueous solution is needed. In this work, the colloidal stability with respect to the zeta potential (ZP) of four negatively charged thiol-functionalized AuNPs, thioglycolic (TGA)-AuNPs, 3-mercaptopropionic acid (MPA)-AuNPs, l-cysteine-AuNPs and l-glutathione (GSH)-AuNPs, and a cationic cyteamine-capped AuNPs was studied at various pHs, ionic strength, and NP concentration. A strong dependence of the ZP charge on the nanoparticle (NP) concentration was observed. High colloidal stability was exhibited between pH 3 and 9 for the negatively charged AuNPs and between pH 3 and 7 for the cationic AuNPs. With respect to the ionic strength, high colloidal stability was exhibited at ≤104 μM for TGA-AuNPs, l-cysteine-AuNPs, and GSH-AuNPs, whereas ≤103 μM is recommended for MPA-AuNPs. For the cationic AuNPs, very low ionic strength of ≤10 μM is recommended due to deprotonation at higher concentration. GSH-AuNPs were thereafter bonded to SiO2-functionalized alloyed CdZnSeS/ZnSe1.0S1.3 quantum dots (SiO2-Qdots) to form a plasmon-enhanced AuNP-SiO2-Qdots fluorescent nanohybrid. The AuNP-SiO2-Qdots conjugate was afterward conjugated to a molecular beacon (MB), thus forming an ultrasensitive LSPR-induced SiO2-Qdots-MB biosensor probe that detected a perfect nucleotide DNA sequence at a concentration as low as 10 fg/mL. The limit of detection was 11 fg/mL (1.4 fM) while the biosensor probe efficiently distinguished between single-base mismatch and noncomplementary sequence target.

  15. 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.

  16. 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.

  17. Plasmonic coupling in single flower-like gold nanoparticle assemblies

    Institute of Scientific and Technical Information of China (English)

    Yi Luo; Lacie Dube; Yadong Zhou; Shengli Zou; Jing Zhao

    2016-01-01

    Localized surface plasmon resonance (LSPR) arises when light interacts with metallic nanoparticles (NPs). When nanoparticles (NPs) assemble together, the plasmon coupling effect between the NPs often leads to new features in the LSPR of the assembled structure. Understanding the plasmon coupling in the complex assemblies will greatly benefit the development of new plasmonic devices. Here we demonstrate the fabrication of a 3D structure using two different sized Au NPs as building blocks. This 3D structure was achieved by manipulating the binding efficiency of ligands linking the NPs, and proper choice of the NP size. The assembled structure is flower-like structure, with one 130 nm Au NP in the center, and several 40 nm Au NPs attaching as“petals”. Single particle dark-field scattering measurements of the individual assemblies were performed, together with electrodynamics simulations. The experimental and theoretical studies show that, the plasmonic coupling lead to broadening of the LSPR and additional peaks, depending on the number and 3D arrangement of the 40 nm NPs around the center 130 nm NP.

  18. Ferroplasmons: Intense Localized Surface Plasmons in Metal-Ferromagnetic Nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Sachan, Ritesh [University of Tennessee, Knoxville (UTK); Malasi, Abhinav [ORNL; Ge, Jingxuan [Materials Science and Engineering Department, University of Tennessee, Knoxville, TN, USA; Yadavali, Sagar P [ORNL; Gangopadhyay, Anup [Washington University, St. Louis; Krishna, Dr. Hare [Washington University, St. Louis; Garcia, Hernando [Southern Illinois University; Duscher, Gerd J M [ORNL; Kalyanaraman, Ramki [University of Tennessee, Knoxville (UTK)

    2014-01-01

    Interaction of photons with matter at length scales far below their wavelengths has given rise to many novel phenomena, including localized surface plasmon resonance (LSPR). However, LSPR with narrow bandwidth (BW) is observed only in a select few noble metals, and ferromagnets are not among them. Here, we report the discovery of LSPR in ferromagnetic Co and CoFe alloy (8% Fe) in contact with Ag in the form of bimetallic nanoparticles prepared by pulsed laser dewetting. These plasmons in metal-erromagnetic nanostructures, or ferroplasmons (FP) for short, are in the visible spectrum with comparable intensity and BW to those of the LSPRs from the Ag regions. This finding was enabled by electron energy-loss mapping across individual nanoparticles in a monochromated scanning transmission electron microscope. The appearance of the FP is likely due to plasmonic interaction between the contacting Ag and Co nanoparticles. Since there is no previous evidence for materials that simultaneously show ferromagnetism and such intense LSPRs, this discovery may lead to the design of improved plasmonic materials and applications. It also demonstrates that materials with interesting plasmonic properties can be synthesized using bimetallic nanostructures in contact with each other.

  19. Plasmonic coupling in single flower-like gold nanoparticle assemblies

    Directory of Open Access Journals (Sweden)

    Yi Luo

    2016-10-01

    Full Text Available Localized surface plasmon resonance (LSPR arises when light interacts with metallic nanoparticles (NPs. When nanoparticles (NPs assemble together, the plasmon coupling effect between the NPs often leads to new features in the LSPR of the assembled structure. Understanding the plasmon coupling in the complex assemblies will greatly benefit the development of new plasmonic devices. Here we demonstrate the fabrication of a 3D structure using two different sized Au NPs as building blocks. This 3D structure was achieved by manipulating the binding efficiency of ligands linking the NPs, and proper choice of the NP size. The assembled structure is flower-like structure, with one 130 nm Au NP in the center, and several 40 nm Au NPs attaching as “petals”. Single particle dark-field scattering measurements of the individual assemblies were performed, together with electrodynamics simulations. The experimental and theoretical studies show that, the plasmonic coupling lead to broadening of the LSPR and additional peaks, depending on the number and 3D arrangement of the 40 nm NPs around the center 130 nm NP.

  20. Label-Free LSPR Detection of Trace Lead(II) Ions in Drinking Water by Synthetic Poly(mPD-co-ASA) Nanoparticles on Gold Nanoislands.

    Science.gov (United States)

    Qiu, Guangyu; Ng, Siu Pang; Liang, Xiongyi; Ding, Ning; Chen, Xiangfeng; Wu, Chi-Man Lawrence

    2017-02-07

    Using self-assembly gold nanoislands (SAM-AuNIs) functionalized by poly(m-phenylenediamine-co-aniline-2-sulfonic acid) (poly(mPD-co-ASA)) copolymer nanoparticles as specific receptors, a highly sensitive localized surface plasmon resonance (LSPR) optochemical sensor is demonstrated for detection of trace lead cation (Pb(II)) in drinking water. The copolymer receptor is optimized in three aspects: (1) mole ratio of mPD:ASA monomers, (2) size of copolymer nanoparticles, and (3) surface density of the copolymer. It is shown that the 95:5 (mPD:ASA mole ratio) copolymer with size less than 100 nm exhibits the best Pb(II)-sensing performance, and the 200 times diluted standard copolymer solution contributes to the most effective functionalization protocol. The resulting poly(mPD-co-ASA)-functionalized LSPR sensor attains the detection limit to 0.011 ppb toward Pb(II) in drinking water, and the linear dynamic range covers 0.011 to 5000 ppb (i.e., 6 orders of magnitude). In addition, the sensing system exhibits robust selectivity to Pb(II) in the presence of other metallic cations as well as common anions. The proposed functional copolymer functionalized on AuNIs is found to provide excellent Pb(II)-sensing performance using simple LSPR instrumentation for rapid drinking-water inspection.

  1. 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...

  2. 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.

  3. Using Monoclonal Antibody to Determine Lead Ions with a Localized Surface Plasmon Resonance Fiber-optic Biosensor

    Directory of Open Access Journals (Sweden)

    Mon-Fu Chung

    2008-01-01

    Full Text Available A novel reflection-based localized surface plasmon resonance (LSPR fiber-optic probe has been developed to determine the heavy metal lead ion concentration. Monoclonal antibody as the detecting probe containing massive amino groups to capture Pb(II-chelate complexes was immobilized onto gold nanoparticle-modified optical fiber (NMAuOF. The optimal immobilizing conditions of monoclonal antibody on to the NMAuOF are 189 μg/mL in pH7.4 PBS for 2 h at 25°C. The absorbability of the functionalized NMAuOF sensor increases to 12.2 % upon changing the Pb(II-EDTA level from 10 to 100 ppb with a detection limit of 0.27 ppb. The sensor retains 92.7 % of its original activity and gives reproducible results after storage in 5% D-( -Trehalose dehydrate solution at 4°C for 35 days. In conclusion, the monoclonal antibody-functionalized NMAuOF sensor shows a promising result for determining the concentration of Pb(II with high sensitivity.

  4. Localized Surface Plasmon Resonance-Mediated Charge Trapping/Detrapping for Core-Shell Nanorod-Based Optical Memory Cells.

    Science.gov (United States)

    Zhou, Li; Han, Su-Ting; Shu, Shiwei; Zhuang, Jiaqing; Yan, Yan; Sun, Qi-Jun; Zhou, Ye; Roy, V A L

    2017-09-19

    For following the trend of miniaturization as per Moore's law, increasing efforts have been made to develop single devices with versatile functionalities for Internet of Things (IoT). In this work, organic optical memory devices with excellent dual optoelectronic functionality including light sensing and data storage have been proposed. The Au@Ag core-shell nanorods (NRs)-based memory device exhibits large memory window up to 19.7 V due to the well-controlled morphology of Au@Ag NRs with optimum size and concentration. Furthermore, since the extinction intensity of Au@Ag NRs gradually enhance with the increase in Ag shell thickness, the phototunable behaviors of memory device were systematically studied by varying the thickness of Ag shell. Multilevel data storage can be achieved with the light assistant. Finally, the simulation results demonstrate that the phototunable memory property is originated from the multimode localized surface plasmon resonance (LSPR) of Au@Ag NRs, which is in consistent with the experimental results. The Au@Ag core-shell NRs-based memories may open up a new strategy toward developing high-performance optoelectronic devices.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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...

  14. 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.

  15. 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.

  16. Screening sensitive nanosensors via the investigation of shape-dependent localized surface plasmon resonance of single Ag nanoparticles

    Science.gov (United States)

    Liu, Yue; Huang, Cheng Zhi

    2013-07-01

    Understanding the localized surface plasmon resonance (LSPR) of differently shaped plasmonic nanoparticles benefits screening and designing highly sensitive single nanoparticle sensors. Herein, in the present work, we systematically investigated the shape-dependent scattering light colours and refractive index (RI) sensitivity of Ag nanoparticles (AgNPs) at the single nanoparticle level using conventional dark-field light scattering microscopy and spectroscopy. AgNPs in various shapes and scattering colourful light were synthesized, and the shape effect on the scattering light colour was determined by the colocalization of the same nanoparticles with dark-field microscopy (DFM) and scanning electron microscopy (SEM). The results showed that the AgNPs that scattered blue, cyan, yellow, and red light are spheres, cubes, triangular bipyramids, and rods, respectively, which enable us to directly recognize the shape of AgNPs through dark-field microscopy instead of electron microscopy. Further studies on investigation of the scattering spectral responses of single AgNPs to their surrounding solvents show that the RI sensitivity of AgNPs of different shapes followed the order of rods > cubes > triangular bipyramids > spheres. Among the commonly studied AgNPs, Ag nanorods have the highest RI sensitivity, which increases as the aspect ratio increases. Then, AgNPs of various shapes were used as single nanoparticle sensors for probing the adsorption of small molecules.Understanding the localized surface plasmon resonance (LSPR) of differently shaped plasmonic nanoparticles benefits screening and designing highly sensitive single nanoparticle sensors. Herein, in the present work, we systematically investigated the shape-dependent scattering light colours and refractive index (RI) sensitivity of Ag nanoparticles (AgNPs) at the single nanoparticle level using conventional dark-field light scattering microscopy and spectroscopy. AgNPs in various shapes and scattering colourful

  17. 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

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  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. Identification of the optimal spectral region for plasmonic and nanoplasmonic sensing.

    Science.gov (United States)

    Otte, Marinus A; Sepúlveda, Borja; Ni, Weihai; Juste, Jorge Pérez; Liz-Marzán, Luis M; Lechuga, Laura M

    2010-01-26

    We present a theoretical and experimental study involving the sensing characteristics of wavelength-interrogated plasmonic sensors based on surface plasmon polaritons (SPP) in planar gold films and on localized surface plasmon resonances (LSPR) of single gold nanorods. The tunability of both sensing platforms allowed us to analyze their bulk and surface sensing characteristics as a function of the plasmon resonance position. We demonstrate that a general figure of merit (FOM), which is equivalent in wavelength and energy scales, can be employed to mutually compare both sensing schemes. Most interestingly, this FOM has revealed a spectral region for which the surface sensitivity performance of both sensor types is optimized, which we attribute to the intrinsic dielectric properties of plasmonic materials. Additionally, in good agreement with theoretical predictions, we experimentally demonstrate that, although the SPP sensor offers a much better bulk sensitivity, the LSPR sensor shows an approximately 15% better performance for surface sensitivity measurements when its FOM is optimized. However, optimization of the substrate refractive index and the accessibility of the relevant molecules to the nanoparticles can lead to a total 3-fold improvement of the FOM in LSPR sensors.

  8. Refractometric sensing using propagating versus localized surface plasmons: a direct comparison.

    Science.gov (United States)

    Svedendahl, Mikael; Chen, Si; Dmitriev, Alexandre; Käll, Mikael

    2009-12-01

    We present a direct experimental comparison between the refractive index sensing capabilities of localized surface plasmon resonances (LSPRs) in gold nanodisks and propagating surface plasmon resonances (SPRs) on 50 nm gold films. The comparison is made using identical experimental conditions, and for the same resonance wavelength, lambda(SP) congruent with 700 nm. Biosensing experiments with biotin-avidin coupling reveal that the two sensing platforms have very similar performance, despite a superior bulk refractive index sensing figure of merit for the SPR sensor. The results demonstrate that LSPR sensing based on simple transmission or reflection measurements is a highly competitive technique compared to the traditional SPR sensor.

  9. Nanostructure shape effects on response of plasmonic aptamer sensors.

    Science.gov (United States)

    Balamurugan, Subramanian; Mayer, Kathryn M; Lee, Seunghyun; Soper, Steven A; Hafner, Jason H; Spivak, David A

    2013-09-01

    A localized surface plasmon resonance (LSPR) sensor surface was fabricated by the deposition of gold nanorods on a glass substrate and subsequent immobilization of the DNA aptamer, which specifically bind to thrombin. This LSPR aptamer sensor showed a response of 6-nm λ(max) shift for protein binding with the detection limit of at least 10 pM, indicating one of the highest sensitivities achieved for thrombin detection by optical extinction LSPR. We also tested the LSPR sensor fabricated using gold bipyramid, which showed higher refractive index sensitivity than the gold nanorods, but the overall response of gold bipyramid sensor appears to be 25% less than that of the gold nanorod substrate, despite the approximately twofold higher refractive index sensitivity. XPS analysis showed that this is due to the low surface density of aptamers on the gold bipyramid compared with gold nanorods. The low surface density of the aptamers on the gold bipyramid surface may be due to the effect of shape of the nanostructure on the kinetics of aptamer monolayer formation. The small size of aptamers relative to other bioreceptors is the key to achieving high sensitivity by biosensors on the basis of LSPR, demonstrated here for protein binding. The generality of aptamer sensors for protein detection using gold nanorod and gold nanobipyramid substrates is anticipated to have a large impact in the important development of sensors toward biomarkers, environmental toxins, and warfare agents.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. Asymmetric split nanorings for Fano induced plasmonic sensor in visible region

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Yao, E-mail: dingyao@cqcet.com [General Education College, Chongqing College of Electronic Engineering, Chongqing 401331 (China); Liao, Zhongwei, E-mail: liaozw@cqu.edu.cn [Soft Matter and Interdisciplinary Research Institute, College of Physics, Chongqing University, Chongqing 401331 (China)

    2015-05-01

    Fano resonance exhibits high sensitivity and promising applications in the field of ultra-sensitive plasmonic sensor. In this work, the Fano lineshape in spectra of gold rectangular split nanorings (RSNRs) is investigated using the finite element method. The simulation results figure out the Fano lineshape could be modulated by the positions of split gap in RSNRs for symmetry breaking, which is explained by the plasmonic hybridization theory. Furthermore, the high order bonding plasmon mode H in absorption spectra exhibits high sensitivity in visible region. Our investigations here are beneficial for the design and application of ultra-sensitive LSPR sensor in visible region.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 局域表面等离子体共振效应气体传感器的研究进展%Research Progress on Localized Surface Plasmon Resonance Gas Sensor

    Institute of Scientific and Technical Information of China (English)

    张玉娟; 张红; 段涛; 崔旭东

    2013-01-01

    贵金属纳米结构的局域表面等离子体共振光学在光催化、光学传感器、表面增强光谱学、太阳能电池等领域具有广阔的应用前景.基于贵金属的局域表面等离子体共振效应传感器的性能主要依赖于贵金属的结构,总结了纳米贵金属粒子性质以及各种结构的制备方法和应用,并展望了未来表面等离子体共振效应传感器的发展趋势.%Localized surface plasmon resonance(LSPR) optics of noble metal is a long studied nanoscale phenomenon of considerable recent interest,owing to pontential application in such field as photocatalysis,optical sensors,surface enhanced spectroscopy,solar cells,which has led to advances in several areas of the science and technology of LSPR.These resonances are strongly dependent on the nature of the material,create sharp spectral absorption and scattering,peaks as well as strong electromagnetic near-field enhancements.The nature of the noble metal nanoparticles and the preparation method,application are reviewed in detail.Finally,the LSPR sensor application in other areas and future works are prospected.

  9. 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...

  10. 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...

  11. 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.

  12. A plasmonic colorimetric strategy for biosensing through enzyme guided growth of silver nanoparticles on gold nanostars.

    Science.gov (United States)

    Guo, Yuehua; Wu, Jie; Li, Jie; Ju, Huangxian

    2016-04-15

    A plasmonic colorimetric strategy was designed for sensitive detection of biomolecules through enzyme guided silver nanoparticles (AgNPs) growth on gold nanostars (AuNS). The growth of AgNPs on AuNS led to a substantial blue shift of the localized surface plasmon resonance (LSPR) peak and the color change of AuNS from blue to dark blue, purple and ultimately orange. Both the LSPR blueshift wavelength and the color of detection solution containing AuNS, Ag(+) and ascorbic acid 2-phosphate (AAP) depend on the amount of enzyme that catalyzed the dephosphorylation of AAP to reduce Ag(+) on AuNS surface. Thus this strategy could be used for LSPR and naked-eye detections of both the enzyme such as alkaline phosphatase (ALP) and other biomolecules involved in biorecognition events using ALP as a tag. The LSPR detection method for ALP showed a linear range from 1.0 pM to 25 nM with a detection limit of 0.5 pM. Using DNA as a mode target molecule, this technique showed a detection range from 10 fM to 50 pM DNA with a detection limit of 2.6 fM through the convenient combination with hybridization chain reaction amplification. The proposed plasmonic colorimetric strategy could be extended as a general analytical platform for design of immunosensors and aptasensors with ALP as a label.

  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. 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.

  15. 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.

  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. Localized surface plasmon resonance nanosensing of C-reactive protein with poly(2-methacryloyloxyethyl phosphorylcholine)-grafted gold nanoparticles prepared by surface-initiated atom transfer radical polymerization.

    Science.gov (United States)

    Kitayama, Yukiya; Takeuchi, Toshifumi

    2014-06-03

    Highly sensitive and selective protein nanosensing based on localized surface plasmon resonance (LSPR) of gold nanoparticles (AuNPs) on which polymerized specific ligands were grafted as an artificial protein recognition layer for the target protein were demonstrated. As a model, optical nanosensing for C-reactive protein (CRP), a known biomarker for chronic inflammation that predicts the risk of arteriosclerosis or heart attacks, was achieved by measuring the shift of LSPR spectra derived from the change of permittivity of poly(2-methacryloyloxyethyl phosphorylcholine)-grafted AuNPs (PMPC-g-AuNPs) upon interacting with CRP, in which the PMPC-g-AuNPs layer were grafted on AuNPs by surface-initiated atom transfer radical polymerization (ATRP). This nanosensing system was effective even for detecting CRP concentrations in a human serum solution diluted to 1% (w/w), at which point a limit of detection was ~50 ng/mL and nonspecific adsorption of other proteins was negligible. The nanosensing system using specific ligand-grafted AuNPs has several strengths, such as low preparation cost, avoiding the need for expensive instruments, no necessary complex pretreatments, and high stability, because it does not contain biobased molecules. We believe this novel synthetic route for protein nanosensors, composed of AuNPs and a polymerized specific ligand utilizing surface-initiated controlled/living radical polymerization, will provide a foundation for the design and synthesis of nanosensors targeting various other biomarker proteins, paving the way for future advances in the field of biosensing.

  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. 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.

  2. Tunable Au-Ag nanobowl arrays for size-selective plasmonic biosensing.

    Science.gov (United States)

    Jana, Debrina; Lehnhoff, Emily; Bruzas, Ian; Robinson, Jendai; Lum, William; Sagle, Laura

    2016-08-01

    Selectivity is often a major obstacle for localized surface plasmon resonance-based biosensing in complex biological solutions. An additional degree of selectivity can be achieved through the incorporation of shape complementarity on the nanoparticle surface. Here, we report the versatile fabrication of substrate-bound Au-Ag nanobowl arrays through the galvanic ion replacement of silver nanodisk arrays. Both localized surface plasmon resonance (LSPR) and surface enhanced Raman spectroscopy (SERS) were carried out to detect the binding of analytes of varying size to the nanobowl arrays. Large increases in the LSPR and SERS response were measured for analytes that were small enough to enter the nanobowls, compared to those too large to come into contact with the interior of the nanobowls. This size-selective sensing should prove useful in both size determination and differentiation of large analytes in biological solutions, such as viruses, fungi, and bacterial cells.

  3. Nanometric control of the distance between plasmonic nanoparticles using optical forces.

    Science.gov (United States)

    Sepúlveda, B; Alegret, J; Käll, M

    2007-10-29

    We theoretically analyze the optical forces between two nearby silver nanoparticles for the case when the wavelength of the incoming light is close to the localized surface plasmon resonance (LSPR). It is shown that the optical force between the nanoparticles is enhanced by the LSPR and that it changes from attractive to repulsive for wavelengths slightly shorter than the resonance when the polarization of the incident light is parallel to the axis of the dimer. This behavior can be utilized to generate a stable separation distance between the nanoparticles. In the Rayleigh limit, the equilibrium distance is uniquely determined by the real part of the particle polarizability and the wavelength of the incident light. The results suggest that near-field optical forces can be used to manipulate and organize plasmonic nanoparticles with a tunable spatial resolution in the nanometer regime.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. Formation of one-dimensional Ag-Au solid solution colloids with Au nanorods as seeds, their alloying mechanisms, and surface plasmon resonances

    Science.gov (United States)

    Guo, Tao; Tan, Yiwei

    2012-12-01

    In this work, one dimensional (1D) Ag-Au solid solution nanoalloys were synthesized by rapidly diffusing Ag into the preformed Au nanorod (AuNR) seeds at ambient temperature in aqueous solution. By varying the molar ratio of AgCl/AuNR (in gold atoms), two kinds of 1D Ag-Au alloy nanostructures with a narrow size distribution--AgAu nanowires and Ag33Au67 nanorods--could be obtained in high yields when NaCl and polyvinylpyrrolidone (PVP) were used as an additive and capping reagent, respectively. Based on HRTEM imaging combined with a series of control experiments, it is conceivable that vacancy/defect-motivated interdiffusion of Ag and Au atoms coupled with oxidative etching is a crucial stage in the mechanism responsible for this room-temperature alloying process, and the subsequent conjugation of the fused Ag-Au alloyed nanostructures is associated with the formation of the AgAu nanowires. The resulting 1D Ag-Au nanoalloys form stable colloidal dispersions and show unique localized surface plasmon resonance (LSPR) peaks in the ensemble extinction spectra.In this work, one dimensional (1D) Ag-Au solid solution nanoalloys were synthesized by rapidly diffusing Ag into the preformed Au nanorod (AuNR) seeds at ambient temperature in aqueous solution. By varying the molar ratio of AgCl/AuNR (in gold atoms), two kinds of 1D Ag-Au alloy nanostructures with a narrow size distribution--AgAu nanowires and Ag33Au67 nanorods--could be obtained in high yields when NaCl and polyvinylpyrrolidone (PVP) were used as an additive and capping reagent, respectively. Based on HRTEM imaging combined with a series of control experiments, it is conceivable that vacancy/defect-motivated interdiffusion of Ag and Au atoms coupled with oxidative etching is a crucial stage in the mechanism responsible for this room-temperature alloying process, and the subsequent conjugation of the fused Ag-Au alloyed nanostructures is associated with the formation of the AgAu nanowires. The resulting 1D Ag

  9. Visualizing the size, shape, morphology, and localized surface plasmon resonance of individual gold nanoshells by near-infrared multispectral imaging microscopy.

    Science.gov (United States)

    Mejac, Irena; Bryan, William W; Lee, T Randall; Tran, Chieu D

    2009-08-15

    We have successfully utilized the newly developed near-infrared multispectral imaging (NIR-MSI) microscope to observe and measure directly the localized surface plasmon absorption (LSPR) of individual gold nanoshells. The NIR-MSI is suited for this task because it can simultaneously record spectral and spatial information of a sample with high sensitivity (single pixel resolution) and high spatial resolution (approximately 0.9 microm/pixel). Importantly, the LSPR of individual nanoshells measured by the NIR-MSI microscope agrees well with the spectra calculated theoretically using Mie scattering for the nanoshells (i.e., nanoshells with silica cores approximately 800 nm in diameter and gold shell thicknesses of approximately 35 nm). Additionally, the NIR-MSI microscope enables measurement of LSPR at different positions within a single nanoshell. LSPR spectra were found to be distinct at various positions within a single nanoshell. Since LSPR spectra are known to depend on the shape and morphology of the nanoshells, these results seem to suggest that the individual nanoshells are not smooth and well-defined, but are rather rough and inhomogeneous. The LSPR spectra of single nanoshells in several different solvents were also examined using NIR-MSI and were found to depend on the dielectric constant of the medium. However, the relationship was discovered to be more complex than simply following the Drude equation. Specifically, when (lambda(max)/fwhm)(2) values of LSPR for single gold nanoshells were plotted as a function of 2n(2) (or 2epsilon) for nanoshells in six different solvents, a linear relationship was found for only three solvents: D(2)O, acetonitrile-d(3), and ethyl acetate. Acetone-d(6) showed a slight deviation, whereas formamide and pyridine-d(5) exhibited distinctly different correlations.

  10. 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

  11. Shift of localized surface plasmon resonance by Ar-ion irradiation of Ag–Au bimetallic films deposited on Al{sub 2}O{sub 3} single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Xuan [Graduate School of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628 (Japan); Shibayama, Tamaki, E-mail: shiba@qe.eng.hokudai.ac.jp [Center for Advanced Research of Energy and Materials, Faculty of Engineering, Hokkaido University, Kita-13, Nishi-8, Kita-ku, Sapporo, Hokkaido 060-8628 (Japan); Yu, Ruixuan; Takayanagi, Shinya [Graduate School of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628 (Japan); Watanabe, Seiichi [Center for Advanced Research of Energy and Materials, Faculty of Engineering, Hokkaido University, Kita-13, Nishi-8, Kita-ku, Sapporo, Hokkaido 060-8628 (Japan)

    2013-11-01

    Effects of Ar-ion induced surface nanostructuring were studied using 100 keV Ar-ion irradiation of 30 nm Ag–Au bimetallic films deposited on Al{sub 2}O{sub 3} single crystals, under irradiation fluences ranging from 5.0 × 10{sup 15} cm{sup −2} to 6.3 × 10{sup 16} cm{sup −2}. Scanning electron microscope was used to study the ion-beam-induced surface nanostructuring. As the irradiation fluence increased, dewetting of the bimetallic films on the Al{sub 2}O{sub 3} substrate was observed, and formation of isolated Ag–Au nanostructures sustained on the substrate were obtained. Next, thermal annealing was performed under high vacuum at 1073 K for 2 h; a layer of photosensitive Ag–Au alloy nanoballs partially embedded in the Al{sub 2}O{sub 3} substrate was obtained when higher fluence irradiation (>3.8 × 10{sup 16} cm{sup −2}) was used. The microstructures of the nanoballs were investigated using a transmission electron microscope, and the nanoballs were found to be single crystals with a FCC structure. In addition, photoabsorption spectra were measured, and localized surface plasmon resonance peaks were observed. With increase in the irradiation fluence, the size of the Ag–Au nanoballs on the substrate decreased, and a blue-shift of the LSPR peaks was observed. Further control of the LSPR frequency over a wide range was achieved by modifying the chemical components, and a red-shift of the LSPR peaks was observed as the Au concentration increased. In summary, ion irradiation is an effective approach toward surface nanostructuring, and the nanocomposites obtained have potential applications in optical devices.

  12. 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.

  13. Extracellular Electron Transfer from Aerobic Bacteria to Au-Loaded TiO2 Semiconductor without Light: A New Bacteria-Killing Mechanism Other than Localized Surface Plasmon Resonance or Microbial Fuel Cells.

    Science.gov (United States)

    Wang, Guomin; Feng, Hongqing; Gao, Ang; Hao, Qi; Jin, Weihong; Peng, Xiang; Li, Wan; Wu, Guosong; Chu, Paul K

    2016-09-21

    Titania loaded with noble metal nanoparticles exhibits enhanced photocatalytic killing of bacteria under light illumination due to the localized surface plasmon resonance (LSPR) property. It has been shown recently that loading with Au or Ag can also endow TiO2 with the antibacterial ability in the absence of light. In this work, the antibacterial mechanism of Au-loaded TiO2 nanotubes (Au@TiO2-NT) in the dark environment is studied, and a novel type of extracellular electron transfer (EET) between the bacteria and the surface of the materials is observed to cause bacteria death. Although the EET-induced bacteria current is similar to the LSPR-related photocurrent, the former takes place without light, and no reactive oxygen species (ROS) are produced during the process. The EET is also different from that commonly attributed to microbial fuel cells (MFC) because it is dominated mainly by the materials' surface, but not the bacteria, and the environment is aerobic. EET on the Au@TiO2-NT surface kills Staphylococcus aureus, but if it is combined with special MFC bacteria, the efficiency of MFC may be improved significantly.

  14. Multimodal plasmonic biosensing nanostructures prepared by DNA-directed immobilization of multifunctional DNA-gold nanoparticles.

    Science.gov (United States)

    Tort, Nuria; Salvador, J-Pablo; Marco, M-Pilar

    2017-04-15

    Biofunctional multimodal plasmonic nanostructures suitable for multiplexed localized surface plasmon resonance (LSPR) biosensing have been created by DNA-directed immobilization (DDI) of two distinct multifunctional biohybrid gold nanoparticles. Gold nanoparticles (AuNP) of distinct sizes, and therefore showing distinct plasmon resonant peaks (RP), have been biofunctionalized and codified with two different single stranded-DNA (ssDNA) chains. One of these oligonucleotide chains has been specifically designed to direct each AuNP to a distinct location of the surface of a DNA microarray chip through specific hybridization with complementary oligonucleotide strands. Scanning Electron Microscopy (SEM) has been used to demonstrate selective immobilization of each AuNP on distinct spots. The second ssDNA chain of the AuNPs provides the possibility to introduce by hybridization distinct types of bioactive molecules or bioreceptors, on a reversible manner. In this work, hapten-oligonucleotide bioconjugate probes, with sequences complementary to the second ssDNA linked to the AuNP, have been synthesized and used to create multiplexed hapten-biofuncionalized plasmonic nanostructures. The oligonucleotide probes consist on anabolic androgenic steroid haptens (AAS) covalently linked to specifically designed oligonucleotide sequences. The biofunctionality of these plasmonic nanostructures has been demonstrated by fluorescent microarray immunoassay and LSPR measurements, recording the shift of the RP produced after the antibody binding to the corresponding hapten-oligonucleotide probes immobilized on the nanostructured surface. Preliminary data show that this approach could allow manufacturing multifunctional multimodal LSPR chips for multiplexed analysis of different substances reaching very good detectability. Thus, small molecular weigh, analytes such as stanozolol (ST,) could be detected at concentrations in the low nM range. The results here presented open the door for an

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 银包覆PMMA纳米核壳颗粒的局域表面等离激元共振行为的模拟计算%Simulation on Localized Surface Plasmon Resonance Behaviors of Nanosized PMMA/Ag Core-Shell Structure

    Institute of Scientific and Technical Information of China (English)

    李强; 王连洲; 逯高清; 黄娆; 朱贤方

    2011-01-01

    应用米氏理论,对银膜包覆PMMA纳米核壳结构的局域表面等离激元共振行为进行了模拟计算,研究了颗粒尺寸、核壳比等参数对纳米核壳结构局域表面等离激元共振消光光谱的影响;同时将其与实心银纳米球的局域表面等离激元共振光谱行为进行了比较.结果表明,相对于实心银纳米球,银膜包覆PMMA纳米核壳结构的共振峰位更加红移,且共振峰的宽度更窄.这些性能上的提高,是由于纳米PMMA介质核的存在减弱了电子云振荡过程中的滞后效应,利于化学生物传感器方面的应用.%Localized surface plasmon resonance (LSPR) spectrum behaviors of PMMA/Ag core-shell nanoparticles are extensively and systematically simulated by a calculation method based on Mie theory. Through the simulation calculation, the dependence of the LSPR behaviors of the core-shell nanoparticle on nanoparticle stee, ratio of the radius of PMMA core to the thickness of Ag shell, and some other factors is studied. Furthermore, LSPR behaviors of Ag nanoparticles are simulated as well for comparison. The simulation results show that the nanosized PMMA dielectric core can weaken the retardation effects in the process of free electron resonance in the Ag nanoshell. Thus, compared with the LSPR of Ag nanoparticles, the position of the LSPR peak of the PMMA/Ag core-shell nanoparticles has an even more obvious red shift and the width of the LSPR becomes even narrower. Such simulation results indicate that the core-shell nanoparticles would have more advantages over Ag nanoparticles for potential applications of future chemical and biological nanosensors.

  8. 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

  9. The Physics and Applications of a 3D Plasmonic Nanostructure

    Science.gov (United States)

    Terranova, Brandon B.

    In this work, the dynamics of electromagnetic field interactions with free electrons in a 3D metallic nanostructure is evaluated theoretically. This dissertation starts by reviewing the relevant fundamentals of plasmonics and modern applications of plasmonic systems. Then, motivated by the need to have a simpler way of understanding the surface charge dynamics on complex plasmonic nanostructures, a new plasmon hybridization tree method is introduced. This method provides the plasmonicist with an intuitive way to determine the response of free electrons to incident light in complex nanostructures within the electrostatic regime. Next, a novel 3D plasmonic nanostructure utilizing reflective plasmonic coupling is designed to perform biosensing and plasmonic tweezing applications. By applying analytical and numerical methods, the effectiveness of this nanostructure at performing these applications is determined from the plasmonic response of the nanostructure to an excitation beam of coherent light. During this analysis, it was discovered that under certain conditions, this 3D nanostructure exhibits a plasmonic Fano resonance resulting from the interference of an in-plane dark mode and an out-of-plane bright mode. In evaluating this nanostructure for sensing changes in the local dielectric environment, a figure of merit of 68 is calculated, which is competitive with current localized surface plasmon resonance refractometric sensors. By evaluating the Maxwell stress tensor on a test particle in the vicinity of the nanostructure, it was found that under the right conditions, this plasmonic nanostructure design is capable of imparting forces greater than 10.5 nN on dielectric objects of nanoscale dimensions. The results obtained in these studies provides new routes to the design and engineering of 3D plasmonic nanostructures and Fano resonances in these systems. In addition, the nanostructure presented in this work and the design principles it utilizes have shown

  10. 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.

  11. 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...

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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...

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. Controlled in situ nanoscale enhancement of gold nanowire arrays with plasmonics

    Energy Technology Data Exchange (ETDEWEB)

    MacKenzie, Robert; Fraschina, Corrado; Sannomiya, Takumi; Voeroes, Janos, E-mail: janos.voros@biomed.ee.ethz.ch [Laboratory of Biosensors and Bioelectronics, ETH Zurich, Gloriastrasse 35, 8092 Zurich (Switzerland)

    2011-02-04

    The controlled in situ growth of ordered gold nanoparticles and nanowire arrays has been studied by optically tracking changes in the local surface plasmon resonance (LSPR) spectrum. A spectrometer and custom-programmed analysis software track changes in the LSPR spectrum. The peak position, peak height (i.e. extinction intensity) and peak width (e.g. radius of curvature) were tracked over time to quantify the dynamic growth of gold as soon as the system was exposed to a commercial gold enhancement solution. This enables the controlled dynamic growth of nano-objects without the necessity of characterizing the growth and aggregation kinetics of the gold enhancement solution. The result was the successful enhancement of their electrically conductive and plasmonic properties, as well as the controlled growth and transformation of line-patterned nanoparticles into conductive particle-based nanowires.

  4. Exploring plasmonic coupling in hole-cap arrays

    Directory of Open Access Journals (Sweden)

    Thomas M. Schmidt

    2015-01-01

    Full Text Available The plasmonic coupling between gold caps and holes in thin films was investigated experimentally and through finite-difference time-domain (FDTD calculations. Sparse colloidal lithography combined with a novel thermal treatment was used to control the vertical spacing between caps and hole arrays and compared to separated arrays of holes or caps. Optical spectroscopy and FDTD simulations reveal strong coupling between the gold caps and both Bloch Wave-surface plasmon polariton (BW-SPP modes and localized surface plasmon resonance (LSPR-type resonances in hole arrays when they are in close proximity. The interesting and complex coupling between caps and hole arrays reveals the details of the field distribution for these simple to fabricate structures.

  5. 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.

  6. 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.

  7. 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.

  8. Extended short-wavelength spectral response of organic/(silver nanoparticles/Si nanoholes nanocomposite films) hybrid solar cells due to localized surface plasmon resonance

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zhixin [National Laboratory of Solid State Microstructures and Jiangsu Provincial Key Laboratory of Photonic and Electronic Materials Sciences and Technology, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China); Xu, Ling, E-mail: xuling@nju.edu.cn [National Laboratory of Solid State Microstructures and Jiangsu Provincial Key Laboratory of Photonic and Electronic Materials Sciences and Technology, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China); Zhang, Wengping; Ge, Zhaoyun; Xu, Jun [National Laboratory of Solid State Microstructures and Jiangsu Provincial Key Laboratory of Photonic and Electronic Materials Sciences and Technology, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China); Su, Weining; Yu, Yao [National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093 (China); Ma, Zhongyuan; Chen, Kunji [National Laboratory of Solid State Microstructures and Jiangsu Provincial Key Laboratory of Photonic and Electronic Materials Sciences and Technology, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China)

    2015-04-15

    Highlights: • The silver nanoparticles (AgNPs)/Si nanoholes (SiNHs) nanocomposite films were fabricated. • An enhancement of total absorption in the AgNPs/SiNHs nanocomposite films at the short wavelength was exhibited. • Prototype solar cell device with AgNPs exhibits an increase of the power conversion efficiency by a factor of 2–3. - Abstract: In this letter, we investigated spectral and opto-electronic conversion properties of the inorganic/organic hybrid cells by using silver nanoparticles (AgNPs)/Si nanoholes (SiNHs) nanocomposite films, which were fabricated by the modified metal-assisted electroless etching (EE) method. It was found that the optical absorption spectra of the films with AgNPs demonstrate a clear peak and show the enhancement of total absorption at the short wavelength. The results of current–voltage (I–V) measurements show that solar cells with AgNPs exhibit an increase of the power conversion efficiency by a factor of 2–3, in comparison with those of the samples without AgNPs. Moreover, higher external quantum efficiency (EQE) values in AgNPs-decorated solar cells were confirmed in the short-wavelength spectral region (400–700 nm), which were essential to achieve high-performance photovoltaic cells. We thought these were mainly attributed to the localized surface plasmon resonance (LSPR) effects and increased light scattering of AgNPs.

  9. Enhanced spectrophotometric detection of Hg in water samples by surface plasmon resonance of Au nanoparticles after preconcentration with vortex-assisted liquid-liquid microextraction

    Science.gov (United States)

    Martinis, Estefanía M.; Wuilloud, Rodolfo G.

    2016-10-01

    This article presents an efficient, simple, and cost-effective method for the determination of trace amounts of Hg by vortex-assisted liquid-liquid microextraction (VALLME) coupled to microvolume UV-Vis spectrophotometry. This method correlates changes in the intensity of localized surface plasmon resonance (LSPR) of tetraoctylammonium bromide (TOABr) coated Au nanoparticles (NPs) after interaction with Hg2+ ion. Spectroscopic measurements of the TOABr-coated Au NPs phase with particular absorption properties (strong and well-defined absorption bands) after analyte extraction by VALLME, provide an accurate and sensitive determination of Hg in water samples, comparable with measurements obtained by atomic absorption spectrometry (AAS). Different variables including sample volume, extraction time, and TOABr-coated Au NPs dispersion volume were carefully studied; final experimental conditions were 5 mL, 120 μL and 5 min respectively. The limit of detection (LOD) was 0.8 ng mL- 1. The calibration curve was linear at concentrations between the limit of quantification (LOQ) (4.9 ng mL- 1) and up to at least 120 ng mL- 1 of Hg. The relative standard deviation for six replicate determinations of 20 ng mL- 1 of Hg was 4.7%. This method exhibited an excellent analytical performance in terms of selectivity and sensitivity and it was finally applied for Hg determination in spiked tap and mineral water samples.

  10. 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...

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. Size-Dependent Coherent-Phonon Plasmon Modulation and Deformation Characterization in Gold Bipyramids and Nanojavelins

    Energy Technology Data Exchange (ETDEWEB)

    Kirschner, Matthew S.; Lethiec, Clotilde M.; Lin, Xiao-Min; Schatz, George C.; Chen, Lin X.; Schaller, Richard D.

    2016-05-18

    Localized surface plasmon resonances (LSPRs) arising from metallic nanoparticles offer an array of prospective applications that range from chemical sensing to biotherapies. Bipyramidal particles exhibit particularly narrow ensemble LSPR resonances that reflect small dispersity of size and shape but until recently were only synthetically accessible over a limited range of sizes with corresponding aspect ratios. Narrow size dispersion offers the opportunity to examine ensemble dynamical phenomena such as coherent phonons that induce periodic oscillations of the LSPR energy. Here, we characterize transient optical behavior of a large range of gold bipyramid sizes, as well as higher aspect ratio nanojavelin ensembles with specific attention to the lowest-order acoustic phonon mode of these nanoparticles. We report coherent phonon-driven oscillations of the LSPR position for particles with resonances spanning 670 to 1330 nm. Nanojavelins were shown to behave similarly to bipyramids but offer the prospect of separate control over LSPR energy and coherent phonon oscillation period. We develop a new methodology for quantitatively measuring mechanical expansion caused by photogenerated coherent phonons. Using this method, we find an elongation of approximately 1% per photon absorbed per unit cell and that particle expansion along the lowest frequency acoustic phonon mode is linearly proportional to excitation fluence for the fluence range studied. These characterizations provide insight regarding means to manipulate phonon period and transient mechanical deformation.

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. 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.

  3. 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.

  4. 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...

  5. 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.

  6. 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.

  7. 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...

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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...

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. 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.

  20. 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.

  1. Interferometric and localized surface plasmon based fiber optic sensor

    Science.gov (United States)

    Muri, Harald Ian D. I.; Bano, Andon; Hjelme, Dag Roar

    2017-02-01

    We demonstrate a novel single point, multi-parameter, fiber optic sensor concept based on a combination of interferometric and plasmonic sensor modalities on an optical fiber end face. The sensor consists of a micro-Fabry-Perot interferometer in the form of a hemispherical stimuli-responsive hydrogel with immobilized gold nanoparticles. We present results of proof-of-concept experiments demonstrating local surface plasmon resonance (LSPR) sensing of refractive index (RI) in the visible range and interferometric measurements of volumetric changes of the pH stimuli-responsive hydrogel in near infrared range. The response of LSPR to RI (Δλr/ΔRI 877nm/RI) and the free spectral range (FSR) to pH (ΔpH/ΔFSR = 0.09624/nm) were measured with LSPR relatively constant for hydrogel swelling degree and FSR relatively constant for RI. We expect this novel sensor concept to be of great value for biosensors for medical applications.

  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. 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.

  4. A simple and efficient design to improve the detection of biotin-streptavidin interaction with plasmonic nanobiosensors.

    Science.gov (United States)

    Focsan, Monica; Campu, Andreea; Craciun, Ana-Maria; Potara, Monica; Leordean, Cosmin; Maniu, Dana; Astilean, Simion

    2016-12-15

    In this manuscript we propose a simple and efficient strategy to improve the sensitivity of localized surface plasmon resonance (LSPR) shift-based biosensors using biotin-streptavidin recognition interaction as a proof-of-concept. Specifically, biotin molecules are immobilized on a low-cost plasmonic LSPR biosensor based on annealed self-assembled spherical gold nanoparticles (AuNSs) and successively incubated with increasing concentrations of streptavidin, achieving a limit of detection (LOD) of 5nM. Interestingly, when the detection is performed by the same biotin-functionalized plasmonic AuNSs substrate but against streptavidin previously conjugated to gold nanorods, the LSPR shift is 26-fold enhanced. Moreover, we confirm these results through numerical simulations and demonstrate that the proposed sensing architecture can operate as transducer not only to confirm the adsorption of bioanalyte but also to provide the chemical identity of the capture and targeted molecules from their vibrational Raman fingerprints. Therefore, we are confident that the development of such plasmonic biosensors that use metallic labels for improving the sensitivity of detection could become highly promising for future point-of-care diagnostic assays, pushing sensitivity towards single-molecule detection limit.

  5. 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.

  6. 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.

  7. 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.

  8. 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....

  9. 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...

  10. 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.

  11. 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.

  12. 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.

  13. Plasmonic plano-semi-cylindrical nanocavities with high-efficiency local-field confinement

    Science.gov (United States)

    Liu, Feifei; Zhang, Xinping; Fang, Xiaohui

    2017-01-01

    Plasmonic nanocavity arrays were achieved by producing isolated silver semi-cylindrical nanoshells periodically on a continuous planar gold film. Hybridization between localized surface plasmon resonance (LSPR) in the Ag semi-cylindrical nanoshells (SCNS) and surface plasmon polaritons (SPP) in the gold film was observed as split bonding and anti-bonding resonance modes located at different spectral positions. This led to strong local field enhancement and confinement in the plano-concave nanocavites. Narrow-band optical extinction with an amplitude as high as 1.5 OD, corresponding to 97% reduction in the transmission, was achieved in the visible spectrum. The resonance spectra of this hybrid device can be extended from the visible to the near infrared by adjusting the structural parameters. PMID:28074853

  14. 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.

  15. 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.

  16. 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...

  17. 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.

  18. 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.

  19. 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.

  20. 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...

  1. 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

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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 ...

  7. 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

  8. 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

  9. 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...

  10. 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...

  11. 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

  12. 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

  13. 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

  14. 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...

  15. 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

  16. 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

  17. 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 ...

  18. 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...

  19. 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...

  20. 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.

  1. 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.

  2. 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.

  3. Plasmonic Cu(x)In(y)S2 quantum dots make better photovoltaics than their nonplasmonic counterparts.

    Science.gov (United States)

    Niezgoda, J Scott; Yap, Eugene; Keene, Joseph D; McBride, James R; Rosenthal, Sandra J

    2014-06-11

    A synthetic approach has recently been developed which results in Cu(x)In(y)S2 quantum dots (QDs) possessing localized surface plasmon resonance (LSPR) modes in the near-infrared (NIR) frequencies.1 In this study, we investigate the potential benefits of near-field plasmonic effects centered upon light absorbing nanoparticles in a photovoltaic system by developing and verifying nonplasmonic counterparts as an experimental control. Simple QD-sensitized solar cells (QD-SSCs) were assembled which show an 11.5% relative increase in incident photon conversion efficiency (IPCE) achieved in the plasmon-enhanced devices. We attribute this increase in IPCE to augmented charge excitation stemming from near-field "antenna" effects in the plasmonic Cu(x)In(y)S2 QD-SSCs. This study represents the first of its kind; direct interrogation of the influence of plasmon-on-semiconductor architectures with respect to excitonic absorption in photovoltaic systems.

  4. Plasmonic nanostructures based on block copolymer templates for efficient organic solar cells

    Science.gov (United States)

    Go, Seung Jae; Lee, Dong-Eun; Lee, Dong Hyun; Chin, Byung Doo

    2016-01-01

    Plasmonic nanostructures fabricated from self-assembled patterns of block copolymers (BCPs) were applied for organic solar cells (OSCs). A thin film of a cylinder-forming polystrene- block-poly(2-vinylpyridine) copolymer (PS- b-P2VP) was spin-coated on the transparent electrode of the OSCs, where nanostructures such as dot, dot with mixed line, and line patterns emerged during different solvent annealing processes. Selective conversion of hydrogen tetrachloroaurate (III) (HAuCl4) in P2VP blocks yielded gold (Au) nanostructures, which were used to trigger the localized surface plasmonic resonance (LSPR) effect at the OSCs. Plasmonic nanostructures with almost similar scales of BCP patterns were formed at the anode/buffer interface at the OSC, showing no-table enhancements of the short circuit current ( J sc) and the power conversion efficiency (3.57% for the reference compared to 4.35% for the optimum LSPR-OSC) as the size and the anisotropy of Au patterns changed from a simple dot through an integrated dot-line pattern to a line pattern. Based on the experimental analyses of the light absorption, photoluminescence, and exciton lifetime of OSC, such an enhancement would be mainly attributed to size-dependent LSPR-induced scattering and absorption at the OSC's active layer, which is not in intimate contact with the Au nanostructures. Up to a 26% increase in the power conversion efficiency could be observed at the plasmonic structures from BCP template, providing an accurately tuning and powerful tailoring of the LSPR-enhancing patterns for the OSCs.

  5. 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.

  6. Plasmonic Structural Colors for Plastic Consumer Products

    DEFF Research Database (Denmark)

    Højlund-Nielsen, Emil; Mortensen, N. Asger; Kristensen, Anders

    2014-01-01

    Today colorants, such as pigments or dyes, are used to color plastic-based consumer products, either as base for solid colored bulk polymer or in inks for surface decoration. After usage, the products must be mechanically sorted by color before recycling, limiting any large-scale efficient...... recycling effort. As an alternative to chemistry-based coloring, nano-scale structural coloring has been proposed to reduce the number of materials needed and to increase pattern resolution. Here colors are created by structural based light-matter interactions in the surface. Thereby, the sorting by color...... can be avoided in the recycling state. Plasmon color technology based on aluminum has recently been firmly established as a route towards structural coloring of polymeric materials. We report on the fabrication of colors by localized surface plasmon resonances (LSPR) using roll-to-roll printing...

  7. 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.

  8. 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...

  9. 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.

  10. 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

  11. 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.

  12. 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 ...

  13. 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.

  14. 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...

  15. 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.

  16. 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.

  17. 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.

  18. 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....

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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 ...

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 光纤端面可调LSPR金纳米半球壳阵列的制备%Preparation of Gold Semi-Nanoshell Arrays on Fiber Facet With Controllable LSPR Properties

    Institute of Scientific and Technical Information of China (English)

    张腊梅; 廖艳林; 范群芳; 曹杰; 毛庆和

    2012-01-01

    提出了一种具有可调局域表面等离子体共振(LSPR)特性的光纤端面纳米结构的制备方法.利用二维胶体聚苯乙烯球(PS)单层膜的可转移性,结合溅射沉积,在光纤端面上获得了金纳米阵列结构.扫描电子显微镜和透射电子显微镜图像表明,单个纳米颗粒具有半球壳结构,阵列结构呈现六角密堆积排列;光谱测量结果显示,制备的样品具有明显的LSPR效应,改变溅射时间可实现对LSPR峰位从可见至近红外的调控,且金纳米半球壳直径改变时其LSPR峰位调控规律相似,重复测量结果表明制备的纳米结构具有良好的稳定性.%A fabrication method of gold nanoparticale arrays on optical fiber facet with controllable lo calized surface plasmon resonance (LSPR) properties spectrum was presented in this paper. The gold nan-oparticle arrays on fiber facet were fabricated based on the transferability of polystyrene sphere (PS) colloidal monolayer and the sputtering gold deposition on the PSs. The photos taken by both scanning and transmission electron microscopes show that, the single gold particle has a semi-nanoshell structure, and that the whole nanostructures on the fiber facet are in a hexagonally close-packed arrangement. Spectral analysis indicates that the gold nanoparticles on the fiber facet exhibit a remarkable LSPR effect, and that the LSPR peak location may be effectively controlled to move from the visible to near-infrared region by changing sputtering deposition time. A similar result can be obtained when the diameter of the gold semi-nanoshell is changed. Moreover, the measurement results also show that the LSPR properties of the fabricated nanostructure on fiber facet are very stable.

  13. 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.

  14. Plasmonic Vesicles of Amphiphilic Nanocrystals: Optically Active Multifunctional Platform for Cancer Diagnosis and Therapy.

    Science.gov (United States)

    Song, Jibin; Huang, Peng; Duan, Hongwei; Chen, Xiaoyuan

    2015-09-15

    Vesicular structures with compartmentalized, water-filled cavities, such as liposomes of natural and synthetic amphiphiles, have tremendous potential applications in nanomedicine. When block copolymers self-assemble, the result is polymersomes with tailored structural properties and built-in releasing mechanisms, controlled by stimuli-responsive polymer building blocks. More recently, chemists are becoming interested in multifunctional hybrid vesicles containing inorganic nanocrystals with unique optical, electronic, and magnetic properties. In this Account, we review our recent progress in assembling amphiphilic plasmonic nanostructures to create a new class of multifunctional hybrid vesicles and applying them towards cancer diagnosis and therapy. Localized surface plasmon resonance (LSPR) gives plasmonic nanomaterials a unique set of optical properties that are potentially useful for both biosensing and nanomedicine. For instance, the strong light scattering at their LSPR wavelength opens up the applications of plasmonic nanostructures in single particle plasmonic imaging. Their superior photothermal conversion properties, on the other hand, make them excellent transducers for photothermal ablation and contrast agents for photoacoustic imaging. Of particular note for ultrasensitive detection is that the confined electromagnetic field resulting from excitation of LSPR can give rise to highly efficient surface enhanced Raman scattering (SERS) for molecules in close proximity. We have explored several ways to combine well-defined plasmonic nanocrystals with amphiphilic polymer brushes of diverse chemical functionalities. In multiple systems, we have shown that the polymer grafts impart amphiphilicity-driven self-assembly to the hybrid nanoparticles. This has allowed us to synthesize well-defined vesicles in which we have embedded plasmonic nanocrystals in the shell of collapsed hydrophobic polymers. The hydrophilic brushes extend into external and interior aqueous

  15. 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.

  16. 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.

  17. 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.

  18. 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).

  19. 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.

  20. 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.

  1. 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...

  2. 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.

  3. 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.

  4. Plasmonic Nanostructure for Enhanced Light Absorption in Ultrathin Silicon Solar Cells

    Directory of Open Access Journals (Sweden)

    Jinna He

    2012-01-01

    Full Text Available The performances of thin film solar cells are considerably limited by the low light absorption. Plasmonic nanostructures have been introduced in the thin film solar cells as a possible solution around this issue in recent years. Here, we propose a solar cell design, in which an ultrathin Si film covered by a periodic array of Ag strips is placed on a metallic nanograting substrate. The simulation results demonstrate that the designed structure gives rise to 170% light absorption enhancement over the full solar spectrum with respect to the bared Si thin film. The excited multiple resonant modes, including optical waveguide modes within the Si layer, localized surface plasmon resonance (LSPR of Ag stripes, and surface plasmon polaritons (SPP arising from the bottom grating, and the coupling effect between LSPR and SPP modes through an optimization of the array periods are considered to contribute to the significant absorption enhancement. This plasmonic solar cell design paves a promising way to increase light absorption for thin film solar cell applications.

  5. HSI colour-coded analysis of scattered light of single plasmonic nanoparticles

    Science.gov (United States)

    Zhou, Jun; Lei, Gang; Zheng, Lin Ling; Gao, Peng Fei; Huang, Cheng Zhi

    2016-06-01

    Single plasmonic nanoparticles (PNPs) analysis with dark-field microscopic imaging (iDFM) has attracted much attention in recent years. The ability for quantitative analysis of iDFM is critical, but cumbersome, for characterizing and analyzing the scattered light of single PNPs. Here, a simple automatic HSI colour coding method is established for coding dark-field microscopic (DFM) images of single PNPs with localized surface plasmon resonance (LSPR) scattered light, showing that hue value in the HSI system can realize accurate quantitative analysis of iDFM and providing a novel approach for quantitative chemical and biochemical imaging at the single nanoparticle level.Single plasmonic nanoparticles (PNPs) analysis with dark-field microscopic imaging (iDFM) has attracted much attention in recent years. The ability for quantitative analysis of iDFM is critical, but cumbersome, for characterizing and analyzing the scattered light of single PNPs. Here, a simple automatic HSI colour coding method is established for coding dark-field microscopic (DFM) images of single PNPs with localized surface plasmon resonance (LSPR) scattered light, showing that hue value in the HSI system can realize accurate quantitative analysis of iDFM and providing a novel approach for quantitative chemical and biochemical imaging at the single nanoparticle level. Electronic supplementary information (ESI) available: Experimental section and additional figures. See DOI: 10.1039/c6nr01089j

  6. 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 ...

  7. 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.

  8. Development of silver/gold nanocages onto indium tin oxide glass as a reagentless plasmonic mercury sensor

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Daodan; Hu, Tingting; Chen, Na [The Key Lab of Health Chemistry and Molecular Diagnosis of Suzhou, College of Chemistry, Chemical Engineering and Material Science, Soochow University, Suzhou 215123 (China); Zhang, Wei, E-mail: zhangwei@cigit.ac.cn [Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714 (China); Di, Junwei, E-mail: djw@suda.edu.cn [The Key Lab of Health Chemistry and Molecular Diagnosis of Suzhou, College of Chemistry, Chemical Engineering and Material Science, Soochow University, Suzhou 215123 (China)

    2014-05-01

    Highlights: • A reagentless, sensitive and selective optical sensor for detection of Hg(II) was developed. • Silver–gold nanocages were prepared on the transparent indium tin oxide coated glass surface. • The nanomaterials could act as optical sensing probe as well as reducing agent. • The plasmonic sensor could be used to detect mercury ions in field analysis. Abstract: We demonstrate the utilization of silver/gold nanocages (Ag/Au NCs) deposited onto transparent indium tin oxide (ITO) film glass as the basis of a reagentless, simple and inexpensive mercury probe. The localized surface plasmon resonance (LSPR) peak wavelength was located at ~800 nm. By utilizing the redox reaction between Hg²⁺ ions and Ag atoms that existed in Ag/Au NCs, the LSPR peak of Ag/Au NCs was blue-shifted. Thus, we develop an optical sensing probe for the detection of Hg²⁺ ions. The LSPR peak changes were lineally proportional to the concentration of Hg²⁺ ions over the range from 10 ppb to 0.5 ppm. The detection limit was ~5 ppb. This plasmonic probe shows good selectivity and high sensitivity. The proposed optical probe is successfully applied to the sensing of Hg²⁺ in real samples.

  9. 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.

  10. 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.

  11. 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.

  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. 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.

  14. 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.

  15. 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...

  16. 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.

  17. 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)].

  18. 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.

  19. 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

  20. 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.

  1. 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

  2. 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.

  3. 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.

  4. 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...

  5. 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

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. 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.

  11. 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...

  12. Plasmonic coupling with most of the transition metals: a new family of broad band and near infrared nanoantennas

    Science.gov (United States)

    Manchon, Delphine; Lermé, Jean; Zhang, Taiping; Mosset, Alexis; Jamois, Cécile; Bonnet, Christophe; Rye, Jan-Michael; Belarouci, Ali; Broyer, Michel; Pellarin, Michel; Cottancin, Emmanuel

    2014-12-01

    In this article, we show for the first time, both theoretically and empirically, that plasmonic coupling can be used to generate Localized Surface Plasmon Resonances (LSPRs) in transition metal dimeric nano-antennas (NAs) over a broad spectral range (from the visible to the near infrared) and that the spectral position of the resonance can be controlled through morphological variation of the NAs (size, shape, interparticle distance). First, accurate calculations using the generalized Mie theory on spherical dimers demonstrate that we can take advantage of the plasmonic coupling to enhance LSPRs over a broad spectral range for many transition metals (Pt, Pd, Cr, Ni etc.). The LSPR remains broad for low interparticle distances and masks the various hybridized modes within the overall resonance. However, an analysis of the charge distribution on the surface of the nanoparticles reveals these modes and their respective contributions to the observed LSPR. In the case of spherical dimers, the transfer of the oscillator strengths from the ``dipolar'' mode to higher orders involves a maximum extinction cross-section for intermediate interparticle distances of a few nanometers. The emergence of the LSPR has been then experimentally illustrated with parallelepipedal NAs (monomers and dimers) made of various transition metals (Pt, Pd and Cr) and elaborated by nanolithography. Absolute extinction cross-sections have been measured with the spatial modulation spectroscopy technique over a broad spectral range (300-900 nm) for individual NAs, the morphology of which has been independently characterized by electron microscopy imaging. A clear enhancement of the LSPR has been revealed for a longitudinal excitation and plasmonic coupling has been clearly evidenced in dimers by an induced redshift and broadening of the LSPR compared to monomers. Furthermore, the LSPR has been shown to be highly sensitive to slight modifications of the interparticle distance. All the experimental

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. [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.

  19. 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...

  20. 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.

  1. 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.

  2. 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.

  3. High-Performance LSPR Fiber Sensor Based on Nanometal Rings

    National Research Council Canada - National Science Library

    Yue Jing He

    2014-01-01

    .... It was examined that the current metallic patterns in the fiber sensor can trigger the LSPR by the electric field Er of the core mode HE11, and this is the main reason why this novel fiber sensor can...

  4. 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 ...

  5. 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.

  6. 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.

  7. Boosted photocatalytic efficiency through plasmonic field confinement with bowtie and diabolo nanostructures under LED irradiation.

    Science.gov (United States)

    Lee, Chia-Hua; Liao, Shih-Chieh; Lin, Tzy-Rong; Wang, Shing-Hoa; Lai, Dong-Yan; Chiu, Po-Kai; Lee, Jyh-Wei; Wu, Wen-Fa

    2016-08-08

    Photoresist and electron beam lithography techniques were used to fabricate embedded Ag bowtie and diabolo nanostructures with various apex angles on the surface of a TiO2 film. The reinforced localized surface plasmon resonance (LSPR) and electric field generated at both the Ag/TiO2 and air/TiO2 interfaces enabled high light absorbance in the TiO2 nanostructure. Results for both the bowtie and diabolo nanostructures showed that a reduction in the apex angle enhances both LSPR and Raman intensity. The maximum electric current density observed at the apex indicates that the strongest SPR confines at the tip gap of the bowtie and corners of the diabolo. In a long-wavelength region, as the apex angle increases, the resonant peak wavelength of the standing wave matches the increased length of the prism edges of the bowtie and diabolo to create a redshift. In a short-wavelength region, as the apex angle increases, the blueshift of the resonant peak wavelength is presumably attributable to the increase in the effective index of the local surface plasmon polariton standing wave mainly residing along both the bowtie and diabolo axes. The redshift and blueshift trend in the simulation results for the resonant peak wavelength agrees well with the experimental results. The fastest photocatalytic rate was obtained by placing the Ag/TiO2 bowtie at an apex angle of 30° in the methylene blue solution, revealing that the plasmonic photocatalysis causes the highest degradation efficiency. This is because the Schottky junction and LSPR can stimulate many valid radicals for the environmental improvement.

  8. 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

  9. 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...

  10. 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.

  11. 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.

  12. 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.

  13. Plasmonic silver nanosphere enhanced ZnSe nanoribbon/Si heterojunction optoelectronic devices.

    Science.gov (United States)

    Wang, Li; Chen, Ran; Ren, Zhi-Fei; Ge, Cai-Wang; Liu, Zhen-Xing; He, Shu-Juan; Yu, Yong-Qiang; Wu, Chun-Yan; Luo, Lin-Bao

    2016-05-27

    In this study, we report a localized surface plasmon resonance (LSPR) enhanced optoelectronic device based on a ZnSe:Sb nanoribbon (NR)/Si nano-heterojunction. We experimentally demonstrated that the LSPR peaks of plasmonic Ag nanoparticles (Ag NPs) can be readily tuned by changing their size distribution. Optical analysis reveals that the absorption of ZnSe:Sb NRs was increased after the decoration of the Ag NPs with strong LSPR. Further analysis of the optoelectronic device confirmed the device performance can be promoted: for example, the short-circuit photocurrent density of the ZnSe/Si heterojunction solar cell was improved by 57.6% from 11.75 to 18.52 mA cm(-2) compared to that without Ag NPs. Meanwhile, the responsivity and detectivity of the ZnSe:Sb NRs/Si heterojunction device increased from 117.2 to 184.8 mA W(-1), and from 5.86 × 10(11) to 9.20 × 10(11) cm Hz(1/2) W(-1), respectively.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.