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Sample records for single optical plasmon

  1. Flexible long-range surface plasmon polariton single-mode waveguide for optical interconnects

    DEFF Research Database (Denmark)

    Vernoux, Christian; Chen, Yiting; Markey, Laurent

    2018-01-01

    We present the design, fabrication and characterization of long-range surface plasmon polariton waveguide arrays with materials, mainly silicones, carefully selected with the aim to be used as mechanically flexible single-mode optical interconnections, the socalled "plasmonic arc" working at 1.55μm...

  2. Quantum optics with single nanodiamonds flying over gold films: Towards a Robust quantum plasmonics

    Energy Technology Data Exchange (ETDEWEB)

    Mollet, O.; Drezet, A.; Huant, S. [Institut Néel, CNRS and Université Joseph Fourier, BP 166, F-38042 Grenoble (France)

    2013-12-04

    A nanodiamond (ND) hosting nitrogen-vacancy (NV) color centers is attached on the apex of an optical tip for near-field microscopy. Its fluorescence is used to launch surface plasmon-polaritons (SPPs) in a thin polycrystalline gold film. It is shown that the quantum nature of the initial source of light is preserved after conversion to SPPs. This opens the way to a deterministic quantum plasmonics, where single SPPs can be injected at well-defined positions in a plasmonic device produced by top-down approaches.

  3. Single Nanoparticle Plasmonic Sensors

    Directory of Open Access Journals (Sweden)

    Manish Sriram

    2015-10-01

    Full Text Available The adoption of plasmonic nanomaterials in optical sensors, coupled with the advances in detection techniques, has opened the way for biosensing with single plasmonic particles. Single nanoparticle sensors offer the potential to analyse biochemical interactions at a single-molecule level, thereby allowing us to capture even more information than ensemble measurements. We introduce the concepts behind single nanoparticle sensing and how the localised surface plasmon resonances of these nanoparticles are dependent upon their materials, shape and size. Then we outline the different synthetic approaches, like citrate reduction, seed-mediated and seedless growth, that enable the synthesis of gold and silver nanospheres, nanorods, nanostars, nanoprisms and other nanostructures with tunable sizes. Further, we go into the aspects related to purification and functionalisation of nanoparticles, prior to the fabrication of sensing surfaces. Finally, the recent developments in single nanoparticle detection, spectroscopy and sensing applications are discussed.

  4. Nanoscale and femtosecond optical autocorrelator based on a single plasmonic nanostructure

    International Nuclear Information System (INIS)

    Melentiev, P N; Afanasiev, A E; Balykin, V I; Tausenev, A V; Konyaschenko, A V; Klimov, V V

    2014-01-01

    We demonstrated a nanoscale size, ultrafast and multiorder optical autocorrelator with a single plasmonic nanostructure for measuring the spatio-temporal dynamics of femtosecond laser light. As a nanostructure, we use a split hole resonator (SHR), which was made in an aluminium nanofilm. The Al material yields the fastest response time (100 as). The SHR nanostructure ensures a high nonlinear optical efficiency of the interaction with laser radiation, which leads to (1) the second, (2) the third harmonics generation and (3) the multiphoton luminescence, which, in turn, are used to perform multi-order autocorrelation measurements. The nano-sized SHR makes it possible to conduct autocorrelation measurements (i) with a subwavelength spatial resolution and (ii) with no significant influence on the duration of the laser pulse. The time response realized by the SHR nanostructure is about 10 fs. (letter)

  5. A Variable Single Photon Plasmonic Beamsplitter

    DEFF Research Database (Denmark)

    Israelsen, Niels Møller; Kumar, Shailesh; Huck, Alexander

    Plasmonic structures can both be exploited for scaling down optical components beyond the diffraction limit and enhancing andcollecting the emission from a single dipole emitter. Here, we experimentally demonstrate adiabatic coupling between two silvernanowires using a nitrogen vacancy center as ...

  6. Strong plasmonic enhancement of single molecule photostability in silver dimer optical antennas

    Directory of Open Access Journals (Sweden)

    Kaminska Izabela

    2018-02-01

    Full Text Available Photobleaching is an effect terminating the photon output of fluorophores, limiting the duration of fluorescence-based experiments. Plasmonic nanoparticles (NPs can increase the overall fluorophore photostability through an enhancement of the radiative rate. In this work, we use the DNA origami technique to arrange a single fluorophore in the 12-nm gap of a silver NP dimer and study the number of emitted photons at the single molecule level. Our findings yielded a 30× enhancement in the average number of photons emitted before photobleaching. Numerical simulations are employed to rationalize our results. They reveal the effect of silver oxidation on decreasing the radiative rate enhancement.

  7. Single-Molecule Plasmon Sensing: Current Status and Future Prospects.

    Science.gov (United States)

    Taylor, Adam B; Zijlstra, Peter

    2017-08-25

    Single-molecule detection has long relied on fluorescent labeling with high quantum-yield fluorophores. Plasmon-enhanced detection circumvents the need for labeling by allowing direct optical detection of weakly emitting and completely nonfluorescent species. This review focuses on recent advances in single molecule detection using plasmonic metal nanostructures as a sensing platform, particularly using a single particle-single molecule approach. In the past decade two mechanisms for plasmon-enhanced single-molecule detection have been demonstrated: (1) by plasmonically enhancing the emission of weakly fluorescent biomolecules, or (2) by monitoring shifts of the plasmon resonance induced by single-molecule interactions. We begin with a motivation regarding the importance of single molecule detection, and advantages plasmonic detection offers. We describe both detection mechanisms and discuss challenges and potential solutions. We finalize by highlighting the exciting possibilities in analytical chemistry and medical diagnostics.

  8. Compact plasmonic variable optical attenuator

    DEFF Research Database (Denmark)

    Leosson, Kristjan; Rosenzveig, Tiberiu; Hermannsson, Pétur Gordon

    2008-01-01

    We demonstrate plasmonic nanowire-based thermo-optic variable optical attenuators operating in the 1525-1625 nm wavelength range. The devices have a footprint as low as 1 mm, extinction ratio exceeding 40 dB, driving voltage below 3 V, and full modulation bandwidth of 1 kHz. The polarization...

  9. Harmonics Generation by Surface Plasmon Polaritons on Single Nanowires.

    Science.gov (United States)

    de Hoogh, Anouk; Opheij, Aron; Wulf, Matthias; Rotenberg, Nir; Kuipers, L

    2016-08-17

    We present experimental observations of visible wavelength second- and third-harmonic generation on single plasmonic nanowires of variable widths. We identify that near-infrared surface plasmon polaritons, which are guided along the nanowire, act as the source of the harmonics generation. We discuss the underlying mechanism of this nonlinear process, using a combination of spatially resolved measurements and numerical simulations to show that the visible harmonics are generated via a combination of both local and propagating plasmonic modes. Our results provide the first demonstration of nanoscale nonlinear optics with guided, propagating plasmonic modes on a lithographically defined chip, opening up new routes toward integrated optical circuits for information processing.

  10. Single attosecond pulse generation by using plasmon-driven double optical gating technology in crossed metal nanostructures

    Science.gov (United States)

    Feng, Liqiang; Liu, Katheryn

    2018-05-01

    An effective method to obtain the single attosecond pulses (SAPs) by using the multi-cycle plasmon-driven double optical gating (DOG) technology in the specifically designed metal nanostructures has been proposed and investigated. It is found that with the introduction of the crossed metal nanostructures along the driven and the gating polarization directions, not only the harmonic cutoff can be extended, but also the efficient high-order harmonic generation (HHG) at the very highest orders occurs only at one side of the region inside the nanostructure. As a result, a 93 eV supercontinuum with the near stable phase can be found. Further, by properly introducing an ultraviolet (UV) pulse into the driven laser polarization direction (which is defined as the DOG), the harmonic yield can be enhanced by two orders of magnitude in comparison with the singe polarization gating (PG) technology. However, as the polarized angle or the ellipticity of the UV pulse increase, the enhancement of the harmonic yield is slightly reduced. Finally, by superposing the selected harmonics from the DOG scheme, a 30 as SAP with intensity enhancement of two orders of magnitude can be obtained.

  11. Optimizing the spontaneous-emission ß factor for single optical plasmon generation

    DEFF Research Database (Denmark)

    Chen, Yuntian; Nielsen, Torben Roland; Gregersen, Niels

    2009-01-01

    In applications like quantum cryptography and quantum computation, it is desirable to obtain single photon sources which can produce a train of single photons on demand at a high repetition rate, especially at or near room temperature. Such single-photon sources can be realized by tailoring...

  12. Correlated structure-optical properties studies of plasmonic nanoparticles

    International Nuclear Information System (INIS)

    Ringe, Emilie; Duyne, Richard P Van; Marks, Laurence D

    2014-01-01

    Interest in nanotechnology is driven by unprecedented means to tailor the physical behaviour via structure and composition. Unlike bulk materials, minute changes in size and shape can affect the optical properties of nanoparticles. Characterization, understanding, and prediction of such structure-function relationships is crucial to the development of novel applications such as plasmonic sensors, devices, and drug delivery systems. Such knowledge has been recently vastly expanded through systematic, high throughput correlated measurements, where the localized surface plasmon resonance (LSPR) is probed optically and the particle shape investigated with electron microscopy. This paper will address some of the recent experimental advances in single particle studies that provide new insight not only on the effects of size, composition, and shape on plasmonic properties but also their interrelation. Plasmon resonance frequency and decay, substrate effects, size, shape, and composition will be explored for a variety of plasmonic systems

  13. Optical switches based on surface plasmons

    International Nuclear Information System (INIS)

    Chen Cong; Wang Pei; Yuan Guanghui; Wang Xiaolei; Min Changjun; Deng Yan; Lu Yonghua; Ming Hai

    2008-01-01

    Great attention is being paid to surface plasmons (SPs) because of their potential applications in sensors, data storage and bio-photonics. Recently, more and more optical switches based on surface plasmon effects have been demonstrated either by simulation or experimentally. This article describes the principles, advantages and disadvantages of various types of optical switches based on SPs, in particular the all-optical switches. (authors)

  14. Nonlinear optical model for strip plasmonic waveguides

    DEFF Research Database (Denmark)

    Lysenko, Oleg; Bache, Morten; Lavrinenko, Andrei

    2016-01-01

    This paper presents a theoretical model of nonlinear optical properties for strip plasmonic waveguides. The particular waveguides geometry that we investigate contains a gold core, adhesion layers, and silicon dioxide cladding. It is shown that the third-order susceptibility of the gold core...... significantly depends on the layer thickness and has the dominant contribution to the effective third-order susceptibility of the long-range plasmon polariton mode. This results in two nonlinear optical effects in plasmonic waveguides, which we experimentally observed and reported in [Opt. Lett. 41, 317 (2016...... approaches. (C) 2016 Optical Society of America...

  15. Progress in surface plasmon subwavelength optics

    International Nuclear Information System (INIS)

    Zhang Douguo; Wang Pei; Jiao Xiaojin; Tang Lin; Lu Yonghua; Ming Hai

    2005-01-01

    Now great attention is being paid to the potential applications of surface plasmon polaritons (SPPs) in data storage, light generation, microscopy and bio-photonics. The authors review the properties of SPPs and topics of recent interest in surface plasmon subwavelength optics. (author)

  16. Single-mode surface plasmon distributed feedback lasers.

    Science.gov (United States)

    Karami Keshmarzi, Elham; Tait, R Niall; Berini, Pierre

    2018-03-29

    Single-mode surface plasmon distributed feedback (DFB) lasers are realized in the near infrared using a two-dimensional non-uniform long-range surface plasmon polariton structure. The surface plasmon mode is excited onto a 20 nm-thick, 1 μm-wide metal stripe (Ag or Au) on a silica substrate, where the stripe is stepped in width periodically, forming a 1st order Bragg grating. Optical gain is provided by optically pumping a 450 nm-thick IR-140 doped PMMA layer as the top cladding, which covers the entire length of the Bragg grating, thus creating a DFB laser. Single-mode lasing peaks of very narrow linewidth were observed for Ag and Au DFBs near 882 nm at room temperature. The narrow linewidths are explained by the low spontaneous emission rate into the surface plasmon lasing mode as well as the high quality factor of the DFB structure. The lasing emission is exclusively TM polarized. Kinks in light-light curves accompanied by spectrum narrowing were observed, from which threshold pump power densities can be clearly identified (0.78 MW cm-2 and 1.04 MW cm-2 for Ag and Au DFB lasers, respectively). The Schawlow-Townes linewidth for our Ag and Au DFB lasers is estimated and very narrow linewidths are predicted for the lasers. The lasers are suitable as inexpensive, recyclable and highly coherent sources of surface plasmons, or for integration with other surface plasmon elements of similar structure.

  17. On-Chip Single-Plasmon Nanocircuit Driven by a Self-Assembled Quantum Dot.

    Science.gov (United States)

    Wu, Xiaofei; Jiang, Ping; Razinskas, Gary; Huo, Yongheng; Zhang, Hongyi; Kamp, Martin; Rastelli, Armando; Schmidt, Oliver G; Hecht, Bert; Lindfors, Klas; Lippitz, Markus

    2017-07-12

    Quantum photonics holds great promise for future technologies such as secure communication, quantum computation, quantum simulation, and quantum metrology. An outstanding challenge for quantum photonics is to develop scalable miniature circuits that integrate single-photon sources, linear optical components, and detectors on a chip. Plasmonic nanocircuits will play essential roles in such developments. However, for quantum plasmonic circuits, integration of stable, bright, and narrow-band single photon sources in the structure has so far not been reported. Here we present a plasmonic nanocircuit driven by a self-assembled GaAs quantum dot. Through a planar dielectric-plasmonic hybrid waveguide, the quantum dot efficiently excites narrow-band single plasmons that are guided in a two-wire transmission line until they are converted into single photons by an optical antenna. Our work demonstrates the feasibility of fully on-chip plasmonic nanocircuits for quantum optical applications.

  18. Effective Optical Properties of Plasmonic Nanocomposites

    Directory of Open Access Journals (Sweden)

    Christoph Etrich

    2014-01-01

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

  19. Plasmon-enhanced optically stimulated luminescence

    Energy Technology Data Exchange (ETDEWEB)

    Guidelli, E. J.; Baffa, O. [Universidade de Sao Paulo, Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Departamento de Fisica, Av. Bandeirantes 3900, 14040-901 Ribeirao Preto, Sao Paulo (Brazil); Ramos, A. P., E-mail: ederguidelli@gmail.com [Universidade de Sao Paulo, Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Departamento de Quimica, Av. Bandeirantes 3900, 14040-901 Ribeirao Preto, Sao Paulo (Brazil)

    2015-10-15

    Full text: Optically Stimulated Luminescence dosimeters (OSLD) have been largely used for personal, medical, and industrial radiation dosimetry. Developing highly sensitive and small-sized radiation detectors and dosimeters is essential for improving spatial resolution and consequently diagnosis quality and treatment efficacy in the case of applications in radiodiagnosis and radiation therapy, for instance. Conventional methods to improve the OSLD sensitivity consist of doping and co-doping the host materials with atoms of other elements, thereby increasing the amount of trapping and/or luminescent centers. Our group is researching on the use of the plasmon properties of noble metal nanoparticles to increase OSL intensity. Upon incidence of a light beam with appropriate resonant wavelengths, the oscillation of the free electrons at the nanoparticle surface originates the Localized Surface Plasmons (LSP) and the consequent plasmon resonance band. The interaction between the LSP and the surrounding luminescent material leads to new optical properties largely employed for enhancing several luminescent processes. Here we will show our results regarding the use of LSP to increase OSLD sensitivity. The interaction between the traps/luminescent centers and the plasmons depends on the distance between them, on the plasmon resonance band intensity and position, as well as on the surrounding medium. Therefore, the plasmon-enhanced luminescence is a promising tool to develop more sensitive and miniaturized OSLD. (Author)

  20. Plasmon-enhanced optically stimulated luminescence

    International Nuclear Information System (INIS)

    Guidelli, E. J.; Baffa, O.; Ramos, A. P.

    2015-10-01

    Full text: Optically Stimulated Luminescence dosimeters (OSLD) have been largely used for personal, medical, and industrial radiation dosimetry. Developing highly sensitive and small-sized radiation detectors and dosimeters is essential for improving spatial resolution and consequently diagnosis quality and treatment efficacy in the case of applications in radiodiagnosis and radiation therapy, for instance. Conventional methods to improve the OSLD sensitivity consist of doping and co-doping the host materials with atoms of other elements, thereby increasing the amount of trapping and/or luminescent centers. Our group is researching on the use of the plasmon properties of noble metal nanoparticles to increase OSL intensity. Upon incidence of a light beam with appropriate resonant wavelengths, the oscillation of the free electrons at the nanoparticle surface originates the Localized Surface Plasmons (LSP) and the consequent plasmon resonance band. The interaction between the LSP and the surrounding luminescent material leads to new optical properties largely employed for enhancing several luminescent processes. Here we will show our results regarding the use of LSP to increase OSLD sensitivity. The interaction between the traps/luminescent centers and the plasmons depends on the distance between them, on the plasmon resonance band intensity and position, as well as on the surrounding medium. Therefore, the plasmon-enhanced luminescence is a promising tool to develop more sensitive and miniaturized OSLD. (Author)

  1. Thermal limiting effects in optical plasmonic waveguides

    International Nuclear Information System (INIS)

    Ershov, A.E.; Gerasimov, V.S.; Gavrilyuk, A.P.; Karpov, S.V.; Zakomirnyi, V.I.; Rasskazov, I.L.; Polyutov, S.P.

    2017-01-01

    We have studied thermal effects occurring during excitation of optical plasmonic waveguide (OPW) in the form of linear chain of spherical Ag nanoparticles by pulsed laser radiation. It was shown that heating and subsequent melting of the first irradiated particle in a chain can significantly deteriorate the transmission efficiency of OPW that is the crucial and limiting factor and continuous operation of OPW requires cooling devices. This effect is caused by suppression of particle's surface plasmon resonance due to reaching the melting point temperature. We have determined optimal excitation parameters which do not significantly affect the transmission efficiency of OPW. - Highlights: • The thermodynamic model was developed to study thermal effects at nanoscale. • Developed model considers temperature-dependent permittivity of the nanoparticles. • Thermal effects significantly suppress transmission efficiency of plasmonic chains. • Optimal parameters for stable operation of plasmonic chains were defined.

  2. Plasmonic nanopatch array for optical integrated circuit applications.

    Science.gov (United States)

    Qu, Shi-Wei; Nie, Zai-Ping

    2013-11-08

    Future plasmonic integrated circuits with the capability of extremely high-speed data processing at optical frequencies will be dominated by the efficient optical emission (excitation) from (of) plasmonic waveguides. Towards this goal, plasmonic nanoantennas, currently a hot topic in the field of plasmonics, have potential to bridge the mismatch between the wave vector of free-space photonics and that of the guided plasmonics. To manipulate light at will, plasmonic nanoantenna arrays will definitely be more efficient than isolated nanoantennas. In this article, the concepts of microwave antenna arrays are applied to efficiently convert plasmonic waves in the plasmonic waveguides into free-space optical waves or vice versa. The proposed plasmonic nanoantenna array, with nanopatch antennas and a coupled wedge plasmon waveguide, can also act as an efficient spectrometer to project different wavelengths into different directions, or as a spatial filter to absorb a specific wavelength at a specified incident angle.

  3. Low-frequency active surface plasmon optics on semiconductors

    NARCIS (Netherlands)

    Gómez Rivas, J.; Kuttge, M.; Kurz, H.; Haring Bolivar, P.; Sánchez-Gil, J.A.

    2006-01-01

    A major challenge in the development of surface plasmon optics or plasmonics is the active control of the propagation of surface plasmon polaritons (SPPs). Here, we demonstrate the feasibility of low-frequency active plasmonics using semiconductors. We show experimentally that the Bragg scattering

  4. Coupling single emitters to quantum plasmonic circuits

    DEFF Research Database (Denmark)

    Huck, Alexander; Andersen, Ulrik Lund

    2016-01-01

    In recent years, the controlled coupling of single-photon emitters to propagating surface plasmons has been intensely studied, which is fueled by the prospect of a giant photonic nonlinearity on a nanoscaled platform. In this article, we will review the recent progress on coupling single emitters...

  5. Atomically flat single-crystalline gold nanostructures for plasmonic nanocircuitry

    Energy Technology Data Exchange (ETDEWEB)

    Huang, J S; Geisler, P; Bruening, C; Kern, J; Prangsma, J C; Wu, X; Feichtner, Thorsten; Ziegler, J; Weinmann, P; Kamp, M; Forchel, A; Hecht, B [Wilhelm-Conrad-Roentgen-Center for Complex Material Systems, University of Wuerzburg (Germany); Biagioni, P [CNISM, Dipartimento di Fisica, Politecnico di Milano (Italy)

    2011-07-01

    Deep subwavelength integration of high-definition plasmonic nano-structures is of key importance for the development of future optical nanocircuitry. So far the experimental realization of proposed extended plasmonic networks remains challenging, mainly due to the multi-crystallinity of commonly used thermally evaporated gold layers. Resulting structural imperfections in individual circuit elements drastically reduce the yield of functional integrated nanocircuits. Here we demonstrate the use of very large but thin chemically grown single-crystalline gold flakes. After immobilization on any arbitrary surface, they serve as an ideal basis for focused-ion beam milling. We present high-definition ultra-smooth gold nanostructures with reproducible nanosized features over micrometer lengthscales. By comparing multi- and single-crystalline optical antennas we prove that the latter have superior optical properties which are in good agreement with numerical simulations.

  6. Coherent interaction of single molecules and plasmonic nanowires

    Science.gov (United States)

    Gerhardt, Ilja; Grotz, Bernhard; Siyushev, Petr; Wrachtrup, Jörg

    2017-09-01

    Quantum plasmonics opens the option to integrate complex quantum optical circuitry onto chip scale devices. In the past, often external light sources were used and nonclassical light was coupled in and out of plasmonic structures, such as hole arrays or waveguide structures. Another option to launch single plasmonic excitations is the coupling of single emitters in the direct proximity of, e.g., a silver or gold nanostructure. Here, we present our attempts to integrate the research of single emitters with wet-chemically grown silver nanowires. The emitters of choice are single organic dye molecules under cryogenic conditions, which are known to act as high-brightness and extremely narrow-band single photon sources. Another advantage is their high optical nonlinearity, such that they might mediate photon-photon interactions on the nanoscale. We report on the coupling of a single molecule fluorescence emission through the wire over the length of several wavelengths. The transmission of coherently emitted photons is proven by an extinction type experiment. As for influencing the spectral properties of a single emitter, we are able to show a remote change of the line-width of a single terrylene molecule, which is in close proximity to the nanowire.

  7. Quantum optical properties in plasmonic systems

    Energy Technology Data Exchange (ETDEWEB)

    Ooi, C. H. Raymond [Department of Physics, University of Malaya, 50603, Kuala Lumpur (Malaysia)

    2015-04-24

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

  8. Plasmonic tunnel junctions for single-molecule redox chemistry.

    Science.gov (United States)

    de Nijs, Bart; Benz, Felix; Barrow, Steven J; Sigle, Daniel O; Chikkaraddy, Rohit; Palma, Aniello; Carnegie, Cloudy; Kamp, Marlous; Sundararaman, Ravishankar; Narang, Prineha; Scherman, Oren A; Baumberg, Jeremy J

    2017-10-20

    Nanoparticles attached just above a flat metallic surface can trap optical fields in the nanoscale gap. This enables local spectroscopy of a few molecules within each coupled plasmonic hotspot, with near thousand-fold enhancement of the incident fields. As a result of non-radiative relaxation pathways, the plasmons in such sub-nanometre cavities generate hot charge carriers, which can catalyse chemical reactions or induce redox processes in molecules located within the plasmonic hotspots. Here, surface-enhanced Raman spectroscopy allows us to track these hot-electron-induced chemical reduction processes in a series of different aromatic molecules. We demonstrate that by increasing the tunnelling barrier height and the dephasing strength, a transition from coherent to hopping electron transport occurs, enabling observation of redox processes in real time at the single-molecule level.

  9. Fiber optic particle plasmon resonance sensor based on plasmonic light scattering interrogation

    International Nuclear Information System (INIS)

    Lin, H.Y.; Huang, C.H.; Chau, L.K.

    2012-01-01

    A highly sensitive fiber optic particle plasmon resonance sensor (FO-PPR) is demonstrated for label-free biochemical detection. The sensing strategy relies on interrogating the plasmonic scattering of light from gold nanoparticles on the optical fiber in response to the surrounding refractive index changes or molecular binding events. The refractive index resolution is estimated to be 3.8 x 10 -5 RIU. The limit of detection for anti-DNP antibody spiked in buffer is 1.2 x 10 -9 g/ml (5.3 pM) by using the DNP-functionalized FO-PPR sensor. The image processing of simultaneously recorded plasmonic scattering photographs at different compartments of the sensor is also demonstrated. Results suggest that the compact sensor can perform multiple independent measurements simultaneously by means of monitoring the plasmonic scattering intensity via photodiodes or a CCD. The potential of using a combination of different kinds of noble metal nanoparticles with different types of functionalized probes in multiple cascaded detection windows on a single fiber to become an inexpensive and ultrasensitive linear-array sensing platform for higher-throughput biochemical detection is provided. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. Engineering Gold Nanorod-Based Plasmonic Nanocrystals for Optical Applications

    KAUST Repository

    Huang, Jianfeng

    2015-09-01

    Plasmonic nanocrystals have a unique ability to support localized surface plasmon resonances and exhibit rich and intriguing optical properties. Engineering plasmonic nanocrystals can maximize their potentials for specific applications. In this dissertation, we developed three unprecedented Au nanorod-based plasmonic nanocrystals through rational design of the crystal shape and/or composition, and successfully demonstrated their applications in light condensation, photothermal conversion, and surface-enhanced Raman spectroscopy (SERS). The “Au nanorod-Au nanosphere dimer” nanocrystal was synthesized via the ligand-induced asymmetric growth of a Au nanosphere on a Au nanorod. This dimeric nanostructure features an extraordinary broadband optical absorption in the range of 400‒1400nm, and it proved to be an ideal black-body material for light condensation and an efficient solar-light harvester for photothermal conversion. The “Au nanorod (core) @ AuAg alloy (shell)” nanocrystal was built through the epitaxial growth of homogeneously alloyed AuAg shells on Au nanorods by precisely controlled synthesis. The resulting core-shell structured, bimetallic nanorods integrate the merits of the AuAg alloy with the advantages of anisotropic nanorods, exhibiting strong, stable and tunable surface plasmon resonances that are essential for SERS applications in a corrosive environment. The “high-index faceted Au nanorod (core) @ AuPd alloy (shell)” nanocrystal was produced via site-specific epitaxial growth of AuPd alloyed horns at the ends of Au nanorods. The AuPd alloyed horns are bound with high-index side facets, while the Au nanorod concentrates an intensive electric field at each end. This unique configuration unites highly active catalytic sites with strong SERS sites into a single entity and was demonstrated to be ideal for in situ monitoring of Pd-catalyzed reactions by SERS. The synthetic strategies developed here are promising towards the fabrication of

  11. A nonlinear plasmonic waveguide based all-optical bidirectional switching

    Science.gov (United States)

    Bana, Xiaoqiang; Pang, Xingxing; Li, Xiaohui; Hu, Bin; Guo, Yixuan; Zheng, Hairong

    2018-01-01

    In this paper, an all-optical switching with a nanometer coupled ring resonator is demonstrated based on the nonlinear material. By adjusting the light intensity, we implement the resonance wavelength from 880 nm to 940 nm in the nonlinear material structure monocyclic. In the bidirectional switch structure, the center wavelength (i.e. 880 nm) is fixed. By changing the light intensity from I = 0 to I = 53 . 1 MW /cm2, the function of optical switching can be obtained. The results demonstrate that both the single-ring cavity and the T-shaped double-ring structure can realize the optical switching effect. This work takes advantage of the simple structure. The single-ring cavity plasmonic switches have many advantages, such as nanoscale size, low pumping light intensity, ultrafast response time (femtosecond level), etc. It is expected that the proposed all-optical integrated devices can be potentially applied in optical communication, signal processing, and signal sensing, etc.

  12. All-fiber hybrid photon-plasmon circuits: integrating nanowire plasmonics with fiber optics.

    Science.gov (United States)

    Li, Xiyuan; Li, Wei; Guo, Xin; Lou, Jingyi; Tong, Limin

    2013-07-01

    We demonstrate all-fiber hybrid photon-plasmon circuits by integrating Ag nanowires with optical fibers. Relying on near-field coupling, we realize a photon-to-plasmon conversion efficiency up to 92% in a fiber-based nanowire plasmonic probe. Around optical communication band, we assemble an all-fiber resonator and a Mach-Zehnder interferometer (MZI) with Q-factor of 6 × 10(6) and extinction ratio up to 30 dB, respectively. Using the MZI, we demonstrate fiber-compatible plasmonic sensing with high sensitivity and low optical power.

  13. 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.

  14. Strong reduction of spectral heterogeneity in gold bipyramids for single-particle and single-molecule plasmon sensing.

    Science.gov (United States)

    Peters, S M E; Verheijen, M A; Prins, M W J; Zijlstra, P

    2016-01-15

    Single metal nanoparticles are attractive biomolecular sensors. Binding of analyte to a functional particle results in a plasmon shift that can be conveniently monitored in a far-field optical microscope. Heterogeneities in spectral properties of individual particles in an ensemble affect the reliability of a single-particle plasmon sensor, especially when plasmon shifts are monitored in real-time using a fixed irradiation wavelength. We compare the spectral heterogeneity of different plasmon sensor geometries (gold nanospheres, nanorods, and bipyramids) and correlate this to their size and aspect-ratio dispersion. We show that gold bipyramids exhibit a strongly reduced heterogeneity in aspect ratio and plasmon wavelength compared to commonly used gold nanorods. We show that this translates into a significantly improved homogeneity of the response to molecular binding without compromising single-molecule sensitivity.

  15. 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.

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

    KAUST Repository

    Amin, Muhammad; Farhat, Mohamed; Bagci, Hakan

    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.

  17. Linear and ultrafast nonlinear plasmonics of single nano-objects

    Science.gov (United States)

    Crut, Aurélien; Maioli, Paolo; Vallée, Fabrice; Del Fatti, Natalia

    2017-03-01

    Single-particle optical investigations have greatly improved our understanding of the fundamental properties of nano-objects, avoiding the spurious inhomogeneous effects that affect ensemble experiments. Correlation with high-resolution imaging techniques providing morphological information (e.g. electron microscopy) allows a quantitative interpretation of the optical measurements by means of analytical models and numerical simulations. In this topical review, we first briefly recall the principles underlying some of the most commonly used single-particle optical techniques: near-field, dark-field, spatial modulation and photothermal microscopies/spectroscopies. We then focus on the quantitative investigation of the surface plasmon resonance (SPR) of metallic nano-objects using linear and ultrafast optical techniques. While measured SPR positions and spectral areas are found in good agreement with predictions based on Maxwell’s equations, SPR widths are strongly influenced by quantum confinement (or, from a classical standpoint, surface-induced electron scattering) and, for small nano-objects, cannot be reproduced using the dielectric functions of bulk materials. Linear measurements on single nano-objects (silver nanospheres and gold nanorods) allow a quantification of the size and geometry dependences of these effects in confined metals. Addressing the ultrafast response of an individual nano-object is also a powerful tool to elucidate the physical mechanisms at the origin of their optical nonlinearities, and their electronic, vibrational and thermal relaxation processes. Experimental investigations of the dynamical response of gold nanorods are shown to be quantitatively modeled in terms of modifications of the metal dielectric function enhanced by plasmonic effects. Ultrafast spectroscopy can also be exploited to unveil hidden physical properties of more complex nanosystems. In this context, two-color femtosecond pump-probe experiments performed on individual

  18. Engineering surface plasmon based fiber-optic sensors

    International Nuclear Information System (INIS)

    Dhawan, Anuj; Muth, John F.

    2008-01-01

    Ordered arrays of nanoholes with subwavelength diameters, and submicron array periodicity were fabricated on the tips of gold-coated optical fibers using focused ion beam (FIB) milling. This provided a convenient platform for evaluating extraordinary transmission of light through subwavelength apertures and allowed the implementation of nanostructures for surface plasmon engineered sensors. The fabrication procedure was straightforward and implemented on single mode and multimode optical fibers as well as etched and tapered fiber tips. Control of the periodicity and spacing of the nanoholes allowed the wavelength of operation to be tailored. Large changes in optical transmission were observed at the designed wavelengths, depending on the surrounding refractive index, allowing the devices to be used as fiber-optic sensors

  19. Engineering surface plasmon based fiber-optic sensors

    Energy Technology Data Exchange (ETDEWEB)

    Dhawan, Anuj [Department of Electrical and Computer Engineering, NC State University, Raleigh, NC 27606 (United States); Muth, John F. [Department of Electrical and Computer Engineering, NC State University, Raleigh, NC 27606 (United States)], E-mail: muth@unity.ncsu.edu

    2008-04-15

    Ordered arrays of nanoholes with subwavelength diameters, and submicron array periodicity were fabricated on the tips of gold-coated optical fibers using focused ion beam (FIB) milling. This provided a convenient platform for evaluating extraordinary transmission of light through subwavelength apertures and allowed the implementation of nanostructures for surface plasmon engineered sensors. The fabrication procedure was straightforward and implemented on single mode and multimode optical fibers as well as etched and tapered fiber tips. Control of the periodicity and spacing of the nanoholes allowed the wavelength of operation to be tailored. Large changes in optical transmission were observed at the designed wavelengths, depending on the surrounding refractive index, allowing the devices to be used as fiber-optic sensors.

  20. Nano-fabricated plasmonic optical transformer

    Science.gov (United States)

    Choo, Hyuck; Cabrini, Stefano; Schuck, P. James; Liang, Xiaogan; Yablonovitch, Eli

    2015-06-09

    The present invention provides a plasmonic optical transformer to produce a highly focuses optical beam spot, where the transformer includes a first metal layer, a dielectric layer formed on the first metal layer, and a second metal layer formed on the dielectric layer, where the first metal layer, the dielectric layer, and the second layer are patterned to a shape including a first section having a first cross section, a second section following the first section having a cross-section tapering from the first section to a smaller cross-section, and a third section following the second section having a cross-section matching the tapered smaller cross-section of the second section.

  1. Plasmonics

    DEFF Research Database (Denmark)

    Berini, P.; Bozhevolnyi, Sergey I.; Kim, D. S.

    2016-01-01

    referred to as “extraordinary optical transmission.” Surface plasmons are intimately involved in the response of “metamaterials” and “metasurfaces” constructed from deep subwavelength metallic features, producing esoteric macroscopic properties such as a negative refractive index, or a permittivity...... or localized at metal nanostructures. Light suitable for exciting surface plasmons is typically within or near the visible but may extend into the infrared and ultraviolet regions. Metallic structures that support surface plasmons are highly varied, including planar arrangements of metal films, stripes...

  2. Surface Plasmon Wave Adapter Designed with Transformation Optics

    DEFF Research Database (Denmark)

    Zhang, Jingjing; Xiao, Sanshui; Wubs, Martijn

    2011-01-01

    On the basis of transformation optics, we propose the design of a surface plasmon wave adapter which confines surface plasmon waves on non-uniform metal surfaces and enables adiabatic mode transformation of surface plasmon polaritons with very short tapers. This adapter can be simply achieved...... with homogeneous anisotropic naturally occurring materials or subwavelength grating-structured dielectric materials. Full wave simulations based on a finite-element method have been performed to validate our proposal....

  3. Direct Photonic-Plasmonic Coupling and Routing in Single Nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Rouxue; Pausauskie, Peter; Huang, Jiaxing; Yang, Piedong

    2009-10-20

    Metallic nanoscale structures are capable of supporting surface plasmon polaritons (SPPs), propagating collective electron oscillations with tight spatial confinement at the metal surface. SPPs represent one of the most promising structures to beat the diffraction limit imposed by conventional dielectric optics. Ag nano wires have drawn increasing research attention due to 2D sub-100 nm mode confinement and lower losses as compared with fabricated metal structures. However, rational and versatile integration of Ag nanowires with other active and passive optical components, as well as Ag nanowire based optical routing networks, has yet to be achieved. Here, we demonstrate that SPPs can be excited simply by contacting a silver nanowire with a SnO2 nanoribbon that serves both as an unpolarized light source and a dielectric waveguide. The efficient coupling makes it possible to measure the propagation-distance-dependent waveguide spectra and frequency-dependent propagation length on a single Ag nanowire. Furthermore, we have demonstrated prototypical photonic-plasmonic routing devices, which are essential for incorporating low-loss Ag nanowire waveguides as practical components into high-capacity photonic circuits.

  4. Plasmonic Nanomaterial-Based Optical Biosensing Platforms for Virus Detection

    Directory of Open Access Journals (Sweden)

    Jaewook Lee

    2017-10-01

    Full Text Available Plasmonic nanomaterials (P-NM are receiving attention due to their excellent properties, which include surface-enhanced Raman scattering (SERS, localized surface plasmon resonance (LSPR effects, plasmonic resonance energy transfer (PRET, and magneto optical (MO effects. To obtain such plasmonic properties, many nanomaterials have been developed, including metal nanoparticles (MNP, bimetallic nanoparticles (bMNP, MNP-decorated carbon nanotubes, (MNP-CNT, and MNP-modified graphene (MNP-GRP. These P-NMs may eventually be applied to optical biosensing systems due to their unique properties. Here, probe biomolecules, such as antibodies (Ab, probe DNA, and probe aptamers, were modified on the surface of plasmonic materials by chemical conjugation and thiol chemistry. The optical property change in the plasmonic nanomaterials was monitored based on the interaction between the probe biomolecules and target virus. After bioconjugation, several optical properties, including fluorescence, plasmonic absorbance, and diffraction angle, were changed to detect the target biomolecules. This review describes several P-NMs as potential candidates of optical sensing platforms and introduces various applications in the optical biosensing field.

  5. A plasmonic biosensor with single-molecule sensitivity

    NARCIS (Netherlands)

    Zijlstra, P.; Paulo, P.M.R.; Yuan, H.; Khatua, S.; Yorulmaz, M.; Orrit, M.

    2013-01-01

    The plasmon resonance of a single metal nanoparticle induces an enhancement of the local electromagnetic field. We exploit this field enhancement to detect single molecules that are (1) poorly fluorescent or (2) completely non-fluorescent.

  6. Evanescent waves in optics an introduction to plasmonics

    CERN Document Server

    Bertolotti, Mario; M Guzman, Angela

    2017-01-01

    This monograph provides an introductory discussion of evanescent waves and plasmons, describes their properties and uses, and shows how they are fundamental when operating with nanoscale optics. Far field optics is not suitable for the design, description, and operation of devices at this nanometre scale. Instead one must work with models based on near-field optics and surface evanescent waves. The new discipline of plasmonics has grown to encompass the generation and application of plasmons both as a travelling excitation in a nanostructure and as a stationary enhancement of the electrical field near metal nanosurfaces. The book begins with a brief review of the basic concepts of electromagnetism, then introduces evanescent waves through reflection and refraction, and shows how they appear in diffraction problems, before discussing the role that they play in optical waveguides and sensors. The application of evanescent waves in super-resolution devices is briefly presented, before plasmons are introduced. Th...

  7. Transparent conducting oxides for electro-optical plasmonic modulators

    DEFF Research Database (Denmark)

    Babicheva, Viktoriia; Boltasseva, Alexandra; Lavrinenko, Andrei V.

    2015-01-01

    The ongoing quest for ultra-compact opticaldevices has reached a bottleneck due to the diffractionlimit in conventional photonics. New approaches that providesubwavelength optical elements, and therefore leadto miniaturization of the entire photonic circuit, are urgentlyrequired. Plasmonics, whic...

  8. Quasistatic limit for plasmon-enhanced optical chirality

    Science.gov (United States)

    Finazzi, Marco; Biagioni, Paolo; Celebrano, Michele; Duò, Lamberto

    2015-05-01

    We discuss the possibility of enhancing the chiroptical response from molecules uniformly distributed around nanostructures that sustain localized plasmon resonances. We demonstrate that the average optical chirality in the near field of any plasmonic nanostructure cannot be significantly higher than that in a plane wave. This conclusion stems from the quasistatic nature of the nanoparticle-enhanced electromagnetic fields and from the fact that, at optical frequencies, the magnetic response of matter is much weaker than the electric one.

  9. Tunable enhanced optical absorption of graphene using plasmonic perfect absorbers

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Yijun [Institute of Optoelectronic Technology, Department of Electronic Engineering, Xiamen University, Xiamen 361005 (China); Institute of Electromagnetics and Acoustics, Department of Electronic Science, Xiamen University, Xiamen 361005 (China); Zhu, Jinfeng, E-mail: nanoantenna@hotmail.com [Institute of Electromagnetics and Acoustics, Department of Electronic Science, Xiamen University, Xiamen 361005 (China); Liu, Qing Huo [Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina 27708 (United States)

    2015-01-26

    Enhancement and manipulation of light absorption in graphene is a significant issue for applications of graphene-based optoelectronic devices. In order to achieve this purpose in the visible region, we demonstrate a design of a graphene optical absorber inspired by metal-dielectric-metal metamaterial for perfect absorption of electromagnetic waves. The optical absorbance ratios of single and three atomic layer graphene are enhanced up to 37.5% and 64.8%, respectively. The graphene absorber shows polarization-dependence and tolerates a wide range of incident angles. Furthermore, the peak position and bandwidth of graphene absorption spectra are tunable in a wide wavelength range through a specific structural configuration. These results imply that graphene in combination with plasmonic perfect absorbers have a promising potential for developing advanced nanophotonic devices.

  10. Chiral nanophotonics chiral optical properties of plasmonic systems

    CERN Document Server

    Schäferling, Martin

    2017-01-01

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

  11. Green's tensor calculations of plasmon resonances of single holes and hole pairs in thin gold films

    International Nuclear Information System (INIS)

    Alegret, Joan; Kaell, Mikael; Johansson, Peter

    2008-01-01

    We present numerical calculations of the plasmon properties of single-hole and hole-pair structures in optically thin gold films obtained with the Green's tensor formalism for stratified media. The method can be used to obtain the optical properties of a given hole system, without problems associated with the truncation of the infinite metal film. The calculations are compared with previously published experimental data and an excellent agreement is found. In particular, the calculations are shown to reproduce the evolution of the hole plasmon resonance spectrum as a function of hole diameter, film thickness and hole separation.

  12. Mapping Nanoscale Hotspots with Single-Molecule Emitters Assembled into Plasmonic Nanocavities Using DNA Origami

    Science.gov (United States)

    Chikkaraddy, Rohit; Turek, V. A.; Kongsuwan, Nuttawut; Benz, Felix; Carnegie, Cloudy; van de Goor, Tim; de Nijs, Bart; Demetriadou, Angela; Hess, Ortwin; Keyser, Ulrich F.; Baumberg, Jeremy J.

    2018-01-01

    Fabricating nanocavities in which optically-active single quantum emitters are precisely positioned, is crucial for building nanophotonic devices. Here we show that self-assembly based on robust DNA-origami constructs can precisely position single molecules laterally within sub-5nm gaps between plasmonic substrates that support intense optical confinement. By placing single-molecules at the center of a nanocavity, we show modification of the plasmon cavity resonance before and after bleaching the chromophore, and obtain enhancements of $\\geq4\\times10^3$ with high quantum yield ($\\geq50$%). By varying the lateral position of the molecule in the gap, we directly map the spatial profile of the local density of optical states with a resolution of $\\pm1.5$ nm. Our approach introduces a straightforward non-invasive way to measure and quantify confined optical modes on the nanoscale.

  13. Mapping Nanoscale Hotspots with Single-Molecule Emitters Assembled into Plasmonic Nanocavities Using DNA Origami.

    Science.gov (United States)

    Chikkaraddy, Rohit; Turek, V A; Kongsuwan, Nuttawut; Benz, Felix; Carnegie, Cloudy; van de Goor, Tim; de Nijs, Bart; Demetriadou, Angela; Hess, Ortwin; Keyser, Ulrich F; Baumberg, Jeremy J

    2018-01-10

    Fabricating nanocavities in which optically active single quantum emitters are precisely positioned is crucial for building nanophotonic devices. Here we show that self-assembly based on robust DNA-origami constructs can precisely position single molecules laterally within sub-5 nm gaps between plasmonic substrates that support intense optical confinement. By placing single-molecules at the center of a nanocavity, we show modification of the plasmon cavity resonance before and after bleaching the chromophore and obtain enhancements of ≥4 × 10 3 with high quantum yield (≥50%). By varying the lateral position of the molecule in the gap, we directly map the spatial profile of the local density of optical states with a resolution of ±1.5 nm. Our approach introduces a straightforward noninvasive way to measure and quantify confined optical modes on the nanoscale.

  14. Stacked optical antennas for plasmon propagation in a 5 nm-confined cavity

    KAUST Repository

    Saeed, A.; Panaro, S.; Zaccaria, R. Proietti; Raja, W.; Liberale, Carlo; Dipalo, M.; Messina, G. C.; Wang, H.; De Angelis, F.; Toma, A.

    2015-01-01

    The sub-wavelength concentration and propagation of electromagnetic energy are two complementary aspects of plasmonics that are not necessarily co-present in a single nanosystem. Here we exploit the strong nanofocusing properties of stacked optical antennas in order to highly concentrate the electromagnetic energy into a 5nm metal-insulator-metal (MIM) cavity and convert free radiation into guided modes. The proposed nano-architecture combines the concentration properties of optical nanoantennas with the propagation capability of MIM systems, paving the way to highly miniaturized on-chip plasmonic waveguiding. © 2015, Nature Publishing Group. All rights reserved.

  15. Stacked optical antennas for plasmon propagation in a 5 nm-confined cavity

    KAUST Repository

    Saeed, A.

    2015-06-09

    The sub-wavelength concentration and propagation of electromagnetic energy are two complementary aspects of plasmonics that are not necessarily co-present in a single nanosystem. Here we exploit the strong nanofocusing properties of stacked optical antennas in order to highly concentrate the electromagnetic energy into a 5nm metal-insulator-metal (MIM) cavity and convert free radiation into guided modes. The proposed nano-architecture combines the concentration properties of optical nanoantennas with the propagation capability of MIM systems, paving the way to highly miniaturized on-chip plasmonic waveguiding. © 2015, Nature Publishing Group. All rights reserved.

  16. Modeling, fabrication and high power optical characterization of plasmonic waveguides

    DEFF Research Database (Denmark)

    Lavrinenko, Andrei; Lysenko, Oleg

    2015-01-01

    This paper describes modeling, fabrication and high power optical characterization of thin gold films embedded in silicon dioxide. The propagation vector of surface plasmon polaritons has been calculated by the effective index method for the wavelength range of 750-1700 nm and film thickness of 15......, 30 and 45 nm. The fabrication process of such plasmonic waveguides with width in the range of 1-100 μm and their quality inspection are described. The results of optical characterization of plasmonic waveguides using a high power laser with the peak power wavelength 1064 nm show significant deviation...... from the linear propagation regime of surface plasmon polaritons at the average input power of 100 mW and above. Possible reasons for this deviation are heating of the waveguides and subsequent changes in the coupling and propagation losses....

  17. Surface plasmon optics for biosensors with advanced sensitivity and throughput

    International Nuclear Information System (INIS)

    Toma, M.

    2012-01-01

    Plasmonic biosensors represent a rapidly advancing technology which enables rapid and sensitive analysis of target analytes. This thesis focuses on novel metallic and polymer structures for plasmonic biosensors based on surface plasmon resonance (SPR) and surface plasmon-enhanced fluorescence (SPF). It comprises four projects addressing key challenges concerning the enhancement of sensitivity and throughput. In the project 1, an advanced optical platform is developed which relies on reference-compensated angular spectroscopy of hydrogel-guided waves. The developed optical setup provides superior refractive index resolution of 1.2×10 -7 RIU and offers an attractive platform for direct detection of small analytes which cannot be analyzed by regular SPR biosensors. The project 2 carries out theoretical study of SPR imaging with advanced lateral resolution by utilizing Bragg scattered surface plasmons (BSSPs) on sub-wavelength metallic gratings. The results reveal that the proposed concept provides better lateral resolution and fidelity of the images. This feature opens ways for high-throughput SPR biosensors with denser arrays of sensing spots. The project 3 investigates surface plasmon coupled-emission from fluorophores in the vicinity of plasmonic Bragg-gratings. The experimental results provide leads on advancing the collection efficiency of fluorescence light by controlling the directions of fluorescence emission. This functionality can directly improve the sensitivity of fluorescence-based assays. In the last project 4, a novel sensing scheme with actively tuneable plasmonic structures is developed by employing thermo-responsive hydrogel binding matrix. The hydrogel film simultaneously serves as a large capacity binding matrix and provides means for actuating of surface plasmons through reversible swelling and collapsing of the hydrogel. This characteristic is suitable for multiplexing of sensing channels in fluorescence-based biosensor scheme (author)

  18. Surface plasmon resonance optical cavity enhanced refractive index sensing

    Czech Academy of Sciences Publication Activity Database

    Giorgini, A.; Avino, S.; Malara, P.; Gagliardi, G.; Casalino, M.; Coppola, G.; Iodice, M.; Adam, Pavel; Chadt, Karel; Homola, Jiří; De Natale, P.

    2013-01-01

    Roč. 38, č. 11 (2013), s. 1951-1953 ISSN 0146-9592 R&D Projects: GA ČR GBP205/12/G118 Institutional support: RVO:67985882 Keywords : Resonators * Surface plasmons * Optical sensing and sensors Subject RIV: BH - Optics, Masers, Lasers Impact factor: 3.179, year: 2013

  19. Optimization of extraordinary optical absorption in plasmonic and dielectric structures

    DEFF Research Database (Denmark)

    Dühring, Maria Bayard; Sigmund, Ole

    2013-01-01

    Extraordinary optical absorption (EOA) can be obtained by plasmonic surface structuring. However, studies that compare the performance of these plasmonic devices with similar structured dielectric devices are rarely found in the literature. In this work we show different methods to enhance the EOA...... by optimizing the geometry of the surface structuring for both plasmonic and dielectric devices, and the optimized performances are compared. Two different problem types with periodic structures are considered. The first case shows that strips of silicon on a surface can increase the absorption in an underlying...... it is important to compare the absorption performance of plasmonic devices with similarly structured dielectric devices in order to find the best possible solution....

  20. Integrated optical isolators using magnetic surface plasmon (Presentation Recording)

    Science.gov (United States)

    Shimizu, Hiromasa; Kaihara, Terunori; Umetsu, Saori; Hosoda, Masashi

    2015-09-01

    Optical isolators are one of the essential components to protect semiconductor laser diodes (LDs) from backward reflected light in integrated optics. In order to realize optical isolators, nonreciprocal propagation of light is necessary, which can be realized by magnetic materials. Semiconductor optical isolators have been strongly desired on Si and III/V waveguides. We have developed semiconductor optical isolators based on nonreciprocal loss owing to transverse magneto-optic Kerr effect, where the ferromagnetic metals are deposited on semiconductor optical waveguides1). Use of surface plasmon polariton at the interface of ferromagnetic metal and insulator leads to stronger optical confinement and magneto-optic effect. It is possible to modulate the optical confinement by changing the magnetic field direction, thus optical isolator operation is proposed2, 3). We have investigated surface plasmons at the interfaces between ferrimagnetic garnet/gold film, and applications to waveguide optical isolators. We assumed waveguides composed of Au/Si(38.63nm)/Ce:YIG(1700nm)/Si(220nm)/Si , and calculated the coupling lengths between Au/Si(38.63nm)/Ce:YIG plasmonic waveguide and Ce:YIG/Si(220nm)/Si waveguide for transversely magnetized Ce:YIG with forward and backward directions. The coupling length was calculated to 232.1um for backward propagating light. On the other hand, the coupling was not complete, and the length was calculated to 175.5um. The optical isolation by using the nonreciprocal coupling and propagation loss was calculated to be 43.7dB when the length of plasmonic waveguide is 700um. 1) H. Shimizu et al., J. Lightwave Technol. 24, 38 (2006). 2) V. Zayets et al., Materials, 5, 857-871 (2012). 3) J. Montoya, et al, J. Appl. Phys. 106, 023108, (2009).

  1. Tailoring optical complex field with spiral blade plasmonic vortex lens

    Science.gov (United States)

    Rui, Guanghao; Zhan, Qiwen; Cui, Yiping

    2015-01-01

    Optical complex fields have attracted increasing interests because of the novel effects and phenomena arising from the spatially inhomogeneous state of polarizations and optical singularities of the light beam. In this work, we propose a spiral blade plasmonic vortex lens (SBPVL) that offers unique opportunities to manipulate these novel fields. The strong interaction between the SBPVL and the optical complex fields enable the synthesis of highly tunable plasmonic vortex. Through theoretical derivations and numerical simulations we demonstrated that the characteristics of the plasmonic vortex are determined by the angular momentum (AM) of the light, and the geometrical topological charge of the SBPVL, which is govern by the nonlinear superposition of the pitch and the number of blade element. In addition, it is also shown that by adjusting the geometric parameters, SBPVL can be utilized to focus and manipulate optical complex field with fractional AM. This miniature plasmonic device may find potential applications in optical trapping, optical data storage and many other related fields. PMID:26335894

  2. Optical fiber plasmonic lens for near-field focusing fabricated through focused ion beam

    Science.gov (United States)

    Sloyan, Karen; Melkonyan, Henrik; Moreira, Paulo; Dahlem, Marcus S.

    2017-02-01

    We report on numerical simulations and fabrication of an optical fiber plasmonic lens for near-field focusing applications. The plasmonic lens consists of an Archimedean spiral structure etched through a 100 nm-thick Au layer on the tip of a single-mode SM600 optical fiber operating at a wavelength of 632:8 nm. Three-dimensional finite-difference time-domain computations show that the relative electric field intensity of the focused spot increases 2:1 times when the number of turns increases from 2 to 12. Furthermore, a reduction of the intensity is observed when the initial inner radius is increased. The optimized plasmonic lens focuses light into a spot with a full-width at half-maximum of 182 nm, beyond the diffraction limit. The lens was fabricated by focused ion beam milling, with a 200nm slit width.

  3. Plasmonic optical antenna design for performing tip-enhanced Raman spectroscopy and microscopy

    International Nuclear Information System (INIS)

    Kharintsev, S S; Fishman, A I; Salakhov, M Kh; Hoffmann, G G

    2013-01-01

    This paper highlights optical plasmonic antennas designed with dc-pulsed low-voltage electrochemical etching of a gold wire for implementing tip-enhanced Raman scattering (TERS) measurements. We demonstrate a versatile electrochemical system that allows one to engineer TERS-active metallic gold tips with diverse shapes and sizes in a highly reproducible fashion. The underlying etching mechanism at a voltage-driven meniscus around a gold wire immersed into an electrolyte is discussed in detail. We show that the developed method is suitable to produce not only the simplest geometries such as cones and spheroids, but more complex designs. Attempts have been made to design plasmonic tapered antennas with quasi-uniformly spaced nano-sized bumps on the mesoscopic zone for the extra surface plasmon-light coupling. The capability of the patterned antenna to enhance and localize optical fields is demonstrated with near-field Raman microscopy and spectroscopy of single-walled carbon nanotubes bundles. (paper)

  4. Spontaneous Self-Formation of 3D Plasmonic Optical Structures.

    Science.gov (United States)

    Choi, Inhee; Shin, Yonghee; Song, Jihwan; Hong, SoonGweon; Park, Younggeun; Kim, Dongchoul; Kang, Taewook; Lee, Luke P

    2016-08-23

    Self-formation of colloidal oil droplets in water or water droplets in oil not only has been regarded as fascinating fundamental science but also has been utilized in an enormous number of applications in everyday life. However, the creation of three-dimensional (3D) architectures by a liquid droplet and an immiscible liquid interface has been less investigated than other applications. Here, we report interfacial energy-driven spontaneous self-formation of a 3D plasmonic optical structure at room temperature without an external force. Based on the densities and interfacial energies of two liquids, we simulated the spontaneous formation of a plasmonic optical structure when a water droplet containing metal ions meets an immiscible liquid polydimethylsiloxane (PDMS) interface. At the interface, the metal ions in the droplet are automatically reduced to form an interfacial plasmonic layer as the liquid PDMS cures. The self-formation of both an optical cavity and integrated plasmonic nanostructure significantly enhances the fluorescence by a magnitude of 1000. Our findings will have a huge impact on the development of various photonic and plasmonic materials as well as metamaterials and devices.

  5. Imaging slit-coupled surface plasmon polaritons using conventional optical microscopy.

    Science.gov (United States)

    Mehfuz, R; Chowdhury, F A; Chau, K J

    2012-05-07

    We develop a technique that now enables surface plasmon polaritons (SPPs) coupled by nano-patterned slits in a metal film to be detected using conventional optical microscopy with standard objective lenses. The crux of this method is an ultra-thin polymer layer on the metal surface, whose thickness can be varied over a nanoscale range to enable controllable tuning of the SPP momentum. At an optimal layer thickness for which the SPP momentum matches the momentum of light emerging from the slit, the SPP coupling efficiency is enhanced about six times relative to that without the layer. The enhanced efficiency results in distinctive and bright plasmonic signatures near the slit visible by naked eye under an optical microscope. We demonstrate how this capability can be used for parallel measurement through a simple experiment in which the SPP propagation distance is extracted from a single microscope image of an illuminated array of nano-patterned slits on a metal surface. We also use optical microscopy to image the focal region of a plasmonic lens and obtain results consistent with a previously-reported results using near-field optical microscopy. Measurement of SPPs near a nano-slit using conventional and widely-available optical microscopy is an important step towards making nano-plasmonic device technology highly accessible and easy-to-use.

  6. Optical invisibility through metasurfaces made of plasmonic nanoparticles

    Science.gov (United States)

    Monti, A.; Alù, A.; Toscano, A.; Bilotti, F.

    2015-03-01

    In this paper, we investigate the application of the mantle cloaking technique to near-infrared and visible frequencies, analyzing and designing thin covers consisting of 2D arrays of plasmonic nanoparticles. First, we validate and generalize an analytical model recently appeared in the literature to describe a 2D array of plasmonic nanoparticles as a metasurface characterized by its homogenized surface reactance. We prove that the proposed model allows to efficiently design 2D mantle cloaks with an assigned surface reactance, enabling, thus, the extension of the mantle cloaking technique to optical frequencies. Then, we design realistic optical mantle cloaks made of 2D arrays of spheroidal plasmonic nanoparticles with a high eccentricity. We show that the proposed cloaks allow significant, moderately broadband cloaking effects at visible frequencies. In our designs, we consider realistic losses and non-critical nanoparticle dimensions to envision a practical realization of the proposed cloaks.

  7. Subnanometric stabilization of plasmon-enhanced optical microscopy

    International Nuclear Information System (INIS)

    Yano, Taka-aki; Ichimura, Taro; Kuwahara, Shota; Verma, Prabhat; Kawata, Satoshi

    2012-01-01

    We have demonstrated subnanometric stabilization of tip-enhanced optical microscopy under ambient condition. Time-dependent thermal drift of a plasmonic metallic tip was optically sensed at subnanometer scale, and was compensated in real-time. In addition, mechanically induced displacement of the tip, which usually occurs when the amount of tip-applied force varies, was also compensated in situ. The stabilization of tip-enhanced optical microscopy enables us to perform long-time and robust measurement without any degradation of optical signal, resulting in true nanometric optical imaging with high reproducibility and high precision. The technique presented is applicable for AFM-based nanoindentation with subnanometric precision. (paper)

  8. Biochemical component identification by plasmonic improved whispering gallery mode optical resonance based sensor

    Science.gov (United States)

    Saetchnikov, Vladimir A.; Tcherniavskaia, Elina A.; Saetchnikov, Anton V.; Schweiger, Gustav; Ostendorf, Andreas

    2014-05-01

    Experimental data on detection and identification of variety of biochemical agents, such as proteins, microelements, antibiotic of different generation etc. in both single and multi component solutions under varied in wide range concentration analyzed on the light scattering parameters of whispering gallery mode optical resonance based sensor are represented. Multiplexing on parameters and components has been realized using developed fluidic sensor cell with fixed in adhesive layer dielectric microspheres and data processing. Biochemical component identification has been performed by developed network analysis techniques. Developed approach is demonstrated to be applicable both for single agent and for multi component biochemical analysis. Novel technique based on optical resonance on microring structures, plasmon resonance and identification tools has been developed. To improve a sensitivity of microring structures microspheres fixed by adhesive had been treated previously by gold nanoparticle solution. Another technique used thin film gold layers deposited on the substrate below adhesive. Both biomolecule and nanoparticle injections caused considerable changes of optical resonance spectra. Plasmonic gold layers under optimized thickness also improve parameters of optical resonance spectra. Biochemical component identification has been also performed by developed network analysis techniques both for single and for multi component solution. So advantages of plasmon enhancing optical microcavity resonance with multiparameter identification tools is used for development of a new platform for ultra sensitive label-free biomedical sensor.

  9. Propagation of plasmons in designed single crystalline silver nanostructures

    DEFF Research Database (Denmark)

    Kumar, Shailesh; Lu, Ying-Wei; Huck, Alexander

    2012-01-01

    We demonstrate propagation of plasmons in single crystalline silver nanostructures fabricated using a combination of a bottom-up and a top-down approach. Silver nanoplates of thickness around 65 nm and a surface area of about 100 μm2 are made using a wet chemical method. Silver nanotips...

  10. Optical enhancement effects of plasmonic nanostructures on organic photovoltaic cells

    KAUST Repository

    Park, Hui Joon

    2015-04-01

    © 2015 Hui Joon Park and L. Jay Guo. Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. All rights reserved. In this article, the optical enhancement effects of plasmonic nanostructures on OPV cells were reviewed as an effective way to resolve the mismatch problems between the short exciton diffusion length in organic semiconductors (around 10 nm) and the large thickness required to fully absorb sunlight (e.g. hundreds of nanometers). Especially, the performances of OPVs with plasmonic nanoparticles in photoactive and buffer layers and with periodic nanostructures were investigated. Furthermore, nanoimprint lithography-based nanofabrication processes that can easily control the dimension and uniformity of structures for large-area and uniform plasmonic nanostructures were demonstrated.

  11. Electro-optic polymeric reflection modulator based on plasmonic metamaterial

    Science.gov (United States)

    Abbas, A.; Swillam, M.

    2018-02-01

    A novel low power design for polymeric Electro-Optic reflection modulator is proposed based on the Extraordinary Reflection of light from multilayer structure consisting of a plasmonic metasurface with a periodic structure of sub wavelength circular apertures in a gold film above a thin layer of EO polymer and above another thin gold layer. The interference of the different reflected beams from different layer construct the modulated beam, The applied input driving voltage change the polymer refractive index which in turn determine whether the interference is constructive or destructive, so both phase and intensity modulation could be achieved. The resonant wavelength is tuned to the standard telecommunication wavelength 1.55μm, at this wavelength the reflection is minimum, while the absorption is maximum due to plasmonic resonance (PR) and the coupling between the incident light and the plasmonic metasurface.

  12. Single-Molecule Detection in Nanogap-Embedded Plasmonic Gratings

    Directory of Open Access Journals (Sweden)

    Biyan Chen

    2015-07-01

    Full Text Available We introduce nanogap-embedded silver plasmonic gratings for single-molecule (SM visualization using an epifluorescence microscope. This silver plasmonic platform was fabricated by a cost-effective nano-imprint lithography technique, using an HD DVD template. DNA/ RNA duplex molecules tagged with Cy3/Cy5 fluorophores were immobilized on SiO 2 -capped silver gratings. Light was coupled to the gratings at particular wavelengths and incident angles to form surface plasmons. The SM fluorescence intensity of the fluorophores at the nanogaps showed approximately a 100-fold mean enhancement with respect to the fluorophores observed on quartz slides using an epifluorescence microscope. This high level of enhancement was due to the concentration of surface plasmons at the nanogaps. When nanogaps imaged with epifluorescence mode were compared to quartz imaged using total internal reflection fluorescence (TIRF microscopy, more than a 30-fold mean enhancement was obtained. Due to the SM fluorescence enhancement of plasmonic gratings and the correspondingly high emission intensity, the required laser power can be reduced, resulting in a prolonged detection time prior to photobleaching. This simple platform was able to perform SM studies with a low-cost epifluorescence apparatus, instead of the more expensive TIRF or confocal microscopes, which would enable SM analysis to take place in most scientific laboratories.

  13. Toward single-molecule detection with sensors based on propagating surface plasmons

    Czech Academy of Sciences Publication Activity Database

    Kvasnička, Pavel; Chadt, Karel; Vala, Milan; Bocková, Markéta; Homola, Jiří

    2012-01-01

    Roč. 37, č. 2 (2012), s. 163-165 ISSN 0146-9592 R&D Projects: GA AV ČR KAN200670701; GA MŠk OC09058; GA MŠk(CZ) LH11102 Institutional research plan: CEZ:AV0Z20670512 Keywords : optical biosenzor * single molecule * surface plasmon microscopy Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 3.385, year: 2012

  14. Plasmon assisted optical trapping: fundamentals and biomedical applications

    Science.gov (United States)

    Serafetinides, Alexandros A.; Makropoulou, Mersini; Tsigaridas, Georgios N.; Gousetis, Anastasios

    2015-01-01

    The field of optical trapping has dramatically grown due to implementation in various arenas including physics, biology, medicine and nanotechnology. Certainly, optical tweezers are an invaluable tool to manipulate a variation of particles, such as small dielectric spheres, cells, bacteria, chromosomes and even genes, by highly focused laser beams through microscope. As the main disadvantage of the conventional optical trapping systems is the diffraction limit of the incident light, plasmon assisted nanotrapping is reported as a suitable technique for trapping sub-wavelength metallic or dielectric particles. In this work, firstly, we report briefly on the basic theory of plasmon excitation, focusing on the interaction of nanoscale metallic structures with laser light. Secondly, experimental and numerical simulation results are also presented, demonstrating enhancement of the trapping efficiency of glass or SiO2 substrates, coated with Au and Ag nanostructures, with or without nanoparticles. The optical forces were calculated by measuring the particle's escape velocity calibration method. Finally, representative applications of plasmon assisted optical trapping are reviewed, from cancer therapeutics to fundamental biology and cell nanosurgery.

  15. Ion beam induced optical and surface modification in plasmonic nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Udai B., E-mail: udaibhansingh123@gmail.com; Gautam, Subodh K.; Kumar, Sunil; Hooda, Sonu; Ojha, Sunil; Singh, Fouran

    2016-07-15

    In present work, ion irradiation induced nanostructuring has been exploited as an efficient and effective tool for synthesis of coupled plasmonics nanostructures by using 1.2 MeV Xe ions on Au/ZnO/Au system deposited on glass substrate. The results are correlated on the basis of their optical absorption, surface morphologies and enhanced sensitivity of evolved phonon modes by using UV Visible spectroscopy, scanning electron microscopy (SEM), and Raman spectroscopy (RS), respectively. Optical absorbance spectra of plasmonic nanostructures (NSs) show a decrease in band gap, which may be ascribed to the formation of defects with ion irradiation. The surface morphology reveals the formation of percolated NSs upon ion irradiation and Rutherford backscattering spectrometry (RBS) study clearly shows the formation of multilayer system. Furthermore, RS measurements on samples are studied to understand the enhanced sensitivity of ion irradiation induced phonon mode at 573 cm{sup −1} along with other modes. As compared to pristine sample, a stronger and pronounced evolution of these phonon modes is observed with further ion irradiation, which indicates localized surface plasmon results with enhanced intensity of phonon modes of Zinc oxide (ZnO) material. Thus, such plasmonic NSs can be used as surface enhanced Raman scattering (SERS) substrates.

  16. Chip-integrated ultrawide-band all-optical logic comparator in plasmonic circuits.

    Science.gov (United States)

    Lu, Cuicui; Hu, Xiaoyong; Yang, Hong; Gong, Qihuang

    2014-01-27

    Optical computing opens up the possibility for the realization of ultrahigh-speed and ultrawide-band information processing. Integrated all-optical logic comparator is one of the indispensable core components of optical computing systems. Unfortunately, up to now, no any nanoscale all-optical logic comparator suitable for on-chip integration applications has been realized experimentally. Here, we report a subtle and effective technical solution to circumvent the obstacles of inherent Ohmic losses of metal and limited propagation length of SPPs. A nanoscale all-optical logic comparator suitable for on-chip integration applications is realized in plasmonic circuits directly. The incident single-bit (or dual-bit) logic signals can be compared and the comparison results are endowed with different logic encodings. An ultrabroad operating wavelength range from 700 to 1000 nm, and an ultrahigh output logic-state contrast-ratio of more than 25 dB are realized experimentally. No high power requirement is needed. Though nanoscale SPP light source and the logic comparator device are integrated into the same plasmonic chip, an ultrasmall feature size is maintained. This work not only paves a way for the realization of complex logic device such as adders and multiplier, but also opens up the possibility for realizing quantum solid chips based on plasmonic circuits.

  17. Angle Dependent Optics of Plasmonic Core-Shell Nanoparticles

    Science.gov (United States)

    2018-02-21

    AFRL-AFOSR-JP-TR-2018-0014 Angle-Dependent Optics of Plasmonic Core-Shell Nanoparticles G.V. Pavan Kumar INDIAN INSTITUTE OF SCIENCE EDUCATION AND... EDUCATION AND RESEARCH 900, NCL Innovation Park, Dr Homi Bhabha Road, Pashan PUNE, 411008 IN 8.  PERFORMING ORGANIZATION      REPORT NUMBER 9...function of spherical co-ordinates: azimuthal and polar angles. Absorption, scattering and emission of light from nanoparticles, especially when they are

  18. Optical properties of electrically connected plasmonic nanoantenna dimer arrays

    Science.gov (United States)

    Zimmerman, Darin T.; Borst, Benjamin D.; Carrick, Cassandra J.; Lent, Joseph M.; Wambold, Raymond A.; Weisel, Gary J.; Willis, Brian G.

    2018-02-01

    We fabricate electrically connected gold nanoantenna arrays of homodimers and heterodimers on silica substrates and present a systematic study of their optical properties. Electrically connected arrays of plasmonic nanoantennas make possible the realization of novel photonic devices, including optical sensors and rectifiers. Although the plasmonic response of unconnected arrays has been studied extensively, the present study shows that the inclusion of nanowire connections modifies the device response significantly. After presenting experimental measurements of optical extinction for unconnected dimer arrays, we compare these to measurements of dimers that are interconnected by gold nanowire "busbars." The connected devices show the familiar dipole response associated with the unconnected dimers but also show a second localized surface plasmon resonance (LSPR) that we refer to as the "coupled-busbar mode." Our experimental study also demonstrates that the placement of the nanowire along the antenna modifies the LSPR. Using finite-difference time-domain simulations, we confirm the experimental results and investigate the variation of dimer gap and spacing. Changing the dimer gap in connected devices has a significantly smaller effect on the dipole response than it does in unconnected devices. On the other hand, both LSPR modes respond strongly to changing the spacing between devices in the direction along the interconnecting wires. We also give results for the variation of E-field strength in the dimer gap, which will be important for any working sensor or rectenna device.

  19. Optical manipulation and catalytic activity enhanced by surface plasmon effect

    Science.gov (United States)

    Zou, Ningmu; Min, Jiang; Jiao, Wenxiang; Wang, Guanghui

    2017-02-01

    For optical manipulation, a nano-optical conveyor belt consisting of an array of gold plasmonic non-concentric nano-rings (PNNRs) is demonstrated for the realization of trapping and unidirectional transportation of nanoparticles by polarization rotation of excitation beam. These hot spots of an asymmetric plasmonic nanostructure are polarization dependent, therefore, one can use the incident polarization state to manipulate the trapped targets. Trapped particles could be transferred between adjacent PNNRs in a given direction just by rotating the polarization of incident beam due to unbalanced potential. The angular dependent distribution of electric field around PNNR has been solved using the three- dimensional finite-difference time-domain (FDTD) technique. For optical enhanced catalytic activity, the spectral properties of dimers of Au nanorod-Au nanorod nanostructures under the excitation of 532nm photons have been investigated. With a super-resolution catalytic mapping technique, we identified the existence of "hot spot" in terms of catalytic reactivity at the gap region within the twined plasmonic nanostructure. Also, FDTD calculation has revealed an intrinsic correlation between hot electron transfer.

  20. Application of STEM/EELS to Plasmon-Related Effects in Optical Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Camden, Jon [Univ. of Notre Dame, IN (United States). Dept. of Chemistry and Biochemistry

    2017-08-15

    In this project we employed EELS/STEM to understand the near-field enhancements that drive current applications of plasmonic nanostructures. In particular, we explore the connection between optical and electron excitation of plasmon modes in metallic nanostructures: (1) Probing the structural parameters and dielectric properties of multimetallic nanoparticles; (2) Characterization of the near-electric-field enhancements obtained upon excitation of the localized surface plasmon resonance and understand the connection between electron- and photon-driven plasmons; (3) Understanding the behavior of molecules in plasmon-enhanced fields which is essential to emerging applications such as plasmon-assisted catalysis and solar energy harvesting.

  1. Generation and Controlled Routing of Single Plasmons on a Chip

    DEFF Research Database (Denmark)

    Kumar, Shailesh; Israelsen, Niels Møller; Huck, Alexander

    2014-01-01

    We demonstrate the excitation of single surface plasmon polaritons on a silver nanowire using a nitrogen vacancy center and the subsequent controlled coupling to a second silver nanowire. The coupling efficiency and thus the splitting ratio between the nanowires is controlled by adjusting the gap...... size between the wires with an atomic force microscope. By numerical methods, we estimate the splitting ratios for different gap sizes, and the results support the values obtained in the experiment.......We demonstrate the excitation of single surface plasmon polaritons on a silver nanowire using a nitrogen vacancy center and the subsequent controlled coupling to a second silver nanowire. The coupling efficiency and thus the splitting ratio between the nanowires is controlled by adjusting the gap...

  2. Ultrathin and Nanostructured Au Films with Gradient of Effective Thickness. Optical and Plasmonic Properties

    International Nuclear Information System (INIS)

    Tomilin, S V; Berzhansky, V N; Shaposhnikov, A N; Prokopov, A R; Milyukova, E T; Karavaynikov, A V; Tomilina, O A

    2016-01-01

    In present work the results of investigation of optical (transmission spectra) and plasmonic (surface plasmon-polariton resonance) properties of ultrathin and nanostructured Au films are presents. Methods and techniques for the syntheses of samples of ultrathin and nanostructured metallic films, and for the experimental studies of optical and plasmonic properties are representative. Au films on SiO 2 (optic glass) substrates were investigated. (paper)

  3. Impedance Conjugate Matching of Plasmonic Nanoantenna in Optical Nanocircuits

    DEFF Research Database (Denmark)

    Sachkou, Yauhen; Andryieuski, Andrei; Lavrinenko, Andrei

    2011-01-01

    -shaped optical nanoantenna on its geometrical parameters. We show that several parameters – an arm length of the T-shaped nanoantenna, nanoantenna width and a width of the front facet of the connector – can influence on the impedance conjugate matching which gives flexibility in impedance tuning for coupling......Optical antennas are a state-of-the-art concept in modern plasmonics. Nanoantennas can be advantageously used to localize, enhance and detect radiation in nanoscale volumes. These abilities unlock an enormous potential applications ranging from optoelectronics engineering and integrated optical...... nanocircuitry to nanoscale optical microscopy and ultra-sensing. The coupling efficiency between nanoantenna and other elements in integrated optical nanocircuit strongly depends on its properties where the impedance matching plays a crucial role. We investigate the dependence of impedance of the T...

  4. Nanofabrication of Plasmonic Circuits Containing Single Photon Sources

    DEFF Research Database (Denmark)

    Siampour, Hamidreza; Kumar, Shailesh; Bozhevolnyi, Sergey I.

    2017-01-01

    Nanofabrication of photonic components based on dielectric loaded surface plasmon polariton waveguides (DLSPPWs) excited by single nitrogen vacancy (NV) centers in nanodiamonds is demonstrated. DLSPPW circuits are built around NV containing nanodiamonds, which are certified to be single-photon...... emitters, using electron-beam lithography of hydrogen silsesquioxane (HSQ) resist on silver-coated silicon substrates. A propagation length of 20 ± 5 μm for the NV single-photon emission is measured with DLSPPWs. A 5-fold enhancement in the total decay rate, and 58% coupling efficiency to the DLSPPW mode...

  5. Hybrid plasmonic systems: from optical transparencies to strong coupling and entanglement

    Science.gov (United States)

    Gray, Stephen K.

    2018-02-01

    Classical electrodynamics and quantum mechanical models of quantum dots and molecules interacting with plasmonic systems are discussed. Calculations show that just one quantum dot interacting with a plasmonic system can lead to interesting optical effects, including optical transparencies and more general Fano resonance features that can be tailored with ultrafast laser pulses. Such effects can occur in the limit of moderate coupling between quantum dot and plasmonic system. The approach to the strong coupling regime is also discussed. In cases with two or more quantum dots within a plasmonic system, the possibility of quantum entanglement mediated through the dissipative plasmonic structure arises.

  6. Novel spectral fiber optic sensor based on surface plasmon resonance

    Czech Academy of Sciences Publication Activity Database

    Slavík, Radan; Homola, Jiří; Čtyroký, Jiří; Brynda, Eduard

    B74, 1/3 (2001), s. 106-111 ISSN 0925-4005. [European Conference on Optical Chemical Sensors and Biosensors EUROPT(R)ODE /5./. Lyon-Villeurbanne, 16.04.2000-19.04.2000] R&D Projects: GA ČR GA102/99/M057; GA ČR GA102/99/0549; GA ČR GA102/00/1536 Institutional research plan: CEZ:AV0Z2067918 Keywords : fibre optic sensors * surface plasmons Subject RIV: JB - Sensors, Measurment, Regulation Impact factor: 1.440, year: 2001

  7. Integrated Optical Components Utilizing Long-Range Surface Plasmon Polaritons

    DEFF Research Database (Denmark)

    Boltasseva, Alexandra; Nikolajsen, Thomas; Leosson, Kristjan

    2005-01-01

    New optical waveguide technology for integrated optics, based on propagation of long-range surface plasmon polaritons (LR-SPPs) along metal stripes embedded in dielectric, is presented. Guiding and routing of electromagnetic radiation along nanometer-thin and micrometer-wide gold stripes embedded......), and a bend loss of ~5 dB for a bend radius of 15 mm are evaluated for 15-nm-thick and 8-mm-wide stripes at the wavelength of 1550 nm. LR-SPP-based 3-dB power Y-splitters, multimode interference waveguides, and directional couplers are demonstrated and investigated. At 1570 nm, coupling lengths of 1.9 and 0...

  8. Surface plasmon enhanced third-order optical nonlinearity of Ag nanocomposite film

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Vijender [Department of Applied Science, N.C. College of Engineering, Israna, Panipat 132107, Haryana (India); Aghamkar, Praveen, E-mail: p-aghamkar@yahoo.in [Department of Physics, Chaudhary Devi Lal University, Sirsa 125055, Haryana (India)

    2014-03-17

    We obtain a large third-order optical nonlinearity (χ{sup (3)} ≈ 10{sup −10}esu) of silver nanoparticles dispersed in polyvinyl alcohol/tetraethyl orthosilicate matrix using single beam z-scan technique at 532 nm by Q-switched Nd:YAG laser. We have shown that mechanisms responsible for third-order optical nonlinearity of Ag nanocomposite film are reverse saturable absorption (RSA) and self-defocusing in the purlieu of surface plasmon resonance (SPR). Optical band-gap and width of SPR band of Ag nanocomposite film decrease with increasing silver concentration, which leads to enhancement of local electric field and hence third-order optical nonlinearity. Optical limiting, due to RSA has also been demonstrated at 532 nm.

  9. Surface plasmon enhanced third-order optical nonlinearity of Ag nanocomposite film

    International Nuclear Information System (INIS)

    Singh, Vijender; Aghamkar, Praveen

    2014-01-01

    We obtain a large third-order optical nonlinearity (χ (3)  ≈ 10 −10 esu) of silver nanoparticles dispersed in polyvinyl alcohol/tetraethyl orthosilicate matrix using single beam z-scan technique at 532 nm by Q-switched Nd:YAG laser. We have shown that mechanisms responsible for third-order optical nonlinearity of Ag nanocomposite film are reverse saturable absorption (RSA) and self-defocusing in the purlieu of surface plasmon resonance (SPR). Optical band-gap and width of SPR band of Ag nanocomposite film decrease with increasing silver concentration, which leads to enhancement of local electric field and hence third-order optical nonlinearity. Optical limiting, due to RSA has also been demonstrated at 532 nm

  10. Hydrogen peroxide and glucose concentration measurement using optical fiber grating sensors with corrodible plasmonic nanocoatings.

    Science.gov (United States)

    Zhang, Xuejun; Wu, Ze; Liu, Fu; Fu, Qiangqiang; Chen, Xiaoyong; Xu, Jian; Zhang, Zhaochuan; Huang, Yunyun; Tang, Yong; Guo, Tuan; Albert, Jacques

    2018-04-01

    We propose and demonstrate hydrogen peroxide (H 2 O 2 ) and glucose concentration measurements using a plasmonic optical fiber sensor. The sensor utilizes a tilted fiber Bragg grating (TFBG) written in standard single mode communication fiber. The fiber is over coated with an nm-scale film of silver that supports surface plasmon resonances (SPRs). Such a tilted grating SPR structure provides a high density of narrow spectral resonances (Q-factor about 10 5 ) that overlap with the broader absorption band of the surface plasmon waves in the silver film, thereby providing an accurate tool to measure small shifts of the plasmon resonance frequencies. The H 2 O 2 to be detected acts as an oxidant to etch the silver film, which has the effect of gradually decreasing the SPR attenuation. The etching rate of the silver film shows a clear relationship with the H 2 O 2 concentration so that monitoring the progressively increasing attenuation of a selected surface plasmon resonance over a few minutes enables us to measure the H 2 O 2 concentration with a limit of detection of 0.2 μM. Furthermore, the proposed method can be applied to the determination of glucose in human serum for a concentration range from 0 to 12 mM (within the physiological range of 3-8 mM) by monitoring the H 2 O 2 produced by an enzymatic oxidation process. The sensor does not require accurate temperature control because of the inherent temperature insensitivity of TFBG devices referenced to the core mode resonance. A gold mirror coated on the fiber allows the sensor to work in reflection, which will facilitate the integration of the sensor with a hypodermic needle for in vitro measurements. The present study shows that Ag-coated TFBG-SPR can be applied as a promising type of sensing probe for optical detection of H 2 O 2 and glucose detection in human serum.

  11. Hydrogen peroxide and glucose concentration measurement using optical fiber grating sensors with corrodible plasmonic nanocoatings

    Science.gov (United States)

    Zhang, Xuejun; Wu, Ze; Liu, Fu; Fu, Qiangqiang; Chen, Xiaoyong; Xu, Jian; Zhang, Zhaochuan; Huang, Yunyun; Tang, Yong; Guo, Tuan; Albert, Jacques

    2018-01-01

    We propose and demonstrate hydrogen peroxide (H2O2) and glucose concentration measurements using a plasmonic optical fiber sensor. The sensor utilizes a tilted fiber Bragg grating (TFBG) written in standard single mode communication fiber. The fiber is over coated with an nm-scale film of silver that supports surface plasmon resonances (SPRs). Such a tilted grating SPR structure provides a high density of narrow spectral resonances (Q-factor about 105) that overlap with the broader absorption band of the surface plasmon waves in the silver film, thereby providing an accurate tool to measure small shifts of the plasmon resonance frequencies. The H2O2 to be detected acts as an oxidant to etch the silver film, which has the effect of gradually decreasing the SPR attenuation. The etching rate of the silver film shows a clear relationship with the H2O2 concentration so that monitoring the progressively increasing attenuation of a selected surface plasmon resonance over a few minutes enables us to measure the H2O2 concentration with a limit of detection of 0.2 μM. Furthermore, the proposed method can be applied to the determination of glucose in human serum for a concentration range from 0 to 12 mM (within the physiological range of 3-8 mM) by monitoring the H2O2 produced by an enzymatic oxidation process. The sensor does not require accurate temperature control because of the inherent temperature insensitivity of TFBG devices referenced to the core mode resonance. A gold mirror coated on the fiber allows the sensor to work in reflection, which will facilitate the integration of the sensor with a hypodermic needle for in vitro measurements. The present study shows that Ag-coated TFBG-SPR can be applied as a promising type of sensing probe for optical detection of H2O2 and glucose detection in human serum. PMID:29675315

  12. Plasmonic response and transformation mechanism upon single laser exposure of metal discontinuous films

    Energy Technology Data Exchange (ETDEWEB)

    Rodríguez, C.E. [Laser Processing Group, Instituto de Óptica, CSIC, Serrano 121, 28006 Madrid (Spain); Peláez, R.J., E-mail: rpelaez@io.cfmac.csic.es [Laser Processing Group, Instituto de Óptica, CSIC, Serrano 121, 28006 Madrid (Spain); Afonso, C.N. [Laser Processing Group, Instituto de Óptica, CSIC, Serrano 121, 28006 Madrid (Spain); Riedel, S.; Leiderer, P. [Faculty of Physics, University of Konstanz, Universitätsstraße 10, 78457 Konstanz (Germany); Jimenez-Rey, D.; Font, A. Climent- [Centro de Micro-Análisis de Materiales (CMAM) and Departamento de Física Aplicada, University Autonoma Madrid, 28049 Madrid (Spain)

    2014-05-01

    Ag and Au discontinuous films were exposed to single nanosecond pulses of a homogenized beam of an excimer laser operating at 193 nm. For low fluences, the films convert into big, almost spherical and isolated nanoparticles (NPs) due to laser-induced dewetting. Their optical response exhibits a sharp surface plasmon resonance (SPR) consistent with that of spherical and non-interacting NPs. For higher fluences, the formation of many small NPs and almost no big NPs is observed instead. The SPR features change and the plasmonic response becomes influenced by multipolar interactions among neighbouring NPs. Low and high fluence regimes are respectively related to melting and boiling threshold of the metal, and additionally, craters appear in the latter regime.

  13. Actively addressed single pixel full-colour plasmonic display

    Science.gov (United States)

    Franklin, Daniel; Frank, Russell; Wu, Shin-Tson; Chanda, Debashis

    2017-05-01

    Dynamic, colour-changing surfaces have many applications including displays, wearables and active camouflage. Plasmonic nanostructures can fill this role by having the advantages of ultra-small pixels, high reflectivity and post-fabrication tuning through control of the surrounding media. However, previous reports of post-fabrication tuning have yet to cover a full red-green-blue (RGB) colour basis set with a single nanostructure of singular dimensions. Here, we report a method which greatly advances this tuning and demonstrates a liquid crystal-plasmonic system that covers the full RGB colour basis set, only as a function of voltage. This is accomplished through a surface morphology-induced, polarization-dependent plasmonic resonance and a combination of bulk and surface liquid crystal effects that manifest at different voltages. We further demonstrate the system's compatibility with existing LCD technology by integrating it with a commercially available thin-film-transistor array. The imprinted surface interfaces readily with computers to display images as well as video.

  14. Optical cavity-assisted broadband optical transparency of a plasmonic metal film

    International Nuclear Information System (INIS)

    Liu, Zhengqi; Nie, Yiyou; Yuan, Wen; Liu, Xiaoshan; Huang, Shan; Gao, Huogui; Gu, Gang; Liu, Guiqiang; Chen, Jing

    2015-01-01

    We theoretically present a powerful method to achieve a continuous metal film structure with broadband optical transparency via introducing a dielectric Fabry–Pérot (FP) cavity. An incident optical field could be efficiently coupled and confined with the strong localized plasmons by the non-close-packed plasmonic crystal at the input part and could then become re-radiated output via the transmission channel supported by the dielectric cavity. The formed photonic-plasmonic system could therefore make the seamless metal film structure have a superior near-unity transparency (up to 97%) response and a broadband transparent spectrum with bandwidth >245 nm (with transmittance >90%) in the optical regime. The observed optical properties of the proposed structure can be highly tuned via varying the structural parameters. Based on the colloidal assembly method, the proposed plasmonic crystal can be fabricated in a large area. In addition, the achieved optical transparency can be retained in the extremely roughed metal film structure. Thereby, the findings could offer a feasible way to achieve a broadband transparent metal film structure and hold potential applications in transparent electrodes, touch screens and interactive electronics. (paper)

  15. Optical Properties of Plasmon Resonances with Ag/SiO2/Ag Multi-Layer Composite Nanoparticles

    International Nuclear Information System (INIS)

    Ye-Wan, Ma; Li-Hua, Zhang; Zhao-Wang, Wu; Jie, Zhang

    2010-01-01

    Optical properties of plasmon resonance with Ag/SiO 2 /Ag multi-layer nanoparticles are studied by numerical simulation based on Green's function theory. The results show that compared with single-layer Ag nanoparticles, the multi-layer nanoparticles exhibit several distinctive optical properties, e.g. with increasing the numbers of the multi-layer nanoparticles, the scattering efficiency red shifts, and the intensity of scattering enhances accordingly. It is interesting to find out that slicing an Ag-layer into multi-layers leads to stronger scattering intensity and more 'hot spots' or regions of stronger field enhancement. This property of plasmon resonance of surface Raman scattering has greatly broadened the application scope of Raman spectroscopy. The study of metal surface plasmon resonance characteristics is critical to the further understanding of surface enhanced Raman scattering as well as its applications. (fundamental areas of phenomenology (including applications))

  16. Rod-like plasmonic nanoparticles as optical building blocks: how differences in particle shape and structural geometry influence optical signal

    Energy Technology Data Exchange (ETDEWEB)

    Stender, Anthony [Iowa State Univ., Ames, IA (United States)

    2013-01-01

    Gold nanoparticles, particularly those with an anisotropic shape, have become a popular optical probe for experiments involving work on the nanoscale. However, to carry out such delicate and intricate experiments, it is first necessary to understand the detailed behavior of individual nanoparticles. In this series of experiments, optical and electron microscopy were utilized for the characterization of individual nanoparticles and small assemblies of nanoparticles. In the first experiment, gold nanorods were investigated. Single, isolated nanorods exhibit two maxima of localized surface plasmon resonance (LSPR), which are associated with the two nanorod axes. Upon the physical rotation of a nanorod at one of its LSPR wavelengths under polarized illumination, the optical behavior varies in a sinusoidal fashion. A dimer of nanorods exhibits optical behavior quite similar to a nanorod, except the LSPR maxima are shifted and broader. Under differential interference contrast (DIC) microscopy, a pair of nanorods separated by a distance below the diffraction limit can be distinguished from a single nanorod due to its optical behavior upon rotation. Dark field microscopy is unable to distinguish the two geometries. For the second set of experiments, the optical behavior of single gold nanorods at non-plasmonic wavelengths was investigated. The same nanorod was rotated with respect to a polarized light source under DIC, dark field, and polarized light microscopy. DIC microscopy was found to produce diffraction pattern peaks at non-plasmonic wavelengths, which could be altered by adjusting the setting of the polarizer. In the third set of experiments, the optical behavior of a single gold dumbbell and several simple dumbbell geometries were investigated with microscopy and simulations. The single dumbbell displayed behavior quite similar to that of a nanorod, but dumbbells exhibit a shift in both LSPR wavebands. Moreover, the shape of dumbbell particles allows them to

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

    International Nuclear Information System (INIS)

    Chou Chau, Yuan-Fong; Lim, Chee Ming; Kumara, N. T. R. N.; Yoong, Voo Nyuk; Lee, Chuanyo; Huang, Hung Ji; Lin, Chun-Ting; Chiang, Hai-Pang

    2016-01-01

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

  18. Tunable all-optical plasmonic rectifier in nanoscale metal-insulator-metal waveguides.

    Science.gov (United States)

    Xu, Yi; Wang, Xiaomeng; Deng, Haidong; Guo, Kangxian

    2014-10-15

    We propose a tunable all-optical plasmonic rectifier based on the nonlinear Fano resonance in a metal-insulator-metal plasmonic waveguide and cavities coupling system. We develop a theoretical model based on the temporal coupled-mode theory to study the device physics of the nanoscale rectifier. We further demonstrate via the finite difference time domain numerical experiment that our idea can be realized in a plasmonic system with an ultracompact size of ~120×800  nm². The tunable plasmonic rectifier could facilitate the all-optical signal processing in nanoscale.

  19. Plasmonic Optical Fiber-Grating Immunosensing: A Review.

    Science.gov (United States)

    Guo, Tuan; González-Vila, Álvaro; Loyez, Médéric; Caucheteur, Christophe

    2017-11-26

    Plasmonic immunosensors are usually made of a noble metal (in the form of a film or nanoparticles) on which bioreceptors are grafted to sense analytes based on the antibody/antigen or other affinity mechanism. Optical fiber configurations are a miniaturized counterpart to the bulky Kretschmann prism and allow easy light injection and remote operation. To excite a surface plasmon (SP), the core-guided light is locally outcoupled. Unclad optical fibers were the first configurations reported to this end. Among the different architectures able to bring light in contact with the surrounding medium, a great quantity of research is today being conducted on metal-coated fiber gratings photo-imprinted in the fiber core, as they provide modal features that enable SP generation at any wavelength, especially in the telecommunication window. They are perfectly suited for use with cost-effective high-resolution interrogators, allowing both a high sensitivity and a low limit of detection to be reached in immunosensing. This paper will review recent progress made in this field with different kinds of gratings: uniform, tilted and eccentric short-period gratings as well as long-period fiber gratings. Practical cases will be reported, showing that such sensors can be used in very small volumes of analytes and even possibly applied to in vivo diagnosis.

  20. Plasmonic Optical Fiber-Grating Immunosensing: A Review

    Directory of Open Access Journals (Sweden)

    Tuan Guo

    2017-11-01

    Full Text Available Plasmonic immunosensors are usually made of a noble metal (in the form of a film or nanoparticles on which bioreceptors are grafted to sense analytes based on the antibody/antigen or other affinity mechanism. Optical fiber configurations are a miniaturized counterpart to the bulky Kretschmann prism and allow easy light injection and remote operation. To excite a surface plasmon (SP, the core-guided light is locally outcoupled. Unclad optical fibers were the first configurations reported to this end. Among the different architectures able to bring light in contact with the surrounding medium, a great quantity of research is today being conducted on metal-coated fiber gratings photo-imprinted in the fiber core, as they provide modal features that enable SP generation at any wavelength, especially in the telecommunication window. They are perfectly suited for use with cost-effective high-resolution interrogators, allowing both a high sensitivity and a low limit of detection to be reached in immunosensing. This paper will review recent progress made in this field with different kinds of gratings: uniform, tilted and eccentric short-period gratings as well as long-period fiber gratings. Practical cases will be reported, showing that such sensors can be used in very small volumes of analytes and even possibly applied to in vivo diagnosis.

  1. Self-organized plasmonic metasurfaces for all-optical modulation

    Science.gov (United States)

    Della Valle, G.; Polli, D.; Biagioni, P.; Martella, C.; Giordano, M. C.; Finazzi, M.; Longhi, S.; Duò, L.; Cerullo, G.; Buatier de Mongeot, F.

    2015-06-01

    We experimentally demonstrate a self-organized metasurface with a polarization dependent transmittance that can be dynamically controlled by optical means. The configuration consists of tightly packed plasmonic nanowires with a large dispersion of width and height produced by the defocused ion-beam sputtering of a thin gold film supported on a silica glass. Our results are quantitatively interpreted according to a theoretical model based on the thermomodulational nonlinearity of gold and a finite-element numerical analysis of the absorption and scattering cross-sections of the nanowires. We found that the polarization sensitivity of the metasurface can be strongly enhanced by pumping with ultrashort laser pulses, leading to potential applications in ultrafast all-optical modulation and switching of light.

  2. Plasmon resonance in single- and double-layer CVD graphene nanoribbons

    DEFF Research Database (Denmark)

    Wang, Di; Emani, Naresh K.; Chung, Ting Fung

    2015-01-01

    Dynamic tunability of the plasmonic resonance in graphene nanoribbons is desirable in the near-infrared. We demonstrated a constant blue shift of plasmonic resonances in double-layer graphene nanoribbons with respect to single-layer graphene nanoribbons. © OSA 2015.......Dynamic tunability of the plasmonic resonance in graphene nanoribbons is desirable in the near-infrared. We demonstrated a constant blue shift of plasmonic resonances in double-layer graphene nanoribbons with respect to single-layer graphene nanoribbons. © OSA 2015....

  3. Plasmonic Optical Fiber Sensor Based on Double Step Growth of Gold Nano-Islands

    Directory of Open Access Journals (Sweden)

    José M. M. M. de Almeida

    2018-04-01

    Full Text Available It is presented the fabrication and characterization of optical fiber sensors for refractive index measurement based on localized surface plasmon resonance (LSPR with gold nano-islands obtained by single and by repeated thermal dewetting of gold thin films. Thin films of gold deposited on silica (SiO2 substrates and produced by different experimental conditions were analyzed by Scanning Electron Microscope/Dispersive X-ray Spectroscopy (SEM/EDS and optical means, allowing identifying and characterizing the formation of nano-islands. The wavelength shift sensitivity to the surrounding refractive index of sensors produced by single and by repeated dewetting is compared. While for the single step dewetting, a wavelength shift sensitivity of ~60 nm/RIU was calculated, for the repeated dewetting, a value of ~186 nm/RIU was obtained, an increase of more than three times. It is expected that through changing the fabrication parameters and using other fiber sensor geometries, higher sensitivities may be achieved, allowing, in addition, for the possibility of tuning the plasmonic frequency.

  4. Plasmonic Optical Fiber Sensor Based on Double Step Growth of Gold Nano-Islands

    Science.gov (United States)

    Vasconcelos, Helena

    2018-01-01

    It is presented the fabrication and characterization of optical fiber sensors for refractive index measurement based on localized surface plasmon resonance (LSPR) with gold nano-islands obtained by single and by repeated thermal dewetting of gold thin films. Thin films of gold deposited on silica (SiO2) substrates and produced by different experimental conditions were analyzed by Scanning Electron Microscope/Dispersive X-ray Spectroscopy (SEM/EDS) and optical means, allowing identifying and characterizing the formation of nano-islands. The wavelength shift sensitivity to the surrounding refractive index of sensors produced by single and by repeated dewetting is compared. While for the single step dewetting, a wavelength shift sensitivity of ~60 nm/RIU was calculated, for the repeated dewetting, a value of ~186 nm/RIU was obtained, an increase of more than three times. It is expected that through changing the fabrication parameters and using other fiber sensor geometries, higher sensitivities may be achieved, allowing, in addition, for the possibility of tuning the plasmonic frequency. PMID:29677108

  5. Plasmonic Optical Fiber Sensor Based on Double Step Growth of Gold Nano-Islands.

    Science.gov (United States)

    de Almeida, José M M M; Vasconcelos, Helena; Jorge, Pedro A S; Coelho, Luis

    2018-04-20

    It is presented the fabrication and characterization of optical fiber sensors for refractive index measurement based on localized surface plasmon resonance (LSPR) with gold nano-islands obtained by single and by repeated thermal dewetting of gold thin films. Thin films of gold deposited on silica (SiO₂) substrates and produced by different experimental conditions were analyzed by Scanning Electron Microscope/Dispersive X-ray Spectroscopy (SEM/EDS) and optical means, allowing identifying and characterizing the formation of nano-islands. The wavelength shift sensitivity to the surrounding refractive index of sensors produced by single and by repeated dewetting is compared. While for the single step dewetting, a wavelength shift sensitivity of ~60 nm/RIU was calculated, for the repeated dewetting, a value of ~186 nm/RIU was obtained, an increase of more than three times. It is expected that through changing the fabrication parameters and using other fiber sensor geometries, higher sensitivities may be achieved, allowing, in addition, for the possibility of tuning the plasmonic frequency.

  6. Temperature dependent optical properties of (002) oriented ZnO thin film using surface plasmon resonance

    Science.gov (United States)

    Saha, Shibu; Mehan, Navina; Sreenivas, K.; Gupta, Vinay

    2009-08-01

    Temperature dependent optical properties of c-axis oriented ZnO thin film were investigated using surface plasmon resonance (SPR) technique. SPR data for double layer (prism-Au-ZnO-air) and single layer (prism-Au-air) systems were taken over a temperature range (300-525 K). Dielectric constant at optical frequency and real part of refractive index of the ZnO film shows an increase with temperature. The bandgap of the oriented ZnO film was found to decrease with rise in temperature. The work indicates a promising application of the system as a temperature sensor and highlights an efficient scientific tool to study optical properties of thin film under varying ambient conditions.

  7. Directional radiation of Babinet-inverted optical nanoantenna integrated with plasmonic waveguide

    Science.gov (United States)

    Kim, Jineun; Roh, Young-Geun; Cheon, Sangmo; Jeong Kim, Un; Hwang, Sung Woo; Park, Yeonsang; Lee, Chang-Won

    2015-07-01

    We present a Babinet-inverted optical nanoantenna integrated with a plasmonic waveguide. Using an integrated nanoantenna, we can couple the plasmon guide mode in a metal-insulator-metal (MIM) structure into the resonant antenna feed directly. The resonantly excited feed slot then radiates to free space and generates a magnetic dipole-like far-field pattern. The coupling efficiency of the integrated nanoantenna is calculated as being approximately 19% using a three-dimensional finite-difference time-domain (3D FDTD) simulation. By adding an auxiliary groove structure along with the feed, the radiation direction can be controlled similar to an optical Yagi-Uda antenna. We also determine, both theoretically and experimentally, that groove depth plays a significant role to function groove structure as a reflector or a director. The demonstrated Babinet-inverted optical nanoantenna integrated with a plasmonic waveguide can be used as a “plasmonic via” in plasmonic nanocircuits.

  8. Plasmon excitation in single wall carbon nanotubes by penetrating charged particles

    International Nuclear Information System (INIS)

    Segui, Silvina; Gervasoni, Juana L; Arista, Néstor R; Mowbray, Duncan J; Mišković, Zoran L

    2012-01-01

    In this work we study the excitation of plasmons due to the incidence of a charged particle passing through a single wall carbon nanotube. We use a quantized hydrodynamic, in which the σ and π electrons characteristic of these carbonaceous structures are depicted as two interacting 2-dimensional fluids, to calculate the average number of plasmons excited. We analyze the contribution of the different plasmon modes in a variety of configurations, and study the energy lost by the incident particle.

  9. Spatially Mapping Energy Transfer from Single Plasmonic Particles to Semiconductor Substrates via STEM/EELS.

    Science.gov (United States)

    Li, Guoliang; Cherqui, Charles; Bigelow, Nicholas W; Duscher, Gerd; Straney, Patrick J; Millstone, Jill E; Masiello, David J; Camden, Jon P

    2015-05-13

    Energy transfer from plasmonic nanoparticles to semiconductors can expand the available spectrum of solar energy-harvesting devices. Here, we spatially and spectrally resolve the interaction between single Ag nanocubes with insulating and semiconducting substrates using electron energy-loss spectroscopy, electrodynamics simulations, and extended plasmon hybridization theory. Our results illustrate a new way to characterize plasmon-semiconductor energy transfer at the nanoscale and bear impact upon the design of next-generation solar energy-harvesting devices.

  10. Inelastic x-ray study of plasmons in oriented single and multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Casa, D.M.; Upton, M.H.; Gog, T.; Misewich, J.; Hill, J.P.; Lowndes, D.; Eres, G.

    2006-01-01

    Carbon nanotubes (CNT) have a wide variety of interesting properties and a large number of potential aplications in electronic and optical devices. In this study we concentrate on one important aspect of their electronic stucture: the plasmon dispersions in both single- and multi-wall CNTs and their relation to those in graphite. For the first time inelastic X-ray scattering is used to study these collective electronic excitations in oriented CNT samples. The experiments were performed on the IXS instrument at beamline 9ID CMC-XOR, APS, ANL. The incident energy was defined by a Si(333) monochromator, a spherically bent Ge(733) diced analyzer at the end of a 1-m arm focused the incident radiation onto a solid-state detector. The overall resolution was ∼300 meV FWHM. The incident photons were linearly polarized perpendicular to the scattering plane. Energy loss scans were taken by varying the incident energy while keeping the exit energy fixed at 8.9805 keV. The momentum transfer was kept along the nanotubes axis. Spectra were taken at room temperature. The samples were oriented CNTs (both single- and multi-wall) grown on a Si substrate. The samples referred to as 'single-wall' were in fact a few walls at most (1-5) while the multi-walled ones had ∼12 walls. Fig. 1. shows the inelastic spectra for the single-, multi-wall, and highly oriented pyrolithic graphite (HOPG) from top to bottom. Momentum transfer was Q = 0.79 (angstrom) -1 in all cases, its direction was along the tubes for the first two samples or parallel to the sheets for graphite. The peaks at ∼10 and ∼30 eV are known as the π and σ + π plasmons respectively. Fig. 2. shows the complete dispersion curves for both plasmon modes as a function of momentum transfer for all three samples.

  11. Optical absorption enhancement by inserting ZnO optical spacer in plasmonic organic solar cells

    Science.gov (United States)

    N'Konou, Kekeli; Torchio, Philippe

    2018-01-01

    Optical absorption enhancement (AE) using coupled optical spacer and plasmonic effects in standard and inverted organic solar cells (OSCs) are demonstrated using the finite-difference time-domain numerical method. The influence of an added zinc oxide (ZnO) optical spacer layer inserted below the active layer in standard architecture is first theoretically investigated while the influence of varying the ZnO cathodic buffer layer thickness in inverted design is studied on AE. Then, the embedding of a square periodic array of core-shell silver-silica nanospheres (Ag@SiO2 NSs) at different positions in standard and inverted OSCs is performed while AE and short-circuit current density (Jsc) are calculated. As a result of previous combined effects, the optimized standard plasmonic OSCs present 15% and 79.45% enhancement in J over the reference with and without ZnO optical spacer layer, respectively, and a 16% increase of AE when Ag@SiO2 NSs are placed on top of the PEDOT:PSS layer. Compared to the inverted OSC reference, the plasmonic OSCs present 26% and 27% enhancement in J and AE, respectively, when the Ag@SiO2 NSs are located on top of the ZnO layer. Furthermore, the spatial position of these NSs in such OSCs is a key parameter for increasing light absorption via enhanced electromagnetic field distribution.

  12. Top-down fabrication of plasmonic nanostructures for deterministic coupling to single quantum emitters

    NARCIS (Netherlands)

    Pfaff, W.; Vos, A.; Hanson, R.

    2013-01-01

    Metal nanostructures can be used to harvest and guide the emission of single photon emitters on-chip via surface plasmon polaritons. In order to develop and characterize photonic devices based on emitter-plasmon hybrid structures, a deterministic and scalable fabrication method for such structures

  13. Silicon as a virtual plasmonic material: Acquisition of its transient optical constants and the ultrafast surface plasmon-polariton excitation

    Energy Technology Data Exchange (ETDEWEB)

    Danilov, P. A.; Ionin, A. A.; Kudryashov, S. I., E-mail: sikudr@sci.lebedev.ru; Makarov, S. V.; Rudenko, A. A. [Lebedev Physical Institute (Russian Federation); Saltuganov, P. N. [Moscow Institute of Physics and Technology (State University) (Russian Federation); Seleznev, L. V.; Yurovskikh, V. I.; Zayarny, D. A. [Lebedev Physical Institute (Russian Federation); Apostolova, T. [Bulgarian Academy of Sciences, Institute for Nuclear Research and Nuclear Energetics (Bulgaria)

    2015-06-15

    Ultrafast intense photoexcitation of a silicon surface is complementarily studied experimentally and theoretically, with its prompt optical dielectric function obtained by means of time-resolved optical reflection microscopy and the underlying electron-hole plasma dynamics modeled numerically, using a quantum kinetic approach. The corresponding transient surface plasmon-polariton (SPP) dispersion curves of the photo-excited material were simulated as a function of the electron-hole plasma density, using the derived optical dielectric function model, and directly mapped at several laser photon energies, measuring spatial periods of the corresponding SPP-mediated surface relief nanogratings. The unusual spectral dynamics of the surface plasmon resonance, initially increasing with the increase in the electron-hole plasma density but damped at high interband absorption losses induced by the high-density electron-hole plasma through instantaneous bandgap renormalization, was envisioned through the multi-color mapping.

  14. Ultrafast optical control of terahertz surface plasmons in subwavelength hole-arrays at room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Azad, Abul Kalam [Los Alamos National Laboratory; Chen, Hou - Tong [Los Alamos National Laboratory; Taylor, Antoinette [Los Alamos National Laboratory; O' Hara, John [Los Alamos National Laboratory

    2010-12-10

    Extraordinary optical transmission through subwavelength metallic hole-arrays has been an active research area since its first demonstration. The frequency selective resonance properties of subwavelength metallic hole arrays, generally known as surface plasmon polaritons, have potential use in functional plasmonic devices such as filters, modulators, switches, etc. Such plasmonic devices are also very promising for future terahertz applications. Ultrafast switching or modulation of the resonant behavior of the 2-D metallic arrays in terahertz frequencies is of particular interest for high speed communication and sensing applications. In this paper, we demonstrate optical control of surface plasmon enhanced resonant terahertz transmission in two-dimensional subwavelength metallic hole arrays fabricated on gallium arsenide based substrates. Optically pumping the arrays creates a conductive layer in the substrate reducing the terahertz transmission amplitude of both the resonant mode and the direct transmission. Under low optical fluence, the terahertz transmission is more greatly affected by resonance damping than by propagation loss in the substrate. An ErAs:GaAs nanoisland superlattice substrate is shown to allow ultrafast control with a switching recovery time of {approx}10 ps. We also present resonant terahertz transmission in a hybrid plasmonic film comprised of an integrated array of subwavelength metallic islands and semiconductor holes. A large dynamic transition between a dipolar localized surface plasmon mode and a surface plasmon resonance near 0.8 THz is observed under near infrared optical excitation. The reversal in transmission amplitude from a stopband to a passband and up to {pi}/2 phase shift achieved in the hybrid plasmonic film make it promising in large dynamic phase modulation, optical changeover switching, and active terahertz plasmonics.

  15. Microfluidic device for continuous single cells analysis via Raman spectroscopy enhanced by integrated plasmonic nanodimers

    KAUST Repository

    Perozziello, Gerardo

    2015-12-11

    In this work a Raman flow cytometer is presented. It consists of a microfluidic device that takes advantages of the basic principles of Raman spectroscopy and flow cytometry. The microfluidic device integrates calibrated microfluidic channels- where the cells can flow one-by-one -, allowing single cell Raman analysis. The microfluidic channel integrates plasmonic nanodimers in a fluidic trapping region. In this way it is possible to perform Enhanced Raman Spectroscopy on single cell. These allow a label-free analysis, providing information about the biochemical content of membrane and cytoplasm of the each cell. Experiments are performed on red blood cells (RBCs), peripheral blood lymphocytes (PBLs) and myelogenous leukemia tumor cells (K562). © 2015 Optical Society of America.

  16. Advances in optoplasmonic sensors – combining optical nano/microcavities and photonic crystals with plasmonic nanostructures and nanoparticles

    Directory of Open Access Journals (Sweden)

    Xavier Jolly

    2018-01-01

    Full Text Available Nanophotonic device building blocks, such as optical nano/microcavities and plasmonic nanostructures, lie at the forefront of sensing and spectrometry of trace biological and chemical substances. A new class of nanophotonic architecture has emerged by combining optically resonant dielectric nano/microcavities with plasmonically resonant metal nanostructures to enable detection at the nanoscale with extraordinary sensitivity. Initial demonstrations include single-molecule detection and even single-ion sensing. The coupled photonic-plasmonic resonator system promises a leap forward in the nanoscale analysis of physical, chemical, and biological entities. These optoplasmonic sensor structures could be the centrepiece of miniaturised analytical laboratories, on a chip, with detection capabilities that are beyond the current state of the art. In this paper, we review this burgeoning field of optoplasmonic biosensors. We first focus on the state of the art in nanoplasmonic sensor structures, high quality factor optical microcavities, and photonic crystals separately before proceeding to an outline of the most recent advances in hybrid sensor systems. We discuss the physics of this modality in brief and each of its underlying parts, then the prospects as well as challenges when integrating dielectric nano/microcavities with metal nanostructures. In Section 5, we hint to possible future applications of optoplasmonic sensing platforms which offer many degrees of freedom towards biomedical diagnostics at the level of single molecules.

  17. Plasmonic Gold Nanorod Dispersions with Electrical and Optical Tunability

    Science.gov (United States)

    Grabowski, Christopher; Mahoney, Clare; Park, Kyoungweon; Jawaid, Ali; White, Timothy; Vaia, Richard

    The transmissive, absorptive, electrical, and thermal properties of plasmonic gold nanorods (NRs) have led to their employment in a broad range of applications. These electro-optical properties - governed by their size, shape, and composition - are widely and precisely tunable during synthesis. Gold NRs show promise for large scale optical elements as they have been demonstrated to align faster than liquid crystal films (μs) at low fields (1 V/ μm). Successfully dispersing a high volume fraction of gold NRs requires a strategy to control particle-particle separation and thus avoid aggregation. Herein, we discuss the role of theta temperature and the ability to swell or collapse the chains of polymer-grafted gold NRs to alter the interaction potential between particles. UV-Vis spectroscopy, scattering, and electrical susceptibility characterization methods were employed to determine nanoparticle dispersion along with the degree of gold NR alignment. The development of new agile photonic materials, controllable with both light and electric fields, will help address emerging needs in laser hardening (agile filters) and variable transmission visors.

  18. Polarization-resolved optical response of plasmonic particle-on-film nanocavities

    Science.gov (United States)

    Zhang, Q.; Li, G.-C.; Lo, T. W.; Lei, D. Y.

    2018-02-01

    Placing a metal nanoparticle atop a metal film forms a plasmonic particle-on-film nanocavity. Such a nanocavity supports strong plasmonic coupling that results in rich hybridized plasmon modes, rendering the cavity a versatile platform for exploiting a wide range of plasmon-enhanced spectroscopy applications. In this paper, we fully address the polarization-resolved, orientation-dependent far-field optical responses of plasmonic monomer- and dimer-on-film nanocavities by numerical simulations and experiments. With polarization-resolved dark-field spectroscopy, the distinct plasmon resonances of these nanocavities are clearly determined from their scattering spectra. Moreover, the radiation patterns of respective plasmon modes, which are often mixed together in common dark-field imaging, can be unambiguously resolved with our proposed quasi-multispectral imaging method. Explicitly, the radiation pattern of the monomer-on-film nanocavity gradually transitions from a solid spot in the green imaging channel to a doughnut ring in the red channel when tuning the excitation polarization from parallel to perpendicular to the sample surface. This observation holds true for the plasmonic dimer-on-film nanocavity with the dimer axis aligned in the incidence plane; when the dimer axis is normal to the incidence plane, the pattern transitions from a solid spot to a doughnut ring both in the red channel. These studies not only demonstrate a flexible polarization control over the optical responses of plasmonic particle-on-film nanostructures but also enrich the optical tool kit for far-field imaging and spectroscopy characterization of various plasmonic nanostructures.

  19. Photonic crystals with plasmonic patterns: novel type of the heterostructures for enhanced magneto-optical activity

    International Nuclear Information System (INIS)

    Khokhlov, N E; Belotelov, V I; Prokopov, A R; Shaposhnikov, A N; Berzhansky, V N; Kozhaev, M A; Andreev, S N; Zvezdin, A K; Ravishankar, Ajith P; Achanta, Venu Gopal; Bykov, D A

    2015-01-01

    A multilayer structure consisting of a magnetophotonic crystal with a rare-earth iron garnet microresonator layer and plasmonic grating deposited on it was fabricated and studied in order to combine functionalities of photonic and plasmonic crystals. The plasmonic pattern allows excitation of the hybrid plasmonic-waveguide modes localized in dielectric Bragg mirrors of the magnetophotonic crystal or waveguide modes inside its microresonator layer. These modes give rise to the additional resonances in the optical spectra of the structure and to the enhancement of the magneto-optical effects. The Faraday effect increases by about 50% at the microresonator modes while the transverse magneto-optical Kerr effect demonstrates pronounced peculiarities at both hybrid waveguide modes and microresonator modes and increases by several times with respect to the case of the bare magnetophotonic crystal without the metal grating. (paper)

  20. 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.

  1. Small biomolecule immunosensing with plasmonic optical fiber grating sensor.

    Science.gov (United States)

    Ribaut, Clotilde; Voisin, Valérie; Malachovská, Viera; Dubois, Valentin; Mégret, Patrice; Wattiez, Ruddy; Caucheteur, Christophe

    2016-03-15

    This study reports on the development of a surface plasmon resonance (SPR) optical fiber biosensor based on tilted fiber Bragg grating technology for direct detection of small biomarkers of interest for lung cancer diagnosis. Since SPR principle relies on the refractive index modifications to sensitively detect mass changes at the gold coated surface, we have proposed here a comparative study in relation to the target size. Two cytokeratin 7 (CK7) samples with a molecular weight ranging from 78 kDa to 2.6 kDa, respectively CK7 full protein and CK7 peptide, have been used for label-free monitoring. This work has first consisted in the elaboration and the characterization of a robust and reproducible bioreceptor, based on antibody/antigen cross-linking. Immobilized antibodies were then utilized as binding agents to investigate the sensitivity of the biosensor towards the two CK7 antigens. Results have highlighted a very good sensitivity of the biosensor response for both samples diluted in phosphate buffer with a higher limit of detection for the larger CK7 full protein. The most groundbreaking nature of this study relies on the detection of small biomolecule CK7 peptides in buffer and in the presence of complex media such as serum, achieving a limit of detection of 0.4 nM. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. 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.

  3. Plasmonic Circuit Theory for Multiresonant Light Funneling to a Single Spatial Hot Spot.

    Science.gov (United States)

    Hughes, Tyler W; Fan, Shanhui

    2016-09-14

    We present a theoretical framework, based on plasmonic circuit models, for generating a multiresonant field intensity enhancement spectrum at a single "hot spot" in a plasmonic device. We introduce a circuit model, consisting of an array of coupled LC resonators, that directs current asymmetrically in the array, and we show that this circuit can funnel energy efficiently from each resonance to a single element. We implement the circuit model in a plasmonic nanostructure consisting of a series of metal bars of differing length, with nearest neighbor metal bars strongly coupled electromagnetically through air gaps. The resulting nanostructure resonantly traps different wavelengths of incident light in separate gap regions, yet it funnels the energy of different resonances to a common location, which is consistent with our circuit model. Our work is important for a number of applications of plasmonic nanoantennas in spectroscopy, such as in single-molecule fluorescence spectroscopy or Raman spectroscopy.

  4. Polarization-dependent plasmonic splitter based on low-loss polymer optical materials

    Science.gov (United States)

    Qian, Guang; Fu, Xing-Chang; Zhang, Li-Jiang; Liu, Yi-Ran; Zhao, Ning; Zhang, Tong

    2018-01-01

    A polarization-dependent optical beam splitter consisting of a straight long-range surface plasmon polariton (LRSPP) waveguide and an S-bend polymer waveguide was designed, fabricated and measured in this paper. At the splitting section, the two different waveguides are vertically coupled. The measurenment results show that the splitter operated in dual-channel mode at TM polarization, and single-channel mode at TE polarization. In addition, the polymer waveguide and LRSPP waveguide in the splitter exhibit low propagation loss of 0.51 dB/cm and 1.7 dB/cm, respectively. The hybrid beam splitter has wide potential applications in three dimensional (3D) multilayer photonic integrated circuits (PICs).

  5. Single-mode optical fibres

    CERN Document Server

    Cancellieri, G

    1991-01-01

    This book describes signal propagation in single-mode optical fibres for telecommunication applications. Such description is based on the analysis of field propagation, considering waveguide properties and also some of the particular characteristics of the material fibre. The book covers such recent advances as, coherent transmissions; optical amplification; MIR fibres; polarization maintaining; polarization diversity and photon counting.

  6. Control of optical properties of metal-dielectric planar plasmonic nanostructures by adjusting their architecture in the case of TiAlN/Ag system

    Science.gov (United States)

    Wainstein, D. L.; Vakhrushev, V. O.; Kovalev, A. I.

    2017-05-01

    The multilayer Ag/(Ti34Al66)N metal-insulator-metal (MIM) heterostructures with different thicknesses of individual layers varied from several to several hundred nanometers were fabricated by DC-magnetron sputtering on the surfaces of Si single crystal wafers. The coatings structure was determined by STEM. The phase composition and crystallography of individual layers were studied by X-ray diffraction. The reflection indexes were measured in the photons energies range from 1 to 5 eV, or from 1240 to 248 nm. The spectroscopy of plasmon losses and plasmon microscopy allowed us to measure the plasmons losses characteristic energies and their surface distribution. The energies of plasmons peaks and their locations are strongly depending on Ag layers thickness in the MIM nanocomposite. The surface plasmon with energy about 4 eV was observed in the middle of 20 nm Ag layer. The plasmons were localized at the metal/dielectric interface for Ag layers 5 nm and less. The reflectance spectral profiles edges positions at long and short waves are correlated with plasmons energies and features of their spatial distribution. The MIMs based on the TiAlN/Ag can find applications as optical filters, photovoltaic energy conversion devices, etc.

  7. Reflection-based fibre-optic refractive index sensor using surface plasmon resonance

    Czech Academy of Sciences Publication Activity Database

    Hlubina, P.; Kadulová, M.; Ciprian, D.; Sobota, Jaroslav

    2014-01-01

    Roč. 9, August 19 (2014), 14033:1-5 ISSN 1990-2573 R&D Projects: GA MŠk(CZ) LO1212 Keywords : surface plasmon resonance * fibre-optic sensor * spectral interrogation technique * aqueous solutions of ethanol * refractive index Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.231, year: 2014

  8. Optical enhancement effects of plasmonic nanostructures on organic photovoltaic cells

    KAUST Repository

    Park, Hui Joon; Guo, L. Jay

    2015-01-01

    .g. hundreds of nanometers). Especially, the performances of OPVs with plasmonic nanoparticles in photoactive and buffer layers and with periodic nanostructures were investigated. Furthermore, nanoimprint lithography-based nanofabrication processes that can

  9. Quantum-dot based nanothermometry in optical plasmonic recording media

    International Nuclear Information System (INIS)

    Maestro, Laura Martinez; Zhang, Qiming; Li, Xiangping; Gu, Min; Jaque, Daniel

    2014-01-01

    We report on the direct experimental determination of the temperature increment caused by laser irradiation in a optical recording media constituted by a polymeric film in which gold nanorods have been incorporated. The incorporation of CdSe quantum dots in the recording media allowed for single beam thermal reading of the on-focus temperature from a simple analysis of the two-photon excited fluorescence of quantum dots. Experimental results have been compared with numerical simulations revealing an excellent agreement and opening a promising avenue for further understanding and optimization of optical writing processes and media

  10. A plasmonic fluid with dynamically tunable optical properties

    KAUST Repository

    Bhattacharjee, Rama Ranjan; Li, Ruipeng; Esté vez, Luis Antonio; Smilgies, Detlef Matthias; Amassian, Aram; Giannelis, Emmanuel P.

    2009-01-01

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

  11. A plasmonic fluid with dynamically tunable optical properties

    KAUST Repository

    Bhattacharjee, Rama Ranjan

    2009-01-01

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

  12. Optical properties of armchair (7, 7) single walled carbon nanotubes

    International Nuclear Information System (INIS)

    Gharbavi, K.; Badehian, H.

    2015-01-01

    Full potential linearized augmented plane waves method with the generalized gradient approximation for the exchange-correlation potential was applied to calculate the optical properties of (7, 7) single walled carbon nanotubes. The both x and z directions of the incident photons were applied to estimate optical gaps, dielectric function, electron energy loss spectroscopies, optical conductivity, optical extinction, optical refractive index and optical absorption coefficient. The results predict that dielectric function, ε (ω), is anisotropic since it has higher peaks along z-direction than x-direction. The static optical refractive constant were calculated about 1.4 (z-direction) and 1.1 (x- direction). Moreover, the electron energy loss spectroscopy showed a sharp π electron plasmon peaks at about 6 eV and 5 eV for z and x-directions respectively. The calculated reflection spectra show that directions perpendicular to the tube axis have further optical reflection. Moreover, z-direction indicates higher peaks at absorption spectra in low range energies. Totally, increasing the diameter of armchair carbon nanotubes cause the optical band gap, static optical refractive constant and optical reflectivity to decrease. On the other hand, increasing the diameter cause the optical absorption and the optical conductivity to increase. Moreover, the sharp peaks being illustrated at optical spectrum are related to the 1D structure of CNTs which confirm the accuracy of the calculations

  13. Plasmonics and single-molecule detection in evaporated silver-island films

    Energy Technology Data Exchange (ETDEWEB)

    Moula, G.; Aroca, R.F. [Materials and Surface Science Group, University of Windsor, Ontario (Canada); Rodriguez-Oliveros, R.; Sanchez-Gil, J.A. [Instituto de Estructura de la Materia, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid (Spain); Albella, P. [Centro de Fisica de Materiales (CSIC-UPV/EHU) and Donostia International Physics Center (DIPC), 20018 Donostia, San Sebastian (Spain)

    2012-11-15

    The plasmonic origin of surface-enhanced Raman scattering (SERS) leads to the concept of hotspots and plasmon coupling that can be realized in the interstitial regions, or on specially engineered, silver and gold nanostructures. It is also possible to achieve spatial locations of high local field or hotspots on silver-island films (SIF) allowing single-molecule detection (SMD). When a single monomolecular layer coating the SIFs contains dye molecules dispersed in it, single-molecule impurities, (with an average of one hundred dye molecules in 1 {mu}m{sup 2}, which is the field of view of the micro-Raman system), SMD is observed as a rare statistical event. Here, the SMD results for silver-island films are presented, with the same nominal mass thickness, but differing in the localized surface plasmon resonance that is a function of the temperature of substrate during deposition. A blue-shifted plasmon can be seen as a decrease in plasmon coupling for deposition at higher temperature. A simple two-particle model for localized plasmon resonance coupling calculations, including the shape and substrate effects seems to explain the trend of observations. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. Orientational imaging of a single plasmonic nanoparticle using dark-field hyperspectral imaging

    Science.gov (United States)

    Mehta, Nishir; Mahigir, Amirreza; Veronis, Georgios; Gartia, Manas Ranjan

    2017-08-01

    Orientation of plasmonic nanostructures is an important feature in many nanoscale applications such as catalyst, biosensors DNA interactions, protein detections, hotspot of surface enhanced Raman spectroscopy (SERS), and fluorescence resonant energy transfer (FRET) experiments. However, due to diffraction limit, it is challenging to obtain the exact orientation of the nanostructure using standard optical microscope. Hyperspectral Imaging Microscopy is a state-of-the-art visualization technology that combines modern optics with hyperspectral imaging and computer system to provide the identification and quantitative spectral analysis of nano- and microscale structures. In this work, initially we use transmitted dark field imaging technique to locate single nanoparticle on a glass substrate. Then we employ hyperspectral imaging technique at the same spot to investigate orientation of single nanoparticle. No special tagging or staining of nanoparticle has been done, as more likely required in traditional microscopy techniques. Different orientations have been identified by carefully understanding and calibrating shift in spectral response from each different orientations of similar sized nanoparticles. Wavelengths recorded are between 300 nm to 900 nm. The orientations measured by hyperspectral microscopy was validated using finite difference time domain (FDTD) electrodynamics calculations and scanning electron microscopy (SEM) analysis. The combination of high resolution nanometer-scale imaging techniques and the modern numerical modeling capacities thus enables a meaningful advance in our knowledge of manipulating and fabricating shaped nanostructures. This work will advance our understanding of the behavior of small nanoparticle clusters useful for sensing, nanomedicine, and surface sciences.

  15. Bifacial DNA origami-directed discrete, three-dimensional, anisotropic plasmonic nanoarchitectures with tailored optical chirality.

    Science.gov (United States)

    Lan, Xiang; Chen, Zhong; Dai, Gaole; Lu, Xuxing; Ni, Weihai; Wang, Qiangbin

    2013-08-07

    Discrete three-dimensional (3D) plasmonic nanoarchitectures with well-defined spatial configuration and geometry have aroused increasing interest, as new optical properties may originate from plasmon resonance coupling within the nanoarchitectures. Although spherical building blocks have been successfully employed in constructing 3D plasmonic nanoarchitectures because their isotropic nature facilitates unoriented localization, it still remains challenging to assemble anisotropic building blocks into discrete and rationally tailored 3D plasmonic nanoarchitectures. Here we report the first example of discrete 3D anisotropic gold nanorod (AuNR) dimer nanoarchitectures formed using bifacial DNA origami as a template, in which the 3D spatial configuration is precisely tuned by rationally shifting the location of AuNRs on the origami template. A distinct plasmonic chiral response was experimentally observed from the discrete 3D AuNR dimer nanoarchitectures and appeared in a spatial-configuration-dependent manner. This study represents great progress in the fabrication of 3D plasmonic nanoarchitectures with tailored optical chirality.

  16. Nanoscale on-chip all-optical logic parity checker in integrated plasmonic circuits in optical communication range

    Science.gov (United States)

    Wang, Feifan; Gong, Zibo; Hu, Xiaoyong; Yang, Xiaoyu; Yang, Hong; Gong, Qihuang

    2016-01-01

    The nanoscale chip-integrated all-optical logic parity checker is an essential core component for optical computing systems and ultrahigh-speed ultrawide-band information processing chips. Unfortunately, little experimental progress has been made in development of these devices to date because of material bottleneck limitations and a lack of effective realization mechanisms. Here, we report a simple and efficient strategy for direct realization of nanoscale chip-integrated all-optical logic parity checkers in integrated plasmonic circuits in the optical communication range. The proposed parity checker consists of two-level cascaded exclusive-OR (XOR) logic gates that are realized based on the linear interference of surface plasmon polaritons propagating in the plasmonic waveguides. The parity of the number of logic 1s in the incident four-bit logic signals is determined, and the output signal is given the logic state 0 for even parity (and 1 for odd parity). Compared with previous reports, the overall device feature size is reduced by more than two orders of magnitude, while ultralow energy consumption is maintained. This work raises the possibility of realization of large-scale integrated information processing chips based on integrated plasmonic circuits, and also provides a way to overcome the intrinsic limitations of serious surface plasmon polariton losses for on-chip integration applications. PMID:27073154

  17. Nanoscale on-chip all-optical logic parity checker in integrated plasmonic circuits in optical communication range.

    Science.gov (United States)

    Wang, Feifan; Gong, Zibo; Hu, Xiaoyong; Yang, Xiaoyu; Yang, Hong; Gong, Qihuang

    2016-04-13

    The nanoscale chip-integrated all-optical logic parity checker is an essential core component for optical computing systems and ultrahigh-speed ultrawide-band information processing chips. Unfortunately, little experimental progress has been made in development of these devices to date because of material bottleneck limitations and a lack of effective realization mechanisms. Here, we report a simple and efficient strategy for direct realization of nanoscale chip-integrated all-optical logic parity checkers in integrated plasmonic circuits in the optical communication range. The proposed parity checker consists of two-level cascaded exclusive-OR (XOR) logic gates that are realized based on the linear interference of surface plasmon polaritons propagating in the plasmonic waveguides. The parity of the number of logic 1s in the incident four-bit logic signals is determined, and the output signal is given the logic state 0 for even parity (and 1 for odd parity). Compared with previous reports, the overall device feature size is reduced by more than two orders of magnitude, while ultralow energy consumption is maintained. This work raises the possibility of realization of large-scale integrated information processing chips based on integrated plasmonic circuits, and also provides a way to overcome the intrinsic limitations of serious surface plasmon polariton losses for on-chip integration applications.

  18. Plasmonic superfocusing on metallic tips for near-field optical imaging and spectroscopy

    Science.gov (United States)

    Neacsu, Catalin C.; Olmon, Rob; Berweger, Samuel; Kappus, Alexandria; Kirchner, Friedrich; Ropers, Claus; Saraf, Lax; Raschke, Markus B.

    2008-03-01

    Realization of localized light sources through nonlocal excitation is important in the context of plasmon photonics, molecular sensing, and in particular near-field optical techniques. Here, the efficient conversion of propagating surface plasmons, launched on the shaft of a scanning probe tip, into localized plasmon at the apex provides a true nanoconfined light source. Focused ion beam milling is used to generate periodic surface nanostructures on the tip shaft that allow for tailoring the plasmon excitation. Using ultrashort visible and mid-IR transients the dynamics of the propagation and subsequent scattered emission is characterized. The strong field enhancement and spatial field confinement at the apex is demonstrated studying the coupling of the tip in near-field interaction with a flat sample surface. It is used in scattering near-field spectroscopic imaging (s-SNOM) to probe surface nanostructures with spatial resolution down to 10 nm.

  19. Direct optical measurement of light coupling into planar waveguide by plasmonic nanoparticles.

    Science.gov (United States)

    Pennanen, Antti M; Toppari, J Jussi

    2013-01-14

    Coupling of light into a thin layer of high refractive index material by plasmonic nanoparticles has been widely studied for application in photovoltaic devices, such as thin-film solar cells. In numerous studies this coupling has been investigated through measurement of e.g. quantum efficiency or photocurrent enhancement. Here we present a direct optical measurement of light coupling into a waveguide by plasmonic nanoparticles. We investigate the coupling efficiency into the guided modes within the waveguide by illuminating the surface of a sample, consisting of a glass slide coated with a high refractive index planar waveguide and plasmonic nanoparticles, while directly measuring the intensity of the light emitted out of the waveguide edge. These experiments were complemented by transmittance and reflectance measurements. We show that the light coupling is strongly affected by thin-film interference, localized surface plasmon resonances of the nanoparticles and the illumination direction (front or rear).

  20. 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.

  1. Plasmonic biosensors.

    Science.gov (United States)

    Hill, Ryan T

    2015-01-01

    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 popularity of film-based SPR sensing. This review surveys the current plasmonic biosensor landscape with emphasis on the basic operating principles of each plasmonic sensing technique and the practical considerations when developing a sensing platform with the various techniques. The 'gold standard' film SPR technique is reviewed briefly, but special emphasis is devoted to the up-and-coming localized surface plasmon resonance and plasmonically coupled sensor technology. © 2014 Wiley Periodicals, Inc.

  2. Optical properties and plasmonic response of silver-gallium nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Lereu, A. L. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6123 (United States); Aix-Marseille Université, CNRS, Centrale Marseille, Institut Fresnel, UMR 7249, 13013 Marseille (France); Lemarchand, F.; Zerrad, M. [Aix-Marseille Université, CNRS, Centrale Marseille, Institut Fresnel, UMR 7249, 13013 Marseille (France); Yazdanpanah, M. [NaugaNeedles LLC, Louisville, Kentucky 40299 (United States); Passian, A., E-mail: passianan@ornl.gov [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6123 (United States); Department of Physics, University of Tennessee, Knoxville, Tennessee 37996 (United States); Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996-2200 (United States)

    2015-02-14

    Silver and gallium form an alloy Ag{sub 2}Ga via a room temperature spontaneous self-assembly that exhibits remarkable mechanical and electrical properties suitable for nanoscale measurements. However, whether photon excitation of plasmons in this emerging nanomaterial is retained or not has not been established. Here, we present a thin film formation of Ag{sub 2}Ga via a spreading-reactive process of liquid Ga on an Ag film and a characterization of its dielectric function ϵ(E) = ϵ{sub 1}(E) + iϵ{sub 2}(E) in the photon energy range 1.42 eV ≤ E < 4.2 eV. It is observed that while the plasmon damping increases, near an energy of 2.25 eV, the real part of ϵ exhibits a crossing with respect to that of Ag. Furthermore, the impact of new plasmon supporting materials is discussed and in order to enable further applications in plasmonics, the possibility of photon excitation of surface plasmons in Ag{sub 2}Ga is studied.

  3. Controlling the plasmonic surface waves of metallic nanowires by transformation optics

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yichao; Yuan, Jun; Yin, Ge; Ma, Yungui, E-mail: yungui@zju.edu.cn [State Key Laboratory of Modern Optical Instrumentation, Centre for Optical and Electromagnetic Research, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310058 (China); He, Sailing [State Key Laboratory of Modern Optical Instrumentation, Centre for Optical and Electromagnetic Research, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310058 (China); Department of Electromagnetic Engineering, School of Electrical Engineering, Royal Institute of Technology, S-100 44 Stockholm (Sweden)

    2015-07-06

    In this letter, we introduce the technique of using transformation optics to manipulate the mode states of surface plasmonic waves of metallic nanowire waveguides. As examples we apply this technique to design two optical components: a three-dimensional (3D) electromagnetic mode rotator and a mode convertor. The rotator can rotate the polarization state of the surface wave around plasmonic nanowires by arbitrarily desired angles, and the convertor can transform the surface wave modes from one to another. Full-wave simulation is performed to verify the design and efficiency of our devices. Their potential application in photonic circuits is envisioned.

  4. Designing Plasmonic Materials and Optical Metasurfaces for Light Manipulation and Optical Sensing

    Science.gov (United States)

    Chen, Wenxiang

    Metamaterials are artificial materials designed to create optical properties that do not exist in nature. They are assemblies of subwavelength structures that are tailored in size, shape, composition, and orientation to realize the desired property. Metamaterials are promising for applications in diverse areas: optical filters, lenses, holography, sensors, photodetectors, photovoltaics, photocatalysts, medical devices, and many more, because of their excellent abilities in bending, absorbing, enhancing and blocking light. However, the practical use of metamaterials is challenged by the lack of plasmonic materials with proper permittivity for different applications and the slow and expensive fabrication methods available to pattern sub-wavelength structures. We have also only touched the surface in exploring the innovative uses of metamaterials to solve world problems. In this thesis, we study the fundamental optical properties of metamaterial building blocks by designing material permittivity. We continuously tune the interparticle distance in colloidal Au nanocrystal (NC) solids via the partial ligand exchange process. Then we combine top-down nanoimprint lithography with bottom-up assembly of colloidal NCs to develop a large-area, low-cost fabrication method for subwavelength nanostructures. Via this method, we fabricate and characterize nano-antenna arrays of different sizes and demonstrate metasurface quarter wave-plates of different bandwidth, and compare their performances with simulation results. We also integrate the metasurfaces with chemically- and mechanically-responsive polymers for strong-signal sensing. In the first design, we combine ultrathin plasmonic nanorods with hydrogel to fabricate optical moisture sensors for agricultural use. In the second application, we design mechanically tunable Au grating resonances on a polydimethylsiloxane (PDMS) substrate. The dimensions of Au grating are carefully engineered to achieve a hybridized, ultrasharp, and

  5. Theory of plasmonic effects in nonlinear optics: the case of graphene

    Science.gov (United States)

    Rostami, Habib; Katsnelson, Mikhail I.; Polini, Marco; Mikhail I. Katsnelson Collaboration; Habib Rostami; Marco Polini Collaboration

    The nonlinear optical properties of two-dimensional electronic systems are beginning to attract considerable interest both in the theoretical and experimental sectors. Recent experiments on the nonlinear optical properties of graphene reveal considerably strong third harmonic generation and four-wave mixing of this single-atomic-layer electronic system. We develop a large-N theory of electron-electron interaction corrections to multi-legged Feynman diagrams describing second- and third-order nonlinear response functions. Our theory is completely general and is useful to understand all second- and third-order nonlinear effects, including harmonic generation, wave mixing, and photon drag. We apply our theoretical framework to the case of graphene, by carrying out microscopic calculations of the second- and third-order nonlinear response functions of an interacting two-dimensional gas of massless Dirac fermions. We compare our results with recent measurements, where all-optical launching of graphene plasmons has been achieved. This work was supported by Fondazione Istituto Italiano di Tecnologia, the European Union's Horizon 2020 research and innovation programme under Grant agreement No. 696656 GrapheneCore, and the ERC Advanced Grant 338957 FEMTO/NANO (M.I.K.).

  6. Theoretical Analysis of the Optical Propagation Characteristics in a Fiber-Optic Surface Plasmon Resonance Sensor

    Directory of Open Access Journals (Sweden)

    Xiaolin Zheng

    2013-06-01

    Full Text Available Surface plasmon resonance (SPR sensor is widely used for its high precision and real-time analysis. Fiber-optic SPR sensor is easy for miniaturization, so it is commonly used in the development of portable detection equipment. It can also be used for remote, real-time, and online detection. In this study, a wavelength modulation fiber-optic SPR sensor is designed, and theoretical analysis of optical propagation in the optical fiber is also done. Compared with existing methods, both the transmission of a skew ray and the influence of the chromatic dispersion are discussed. The resonance wavelength is calculated at two different cases, in which the chromatic dispersion in the fiber core is considered. According to the simulation results, a novel multi-channel fiber-optic SPR sensor is likewise designed to avoid defaults aroused by the complicated computation of the skew ray as well as the chromatic dispersion. Avoiding the impact of skew ray can do much to improve the precision of this kind of sensor.

  7. Quantum interference in plasmonic circuits.

    Science.gov (United States)

    Heeres, Reinier W; Kouwenhoven, Leo P; Zwiller, Valery

    2013-10-01

    Surface plasmon polaritons (plasmons) are a combination of light and a collective oscillation of the free electron plasma at metal/dielectric interfaces. This interaction allows subwavelength confinement of light beyond the diffraction limit inherent to dielectric structures. As a result, the intensity of the electromagnetic field is enhanced, with the possibility to increase the strength of the optical interactions between waveguides, light sources and detectors. Plasmons maintain non-classical photon statistics and preserve entanglement upon transmission through thin, patterned metallic films or weakly confining waveguides. For quantum applications, it is essential that plasmons behave as indistinguishable quantum particles. Here we report on a quantum interference experiment in a nanoscale plasmonic circuit consisting of an on-chip plasmon beamsplitter with integrated superconducting single-photon detectors to allow efficient single plasmon detection. We demonstrate a quantum-mechanical interaction between pairs of indistinguishable surface plasmons by observing Hong-Ou-Mandel (HOM) interference, a hallmark non-classical interference effect that is the basis of linear optics-based quantum computation. Our work shows that it is feasible to shrink quantum optical experiments to the nanoscale and offers a promising route towards subwavelength quantum optical networks.

  8. Coupling of single quantum emitters to plasmons propagating on mechanically etched wires

    DEFF Research Database (Denmark)

    Kumar, Shailesh; Huck, Alexander; Lu, Ying-Wei

    2013-01-01

    We demonstrate the coupling of a single nitrogen vacancy center in a nanodiamond to propagating plasmonic modes of mechanically etched silver nanowires. The mechanical etch is performed on single crystalline silver nanoplates by the tip of an atomic force microscope cantilever to produce wires...

  9. Preliminary Understanding of Surface Plasmon-Enhanced Circular Dichroism Spectroscopy by Single Particle Imaging

    Science.gov (United States)

    Zhan, Kangshu

    Monitoring chiral optical signals of biomolecules as their conformation changes is an important means to study their structures, properties, and functions. Most measurements, however, are ensemble measurements because chiral optical signals from a single biomolecule is often too weak to be detected. In this dissertation, I present my early attempts to study conformational changes of adsorbed proteins by taking advantage of the enhanced electromagnetic (EM) field around a well-designed plasmonic nanofeature. In particular, I discuss the detection of protein adsorption and denaturation on metallic nanoparticles using single particle scattering and CD spectroscopic imaging. Particles of two distinctively different sizes were compared and two different sample protein molecules were studied. A combination of experimental and computational tools was used to simulate and interpret the collected scattering and CD results. The first chapter provides a brief overview of the state-of-art research in CD spectroscopic studies at the single particle level. Three different means to make particles capable of chiral detection are discussed. Various applications beyond single particle imaging are presented to showcase the potential of the described research project, beyond our immediate goals. The second chapter describes my initial characterization of large, metallic, anisotropic nanorods and the establishment of experimental procedures used later for spectrum reconstruction, data visualization and analysis. The physical shape and structure of the particles were imaged by scanning electron microscopy (SEM), the chemical composition by energy dispersive X-ray Spectroscopy (EDS), and the optical properties by darkfield microscopy. An experimental protocol was developed to connect information collected from separate techniques for the same particle, with the aims of discovering any possible structural-property correlation. The reproducibility of the single particle imaging method was

  10. Photoelectron Energy Loss in Al(002) Revisited: Retrieval of the Single Plasmon Loss Energy Distribution by a Fourier Transform Method

    Science.gov (United States)

    Santana, Victor Mancir da Silva; David, Denis; de Almeida, Jailton Souza; Godet, Christian

    2018-06-01

    A Fourier transform (FT) algorithm is proposed to retrieve the energy loss function (ELF) of solid surfaces from experimental X-ray photoelectron spectra. The intensity measured over a broad energy range towards lower kinetic energies results from convolution of four spectral distributions: photoemission line shape, multiple plasmon loss probability, X-ray source line structure and Gaussian broadening of the photoelectron analyzer. The FT of the measured XPS spectrum, including the zero-loss peak and all inelastic scattering mechanisms, being a mathematical function of the respective FT of X-ray source, photoemission line shape, multiple plasmon loss function, and Gaussian broadening of the photoelectron analyzer, the proposed algorithm gives straightforward access to the bulk ELF and effective dielectric function of the solid, assuming identical ELF for intrinsic and extrinsic plasmon excitations. This method is applied to aluminum single crystal Al(002) where the photoemission line shape has been computed accurately beyond the Doniach-Sunjic approximation using the Mahan-Wertheim-Citrin approach which takes into account the density of states near the Fermi level; the only adjustable parameters are the singularity index and the broadening energy D (inverse hole lifetime). After correction for surface plasmon excitations, the q-averaged bulk loss function, q , of Al(002) differs from the optical value Im[- 1 / ɛ( E, q = 0)] and is well described by the Lindhard-Mermin dispersion relation. A quality criterion of the inversion algorithm is given by the capability of observing weak interband transitions close to the zero-loss peak, namely at 0.65 and 1.65 eV in ɛ( E, q) as found in optical spectra and ab initio calculations of aluminum.

  11. Photoelectron Energy Loss in Al(002) Revisited: Retrieval of the Single Plasmon Loss Energy Distribution by a Fourier Transform Method

    Science.gov (United States)

    Santana, Victor Mancir da Silva; David, Denis; de Almeida, Jailton Souza; Godet, Christian

    2018-04-01

    A Fourier transform (FT) algorithm is proposed to retrieve the energy loss function (ELF) of solid surfaces from experimental X-ray photoelectron spectra. The intensity measured over a broad energy range towards lower kinetic energies results from convolution of four spectral distributions: photoemission line shape, multiple plasmon loss probability, X-ray source line structure and Gaussian broadening of the photoelectron analyzer. The FT of the measured XPS spectrum, including the zero-loss peak and all inelastic scattering mechanisms, being a mathematical function of the respective FT of X-ray source, photoemission line shape, multiple plasmon loss function, and Gaussian broadening of the photoelectron analyzer, the proposed algorithm gives straightforward access to the bulk ELF and effective dielectric function of the solid, assuming identical ELF for intrinsic and extrinsic plasmon excitations. This method is applied to aluminum single crystal Al(002) where the photoemission line shape has been computed accurately beyond the Doniach-Sunjic approximation using the Mahan-Wertheim-Citrin approach which takes into account the density of states near the Fermi level; the only adjustable parameters are the singularity index and the broadening energy D (inverse hole lifetime). After correction for surface plasmon excitations, the q-averaged bulk loss function, q , of Al(002) differs from the optical value Im[- 1 / ɛ(E, q = 0)] and is well described by the Lindhard-Mermin dispersion relation. A quality criterion of the inversion algorithm is given by the capability of observing weak interband transitions close to the zero-loss peak, namely at 0.65 and 1.65 eV in ɛ(E, q) as found in optical spectra and ab initio calculations of aluminum.

  12. Influence of the flip-flop interaction on a single plasmon transport in 1D waveguide

    Science.gov (United States)

    Ko, Myong-Chol; Kim, Nam-Chol; Ho, Nam-Chol; Ryom, Ju-Song; Hao, Zhong-Hua; Li, Jian-Bo; Wang, Qu-Quan

    2017-12-01

    Transport of a single plasmon in the 1D waveguide coupled to two emitters with the flip-flop interaction is discussed theoretically via the real-space approach. We showed that the transmission and reflection of a single plasmon could be changeable by adjusting the flip-flop coupling strength of the QDs, the interaction of QDs with the metallic nanowaveguide, interparticle distance of the QDs and detuning. Setting the interparticle distances properly results in the switching between the complete transmission and the complete reflection. Especially, our results show that the QDs with the flip-flop interaction play important role in the transport of the propagating single plasmon, which is relevant to the Förster resonance energy transfer from donor QD to acceptor QD.

  13. Alpha-fetoprotein detection by using a localized surface plasmon coupled fluorescence fiber-optic biosensor

    Science.gov (United States)

    Chang, Ying-Feng; Chen, Ran-Chou; Li, Ying-Chang; Yu, Chih-Jen; Hsieh, Bao-Yu; Chou, Chien

    2007-11-01

    Alpha-fetoprotein (AFP) detection by using a localized surface plasmon coupled fluorescence (LSPCF) fiber-optic biosensor is setup and experimentally demonstrated. It is based on gold nanoparticle (GNP) and coupled with localized surface plasmon wave on the surface of GNP. In this experiment, the fluorophores are labeled on anti-AFP which are bound to protein A conjugated GNP. Thus, LSPCF is excited with high efficiency in the near field of localized surface plasmon wave. Therefore, not only the sensitivity of LSPCF biosensor is enhanced but also the specific selectivity of AFP is improved. Experimentally, the ability of real time measurement in the range of AFP concentration from 0.1ng/ml to 100ng/ml was detected. To compare with conventional methods such as enzyme-linked immunosorbent assay (ELISA) or radioimmunoassay (RIA), the LSPCF fiber-optic biosensor performs higher or comparable detection sensitivity, respectively.

  14. 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.

  15. TiO2 brookite nanostructured thin layer on magneto-optical surface plasmon resonance transductor for gas sensing applications

    Science.gov (United States)

    Manera, M. G.; Colombelli, A.; Rella, R.; Caricato, A.; Cozzoli, P. D.; Martino, M.; Vasanelli, L.

    2012-09-01

    The sensing performance comparisons presented in this work were carried out by exploiting a suitable magneto-plasmonic sensor in both the traditional surface plasmon resonance configuration and the innovative magneto-optic surface plasmon resonance one. The particular multilayer transducer was functionalized with TiO2 Brookite nanorods layers deposited by matrix assisted pulsed laser evaporation, and its sensing capabilities were monitored in a controlled atmosphere towards different concentrations of volatile organic compounds mixed in dry air.

  16. Ultracompact all-optical full-adder and half-adder based on nonlinear plasmonic nanocavities

    Directory of Open Access Journals (Sweden)

    Xie Jingya

    2017-06-01

    Full Text Available Ultracompact chip-integrated all-optical half- and full-adders are realized based on signal-light induced plasmonic-nanocavity-modes shift in a planar plasmonic microstructure covered with a nonlinear nanocomposite layer, which can be directly integrated into plasmonic circuits. Tremendous nonlinear enhancement is obtained for the nanocomposite cover layer, attributed to resonant excitation, slow light effect, as well as field enhancement effect provided by the plasmonic nanocavity. The feature size of the device is <15 μm, which is reduced by three orders of magnitude compared with previous reports. The operating threshold power is determined to be 300 μW (corresponding to a threshold intensity of 7.8 MW/cm2, which is reduced by two orders of magnitude compared with previous reports. The intensity contrast ratio between two output logic states, “1” and “0,” is larger than 27 dB, which is among the highest values reported to date. Our work is the first to experimentally realize on-chip half- and full-adders based on nonlinear plasmonic nanocavities having an ultrasmall feature size, ultralow threshold power, and high intensity contrast ratio simultaneously. This work not only provides a platform for the study of nonlinear optics, but also paves a way to realize ultrahigh-speed signal computing chips.

  17. Analysis of Plasmonics Based Fiber Optic Sensing Structures

    Science.gov (United States)

    Moayyed, Hamed

    The work described in this PhD Thesis focuses on the post-processing of optical fibers and their enhancement as sensing element. Since the majority of sensors presented are based in Fabry-Perot interferometers, an historical overview of this category of optical fiber sensors is firstly presented. This review considers the works published since the early years, in the beginning of the 1980s, until the middle of 2015. The incorporation of microcavities at the tip of a single mode fiber was extensively studied, particularly for the measurement of nitrogen and methane gas pressure. These cavities were fabricated using hollow core silica tubes and a hollow core photonic crystal fiber. Following a different approach, the microcavities were incorporated between two sections of single mode fiber. In this case, the low sensitivity to temperature makes these microcavities highly desirable for the measurement of strain at high temperatures. Competences in post-processing techniques such as the chemical etching and the writing of periodical structures in the fiber core by means of an excimer or a femtosecond laser were also acquired in the course of the PhD programme. One of the works consisted in the design and manufacturing of a double clad optical fiber. The refractive index of the inner cladding was higher than the one of the outer cladding and the core. Thus, light was guided in the inner cladding instead of propagating in the core. This situation was overcome by applying chemical etching, thus removing the inner cladding. The core, surrounded by air, was then able to guide light. Two different applications were found for this fiber, as a temperature sensor and as an optical refractometer. In the last, the optical phase changes with the liquid refractive index. Two different types of fiber Bragg gratings were characterized in strain and temperature. Sensing structures obtained through the phase mask technique at the tip of an optical fiber were subjected to chemical

  18. Theoretical analysis of a fiber optic surface plasmon resonance sensor utilizing a Bragg grating

    Czech Academy of Sciences Publication Activity Database

    Špačková, Barbora; Homola, Jiří

    2009-01-01

    Roč. 17, č. 25 (2009), s. 23254-23264 ISSN 1094-4087 Institutional research plan: CEZ:AV0Z20670512 Keywords : Surface plasmon resonance * Fiber optic * Bragg grating * Biosensor * Coupled mode theory Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 3.278, year: 2009

  19. Novel concept of multi-channel fiber optic surface plasmon resonance sensor

    Czech Academy of Sciences Publication Activity Database

    Špačková, Barbora; Piliarik, Marek; Kvasnička, Pavel; Rajarajan, M.; Homola, Jiří

    2009-01-01

    Roč. 139, č. 1 (2009), s. 199-203 ISSN 0925-4005 R&D Projects: GA AV ČR KAN200670701 Institutional research plan: CEZ:AV0Z20670512 Keywords : . Surface plasmon resonance * Fiber optic * Bragg grating * Biosensor Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 3.083, year: 2009

  20. Polarization Control with Plasmonic Antenna Tips: A Universal Approach to Optical Nanocrystallography and Vector-Field Imaging

    Science.gov (United States)

    Park, Kyoung-Duck; Raschke, Markus B.

    2018-05-01

    Controlling the propagation and polarization vectors in linear and nonlinear optical spectroscopy enables to probe the anisotropy of optical responses providing structural symmetry selective contrast in optical imaging. Here we present a novel tilted antenna-tip approach to control the optical vector-field by breaking the axial symmetry of the nano-probe in tip-enhanced near-field microscopy. This gives rise to a localized plasmonic antenna effect with significantly enhanced optical field vectors with control of both \\textit{in-plane} and \\textit{out-of-plane} components. We use the resulting vector-field specificity in the symmetry selective nonlinear optical response of second-harmonic generation (SHG) for a generalized approach to optical nano-crystallography and -imaging. In tip-enhanced SHG imaging of monolayer MoS$_2$ films and single-crystalline ferroelectric YMnO$_3$, we reveal nano-crystallographic details of domain boundaries and domain topology with enhanced sensitivity and nanoscale spatial resolution. The approach is applicable to any anisotropic linear and nonlinear optical response, and provides for optical nano-crystallographic imaging of molecular or quantum materials.

  1. [INVITED] Surface plasmon cavities on optical fiber end-facets for biomolecule and ultrasound detection

    Science.gov (United States)

    Yang, Tian; He, Xiaolong; Zhou, Xin; Lei, Zeyu; Wang, Yalin; Yang, Jie; Cai, De; Chen, Sung-Liang; Wang, Xueding

    2018-05-01

    Integrating surface plasmon resonance (SPR) devices upon single-mode fiber (SMF) end facets renders label-free sensing systems that have a simple dip-and-read configuration, a small form factor, high compatibility with fiber-optic techniques, and invasive testing capability. Such devices are not only low cost replacement of current equipments in centralized laboratories, but also highly desirable for opening paths to new applications of label-free optical sensing technologies, such as point-of-care immunological tests and intravascular ultrasound imaging. In this paper, we explain the requirements and challenges for such devices from the perspectives of biomolecule and ultrasound detection applications. In such a context, we review our recent work on SMF end-facet SPR cavities. This include a glue-and-strip fabrication method to transfer a nano-patterned thin gold film to the SMF end-facet with high yield, high quality and high alignment precision, the designs of distributed Bragg reflector (DBR) and distributed feedback (DFB) SPR cavities that couple efficiently with the SMF guided mode and reach quality factors of over 100, and the preliminary results for biomolecule interaction sensing and ultrasound detection. The particular advantages and potential values of these devices have been discussed, in terms of sensitivity, data reliability, reproducibility, bandwidth, etc.

  2. Optical properties of WO3 thin films using surface plasmon resonance technique

    International Nuclear Information System (INIS)

    Paliwal, Ayushi; Sharma, Anjali; Gupta, Vinay; Tomar, Monika

    2014-01-01

    Indigenously assembled surface plasmon resonance (SPR) technique has been exploited to study the thickness dependent dielectric properties of WO 3 thin films. WO 3 thin films (80 nm to 200 nm) have been deposited onto gold (Au) coated glass prism by sputtering technique. The structural, optical properties and surface morphology of the deposited WO 3 thin films were studied using X-ray diffraction, UV-visible spectrophotometer, Raman spectroscopy, and Scanning electron microscopy (SEM). XRD analysis shows that all the deposited WO 3 thin films are exhibiting preferred (020) orientation and Raman data indicates that the films possess single phase monoclinic structure. SEM images reveal the variation in grain size with increase in thickness. The SPR reflectance curves of the WO 3 /Au/prism structure were utilized to estimate the dielectric properties of WO 3 thin films at optical frequency (λ = 633 nm). As the thickness of WO 3 thin film increases from 80 nm to 200 nm, the dielectric constant is seen to be decreasing from 5.76 to 3.42, while the dielectric loss reduces from 0.098 to 0.01. The estimated value of refractive index of WO 3 film is in agreement to that obtained from UV-visible spectroscopy studies. The strong dispersion in refractive index is observed with wavelength of incident laser light

  3. Optical properties of WO{sub 3} thin films using surface plasmon resonance technique

    Energy Technology Data Exchange (ETDEWEB)

    Paliwal, Ayushi; Sharma, Anjali; Gupta, Vinay, E-mail: drguptavinay@gmail.com, E-mail: vgupta@physics.du.ac.in [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Tomar, Monika [Department of Physics, Miranda House, University of Delhi, Delhi 110007 (India)

    2014-01-28

    Indigenously assembled surface plasmon resonance (SPR) technique has been exploited to study the thickness dependent dielectric properties of WO{sub 3} thin films. WO{sub 3} thin films (80 nm to 200 nm) have been deposited onto gold (Au) coated glass prism by sputtering technique. The structural, optical properties and surface morphology of the deposited WO{sub 3} thin films were studied using X-ray diffraction, UV-visible spectrophotometer, Raman spectroscopy, and Scanning electron microscopy (SEM). XRD analysis shows that all the deposited WO{sub 3} thin films are exhibiting preferred (020) orientation and Raman data indicates that the films possess single phase monoclinic structure. SEM images reveal the variation in grain size with increase in thickness. The SPR reflectance curves of the WO{sub 3}/Au/prism structure were utilized to estimate the dielectric properties of WO{sub 3} thin films at optical frequency (λ = 633 nm). As the thickness of WO{sub 3} thin film increases from 80 nm to 200 nm, the dielectric constant is seen to be decreasing from 5.76 to 3.42, while the dielectric loss reduces from 0.098 to 0.01. The estimated value of refractive index of WO{sub 3} film is in agreement to that obtained from UV-visible spectroscopy studies. The strong dispersion in refractive index is observed with wavelength of incident laser light.

  4. Tunable optical response at the plasmon-polariton frequency in dielectric-graphene-metamaterial systems

    Science.gov (United States)

    Calvo-Velasco, D. M.; Porras-Montenegro, N.

    2018-04-01

    By using the scattering matrix formalism, it is studied the optical properties of one dimensional photonic crystals made of multiple layers of dielectric and uniaxial anisotropic single negative electric metamaterial with Drude type responses, with inclusions of graphene in between the dielectric-dielectric interfaces (DGMPC). The transmission spectra for transverse electric (TE) and magnetic (TM) polarization are presented as a function of the incidence angle, the graphene chemical potential, and the metamaterial plasma frequencies. It is found for the TM polarization the tunability of the DGMPC optical response with the graphene chemical potential, which can be observed by means of transmission or reflexion bands around the metamaterial plasmon-polariton frequency, with bandwidths depending on both the incidence angle and the metamaterial plasma frequency. Also, the transmission band is observed when losses in the metamaterial slabs are considered for finite systems. The conditions for the appearance of these bands are shown analytically. We consider this work contributes to open new possibilities to the design of photonic devices with DGMPCs.

  5. Building the Nanoplasmonics Toolbox Through Shape Modeling and Single Particle Optical Studies

    Science.gov (United States)

    Ringe, Emilie

    Interest in nanotechnology is driven by unprecedented properties tailorability, achievable by controlling particle structure and composition. Unlike bulk components, minute changes in size and shape affect the optical and electronic properties of nanoparticles. Characterization of such structure-function relationships and better understanding of structure control mechanisms is crucial to the development of applications such as plasmonic sensors and devices. The objective of the current research is thus twofold: to theoretically predict and understand how shape is controlled by synthesis conditions, and to experimentally unravel, through single particle studies, how shape, composition, size, and surrounding environment affect plasmonic properties in noble metal particles. Quantitative, predictive rules and fundamental knowledge obtained from this research contributes to the "nanoplasmonics toolbox", a library designed to provide scientists and engineers the tools to create and optimize novel nanotechnology applications. In this dissertation, single particle approaches are developed and used to unravel the effects of size, shape, substrate, aggregation state and surrounding environment on the optical response of metallic nanoparticles. Ag and Au nanocubes on different substrates are first presented, followed by the discussion of the concept of plasmon length, a universal parameter to describe plasmon energy for a variety of particle shapes and plasmon modes. Plasmonic sensing (both refractive index sensing and surface-enhanced Raman spectroscopy) and polarization effects are then studied at the single particle level. In the last two Chapters, analytical shape models based on the Wulff construction provide unique modeling tools for alloy and kinetically grown nanoparticles. The former reveals a size-dependence of the shape of small alloy particles (such as those used in catalysis) because of surface segregation, while the latter uniquely models the shape of many

  6. Plasmonic Sensors Based on Doubly-Deposited Tapered Optical Fibers

    Directory of Open Access Journals (Sweden)

    Agustín González-Cano

    2014-03-01

    Full Text Available A review of the surface plasmon resonance (SPR transducers based on tapered fibers that have been developed in the last years is presented. The devices have proved their good performance (specifically, in terms of sensitivity and their versatility and they are a very good option to be considered as basis for any kind of chemical and biological sensor. The technology has now reached its maturity and here we summarize some of the characteristics of the devices produced.

  7. Optical Biosensors Based on Plasmonic Nanostructures: A Review

    Czech Academy of Sciences Publication Activity Database

    Špačková, Barbora; Wróbel, Piotr; Bocková, Markéta; Homola, Jiří

    2016-01-01

    Roč. 104, č. 12 (2016), s. 2380-2408 ISSN 0018-9219 R&D Projects: GA ČR(CZ) GBP205/12/G118 Grant - others:AV ČR(CZ) AP1101 Program:Akademická prémie - Praemium Academiae Institutional support: RVO:67985882 Keywords : Plasmonics * Biomolecular interaction analysis * Detection of biomolecules Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 9.237, year: 2016

  8. A classical treatment of optical tunneling in plasmonic gaps: extending the quantum corrected model to practical situations

    DEFF Research Database (Denmark)

    Esteban, Rubén; Zugarramurdi, Asier; Zhang, Pu

    2015-01-01

    The optical response of plasmonic nanogaps is challenging to address when the separation between the two nanoparticles forming the gap is reduced to a few nanometers or even subnanometer distances. We have compared results of the plasmon response within different levels of approximation, and iden...

  9. Ultracompact all-optical logic gates based on nonlinear plasmonic nanocavities

    Directory of Open Access Journals (Sweden)

    Yang Xiaoyu

    2016-09-01

    Full Text Available In this study, nanoscale integrated all-optical XNOR, XOR, and NAND logic gates were realized based on all-optical tunable on-chip plasmon-induced transparency in plasmonic circuits. A large nonlinear enhancement was achieved with an organic composite cover layer based on the resonant excitation-enhancing nonlinearity effect, slow light effect, and field confinement effect provided by the plasmonic nanocavity mode, which ensured a low excitation power of 200 μW that is three orders of magnitude lower than the values in previous reports. A feature size below 600 nm was achieved, which is a one order of magnitude lower compared to previous reports. The contrast ratio between the output logic states “1” and “0” reached 29 dB, which is among the highest values reported to date. Our results not only provide an on-chip platform for the study of nonlinear and quantum optics but also open up the possibility for the realization of nanophotonic processing chips based on nonlinear plasmonics.

  10. Nonlocal plasmonic response of doped and optically pumped graphene, MoS2, and black phosphorus

    Science.gov (United States)

    Petersen, René; Pedersen, Thomas Garm; Javier García de Abajo, F.

    2017-11-01

    Plasmons in two-dimensional (2D) materials have emerged as a new source of physical phenomena and optoelectronic applications due in part to the relatively small number of charge carriers on which they are supported. Unlike conventional plasmonic materials, they possess a large Fermi wavelength, which can be comparable with the plasmon wavelength, thus leading to unusually strong nonlocal effects. Here, we study the optical response of a selection of 2D crystal layers (graphene, MoS2, and black phosphorus) with inclusion of nonlocal and thermal effects. We extensively analyze their plasmon dispersion relations and focus on the Purcell factor for the decay of an optical emitter in close proximity to the material as a way to probe nonlocal and thermal effects, with emphasis placed on the interplay between temperature and doping. The results are based on tight-binding modeling of the electronic structure combined with the random-phase approximation response function in which the temperature enters through the Fermi-Dirac electronic occupation distribution. Our study provides a route map for the exploration and exploitation of the ultrafast optical response of 2D materials.

  11. A cross-stacked plasmonic nanowire network for high-contrast femtosecond optical switching.

    Science.gov (United States)

    Lin, Yuanhai; Zhang, Xinping; Fang, Xiaohui; Liang, Shuyan

    2016-01-21

    We report an ultrafast optical switching device constructed by stacking two layers of gold nanowires into a perpendicularly crossed network, which works at a speed faster than 280 fs with an on/off modulation depth of about 22.4%. The two stacks play different roles in enhancing consistently the optical switching performance due to their different dependence on the polarization of optical electric fields. The cross-plasmon resonance based on the interaction between the perpendicularly stacked gold nanowires and its Fano-coupling with Rayleigh anomaly is the dominant mechanism for such a high-contrast optical switching device.

  12. Optical and mechanical manipulation of plasmonic hot spots on gold nanoparticle tips; Optische und mechanische Manipulation plasmonischer Heisspunkte an Goldnanopartikelspitzen

    Energy Technology Data Exchange (ETDEWEB)

    Hrelescu, Calin-Alexander

    2011-06-15

    in the present thesis hybride systems based on alternative nanoparticle morphologies were studied in view of their optical properties in order to remove extensively the known limitations and insufficiencies of the established nanoparticle systems and shapes like rod-shaped or spherical nanoparticles. Star-shaped gold nanoparticles and their special plasmonic properties are presented. By methods of the dark-field spectroscopy, the photoelectron emission spectroscopy, and scanning electron microscopy the near- and far-field properties of single nanostars and their morphologies are correlated. So the first experimental proof of the localization of optically excited hot spots on the tips of the single nanostars could be given. By suited choice of the polarization and wavelength hot spots on several or exclusively single tips of a nanostar are selectively excited and the detected plasmon resonances assigned to single nanostar tips only due to experimental data. Furthermore field amplification factors in the range of 58-79 are for the first time quantitatively determined. The high and for molecules easily accessible hot spots on the tips of the nanostars are applied in order to demonstrate the excellent amplification of the Raman scattering on the level of single nanostars. The Raman amplification factors of 10{sup 7} for the studied nanostars without use of plasmonic coupling effects mark the nanostars as important candidates for the application in complex dynamical environments. A further possibility of the use of the hot spots localized on tips offer nanopyramides. By manipulation with a scanning force microscope a positioning of the hot spots until 1 nm above the surface and on arbitrary places on a sample substrate can be reached. Nanoresonators of two nanopyramides can be mechanically fabricated in three adsorption configurations concerning the tips of the two nanoparticles directed to each other. By the mechanical change of the configuration of the nanoresonator

  13. Plasmon mediated enhancement and tuning of optical emission properties of two dimensional graphitic carbon nitride nanosheets.

    Science.gov (United States)

    Bayan, Sayan; Gogurla, Narendar; Midya, Anupam; Singha, Achintya; Ray, Samit K

    2017-12-01

    We demonstrate surface plasmon induced enhancement and tunablilty in optical emission properties of two dimensional graphitic carbon nitride (g-C 3 N 4 ) nanosheets through the attachment of gold (Au) nanoparticles. Raman spectroscopy has revealed surface enhanced Raman scattering that arises due to the combined effect of the charge transfer process and localized surface plasmon induced enhancement in electromagnetic field, both occurring at the nanoparticle-nanosheet interface. Photoluminescence studies suggest that at an optimal concentration of nanoparticles, the emission intensity can be enhanced, which is maximum within the 500-525 nm region. Further, the fabricated electroluminescent devices reveal that the emission feature can be tuned from bluish-green to red (∼160 nm shift) upon attaching Au nanoparticles. We propose that the π*→π transition in g-C 3 N 4 can trigger surface plasmon oscillation in Au, which subsequently increases the excitation process in the nanosheets and results in enhanced emission in the green region of the photoluminescence spectrum. On the other hand, electroluminescence of g-C 3 N 4 can induce plasmon oscillation more efficiently and thus can lead to red emission from Au nanoparticles through the radiative damping of particle plasmons. The influence of nanoparticle size and coverage on the emission properties of two dimensional g-C 3 N 4 , nanosheets has also been studied in detail.

  14. Waveguide-Plasmon Polaritons Enhance Transverse Magneto-Optical Kerr Effect

    Directory of Open Access Journals (Sweden)

    Lars E. Kreilkamp

    2013-11-01

    Full Text Available Magneto-optical effects in ferrimagnetic or ferromagnetic materials are usually too weak for potential applications. The transverse magneto-optical Kerr effect (TMOKE in ferromagnetic films is typically on the order of 0.1%. Here, we demonstrate experimentally the enhancement of TMOKE due to the interaction of particle plasmons in gold nanowires with a photonic waveguide consisting of magneto-optical material, where hybrid waveguide-plasmon polaritons are excited. We achieve a large TMOKE that modulates the transmitted light intensity by 1.5%, accompanied by high transparency of the system. Our concept may lead to novel devices of miniaturized photonic circuits and switches, which are controllable by an external magnetic field.

  15. Enhancement of the thermo-optical response of silver nanoparticles due to surface plasmon resonance

    Science.gov (United States)

    Hashemi Zadeh, Sakineh; Rashidi-Huyeh, Majid; Palpant, Bruno

    2017-10-01

    Owing to their remarkable optical properties, noble metals' nanoparticles are proposed for many applications. Controlling the temperature dependence of these properties may then appear to be of great relevance. In this paper, we investigate the thermo-optical properties of silver nanoparticles. Different silver nanocolloids were prepared with different surface plasmon resonance modes. The thermo-extinction spectra of the colloidal solutions were then evaluated by measuring the extinction spectra at different temperatures. This reveals a typical peak-valley profile around each surface plasmon resonance mode. Mie theory was used to study theoretically the impact of nanoparticle size on the thermo-optical properties. The results allow us to interpret properly the experimental findings.

  16. Localized surface plasmons modulated nonlinear optical processes in metal film-coupled and upconversion nanocrystals-coated nanoparticles (Conference Presentation)

    Science.gov (United States)

    Lei, Dangyuan

    2016-09-01

    In the first part of this talk, I will show our experimental investigation on the linear and nonlinear optical properties of metal film-coupled nanosphere monomers and dimers both with nanometric gaps. We have developed a new methodology - polarization resolved spectral decomposition and color decoding to "visualizing" unambiguously the spectral and radiation properties of the complex plasmonic gap modes in these hybrid nanostructures. Single-particle spectroscopic measurements indicate that these hybrid nanostructures can simultaneously enhance several nonlinear optical processes, such as second harmonic generation, two-photon absorption induced luminescence, and hyper-Raman scattering. In the second part, I will show how the polarization state of the emissions from sub-10 nm upconversion nanocrystals (UCNCs) can be modulated when they form a hybrid complex with a gold nanorod (GNR). Our single-particle scattering experiments expose how an interplay between excitation polarization and GNR orientation gives rise to an extraordinary polarized nature of the upconversion emissions from an individual hybrid nanostructure. We support our results by numerical simulations and, using Förster resonance energy transfer theory, we uncover how an overlap between the UCNC emission and GNR extinction bands as well as the mutual orientation between emission and plasmonic dipoles jointly determine the polarization state of the UC emissions.

  17. Biomimetic plasmonic color generated by the single-layer coaxial honeycomb nanostructure arrays

    Science.gov (United States)

    Zhao, Jiancun; Gao, Bo; Li, Haoyong; Yu, Xiaochang; Yang, Xiaoming; Yu, Yiting

    2017-07-01

    We proposed a periodic coaxial honeycomb nanostructure array patterned in a silver film to realize the plasmonic structural color, which was inspired from natural honeybee hives. The spectral characteristics of the structure with variant geometrical parameters are investigated by employing a finite-difference time-domain method, and the corresponding colors are thus derived by calculating XYZ tristimulus values corresponding with the transmission spectra. The study demonstrates that the suggested structure with only a single layer has high transmission, narrow full-width at half-maximum, and wide color tunability by changing geometrical parameters. Therefore, the plasmonic colors realized possess a high color brightness, saturation, as well as a wide color gamut. In addition, the strong polarization independence makes it more attractive for practical applications. These results indicate that the recommended color-generating plasmonic structure has various potential applications in highly integrated optoelectronic devices, such as color filters and high-definition displays.

  18. Surface plasmon resonance based fiber optic detection of chlorine utilizing polyvinylpyrolidone supported zinc oxide thin films.

    Science.gov (United States)

    Tabassum, Rana; Gupta, Banshi D

    2015-03-21

    A highly sensitive chlorine sensor for an aqueous medium is fabricated using an optical fiber surface plasmon resonance (OFSPR) system. An OFSPR-based chlorine sensor is designed with a multilayer-type platform by zinc oxide (ZnO) and polyvinylpyrollidone (PVP) film morphology manipulations. Among all the methodologies of transduction reported in the field of solid state chemical and biochemical sensing, our attention is focused on the Kretschmann configuration optical fiber sensing technique using the mechanism of surface plasmon resonance. The optical fiber surface plasmon resonance (SPR) chlorine sensor is developed using a multimode optical fiber with the PVP-supported ZnO film deposited over a silver-coated unclad core of the fiber. A spectral interrogation mode of operation is used to characterize the sensor. In an Ag/ZnO/PVP multilayer system, the absorption of chlorine in the vicinity of the sensing region is performed by the PVP layer and the zinc oxide layer enhances the shift in resonance wavelength. It is, experimentally, demonstrated that the SPR wavelength shifts nonlinearly towards the red side of the visible region with an increase in the chlorine concentration in an aqueous medium while the sensitivity of the sensor decreases linearly with an increase in the chlorine concentration. As the proposed sensor utilizes an optical fiber, it possesses the additional advantages of fiber such as less signal degradation, less susceptibility to electromagnetic interference, possibility of remote sensing, probe miniaturization, probe re-usability, online monitoring, small size, light weight and low cost.

  19. Quasi-D-shaped optical fiber plasmonic refractive index sensor

    Science.gov (United States)

    An, Guowen; Li, Shuguang; Wang, Haiyang; Zhang, Xuenan; Yan, Xin

    2018-03-01

    A quasi-D-shaped photonic crystal fiber plasmonic sensor with a rectangular lattice is proposed by using Au as a plasmonic layer and graphene to enhance the sensing performance. By moving the core to the edge of the fiber, a shorter polishing depth is achieved, which makes the fiber proposed have a greater mechanical strength than other common D-shaped fibers. Benefiting from the natural advantage of the rectangular lattice, the dual sensing channels make the proposed sensor show a maximum wavelength interrogation sensitivity of 3877 nm/RIU with the dynamic refractive index range from 1.33 to 1.42 and a maximum amplitude sensitivity of 1236 RIU-1 with the analyte RI = 1.41 in the visible region. The corresponding resolutions are 2.58 × 10-5 and 8.1 × 10-6 with the methods of the wavelength interrogation method and amplitude- or phase-based method. These advantages make the proposed sensor a competitive candidate for biosensing in the field of refractive index detection, such as water quality analysis, clinical medicine detection, and pharmaceutical testing.

  20. Enhanced antibody recognition with a magneto-optic surface plasmon resonance (MO-SPR) sensor.

    Science.gov (United States)

    Manera, Maria Grazia; Ferreiro-Vila, Elías; Garcia-Martin, José Miguel; Garcia-Martin, Antonio; Rella, Roberto

    2014-08-15

    A comparison between sensing performance of traditional SPR (Surface Plasmon Resonance) and magneto-optic SPR (MOSPR) transducing techniques is presented in this work. MOSPR comes from an evolution of traditional SPR platform aiming at modulating Surface Plasmon wave by the application of an external magnetic field in transverse configuration. Previous work demonstrated that, when the Plasmon resonance is excited in these structures, the external magnetic field induces a modification of the coupling of the incident light with the Surface Plasmon Polaritons (SPP). Besides, these structures can lead to an enhancement in the magneto-optical (MO) activity when the SPP is excited. This phenomenon is exploited in this work to demonstrate the possibility to use the enhanced MO signal as proper transducer signal for investigating biomolecular interactions in liquid phase. To this purpose, the transducer surface was functionalized by thiol chemistry and used for recording the binding between Bovine Serum Albumin molecules immobilized onto the surface and its complementary target. Higher sensing performance in terms of sensitivity and lower limit of detection of the MOSPR biosensor with respect to traditional SPR sensors is demonstrated. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Sub-wavelength plasmonic readout for direct linear analysis of optically tagged DNA

    Science.gov (United States)

    Varsanik, Jonathan; Teynor, William; LeBlanc, John; Clark, Heather; Krogmeier, Jeffrey; Yang, Tian; Crozier, Kenneth; Bernstein, Jonathan

    2010-02-01

    This work describes the development and fabrication of a novel nanofluidic flow-through sensing chip that utilizes a plasmonic resonator to excite fluorescent tags with sub-wavelength resolution. We cover the design of the microfluidic chip and simulation of the plasmonic resonator using Finite Difference Time Domain (FDTD) software. The fabrication methods are presented, with testing procedures and preliminary results. This research is aimed at improving the resolution limits of the Direct Linear Analysis (DLA) technique developed by US Genomics [1]. In DLA, intercalating dyes which tag a specific 8 base-pair sequence are inserted in a DNA sample. This sample is pumped though a nano-fluidic channel, where it is stretched into a linear geometry and interrogated with light which excites the fluorescent tags. The resulting sequence of optical pulses produces a characteristic "fingerprint" of the sample which uniquely identifies any sample of DNA. Plasmonic confinement of light to a 100 nm wide metallic nano-stripe enables resolution of a higher tag density compared to free space optics. Prototype devices have been fabricated and are being tested with fluorophore solutions and tagged DNA. Preliminary results show evanescent coupling to the plasmonic resonator is occurring with 0.1 micron resolution, however light scattering limits the S/N of the detector. Two methods to reduce scattered light are presented: index matching and curved waveguides.

  2. Magneto-optical response of Cu/NiFe/Cu nanostructure under surface plasmon resonance

    Energy Technology Data Exchange (ETDEWEB)

    Mahmoodi, S. [Institute of Nanoscience and Nanotechnology, University of Kashan, Kashan, 87317 (Iran, Islamic Republic of); Moradi, M., E-mail: m.moradi@kashanu.ac.ir [Institute of Nanoscience and Nanotechnology, University of Kashan, Kashan, 87317 (Iran, Islamic Republic of); Mohseni, S.M. [Department of Physics, Shahid Beheshti University, Evin, Tehran, 19839 (Iran, Islamic Republic of)

    2016-12-15

    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. - Highlights: • Large magneto-optical response in Cu/NiFe/Cu multilayer nanostructure is achieved. • Layer thickness and sequence are studied to find large transverse Kerr signal. • Hybridization of surface plasmon excitation and cavity resonance were done.

  3. Sensitive singular-phase optical detection without phase measurements with Tamm plasmons

    Science.gov (United States)

    Boriskina, Svetlana V.; Tsurimaki, Yoichiro

    2018-06-01

    Spectrally-tailored interactions of light with material interfaces offer many exciting applications in sensing, photo-detection, and optical energy conversion. In particular, complete suppression of light reflectance at select frequencies accompanied by sharp phase variations in the reflected signal forms the basis for the development of ultra-sensitive singular-phase optical detection schemes such as Brewster and surface plasmon interferometry. However, both the Brewster effect and surface-plasmon-mediated absorption on planar interfaces are limited to one polarization of the incident light and oblique excitation angles, and may have limited bandwidth dictated by the material dielectric index and plasma frequency. To alleviate these limitations, we design narrow-band super-absorbers composed of plasmonic materials embedded into dielectric photonic nanostructures with topologically-protected interfacial Tamm plasmon states. These structures have planar geometry and do not require nanopatterning to achieve perfect absorption of both polarizations of the incident light in a wide range of incident angles, including the normal incidence. Their absorption lines are tunable across a very broad spectral range via engineering of the photon bandstructure of the dielectric photonic nanostructures to achieve reversal of the geometrical phase across the interface with the plasmonic absorber. We outline the design strategy to achieve perfect absorptance in Tamm structures with dissipative losses via conjugate impedance matching. We further demonstrate via modeling how these structures can be engineered to support sharp asymmetric amplitude resonances, which can be used to improve the sensitivity of optical sensors in the amplitude-only detection scheme that does not require use of bulky and expensive ellipsometry equipment.

  4. Colloidal Plasmonic Titanium Nitride Nanoparticles: Properties and Applications

    DEFF Research Database (Denmark)

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

    2015-01-01

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

  5. CW all optical self switching in nonlinear chalcogenide nano plasmonic directional coupler

    Science.gov (United States)

    Motamed-Jahromi, Leila; Hatami, Mohsen

    2018-04-01

    In this paper we obtain the coupling coefficient of plasmonic directional coupler (PDC) made up of two parallel monolayer waveguides filled with high nonlinear chalcogenide material for TM mode in continues wave (CW) regime. In addition, we assume each waveguides acts as a perturbation to other waveguide. Four nonlinear-coupled equations are derived. Transfer distances are numerically calculated and used for deriving length of all optical switch. The length of designed switch is in the range of 10-1000 μm, and the switching power is in the range of 1-100 W/m. Obtained values are suitable for designing all optical elements in the integrated optical circuits.

  6. Chemical and Biological Sensing with a Fiber Optic Surface Plasmon Resonance Device

    Science.gov (United States)

    Shevchenko, Yanina

    Fiber biosensors have emerged as an alternative to other optical sensor platforms which utilize bulkier optical elements. Sensors manufactured using optical fiber offer considerable advantages over traditional platforms, such as simple manufacturing process, small size and possibility for in situ and remote measurements. The possibility to manufacture a compact sensor with very few optical elements and package it into a portable hand-held device makes it particularly useful in many biomedical applications. Such applications generate a growing demand for an improved understanding of how fiber sensors function as well as for sensor optimization techniques so later these devices can suit the needs of the applications they are developed for. Research presented in this thesis is focused on a development of a plasmonic fiber biosensor and its application towards biochemical sensing. The fiber sensor used in this study integrates plasmonics with tilted Bragg grating technology, creating a versatile sensing solution. Plasmonics alone is an established phenomenon that is widely employed in many sensing applications. The Bragg grating is also a well-researched optical component that has been extensively applied in telecommunication. By combining both plasmonics and Bragg gratings, it is possible to design a compact and very sensitive chemical sensor. The presented work focuses on the characterization and optimization of the fiber sensor so later it could be applied in biochemical sensing. It also explores several applications including real-time monitoring of polymer adsorption, detection of thrombin and cellular sensing. All applications are focused on studying processes that are very different in their nature and thus the various strengths of the developed sensing platform were leveraged to suit the requirements of these applications.

  7. Floating dielectric slab optical interconnection between metal-dielectric interface surface plasmon polariton waveguides.

    Science.gov (United States)

    Kang, Minsu; Park, Junghyun; Lee, Il-Min; Lee, Byoungho

    2009-01-19

    A simple and effective optical interconnection which connects two distanced single metal-dielectric interface surface plasmon waveguides by a floating dielectric slab waveguide (slab bridge) is proposed. Transmission characteristics of the suggested structure are numerically studied using rigorous coupled wave analysis, and design rules based on the study are given. In the wave-guiding part, if the slab bridge can support more than the fundamental mode, then the transmission efficiency of the interconnection shows strong periodic dependency on the length of the bridge, due to the multi-mode interference (MMI) effect. Otherwise, only small fluctuation occurs due to the Fabry-Pérot effect. In addition, light beating happens when the slab bridge is relatively short. In the wave-coupling part, on the other hand, gap-assisted transmission occurs at each overlapping region as a consequence of mode hybridization. Periodic dependency on the length of the overlap region also appears due to the MMI effect. According to these results, we propose design principles for achieving both high transmission efficiency and stability with respect to the variation of the interconnection distance, and we show how to obtain the transmission efficiency of 68.3% for the 1mm-long interconnection.

  8. 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 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......). 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....

  9. A dynamic plasmonic manipulation technique assisted by phase modulation of an incident optical vortex beam

    International Nuclear Information System (INIS)

    Yuan, G H; Wang, Q; Tan, P S; Lin, J; Yuan, X-C

    2012-01-01

    A novel phase modulation method for dynamic manipulation of surface plasmon polaritons (SPPs) with a phase engineered optical vortex (OV) beam illuminating on nanoslits is experimentally demonstrated. Because of the unique helical phase carried by an OV beam, dynamic control of SPP multiple focusing and standing wave generation is realized by changing the OV beam’s topological charge constituent with the help of a liquid-crystal spatial light modulator. Measurement of SPP distributions with near-field scanning optical microscopy showed an excellent agreement with numerical predictions. The proposed phase modulation technique for manipulating SPPs features has seemingly dynamic and reconfigurable advantages, with profound potential for development of SPP coupling, routing, multiplexing and high-resolution imaging devices on plasmonic chips. (paper)

  10. Design and implementation of optical switches based on nonlinear plasmonic ring resonators: Circular, square and octagon

    Science.gov (United States)

    Ghadrdan, Majid; Mansouri-Birjandi, Mohammad Ali

    2018-05-01

    In this paper, all-optical plasmonic switches (AOPS) based on various configurations of circular, square and octagon nonlinear plasmonic ring resonators (NPRR) were proposed and numerically investigated. Each of these configurations consisted of two metal-insulator-metal (MIM) waveguides coupled to each other by a ring resonator (RR). Nonlinear Kerr effect was used to show switching performance of the proposed NPRR. The result showed that the octagon switch structure had lower threshold power and higher transmission ratio than square and circular switch structures. The octagon switch structure had a low threshold power equal to 7.77 MW/cm2 and the high transmission ratio of approximately 0.6. Therefore, the octagon switch structure was an appropriate candidate to be applied in optical integration circuits as an AOPS.

  11. Effect of edge plasmons on the optical properties of MoS2 monolayer flakes

    DEFF Research Database (Denmark)

    Rossi, Tuomas P.; Winther, Kirsten Trøstrup; Jacobsen, Karsten Wedel

    2017-01-01

    . Thus, we observe that while an evenly-spaced edge configuration supports one-dimensional (1D) plasmon modes similar to those of an ideal 1D electron gas, the relaxed structures show mixed plasmon and single-electron excitations in the low-energy response. Our findings illustrate the sensitivity...

  12. Optical Realization of Double-Continuum Fano Interference and Coherent Control in Plasmonic Metasurfaces

    Science.gov (United States)

    Arju, Nihal; Ma, Tzuhsuan; Khanikaev, Alexander; Purtseladze, David; Shvets, Gennady

    2015-06-01

    Classical realization of a ubiquitous quantum mechanical phenomenon of double-continuum Fano interference using metasurfaces is experimentally demonstrated by engineering the near-field interaction between two bright and one dark plasmonic modes. The competition between the bright modes, one of them effectively suppressing the Fano interference for the orthogonal light polarization, is discovered. Coherent control of optical energy concentration and light absorption by the ellipticity of the incident light is theoretically predicted.

  13. Surface Plasmon Scattering in Exposed Core Optical Fiber for Enhanced Resolution Refractive Index Sensing.

    Science.gov (United States)

    Klantsataya, Elizaveta; François, Alexandre; Ebendorff-Heidepriem, Heike; Hoffmann, Peter; Monro, Tanya M

    2015-09-29

    Refractometric sensors based on optical excitation of surface plasmons on the side of an optical fiber is an established sensing architecture that has enabled laboratory demonstrations of cost effective portable devices for biological and chemical applications. Here we report a Surface Plasmon Resonance (SPR) configuration realized in an Exposed Core Microstructured Optical Fiber (ECF) capable of optimizing both sensitivity and resolution. To the best of our knowledge, this is the first demonstration of fabrication of a rough metal coating suitable for spectral interrogation of scattered plasmonic wave using chemical electroless plating technique on a 10 μm diameter exposed core of the ECF. Performance of the sensor in terms of its refractive index sensitivity and full width at half maximum (FWHM) of SPR response is compared to that achieved with an unstructured bare core fiber with 140 μm core diameter. The experimental improvement in FWHM, and therefore the detection limit, is found to be a factor of two (75 nm for ECF in comparison to 150 nm for the large core fiber). Refractive index sensitivity of 1800 nm/RIU was achieved for both fibers in the sensing range of aqueous environment (1.33-1.37) suitable for biosensing applications.

  14. Design of a compact high-speed optical modulator based on a hybrid plasmonic nanobeam cavity

    Science.gov (United States)

    Javid, Mohammad Reza; Miri, Mehdi; Zarifkar, Abbas

    2018-03-01

    A hybrid plasmonic electro-optic modulator based on a polymer-filled one dimensional photonic crystal nanobeam (1D PhCNB) cavity is proposed here. In the proposed structure the optical intensity modulation is realized by shifting the resonant wavelength of the cavity through electrically tuning the refractive index of the electro-optic polymer in the hybrid plasmonic waveguide. As a result of the subwavelength light confinement in the hybrid plasmonic waveguide and the compact footprint of the 1D PhCNB cavity, the designed modulator has the small overall footprint of 3 . 6 μm2 and the required wavelength shift can be achieved by applying very small actuating power. Three dimensional finite-difference time-domain (3D-FDTD) simulations show that the modulation depth of 10.9 dB, and insertion loss of 1.14 dB, along with very high modulation speed of 224 GHz can be achieved in the proposed modulator with very low modulation energy of 0.75 fJ/bit. A comparison between the performance parameters of the proposed modulator and those of previously reported PhCNB based modulators reveals the superior performance of the proposed structure in terms of modulation speed, energy consumption and overall footprint.

  15. Enhanced and tunable optical quantum efficiencies from plasmon bandwidth engineering in bimetallic CoAg nanoparticles

    Directory of Open Access Journals (Sweden)

    A. Malasi

    2016-10-01

    Full Text Available Plasmonic nanoparticles are amongst the most effective ways to resonantly couple optical energy into and out of nanometer sized volumes. However, controlling and/or tuning the transfer of this incident energy to the surrounding near and far field is one of the most interesting challenges in this area. Due to the dielectric properties of metallic silver (Ag, its nanoparticles have amongst the highest radiative quantum efficiencies (η, i.e., the ability to radiatively transfer the incident energy to the surrounding. Here we report the discovery that bimetallic nanoparticles of Ag made with immiscible and plasmonically weak Co metal can show comparable and/or even higher η values. The enhancement is a result of the narrowing of the plasmon bandwidth from these bimetal systems. The phenomenological explanation of this effect based on the dipolar approximation points to the reduction in radiative losses within the Ag nanoparticles when in contact with cobalt. This is also supported by a model of coupling between poor and good conductors based on the surface to volume ratio. This study presents a new type of bandwidth engineering, one based on using bimetal nanostructures, to tune and/or enhance the quality factor and quantum efficiency for near and far-field plasmonic applications.

  16. Fabrication of single-crystalline plasmonic nanostructures on transparent and flexible amorphous substrates

    Science.gov (United States)

    Mori, Tomohiro; Mori, Takeshi; Tanaka, Yasuhiro; Suzaki, Yoshifumi; Yamaguchi, Kenzo

    2017-02-01

    A new experimental technique is developed for producing a high-performance single-crystalline Ag nanostructure on transparent and flexible amorphous substrates for use in plasmonic sensors and circuit components. This technique is based on the epitaxial growth of Ag on a (001)-oriented single-crystalline NaCl substrate, which is subsequently dissolved in ultrapure water to allow the Ag film to be transferred onto a wide range of different substrates. Focused ion beam milling is then used to create an Ag nanoarray structure consisting of 200 cuboid nanoparticles with a side length of 160 nm and sharp, precise edges. This array exhibits a strong signal and a sharp peak in plasmonic properties and Raman intensity when compared with a polycrystalline Ag nanoarray.

  17. [INVITED] Recent advances in surface plasmon resonance based fiber optic chemical and biosensors utilizing bulk and nanostructures

    Science.gov (United States)

    Gupta, Banshi D.; Kant, Ravi

    2018-05-01

    Surface plasmon resonance has established itself as an immensely acclaimed and influential optical sensing tool with quintessential applications in life sciences, environmental monitoring, clinical diagnostics, pharmaceutical developments and ensuring food safety. The implementation of sensing principle of surface plasmon resonance employing an optical fiber as a substrate has concomitantly resulted in the evolution of fiber optic surface plasmon resonance as an exceptionally lucrative scaffold for chemical and biosensing applications. This perspective article outlines the contemporary studies on fiber optic sensors founded on the sensing architecture of propagating as well as localized surface plasmon resonance. An in-depth review of the prevalent analytical and surface chemical tactics involved in configuring the sensing layer over an optical fiber for the detection of various chemical and biological entities is presented. The involvement of nanomaterials as a strategic approach to enhance the sensor sensitivity is furnished concurrently providing an insight into the diverse geometrical blueprints for designing fiber optic sensing probes. Representative examples from the literature are discussed to appreciate the latest advancements in this potentially valuable research avenue. The article concludes by identifying some of the key challenges and exploring the opportunities for expanding the scope and impact of surface plasmon resonance based fiber optic sensors.

  18. Mesoscopic quantum emitters coupled to plasmonic nanostructures

    DEFF Research Database (Denmark)

    Andersen, Mads Lykke

    for the spontaneous emission of mesoscopic quantum emitters is developed. The light-matter interaction is in this model modied beyond the dipole expectancy and found to both suppress and enhance the coupling to plasmonic modes in excellent agreement with our measurements. We demonstrate that this mesoscopic effect......This thesis reports research on quantum dots coupled to dielectric and plasmonic nano-structures by way of nano-structure fabrication, optical measurements, and theoretical modeling. To study light-matter interaction, plasmonic gap waveguides with nanometer dimensions as well as samples for studies...... to allow for e- cient plasmon-based single-photon sources. Theoretical studies of coupling and propagation properties of plasmonic waveguides reveal that a high-refractive index of the medium surrounding the emitter, e.g. nGaAs = 3.5, limits the realizability of ecient plasmon-based single-photon sources...

  19. Optical Activation of Germanium Plasmonic Antennas in the Mid-Infrared

    Science.gov (United States)

    Fischer, Marco P.; Schmidt, Christian; Sakat, Emilie; Stock, Johannes; Samarelli, Antonio; Frigerio, Jacopo; Ortolani, Michele; Paul, Douglas J.; Isella, Giovanni; Leitenstorfer, Alfred; Biagioni, Paolo; Brida, Daniele

    2016-07-01

    Impulsive interband excitation with femtosecond near-infrared pulses establishes a plasma response in intrinsic germanium structures fabricated on a silicon substrate. This direct approach activates the plasmonic resonance of the Ge structures and enables their use as optical antennas up to the mid-infrared spectral range. The optical switching lasts for hundreds of picoseconds until charge recombination redshifts the plasma frequency. The full behavior of the structures is modeled by the electrodynamic response established by an electron-hole plasma in a regular array of antennas.

  20. 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.

  1. Low Intensity Post Process Tuning of Optical Properties of Polymer-Plasmonic Nanoparticle Hybrids

    Science.gov (United States)

    Mahoney, Clare; Park, Kyoungweon; Vaia, Richard

    The ability to fabricate flat optics with graded refractive indices through patterned plasmonic properties is attractive for compact photonics devices. Because simultaneous self-assembly of different nanostructures within a singular film is challenging, recent efforts have shifted towards post processing methods. For example, lasers coupled to surface plasmon resonances (SPR) can induce reshaping, but often times require intense power densities that damage the matrix. Herein, we demonstrate a lower temperature approach to nanostructure reshaping based on photo-thermal triggered local redox chemistry. Xe-lamp is shown to provide volume-conserved reshaping of gold nanrods (AuNRs) dispersed within polyvinyl alcohol . Within seconds, the aspect ratio can be reduced from 5.5 to 1 (>500 nm shift in the LSPR) while maintaining particle dispersion and alignment. Using the irradiation profile and matrix thermal diffusivity, gradient resolutions of 3 nm LSPR shift per micron are seen both spatially and through thickness. Furthermore, the polarization sensitivity of the LSPR enables polarization control in reshaping. Such scalable and energy efficient plasmonic post processes will be crucial to optical-nanocomposites into future technologies. National Academy of Sciences, NRC.

  2. Narrowband interrogation of plasmonic optical fiber biosensors based on spectral combs

    Science.gov (United States)

    González-Vila, Álvaro; Kinet, Damien; Mégret, Patrice; Caucheteur, Christophe

    2017-11-01

    Gold-coated tilted fiber Bragg gratings can probe surface Plasmon polaritons with high resolution and sensitivity. In this work, we report two configurations to interrogate such plasmonic biosensors, with the aim of providing more efficient alternatives to the widespread spectrometer-based techniques. To this aim, the interrogation is based on measuring the optical power evolution of the cladding modes with respect to surrounding refractive index changes instead of computing their wavelength shift. Both setups are composed of a broadband source and a photodiode and enable a narrowband interrogation around the cladding mode that excites the surface Plasmon resonance. The first configuration makes use of a uniform fiber Bragg grating to filter the broadband response of the source in a way that the final interrogation is based on an intensity modulation measured in transmission. The second setup uses a uniform fiber grating too, but located beyond the sensor and acting as a selective optical mirror, so the interrogation is carried out in reflection. Both configurations are compared, showing interesting differential features. The first one exhibits a very high sensitivity while the second one has an almost temperature-insensitive behavior. Hence, the choice of the most appropriate method will be driven by the requirements of the target application.

  3. Detection of single amino acid mutation in human breast cancer by disordered plasmonic self-similar chain

    KAUST Repository

    Coluccio, M. L.

    2015-09-04

    Control of the architecture and electromagnetic behavior of nanostructures offers the possibility of designing and fabricating sensors that, owing to their intrinsic behavior, provide solutions to new problems in various fields. We show detection of peptides in multicomponent mixtures derived from human samples for early diagnosis of breast cancer. The architecture of sensors is based on a matrix array where pixels constitute a plasmonic device showing a strong electric field enhancement localized in an area of a few square nanometers. The method allows detection of single point mutations in peptides composing the BRCA1 protein. The sensitivity demonstrated falls in the picomolar (10−12 M) range. The success of this approach is a result of accurate design and fabrication control. The residual roughness introduced by fabrication was taken into account in optical modeling and was a further contributing factor in plasmon localization, increasing the sensitivity and selectivity of the sensors. This methodology developed for breast cancer detection can be considered a general strategy that is applicable to various pathologies and other chemical analytical cases where complex mixtures have to be resolved in their constitutive components.

  4. Detection of single amino acid mutation in human breast cancer by disordered plasmonic self-similar chain

    KAUST Repository

    Coluccio, M. L.; Gentile, F.; Das, Gobind; Nicastri, A.; Perri, A. M.; Candeloro, P.; Perozziello, G.; Proietti Zaccaria, R.; Gongora, J. S. Totero; Alrasheed, Salma; Fratalocchi, Andrea; Limongi, Tania; Cuda, G.; Di Fabrizio, Enzo M.

    2015-01-01

    Control of the architecture and electromagnetic behavior of nanostructures offers the possibility of designing and fabricating sensors that, owing to their intrinsic behavior, provide solutions to new problems in various fields. We show detection of peptides in multicomponent mixtures derived from human samples for early diagnosis of breast cancer. The architecture of sensors is based on a matrix array where pixels constitute a plasmonic device showing a strong electric field enhancement localized in an area of a few square nanometers. The method allows detection of single point mutations in peptides composing the BRCA1 protein. The sensitivity demonstrated falls in the picomolar (10−12 M) range. The success of this approach is a result of accurate design and fabrication control. The residual roughness introduced by fabrication was taken into account in optical modeling and was a further contributing factor in plasmon localization, increasing the sensitivity and selectivity of the sensors. This methodology developed for breast cancer detection can be considered a general strategy that is applicable to various pathologies and other chemical analytical cases where complex mixtures have to be resolved in their constitutive components.

  5. Magneto-plasmonic nanoantennas: Basics and applications

    Directory of Open Access Journals (Sweden)

    Ivan S. Maksymov

    2016-11-01

    Full Text Available Plasmonic nanoantennas are a hot and rapidly expanding research field. Here we overview basic operating principles and applications of novel magneto-plasmonic nanoantennas, which are made of ferromagnetic metals and driven not only by light, but also by external magnetic fields. We demonstrate that magneto-plasmonic nanoantennas enhance the magneto-optical effects, which introduces additional degrees of freedom in the control of light at the nano-scale. This property is used in conceptually new devices such as magneto-plasmonic rulers, ultra-sensitive biosensors, one-way subwavelength waveguides and extraordinary optical transmission structures, as well as in novel biomedical imaging modalities. We also point out that in certain cases ‘non-optical’ ferromagnetic nanostructures may operate as magneto-plasmonic nanoantennas. This undesigned extra functionality capitalises on established optical characterisation techniques of magnetic nanomaterials and it may be useful for the integration of nanophotonics and nanomagnetism on a single chip.

  6. Optical power-based interrogation of plasmonic tilted fiber Bragg grating biosensors

    Science.gov (United States)

    González-Vila, Á.; Lopez-Aldaba, A.; Kinet, D.; Mégret, P.; Lopez-Amo, M.; Caucheteur, C.

    2017-04-01

    Two interrogation techniques for plasmonic tilted fiber Bragg grating sensors are reported and experimentally tested. Typical interrogation methods are usually based on tracking the wavelength shift of the most sensitive cladding mode, but for biosensing applications, spectrometer-based methods can be replaced by more efficient solutions. The proposed techniques thus rely on the measurement of the induced changes in optical power. The first one consists of a properly polarized tunable laser source set to emit at the wavelength of the sensor most sensitive mode and an optical power meter to measure the transmitted response. For the second method, a uniform fiber Bragg grating is photo-inscribed beyond the sensor in such a way that its central wavelength matches the sensor most sensitive mode, acting as an optical filter. Using a LED source, light reflected backwards by this grating is partially attenuated when passing through the sensor due to plasmon wave excitation and the power changes are quantified once again with an optical power meter. A performance analysis of the techniques is carried out and they both result competitive interrogation solutions. The work thus focuses on the development of cost-effective alternatives for monitoring this kind of biosensors in practical situations.

  7. Theory of tailorable optical response of two-dimensional arrays of plasmonic nanoparticles at dielectric interfaces.

    Science.gov (United States)

    Sikdar, Debabrata; Kornyshev, Alexei A

    2016-09-22

    Two-dimensional arrays of plasmonic nanoparticles at interfaces are promising candidates for novel optical metamaterials. Such systems materialise from 'top-down' patterning or 'bottom-up' self-assembly of nanoparticles at liquid/liquid or liquid/solid interfaces. Here, we present a comprehensive analysis of an extended effective quasi-static four-layer-stack model for the description of plasmon-resonance-enhanced optical responses of such systems. We investigate in detail the effects of the size of nanoparticles, average interparticle separation, dielectric constants of the media constituting the interface, and the nanoparticle position relative to the interface. Interesting interplays of these different factors are explored first for normally incident light. For off-normal incidence, the strong effects of the polarisation of light are found at large incident angles, which allows to dynamically tune the reflectance spectra. All the predictions of the theory are tested against full-wave simulations, proving this simplistic model to be adequate within the quasi-static limit. The model takes seconds to calculate the system's optical response and makes it easy to unravel the effect of each system parameter. This helps rapid rationalization of experimental data and understanding of the optical signals from these novel 'metamaterials', optimised for light reflection or harvesting.

  8. An Optically Controlled Microscale Elevator Using Plasmonic Janus Particles.

    Science.gov (United States)

    Nedev, Spas; Carretero-Palacios, Sol; Kühler, Paul; Lohmüller, Theobald; Urban, Alexander S; Anderson, Lindsey J E; Feldmann, Jochen

    2015-04-15

    In this article, we report how Janus particles, composed of a silica sphere with a gold half-shell, can be not only stably trapped by optical tweezers but also displaced controllably along the axis of the laser beam through a complex interplay between optical and thermal forces. Scattering forces orient the asymmetric particle, while strong absorption on the metal side induces a thermal gradient, resulting in particle motion. An increase in the laser power leads to an upward motion of the particle, while a decrease leads to a downward motion. We study this reversible axial displacement, including a hysteretic jump in the particle position that is a result of the complex pattern of a tightly focused laser beam structure above the focal plane. As a first application we simultaneously trap a spherical gold nanoparticle and show that we can control the distance between the two particles inside the trap. This photonic micron-scale "elevator" is a promising tool for thermal force studies, remote sensing, and optical and thermal micromanipulation experiments.

  9. Microfluidic device for continuous single cells analysis via Raman spectroscopy enhanced by integrated plasmonic nanodimers

    DEFF Research Database (Denmark)

    Perozziello, Gerardo; Candeloro, Patrizio; De Grazia, Antonio

    2016-01-01

    In this work a Raman flow cytometer is presented. It consists of a microfluidic device that takes advantages of the basic principles of Raman spectroscopy and flow cytometry. The microfluidic device integrates calibrated microfluidic channels-where the cells can flow one-by-one -, allowing single...... cell Raman analysis. The microfluidic channel integrates plasmonic nanodimers in a fluidic trapping region. In this way it is possible to perform Enhanced Raman Spectroscopy on single cell. These allow a label-free analysis, providing information about the biochemical content of membrane and cytoplasm...

  10. Nonlinear optical observation of coherent acoustic Dirac plasmons in thin-film topological insulators

    Science.gov (United States)

    Glinka, Yuri D.; Babakiray, Sercan; Johnson, Trent A.; Holcomb, Mikel B.; Lederman, David

    2016-09-01

    Low-energy collective electronic excitations exhibiting sound-like linear dispersion have been intensively studied both experimentally and theoretically for a long time. However, coherent acoustic plasmon modes appearing in time-domain measurements are rarely observed due to Landau damping by the single-particle continua. Here we report on the observation of coherent acoustic Dirac plasmon (CADP) modes excited in indirectly (electrostatically) opposite-surface coupled films of the topological insulator Bi2Se3. Using transient second-harmonic generation, a technique capable of independently monitoring the in-plane and out-of-plane electron dynamics in the films, the GHz-range oscillations were observed without corresponding oscillations in the transient reflectivity. These oscillations were assigned to the transverse magnetic and transverse electric guided CADP modes induced by the evanescent guided Lamb acoustic waves and remained Landau undamped due to fermion tunnelling between the opposite-surface Dirac states.

  11. Plasmonic welded single walled carbon nanotubes on monolayer graphene for sensing target protein

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jangheon; Kim, Soohyun [Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, 373-1 Guseong, Yuseong, Daejeon 305-806 (Korea, Republic of); Kim, Gi Gyu; Jung, Wonsuk, E-mail: wonsuk81@wku.ac.kr [Department of Mechanical and Automotive Engineering, Wonkwang University, Iksan, Jeonbuk 570-749 (Korea, Republic of)

    2016-05-16

    We developed plasmonic welded single walled carbon nanotubes (SWCNTs) on monolayer graphene as a biosensor to detect target antigen molecules, fc fusion protein without any treatment to generate binder groups for linker and antibody. This plasmonic welding induces atomic networks between SWCNTs as junctions containing carboxylic groups and improves the electrical sensitivity of a SWCNTs and the graphene membrane to detect target protein. We investigated generation of the atomic networks between SWCNTs by field-emission scanning electron microscopy and atomic force microscopy after plasmonic welding process. We compared the intensity ratios of D to G peaks from the Raman spectra and electrical sheet resistance of welded SWCNTs with the results of normal SWCNTs, which decreased from 0.115 to 0.086 and from 10.5 to 4.12, respectively. Additionally, we measured the drain current via source/drain voltage after binding of the antigen to the antibody molecules. This electrical sensitivity of the welded SWCNTs was 1.55 times larger than normal SWCNTs.

  12. Plasmonic graded nano-disks as nano-optical conveyor belt.

    Science.gov (United States)

    Kang, Zhiwen; Lu, Haifei; Chen, Jiajie; Chen, Kun; Xu, Fang; Ho, Ho-Pui

    2014-08-11

    We propose a plasmonic system consisting of nano-disks (NDs) with graded diameters for the realization of nano-optical conveyor belt. The system contains a couple of NDs with individual elements coded with different resonant wavelengths. By sequentially switching the wavelength and polarization of the excitation source, optically trapped target nano-particle can be transferred from one ND to another. The feasibility of such function is verified based on the three-dimensional finite-difference time-domain technique and the Maxwell stress tensor method. Our design may provide an alternative way to construct nano-optical conveyor belt with which target molecules can be delivered between trapping sites, thus enabling many on-chip optofluidic applications.

  13. An optical nanoantenna made of plasmonic chain resonators

    International Nuclear Information System (INIS)

    Lester, Marcelo; Skigin, Diana C

    2011-01-01

    We propose a novel structure that behaves like an optical antenna and converts evanescent waves into propagating waves. The system comprises metallic subwavelength cylinders distributed in a dual-period array. It is illuminated by an evanescent wave generated by total internal reflection in a close interface. For particular wavelengths, the system exhibits resonances and the inhomogeneous wave is converted into propagating waves that radiate to the far field. This effect can be controlled by varying the geometrical parameters of the structure, such as the period and the inclination angle. Therefore, the transmitted intensity can be sent to a predesigned direction. This structure could be used in highly sensitive detection devices, among other applications

  14. Optically Unraveling the Edge Chirality-Dependent Band Structure and Plasmon Damping in Graphene Edges.

    Science.gov (United States)

    Duan, Jiahua; Chen, Runkun; Cheng, Yuan; Yang, Tianzhong; Zhai, Feng; Dai, Qing; Chen, Jianing

    2018-05-01

    The nontrivial topological origin and pseudospinorial character of electron wavefunctions make edge states possess unusual electronic properties. Twenty years ago, the tight-binding model calculation predicted that zigzag termination of 2D sheets of carbon atoms have peculiar edge states, which show potential application in spintronics and modern information technologies. Although scanning probe microscopy is employed to capture this phenomenon, the experimental demonstration of its optical response remains challenging. Here, the propagating graphene plasmon provides an edge-selective polaritonic probe to directly detect and control the electronic edge state at ambient condition. Compared with armchair, the edge-band structure in the bandgap gives rise to additional optical absorption and strongly absorbed rim at zigzag edge. Furthermore, the optical conductivity is reconstructed and the anisotropic plasmon damping in graphene systems is revealed. The reported approach paves the way for detecting edge-specific phenomena in other van der Waals materials and topological insulators. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Phase dependence of optical bistability and multistability in a four-level quantum system near a plasmonic nanostructure

    International Nuclear Information System (INIS)

    Asadpour, Seyyed Hossein; Rahimpour Soleimani, H.

    2016-01-01

    The optical bistability and multistability properties of a four-level quantum system near a plasmonic nanostructure embedded in a unidirectional ring cavity are studied theoretically. Two orthogonal circularly polarized laser fields with the same frequency, different phases and electric fields amplitude are interacted by four-level quantum system. It is found that in the presence of the plasmonic nanostructure, the bistable behaviors related to one of the laser fields propagating through the unidirectional ring cavity can be modified by relative phase and amplitude control of another laser fields. Our obtained results show that the optical bistability can be converted into the optical multistability by varying the value of distance between the quantum system and the surface of the plasmonic nanostructure. Moreover, it is shown that under specific condition related to the distance, the lasing without population inversion can be obtained

  16. Phase dependence of optical bistability and multistability in a four-level quantum system near a plasmonic nanostructure

    Energy Technology Data Exchange (ETDEWEB)

    Asadpour, Seyyed Hossein; Rahimpour Soleimani, H., E-mail: Rahimpour@guilan.ac.ir [Computational Nanophysics Laboratory (CNL), Department of Physics, University of Guilan, Rasht (Iran, Islamic Republic of)

    2016-01-14

    The optical bistability and multistability properties of a four-level quantum system near a plasmonic nanostructure embedded in a unidirectional ring cavity are studied theoretically. Two orthogonal circularly polarized laser fields with the same frequency, different phases and electric fields amplitude are interacted by four-level quantum system. It is found that in the presence of the plasmonic nanostructure, the bistable behaviors related to one of the laser fields propagating through the unidirectional ring cavity can be modified by relative phase and amplitude control of another laser fields. Our obtained results show that the optical bistability can be converted into the optical multistability by varying the value of distance between the quantum system and the surface of the plasmonic nanostructure. Moreover, it is shown that under specific condition related to the distance, the lasing without population inversion can be obtained.

  17. Data Transmission and Thermo-Optic Tuning Performance of Dielectric-Loaded Plasmonic Structures Hetero-Integrated on a Silicon Chip

    DEFF Research Database (Denmark)

    Giannoulis, G.; Kalavrouziotis, D.; Apostolopoulos, D.

    2012-01-01

    We demonstrate experimental evidence of the data capture and the low-energy thermo-optic tuning credentials of dielectric-loaded plasmonic structures integrated on a silicon chip. We show 7-nm thermo-optical tuning of a plasmonic racetrack-resonator with less than 3.3 mW required electrical power...

  18. Conformal Coating of a Phase Change Material on Ordered Plasmonic Nanorod Arrays for Broadband All-Optical Switching

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Peijun; Weimer, Matthew S. [Department; Emery, Jonathan D.; Diroll, Benjamin T.; Chen, Xinqi; Hock, Adam S. [Department; Chang, Robert P. H.; Martinson, Alex B. F.; Schaller, Richard D.

    2016-12-19

    Actively tunable optical transmission through artificial metamaterials holds great promise for next-generation nanophotonic devices and metasurfaces. Plasmonic nanostructures and phase change materials have been extensively studied to this end due to their respective strong interactions with light and tunable dielectric constants under external stimuli. Seamlessly integrating plasmonic components with phase change materials, as demonstrated in the present work, can facilitate phase change by plasmonically enabled light confinement and meanwhile make use of the high sensitivity of plasmon resonances to the variation of dielectric constant associated with the phase change. The hybrid platform here is composed of plasmonic indium tin-oxide nanorod arrays (ITO-NRAs) conformally coated with an ultrathin layer of a prototypical phase change material, vanadium dioxide (VO2), which enables all-optical modulation of the infrared as well as the visible spectral ranges. The interplay between the intrinsic plasmonic nonlinearity of ITO-NRAs and the phase transition induced permittivity change of VO2 gives rise to spectral and temporal responses that cannot be achieved with individual material components alone.

  19. Conformal Coating of a Phase Change Material on Ordered Plasmonic Nanorod Arrays for Broadband All-Optical Switching.

    Science.gov (United States)

    Guo, Peijun; Weimer, Matthew S; Emery, Jonathan D; Diroll, Benjamin T; Chen, Xinqi; Hock, Adam S; Chang, Robert P H; Martinson, Alex B F; Schaller, Richard D

    2017-01-24

    Actively tunable optical transmission through artificial metamaterials holds great promise for next-generation nanophotonic devices and metasurfaces. Plasmonic nanostructures and phase change materials have been extensively studied to this end due to their respective strong interactions with light and tunable dielectric constants under external stimuli. Seamlessly integrating plasmonic components with phase change materials, as demonstrated in the present work, can facilitate phase change by plasmonically enabled light confinement and meanwhile make use of the high sensitivity of plasmon resonances to the variation of dielectric constant associated with the phase change. The hybrid platform here is composed of plasmonic indium-tin-oxide nanorod arrays (ITO-NRAs) conformally coated with an ultrathin layer of a prototypical phase change material, vanadium dioxide (VO 2 ), which enables all-optical modulation of the infrared as well as the visible spectral ranges. The interplay between the intrinsic plasmonic nonlinearity of ITO-NRAs and the phase transition induced permittivity change of VO 2 gives rise to spectral and temporal responses that cannot be achieved with individual material components alone.

  20. Optically-controlled platforms for transfection and single- and sub-cellular surgery

    DEFF Research Database (Denmark)

    Villangca, Mark Jayson; Casey, Duncan; Glückstad, Jesper

    2015-01-01

    and specificity of optical trapping in conjunction with other modalities to perform single and sub-cellular surgery. These tools form highly tuneable platforms for the delivery or removal of material from cells of interest, but can simultaneously excite fluorescent probes for imaging purposes or plasmonic...... structures for very local heating. We discuss both the history and recent applications of the field, highlighting the key findings and developments over the last 40 years of biophotonics research....

  1. Simultaneous optical and electrical modeling of plasmonic light trapping in thin-film amorphous silicon photovoltaic devices

    Science.gov (United States)

    Gandhi, Keyur K.; Nejim, Ahmed; Beliatis, Michail J.; Mills, Christopher A.; Henley, Simon J.; Silva, S. Ravi P.

    2015-01-01

    Rapid prototyping of photovoltaic (PV) cells requires a method for the simultaneous simulation of the optical and electrical characteristics of the device. The development of nanomaterial-enabled PV cells only increases the complexity of such simulations. Here, we use a commercial technology computer aided design (TCAD) software, Silvaco Atlas, to design and model plasmonic gold nanoparticles integrated in optoelectronic device models of thin-film amorphous silicon (a-Si:H) PV cells. Upon illumination with incident light, we simulate the optical and electrical properties of the cell simultaneously and use the simulation to produce current-voltage (J-V) and external quantum efficiency plots. Light trapping due to light scattering and localized surface plasmon resonance interactions by the nanoparticles has resulted in the enhancement of both the optical and electrical properties due to the reduction in the recombination rates in the photoactive layer. We show that the device performance of the modeled plasmonic a-Si:H PV cells depends significantly on the position and size of the gold nanoparticles, which leads to improvements either in optical properties only, or in both optical and electrical properties. The model provides a route to optimize the device architecture by simultaneously optimizing the optical and electrical characteristics, which leads to a detailed understanding of plasmonic PV cells from a design perspective and offers an advanced tool for rapid device prototyping.

  2. Utilization of Field Enhancement in Plasmonic Waveguides for Subwavelength Light-Guiding, Polarization Handling, Heating, and Optical Sensing.

    Science.gov (United States)

    Dai, Daoxin; Wu, Hao; Zhang, Wei

    2015-10-09

    Plasmonic nanostructures have attracted intensive attention for many applications in recent years because of the field enhancement at the metal/dielectric interface. First, this strong field enhancement makes it possible to break the diffraction limit and enable subwavelength optical waveguiding, which is desired for nanophotonic integrated circuits with ultra-high integration density. Second, the field enhancement in plasmonic nanostructures occurs only for the polarization mode whose electric field is perpendicular to the metal/dielectric interface, and thus the strong birefringence is beneficial for realizing ultra-small polarization-sensitive/selective devices, including polarization beam splitters, and polarizers. Third, plasmonic nanostructures provide an excellent platform of merging electronics and photonics for some applications, e.g., thermal tuning, photo-thermal detection, etc. Finally, the field enhancement at the metal/dielectric interface helps a lot to realize optical sensors with high sensitivity when introducing plasmonic nanostrutures. In this paper, we give a review for recent progresses on the utilization of field enhancement in plasmonic nanostructures for these applications, e.g., waveguiding, polarization handling, heating, as well as optical sensing.

  3. Utilization of Field Enhancement in Plasmonic Waveguides for Subwavelength Light-Guiding, Polarization Handling, Heating, and Optical Sensing

    Directory of Open Access Journals (Sweden)

    Daoxin Dai

    2015-10-01

    Full Text Available Plasmonic nanostructures have attracted intensive attention for many applications in recent years because of the field enhancement at the metal/dielectric interface. First, this strong field enhancement makes it possible to break the diffraction limit and enable subwavelength optical waveguiding, which is desired for nanophotonic integrated circuits with ultra-high integration density. Second, the field enhancement in plasmonic nanostructures occurs only for the polarization mode whose electric field is perpendicular to the metal/dielectric interface, and thus the strong birefringence is beneficial for realizing ultra-small polarization-sensitive/selective devices, including polarization beam splitters, and polarizers. Third, plasmonic nanostructures provide an excellent platform of merging electronics and photonics for some applications, e.g., thermal tuning, photo-thermal detection, etc. Finally, the field enhancement at the metal/dielectric interface helps a lot to realize optical sensors with high sensitivity when introducing plasmonic nanostrutures. In this paper, we give a review for recent progresses on the utilization of field enhancement in plasmonic nanostructures for these applications, e.g., waveguiding, polarization handling, heating, as well as optical sensing.

  4. Electromagnetic field enhancement and spectrum shaping through plasmonically integrated optical vortices.

    Science.gov (United States)

    Ahn, Wonmi; Boriskina, Svetlana V; Hong, Yan; Reinhard, Björn M

    2012-01-11

    We introduce a new design approach for surface-enhanced Raman spectroscopy (SERS) substrates that is based on molding the optical powerflow through a sequence of coupled nanoscale optical vortices "pinned" to rationally designed plasmonic nanostructures, referred to as Vortex Nanogear Transmissions (VNTs). We fabricated VNTs composed of Au nanodiscs by electron beam lithography on quartz substrates and characterized their near- and far-field responses through combination of computational electromagnetism, and elastic and inelastic scattering spectroscopy. Pronounced dips in the far-field scattering spectra of VNTs provide experimental evidence for an efficient light trapping and circulation within the nanostructures. Furthermore, we demonstrate that VNT integration into periodic arrays of Au nanoparticles facilitates the generation of high E-field enhancements in the VNTs at multiple defined wavelengths. We show that spectrum shaping in nested VNT structures is achieved through an electromagnetic feed-mechanism driven by the coherent multiple scattering in the plasmonic arrays and that this process can be rationally controlled by tuning the array period. The ability to generate high E-field enhancements at predefined locations and frequencies makes nested VNTs interesting substrates for challenging SERS applications. © 2011 American Chemical Society

  5. Picomolar selective detection of mercuric ion (Hg{sup 2+}) using a functionalized single plasmonic gold nanoparticle

    Energy Technology Data Exchange (ETDEWEB)

    Song, Hyeon Don; Choi, Inhee; Yang, Young In; Hong, Surin; Lee, Suseung; Yi, Jongheop [School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul 151-742 (Korea, Republic of); Kang, Taewook, E-mail: xinly601@snu.ac.kr, E-mail: iniini79@snu.ac.kr, E-mail: netmo00@snu.ac.kr, E-mail: pell2004@snu.ac.kr, E-mail: jazz1863@snu.ac.kr, E-mail: twkang@sogang.ac.kr, E-mail: jyi@snu.ac.kr [Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 121-742 (Korea, Republic of)

    2010-04-09

    A highly sensitive method for the selective detection and quantification of mercuric ions (Hg{sup 2+}) using single plasmonic gold nanoparticle (GNP)-based dark-field microspectroscopy (DFMS) is demonstrated. The method is based on the scattering property of a single GNP that is functionalized with thiolated molecules, which is altered when analytes bind to the functionalized GNP. The spectral resolution of the system is 0.26 nm and a linear response to Hg{sup 2+} was found in the dynamic range of 100 pM-10 {mu}M. The method permits Hg{sup 2+} to be detected at the picomolar level, which is a remarkable reduction in the detection limit, considering the currently proscribed Environmental Protection Agency regulation level (10 nM, or 2 ppb) and the detection limits of other optical methods for detecting Hg{sup 2+} (recently approx. 1-10 nM). In addition, Hg{sup 2+} can be sensitively detected in the presence of Cd{sup 2+}, Pb{sup 2+}, Cu{sup 2+}, Zn{sup 2+} and Ni{sup 2+}, which do not interfere with the analysis. Based on the findings reported herein, it is likely that single-nanoparticle-based metal ion sensing can be extended to the development of other chemo- and biosensors for the direct detection of specific targets in an intracellular environment as well as in environmental monitoring.

  6. Roadmap on plasmonics

    Science.gov (United States)

    Stockman, Mark I.; Kneipp, Katrin; Bozhevolnyi, Sergey I.; Saha, Soham; Dutta, Aveek; Ndukaife, Justus; Kinsey, Nathaniel; Reddy, Harsha; Guler, Urcan; Shalaev, Vladimir M.; Boltasseva, Alexandra; Gholipour, Behrad; Krishnamoorthy, Harish N. S.; MacDonald, Kevin F.; Soci, Cesare; Zheludev, Nikolay I.; Savinov, Vassili; Singh, Ranjan; Groß, Petra; Lienau, Christoph; Vadai, Michal; Solomon, Michelle L.; Barton, David R., III; Lawrence, Mark; Dionne, Jennifer A.; Boriskina, Svetlana V.; Esteban, Ruben; Aizpurua, Javier; Zhang, Xiang; Yang, Sui; Wang, Danqing; Wang, Weijia; Odom, Teri W.; Accanto, Nicolò; de Roque, Pablo M.; Hancu, Ion M.; Piatkowski, Lukasz; van Hulst, Niek F.; Kling, Matthias F.

    2018-04-01

    Plasmonics is a rapidly developing field at the boundary of physical optics and condensed matter physics. It studies phenomena induced by and associated with surface plasmons—elementary polar excitations bound to surfaces and interfaces of good nanostructured metals. This Roadmap is written collectively by prominent researchers in the field of plasmonics. It encompasses selected aspects of nanoplasmonics. Among them are fundamental aspects, such as quantum plasmonics based on the quantum-mechanical properties of both the underlying materials and the plasmons themselves (such as their quantum generator, spaser), plasmonics in novel materials, ultrafast (attosecond) nanoplasmonics, etc. Selected applications of nanoplasmonics are also reflected in this Roadmap, in particular, plasmonic waveguiding, practical applications of plasmonics enabled by novel materials, thermo-plasmonics, plasmonic-induced photochemistry and photo-catalysis. This Roadmap is a concise but authoritative overview of modern plasmonics. It will be of interest to a wide audience of both fundamental physicists and chemists, as well as applied scientists and engineers.

  7. STM Imaging of Localized Surface Plasmons on Individual Gold Nanoislands.

    Science.gov (United States)

    Nguyen, Huy A; Banerjee, Progna; Nguyen, Duc; Lyding, Joseph W; Gruebele, Martin; Jain, Prashant K

    2018-04-19

    An optically modulated scanning tunneling microscopy technique developed for measurement of single-molecule optical absorption is used here to image the light absorption by individual Au nanoislands and Au nanostructures. The technique is shown to spatially map, with nanometer resolution, localized surface plasmons (LSPs) excited within the nanoislands. Electrodynamic simulations demonstrate the correspondence of the measured images to plasmonic near-field intensity maps. The optical STM imaging technique captures the wavelength, polarization, and geometry dependence of the LSP resonances and their corresponding near-fields. Thus, we introduce a tool for real-space, nanometer-scale visualization of optical energy absorption, transport, and dissipation in complex plasmonic nanostructures.

  8. Integrated optical and electrical modeling of plasmon-enhanced thin film photovoltaics: A case-study on organic devices

    International Nuclear Information System (INIS)

    Rourke, Devin; Ahn, Sungmo; Nardes, Alexandre M.; Lagemaat, Jao van de; Kopidakis, Nikos; Park, Wounjhang

    2014-01-01

    The nanoscale light control for absorption enhancement of organic photovoltaic (OPV) devices inevitably produces strongly non-uniform optical fields. These non-uniformities due to the localized optical modes are a primary route toward absorption enhancement in OPV devices. Therefore, a rigorous modeling tool taking into account the spatial distribution of optical field and carrier generation is necessary. Presented here is a comprehensive numerical model to describe the coupled optical and electrical behavior of plasmon-enhanced polymer:fullerene bulk heterojunction (BHJ) solar cells. In this model, a position-dependent electron-hole pair generation rate that could become highly non-uniform due to photonic nanostructures is directly calculated from the optical simulations. By considering the absorption and plasmonic properties of nanophotonic gratings included in two different popular device architectures, and applying the Poisson, current continuity, and drift/diffusion equations, the model predicts quantum efficiency, short-circuit current density, and desired carrier mobility ratios for bulk heterojunction devices incorporating nanostructures for light management. In particular, the model predicts a significant degradation of device performance when the carrier species with lower mobility are generated far from the collecting electrode. Consequently, an inverted device architecture is preferred for materials with low hole mobility. This is especially true for devices that include plasmonic nanostructures. Additionally, due to the incorporation of a plasmonic nanostructure, we use simulations to theoretically predict absorption band broadening of a BHJ into energies below the band gap, resulting in a 4.8% increase in generated photocurrent.

  9. Integrated optical and electrical modeling of plasmon-enhanced thin film photovoltaics: A case-study on organic devices

    Energy Technology Data Exchange (ETDEWEB)

    Rourke, Devin [Department of Physics, University of Colorado, Boulder, Colorado 80309-0390 (United States); Ahn, Sungmo [Department of Electrical, Computer, and Energy Engineering, University of Colorado, Boulder, Colorado 80309-0425 (United States); Nardes, Alexandre M.; Lagemaat, Jao van de; Kopidakis, Nikos [National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401 (United States); Park, Wounjhang, E-mail: won.park@colorado.edu [Department of Electrical, Computer, and Energy Engineering, University of Colorado, Boulder, Colorado 80309-0425 (United States); Materials Science and Engineering Program, University of Colorado, Boulder, Colorado 80303 (United States)

    2014-09-21

    The nanoscale light control for absorption enhancement of organic photovoltaic (OPV) devices inevitably produces strongly non-uniform optical fields. These non-uniformities due to the localized optical modes are a primary route toward absorption enhancement in OPV devices. Therefore, a rigorous modeling tool taking into account the spatial distribution of optical field and carrier generation is necessary. Presented here is a comprehensive numerical model to describe the coupled optical and electrical behavior of plasmon-enhanced polymer:fullerene bulk heterojunction (BHJ) solar cells. In this model, a position-dependent electron-hole pair generation rate that could become highly non-uniform due to photonic nanostructures is directly calculated from the optical simulations. By considering the absorption and plasmonic properties of nanophotonic gratings included in two different popular device architectures, and applying the Poisson, current continuity, and drift/diffusion equations, the model predicts quantum efficiency, short-circuit current density, and desired carrier mobility ratios for bulk heterojunction devices incorporating nanostructures for light management. In particular, the model predicts a significant degradation of device performance when the carrier species with lower mobility are generated far from the collecting electrode. Consequently, an inverted device architecture is preferred for materials with low hole mobility. This is especially true for devices that include plasmonic nanostructures. Additionally, due to the incorporation of a plasmonic nanostructure, we use simulations to theoretically predict absorption band broadening of a BHJ into energies below the band gap, resulting in a 4.8% increase in generated photocurrent.

  10. All-optical bistable logic control based on coupled Tamm plasmons.

    Science.gov (United States)

    Zhang, Wei Li; Jiang, Yao; Zhu, Ye Yu; Wang, Fen; Rao, Yun Jiang

    2013-10-15

    A method for realizing low-threshold all-optical bistable logic control is proposed based on Tamm plasmons (TPs), which are formed in an asymmetric dielectric Bragg reflector (DBR)-metal-DBR (ADMD) structure with a layer of Kerr medium embedded. The ADMD structure supports two TPs due to coupling of trapped modes at each metal-DBR interface, generating two dips in the structure's reflection spectrum. Thus, control (i.e., pump) and controlled (i.e., probe) light with wavelengths close to the two dips, respectively, can be imported. It is verified theoretically that, thanks to the enhanced Kerr nonlinearity related to excitation of high-quality TP, bistable switching at very low injection intensity can be initiated by strength or direction variation of the pump. Meanwhile, the probe changes correspondingly with the pump. Thus, all-optical bistable logic operation of the probe can be controlled by the pump.

  11. Plasmonic gold nanostars as optical nano-additives for injection molded polymer composites

    Science.gov (United States)

    Boyne, Devon A.; Orlicki, Joshua A.; Walck, Scott D.; Savage, Alice M.; Li, Thomas; Griep, Mark H.

    2017-10-01

    Nanoscale engineering of noble metal particles has provided numerous material configurations to selectively confine and manipulate light across the electromagnetic spectrum. Transitioning these materials to a composite form while maintaining the desired resonance properties has proven challenging. In this work, the successful integration of plasmon-focusing gold nanostars (GNSs) into polymer nanocomposites (PNCs) is demonstrated. Tailored GNSs are produced with over a 90% yield and methods to control the branching structures are shown. A protective silica capping shell is employed on the nanomaterials to facilitate survivability in the high temperate/high shear processing parameters to create optically-tuned injection molded PNCs. The developed GNS PNCs possess dichroic scattering and absorption behavior, opening up potential applications in the fields of holographic imaging, optical filtering and photovoltaics.

  12. Optical Properties of Complex Plasmonic Materials Studied with Extended Effective Medium Theories Combined with Rigorous Coupled Wave Analysis

    Directory of Open Access Journals (Sweden)

    Elie Nadal

    2018-02-01

    Full Text Available In this study we fabricate gold nanocomposites and model their optical properties. The nanocomposites are either homogeneous films or gratings containing gold nanoparticles embedded in a polymer matrix. The samples are fabricated using a recently developed technique making use of laser interferometry. The gratings present original plasmon-enhanced diffraction properties. In this work, we develop a new approach to model the optical properties of our composites. We combine the extended Maxwell–Garnett model of effective media with the Rigorous Coupled Wave Analysis (RCWA method and compute both the absorption spectra and the diffraction efficiency spectra of the gratings. We show that such a semi-analytical approach allows us to reproduce the original plasmonic features of the composites and can provide us with details about their inner structure. Such an approach, considering reasonably high particle concentrations, could be a simple and efficient tool to study complex micro-structured system based on plasmonic components, such as metamaterials.

  13. E-beam deposited Ag-nanoparticles plasmonic organic solar cell and its absorption enhancement analysis using FDTD-based cylindrical nano-particle optical model.

    Science.gov (United States)

    Kim, Richard S; Zhu, Jinfeng; Park, Jeung Hun; Li, Lu; Yu, Zhibin; Shen, Huajun; Xue, Mei; Wang, Kang L; Park, Gyechoon; Anderson, Timothy J; Pei, Qibing

    2012-06-04

    We report the plasmon-assisted photocurrent enhancement in Ag-nanoparticles (Ag-NPs) embedded PEDOT:PSS/P3HT:PCBM organic solar cells, and systematically investigate the causes of the improved optical absorption based on a cylindrical Ag-NPs optical model which is simulated with a 3-Dimensional finite difference time domain (FDTD) method. The proposed cylindrical Ag-NPs optical model is able to explain the optical absorption enhancement by the localized surface plasmon resonance (LSPR) modes, and to provide a further understanding of Ag-NPs shape parameters which play an important role to determine the broadband absorption phenomena in plasmonic organic solar cells. A significant increase in the power conversion efficiency (PCE) of the plasmonic solar cell was experimentally observed and compared with that of the solar cells without Ag-NPs. Finally, our conclusion was made after briefly discussing the electrical effects of the fabricated plasmonic organic solar cells.

  14. Single spin stochastic optical reconstruction microscopy

    OpenAIRE

    Pfender, Matthias; Aslam, Nabeel; Waldherr, Gerald; Wrachtrup, Jörg

    2014-01-01

    We experimentally demonstrate precision addressing of single quantum emitters by combined optical microscopy and spin resonance techniques. To this end we utilize nitrogen-vacancy (NV) color centers in diamond confined within a few ten nanometers as individually resolvable quantum systems. By developing a stochastic optical reconstruction microscopy (STORM) technique for NV centers we are able to simultaneously perform sub diffraction-limit imaging and optically detected spin resonance (ODMR)...

  15. Development of an optical surface plasmon resonance biosensor assay for (fluoro) quinolones in egg, fish, and poultry meat

    NARCIS (Netherlands)

    Huet, A.C.; Charlier, C.; Singh, G.; Benrejeb Godefroy, S.; Leivo, J.; Vehniainen, M.; Nielen, M.W.F.; Weigel, S.; Delahaut, P.

    2008-01-01

    The aim of this study was to develop an optical biosensor inhibition immunoassay, based on the surface plasmon resonance (SPR) principle, for use as a screening test for 13 (fluoro)quinolones, including flumequine, used as veterinary drugs in food-producing animals. For this, we immobilised various

  16. Nanoscale patterning of gold-coated optical fibers for improved plasmonic sensing

    Science.gov (United States)

    Antohe, Iulia; Spasic, Dragana; Delport, Filip; Li, Jiaqi; Lammertyn, Jeroen

    2017-05-01

    Merging surface plasmon resonance (SPR) to fiber optic (FO) technology has brought remarkable achievements in the field by offering attractive advantages over the conventional prism-based SPR platforms, such as simplicity, cost-effectiveness and miniaturization. However, the performance of the existing FO-SPR instruments mainly depends on the device surface condition and in particular on the structural aspect of the thin gold (Au) plasmonic film deposited on the FO substrate. In this work, a simple cost-effective colloidal lithography technique (CLT) was adapted and applied for the first time to the micrometer-sized FO substrate, to design end reflection-type FO-SPR sensors with periodic arrays of Au triangularly-shaped nanostructures on the Au mirror FO tip distal end. The nanopatterned FO-SPR sensor tips were afterwards subjected to refractometric measurements in a sucrose dilution series and subsequently compared with their non-patterned counterparts. It was observed that the spectral dips of the nanopatterned FO-SPR sensor tips were shifted towards longer wavelengths after CLT patterning. Moreover, the sensor sensitivity was improved with up to 25% compared to the conventional non-patterned FO-SPR devices. The obtained results represent important steps in the development of a new generation of FO-SPR sensors with improved performance, which can ultimately be used in various applications, ranging from food analysis and environmental monitoring, to health control and medical diagnosis.

  17. A Low-Cost and Portable Dual-Channel Fiber Optic Surface Plasmon Resonance System.

    Science.gov (United States)

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

    2017-12-04

    A miniaturization and integration dual-channel fiber optic surface plasmon resonance (SPR) system was proposed and demonstrated in this paper. We used a yellow light-emitting diode (LED, peak wavelength 595 nm) and built-in web camera as a light source and detector, respectively. Except for the detection channel, one of the sensors was used as a reference channel to compensate nonspecific binding and physical absorption. We packaged the LED and surface plasmon resonance (SPR) sensors together, which are flexible enough to be applied to mobile devices as a compact and portable system. Experimental results show that the normalized intensity shift and refractive index (RI) of the sample have a good linear relationship in the RI range from 1.328 to 1.348. We used this sensor to monitor the reversible, specific interaction between lectin concanavalin A (Con A) and glycoprotein ribonuclease B (RNase B), which demonstrate its capabilities of specific identification and biochemical samples concentration detection. This sensor system has potential applications in various fields, such as medical diagnosis, public health, food safety, and environment monitoring.

  18. A microfluidic device integrating plasmonic nanodevices for Raman spectroscopy analysis on trapped single living cells

    KAUST Repository

    Perozziello, Gerardo

    2013-11-01

    In this work we developed a microfluidic device integrating nanoplasmonic devices combined with fluidic trapping regions. The microfuidic traps allow to capture single cells in areas where plasmonic sensors are placed. In this way it is possible to perform Enhanced Raman analysis on the cell membranes. Moreover, by changing direction of the flux it is possible to change the orientation of the cell in the trap, so that it is possible to analyze different points of the membrane of the same cell. We shows an innovative procedure to fabricate and assembly the microfluidic device which combine photolithography, focused ion beam machining, and hybrid bonding between a polymer substrate and lid of Calcium fluoride. This procedure is compatible with the fabrication of the plasmonic sensors in close proximity of the microfluidic traps. Moreover, the use of Calcium fluoride as lid allows full compatibility with Raman measurements producing negligible Raman background signal and avoids Raman artifacts. Finally, we performed Raman analysis on cells to monitor their oxidative stress under particular non physiological conditions. © 2013 Elsevier B.V. All rights reserved.

  19. A microfluidic device integrating plasmonic nanodevices for Raman spectroscopy analysis on trapped single living cells

    KAUST Repository

    Perozziello, Gerardo; Catalano, Rossella; Francardi, Marco; Rondanina, Eliana; Pardeo, Francesca; De Angelis, Francesco De; Malara, Natalia Maria; Candeloro, Patrizio; Morrone, Giovanni; Di Fabrizio, Enzo M.

    2013-01-01

    In this work we developed a microfluidic device integrating nanoplasmonic devices combined with fluidic trapping regions. The microfuidic traps allow to capture single cells in areas where plasmonic sensors are placed. In this way it is possible to perform Enhanced Raman analysis on the cell membranes. Moreover, by changing direction of the flux it is possible to change the orientation of the cell in the trap, so that it is possible to analyze different points of the membrane of the same cell. We shows an innovative procedure to fabricate and assembly the microfluidic device which combine photolithography, focused ion beam machining, and hybrid bonding between a polymer substrate and lid of Calcium fluoride. This procedure is compatible with the fabrication of the plasmonic sensors in close proximity of the microfluidic traps. Moreover, the use of Calcium fluoride as lid allows full compatibility with Raman measurements producing negligible Raman background signal and avoids Raman artifacts. Finally, we performed Raman analysis on cells to monitor their oxidative stress under particular non physiological conditions. © 2013 Elsevier B.V. All rights reserved.

  20. On the physical contributions to the third-order nonlinear optical response in plasmonic nanocomposites

    International Nuclear Information System (INIS)

    Fernández-Hernández, Roberto Carlos; Gleason-Villagran, Roberto; Rodríguez-Fernández, Luis; Crespo-Sosa, Alejandro; Cheang-Wong, Juan Carlos; López-Suárez, Alejandra; Oliver, Alicia; Reyes-Esqueda, Jorge Alejandro; Torres-Torres, Carlos; Rangel-Rojo, Raúl

    2012-01-01

    Au and Ag isotropic and anisotropic nanocomposites were prepared using the ion implantation technique. Their optical properties were studied at several wavelengths in the optical range 300–800 nm, across their plasmon resonances. The linear regime was characterized by measuring the absorption spectrum and the third-order nonlinear regime by means of the Z-scan technique using a tunable picosecond pulsed laser system (26 ps). Open-aperture Z-scan traces show a superposition of different optical nonlinear absorption (NLA) processes in the whole range studied. We associate these phenomena with the excitation of inter- and intra-band electronic transitions, which contribute with a positive sign to NLA, and to the formation of hot-electrons, which contribute with opposite sign to NLA. Closed-aperture traces for measuring nonlinear refraction (NLR) show different signs for Au and Ag samples, and a change of sign in Au is found when purely inter-band transitions are excited. In this work, for the appropriate wavelength, it is worth remarking on the free-electron response to the exciting light and its strong contribution to the nonlinear optical properties for low (intra-band) and high (hot-electrons) irradiances. (paper)

  1. Integrated-Optics Components Utilizing Long-Range Surface Plasmon Polaritons

    DEFF Research Database (Denmark)

    Boltasseva, Alexandra

    2004-01-01

    This thesis describes a new class of components for integrated optics, based on the propagation of long-range surface plasmon polaritons (LR-SPPs) along metal stripes embedded in a dielectric. These novel components can provide guiding of light as well as coupling and splitting from/into a number...... with experimental results is obtained. The interaction of LR-SPPs with photonic crystals (PCs) is also studied. The PC structures are formed by periodic arrays of gold bumps that are arranged in a triangular lattice and placed symmetrically on both sides of a thin gold film. The LR-SPP transmission through...... of channels with good performance. Guiding of LR-SPPs along nm-thin and µm-wide gold stripes embedded in polymer is investigated in the wavelength range of 1250 – 1650 nm. LR-SPP guiding properties, such as the propagation loss and mode field diameter, are studied for different stripe widths and thicknesses...

  2. Surface plasmon resonance based optical fiber riboflavin sensor by using molecularly imprinted gel

    Science.gov (United States)

    Verma, Roli; Gupta, Banshi D.

    2013-05-01

    We report the fabrication and characterization of surface plasmon resonance (SPR) based optical fiber riboflavin/vitamin B2 sensor using combination of colloidal crystal templating and molecularly imprinted gel. The sensor works on spectral interrogation method. The operating range of the sensor lies from 0 μg/ml to 320 μg/ml, the suitable amount of intakes of riboflavin recommended for different age group. The SPR spectra show blue shift with increasing concentration of riboflavin, which is due to the interaction of riboflavin molecule over specific binding sites caused by molecular imprinting. The present sensor has many advantageous features such as fast response, small probe size, low cost and can be used for remote/online monitoring.

  3. A compact plasmonic MOS-based 2×2 electro-optic switch

    Directory of Open Access Journals (Sweden)

    Ye Chenran

    2015-01-01

    Full Text Available We report on a three-waveguide electro-optic switch for compact photonic integrated circuits and data routing applications. The device features a plasmonic metal-oxide-semiconductor (MOS mode for enhanced light-matter-interactions. The switching mechanism originates from a capacitor-like design where the refractive index of the active medium, indium-tin-oxide, is altered via shifting the plasma frequency due to carrier accumulation inside the waveguide-based MOS structure. This light manipulation mechanism controls the transmission direction of transverse magnetic polarized light into either a CROSS or BAR waveguide port. The extinction ratio of 18 (7 dB for the CROSS (BAR state, respectively, is achieved via a gating voltage bias. The ultrafast broadband fJ/bit device allows for seamless integration with silicon-on-insulator platforms for low-cost manufacturing.

  4. Active plasmonics in WDM traffic switching applications

    DEFF Research Database (Denmark)

    Papaioannou, S.; Kalavrouziotis, D.; Vyrsokinos, K.

    2012-01-01

    -enabling characteristics of active plasmonic circuits with an ultra-low power 3 response time product represents a crucial milestone in the development of active plasmonics towards real telecom and datacom applications, where low-energy and fast TO operation with small-size circuitry is targeted........ The first active Dielectric-Loaded Surface Plasmon Polariton (DLSPP) thermo-optic (TO) switches with successful performance in single-channel 10 Gb/s data traffic environments have led the inroad towards bringing low-power active plasmonics in practical traffic applications. In this article, we introduce...... active plasmonics into Wavelength Division Multiplexed (WDM) switching applications, using the smallest TO DLSPP-based Mach-Zehnder interferometric switch reported so far and showing its successful performance in 4310 Gb/s low-power and fast switching operation. The demonstration of the WDM...

  5. Modifying infrared scattering effects of single yeast cells with plasmonic metal mesh

    Science.gov (United States)

    Malone, Marvin A.; Prakash, Suraj; Heer, Joseph M.; Corwin, Lloyd D.; Cilwa, Katherine E.; Coe, James V.

    2010-11-01

    The scattering effects in the infrared (IR) spectra of single, isolated bread yeast cells (Saccharomyces cerevisiae) on a ZnSe substrate and in metal microchannels have been probed by Fourier transform infrared imaging microspectroscopy. Absolute extinction [(3.4±0.6)×10-7 cm2 at 3178 cm-1], scattering, and absorption cross sections for a single yeast cell and a vibrational absorption spectrum have been determined by comparing it to the scattering properties of single, isolated, latex microspheres (polystyrene, 5.0 μm in diameter) on ZnSe, which are well modeled by the Mie scattering theory. Single yeast cells were then placed into the holes of the IR plasmonic mesh, i.e., metal films with arrays of subwavelength holes, yielding "scatter-free" IR absorption spectra, which have undistorted vibrational lineshapes and a rising generic IR absorption baseline. Absolute extinction, scattering, and absorption spectral profiles were determined for a single, ellipsoidal yeast cell to characterize the interplay of these effects.

  6. Plasmonic Nanostructures for Biosensor Applications

    Science.gov (United States)

    Gadde, Akshitha

    Improving the sensitivity of existing biosensors is an active research topic that cuts across several disciplines, including engineering and biology. Optical biosensors are the one of the most diverse class of biosensors which can be broadly categorized into two types based on the detection scheme: label-based and label-free detection. In label-based detection, the target bio-molecules are labeled with dyes or tags that fluoresce upon excitation, indicating the presence of target molecules. Label-based detection is highly-sensitive, capable of single molecule detection depending on the detector type used. One method of improving the sensitivity of label-based fluorescence detection is by enhancement of the emission of the labels by coupling them with metal nanostructures. This approach is referred as plasmon-enhanced fluorescence (PEF). PEF is achieved by increasing the electric field around the nano metal structures through plasmonics. This increased electric field improves the enhancement from the fluorophores which in turn improves the photon emission from the fluorophores which, in turn, improves the limit of detection. Biosensors taking advantage of the plasmonic properties of metal films and nanostructures have emerged an alternative, low-cost, high sensitivity method for detecting labeled DNA. Localized surface plasmon resonance (LSPR) sensors employing noble metal nanostructures have recently attracted considerable attention as a new class of plasmonic nanosensors. In this work, the design, fabrication and characterization of plasmonic nanostructures is carried out. Finite difference time domain (FDTD) simulations were performed using software from Lumerical Inc. to design a novel LSPR structure that exhibit resonance overlapping with the absorption and emission wavelengths of quantum dots (QD). Simulations of a composite Au/SiO2 nanopillars on silicon substrate were performed using FDTD software to show peak plasmonic enhancement at QD emission wavelength

  7. Sensitive SERS detection at the single-particle level based on nanometer-separated mushroom-shaped plasmonic dimers

    Science.gov (United States)

    Xiang, Quan; Li, Zhiqin; Zheng, Mengjie; Liu, Qing; Chen, Yiqin; Yang, Lan; Jiang, Tian; Duan, Huigao

    2018-03-01

    Elevated metallic nanostructures with nanogaps (film deposition. By controlling the initial size of nanogaps in resist structures and the following deposited film thickness, metallic nanogaps could be tuned at the sub-10 nm scale with single-digit nanometer precision. Both experimental and simulated results revealed that gold dimer on mushroom-shaped pillars have the capability to achieve higher SERS enhancement factor comparing to those plasmonic dimers on cylindrical pillars or on a common SiO2/Si substrate, implying that the nanometer-gapped elevated dimer is an ideal platform to achieve the highest possible field enhancement for various plasmonic applications.

  8. Highly sensitive detection of molecular interactions with plasmonic optical fiber grating sensors.

    Science.gov (United States)

    Voisin, Valérie; Pilate, Julie; Damman, Pascal; Mégret, Patrice; Caucheteur, Christophe

    2014-01-15

    Surface Plasmon resonance (SPR) optical fiber biosensors constitute a miniaturized counterpart to the bulky prism configuration and offer remote operation in very small volumes of analyte. They are a cost-effective and relatively straightforward technique to yield in situ (or even possibly in vivo) molecular detection. The biosensor configuration reported in this work uses nanometric-scale gold-coated tilted fiber Bragg gratings (TFBGs) interrogated by light polarized radially to the optical fiber outer surface, so as to maximize the optical coupling with the SPR. These gratings were recently associated to aptamers to assess their label-free biorecognition capability in buffer and serum solutions. In this work, using the well-acknowledged biotin-streptavidin pair as a benchmark, we go forward in the demonstration of their unique sensitivity. In addition to the monitoring of the self-assembled monolayer (SAM) in real time, we report an unprecedented limit of detection (LOD) as low as 2 pM. Finally, an immunosensing experiment is realized with human transferrin (dissociation constant Kd~10(-8) M(-1)). It allows to assess both the reversibility and the robustness of the SPR-TFBG biosensors and to confirm their high sensitivity. © 2013 Published by Elsevier B.V.

  9. Single plasmonic nanoparticles for ultrasensitive DNA sensing: From invisible to visible.

    Science.gov (United States)

    Guo, Longhua; Chen, Lichan; Hong, Seungpyo; Kim, Dong-Hwan

    2016-05-15

    The background signal is a major factor that restricts the limit of detection of biosensors. Herein, we present a zero-background DNA-sensing approach that utilizes enzyme-guided gold nanoparticle (AuNP) enlargement. This sensing strategy is based on the finding that small nanoparticles are invisible under a darkfield optical microscope, thus completely eliminating the background signal. In the event of target binding, Ag deposition is triggered and enlarges the AuNP beyond its optical diffraction limit, thereby making the invisible AuNP visible. Because the plasmon scattering of Ag is stronger than that of Au, only a thin layer of Ag is required to greatly enhance the scattering intensity of the AuNPs. Our investigation revealed that a target DNA concentration as low as 5.0×10(-21)M can transform the darkfield image of the nanoparticle from completely dark (invisible) to a blue dot (visible). Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Integrated Optic Surface Plasmon Resonance Measurements in a Borosilicate Glass Substrate

    Directory of Open Access Journals (Sweden)

    Antonino Parisi

    2008-11-01

    Full Text Available The surface plasmon resonance (SPR technique is a well-known optical method that can be used to measure the refractive index of organic nano-layers adsorbed on a thin metal film. Although there are many configurations for measuring biomolecular interactions, SPR-based techniques play a central role in many current biosensing experiments, since they are the most suited for sensitive and quantitative kinetic measurements. Here we give some results from the analysis and numerical elaboration of SPR data from integrated optics experiments in a particular borosilicate glass, chosen for its composition offering the rather low refractive index of 1.4701 at 633 nm wavelength. These data regard the flow over the sensing region (metal window of different solutions with refractive indexes in the range of interest (1.3÷1.5 for the detection of contaminants in aqueous solutions. After a discussion of the principles of SPR, of the metal window design optimization by means of optical interaction numerical modeling, and of waveguide fabrication techniques, we give a description of system setup and experimental results. Optimum gold film window thickness and width in this guided-wave configuration has been for the first time derived and implemented on an integrated optic prototype device. Its characterization is given by means of the real time waveguide output intensity measurements, which correspond to the interaction between the sensing gold thin film window and the flowing analyte. The SPR curve was subsequently inferred. Finally, a modified version of the device is reported, with channel waveguides arranged in a Y-junction optical circuit, so that laser source stability requirements are lowered by a factor of 85 dB, making possible the use of low cost sources in practical applications.

  11. Optical tweezers and surface plasmon resonance combination system based on the high numerical aperture lens

    Science.gov (United States)

    Shan, Xuchen; Zhang, Bei; Lan, Guoqiang; Wang, Yiqiao; Liu, Shugang

    2015-11-01

    Biology and medicine sample measurement takes an important role in the microscopic optical technology. Optical tweezer has the advantage of accurate capture and non-pollution of the sample. The SPR(surface plasmon resonance) sensor has so many advantages include high sensitivity, fast measurement, less consumption of sample and label-free detection of biological sample that the SPR sensing technique has been used for surface topography, analysis of biochemical and immune, drug screening and environmental monitoring. If they combine, they will play an important role in the biological, chemical and other subjects. The system we propose use the multi-axis cage system, by using the methods of reflection and transmiss ion to improve the space utilization. The SPR system and optical tweezer were builtup and combined in one system. The cage of multi-axis system gives full play to its accuracy, simplicity and flexibility. The size of the system is 20 * 15 * 40 cm3 and thus the sample can be replaced to switch between the optical tweezers system and the SPR system in the small space. It means that we get the refractive index of the sample and control the particle in the same system. In order to control the revolving stage, get the picture and achieve the data stored automatically, we write a LabVIEW procedure. Then according to the data from the back focal plane calculate the refractive index of the sample. By changing the slide we can trap the particle as optical tweezer, which makes us measurement and trap the sample at the same time.

  12. Plasmonic Photonic-Crystal Slabs: Visualization of the Bloch Surface Wave Resonance for an Ultrasensitive, Robust and Reusable Optical Biosensor

    Directory of Open Access Journals (Sweden)

    Alexander V. Baryshev

    2014-12-01

    Full Text Available A one-dimensional photonic crystal (PhC with termination by a metal film—a plasmonic photonic-crystal slab—has been theoretically analyzed for its optical response at a variation of the dielectric permittivity of an analyte and at a condition simulating the molecular binding event. Visualization of the Bloch surface wave resonance (SWR was done with the aid of plasmon absorption in a dielectric/metal/dielectric sandwich terminating a PhC. An SWR peak in spectra of such a plasmonic photonic crystal (PPhC slab comprising a noble or base metal layer was shown to be sensitive to a negligible variation of refractive index of a medium adjoining to the slab. As a consequence, the considered PPhC-based optical sensors exhibited an enhanced sensitivity and a good robustness in comparison with the conventional surface-plasmon and Bloch surface wave sensors. The PPhC biosensors can be of practical importance because the metal layer is protected by a capping dielectric layer from contact with analytes and, consequently, from deterioration.

  13. Plasmonic nanoparticle scattering for color holograms.

    Science.gov (United States)

    Montelongo, Yunuen; Tenorio-Pearl, Jaime Oscar; Williams, Calum; Zhang, Shuang; Milne, William Ireland; Wilkinson, Timothy David

    2014-09-02

    This work presents an original approach to create holograms based on the optical scattering of plasmonic nanoparticles. By analogy to the diffraction produced by the scattering of atoms in X-ray crystallography, we show that plasmonic nanoparticles can produce a wave-front reconstruction when they are sampled on a diffractive plane. By applying this method, all of the scattering characteristics of the nanoparticles are transferred to the reconstructed field. Hence, we demonstrate that a narrow-band reconstruction can be achieved for direct white light illumination on an array of plasmonic nanoparticles. Furthermore, multicolor capabilities are shown with minimal cross-talk by multiplexing different plasmonic nanoparticles at subwavelength distances. The holograms were fabricated from a single subwavelength thin film of silver and demonstrate that the total amount of binary information stored in the plane can exceed the limits of diffraction and that this wavelength modulation can be detected optically in the far field.

  14. Platinum plasmonic nanostructure arrays for massively parallel single-molecule detection based on enhanced fluorescence measurements

    International Nuclear Information System (INIS)

    Saito, Toshiro; Takahashi, Satoshi; Obara, Takayuki; Itabashi, Naoshi; Imai, Kazumichi

    2011-01-01

    We fabricated platinum bowtie nanostructure arrays producing fluorescence enhancement and evaluated their performance using two-photon photoluminescence and single-molecule fluorescence measurements. A comprehensive selection of suitable materials was explored by electromagnetic simulation and Pt was chosen as the plasmonic material for visible light excitation near 500 nm, which is preferable for multicolor dye-labeling applications like DNA sequencing. The observation of bright photoluminescence (λ = 500-600 nm) from each Pt nanostructure, induced by irradiation at 800 nm with a femtosecond laser pulse, clearly indicates that a highly enhanced local field is created near the Pt nanostructure. The attachment of a single dye molecule was attempted between the Pt triangles of each nanostructure by using selective immobilization chemistry. The fluorescence intensities of the single dye molecule localized on the nanostructures were measured. A highly enhanced fluorescence, which was increased by a factor of 30, was observed. The two-photon photoluminescence intensity and fluorescence intensity showed qualitatively consistent gap size dependence. However, the average fluorescence enhancement factor was rather repressed even in the nanostructure with the smallest gap size compared to the large growth of photoluminescence. The variation of the position of the dye molecule attached to the nanostructure may influence the wide distribution of the fluorescence enhancement factor and cause the rather small average value of the fluorescence enhancement factor.

  15. Quantum and Classical Optics of Plasmonic Systems: 3D/2D Materials and Photonic Topological Insulators

    Science.gov (United States)

    Hassani Gangaraj, Seyyed Ali

    At the interface of two different media such as metal and vacuum, light can couple to the electrons of the metal to form a wave that is bound to the interface. This wave is called a surface plasmon-plariton (SPP), generally characterized by intense fields that decay quickly away from the interface. Due to their unique properties, SPPs have found a broad range of applications in various areas of science, including light harvesting, medical science, energy transfer and imaging. In addition to the widely studied classical plasmonics, quantum plasmonics is also attracting considerable interest in the electromagnetics and quantum optics communities. In this thesis several new areas of investigation into quantum plasmonics is presented, focusing on entanglement mediated by SPPs in several different environments: 3D waveguides, 2D surfaces and on photonic topological insulators. Entanglement is an experimentally verified property of nature where pairs of quantum systems are connected in some manner such that the quantum state of each system cannot be described independently. Generating, preserving, and controlling entanglement is necessary for many quantum computer implementations. It is highly desirable to control entanglement between two multi-level emitters such as quantum dots via a macroscopic, easily-adjusted external parameter. SPPs guided by the medium, as a coupling agent between quantum dots, are highly tunable and offer a promising way to achieve having control over a SPP mediated entanglement. We first consider two quantum dots placed above 3D finite length waveguides. We have restricted our consideration to two waveguides types, i.e. a metal nanowire and a groove waveguide. Our main results in this work are to show that realistic finite-length nanowire and groove waveguides, with their associated discontinuities, play a crucial role in the engineering of highly entangled states. It is demonstrated that proper positioning of the emitters with respect to the

  16. Tailored optical vector fields for ultrashort-pulse laser induced complex surface plasmon structuring.

    Science.gov (United States)

    Ouyang, J; Perrie, W; Allegre, O J; Heil, T; Jin, Y; Fearon, E; Eckford, D; Edwardson, S P; Dearden, G

    2015-05-18

    Precise tailoring of optical vector beams is demonstrated, shaping their focal electric fields and used to create complex laser micro-patterning on a metal surface. A Spatial Light Modulator (SLM) and a micro-structured S-waveplate were integrated with a picosecond laser system and employed to structure the vector fields into radial and azimuthal polarizations with and without a vortex phase wavefront as well as superposition states. Imprinting Laser Induced Periodic Surface Structures (LIPSS) elucidates the detailed vector fields around the focal region. In addition to clear azimuthal and radial plasmon surface structures, unique, variable logarithmic spiral micro-structures with a pitch Λ ∼1μm, not observed previously, were imprinted on the surface, confirming unambiguously the complex 2D focal electric fields. We show clearly also how the Orbital Angular Momentum(OAM) associated with a helical wavefront induces rotation of vector fields along the optic axis of a focusing lens and confirmed by the observed surface micro-structures.

  17. [Research on symmetrical optical waveguide based surface plasmon resonance sensing with spectral interrogation].

    Science.gov (United States)

    Zhang, Yi-long; Liu, Le; Guo, Jun; Zhang, Peng-fei; Guo, Ji-hua; Ma, Hui; He, Yong-hong

    2015-02-01

    Surface plasmon resonance (SPR) sensors with spectral interrogation can adopt fiber to transmit light signals, thus leaving the sensing part separated, which is very convenient for miniaturization, remote-sensing and on-site analysis. Symmetrical optical waveguide (SOW) SPR has the same refractive index of the-two buffer media layers adjacent to the metal film, resulting in longer propagation distance, deeper penetration depth and better performance compared to conventional SPR In the present paper, we developed a symmetrical optical, waveguide (SOW) SPR sensor with wavelength interrogation. In the system, MgF2-Au-MgF2 film was used as SOW module for glucose sensing, and a fiber based light source and detection was used in the spectral interrogation. In the experiment, a refractive index resolution of 2.8 x 10(-7) RIU in fluid protocol was acquired. This technique provides advantages of high resolution and could have potential use in compact design, on-site analysis and remote sensing.

  18. A Novel Fiber Optic Surface Plasmon Resonance Biosensors with Special Boronic Acid Derivative to Detect Glycoprotein

    Directory of Open Access Journals (Sweden)

    Yang Zhang

    2017-10-01

    Full Text Available We proposed and demonstrated a novel tilted fiber Bragg grating (TFBG-based surface plasmon resonance (SPR label-free biosensor via a special boronic acid derivative to detect glycoprotein with high sensitivity and selectivity. TFBG, as an effective sensing element for optical sensing in near-infrared wavelengths, possess the unique capability of easily exciting the SPR effect on fiber surface which coated with a nano-scale metal layer. SPR properties can be accurately detected by measuring the variation of transmitted spectra at optical communication wavelengths. In our experiment, a 10° TFBG coated with a 50 nm gold film was manufactured to stimulate SPR on a sensor surface. To detect glycoprotein selectively, the sensor was immobilized using designed phenylboronic acid as the recognition molecule, which can covalently bond with 1,2- or 1,3-diols to form five- or six-membered cyclic complexes for attaching diol-containing biomolecules and proteins. The phenylboronic acid was synthetized with long alkyl groups offering more flexible space, which was able to improve the capability of binding glycoprotein. The proposed TFBG-SPR sensors exhibit good selectivity and repeatability with a protein concentration sensitivity up to 2.867 dB/ (mg/mL and a limit of detection (LOD of 15.56 nM.

  19. A Molecularly Imprinted Polymer on a Plasmonic Plastic Optical Fiber to Detect Perfluorinated Compounds in Water

    Directory of Open Access Journals (Sweden)

    Nunzio Cennamo

    2018-06-01

    Full Text Available A novel Molecularly Imprinted Polymer (MIP able to bind perfluorinated compounds, combined with a surface plasmon resonance (SPR optical fiber platform, is presented. The new MIP receptor has been deposited on a D-shaped plastic optical fiber (POF covered with a photoresist buffer layer and a thin gold film. The experimental results have shown that the developed SPR-POF-MIP sensor makes it possible to selectively detect the above compounds. In this work, we present the results obtained with perfluorooctanoate (PFOA compound, and they hold true when obtained with a perfluorinated alkylated substances (PFAs mixture sample. The sensor’s response is the same for PFOA, perfluorooctanesulfonate (PFOS or PFA contaminants in the C4–C11 range. We have also tested a sensor based on a non-imprinted polymer (NIP on the same SPR in a D-shaped POF platform. The limit of detection (LOD of the developed chemical sensor was 0.13 ppb. It is similar to the one obtained by the configuration based on a specific antibody for PFOA/PFOS exploiting the same SPR-POF platform, already reported in literature. The advantage of an MIP receptor is that it presents a better stability out of the native environment, very good reproducibility, low cost and, furthermore, it can be directly deposited on the gold layer, without modifying the metal surface by functionalizing procedures.

  20. Quantum sized Ag nanocluster assisted fluorescence enhancement in Tm3+-Yb3+ doped optical fiber beyond plasmonics

    International Nuclear Information System (INIS)

    Chattopadhyay, Rik; Haldar, Arindam; Paul, Mukul C.; Das, Shyamal; Bhadra, Shyamal K.

    2015-01-01

    We report a process for enhancing fluorescence emission from conventional rare earth ions in optical fiber by metal nanocluster (MNC) in nonresonant indirect pumping. The process is completely different from formal metal enhanced fluorescence phenomenon as the MNCs are too small in size to support localized surface plasmon and the excitation wavelength is far from plasmon resonance frequency. We used an established theory of two coupled oscillators to explain the simultaneous enhancement of Ytterbium (Yb 3+ ) and Thulium (Tm 3+ ) emission by silver (Ag) NCs under nonresonant pumping in optical fiber. The fiber is pumped with a 980 nm fiber pigtailed laser diode with input power of 20–100 mW to excite the Yb 3+ . Four times enhancement of Yb 3+ emission of 900–1100 nm and Tm 3+ upconversion emission around 474 nm, 650 nm, and 790 nm is observed in the fiber with Ag NCs

  1. Plasmonic non-concentric nanorings array as an unidirectional nano-optical conveyor belt actuated by polarization rotation.

    Science.gov (United States)

    Jiang, Min; Wang, Guanghui; Jiao, Wenxiang; Ying, Zhoufeng; Zou, Ningmu; Ho, Ho-Pui; Sun, Tianyu; Zhang, Xuping

    2017-01-15

    We report a nano-optical conveyor belt containing an array of gold plasmonic non-concentric nanorings (PNNRs) for the realization of trapping and unidirectional transportation of nanoparticles through rotating the polarization of an excitation beam. The location of hot spots within an asymmetric plasmonic nanostructure is polarization dependent, thus making it possible to manipulate a trapped target by rotating the incident polarization state. In the case of PNNR, the two poles have highly unbalanced trap potential. This greatly enhances the chance of transferring trapped particles between adjacent PNNRs in a given direction through rotating the polarization. As confirmed by three-dimensional finite-difference time-domain analysis, an array of PNNRs forms an unidirectional nano-optical conveyor belt, which delivers target nanoparticles or biomolecules over a long distance with nanometer accuracy. With the capacity to trap and to transfer, our design offers a versatile scheme for conducting mechanical sample manipulation in many on-chip optofluidic applications.

  2. Applied optics. Gain modulation by graphene plasmons in aperiodic lattice lasers.

    Science.gov (United States)

    Chakraborty, S; Marshall, O P; Folland, T G; Kim, Y-J; Grigorenko, A N; Novoselov, K S

    2016-01-15

    Two-dimensional graphene plasmon-based technologies will enable the development of fast, compact, and inexpensive active photonic elements because, unlike plasmons in other materials, graphene plasmons can be tuned via the doping level. Such tuning is harnessed within terahertz quantum cascade lasers to reversibly alter their emission. This is achieved in two key steps: first, by exciting graphene plasmons within an aperiodic lattice laser and, second, by engineering photon lifetimes, linking graphene's Fermi energy with the round-trip gain. Modal gain and hence laser spectra are highly sensitive to the doping of an integrated, electrically controllable, graphene layer. Demonstration of the integrated graphene plasmon laser principle lays the foundation for a new generation of active, programmable plasmonic metamaterials with major implications across photonics, material sciences, and nanotechnology. Copyright © 2016, American Association for the Advancement of Science.

  3. All-optical bit magnitude comparator device using metal-insulator-metal plasmonic waveguide

    Science.gov (United States)

    Kumar, Santosh; Singh, Lokendra; Chen, Nan-Kuang

    2017-12-01

    A plasmonic metal-insulator-metal (MIM) waveguide has great success in confining the surface plasmon up to a deep subwavelength scale. The structure of a nonlinear Mach-Zehnder interferometer (MZI) using a plasmonic MIM waveguide has been analyzed. A one-bit magnitude comparator has been designed using an MZI and two linear control waveguides. The device works on the Kerr effect inside the plasmonics waveguide. The mathematical description of the device is explained. The simulation of the device is done using MATLAB® and the finite-difference time-domain (FDTD) method.

  4. Tailoring the optical constants in single-crystal silicon with embedded silver nanostructures for advanced silicon photonics applications

    International Nuclear Information System (INIS)

    Akhter, Perveen; Huang, Mengbing; Spratt, William; Kadakia, Nirag; Amir, Faisal

    2015-01-01

    Plasmonic effects associated with metal nanostructures are expected to hold the key to tailoring light emission/propagation and harvesting solar energy in materials including single crystal silicon which remains the backbone in the microelectronics and photovoltaics industries but unfortunately, lacks many functionalities needed for construction of advanced photonic and optoelectronics devices. Currently, silicon plasmonic structures are practically possible only in the configuration with metal nanoparticles or thin film arrays on a silicon surface. This does not enable one to exploit the full potential of plasmonics for optical engineering in silicon, because the plasmonic effects are dominant over a length of ∼50 nm, and the active device region typically lies below the surface much beyond this range. Here, we report on a novel method for the formation of silver nanoparticles embedded within a silicon crystal through metal gettering from a silver thin film deposited at the surface to nanocavities within the Si created by hydrogen ion implantation. The refractive index of the Ag-nanostructured layer is found to be 3–10% lower or higher than that of silicon for wavelengths below or beyond ∼815–900 nm, respectively. Around this wavelength range, the optical extinction values increase by a factor of 10–100 as opposed to the pure silicon case. Increasing the amount of gettered silver leads to an increased extinction as well as a redshift in wavelength position for the resonance. This resonance is attributed to the surface plasmon excitation of the resultant silver nanoparticles in silicon. Additionally, we show that the profiles for optical constants in silicon can be tailored by varying the position and number of nanocavity layers. Such silicon crystals with embedded metal nanostructures would offer novel functional base structures for applications in silicon photonics, optoelectronics, photovoltaics, and plasmonics

  5. Plasmonic detection and visualization of directed adsorption of charged single nanoparticles to patterned surfaces

    International Nuclear Information System (INIS)

    Scherbahn, Vitali; Nizamov, Shavkat; Mirsky, Vladimir M.

    2016-01-01

    It has recently been shown that surface plasmon microscopy (SPM) allows single nanoparticles (NPs) on sensor surfaces to be detected and analyzed. The authors have applied this technique to study the adsorption of single metallic and plastic NPs. Binding of gold NPs (40, 60 and 100 nm in size) and of 100 nm polystyrene NPs to gold surfaces modified by differently ω-functionalized alkyl thiols was studied first. Self-assembled monolayers (SAM) with varying terminal functions including amino, carboxy, oligo(ethylene glycol), methyl, or trimethylammonium groups were deposited on gold films to form surfaces possessing different charge and hydrophobicity. The affinity of NPs to these surfaces depends strongly on the type of coating. SAMs terminated with trimethylammonium groups and carboxy group display highly different affinity and therefore were preferred when creating patterned charged surfaces. Citrate-stabilized gold NPs and sulfate-terminated polystyrene NPs were used as negatively charged NPs, while branched polyethylenimine-coated silver NPs were used as positively charged NPs. It is shown that the charged patterned areas on the gold films are capable of selectively adsorbing oppositely charged NPs that can be detected and analyzed with an ∼1 ng⋅mL −1 detection limit. (author)

  6. Electromagnetic study of surface enhanced Raman scattering of plasmonic-biomolecule: An interaction between nanodimer and single biomolecule

    Science.gov (United States)

    Pandey, Gyanendra Krishna; Pathak, Nilesh Kumar; Uma, R.; Sharma, R. P.

    2017-04-01

    In this article we have investigated the electromagnetic surface enhanced Raman scattering (SERS) of single biomolecule adsorbed at the surface of spherical nanodimer. The SERS mechanism has been studied using first principle approach for spherical nanodimer geometry. The coupling of plasmonic concept to biomolecule results the broadband tunable enhancement in Raman gain factor. In this observation the enhancement factor was observed around ≈ 1015. The plasmonic properties of metal nanodimer are analysed in terms of surface plasmon resonances, extinction efficiency and polarisability that have been derived under quasistatic approximation. In this paper, various facets like interdipole separation, molecule distance and size of the plasmonic nanogeometry are taken into account to analyse the Raman gain factor. We also observe that the frequency range expands sufficiently which increases the broad detectability range of the molecule which generates signal even in the outside of Raman range i.e. in between IR to UV region. Lastly, the extinction spectra and electric field profile have been evaluated at resonance wavelength 364 nm. The comparison between electrostatic approach and numerical approach (using DDA) has also been done in terms of extinction spectra.

  7. Colloidal Plasmonic Titanium Nitride Nanoparticles: Properties and Applications

    Directory of Open Access Journals (Sweden)

    Guler Urcan

    2015-01-01

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

  8. Three-Dimensional Optical Trapping of a Plasmonic Nanoparticle using Low Numerical Aperture Optical Tweezers

    Czech Academy of Sciences Publication Activity Database

    Brzobohatý, Oto; Šiler, Martin; Trojek, Jan; Chvátal, Lukáš; Karásek, Vítězslav; Paták, Aleš; Pokorná, Zuzana; Mika, Filip; Zemánek, Pavel

    2015-01-01

    Roč. 5, JAN 29 (2015), 08106:1-9 ISSN 2045-2322 R&D Projects: GA ČR GB14-36681G Institutional support: RVO:68081731 Keywords : discrete-dipole approximation * gold nanoparticles * radiation forces * spectroscopy Subject RIV: BH - Optics, Masers, Lasers Impact factor: 5.228, year: 2015

  9. Ultra-fast all-optical plasmonic switching in near infra-red spectrum using a Kerr nonlinear ring resonator

    Science.gov (United States)

    Nurmohammadi, Tofiq; Abbasian, Karim; Yadipour, Reza

    2018-03-01

    In this paper, an all-optical plasmonic switch based on metal-insulator-metal (MIM) nanoplasmonic waveguide with a Kerr nonlinear ring resonator is introduced and studied. Two-dimensional simulations utilizing the finite-difference time-domain algorithm are used to demonstrate an apparent optical bistability and significant switching mechanisms (in enabled-low condition: T(ON/OFF) =21.9 and in enabled-high condition: T(ON/OFF) =24.9) of the signal light arisen by altering the pump-light intensity. The proposed all-optical switching demonstrates femtosecond-scale feedback time (90 fs) and then ultra-fast switching can be achieved. The offered all-optical switch may recognize potential significant applications in integrated optical circuits.

  10. Control of Resonances and Optical Properties of Plasmonic-Patch Metamaterials

    Science.gov (United States)

    2012-08-01

    nanostructures made of plasmonic materials like gold and silver can resonantly interact with radiation over a range of wavelengths from micro...specific metal nanostructures, such as nanorods, hemispheres, nanocrescent arrays, nanorings , dimers, nanoprisms, nanocrystals, nanoparticles in a periodic...known that nanostructures made of plasmonic materials like gold and silver can resonantly interact with radiation over a range of wavelengths from micro

  11. Optical characterization of broad plasmon resonances of Pd/Pt nanoparticles

    Science.gov (United States)

    Valizade-Shahmirzadi, N.; Pakizeh, T.

    2018-04-01

    In this paper, optical properties of nanoparticles (nanodisks and nanospheres) composed of photofunctional metals like palladium (Pd) and platinum (Pt) over a large dimension range are investigated using the electromagnetic simulation and quasi-static theory. These characteristics are compared with their counterparts in plasmonic gold (Au) nanoparticles. Pd/Pt-nanodisks with larger dimension have higher absorption and lower scattering efficiencies than Au-nanodisks that accompany with lower extinction efficiencies and broader resonances. Although an increment in the dimension (diameter and height) of Au/Pd/Pt-nanoparticles decreases the absorption-to-scattering ratios, these ratios are less sensitive to the height size in Au-nanodisks, which causes their LSPR spectra become much broader. It is noteworthy that the LSPR quality factor of Pd nanoparticles is improved by considering the radiative damping and depolarization in quasi-static method unlike the Au nanoparticles. The importance of the highly absorptive Pd/Pt nanoparticles can be traced in the photo-functionalized and energy applications.

  12. Transferability of antibody pairs from ELISA to fiber optic surface plasmon resonance for infliximab detection

    Science.gov (United States)

    Van Stappen, Thomas; Lu, Jiadi; Bloemen, Maarten; Geukens, Nick; Spasic, Dragana; Delport, Filip; Verbiest, Thierry; Lammertyn, Jeroen; Gils, Ann

    2015-03-01

    Tumor necrosis factor (TNF)-alpha is a pleiotropic cytokine up-regulated in inflammatory bowel disease, rheumatoid arthritis and psoriasis. The introduction of anti-TNF drugs such as infliximab has revolutionized the treatment of these diseases. Recently, therapeutic drug monitoring (TDM) of infliximab has been introduced in clinical decision making to increase cost-efficiency. Nowadays, TDM is performed using radio-immunoassays, homogeneous mobility shift assays or ELISA. Unfortunately, these assays do not allow for in situ treatment optimization, because of the required sample transportation to centralized laboratories and the subsequent assay execution time. In this perspective, we evaluated the potential of fiber optic-surface plasmon resonance (FO-SPR). To achieve this goal, a panel of 55 monoclonal anti-infliximab antibodies (MA-IFX) was developed and characterized in-house, leading to the identification of nine different clusters. Based on this high diversity, 22 antibody pairs were selected and tested for their reactivity towards IFX, using one MA-IFX as capture and one MA-IFX for detection, in a sandwich type ELISA and FO-SPR. This study showed that the reactivity towards IFX of each antibody pair in ELISA is highly similar to its reactivity on FO-SPR, indicating that antibody pairs are easily transferable between both platforms. Given the fact that FO-SPR shows the potential for miniaturization and fast assay time, it can be considered a highly promising platform for on-site infliximab monitoring.

  13. Label-Enhanced Surface Plasmon Resonance: A New Concept for Improved Performance in Optical Biosensor Analysis

    Directory of Open Access Journals (Sweden)

    Niko Granqvist

    2013-11-01

    Full Text Available Surface plasmon resonance (SPR is a well-established optical biosensor technology with many proven applications in the study of molecular interactions as well as in surface and material science. SPR is usually applied in the label-free mode which may be advantageous in cases where the presence of a label may potentially interfere with the studied interactions per se. However, the fundamental challenges of label-free SPR in terms of limited sensitivity and specificity are well known. Here we present a new concept called label-enhanced SPR, which is based on utilizing strongly absorbing dye molecules in combination with the evaluation of the full shape of the SPR curve, whereby the sensitivity as well as the specificity of SPR is significantly improved. The performance of the new label-enhanced SPR method was demonstrated by two simple model assays: a small molecule assay and a DNA hybridization assay. The small molecule assay was used to demonstrate the sensitivity enhancement of the method, and how competitive assays can be used for relative affinity determination. The DNA assay was used to demonstrate the selectivity of the assay, and the capabilities in eliminating noise from bulk liquid composition variations.

  14. Label-Enhanced Surface Plasmon Resonance: A New Concept for Improved Performance in Optical Biosensor Analysis

    Science.gov (United States)

    Granqvist, Niko; Hanning, Anders; Eng, Lars; Tuppurainen, Jussi; Viitala, Tapani

    2013-01-01

    Surface plasmon resonance (SPR) is a well-established optical biosensor technology with many proven applications in the study of molecular interactions as well as in surface and material science. SPR is usually applied in the label-free mode which may be advantageous in cases where the presence of a label may potentially interfere with the studied interactions per se. However, the fundamental challenges of label-free SPR in terms of limited sensitivity and specificity are well known. Here we present a new concept called label-enhanced SPR, which is based on utilizing strongly absorbing dye molecules in combination with the evaluation of the full shape of the SPR curve, whereby the sensitivity as well as the specificity of SPR is significantly improved. The performance of the new label-enhanced SPR method was demonstrated by two simple model assays: a small molecule assay and a DNA hybridization assay. The small molecule assay was used to demonstrate the sensitivity enhancement of the method, and how competitive assays can be used for relative affinity determination. The DNA assay was used to demonstrate the selectivity of the assay, and the capabilities in eliminating noise from bulk liquid composition variations. PMID:24217357

  15. Enhancing Optically Pumped Organic-Inorganic Hybrid Perovskite Amplified Spontaneous Emission via Compound Surface Plasmon Resonance

    Directory of Open Access Journals (Sweden)

    Xiaoyan Wu

    2018-03-01

    Full Text Available Organic-inorganic hybrid perovskite has attracted intensive attention from researchers as the gain medium in lasing devices. However, achieving electrically driven lasing remains a significant challenge. Modifying the devices’ structure to enhance the optically pumped amplified spontaneous emission (ASE is the key issue. In this work, gold nanoparticles (Au NPs are first doped into PEDOT: PSS buffer layer in a slab waveguide device structure: Quartz/PEDOT: PSS (with or w/o Au NPs/CH3NH3PbBr3. As a result, the facile device shows a significantly enhanced ASE intensity and a narrowed full width at half maximum. Based on experiments and theoretical simulation data, the improvement is mainly a result of the compound surface plasmon resonance, including simultaneous near- and far-field effects, both of which could increase the density of excitons excited state and accelerate the radiative decay process. This method is highly significant for the design and development and fabrication of high-performance organic-inorganic hybrid perovskite lasing diodes.

  16. Localized surface plasmon resonance (LSPR) study of DNA hybridization at single nanoparticle transducers

    International Nuclear Information System (INIS)

    Schneider, T.; Jahr, N.; Jatschka, J.; Csaki, A.; Stranik, O.; Fritzsche, W.

    2013-01-01

    The effect of DNA–DNA interaction on the localized surface plasmon resonance of single 80 nm gold nanoparticles is studied. Therefore, both the attachment of the capture DNA strands at the particle surface and the sequence-specific DNA binding (hybridization) of analyte DNA to the immobilized capture DNA is subject of investigations. The influence of substrate attachment chemistry, the packing density of DNA as controlled by an assisting layer of smaller molecules, and the distance as increased by a linker on the LSPR efficiency is investigated. The resulting changes in signal can be related to a higher hybridization efficiency of the analyte DNA to the immobilized capture DNA. The subsequent attachment of additional DNA strands to this system is studied, which allows for a multiple step detection of binding and an elucidation of the resulting resonance shifts. The detection limit was determined for the utilized DNA system by incubation with various concentration of analyte DNA. Although the method allows for a marker-free detection, we show that additional markers such as 20 nm gold particle labels increase the signal and thereby the sensitivity significantly. The study of resonance shift for various DNA lengths revealed that the resonance shift per base is stronger for shorter DNA molecules (20 bases) as compared to longer ones (46 bases).

  17. Constructed Single-Crystal Rutile TiO_2 Cluster and Plasmon Synergistic Effect for Dye-Sensitized Solar Cells

    International Nuclear Information System (INIS)

    Yu, Wenjing; Sun, Weiwei; Liu, Yumin; Mehnane, Hadja Fatima; Liu, Haimin; Zhang, Kun; Cai, Bo; Liu, Wei; Guo, Shishang; Zhao, Xing-Zhong

    2015-01-01

    We demonstrate a method for incorporating plasmon metallic nanoparticles in hierarchical rutile TiO_2 clusters (RTC) assembled from single-crystal nanospindles. The RTC could efficiently improve the diffusion of the photoelectrons, which can be ascribed to the improvement of the connectivity by bridging the neighbouring microflowers through the single-crystal nanospindles. But not all the nanospindles are tightly interconnected, hence organic colloid has been prepared for post-treatment of the device based on RTC by the generation of TiO_2 nanoparticles. When added into Au nanoparticles, localized electric fields can be produced, because Au can excite dye molecules more intensively than incident far-field light. The surface plasmon synergistic effect had been investigated by Uv-vis absorption spectrum of Au@ organic colloid and the relative change of the IPCE. As a result, the cell based on RTC exhibits an overall conversion efficiency of 7.68%, indicating a 17% promotion compared with that derived from commercial P25 (6.58%) which could be ascribed to faster electron transfer of single-crystal nanospindles. With the Au nanoparticles incorporation in RTC, the device achieves a conversion efficiency of 9.15%, resulting in a 11% increase compared to the RTC device post-treated by organic colloid without Au nanoparticles (8.24%), which is attributed to the surface plasmon synergistic of Au nanoparticles.

  18. Searching for better plasmonic materials

    DEFF Research Database (Denmark)

    West, P.; Ishii, S.; Naik, G.

    2010-01-01

    Plasmonics is a research area merging the fields of optics and nanoelectronics by confining light with relatively large free-space wavelength to the nanometer scale - thereby enabling a family of novel devices. Current plasmonic devices at telecommunication and optical frequencies face significan...... for realizing optimal plasmonic material properties for specific frequencies and applications, thereby providing a reference for those searching for better plasmonic materials....

  19. Metal Nitrides for Plasmonic Applications

    DEFF Research Database (Denmark)

    Naik, Gururaj V.; Schroeder, Jeremy; Guler, Urcan

    2012-01-01

    Metal nitrides as alternatives to metals such as gold could offer many advantages when used as plasmonic material. We show that transition metal nitrides can replace metals providing equally good optical performance for many plasmonic applications.......Metal nitrides as alternatives to metals such as gold could offer many advantages when used as plasmonic material. We show that transition metal nitrides can replace metals providing equally good optical performance for many plasmonic applications....

  20. Enhancement of Ag-Based Plasmonic Photocatalysis in Hydrogen Production from Ammonia Borane by the Assistance of Single-Site Ti-Oxide Moieties within a Silica Framework.

    Science.gov (United States)

    Verma, Priyanka; Kuwahara, Yasutaka; Mori, Kohsuke; Yamashita, Hiromi

    2017-03-13

    Ag nanoparticles (NPs) have gained great attention owing to their interesting plasmonic properties and efficient catalysis under visible-light irradiation. In this study, an Ag-based plasmonic catalyst supported on mesoporous silica with isolated and tetrahedrally coordinated single-site Ti-oxide moieties, namely, Ag/Ti-SBA-15, was designed with the purpose of utilizing the broad spectral range of solar energy. The Ti-SBA-15 support allows the deposition of small Ag NPs with a narrow size distribution. The chemical structure, morphology, and optical properties of the prepared catalyst were characterized by techniques such as UV/Vis, FT extended X-ray absorption fine structure, and X-ray photoelectron spectroscopy, field-emission SEM, TEM, and N 2 physisorption studies. The catalytic activity of Ag/Ti-SBA-15 in hydrogen production from ammonia borane by hydrolysis was significantly enhanced in comparison with Ag/SBA-15 without Ti-oxide moieties and Ag/TiO 2 /SBA-15 involving agglomerated TiO 2 , both in the dark and under light irradiation. Improved electron transfer under light irradiation caused by the creation of heterojunctions between Ag NPs and Ti-oxide moieties explains the results obtained in the present study. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Surface plasmon resonances, optical properties, and electrical conductivity thermal hystersis of silver nanofibers produced by the electrospinning technique.

    Science.gov (United States)

    Barakat, Nasser A M; Woo, Kee-Do; Kanjwal, Muzafar A; Choi, Kyung Eun; Khil, Myung Seob; Kim, Hak Yong

    2008-10-21

    In the present study, silver metal nanofibers have been successfully prepared by using the electrospinning technique. Silver nanofibers have been produced by electrospinning a sol-gel consisting of poly(vinyl alcohol) and silver nitrate. The dried nanofiber mats have been calcined at 850 degrees C in an argon atmosphere. The produced nanofibers do have distinct plasmon resonance compared with the reported silver nanoparticles. Contrary to the introduced shapes of silver nanoparticles, the nanofibers have a blue-shifted plasmon resonance at 330 nm. Moreover, the optical properties study indicated that the synthesized nanofibers have two band gap energies of 0.75 and 2.34 eV. An investigation of the electrical conductivity behavior of the obtained nanofibers shows thermal hystersis. These privileged physical features greatly widen the applications of the prepared nanofibers in various fields.

  2. Ultrasensitive Detection of Single-Walled Carbon Nanotubes Using Surface Plasmon Resonance.

    Science.gov (United States)

    Jang, Daeho; Na, Wonhwi; Kang, Minwook; Kim, Namjoon; Shin, Sehyun

    2016-01-05

    Because single-walled carbon nanotubes (SWNTs) are known to be a potentially dangerous material, inducing cancers and other diseases, any possible leakage of SWNTs through an aquatic medium such as drinking water will result in a major public threat. To solve this problem, for the present study, a highly sensitive, quantitative detection method of SWNTs in an aqueous solution was developed using surface plasmon resonance (SPR) spectroscopy. For a highly sensitive and specific detection, a strong affinity conjugation with biotin-streptavidin was adopted on an SPR sensing mechanism. During the pretreatment process, the SWNT surface was functionalized and hydrophilized using a thymine-chain based biotinylated single-strand DNA linker (B-ssDNA) and bovine serum albumin (BSA). The pretreated SWNTs were captured on a sensing film, the surface of which was immobilized with streptavidin on biotinylated gold film. The captured SWNTs were measured in real-time using SPR spectroscopy. Specific binding with SWNTs was verified through several validation experiments. The present method using an SPR sensor is capable of detecting SWNTs of as low as 100 fg/mL, which is the lowest level reported thus far for carbon-nanotube detection. In addition, the SPR sensor showed a linear characteristic within the range of 100 pg/mL to 200 ng/mL. These findings imply that the present SPR sensing method can detect an extremely low level of SWNTs in an aquatic environment with high sensitivity and high specificity, and thus any potential leakage of SWNTs into an aquatic environment can be precisely monitored within a couple of hours.

  3. Recent Progress on Plasmon-Enhanced Fluorescence

    Directory of Open Access Journals (Sweden)

    Dong Jun

    2015-12-01

    Full Text Available The optically generated collective electron density waves on metal–dielectric boundaries known as surface plasmons have been of great scientific interest since their discovery. Being electromagnetic waves on gold or silver nanoparticle’s surface, localised surface plasmons (LSP can strongly enhance the electromagnetic field. These strong electromagnetic fields near the metal surfaces have been used in various applications like surface enhanced spectroscopy (SES, plasmonic lithography, plasmonic trapping of particles, and plasmonic catalysis. Resonant coupling of LSPs to fluorophore can strongly enhance the emission intensity, the angular distribution, and the polarisation of the emitted radiation and even the speed of radiative decay, which is so-called plasmon enhanced fluorescence (PEF. As a result, more and more reports on surface-enhanced fluorescence have appeared, such as SPASER-s, plasmon assisted lasing, single molecule fluorescence measurements, surface plasmoncoupled emission (SPCE in biological sensing, optical orbit designs etc. In this review, we focus on recent advanced reports on plasmon-enhanced fluorescence (PEF. First, the mechanism of PEF and early results of enhanced fluorescence observed by metal nanostructure will be introduced. Then, the enhanced substrates, including periodical and nonperiodical nanostructure, will be discussed and the most important factor of the spacer between molecule and surface and wavelength dependence on PEF is demonstrated. Finally, the recent progress of tipenhanced fluorescence and PEF from the rare-earth doped up-conversion (UC and down-conversion (DC nanoparticles (NPs are also commented upon. This review provides an introduction to fundamentals of PEF, illustrates the current progress in the design of metallic nanostructures for efficient fluorescence signal amplification that utilises propagating and localised surface plasmons.

  4. Quantitative optical extinction-based parametric method for sizing a single core-shell Ag-Ag2O nanoparticle

    International Nuclear Information System (INIS)

    Santillan, J M J; Scaffardi, L B; Schinca, D C

    2011-01-01

    This paper develops a parametric method for determining the core radius and shell thickness in small silver-silver-oxide core-shell nanoparticles (Nps) based on single particle optical extinction spectroscopy. The method is based on the study of the relationship between plasmon peak wavelength, full width at half maximum (FWHM) and contrast of the extinction spectra as a function of core radius and shell thickness. This study reveals that plasmon peak wavelength is strongly dependent on shell thickness, whereas FWHM and contrast depend on both variables. These characteristics may be used for establishing an easy and fast stepwise procedure to size core-shell NPs from single particle absorption spectrum. The importance of the method lies in the possibility of monitoring the growth of the silver-oxide layer around small spherical silver Nps in real time. Using the electrostatic approximation of Mie theory, core-shell single particle extinction spectra were calculated for a silver particle's core size smaller than about 20 nm and different thicknesses of silver oxide around it. Analysis of the obtained curves shows a very particular characteristic of the plasmon peak of small silver-silver-oxide Nps, expressed in the fact that its position is strongly dependent on oxide thickness and weakly dependent on the core radius. Even a very thin oxide layer shifts the plasmon peak noticeably, enabling plasmon tuning with appropriate shell thickness. This characteristic, together with the behaviour of FWHM and contrast of the extinction spectra can be combined into a parametric method for sizing both core and shell of single silver Nps in a medium using only optical information. In turn, shell thickness can be related to oxygen content in the Np's surrounding media. The method proposed is applied to size silver Nps from single particle extinction spectrum. The results are compared with full optical spectrum fitting using the electrostatic approximation in Mie theory. The method

  5. Single Photon Source with a Diamond Nanocrystal on an Optical Nanofiber

    International Nuclear Information System (INIS)

    Lars Liebermeister

    2014-01-01

    The development of high yield single photon sources is crucial for applications in quantum information science as well as for experiments on the foundations of quantum physics. The NV-center in diamond is a promising solid state candidate. By using nanodiamonds the single photon emission can easily be coupled to integrated nano-optical and plasmonic structures. Our approach is to utilize efficient coupling of fluorescence of a single NV-center to the evanescent field of an optical nanofiber. A hybrid microscope (confocal microscope combined with an AFM) allows to optically characterize and preselect diamond nanocrystals and then to apply an AFM nanomanipulation technique to move a selected nanodiamond deterministically onto the tapered optical fiber. We report on first results with single diamond nanocrystals containing several NV-centers positioned on a tapered optical fiber. We observe fluorescence emission in the guided mode of the fiber. The second order correlation recorded between the free-space and the guided fluorescence shows pronounced antibunching. This demonstrated efficient evanescent coupling with low background. (author)

  6. Single gold nanoparticle plasmonic spectroscopy for study of chemical-dependent efflux function of single ABC transporters of single live Bacillus subtilis cells.

    Science.gov (United States)

    Browning, Lauren M; Lee, Kerry J; Cherukuri, Pavan K; Huang, Tao; Songkiatisak, Preeyaporn; Warren, Seth; Xu, Xiao-Hong Nancy

    2018-03-26

    ATP-binding cassette (ABC) membrane transporters serve as self-defense transport apparatus in many living organisms and they can selectively extrude a wide variety of substrates, leading to multidrug resistance (MDR). The detailed molecular mechanisms remain elusive. Single nanoparticle plasmonic spectroscopy highly depends upon their sizes, shapes, chemical and surface properties. In our previous studies, we have used the size-dependent plasmonic spectra of single silver nanoparticles (Ag NPs) to study the real-time efflux kinetics of the ABC (BmrA) transporter and MexAB-OprM transporter in single live cells (Gram-positive and Gram-negative bacterium), respectively. In this study, we prepared and used purified, biocompatible and stable (non-aggregated) gold nanoparticles (Au NPs) (12.4 ± 0.9 nm) to study the efflux kinetics of single BmrA membrane transporters of single live Bacillus subtillis cells, aiming to probe chemical dependent efflux functions of BmrA transporters and their potential chemical sensing capability. Similar to those observed using Ag NPs, accumulation of the intracellular Au NPs in single live cells (WT and ΔBmrA) highly depends upon the cellular expression of BmrA and the NP concentration (0.7 and 1.4 nM). The lower accumulation of intracellular Au NPs in WT (normal expression of BmrA) than ΔBmrA (deletion of bmrA) indicates that BmrA extrudes the Au NPs out of the WT cells. The accumulation of Au NPs in the cells increases with NP concentration, suggesting that the Au NPs most likely passively diffuse into the cells, similar to antibiotics. The result demonstrates that such small Au NPs can serve as imaging probes to study the efflux function of the BmrA membrane transporter in single live cells. Furthermore, the dependence of the accumulation rate of intracellular Au NPs in single live cells upon the expression of BmrA and the concentration of the NPs is about twice higher than that of the same sized Ag NPs. This interesting finding

  7. Modes and Mode Volumes for Leaky Optical Cavities and Plasmonic Nanoresonators

    DEFF Research Database (Denmark)

    Hughes, Stephen; Kristensen, Philip Trøst

    2013-01-01

    Electromagnetic cavity modes in photonic and plasmonic resonators offer rich and attractive regimes for tailoring the properties of light–matter interactions, yet there is a disturbing lack of a precise definition for what constitutes a cavity mode, and as a result their mathematical properties r...... methods for quasinormal modes of both photonic and plasmonic resonators and the concept of a generalized effective mode volume, and we illustrate the theory with several representative cavity structures from the fields of photonic crystals and nanoplasmonics....

  8. 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 eleme......-element simulations. Our approach can be used for development of next generation of tunable plasmonic and hybrid nanophotonic devices.......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...... elements enhances the interaction of incident radiation with the graphene sheet and enables efficient electrical modulation of the plasmonic resonance. We observe electrically controlled damping in the Fano resonances occurring at approximately 2 μm, and the results are verified by full-wave 3D finite...

  9. On-chip plasmon-induced transparency based on plasmonic coupled nanocavities.

    Science.gov (United States)

    Zhu, Yu; Hu, Xiaoyong; Yang, Hong; Gong, Qihuang

    2014-01-17

    On-chip plasmon-induced transparency offers the possibility of realization of ultrahigh-speed information processing chips. Unfortunately, little experimental progress has been made to date because it is difficult to obtain on-chip plasmon-induced transparency using only a single meta-molecule in plasmonic circuits. Here, we report a simple and efficient strategy to realize on-chip plasmon-induced transparency in a nanoscale U-shaped plasmonic waveguide side-coupled nanocavity pair. High tunability in the transparency window is achieved by covering the pair with different organic polymer layers. It is possible to realize ultrafast all-optical tunability based on pump light-induced refractive index change of a graphene cover layer. Compared with previous reports, the overall feature size of the plasmonic nanostructure is reduced by more than three orders of magnitude, while ultrahigh tunability of the transparency window is maintained. This work also provides a superior platform for the study of the various physical effects and phenomena of nonlinear optics and quantum optics.

  10. Effect of multiple plasmon excitation on single, double and multiple ionizations of C{sub 60} in collisions with fast highly charged Si ions

    Energy Technology Data Exchange (ETDEWEB)

    Kelkar, A H; Kadhane, U; Misra, D; Kumar, A; Tribedi, L C [Tata Institute of Fundamental Research, Colaba, Mumbai -5 (India)

    2007-06-28

    We have investigated the single and multiple ionizations of the C{sub 60} molecule in collisions with fast Si{sup q+} projectiles for various projectile charge states (q) between q = 6 and 14. The q-dependence of the ionization cross sections and their ratios is compared with the giant dipole plasmon resonance (GDPR) model. The excellent qualitative agreement with the model in case of single and double ionizations and also a reasonable agreement with the triple (and to some extent with quadruple) ionization (without evaporation) yields signify dominant contributions of the single-, double- and triple-plasmon excitations on the single- and multiple-ionization process.

  11. Terahertz instability of surface optical-phonon polaritons that interact with surface plasmon polaritons in the presence of electron drift

    International Nuclear Information System (INIS)

    Sydoruk, O.; Solymar, L.; Shamonina, E.; Kalinin, V.

    2010-01-01

    Traveling-wave interaction between optical phonons and electrons drifting in diatomic semiconductors has potential for amplification and generation of terahertz radiation. Existing models of this interaction were developed for infinite materials. As a more practically relevant configuration, we studied theoretically a finite semiconductor slab surrounded by a dielectric. This paper analyzes the optical-phonon instability in the slab including the Lorentz force and compares it to the instability in an infinite material. As the analysis shows, the slab instability occurs because of the interaction of surface optical-phonon polaritons with surface plasmon polaritons in the presence of electron drift. The properties of the instability depend on the slab thickness when the thickness is comparable to the wavelength. For large slab thicknesses, however, the dispersion relation of the slab is similar to that of an infinite material, although the coupling is weaker. The results could be used for the design of practical terahertz traveling-wave oscillators and amplifiers.

  12. Tunable optical switching in the near-infrared spectral regime by employing plasmonic nanoantennas containing phase change materials.

    Science.gov (United States)

    Savaliya, Priten B; Thomas, Arun; Dua, Rishi; Dhawan, Anuj

    2017-10-02

    We propose the design of switchable plasmonic nanoantennas (SPNs) that can be employed for optical switching in the near-infrared regime. The proposed SPNs consist of nanoantenna structures made up of a plasmonic metal (gold) such that these nanoantennas are filled with a switchable material (vanadium dioxide). We compare the results of these SPNs with inverted SPN structures that consist of gold nanoantenna structures surrounded by a layer of vanadium dioxide (VO 2 ) on their outer surface. These nanoantennas demonstrate switching of electric-field intensity enhancement (EFIE) between two states (On and Off states), which can be induced thermally, optically or electrically. The On and Off states of the nanoantennas correspond to the metallic and semiconductor states, respectively of the VO 2 film inside or around the nanoantennas, as the VO 2 film exhibits phase transition from its semiconductor state to the metallic state upon application of thermal, optical, or electrical energy. We employ finite-difference time-domain (FDTD) simulations to demonstrate switching in the EFIE for four different SPN geometries - nanorod-dipole, bowtie, planar trapezoidal toothed log-periodic, and rod-disk - and compare their near-field distributions for the On and Off states of the SPNs. We also demonstrate that the resonance wavelength of the EFIE spectra gets substantially modified when these SPNs switch between the two states.

  13. Magneto-optical properties of BiFeO3 thin films using surface plasmon resonance technique

    International Nuclear Information System (INIS)

    Paliwal, Ayushi; Sharma, Anjali; Tomar, Monika; Gupta, Vinay

    2014-01-01

    Indigeneously assembled surface plasmon resonance (SPR) set up has been exploited to study the magnetic field dependent optical properties of BiFeO 3 thin films. BiFeO 3 thin films have been deposited onto gold (Au) coated glass prism by using pulsed laser deposition technique. The surface plasmon modes in prism/Au/BiFeO 3 /air structure have been excited in Kretschmann configuration at the interface of Au/BiFeO 3 thin films. The SPR reflectance curves obtained for prism/Au/BiFeO 3 /air structure were utilized to investigate the optical properties of BiFeO 3 thin films at optical frequency (λ=633 nm) as a function of applied magnetic field. SPR curves shows a continuous shift towards lower angles with increasing applied magnetic field, which indicate the promising application of ferromagnetic BiFeO 3 film as a magnetic field sensor. Complex dielectric constant of deposited BiFeO 3 film was determined by fitting the experimental SPR data with Fresnel's equations. The variation of complex dielectric constant and refractive index of BiFeO 3 film was studied with increase in magnetic field, and the sensitivity of magnetic field sensor was found to be about 0.52 RIU/T

  14. Magneto-optical properties of BiFeO{sub 3} thin films using surface plasmon resonance technique

    Energy Technology Data Exchange (ETDEWEB)

    Paliwal, Ayushi; Sharma, Anjali [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Tomar, Monika [Physics Department, Miranda House, University of Delhi, Delhi 110007 (India); Gupta, Vinay, E-mail: drguptavinay@gmail.com [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India)

    2014-09-01

    Indigeneously assembled surface plasmon resonance (SPR) set up has been exploited to study the magnetic field dependent optical properties of BiFeO{sub 3} thin films. BiFeO{sub 3} thin films have been deposited onto gold (Au) coated glass prism by using pulsed laser deposition technique. The surface plasmon modes in prism/Au/BiFeO{sub 3}/air structure have been excited in Kretschmann configuration at the interface of Au/BiFeO{sub 3} thin films. The SPR reflectance curves obtained for prism/Au/BiFeO{sub 3}/air structure were utilized to investigate the optical properties of BiFeO{sub 3} thin films at optical frequency (λ=633 nm) as a function of applied magnetic field. SPR curves shows a continuous shift towards lower angles with increasing applied magnetic field, which indicate the promising application of ferromagnetic BiFeO{sub 3} film as a magnetic field sensor. Complex dielectric constant of deposited BiFeO{sub 3} film was determined by fitting the experimental SPR data with Fresnel's equations. The variation of complex dielectric constant and refractive index of BiFeO{sub 3} film was studied with increase in magnetic field, and the sensitivity of magnetic field sensor was found to be about 0.52 RIU/T.

  15. Single Nanoparticle Detection Using Optical Microcavities.

    Science.gov (United States)

    Zhi, Yanyan; Yu, Xiao-Chong; Gong, Qihuang; Yang, Lan; Xiao, Yun-Feng

    2017-03-01

    Detection of nanoscale objects is highly desirable in various fields such as early-stage disease diagnosis, environmental monitoring and homeland security. Optical microcavity sensors are renowned for ultrahigh sensitivities due to strongly enhanced light-matter interaction. This review focuses on single nanoparticle detection using optical whispering gallery microcavities and photonic crystal microcavities, both of which have been developing rapidly over the past few years. The reactive and dissipative sensing methods, characterized by light-analyte interactions, are explained explicitly. The sensitivity and the detection limit are essentially determined by the cavity properties, and are limited by the various noise sources in the measurements. On the one hand, recent advances include significant sensitivity enhancement using techniques to construct novel microcavity structures with reduced mode volumes, to localize the mode field, or to introduce optical gain. On the other hand, researchers attempt to lower the detection limit by improving the spectral resolution, which can be implemented by suppressing the experimental noises. We also review the methods of achieving a better temporal resolution by employing mode locking techniques or cavity ring up spectroscopy. In conclusion, outlooks on the possible ways to implement microcavity-based sensing devices and potential applications are provided. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Single-spin stochastic optical reconstruction microscopy.

    Science.gov (United States)

    Pfender, Matthias; Aslam, Nabeel; Waldherr, Gerald; Neumann, Philipp; Wrachtrup, Jörg

    2014-10-14

    We experimentally demonstrate precision addressing of single-quantum emitters by combined optical microscopy and spin resonance techniques. To this end, we use nitrogen vacancy (NV) color centers in diamond confined within a few ten nanometers as individually resolvable quantum systems. By developing a stochastic optical reconstruction microscopy (STORM) technique for NV centers, we are able to simultaneously perform sub-diffraction-limit imaging and optically detected spin resonance (ODMR) measurements on NV spins. This allows the assignment of spin resonance spectra to individual NV center locations with nanometer-scale resolution and thus further improves spatial discrimination. For example, we resolved formerly indistinguishable emitters by their spectra. Furthermore, ODMR spectra contain metrology information allowing for sub-diffraction-limit sensing of, for instance, magnetic or electric fields with inherently parallel data acquisition. As an example, we have detected nuclear spins with nanometer-scale precision. Finally, we give prospects of how this technique can evolve into a fully parallel quantum sensor for nanometer resolution imaging of delocalized quantum correlations.

  17. Robust plasmonic substrates

    DEFF Research Database (Denmark)

    Kostiučenko, Oksana; Fiutowski, Jacek; Tamulevicius, Tomas

    2014-01-01

    Robustness is a key issue for the applications of plasmonic substrates such as tip-enhanced Raman spectroscopy, surface-enhanced spectroscopies, enhanced optical biosensing, optical and optoelectronic plasmonic nanosensors and others. A novel approach for the fabrication of robust plasmonic...... substrates is presented, which relies on the coverage of gold nanostructures with diamond-like carbon (DLC) thin films of thicknesses 25, 55 and 105 nm. DLC thin films were grown by direct hydrocarbon ion beam deposition. In order to find the optimum balance between optical and mechanical properties...

  18. Giant plasmon excitation in single and double ionization of C60 by fast highly charged Si and O ions

    International Nuclear Information System (INIS)

    Kelkar, A H; Kadhane, U; Misra, D; Tribedi, L C

    2007-01-01

    Se have investigated single and double ionization of C 60 molecule in collisions with 2.33 MeV/u Si q+ (q=6-14) and 3.125 MeV/u O q+ (q=5-8) projectiles. The projectile charge state dependence of the single and double ionization yields of C 60 are then compared to those for an ion-atom collision system using Ne gas as a target. A large difference between the gas and the cluster target behaviour was partially explained in terms of a model based on collective excitation namely the giant dipole plasmon resonance (GDPR). The qualitative agreement between the data and GDPR model prediction for single and double ionization signifies the importance of single and double plasmon excitations in the ionization process. A large deviation of the GDPR model for triple and quadruple ionization from the experimental data imply the importance of the other low impact parameter processes such as evaporation, fragmentation and a possible solid-like dynamical screening

  19. Multi-scale theory-assisted nano-engineering of plasmonic-organic hybrid electro-optic device performance

    Science.gov (United States)

    Elder, Delwin L.; Johnson, Lewis E.; Tillack, Andreas F.; Robinson, Bruce H.; Haffner, Christian; Heni, Wolfgang; Hoessbacher, Claudia; Fedoryshyn, Yuriy; Salamin, Yannick; Baeuerle, Benedikt; Josten, Arne; Ayata, Masafumi; Koch, Ueli; Leuthold, Juerg; Dalton, Larry R.

    2018-02-01

    Multi-scale (correlated quantum and statistical mechanics) modeling methods have been advanced and employed to guide the improvement of organic electro-optic (OEO) materials, including by analyzing electric field poling induced electro-optic activity in nanoscopic plasmonic-organic hybrid (POH) waveguide devices. The analysis of in-device electro-optic activity emphasizes the importance of considering both the details of intermolecular interactions within organic electro-optic materials and interactions at interfaces between OEO materials and device architectures. Dramatic improvement in electro-optic device performance-including voltage-length performance, bandwidth, energy efficiency, and lower optical losses have been realized. These improvements are critical to applications in telecommunications, computing, sensor technology, and metrology. Multi-scale modeling methods illustrate the complexity of improving the electro-optic activity of organic materials, including the necessity of considering the trade-off between improving poling-induced acentric order through chromophore modification and the reduction of chromophore number density associated with such modification. Computational simulations also emphasize the importance of developing chromophore modifications that serve multiple purposes including matrix hardening for enhanced thermal and photochemical stability, control of matrix dimensionality, influence on material viscoelasticity, improvement of chromophore molecular hyperpolarizability, control of material dielectric permittivity and index of refraction properties, and control of material conductance. Consideration of new device architectures is critical to the implementation of chipscale integration of electronics and photonics and achieving the high bandwidths for applications such as next generation (e.g., 5G) telecommunications.

  20. Mass production compatible fabrication techniques of single-crystalline silver metamaterials and plasmonics devices

    Science.gov (United States)

    Rodionov, Ilya A.; Baburin, Alexander S.; Zverev, Alexander V.; Philippov, Ivan A.; Gabidulin, Aidar R.; Dobronosova, Alina A.; Ryzhova, Elena V.; Vinogradov, Alexey P.; Ivanov, Anton I.; Maklakov, Sergey S.; Baryshev, Alexander V.; Trofimov, Igor V.; Merzlikin, Alexander M.; Orlikovsky, Nikolay A.; Rizhikov, Ilya A.

    2017-08-01

    During last 20 years, great results in metamaterials and plasmonic nanostructures fabrication were obtained. However, large ohmic losses in metals and mass production compatibility still represent the most serious challenge that obstruct progress in the fields of metamaterials and plasmonics. Many recent research are primarily focused on developing low-loss alternative materials, such as nitrides, II-VI semiconductor oxides, high-doped semiconductors, or two-dimensional materials. In this work, we demonstrate that our perfectly fabricated silver films can be an effective low-loss material system, as theoretically well-known. We present a fabrication technology of plasmonic and metamaterial nanodevices on transparent (quartz, mica) and non-transparent (silicon) substrates by means of e-beam lithography and ICP dry etch instead of a commonly-used focused ion beam (FIB) technology. We eliminate negative influence of litho-etch steps on silver films quality and fabricate square millimeter area devices with different topologies and perfect sub-100 nm dimensions reproducibility. Our silver non-damage fabrication scheme is tested on trial manufacture of spasers, plasmonic sensors and waveguides, metasurfaces, etc. These results can be used as a flexible device manufacture platform for a broad range of practical applications in optoelectronics, communications, photovoltaics and biotechnology.

  1. Chip-integrated plasmonic cavity-enhanced single nitrogen-vacancy center emission

    DEFF Research Database (Denmark)

    Siampour, Hamidreza; Kumar, Shailesh; Bozhevolnyi, Sergey I.

    2017-01-01

    High temporal stability and spin dynamics of individual nitrogen-vacancy (NV) centers in diamond crystals make them one of the most promising quantum emitters operating at room temperature. We demonstrate a chip-integrated cavity-coupled emission into propagating surface plasmon polariton (SPP...

  2. Surface plasmon modes of a single silver nanorod: An electron energy loss study

    DEFF Research Database (Denmark)

    Nicoletti, Olivia; Wubs, Martijn; Mortensen, N. Asger

    2011-01-01

    We present an electron energy loss study using energy filtered TEM of spatially resolved surface plasmon excitations on a silver nanorod of aspect ratio 14.2 resting on a 30 nm thick silicon nitride membrane. Our results show that the excitation is quantized as resonant modes whose intensity maxima...

  3. Excitation of surface plasmon polariton modes with multiple nitrogen vacancy centers in single nanodiamonds

    DEFF Research Database (Denmark)

    Kumar, Shailesh; Lausen, Jens L.; Garcia-Ortiz, Cesar E.

    2016-01-01

    ) are especially useful as biological fluorophores due to their chemical neutrality, brightness and room-temperature photostability. Furthermore, NDs containing multiple NV centers also have potential in high-precision magnetic field and temperature sensing. Coupling NV centers to propagating surface plasmon...

  4. Nanoscale Plasmonic V-Groove Waveguides for the Interrogation of Single Fluorescent Bacterial Cells

    DEFF Research Database (Denmark)

    Lotan, Oren; Bar-David, Jonathan; Smith, Cameron

    2017-01-01

    We experimentally demonstrate the interrogation of an individual Escherichia coli cell using a nanoscale plasmonic V-groove waveguide. Several different configurations were studied. The first involved the excitation of the cell in a liquid environment because it flows on top of the waveguide...

  5. Design and synthesis of plasmonic magnetic nanoparticles

    International Nuclear Information System (INIS)

    Lim, Jit Kang; Tilton, Robert D.; Eggeman, Alexander; Majetich, Sara A.

    2007-01-01

    Core-shell nanoparticles containing both iron oxide and gold are proposed for bioseparation applications. The surface plasmon resonance of gold makes it possible to track the positions of individual particles, even when they are smaller than the optical diffraction limit. The synthesis of water-dispersible iron oxide-gold nanoparticles is described. Absorption spectra show the plasmon peaks for Au shells on silica particles, suggesting that thin shells may be sufficient to impart a strong surface plasmon resonance to iron oxide-gold nanoparticles. Dark field optical microscopy illustrates the feasibility of single-particle detection. Calculations of magnetophoretic and drag forces for particles of different sizes reveal design requirements for effective separation of these small particles

  6. Partial Polarization in Interfered Plasmon Fields

    Directory of Open Access Journals (Sweden)

    P. Martínez Vara

    2014-01-01

    Full Text Available We describe the polarization features for plasmon fields generated by the interference between two elemental surface plasmon modes, obtaining a set of Stokes parameters which allows establishing a parallelism with the traditional polarization model. With the analysis presented, we find the corresponding coherence matrix for plasmon fields incorporating to the plasmon optics the study of partial polarization effects.

  7. Tailored Surfaces/Assemblies for Molecular Plasmonics and Plasmonic Molecular Electronics.

    Science.gov (United States)

    Lacroix, Jean-Christophe; Martin, Pascal; Lacaze, Pierre-Camille

    2017-06-12

    Molecular plasmonics uses and explores molecule-plasmon interactions on metal nanostructures for spectroscopic, nanophotonic, and nanoelectronic devices. This review focuses on tailored surfaces/assemblies for molecular plasmonics and describes active molecular plasmonic devices in which functional molecules and polymers change their structural, electrical, and/or optical properties in response to external stimuli and that can dynamically tune the plasmonic properties. We also explore an emerging research field combining molecular plasmonics and molecular electronics.

  8. Efficient interfacing of light and surface plasmon polaritons for quantum optics applications

    DEFF Research Database (Denmark)

    Eran, Kot

    interaction are the window to the underlying quantum world. It is no surprise then that there has always been push to find more, and gain better control over systems in which this interaction can be studied. In the past two decades, this end was further motivated as applications were envisioned to coherent...... control of matter. These include applications such as efficient photon collection, single-photon switching and transistors, and long-range optical coupling of quantum bits for quantum communications. However, generating and controlling strong coherent interaction between otherwise very weakly interacting...... light and quantum emitters proves a difficult task. Current days solutions range from cavities, atomic ensembles, photonic band gaps structures, ion traps and optical latices are all being improved and studied but none has yet to emerge as superior. Recently, another proposal for such a strong coupling...

  9. Quantum mechanical limit to plasmonic enhancement as observed by surface-enhanced Raman scattering.

    Science.gov (United States)

    Zhu, Wenqi; Crozier, Kenneth B

    2014-10-14

    Plasmonic nanostructures enable light to be concentrated into nanoscale 'hotspots', wherein the intensity of light can be enhanced by orders of magnitude. This plasmonic enhancement significantly boosts the efficiency of nanoscale light-matter interactions, enabling unique linear and nonlinear optical applications. Large enhancements are often observed within narrow gaps or at sharp tips, as predicted by the classical electromagnetic theory. Only recently has it become appreciated that quantum mechanical effects could emerge as the feature size approaches atomic length-scale. Here we experimentally demonstrate, through observations of surface-enhanced Raman scattering, that the emergence of electron tunnelling at optical frequencies limits the maximum achievable plasmonic enhancement. Such quantum mechanical effects are revealed for metallic nanostructures with gap-widths in the single-digit angstrom range by correlating each structure with its optical properties. This work furthers our understanding of quantum mechanical effects in plasmonic systems and could enable future applications of quantum plasmonics.

  10. Optical fiber sensor based on surface plasmon resonance for rapid detection of avian influenza virus subtype H6: Initial studies.

    Science.gov (United States)

    Zhao, Xihong; Tsao, Yu-Chia; Lee, Fu-Jung; Tsai, Woo-Hu; Wang, Ching-Ho; Chuang, Tsung-Liang; Wu, Mu-Shiang; Lin, Chii-Wann

    2016-07-01

    A side-polished fiber optic surface plasmon resonance (SPR) sensor was fabricated to expose the core surface and then deposited with a 40 nm thin gold film for the near surface sensing of effective refractive index changes with surface concentration or thickness of captured avian influenza virus subtype H6. The detection surface of the SPR optical fiber sensor was prepared through the plasma modification method for binding a self-assembled monolayer of isopropanol chemically on the gold surface of the optical fiber. Subsequently, N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide/N-hydroxysuccinimide was activated to enable EB2-B3 monoclonal antibodies to capture A/chicken/Taiwan/2838V/00 (H6N1) through a flow injection system. The detection limit of the fabricated optical fiber sensor for A/chicken/Taiwan/2838V/00 was 5.14 × 10(5) EID50/0.1 mL, and the response time was 10 min on average. Moreover, the fiber optic sensor has the advantages of a compact size and low cost, thus rendering it suitable for online and remote sensing. The results indicated that the optical fiber sensor can be used for epidemiological surveillance and diagnosing of avian influenza subtype H6 rapidly. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Analysis of near-field components of a plasmonic optical antenna and their contribution to quantum dot infrared photodetector enhancement.

    Science.gov (United States)

    Gu, Guiru; Vaillancourt, Jarrod; Lu, Xuejun

    2014-10-20

    In this paper, we analyze near-field vector components of a metallic circular disk array (MCDA) plasmonic optical antenna and their contribution to quantum dot infrared photodetector (QDIP) enhancement. The near-field vector components of the MCDA optical antenna and their distribution in the QD active region are simulated. The near-field overlap integral with the QD active region is calculated at different wavelengths and compared with the QDIP enhancement spectrum. The x-component (E(x)) of the near-field vector shows a larger intensity overlap integral and stronger correlation with the QDIP enhancement than E(z) and thus is determined to be the major near-field component to the QDIP enhancement.

  12. Low energy routing platforms for optical interconnects using active plasmonics integrated with Silicon Photonics

    DEFF Research Database (Denmark)

    Vyrsokinos, K.; Papaioannou, S.; Kalavrouziotis, D.

    2013-01-01

    technologies to cope with the massive amount of data moving across all hierarchical communication levels, namely rack-to-rack, backplane, chip-to-chip and even on-chip interconnections. Plasmonics comes indeed as a disruptive technology that enables seamless interoperability between light beams and electronic...

  13. Changing optical band structure with single photons

    Science.gov (United States)

    Albrecht, Andreas; Caneva, Tommaso; Chang, Darrick E.

    2017-11-01

    Achieving strong interactions between individual photons enables a wide variety of exciting possibilities in quantum information science and many-body physics. Cold atoms interfaced with nanophotonic structures have emerged as a platform to realize novel forms of nonlinear interactions. In particular, when atoms are coupled to a photonic crystal waveguide, long-range atomic interactions can arise that are mediated by localized atom-photon bound states. We theoretically show that in such a system, the absorption of a single photon can change the band structure for a subsequent photon. This occurs because the first photon affects the atoms in the chain in an alternating fashion, thus leading to an effective period doubling of the system and a new optical band structure for the composite atom-nanophotonic system. We demonstrate how this mechanism can be engineered to realize a single-photon switch, where the first incoming photon switches the system from being highly transmissive to highly reflective, and analyze how signatures can be observed via non-classical correlations of the outgoing photon field.

  14. Plasmonic Organic Photovoltaics: Unraveling Plasmonic Enhancement for Realistic Cell Geometries

    DEFF Research Database (Denmark)

    Beliatis, Michail

    2018-01-01

    Incorporating plasmonic nanoparticles in organic photovoltaic (OPV) devices can increase the optical thickness of the organic absorber layer while keeping its physical thickness small. However, trade-offs between various structure parameters have caused contradictions regarding the effectiveness...... of plasmonics in the literature, that have somewhat stunted the progressing of a unified theoretical understanding for practical applications. We examine the optical enhancement mechanisms of practical PCDTBT:PC70BM OPV cells incorporating metal nanoparticles. The plasmonic near- and far-field contributions...... show that an already optimized PCDTBT:PC70BM cell can be further optically enhanced by plasmonic effects by at least 20% with the incorporation of Ag nanoparticles....

  15. Optimize Etching Based Single Mode Fiber Optic Temperature Sensor

    OpenAIRE

    Ajay Kumar; Dr. Pramod Kumar

    2014-01-01

    This paper presents a description of etching process for fabrication single mode optical fiber sensors. The process of fabrication demonstrates an optimized etching based method to fabricate single mode fiber (SMF) optic sensors in specified constant time and temperature. We propose a single mode optical fiber based temperature sensor, where the temperature sensing region is obtained by etching its cladding diameter over small length to a critical value. It is observed that th...

  16. Quantum optics with single quantum dot devices

    International Nuclear Information System (INIS)

    Zwiller, Valery; Aichele, Thomas; Benson, Oliver

    2004-01-01

    A single radiative transition in a single-quantum emitter results in the emission of a single photon. Single quantum dots are single-quantum emitters with all the requirements to generate single photons at visible and near-infrared wavelengths. It is also possible to generate more than single photons with single quantum dots. In this paper we show that single quantum dots can be used to generate non-classical states of light, from single photons to photon triplets. Advanced solid state structures can be fabricated with single quantum dots as their active region. We also show results obtained on devices based on single quantum dots

  17. Nano-structure and optical properties (plasmonic) of graded helical square tower-like (terraced) Mn sculptured thin films

    Energy Technology Data Exchange (ETDEWEB)

    Savaloni, Hadi, E-mail: savaloni@khayam.ut.ac.ir [Department of Physics, University of Tehran, North-Kargar Street, Tehran (Iran, Islamic Republic of); Fakharpour, Mahsa [Department of Physics, Islamic Azad University, Science and Research Branch, Tehran (Iran, Islamic Republic of); Siabi-Garjan, Araz [Department of Advanced Technologies, University of Mohaghegh Ardabili, Namin, Ardabil (Iran, Islamic Republic of); Department of Materials Engineering and Nanotechnology, Sabalan University of Advanced Technologies (SUAT), Namin (Iran, Islamic Republic of); Placido, Frank [SUPA and Institute of Thin Films, Sensors and Imaging, University of The West of Scotland, High Street, Paisley (United Kingdom); Babaei, Ferydon [Department of Physics, University of Qom, Qom (Iran, Islamic Republic of)

    2017-01-30

    Highlights: • Graded helical square tower-like terraced sculptured Mn thin films are produced with different number of arms. • XRD, AFM, FESEM and optical analyses as well as theoretical calculations are carried out. • Intensity of Plasmon peaks depend on the polarization, the incident angle, and the distance from the shadowing block. • The presence of defects in these sculptured structures can be predicted by theoretical investigation. • Experimental and theoretical investigations show consistent results. - Abstract: Graded helical square tower-like terraced sculptured Mn thin films (GHSTTS) are produced in three stages with different number of arms using oblique angle deposition together with rotation of substrate holder about its surface normal, plus a shadowing block fixed at the centre of the substrate holder. The structural characterization of the produced samples was obtained using field emission scanning electron microscope (FESEM) and atomic force microscope (AFM). Results showed a structural gradient with distance from the edge of the shadowing block, which in turn is responsible for the decrease in the volume of void fraction and increase of grain size. Plasmon absorption peaks observed in the optical analysis of these nano-structures showed that their wavelength region and intensity depend on the polarization and the incident angle of light, as well as the distance from the edge of the shadowing block. According to our model and discrete dipole approximation (DDA) calculations, when the number of parallel nano-rods of different lengths and radii are increased the peak in the spectrum shifts to shorter wavelengths (blue shift). Also when the diameters of the nano-rods increases (a situation that occurs with increasing film thickness) the results is again a blue shift in the spectrum. The presence of defects in these sculptured structures caused by the shadowing effect is predicted by the theoretical DDA investigation of their optical spectra

  18. Surface plasmon enhancement in gold nanoparticles in the presence of an optical gain medium: an analysis

    Energy Technology Data Exchange (ETDEWEB)

    Sathiyamoorthy, K; Sreekanth, K V; Sidharthan, R; Murukeshan, V M [School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Xing Bengang, E-mail: mmurukeshan@ntu.edu.sg [Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371 (Singapore)

    2011-10-26

    The localized surface plasmon (LSP) enhancement in a gold nanoparticle is demonstrated in this paper. The enhancement of LSP is influenced by both size and the dielectric gain medium surrounding the nanoparticles. The nanoparticle is found to induce plasmonic enhancement of varying degrees depending on its size, and it is inferred that a gold nanoparticle of size 60 nm exhibits the maximum LSP for 532 nm excitation. Singularity due to cancellation of SP loss by an infinite gain medium and LSP enhancement are studied using a pump-probe Rayleigh scattering experiment. Gold nanoparticles of average size 60 nm exhibit the lowest threshold power to observe Rayleigh scattering. Furthermore, compared with the bare nanoparticles, a 12.5 fold enhancement of LSP is observed when the nanoparticle of average size 60 nm is kept in the gain medium.

  19. Plasmonics of magnetic and topological graphene-based nanostructures

    Science.gov (United States)

    Kuzmin, Dmitry A.; Bychkov, Igor V.; Shavrov, Vladimir G.; Temnov, Vasily V.

    2018-02-01

    Graphene is a unique material in the study of the fundamental limits of plasmonics. Apart from the ultimate single-layer thickness, its carrier concentration can be tuned by chemical doping or applying an electric field. In this manner, the electrodynamic properties of graphene can be varied from highly conductive to dielectric. Graphene supports strongly confined, propagating surface plasmon polaritons (SPPs) in a broad spectral range from terahertz to mid-infrared frequencies. It also possesses a strong magneto-optical response and thus provides complimentary architectures to conventional magneto-plasmonics based on magneto-optically active metals or dielectrics. Despite a large number of review articles devoted to plasmonic properties and applications of graphene, little is known about graphene magneto-plasmonics and topological effects in graphene-based nanostructures, which represent the main subject of this review. We discuss several strategies to enhance plasmonic effects in topologically distinct closed surface landscapes, i.e. graphene nanotubes, cylindrical nanocavities and toroidal nanostructures. A novel phenomenon of the strongly asymmetric SPP propagation on chiral meta-structures and the fundamental relations between structural and plasmonic topological indices are reviewed.

  20. 2D surface optical lattice formed by plasmon polaritons with application to nanometer-scale molecular deposition.

    Science.gov (United States)

    Yin, Yanning; Xu, Supeng; Li, Tao; Yin, Yaling; Xia, Yong; Yin, Jianping

    2017-08-10

    Surface plasmon polaritons, due to their tight spatial confinement and high local intensity, hold great promises in nanofabrication which is beyond the diffraction limit of conventional lithography. Here, we demonstrate theoretically the 2D surface optical lattices based on the surface plasmon polariton interference field, and the potential application to nanometer-scale molecular deposition. We present the different topologies of lattices generated by simple configurations on the substrate. By explicit theoretical derivations, we explain their formation and characteristics including field distribution, periodicity and phase dependence. We conclude that the topologies can not only possess a high stability, but also be dynamically manipulated via changing the polarization of the excitation laser. Nanometer-scale molecular deposition is simulated with these 2D lattices and discussed for improving the deposition resolution. The periodic lattice point with a width resolution of 33.2 nm can be obtained when the fullerene molecular beam is well-collimated. Our study can offer a superior alternative method to fabricate the spatially complicated 2D nanostructures, with the deposition array pitch serving as a reference standard for accurate and traceable metrology of the SI length standard.

  1. Nonlinear graphene plasmonics

    Science.gov (United States)

    Ooi, Kelvin J. A.; Tan, Dawn T. H.

    2017-10-01

    The rapid development of graphene has opened up exciting new fields in graphene plasmonics and nonlinear optics. Graphene's unique two-dimensional band structure provides extraordinary linear and nonlinear optical properties, which have led to extreme optical confinement in graphene plasmonics and ultrahigh nonlinear optical coefficients, respectively. The synergy between graphene's linear and nonlinear optical properties gave rise to nonlinear graphene plasmonics, which greatly augments graphene-based nonlinear device performance beyond a billion-fold. This nascent field of research will eventually find far-reaching revolutionary technological applications that require device miniaturization, low power consumption and a broad range of operating wavelengths approaching the far-infrared, such as optical computing, medical instrumentation and security applications.

  2. Molecular plasmonics

    CERN Document Server

    Fritzsche, Wolfgang

    2014-01-01

    Adopting a novel approach, this book provides a unique ""molecular perspective"" on plasmonics, concisely presenting the fundamentals and applications in a way suitable for beginners entering this hot field as well as for experienced researchers and practitioners. It begins by introducing readers to the optical effects that occur at the nanoscale and particularly their modification in the presence of biomolecules, followed by a concise yet thorough overview of the different methods for the actual fabrication of nanooptical materials. Further chapters address the relevant nanooptics, as well as

  3. Tunable optical properties of plasmonic Au/Al2O3 nanocomposite thin films analyzed by spectroscopic ellipsometry accounting surface characteristics.

    Science.gov (United States)

    Jaiswal, Jyoti; Mourya, Satyendra; Malik, Gaurav; Chandra, Ramesh

    2018-05-01

    In the present work, we have fabricated plasmonic gold/alumina nanocomposite (Au/Al 2 O 3 NC) thin films on a glass substrate at room temperature by RF magnetron co-sputtering. The influence of the film thickness (∼10-40  nm) on the optical and other physical properties of the samples was investigated and correlated with the structural and compositional properties. The X-ray diffractometer measurement revealed the formation of Au nanoparticles with average crystallite size (5-9.2 nm) embedded in an amorphous Al 2 O 3 matrix. The energy-dispersive X ray and X-ray photoelectron spectroscopy results confirmed the formation of Au/Al 2 O 3 NC quantitatively and qualitatively and it was observed that atomic% of Au increased by increasing thickness. The optical constants of the plasmonic Au/Al 2 O 3 NC thin films were examined by variable angle spectroscopic ellipsometry in the wide spectral range of 246-1688 nm, accounting the surface characteristics in the optical stack model, and the obtained results are expected to be unique. Additionally, a thickness-dependent blueshift (631-590 nm) of surface plasmon resonance peak was observed in the absorption spectra. These findings of the plasmonic Au/Al 2 O 3 NC films may allow the design and fabrication of small, compact, and efficient devices for optoelectronic and photonic applications.

  4. Refractometers for different refractive index range by surface plasmon resonance sensors in multimode optical fibers with different metals

    Science.gov (United States)

    Zuppella, P.; Corso, Alain J.; Pelizzo, Maria G.; Cennamo, N.; Zeni, L.

    2016-09-01

    We have realized a plasmonic sensor based on Au/Pd metal bilayer in a multimode plastic optical fiber. This metal bilayer, based on a metal with high imaginary part of the refractive index and gold, shows interesting properties in terms of sensitivity and performances, in different refractive index ranges. The development of highly sensitive platforms for high refractive index detection (higher than 1.38) is interesting for chemical applications based on molecularly imprinted polymer as receptors, while the aqueous medium is the refractive index range of biosensors based on bio-receptors. In this work we have presented an Au/Pd metal bilayer optimized for 1.38-1.42 refractive index range.

  5. Effect of Surface Plasmon Coupling to Optical Cavity Modes on the Field Enhancement and Spectral Response of Dimer-Based sensors

    KAUST Repository

    Alrasheed, Salma

    2017-09-05

    We present a theoretical approach to narrow the plasmon linewidth and enhance the near-field intensity at a plasmonic dimer gap (hot spot) through coupling the electric localized surface plasmon (LSP) resonance of a silver hemispherical dimer with the resonant modes of a Fabry-Perot (FP) cavity. The strong coupling is demonstrated by the large anticrossing in the reflection spectra and a Rabi splitting of 76 meV. Up to 2-fold enhancement increase can be achieved compared to that without using the cavity. Such high field enhancement has potential applications in optics, including sensors and high resolution imaging devices. In addition, the resonance splitting allows for greater flexibility in using the same array at different wavelengths. We then further propose a practical design to realize such a device and include dimers of different shapes and materials.

  6. Multispectral optical tweezers for molecular diagnostics of single biological cells

    Science.gov (United States)

    Butler, Corey; Fardad, Shima; Sincore, Alex; Vangheluwe, Marie; Baudelet, Matthieu; Richardson, Martin

    2012-03-01

    Optical trapping of single biological cells has become an established technique for controlling and studying fundamental behavior of single cells with their environment without having "many-body" interference. The development of such an instrument for optical diagnostics (including Raman and fluorescence for molecular diagnostics) via laser spectroscopy with either the "trapping" beam or secondary beams is still in progress. This paper shows the development of modular multi-spectral imaging optical tweezers combining Raman and Fluorescence diagnostics of biological cells.

  7. Optical levitation of microdroplet containing a single quantum dot

    OpenAIRE

    Minowa, Yosuke; Kawai, Ryoichi; Ashida, Masaaki

    2014-01-01

    We demonstrate the optical levitation or trapping in helium gas of a single quantum dot (QD) within a liquid droplet. Bright single photon emission from the levitated QD in the droplet was observed for more than 200 s. The observed photon count rates are consistent with the value theoretically estimated from the two-photon-action cross section. This paper presents the realization of an optically levitated solid-state quantum emitter. This paper was published in Optics Letters and is made avai...

  8. Customization of Protein Single Nanowires for Optical Biosensing.

    Science.gov (United States)

    Sun, Yun-Lu; Sun, Si-Ming; Wang, Pan; Dong, Wen-Fei; Zhang, Lei; Xu, Bin-Bin; Chen, Qi-Dai; Tong, Li-Min; Sun, Hong-Bo

    2015-06-24

    An all-protein single-nanowire optical biosensor is constructed by a facile and general femtosecond laser direct writing approach with nanoscale structural customization. As-formed protein single nanowires show excellent optical properties (fine waveguiding performance and bio-applicable transmission windows), and are utilized as evanescent optical nanobiosensors for label-free biotin detection. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Probing plasmonic nanostructures by photons and electrons

    DEFF Research Database (Denmark)

    Kneipp, Katrin; Kneipp, Harald; Kneipp, Janina

    2015-01-01

    We discuss recent developments for studying plasmonic metal nanostructures. Exploiting photons and electrons opens up new capabilities to probe the complete plasmon spectrum including bright and dark modes and related local optical fields at subnanometer spatial resolution. This comprehensive cha...

  10. Improvement of optical and electrical properties of indium tin oxide layer of GaN-based light-emitting diode by surface plasmon in silver nanoparticles

    International Nuclear Information System (INIS)

    Cho, Chu-Young; Hong, Sang-Hyun; Park, Seong-Ju

    2015-01-01

    We report on the effect of silver (Ag) nanoparticles on the optical transmittance and electrical conductivity of indium tin oxide (ITO) transparent conducting layer deposited on p-GaN layer of light-emitting diodes (LEDs). The sheet resistance of ITO and the series resistance of LEDs were decreased due to the increased electrical conductivity of ITO by Ag nanoparticles, compared with those of the LEDs with a bare ITO only. The ITO transmittance was also improved by localized surface plasmon resonance between the incident light and the randomly distributed Ag nanoparticles on ITO. The optical output power of LEDs with Ag nanoparticles on ITO was increased by 16% at 20 mA of injection current. - Highlights: • We studied the effect of Ag nanoparticles deposited on ITO on the properties of LED. • The optical power of LED and transmittance of ITO were improved by Ag surface plasmon. • The electrical conductivity of ITO was increased by Ag nanoparticles

  11. Plasmonic nanocomposite thin film enabled fiber optic sensors for simultaneous gas and temperature sensing at extreme temperatures.

    Science.gov (United States)

    Ohodnicki, Paul R; Buric, Michael P; Brown, Thomas D; Matranga, Christopher; Wang, Congjun; Baltrus, John; Andio, Mark

    2013-10-07

    Embedded sensors capable of operation in extreme environments including high temperatures, high pressures, and highly reducing, oxidizing and/or corrosive environments can make a significant impact on enhanced efficiencies and reduced greenhouse gas emissions of current and future fossil-based power generation systems. Relevant technologies can also be leveraged in a wide range of other applications with similar needs including nuclear power generation, industrial process monitoring and control, and aviation/aerospace. Here we describe a novel approach to embedded sensing under extreme temperature conditions by integration of Au-nanoparticle based plasmonic nanocomposite thin films with optical fibers in an evanescent wave absorption spectroscopy configuration. Such sensors can potentially enable simultaneous temperature and gas sensing at temperatures approaching 900-1000 °C in a manner compatible with embedded and distributed sensing approaches. The approach is demonstrated using the Au/SiO2 system deposited on silica-based optical fibers. Stability of optical fibers under relevant high temperature conditions and interactions with changing ambient gas atmospheres is an area requiring additional investigation and development but the simplicity of the sensor design makes it potentially cost-effective and may offer a potential for widespread deployment.

  12. Finite-element modeling of spontaneous emission of a quantum emitter at nanoscale proximity to plasmonic waveguides

    DEFF Research Database (Denmark)

    Chen, Yuntian; Nielsen, Torben Roland; Gregersen, Niels

    2010-01-01

    of the plasmonic waveguide can be arbitrary. The fraction of the energy coupled to the plasmonic mode can be calculated exactly, which can be used to determine the efficiency with which single optical plasmons are generated. We apply our numerical method to calculate the coupling of a quantum emitter......We develop a self-consistent finite-element method to quantitatively study spontaneous emission from emitters in nanoscale proximity of plasmonic waveguides. In the model, it is assumed that only one guided mode is dominatingly excited by the quantum emitter, while the cross section...

  13. Nonlinear optical studies of single gold nanoparticles

    NARCIS (Netherlands)

    Dijk, Meindert Alexander van

    2007-01-01

    Gold nanoparticles are spherical clusters of gold atoms, with diameters typically between 1 and 100 nanometers. The applications of these particles are rather diverse, from optical labels for biological experiments to data carrier for optical data storage. The goal of my project was to develop new

  14. Single domain antibody–quantum dot conjugates for ricin detection by both fluoroimmunoassay and surface plasmon resonance

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, George P. [Center for Bio/Molecular Science and Engineering, Code 6900, U. S. Naval Research Laboratory, 4555 Overlook Ave. S.W., Washington, DC 20375 (United States); Glaven, Richard H. [Nova Research, Inc., 1900 Elkin Street, Suite 230, Alexandria, VA 22308 (United States); Algar, W. Russ [Center for Bio/Molecular Science and Engineering, Code 6900, U. S. Naval Research Laboratory, 4555 Overlook Ave. S.W., Washington, DC 20375 (United States); College of Science, George Mason University, Fairfax, VA 22030 (United States); Susumu, Kimihiro [Optical Sciences Division, Code 5600, U. S. Naval Research Laboratory, 4555 Overlook Ave. S.W., Washington, DC 20375 (United States); Sotera Defense Solutions, Annapolis Junction, MD 20701 (United States); Stewart, Michael H. [Optical Sciences Division, Code 5600, U. S. Naval Research Laboratory, 4555 Overlook Ave. S.W., Washington, DC 20375 (United States); Medintz, Igor L. [Center for Bio/Molecular Science and Engineering, Code 6900, U. S. Naval Research Laboratory, 4555 Overlook Ave. S.W., Washington, DC 20375 (United States); Goldman, Ellen R., E-mail: ellen.goldman@nrl.navy.mil [Center for Bio/Molecular Science and Engineering, Code 6900, U. S. Naval Research Laboratory, 4555 Overlook Ave. S.W., Washington, DC 20375 (United States)

    2013-07-05

    Graphical abstract: -- Highlights: •Anti-ricin single domain antibodies (sdAb) were self-assembled on quantum dots (QDs). •Conjugates were prepared using dihydrolipoic acid-capped CdSe–ZnS core–shell QDs. •The sdAb–QD conjugates functioned in fluoroimmunoassays for ricin detection. •The conjugates provided signal amplification in surface plasmon resonance assays. •Conjugates provided sensitive detection compared to unconjugated sdAb reporters. -- Abstract: The combination of stable biorecognition elements and robust quantum dots (QDs) has the potential to yield highly effective reporters for bioanalyses. Llama-derived single domain antibodies (sdAb) provide small thermostable recognition elements that can be easily manipulated using standard DNA methods. The sdAb was self-assembled on dihydrolipoic acid (DHLA) ligand-capped CdSe–ZnS core–shell QDs made in our laboratory through the polyhistidine tail of the protein, which coordinated to zinc ions on the QD surface. The sdAb–QD bioconjugates were then applied in both fluorometric and surface plasmon resonance (SPR) immunoassays for the detection of ricin, a potential biothreat agent. The sdAb–QD conjugates functioned in fluoroimmunoassays for the detection of ricin, providing equivalent limits of detection when compared to the same anti-ricin sdAb labeled with a conventional fluorophore. In addition, the DHLA-QD–sdAb conjugates were very effective reporter elements in SPR sandwich assays, providing more sensitive detection with a signal enhancement of ∼10-fold over sdAb reporters and 2–4 fold over full sized antibody reporters. Commercially prepared streptavidin-modified polymer-coated QDs also amplified the SPR signal for the detection of ricin when applied to locations where biotinylated anti-ricin sdAb was bound to target; however, we observed a 4-fold greater amplification when using the DHLA-QD–sdAb conjugates in this format.

  15. Single domain antibody–quantum dot conjugates for ricin detection by both fluoroimmunoassay and surface plasmon resonance

    International Nuclear Information System (INIS)

    Anderson, George P.; Glaven, Richard H.; Algar, W. Russ; Susumu, Kimihiro; Stewart, Michael H.; Medintz, Igor L.; Goldman, Ellen R.

    2013-01-01

    Graphical abstract: -- Highlights: •Anti-ricin single domain antibodies (sdAb) were self-assembled on quantum dots (QDs). •Conjugates were prepared using dihydrolipoic acid-capped CdSe–ZnS core–shell QDs. •The sdAb–QD conjugates functioned in fluoroimmunoassays for ricin detection. •The conjugates provided signal amplification in surface plasmon resonance assays. •Conjugates provided sensitive detection compared to unconjugated sdAb reporters. -- Abstract: The combination of stable biorecognition elements and robust quantum dots (QDs) has the potential to yield highly effective reporters for bioanalyses. Llama-derived single domain antibodies (sdAb) provide small thermostable recognition elements that can be easily manipulated using standard DNA methods. The sdAb was self-assembled on dihydrolipoic acid (DHLA) ligand-capped CdSe–ZnS core–shell QDs made in our laboratory through the polyhistidine tail of the protein, which coordinated to zinc ions on the QD surface. The sdAb–QD bioconjugates were then applied in both fluorometric and surface plasmon resonance (SPR) immunoassays for the detection of ricin, a potential biothreat agent. The sdAb–QD conjugates functioned in fluoroimmunoassays for the detection of ricin, providing equivalent limits of detection when compared to the same anti-ricin sdAb labeled with a conventional fluorophore. In addition, the DHLA-QD–sdAb conjugates were very effective reporter elements in SPR sandwich assays, providing more sensitive detection with a signal enhancement of ∼10-fold over sdAb reporters and 2–4 fold over full sized antibody reporters. Commercially prepared streptavidin-modified polymer-coated QDs also amplified the SPR signal for the detection of ricin when applied to locations where biotinylated anti-ricin sdAb was bound to target; however, we observed a 4-fold greater amplification when using the DHLA-QD–sdAb conjugates in this format

  16. Revealing chemical processes and kinetics of drug action within single living cells via plasmonic Raman probes.

    Science.gov (United States)

    Li, Shan-Shan; Guan, Qi-Yuan; Meng, Gang; Chang, Xiao-Feng; Wei, Ji-Wu; Wang, Peng; Kang, Bin; Xu, Jing-Juan; Chen, Hong-Yuan

    2017-05-23

    Better understanding the drug action within cells may extend our knowledge on drug action mechanisms and promote new drugs discovery. Herein, we studied the processes of drug induced chemical changes on proteins and nucleic acids in human breast adenocarcinoma (MCF-7) cells via time-resolved plasmonic-enhanced Raman spectroscopy (PERS) in combination with principal component analysis (PCA). Using three popular chemotherapy drugs (fluorouracil, cisplatin and camptothecin) as models, chemical changes during drug action process were clearly discriminated. Reaction kinetics related to protein denaturation, conformational modification, DNA damage and their associated biomolecular events were calculated. Through rate constants and reaction delay times, the different action modes of these drugs could be distinguished. These results may provide vital insights into understanding the chemical reactions associated with drug-cell interactions.

  17. Nanoscale Plasmonic V-Groove Waveguides for the Interrogation of Single Fluorescent Bacterial Cells.

    Science.gov (United States)

    Lotan, Oren; Bar-David, Jonathan; Smith, Cameron L C; Yagur-Kroll, Sharon; Belkin, Shimshon; Kristensen, Anders; Levy, Uriel

    2017-09-13

    We experimentally demonstrate the interrogation of an individual Escherichia coli cell using a nanoscale plasmonic V-groove waveguide. Several different configurations were studied. The first involved the excitation of the cell in a liquid environment because it flows on top of the waveguide nanocoupler, while the obtained fluorescence is coupled into the waveguide and collected at the other nanocoupler. The other two configurations involved the positioning of the bacterium within the nanoscale waveguide and its excitation in a dry environment either directly from the top or through waveguide modes. This is achieved by taking advantage of the waveguide properties not only for light guiding but also as a mechanical tool for trapping the bacteria within the V-grooves. The obtained results are supported by a set of numerical simulations, shedding more light on the mechanism of excitation. This demonstration paves the way for the construction of an efficient bioplasmonic chip for diverse cell-based sensing applications.

  18. Plasmonic interferometers: From physics to biosensing applications

    Science.gov (United States)

    Zeng, Xie

    Optical interferometry has a long history and wide range of applications. In recent years, plasmonic interferometer arouses great interest due to its compact size and enhanced light-matter interaction. They have demonstrated attractive applications in biomolecule sensing, optical modulation/switching, and material characterization, etc. In this work, we first propose a practical far-field method to extract the intrinsic phase dispersion, revealing important phase information during interactions among free-space light, nanostructure, and SPs. The proposed approach is confirmed by both simulation and experiment. Then we design novel plasmonic interferometer structure for sensitive optical sensing applications. To overcome two major limitations suffered by previously reported double-slit plasmonic Mach-Zehnder interferometer (PMZI), two new schemes are proposed and investigated. (1) A PMZI based on end-fire coupling improves the SP coupling efficiency and enhance the interference contrast more than 50 times. (2) In another design, a multi-layered metal-insulator-metal PMZI releases the requirement for single-slit illumination, which enables sensitive, high-throughput sensing applications based on intensity modulation. We develop a sensitive, low-cost and high-throughput biosensing platform based on intensity modulation using ring-hole plasmonic interferometers. This biosensor is then integrated with cell-phone-based microscope, which is promising to develop a portable sensor for point-of-care diagnostics, epidemic disease control and food safety monitoring.

  19. Wideband optical vector network analyzer based on optical single-sideband modulation and optical frequency comb.

    Science.gov (United States)

    Xue, Min; Pan, Shilong; He, Chao; Guo, Ronghui; Zhao, Yongjiu

    2013-11-15

    A novel approach to increase the measurement range of the optical vector network analyzer (OVNA) based on optical single-sideband (OSSB) modulation is proposed and experimentally demonstrated. In the proposed system, each comb line in an optical frequency comb (OFC) is selected by an optical filter and used as the optical carrier for the OSSB-based OVNA. The frequency responses of an optical device-under-test (ODUT) are thus measured channel by channel. Because the comb lines in the OFC have fixed frequency spacing, by fitting the responses measured in all channels together, the magnitude and phase responses of the ODUT can be accurately achieved in a large range. A proof-of-concept experiment is performed. A measurement range of 105 GHz and a resolution of 1 MHz is achieved when a five-comb-line OFC with a frequency spacing of 20 GHz is applied to measure the magnitude and phase responses of a fiber Bragg grating.

  20. Optical and electrical effects of plasmonic nanoparticles in high-efficiency hybrid solar cells.

    Science.gov (United States)

    Fu, Wei-Fei; Chen, Xiaoqiang; Yang, Xi; Wang, Ling; Shi, Ye; Shi, Minmin; Li, Han-Ying; Jen, Alex K-Y; Chen, Jun-Wu; Cao, Yong; Chen, Hong-Zheng

    2013-10-28

    Plasmonics have been proven to be an effective way to harness more incident light to achieve high efficiency in photovoltaic devices. Herein, we explore the possibility that plasmonics can be utilized to enhance light trapping and power conversion efficiency (PCE) for polymer-quantum dot (QD) hybrid solar cells (HSCs). Based on a low band-gap polymer poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b']-dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (PCPDTBT) and a CdSe QD bulk-heterojunction (BHJ) system, gold nanoparticles were doped at different locations of the devices. Successfully, an improved PCE of 3.20 ± 0.22% and 3.16 ± 0.15% was achieved by doping the hole transporting layer and the active layer, respectively, which are among the highest values reported for CdSe QD based HSCs. A detailed study of processing, characterization, microscopy, and device fabrication is conducted to understand the underlying mechanism for the enhanced device performance. The success of this work provides a simple and generally applicable approach to enhance light harnessing of polymer-QD hybrid solar cells.

  1. Plasmonics theory and applications

    CERN Document Server

    Shahbazyan, Tigran V

    2014-01-01

    This contributed volume summarizes recent theoretical developments in plasmonics and its applications in physics, chemistry, materials science, engineering, and medicine. It focuses on recent advances in several major areas of plasmonics including plasmon-enhanced spectroscopies, light scattering, many-body effects, nonlinear optics, and ultrafast dynamics. The theoretical and computational methods used in these investigations include electromagnetic calculations, density functional theory calculations, and nonequilibrium electron dynamics calculations. The book presents a comprehensive overview of these methods as well as their applications to various current problems of interest.

  2. 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.

  3. Smart SERS Hot Spots: Single Molecules Can Be Positioned in a Plasmonic Nanojunction Using Host-Guest Chemistry.

    Science.gov (United States)

    Kim, Nam Hoon; Hwang, Wooseup; Baek, Kangkyun; Rohman, Md Rumum; Kim, Jeehong; Kim, Hyun Woo; Mun, Jungho; Lee, So Young; Yun, Gyeongwon; Murray, James; Ha, Ji Won; Rho, Junsuk; Moskovits, Martin; Kim, Kimoon

    2018-04-04

    Single-molecule surface-enhanced Raman spectroscopy (SERS) offers new opportunities for exploring the complex chemical and biological processes that cannot be easily probed using ensemble techniques. However, the ability to place the single molecule of interest reliably within a hot spot, to enable its analysis at the single-molecule level, remains challenging. Here we describe a novel strategy for locating and securing a single target analyte in a SERS hot spot at a plasmonic nanojunction. The "smart" hot spot was generated by employing a thiol-functionalized cucurbit[6]uril (CB[6]) as a molecular spacer linking a silver nanoparticle to a metal substrate. This approach also permits one to study molecules chemically reluctant to enter the hot spot, by conjugating them to a moiety, such as spermine, that has a high affinity for CB[6]. The hot spot can accommodate at most a few, and often only a single, analyte molecule. Bianalyte experiments revealed that one can reproducibly treat the SERS substrate such that 96% of the hot spots contain a single analyte molecule. Furthermore, by utilizing a series of molecules each consisting of spermine bound to perylene bisimide, a bright SERS molecule, with polymethylene linkers of varying lengths, the SERS intensity as a function of distance from the center of the hot spot could be measured. The SERS enhancement was found to decrease as 1 over the square of the distance from the center of the hot spot, and the single-molecule SERS cross sections were found to increase with AgNP diameter.

  4. Quantitative optical extinction-based parametric method for sizing a single core-shell Ag-Ag{sub 2}O nanoparticle

    Energy Technology Data Exchange (ETDEWEB)

    Santillan, J M J; Scaffardi, L B; Schinca, D C, E-mail: lucias@ciop.unlp.edu.ar [Centro de Investigaciones Opticas (CIOp), (CONICET La Plata-CIC) (Argentina)

    2011-03-16

    This paper develops a parametric method for determining the core radius and shell thickness in small silver-silver-oxide core-shell nanoparticles (Nps) based on single particle optical extinction spectroscopy. The method is based on the study of the relationship between plasmon peak wavelength, full width at half maximum (FWHM) and contrast of the extinction spectra as a function of core radius and shell thickness. This study reveals that plasmon peak wavelength is strongly dependent on shell thickness, whereas FWHM and contrast depend on both variables. These characteristics may be used for establishing an easy and fast stepwise procedure to size core-shell NPs from single particle absorption spectrum. The importance of the method lies in the possibility of monitoring the growth of the silver-oxide layer around small spherical silver Nps in real time. Using the electrostatic approximation of Mie theory, core-shell single particle extinction spectra were calculated for a silver particle's core size smaller than about 20 nm and different thicknesses of silver oxide around it. Analysis of the obtained curves shows a very particular characteristic of the plasmon peak of small silver-silver-oxide Nps, expressed in the fact that its position is strongly dependent on oxide thickness and weakly dependent on the core radius. Even a very thin oxide layer shifts the plasmon peak noticeably, enabling plasmon tuning with appropriate shell thickness. This characteristic, together with the behaviour of FWHM and contrast of the extinction spectra can be combined into a parametric method for sizing both core and shell of single silver Nps in a medium using only optical information. In turn, shell thickness can be related to oxygen content in the Np's surrounding media. The method proposed is applied to size silver Nps from single particle extinction spectrum. The results are compared with full optical spectrum fitting using the electrostatic approximation in Mie theory

  5. Nonponderomotive electron acceleration in ultrashort surface-plasmon fields

    Energy Technology Data Exchange (ETDEWEB)

    Racz, Peter; Dombi, Peter [Wigner Research Centre for Physics, Konkoly-Thege M. ut 29-33, H-1121 Budapest (Hungary)

    2011-12-15

    We investigate the nonponderomotive nature of ultrafast plasmonic electron acceleration in strongly decaying electromagnetic fields generated by few-cycle and single-cycle femtosecond laser pulses. We clearly identify the conditions contributing to nonponderomotive acceleration and establish fundamental scaling laws and carrier-envelope phase effects. These all-optically accelerated compact, femtosecond electron sources can be utilized in contemporary ultrafast methods.

  6. Plasmonic Films Can Easily Be Better: Rules and Recipes

    Science.gov (United States)

    2015-01-01

    High-quality materials are critical for advances in plasmonics, especially as researchers now investigate quantum effects at the limit of single surface plasmons or exploit ultraviolet- or CMOS-compatible metals such as aluminum or copper. Unfortunately, due to inexperience with deposition methods, many plasmonics researchers deposit metals under the wrong conditions, severely limiting performance unnecessarily. This is then compounded as others follow their published procedures. In this perspective, we describe simple rules collected from the surface-science literature that allow high-quality plasmonic films of aluminum, copper, gold, and silver to be easily deposited with commonly available equipment (a thermal evaporator). Recipes are also provided so that films with optimal optical properties can be routinely obtained. PMID:25950012

  7. Optical Properties of Gallium-Doped Zinc Oxide—A Low-Loss Plasmonic Material: First-Principles Theory and Experiment

    Directory of Open Access Journals (Sweden)

    Jongbum Kim

    2013-12-01

    Full Text Available Searching for better materials for plasmonic and metamaterial applications is an inverse design problem where theoretical studies are necessary. Using basic models of impurity doping in semiconductors, transparent conducting oxides (TCOs are identified as low-loss plasmonic materials in the near-infrared wavelength range. A more sophisticated theoretical study would help not only to improve the properties of TCOs but also to design further lower-loss materials. In this study, optical functions of one such TCO, gallium-doped zinc oxide (GZO, are studied both experimentally and by first-principles density-functional calculations. Pulsed-laser-deposited GZO films are studied by the x-ray diffraction and generalized spectroscopic ellipsometry. Theoretical studies are performed by the total-energy-minimization method for the equilibrium atomic structure of GZO and random phase approximation with the quasiparticle gap correction. Plasma excitation effects are also included for optical functions. This study identifies mechanisms other than doping, such as alloying effects, that significantly influence the optical properties of GZO films. It also indicates that ultraheavy Ga doping of ZnO results in a new alloy material, rather than just degenerately doped ZnO. This work is the first step to achieve a fundamental understanding of the connection between material, structural, and optical properties of highly doped TCOs to tailor those materials for various plasmonic applications.

  8. Plasmonic Encoding

    Science.gov (United States)

    2014-10-06

    Mangelson, B. F.; Schatz, G. C.; and Mirkin, C. A. “ Silver -based Nanodisk Codes,” ACS Nano, 2010, 9, 5446-5452. 6. Zhang, J.; Langille, M. R...Wei, W. D.; Zhang, H.; Schatz, G.; Boey, F.; Mirkin, C. A. “Free Standing Bimetallic Nanorings and Nanoring Arrays Made by On-Wire Lithography (OWL...Mirkin, C. A.; Marks, L. D.; Van Duyne, R. P. “Correlating the Structure and Localized Surface Plasmon Resonance of Single Silver Right Bipyramids

  9. Optically enhanced blood-brain-barrier crossing of plasmonic-active nanoparticles in preclinical brain tumor animal models

    Science.gov (United States)

    Yuan, Hsiangkuo; Wilson, Christy M.; Li, Shuqin; Fales, Andrew M.; Liu, Yang; Grant, Gerald; Vo-Dinh, Tuan

    2014-02-01

    Nanotechnology provides tremendous biomedical opportunities for cancer diagnosis, imaging, and therapy. In contrast to conventional chemotherapeutic agents where their actual target delivery cannot be easily imaged, integrating imaging and therapeutic properties into one platform facilitates the understanding of pharmacokinetic profiles, and enables monitoring of the therapeutic process in each individual. Such a concept dubbed "theranostics" potentiates translational research and improves precision medicine. One particular challenging application of theranostics involves imaging and controlled delivery of nanoplatforms across blood-brain-barrier (BBB) into brain tissues. Typically, the BBB hinders paracellular flux of drug molecules into brain parenchyma. BBB disrupting agents (e.g. mannitol, focused ultrasound), however, suffer from poor spatial confinement. It has been a challenge to design a nanoplatform not only acts as a contrast agent but also improves the BBB permeation. In this study, we demonstrated the feasibility of plasmonic gold nanoparticles as both high-resolution optical contrast agent and focalized tumor BBB permeation-inducing agent. We specifically examined the microscopic distribution of nanoparticles in tumor brain animal models. We observed that most nanoparticles accumulated at the tumor periphery or perivascular spaces. Nanoparticles were present in both endothelial cells and interstitial matrices. This study also demonstrated a novel photothermal-induced BBB permeation. Fine-tuning the irradiating energy induced gentle disruption of the vascular integrity, causing short-term extravasation of nanomaterials but without hemorrhage. We conclude that our gold nanoparticles are a powerful biocompatible contrast agent capable of inducing focal BBB permeation, and therefore envision a strong potential of plasmonic gold nanoparticle in future brain tumor imaging and therapy.

  10. Plasmonic transparent conductors

    Science.gov (United States)

    Liapis, Andreas C.; Sfeir, Matthew Y.; Black, Charles T.

    2016-09-01

    Many of today's technological applications, such as solar cells, light-emitting diodes, displays, and touch screens, require materials that are simultaneously optically transparent and electrically conducting. Here we explore transparent conductors based on the excitation of surface plasmons in nanostructured metal films. We measure both the optical and electrical properties of films perforated with nanometer-scale features and optimize the design parameters in order to maximize optical transmission without sacrificing electrical conductivity. We demonstrate that plasmonic transparent conductors can out-perform indium tin oxide in terms of both their transparency and their conductivity.

  11. Thin metal bilayer for surface plasmon resonance sensors in a multimode plastic optical fiber: the case of palladium and gold metal films

    Science.gov (United States)

    Cennamo, Nunzio; Zuppella, Paola; Bacco, Davide; Corso, Alain J.; Pelizzo, Maria G.; Pesavento, Maria; Zeni, Luigi

    2016-05-01

    A novel sensing platform based on thin metal bilayer for surface plasmon resonance (SPR) in a D-shaped plastic optical fiber (POF) has been designed, implemented and tested. The experimental results are congruent with the numerical studies. This platform has been properly optimized to work in the 1.38 -1.42 refractive index range and it exhibits excellent sensitivity. This refractive index range is very interesting for bio-chemical applications, where the polymer layer are used as receptors (e.g. molecularly imprinted polymer) or to immobilize the bio-receptor on the metal surface. The proposed metallic bilayer is based on palladium and gold films and replaces the traditional gold by exhibiting higher performances. Furthermore, the deposition of the thin bilayer is a single process and no further manufacturing step is required. In fact, in this case the photoresist buffer layer between the POF core and the metal layer, usually required to increase the refractive index range, is no longer necessary.

  12. Synthesis of immunotargeted magneto-plasmonic nanoclusters.

    Science.gov (United States)

    Wu, Chun-Hsien; Sokolov, Konstantin

    2014-08-22

    Magnetic and plasmonic properties combined in a single nanoparticle provide a synergy that is advantageous in a number of biomedical applications including contrast enhancement in novel magnetomotive imaging modalities, simultaneous capture and detection of circulating tumor cells (CTCs), and multimodal molecular imaging combined with photothermal therapy of cancer cells. These applications have stimulated significant interest in development of protocols for synthesis of magneto-plasmonic nanoparticles with optical absorbance in the near-infrared (NIR) region and a strong magnetic moment. Here, we present a novel protocol for synthesis of such hybrid nanoparticles that is based on an oil-in-water microemulsion method. The unique feature of the protocol described herein is synthesis of magneto-plasmonic nanoparticles of various sizes from primary blocks which also have magneto-plasmonic characteristics. This approach yields nanoparticles with a high density of magnetic and plasmonic functionalities which are uniformly distributed throughout the nanoparticle volume. The hybrid nanoparticles can be easily functionalized by attaching antibodies through the Fc moiety leaving the Fab portion that is responsible for antigen binding available for targeting.

  13. Kinetic analysis of a monoclonal therapeutic antibody and its single-chain homolog by surface plasmon resonance.

    Science.gov (United States)

    Patel, Rekha; Andrien, Bruce A

    2010-01-01

    Monoclonal antibodies (mAbs) and antibody fragments have become an emerging class of therapeutics since 1986. Their versatility enables them to be engineered for optimal efficiency and decreased immunogenicity, and the path to market has been set by recent regulatory approvals. One of the initial criteria for success of any protein or antibody therapeutic is to understand its binding characteristics to the target antigen. Surface plasmon resonance (SPR) has been widely used and is an important tool for ligand-antigen binding characterization. In this work, the binding kinetics of a recombinant mAb and its single-chain antibody homolog, single-chain variable fragment (scFv), was analyzed by SPR. These two proteins target the same antigen. The binding kinetics of the mAb (bivalent antibody) and scFv (monovalent scFv) for this antigen was analyzed along with an assessment of the thermodynamics of the binding interactions. Alternative binding configurations were investigated to evaluate potential experimental bias because theoretically experimental binding configuration should have no impact on binding kinetics. Self-association binding kinetics in the proteins' respective formulation solutions and antigen epitope mapping were also evaluated. Functional characterization of monoclonal and single-chain antibodies has become just as important as structural characterization in the biotechnology field.

  14. 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.

  15. Detection of Salmonella enteritidis Using a Miniature Optical Surface Plasmon Resonance Biosensor

    International Nuclear Information System (INIS)

    Son, J R; Kim, G; Kothapalli, A; Morgan, M T; Ess, D

    2007-01-01

    The frequent outbreaks of foodborne illness demand rapid detection of foodborne pathogens. Unfortunately, conventional methods for pathogen detection and identification are labor-intensive and take days to complete. Biosensors have shown great potential for the rapid detection of foodborne pathogens. Surface plasmon resonance (SPR) sensors have been widely adapted as an analysis tool for the study of various biological binding reactions. SPR biosensors could detect antibody-antigen bindings on the sensor surface by measuring either a resonance angle or refractive index value. In this study, the feasibility of a miniature SPR sensor (Spreeta, TI, USA) for detection of Salmonella enteritidis has been evaluated. Anti-Salmonella antibodies were immobilized on the gold sensor surface by using neutravidin. Salmonella could be detected by the Spreeta biosensor at concentrations down to 10 5 cfu/ml

  16. Model of a Plasmonic Phase Interrogation Probe for Optical Sensing of Hemoglobin in Blood Samples

    Science.gov (United States)

    Sharma, Anuj K.

    2015-11-01

    Phase interrogation based surface plasmon resonance (SPR) biosensor is proposed for the determination of Hb concentration. Previous experimental results describing variation of refractive index of human blood with Hb concentration at different wavelengths are considered for design simulations. The biosensor design with silica substrate and gold layer is considered. The sensor's performance is closely analyzed in terms of phase sensitivity and resolution. The influence of operating wavelength on biosensor's performance for Hb measurement is critically investigated, which points to carry out the Hb measurement at a shorter wavelength as phase sensitivity and resolution increase significantly with decrease in wavelength. The results are explained in terms of suitable physical concepts such as radiation damping. Use of contamination-preventing biochemical layer ascertains the stability of measurement with the intended SPR biosensor probe. The simulation results also highlight that the resolution of Hb measurement achievable with the proposed biosensor is much higher compared with several existing methods.

  17. Surface plasmon resonance investigation of optical detection in plasma-modified phospholipid layers

    International Nuclear Information System (INIS)

    Park, Byoungchoo; Cho, Chanyoun; Choi, Kyoungho; Jeon, Honggoo

    2012-01-01

    We herein report on a study of surface plasmon resonance (SPR) in thin gold (Au) films coated with thin layers of phospholipid material, which had been exposed to an atmospheric pressure (AP) plasma containing both pure Ar and Ar mixed with O 2 (Ar/O 2 , 0.8%). The phospholipid material that we used for the SPR experiments was lecithin, and the AP plasma system was applied in air by means of a radio-frequency (RF) plasma generator. A thin (∼60 nm) film of Au and a thin (∼15 nm) layer of lecithin were deposited and attached to the face of a prism, and surface plasmon modes were excited along the interfaces of the prism-Au-lecithin-air system by means of prism coupling using a He-Ne Laser (632.8 nm). The experimental SPR reflectance curves of the Au-lecithin-air modes were found to be shifted towards those of the Au-air mode with increasing applications of AP RF plasma treatment. From the shifts in the SPR curves, we found that the estimated thickness of the lecithin layer treated with a pure Ar plasma showed a linear decrease with etching rate of about 3 nm per treatment while the thickness of the lecithin layer treated with a mixed Ar/O 2 plasma showed a tendency to saturate following a large initial decrease (ca. 14 nm). All these results demonstrate that the use of SPR sensing could facilitate the detection of extremely small variations in plasma-treated films of biomaterials.

  18. Growth and characterization of nonlinear optical single crystals: bis ...

    Indian Academy of Sciences (India)

    Administrator

    molecules have received great attention for NLO applica- tions. However ... Figure 3. Single crystals of bis(cyclohexylammonium) terephthalate (crystal a) and cyclohexylammo- .... from ground state to higher energy states.17 Optical window ...

  19. Excitation of surface plasmon polariton modes with multiple nitrogen vacancy centers in single nanodiamonds

    International Nuclear Information System (INIS)

    Kumar, Shailesh; Lausen, Jens L; Andersen, Sebastian K H; Roberts, Alexander S; Radko, Ilya P; Bozhevolnyi, Sergey I; Garcia-Ortiz, Cesar E; Smith, Cameron L C; Kristensen, Anders

    2016-01-01

    Nitrogen-vacancy (NV) centers in diamonds are interesting due to their remarkable characteristics that are well suited to applications in quantum-information processing and magnetic field sensing, as well as representing stable fluorescent sources. Multiple NV centers in nanodiamonds (NDs) are especially useful as biological fluorophores due to their chemical neutrality, brightness and room-temperature photostability. Furthermore, NDs containing multiple NV centers also have potential in high-precision magnetic field and temperature sensing. Coupling NV centers to propagating surface plasmon polariton (SPP) modes gives a base for lab-on-a-chip sensing devices, allows enhanced fluorescence emission and collection which can further enhance the precision of NV-based sensors. Here, we investigate coupling of multiple NV centers in individual NDs to the SPP modes supported by silver surfaces protected by thin dielectric layers and by gold V-grooves (VGs) produced via the self-terminated silicon etching. In the first case, we concentrate on monitoring differences in fluorescence spectra obtained from a source ND, which is illuminated by a pump laser, and from a scattering ND illuminated only by the fluorescence-excited SPP radiation. In the second case, we observe changes in the average NV lifetime when the same ND is characterized outside and inside a VG. Fluorescence emission from the VG terminations is also observed, which confirms the NV coupling to the VG-supported SPP modes. (paper)

  20. Excitation of surface plasmon polariton modes with multiple nitrogen vacancy centers in single nanodiamonds

    Science.gov (United States)

    Kumar, Shailesh; Lausen, Jens L.; Garcia-Ortiz, Cesar E.; Andersen, Sebastian K. H.; Roberts, Alexander S.; Radko, Ilya P.; Smith, Cameron L. C.; Kristensen, Anders; Bozhevolnyi, Sergey I.

    2016-02-01

    Nitrogen-vacancy (NV) centers in diamonds are interesting due to their remarkable characteristics that are well suited to applications in quantum-information processing and magnetic field sensing, as well as representing stable fluorescent sources. Multiple NV centers in nanodiamonds (NDs) are especially useful as biological fluorophores due to their chemical neutrality, brightness and room-temperature photostability. Furthermore, NDs containing multiple NV centers also have potential in high-precision magnetic field and temperature sensing. Coupling NV centers to propagating surface plasmon polariton (SPP) modes gives a base for lab-on-a-chip sensing devices, allows enhanced fluorescence emission and collection which can further enhance the precision of NV-based sensors. Here, we investigate coupling of multiple NV centers in individual NDs to the SPP modes supported by silver surfaces protected by thin dielectric layers and by gold V-grooves (VGs) produced via the self-terminated silicon etching. In the first case, we concentrate on monitoring differences in fluorescence spectra obtained from a source ND, which is illuminated by a pump laser, and from a scattering ND illuminated only by the fluorescence-excited SPP radiation. In the second case, we observe changes in the average NV lifetime when the same ND is characterized outside and inside a VG. Fluorescence emission from the VG terminations is also observed, which confirms the NV coupling to the VG-supported SPP modes.

  1. Plasmonic computing of spatial differentiation

    Science.gov (United States)

    Zhu, Tengfeng; Zhou, Yihan; Lou, Yijie; Ye, Hui; Qiu, Min; Ruan, Zhichao; Fan, Shanhui

    2017-05-01

    Optical analog computing offers high-throughput low-power-consumption operation for specialized computational tasks. Traditionally, optical analog computing in the spatial domain uses a bulky system of lenses and filters. Recent developments in metamaterials enable the miniaturization of such computing elements down to a subwavelength scale. However, the required metamaterial consists of a complex array of meta-atoms, and direct demonstration of image processing is challenging. Here, we show that the interference effects associated with surface plasmon excitations at a single metal-dielectric interface can perform spatial differentiation. And we experimentally demonstrate edge detection of an image without any Fourier lens. This work points to a simple yet powerful mechanism for optical analog computing at the nanoscale.

  2. Plasmonic computing of spatial differentiation.

    Science.gov (United States)

    Zhu, Tengfeng; Zhou, Yihan; Lou, Yijie; Ye, Hui; Qiu, Min; Ruan, Zhichao; Fan, Shanhui

    2017-05-19

    Optical analog computing offers high-throughput low-power-consumption operation for specialized computational tasks. Traditionally, optical analog computing in the spatial domain uses a bulky system of lenses and filters. Recent developments in metamaterials enable the miniaturization of such computing elements down to a subwavelength scale. However, the required metamaterial consists of a complex array of meta-atoms, and direct demonstration of image processing is challenging. Here, we show that the interference effects associated with surface plasmon excitations at a single metal-dielectric interface can perform spatial differentiation. And we experimentally demonstrate edge detection of an image without any Fourier lens. This work points to a simple yet powerful mechanism for optical analog computing at the nanoscale.

  3. A generalized non-local optical response theory for plasmonic nanostructures

    DEFF Research Database (Denmark)

    Mortensen, N. Asger; Raza, Søren; Wubs, Martijn

    2014-01-01

    for their description. Here instead we present a comparatively simple semiclassical generalized non-local optical response theory that unifies quantum pressure convection effects and induced charge diffusion kinetics, with a concomitant complex-valued generalized non-local optical response parameter. Our theory...

  4. Plasmon-Assisted Selective and Super-Resolving Excitation of Individual Quantum Emitters on a Metal Nanowire.

    Science.gov (United States)

    Li, Qiang; Pan, Deng; Wei, Hong; Xu, Hongxing

    2018-03-14

    Hybrid systems composed of multiple quantum emitters coupled with plasmonic waveguides are promising building blocks for future integrated quantum nanophotonic circuits. The techniques that can super-resolve and selectively excite contiguous quantum emitters in a diffraction-limited area are of great importance for studying the plasmon-mediated interaction between quantum emitters and manipulating the single plasmon generation and propagation in plasmonic circuits. Here we show that multiple quantum dots coupled with a silver nanowire can be controllably excited by tuning the interference field of surface plasmons on the nanowire. Because of the period of the interference pattern is much smaller than the diffraction limit, we demonstrate the selective excitation of two quantum dots separated by a distance as short as 100 nm. We also numerically demonstrate a new kind of super-resolution imaging method that combines the tunable surface plasmon interference pattern on the NW with the structured illumination microscopy technique. Our work provides a novel high-resolution optical excitation and imaging method for the coupled systems of multiple quantum emitters and plasmonic waveguides, which adds a new tool for studying and manipulating single quantum emitters and single plasmons for quantum plasmonic circuitry applications.

  5. Covariant single-hole optical potential

    International Nuclear Information System (INIS)

    Kam, J. de

    1982-01-01

    In this investigation a covariant optical potential model is constructed for scattering processes of mesons from nuclei in which the meson interacts repeatedly with one of the target nucleons. The nuclear binding interactions in the intermediate scattering state are consistently taken into account. In particular for pions and K - projectiles this is important in view of the strong energy dependence of the elementary projectile-nucleon amplitude. Furthermore, this optical potential satisfies unitarity and relativistic covariance. The starting point in our discussion is the three-body model for the optical potential. To obtain a practical covariant theory I formulate the three-body model as a relativistic quasi two-body problem. Expressions for the transition interactions and propagators in the quasi two-body equations are found by imposing the correct s-channel unitarity relations and by using dispersion integrals. This is done in such a way that the correct non-relativistic limit is obtained, avoiding clustering problems. Corrections to the quasi two-body treatment from the Pauli principle and the required ground-state exclusion are taken into account. The covariant equations that we arrive at are amenable to practical calculations. (orig.)

  6. Holograms for laser diode: Single mode optical fiber coupling

    Science.gov (United States)

    Fuhr, P. L.

    1982-01-01

    The low coupling efficiency of semiconductor laser emissions into a single mode optical fibers place a severe restriction on their use. Associated with these conventional optical coupling techniques are stringent alignment sensitivities. Using holographic elements, the coupling efficiency may be increased and the alignment sensitivity greatly reduced. Both conventional and computer methods used in the generation of the holographic couplers are described and diagrammed. The reconstruction geometries used are shown to be somewhat restrictive but substantially less rigid than their conventional optical counterparts. Single and double hologram techniques are examined concerning their respective ease of fabrication and relative merits.

  7. Near field plasmon and force microscopy

    NARCIS (Netherlands)

    de Hollander, R.B.G.; van Hulst, N.F.; Kooyman, R.P.H.

    1995-01-01

    A scanning plasmon near field optical microscope (SPNM) is presented which combines a conventional far field surface plasmon microscope with a stand-alone atomic force microscope (AFM). Near field plasmon and force images are recorded simultaneously both with a lateral resolution limited by the

  8. Robustness of plasmonic angular momentum confinement in cross resonant optical antennas

    Energy Technology Data Exchange (ETDEWEB)

    Klaer, Peter; Lehr, Martin; Krewer, Keno; Schertz, Florian; Schönhense, Gerd; Elmers, Hans Joachim, E-mail: elmers@uni-mainz.de [Institut für Physik, Johannes Gutenberg-Universität, Staudingerweg 7, D-55099 Mainz (Germany); Razinskas, Gary; Wu, Xiao-Fei; Hecht, Bert [Institut für Physik, Julius-Maximilians-Universität, Am Hubland, 97074 Würzburg (Germany)

    2015-06-29

    Using a combination of photoemission electron microscopy and numerical simulations, we investigated the angular moment transfer in strongly enhanced optical near-fields of artificially fabricated optical antennas. The polarization dependence of the optical near-field enhancement has been measured in a maximum symmetric geometry, i.e., excitation by a normal incident planar wave. Finite-difference time-domain simulations for the realistic antenna geometries as determined by high-resolution electron microscopy reveal a very good agreement with experimental data. The agreement confirms that the geometrical asymmetries and inhomogeneities due to the nanoscale fabrication process preserve the circular polarization in the gap regions with strong near-field enhancement.

  9. Optimization and photomodification of extremely broadband optical response of plasmonic core-shell obscurants.

    Science.gov (United States)

    de Silva, Vashista C; Nyga, Piotr; Drachev, Vladimir P

    2016-12-15

    Plasmonic resonances of the metallic shells depend on their nanostructure and geometry of the core, which can be optimized for the broadband extinction normalized by mass. The fractal nanostructures can provide a broadband extinction. It allows as well for a laser photoburning of holes in the extinction spectra and consequently windows of transparency in a controlled manner. The studied core-shell microparticles synthesized using colloidal chemistry consist of gold fractal nanostructures grown on precipitated calcium carbonate (PCC) microparticles or silica (SiO 2 ) microspheres. The optimization includes different core sizes and shapes, and shell nanostructures. It shows that the rich surface of the PCC flakes is the best core for the fractal shells providing the highest mass normalized extinction over the extremely broad spectral range. The mass normalized extinction cross section up to 3m 2 /g has been demonstrated in the broad spectral range from the visible to mid-infrared. Essentially, the broadband response is a characteristic feature of each core-shell microparticle in contrast to a combination of several structures resonant at different wavelengths, for example nanorods with different aspect ratios. The photomodification at an IR wavelength makes the window of transparency at the longer wavelength side. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Interaction of solitary pulses in single mode optical fibres | Usman ...

    African Journals Online (AJOL)

    Two solitary waves launched, by way of incidence, into an optical fibre from a single pulse if the pulses are in-phase as understood from results of inverse scattering transform method applied to the cubic nonlinear Schrödinger equations, (CNLSE\\'s). The single CNLSE is then understood to describe evolution of coupled ...

  11. Controlled coupling of NV defect centers to plasmonic and photonic nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Barth, Michael, E-mail: michael.barth@physik.hu-berlin.d [Institute of Physics, Humboldt-Universitaet zu Berlin, Hausvogteiplatz 5-7, D-10117 Berlin (Germany); Schietinger, Stefan; Schroeder, Tim; Aichele, Thomas; Benson, Oliver [Institute of Physics, Humboldt-Universitaet zu Berlin, Hausvogteiplatz 5-7, D-10117 Berlin (Germany)

    2010-09-15

    Nitrogen-vacancy (NV) defect centers in diamond have recently emerged as promising candidates for a number of applications in the fields of quantum optics and quantum information, such as single photon generation and spin qubit operations. The performance of these defect centers can strongly be enhanced through coupling to plasmonic and photonic nanostructures, such as metal particles and optical microcavities. Here, we demonstrate the controlled assembly of such hybrid structures via manipulation with scanning near-field probes. In particular, we investigate the plasmonic enhancement of the single photon emission through coupling to gold nanospheres as well as the coupling of diamond nanocrystals to the optical modes of microsphere resonators and photonic crystal cavities. These systems represent prototypes of fundamental nanophotonic/plasmonic elements and provide control on the generation and coherent transfer of photons on the level of a single quantum emitter.

  12. Nanofocusing in a tapered graphene plasmonic waveguide

    DEFF Research Database (Denmark)

    Dai, Yunyun; Zhu, Xiaolong; Mortensen, N. Asger

    2015-01-01

    Gated or doped graphene can support plasmons making it a promising plasmonic material in the terahertz regime. Here, we show numerically that in a tapered graphene plasmonic waveguide mid- and far-infrared light can be focused in nanometer scales, far beyond the diffraction limit. The underlying...... physics lies in that when propagating along the direction towards the tip both the group and phase velocities of the plasmons supported by the tapered graphene waveguide are reduced accordingly, eventually leading to nanofocusing at the tip with a huge enhancement of optical fields. The nanofocusing...... of optical fields in tapered graphene plasmonic waveguides could be potentially exploited in the enhancement of light–matter interactions....

  13. Dynamics of coupled plasmon polariton wave packets excited at a subwavelength slit in optically thin metal films

    Science.gov (United States)

    Wang, Lei-Ming; Zhang, Lingxiao; Seideman, Tamar; Petek, Hrvoje

    2012-10-01

    We study by numerical simulations the excitation and propagation dynamics of coupled surface plasmon polariton (SPP) wave packets (WPs) in optically thin Ag films and a bulk Ag/vacuum interface under the illumination of a subwavelength slit by 400 nm continuous wave (cw) and femtosecond pulsed light. The generated surface fields include contributions from both SPPs and quasicylindrical waves, which dominate in different regimes. We explore aspects of the coupled SPP modes in Ag thin films, including symmetry, propagation, attenuation, and the variation of coupling with incident angle and film thickness. Simulations of the electromagnetic transients initiated with femtosecond pulses reveal new features of coupled SPP WP generation and propagation in thin Ag films. Our results show that, under pulsed excitation, the SPP modes in an Ag thin film break up into two distinct bound surface wave packets characterized by marked differences in symmetries, group velocities, attenuation lengths, and dispersion properties. The nanometer spatial and femtosecond temporal scale excitation and propagation dynamics of the coupled SPP WPs are revealed in detail by movies recording the evolution of their transient field distributions.

  14. Optical properties of a single free standing nanodiamond

    Energy Technology Data Exchange (ETDEWEB)

    Sun, K W; Wang, C Y [Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University, Hsinchu, 300, Taiwan (China)

    2007-12-15

    We report the techniques for measuring optical properties of a single nanometer-sized diamond. The electron beam (e-beam) lithography defined coordination markers on a silicon wafer provide us a convenient tool for allocating a single nanodiamond immobilized on the surface. By combining a confocal microscope with the e-beam lithography patterned smart substrate, we are able to measure the Raman and photoluminescence spectra from a single nanodiamond with a size less than 100 nm.

  15. Optical properties of a single free standing nanodiamond

    International Nuclear Information System (INIS)

    Sun, K W; Wang, C Y

    2007-01-01

    We report the techniques for measuring optical properties of a single nanometer-sized diamond. The electron beam (e-beam) lithography defined coordination markers on a silicon wafer provide us a convenient tool for allocating a single nanodiamond immobilized on the surface. By combining a confocal microscope with the e-beam lithography patterned smart substrate, we are able to measure the Raman and photoluminescence spectra from a single nanodiamond with a size less than 100 nm

  16. Optical Microcavity: Sensing down to Single Molecules and Atoms

    Directory of Open Access Journals (Sweden)

    Shu-Yu Su

    2011-02-01

    Full Text Available This review article discusses fundamentals of dielectric, low-loss, optical micro-resonator sensing, including figures of merit and a variety of microcavity designs, and future perspectives in microcavity-based optical sensing. Resonance frequency and quality (Q factor are altered as a means of detecting a small system perturbation, resulting in realization of optical sensing of a small amount of sample materials, down to even single molecules. Sensitivity, Q factor, minimum detectable index change, noises (in sensor system components and microcavity system including environments, microcavity size, and mode volume are essential parameters to be considered for optical sensing applications. Whispering gallery mode, photonic crystal, and slot-type microcavities typically provide compact, high-quality optical resonance modes for optical sensing applications. Surface Bloch modes induced on photonic crystals are shown to be a promising candidate thanks to large field overlap with a sample and ultra-high-Q resonances. Quantum optics effects based on microcavity quantum electrodynamics (QED would provide novel single-photo-level detection of even single atoms and molecules via detection of doublet vacuum Rabi splitting peaks in strong coupling.

  17. Optical Switching Using Transition from Dipolar to Charge Transfer Plasmon Modes in Ge2Sb2Te5 Bridged Metallodielectric Dimers

    Science.gov (United States)

    Ahmadivand, Arash; Gerislioglu, Burak; Sinha, Raju; Karabiyik, Mustafa; Pala, Nezih

    2017-02-01

    Capacitive coupling and direct shuttling of charges in nanoscale plasmonic components across a dielectric spacer and through a conductive junction lead to excitation of significantly different dipolar and charge transfer plasmon (CTP) resonances, respectively. Here, we demonstrate the excitation of dipolar and CTP resonant modes in metallic nanodimers bridged by phase-change material (PCM) sections, material and electrical characteristics of which can be controlled by external stimuli. Ultrafast switching (in the range of a few nanoseconds) between amorphous and crystalline phases of the PCM section (here Ge2Sb2Te5 (GST)) allows for designing a tunable plasmonic switch for optical communication applications with significant modulation depth (up to 88%). Judiciously selecting the geometrical parameters and taking advantage of the electrical properties of the amorphous phase of the GST section we adjusted the extinction peak of the dipolar mode at the telecommunication band (λ~1.55 μm), which is considered as the OFF state. Changing the GST phase to crystalline via optical heating allows for direct transfer of charges through the junction between nanodisks and formation of a distinct CTP peak at longer wavelengths (λ~1.85 μm) far from the telecommunication wavelength, which constitutes the ON state.

  18. Fiber optic hydrogen gas sensor utilizing surface plasmon resonance and native defects of zinc oxide by palladium

    International Nuclear Information System (INIS)

    Tabassum, Rana; Gupta, Banshi D

    2016-01-01

    We present an experimental study on a surface plasmon resonance (SPR) based fiber optic hydrogen gas sensor employing a palladium doped zinc oxide nanocomposite (ZnO (1−x) Pd x , 0 ≤ x ≤ 0.85) layer over the silver coated unclad core of the fiber. Palladium doped zinc oxide nanocomposites (ZnO (1−x) Pd x )  are prepared by a chemical route for different composition ratios and their structural, morphological and hydrogen sensing properties are investigated experimentally. The sensing principle involves the absorption of hydrogen gas by ZnO (1−x) Pd x , altering its dielectric function. The change in the dielectric constant is analyzed in terms of the red shift of the resonance wavelength in the visible region of the electromagnetic spectrum. To check the sensing capability of sensing probes fabricated with varying composition ratio (x) of nanocomposite, the SPR curves are recorded typically for 0% H 2 and 4% H 2 in N 2 atmosphere for each fabricated probe. On changing the concentration of hydrogen gas from 0% to 4%, the red shift in the SPR spectrum confirms the change in dielectric constant of ZnO (1−x) Pd x on exposure to hydrogen gas. It is noted that the shift in the SPR spectrum increases monotonically up to a certain fraction of Pd in zinc oxide, beyond which it starts decreasing. SEM images and the photoluminescence (PL) spectra reveal that Pd dopant atoms substitutionally incorporated into the ZnO lattice profoundly affect its defect levels; this is responsible for the optimal composition of ZnO (1−x) Pd x to sense the hydrogen gas. The sensor is highly selective to hydrogen gas and possesses high sensitivity. Since optical fiber sensing technology is employed along with the SPR technique, the present sensor is capable of remote sensing and online monitoring of hydrogen gas. (paper)

  19. Plasmonic Dimer Metamaterials and Metasurfaces for Polarization Control of Terahertz and Optical Waves

    DEFF Research Database (Denmark)

    Zhukovsky, Sergei; Zalkovskij, Maksim; Malureanu, Radu

    2013-01-01

    We explore the capabilities of planar metamaterials and metasurfaces to control and transform the polarization of electromagnetic radiation, and present a detailed covariant multipole theory of dimer-based metamaterials. We show that various optical properties, such as optical activity, elliptical...... dichroism or polarization conversion can be achieved in metamaterials made of simple shapes, such as nanorods, just by varying their geometrical arrangement. By virtue of the Babinet principle, the proposed theory is extended to inverted structures (membranes) where rods are replaced by slots. Such free......-standing “metasurface membranes” can act as thin-film spectrally sensitive polarization shapers for THz radiation. Proof-of-principle devices (a linear polarizer and a structure with giant optical activity) are fabricated and characterized. Experimental results coincide with those of full-wave numerical simulations...

  20. Optical measuring system with an interrogator and a polymer-based single-mode fibre optic sensor system

    DEFF Research Database (Denmark)

    2017-01-01

    The present invention relates to an optical measuring system comprising a polymer-based single-mode fibre-optic sensor system (102), an optical interrogator (101), and an optical arrangement (103) interconnecting the optical interrogator (101) and the polymer-based single-mode fibre-optic sensor...... system (102). The invention further relates to an optical interrogator adapted to be connected to a polymer-based single-mode fibre-optic sensor system via an optical arrangement. The interrogator comprises a broadband light source arrangement (104) and a spectrum analysing arrangement which receives...

  1. Optical Properties of a Single Carbon Chain-Doped Silicene Nanoribbon

    Science.gov (United States)

    Lu, Dao-Bang; Song, Yu-Ling; Huang, Xiao-yu; Wang, Chong

    2018-05-01

    Using first-principles spin polarization density function theory calculations, we have studied the electronic and optical properties of zigzag-edge silicene nanoribbons (ZSiNRs) doped with a single carbon chain. Because of the doped carbon chain, there are several defect states in the band structures of ZSiNRs across the Fermi level, and the ferromagnetic ground state is metallic. The dielectric functions in all three dimensions are completely different from each other, and thus the system exhibits strong optical anisotropism. The carbon chain influenced the dielectric functions most at low energy. The first peak in the E//x direction of the dielectric spectrum exhibits a significant blueshift, and its value has changed as well. The main absorption wavelength depends on the polarization direction of the incident light, but occurs within the UV region for all polarization directions. The peaks of the energy loss spectra correspond to the trailing edges in the reflectivity spectrum, and the highest peak corresponds to a plasmon frequency. Our results could be useful for investigating nanodevices based on silicene nanoribbons.

  2. Localized surface plasmon resonance with five-branched gold nanostars in a plastic optical fiber for bio-chemical sensor implementation.

    Science.gov (United States)

    Cennamo, Nunzio; D'Agostino, Girolamo; Donà, Alice; Dacarro, Giacomo; Pallavicini, Piersandro; Pesavento, Maria; Zeni, Luigi

    2013-10-29

    In this paper a refractive index sensor based on localized surface plasmon resonance (LSPR) in a Plastic Optical Fiber (POF), is presented and experimentally tested. LSPR is achieved exploiting five-branched gold nanostars (GNS) obtained using Triton X-100 in a seed-growth synthesis. They have the uncommon feature of three localized surface plasmon resonances. The strongest LSPRs fall in two ranges, one in the 600-900 nm range (LSPR 2) and the other one in the 1,100-1,600 nm range (LSPR 3), both sensible to refractive index changes. Anyway, due to the extremely strong attenuation (>10(2) dB/m) of the employed POF in the 1,100-1,600 nm range, only LSPR 2 will be exploited for refractive index change measurements, useful for bio-chemical sensing applications, as a proof of principle of the possibility of realizing a compact, low cost and easy-to-use GNS based device.

  3. Single-photon generator for optical telecommunication wavelength

    International Nuclear Information System (INIS)

    Usuki, T; Sakuma, Y; Hirose, S; Takemoto, K; Yokoyama, N; Miyazawa, T; Takatsu, M; Arakawa, Y

    2006-01-01

    We report on the generation of single-photon pulses from a single InAs/InP quantum dot in telecommunication bands (1.3-1.55 μm: higher transmittance through an optical fiber). First we prepared InAs quantum dots on InP (0 0 1) substrates in a low-pressure MOCVD by using a so-called InP 'double-cap' procedure. The quantum dots have well-controlled photo emission wavelength in the telecommunication bands. We also developed a single-photon emitter in which quantum dots were embedded. Numerical simulation designed the emitter to realize efficient injection of the emitted photons into a single-mode optical fiber. Using a Hanbury-Brown and Twiss technique has proved that the photons through the fiber were single photons

  4. Superluminescence from an optically pumped molecular tunneling junction by injection of plasmon induced hot electrons

    Directory of Open Access Journals (Sweden)

    Kai Braun

    2015-05-01

    Full Text Available Here, we demonstrate a bias-driven superluminescent point light-source based on an optically pumped molecular junction (gold substrate/self-assembled molecular monolayer/gold tip of a scanning tunneling microscope, operating at ambient conditions and providing almost three orders of magnitude higher electron-to-photon conversion efficiency than electroluminescence induced by inelastic tunneling without optical pumping. A positive, steadily increasing bias voltage induces a step-like rise of the Stokes shifted optical signal emitted from the junction. This emission is strongly attenuated by reversing the applied bias voltage. At high bias voltage, the emission intensity depends non-linearly on the optical pump power. The enhanced emission can be modelled by rate equations taking into account hole injection from the tip (anode into the highest occupied orbital of the closest substrate-bound molecule (lower level and radiative recombination with an electron from above the Fermi level (upper level, hence feeding photons back by stimulated emission resonant with the gap mode. The system reflects many essential features of a superluminescent light emitting diode.

  5. Efficient coupling of a single diamond color center to propagating plasmonic gap modes

    DEFF Research Database (Denmark)

    Kumar, Shailesh; Huck, Alexander; Andersen, Ulrik L

    2013-01-01

    We report on coupling of a single nitrogen-vacancy (NV) center in a nanodiamond to the propagating gap mode of two parallel placed chemically grown silver nanowires. The coupled NV-center nanowire system is made by manipulating nanodiamonds and nanowires with the tip of an atomic force microscope...

  6. Omnidirectional excitation of sidewall gap-plasmons in a hybrid gold-nanoparticle/aluminum-nanopore structure

    Directory of Open Access Journals (Sweden)

    Chatdanai Lumdee

    2016-06-01

    Full Text Available The gap-plasmon resonance of a gold nanoparticle inside a nanopore in an aluminum film is investigated in polarization dependent single particle microscopy and spectroscopy. Scattering and transmission measurements reveal that gap-plasmons of this structure can be excited and observed under normal incidence excitation and collection, in contrast to the more common particle-on-a-mirror structure. Correlation of numerical simulations with optical spectroscopy suggests that a local electric field enhancement factor in excess of 50 is achieved under normal incidence excitation, with a hot-spot located near the top surface of the structure. It is shown that the strong field enhancement from this sidewall gap-plasmon mode can be efficiently excited over a broad angular range. The presented plasmonic structure lends itself to implementation in low-cost, chemically stable, easily addressable biochemical sensor arrays providing large optical field enhancement factors.

  7. Low-Cost, Fiber-Optic Hydrogen Gas Detector Using Guided-Wave, Surface-Plasmon Resonance in Chemochromic Thin Films

    International Nuclear Information System (INIS)

    Tracy, C.E.; Benson, D.K.; Haberman, D.P.; Hishmeh, G.A.; Ciszek, P.A.

    1998-01-01

    Low-cost, hydrogen-gas-leak detectors are needed for many hydrogen applications, such as hydrogen-fueled vehicles where several detectors may be required in different locations on each vehicle. A fiber-optic leak detector could be inherently safer than conventional detectors, because it would remove all detector electronics from the vicinity of potential leaks. It would also provide freedom from electromagnetic interference, a serious problem in fuel-cell-powered electric vehicles. This paper describes the design of a fiber-optic, surface-plasmon-resonance hydrogen detector, and efforts to make it more sensitive, selective, and durable. Chemochromic materials, such as tungsten oxide and certain Lanthanide hydrides, can reversibly react with hydrogen in air while exhibiting significant changes in their optical properties. Thin films of these materials applied to a sensor at the end of an optical fiber have been used to detect low concentrations of hydrogen gas in air. The coatings include a thin silver layer in which the surface plasmon is generated, a thin film of the chemochromic material, and a catalytic layer of palladium that facilitates the reaction with hydrogen. The film thickness is chosen to produce a guided-surface plasmon wave along the interface between the silver and the chemochromic material. A dichroic beam-splitter separates the reflected spectrum into a portion near the resonance and a portion away from the resonance, and directs these two portions to two separate photodiodes. The electronic ratio of these two signals cancels most of the fiber transmission noise and provides a stable hydrogen signal

  8. Generation of a single-cycle optical pulse

    International Nuclear Information System (INIS)

    Shverdin, M.Y.; Walker, D.R.; Yavuz, D.D.; Yin, G.Y.; Harris, S.E.

    2005-01-01

    We make use of coherent control of four-wave mixing to the ultraviolet as a diagnostic and describe the generation of a periodic optical waveform where the spectrum is sufficiently broad that the envelope is approximately a single-cycle in length, and where the temporal shape of this envelope may be synthesized by varying the coefficients of a Fourier series. Specifically, using seven sidebands, we report the generation of a train of single-cycle optical pulses with a pulse width of 1.6 fs, a pulse separation of 11 fs, and a peak power of 1 MW

  9. Single Molecules as Optical Probes for Structure and Dynamics

    Science.gov (United States)

    Orrit, Michel

    Single molecules and single nanoparticles are convenient links between the nanoscale world and the laboratory. We discuss the limits for their optical detection by three different methods: fluorescence, direct absorption, and photothermal detection. We briefly review some recent illustrations of qualitatively new information gathered from single-molecule signals: intermittency of the fluorescence intensity, acoustic vibrations of nanoparticles (1-100 GHz) or of extended defects in molecular crystals (0.1-1 MHz), and dynamical heterogeneity in glass-forming molecular liquids. We conclude with an outlook of future uses of single-molecule methods in physical chemistry, soft matter, and material science.

  10. Photoluminescence and nonlinear optical phenomena in plasmonic random media—A review of recent works

    International Nuclear Information System (INIS)

    Araújo, Cid B. de; Kassab, Luciana R.P.; Tolentino Dominguez, C.; Ribeiro, Sidney J.L.; Gomes, Anderson S.L.; Reyna, Albert S.

    2016-01-01

    Photoluminescence properties and nonlinear optical response of metal–dielectric nanocomposites (MDNCs)—germanate glasses, bio-cellulose membranes and colloids containing either silver (Ag) or gold (Au) nanoparticles (NPs)—are reviewed. The phenomena discussed are: i. the photoluminescence enhancement observed from rare-earth doped PbO–GeO 2 glass containing Ag NPs; ii. optical amplification at 1530 nm in RIB waveguides made with PbO–GeO 2 thin films covered with Au NPs; iii. Random Laser emission from a bio-cellulose membrane infiltrated with Rhodamine 6G and containing Ag NPs; iv. the nonlinearity management of high-order processes in colloids containing Ag NPs suspended in acetone. In all discussed cases the influence of the metallic NPs is clearly demonstrated and a procedure to control the nonlinear propagation of light beams in heterogeneous media is presented. - Highlights: • Large photoluminescence enhancement observed from rare-earth doped PbO–GeO 2 glass containing Ag NPs. • Optical amplification at 1530 nm in RIB waveguides made with PbO–GeO 2 thin films covered with Au NPs. • Random Laser emission from a bio-cellulose membrane infiltrated with Rhodamine 6G and containing Ag NPs. • The nonlinearity management of high-order processes in liquid colloids containing Ag NPs.

  11. Photoluminescence and nonlinear optical phenomena in plasmonic random media—A review of recent works

    Energy Technology Data Exchange (ETDEWEB)

    Araújo, Cid B. de, E-mail: cid@df.ufpe.br [Departamento de Física , Universidade Federal de Pernambuco, 50670-901 Recife , PE (Brazil); Kassab, Luciana R.P. [Faculdade de Tecnologia de São Paulo (FATEC-SP , CEETEPS), 01124-060 São Paulo , SP (Brazil); Tolentino Dominguez, C. [Laboratório de Óptica Biomédica e Imagem , Universidade Federal de Pernambuco , Recife 50740-530, PE (Brazil); Ribeiro, Sidney J.L. [Institute of Chemistry , São Paulo State University (UNESP), 14801-970 Araraquara , SP (Brazil); Gomes, Anderson S.L.; Reyna, Albert S. [Departamento de Física , Universidade Federal de Pernambuco, 50670-901 Recife , PE (Brazil)

    2016-01-15

    Photoluminescence properties and nonlinear optical response of metal–dielectric nanocomposites (MDNCs)—germanate glasses, bio-cellulose membranes and colloids containing either silver (Ag) or gold (Au) nanoparticles (NPs)—are reviewed. The phenomena discussed are: i. the photoluminescence enhancement observed from rare-earth doped PbO–GeO{sub 2} glass containing Ag NPs; ii. optical amplification at 1530 nm in RIB waveguides made with PbO–GeO{sub 2} thin films covered with Au NPs; iii. Random Laser emission from a bio-cellulose membrane infiltrated with Rhodamine 6G and containing Ag NPs; iv. the nonlinearity management of high-order processes in colloids containing Ag NPs suspended in acetone. In all discussed cases the influence of the metallic NPs is clearly demonstrated and a procedure to control the nonlinear propagation of light beams in heterogeneous media is presented. - Highlights: • Large photoluminescence enhancement observed from rare-earth doped PbO–GeO{sub 2} glass containing Ag NPs. • Optical amplification at 1530 nm in RIB waveguides made with PbO–GeO{sub 2} thin films covered with Au NPs. • Random Laser emission from a bio-cellulose membrane infiltrated with Rhodamine 6G and containing Ag NPs. • The nonlinearity management of high-order processes in liquid colloids containing Ag NPs.

  12. Revealing Nanostructures through Plasmon Polarimetry.

    Science.gov (United States)

    Kleemann, Marie-Elena; Mertens, Jan; Zheng, Xuezhi; Cormier, Sean; Turek, Vladimir; Benz, Felix; Chikkaraddy, Rohit; Deacon, William; Lombardi, Anna; Moshchalkov, Victor V; Vandenbosch, Guy A E; Baumberg, Jeremy J

    2017-01-24

    Polarized optical dark-field spectroscopy is shown to be a versatile noninvasive probe of plasmonic structures that trap light to the nanoscale. Clear spectral polarization splittings are found to be directly related to the asymmetric morphology of nanocavities formed between faceted gold nanoparticles and an underlying gold substrate. Both experiment and simulation show the influence of geometry on the coupled system, with spectral shifts Δλ = 3 nm from single atoms. Analytical models allow us to identify the split resonances as transverse cavity modes, tightly confined to the nanogap. The direct correlation of resonance splitting with atomistic morphology allows mapping of subnanometre structures, which is crucial for progress in extreme nano-optics involving chemistry, nanophotonics, and quantum devices.

  13. Study of Charge-Dependent Transport and Toxicity of Peptide-Functionalized Silver Nanoparticles Using Zebrafish Embryos and Single Nanoparticle Plasmonic Spectroscopy

    Science.gov (United States)

    Lee, Kerry J.; Browning, Lauren M.; Nallathamby, Prakash D.; Xu, Xiao-Hong Nancy

    2013-01-01

    Nanomaterials possess unusually high surface area-to-volume ratios, and surface-determined physicochemical properties. It is essential to understand their surface-dependent toxicity in order to rationally design biocompatible nanomaterials for a wide variety of applications. In this study, we have functionalized the surfaces of silver nanoparticles (Ag NPs, 11.7 ± 2.7 nm in diameters) with three biocompatible peptides (CALNNK, CALNNS, CALNNE) to prepare positively (Ag-CALNNK NPs+ζ), negatively (Ag-CALNNS NPs−2ζ), and more negatively charged NPs (Ag-CALNNE NPs−4ζ), respectively. Each peptide differs in a single amino acid at its C-terminus, which minimizes the effects of peptide sequences and serves as a model molecule to create positive, neutral and negative charges on the surface of the NPs at pH 4–10. We have studied their charge-dependent transport into early-developing (cleavage-stage) zebrafish embryos and their effects on embryonic development using dark-field optical microscopy and spectroscopy (DFOMS). We found that all three Ag-peptide NPs passively diffused into the embryos via their chorionic pore canals, and stayed inside the embryos throughout their entire development (120 h), showing charge-independent diffusion modes and charge-dependent diffusion coefficients. Notably, the NPs create charge-dependent toxic effects on embryonic development, showing that the Ag-CALNNK NPs+ζ (positively charged) are the most biocompatible while the Ag-CALNNE NPs–4ζ (more negatively charged) are the most toxic. By comparing with our previous studies of the same sized citrated Ag and Au NPs, the Ag-peptide NPs are much more biocompatible than the citrated Ag NPs, and nearly as biocompatible as the Au NPs, showing the dependence of nanotoxicity upon the surface charges, surface functional groups and chemical compositions of the NPs. This study also demonstrates powerful applications of single NP plasmonic spectroscopy for quantitative analysis of single NPs

  14. Direct detection of the optical field beyond single polarization mode.

    Science.gov (United States)

    Che, Di; Sun, Chuanbowen; Shieh, William

    2018-02-05

    Direct detection is traditionally regarded as a detection method that recovers only the optical intensity. Compared with coherent detection, it owns a natural advantage-the simplicity-but lacks a crucial capability of field recovery that enables not only the multi-dimensional modulation, but also the digital compensation of the fiber impairments linear with the optical field. Full-field detection is crucial to increase the capacity-distance product of optical transmission systems. A variety of methods have been investigated to directly detect the optical field of the single polarization mode, which normally sends a carrier traveling with the signal for self-coherent detection. The crux, however, is that any optical transmission medium supports at least two propagating modes (e.g. single mode fiber supports two polarization modes), and until now there is no direct detection that can recover the complete set of optical fields beyond one polarization, due to the well-known carrier fading issue after mode demultiplexing induced by the random mode coupling. To avoid the fading, direct detection receivers should recover the signal in an intensity space isomorphic to the optical field without loss of any degrees of freedom, and a bridge should be built between the field and its isomorphic space for the multi-mode field recovery. Based on this thinking, we propose, for the first time, the direct detection of dual polarization modes by a novel receiver concept, the Stokes-space field receiver (SSFR) and its extension, the generalized SSFR for multiple spatial modes. The idea is verified by a dual-polarization field recovery of a polarization-multiplexed complex signal over an 80-km single mode fiber transmission. SSFR can be applied to a much wider range of fields beyond optical communications such as coherent sensing and imaging, where simple field recovery without an extra local laser is desired for enhanced system performance.

  15. Extending Single-Molecule Microscopy Using Optical Fourier Processing

    Science.gov (United States)

    2015-01-01

    This article surveys the recent application of optical Fourier processing to the long-established but still expanding field of single-molecule imaging and microscopy. A variety of single-molecule studies can benefit from the additional image information that can be obtained by modulating the Fourier, or pupil, plane of a widefield microscope. After briefly reviewing several current applications, we present a comprehensive and computationally efficient theoretical model for simulating single-molecule fluorescence as it propagates through an imaging system. Furthermore, we describe how phase/amplitude-modulating optics inserted in the imaging pathway may be modeled, especially at the Fourier plane. Finally, we discuss selected recent applications of Fourier processing methods to measure the orientation, depth, and rotational mobility of single fluorescent molecules. PMID:24745862

  16. Tunneling Plasmonics in Bilayer Graphene.

    Science.gov (United States)

    Fei, Z; Iwinski, E G; Ni, G X; Zhang, L M; Bao, W; Rodin, A S; Lee, Y; Wagner, M; Liu, M K; Dai, S; Goldflam, M D; Thiemens, M; Keilmann, F; Lau, C N; Castro-Neto, A H; Fogler, M M; Basov, D N

    2015-08-12

    We report experimental signatures of plasmonic effects due to electron tunneling between adjacent graphene layers. At subnanometer separation, such layers can form either a strongly coupled bilayer graphene with a Bernal stacking or a weakly coupled double-layer graphene with a random stacking order. Effects due to interlayer tunneling dominate in the former case but are negligible in the latter. We found through infrared nanoimaging that bilayer graphene supports plasmons with a higher degree of confinement compared to single- and double-layer graphene, a direct consequence of interlayer tunneling. Moreover, we were able to shut off plasmons in bilayer graphene through gating within a wide voltage range. Theoretical modeling indicates that such a plasmon-off region is directly linked to a gapped insulating state of bilayer graphene, yet another implication of interlayer tunneling. Our work uncovers essential plasmonic properties in bilayer graphene and suggests a possibility to achieve novel plasmonic functionalities in graphene few-layers.

  17. Plasmonic nanoparticle chain in a light field: a resonant optical sail.

    Science.gov (United States)

    Albaladejo, Silvia; Sáenz, Juan José; Marqués, Manuel I

    2011-11-09

    Optical trapping and driving of small objects has become a topic of increasing interest in multidisciplinary sciences. We propose to use a chain made of metallic nanoparticles as a resonant light sail, attached by one end point to a transparent object and propelling it by the use of electromagnetic radiation. Driving forces exerted on the chain are theoretically studied as a function of radiation's wavelength and chain's alignments with respect to the direction of radiation. Interestingly, there is a window in the frequency spectrum in which null-torque equilibrium configuration, with minimum geometric cross section, corresponds to a maximum in the driving force.

  18. Surface plasmon resonance based fiber optic pH sensor utilizing Ag/ITO/Al/hydrogel layers.

    Science.gov (United States)

    Mishra, Satyendra K; Gupta, Banshi D

    2013-05-07

    The fabrication and characterization of a surface plasmon resonance based pH sensor using coatings of silver, ITO (In2O3:SnO2), aluminium and smart hydrogel layers over an unclad core of an optical fiber have been reported. The silver, aluminium and ITO layers were coated using a thermal evaporation technique, while the hydrogel layer was prepared using a dip-coating method. The sensor works on the principle of detecting changes in the refractive index of the hydrogel layer due to its swelling and shrinkage caused by changes in the pH of the fluid surrounding the hydrogel layer. The sensor utilizes a wavelength interrogation technique and operates in a particular window of low and high pH values. Increasing the pH value of the fluid causes swelling of the hydrogel layer, which decreases its refractive index and results in a shift of the resonance wavelength towards blue in the transmitted spectra. The thicknesses of the ITO and aluminium layers have been optimized to achieve the best performance of the sensor. The ITO layer increases the sensitivity while the aluminium layer increases the detection accuracy of the sensor. The proposed sensor possesses maximum sensitivity in comparison to the sensors reported in the literature. A negligible effect of ambient temperature in the range 25 °C to 45 °C on the performance of the sensor has been observed. The additional advantages of the sensor are short response time, low cost, probe miniaturization, probe re-usability and the capability of remote sensing.

  19. Surface plasmon resonance-based fiber-optic hydrogen gas sensor utilizing palladium supported zinc oxide multilayers and their nanocomposite.

    Science.gov (United States)

    Tabassum, Rana; Gupta, Banshi D

    2015-02-10

    We analyze surface plasmon resonance-based fiber-optic sensor for sensing of small concentrations of hydrogen gas in the visible region of the electromagnetic spectrum. One of the two probes considered has multilayers of zinc oxide (ZnO) and palladium (Pd) while the other has layer of their composite over a silver coated unclad core of the fiber. The analysis is carried out for different volume fractions of palladium nanoparticles dispersed in zinc oxide host material in the nanocomposite layer. For the analysis, a Maxwell-Garnett model is adopted for calculating the dielectric function of a ZnO:Pd nanocomposite having nanoparticles of dimensions smaller than the wavelength of radiation used. The effects of the volume fraction of the nanoparticles in the nanocomposite and the thickness of the nanocomposite layer on the figure of merit of the sensor have been studied. The film thickness of the layer and the volume fraction of nanoparticles in the ZnO:Pd nanocomposite layer have been optimized to achieve the maximum value of the figure of merit of the sensor. It has been found that the figure of merit of the sensing probe coated with ZnO:Pd nanocomposite is more than twofold of the sensing probe coated with multilayers of Pd and ZnO over a silver coated unclad core of the fiber; hence, the sensor with a nanocomposite layer works better than that with multilayers of zinc oxide and palladium. The sensor can be used for online monitoring and remote sensing of hydrogen gas.

  20. Sol-Gel Thin Films for Plasmonic Gas Sensors

    Science.gov (United States)

    Della Gaspera, Enrico; Martucci, Alessandro

    2015-01-01

    Plasmonic gas sensors are optical sensors that use localized surface plasmons or extended surface plasmons as transducing platform. Surface plasmons are very sensitive to dielectric variations of the environment or to electron exchange, and these effects have been exploited for the realization of sensitive gas sensors. In this paper, we review our research work of the last few years on the synthesis and the gas sensing properties of sol-gel based nanomaterials for plasmonic sensors. PMID:26184216

  1. An optical channel modeling of a single mode fiber

    Science.gov (United States)

    Nabavi, Neda; Liu, Peng; Hall, Trevor James

    2018-05-01

    The evaluation of the optical channel model that accurately describes the single mode fibre as a coherent transmission medium is reviewed through analytical, numerical and experimental analysis. We used the numerical modelling of the optical transmission medium and experimental measurements to determine the polarization drift as a function of time for a fixed length of fibre. The probability distribution of the birefringence vector was derived, which is associated to the 'Poole' equation. The theory and experimental evidence that has been disclosed in the literature in the context of polarization mode dispersion - Stokes & Jones formulations and solutions for key statistics by integration of stochastic differential equations has been investigated. Besides in-depth definition of the single-mode fibre-optic channel, the modelling which concerns an ensemble of fibres each with a different instance of environmental perturbation has been analysed.

  2. Optical levitation of a microdroplet containing a single quantum dot

    Science.gov (United States)

    Minowa, Yosuke; Kawai, Ryoichi; Ashida, Masaaki

    2015-03-01

    We demonstrate the optical levitation or trapping in helium gas of a single quantum dot (QD) within a liquid droplet. Bright single photon emission from the levitated QD in the droplet was observed for more than 200 s. The observed photon count rates are consistent with the value theoretically estimated from the two-photon-action cross section. This paper presents the realization of an optically levitated solid-state quantum emitter. This paper was published in Optics Letters and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: https://www.opticsinfobase.org/ol/abstract.cfm?uri=ol-40-6-906. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.

  3. Modern plasmonics

    CERN Document Server

    Maradudin, Alexei A; Barnes, William L

    2014-01-01

    Plasmonics is entering the curriculum of many universities, either as a stand alone subject, or as part of some course or courses. Nanotechnology institutes have been, and are being, established in universities, in which plasmonics is a significant topic of research. Modern Plasmonics book offers a comprehensive presentation of the properties of surface plasmon polaritons, in systems of different structures and various natures, e.g. active, nonlinear, graded, theoretical/computational and experimental techniques for studying them, and their use in a variety of applications. Contains materia

  4. Fusion of Selected Cells and Vesicles Mediated by Optically Trapped Plasmonic Nanoparticles

    DEFF Research Database (Denmark)

    Bahadori, Azra

    . In this work, we introduce a novel and extremely flexible physical method which can trigger membrane fusion in a highly selective manner not only between synthetic GUVs of different compositions, but also between live cells which remain viable after fusion. Optical tweezers’ laser (1064 nm) is used to position....... The concept of cellular delivery is also known as targeted drug delivery and is quite a hot research topic internationally. Therefore, there have been efforts to develop various chemical molecules, proteins/peptides and physical approaches to trigger membrane fusion between synthetic giant unilamellar...... and merging of the two membranes results in merging the two membranes thereby completes the fusion. Complete fusion is associated with lipid mixing and lumen mixing which are both imaged by a high resolution confocal microscope. The confocal imaging enables quantification of the associated lipid mixing...

  5. Influence of skew rays on the sensitivity and signal-to-noise ratio of a fiber-optic surface-plasmon-resonance sensor: a theoretical study

    International Nuclear Information System (INIS)

    Dwivedi, Yogendra S.; Sharma, Anuj K.; Gupta, Banshi D.

    2007-01-01

    We have theoretically analyzed the influence of skew rays on the performance of a fiber-optic sensor based on surface plasmon resonance. The performance of the sensor has been evaluated in terms of its sensitivity and signal-to-noise ratio (SNR). The theoretical model for skewness dependence includes the material dispersion in fiber cores and metal layers, simultaneous excitation of skew rays, and meridional rays in the fiber core along with all guided rays launching from a collimated light source. The effect of skew rays on the SNR and the sensitivity of the sensor with two different metals has been compared. The same comparison is carried out for the different values of design parameters such as numerical aperture, fiber core diameter, and the length of the surface-plasmon-resonance (SPR)active sensing region. This detailed analysis for the effect of skewness on the SNR and the sensitivity of the sensor leads us to achieve the best possible performance from a fiber-optic SPR sensor against the skewness in the optical fiber

  6. Origin of optical non-linear response in TiN owing to excitation dynamics of surface plasmon resonance electronic oscillations

    Science.gov (United States)

    Divya, S.; Nampoori, V. P. N.; Radhakrishnan, P.; Mujeeb, A.

    2014-08-01

    TiN nanoparticles of average size 55 nm were investigated for their optical non-linear properties. During the experiment the irradiated laser wavelength coincided with the surface plasmon resonance (SPR) peak of the nanoparticle. The large non-linearity of the nanoparticle was attributed to the plasmon resonance, which largely enhanced the local field within the nanoparticle. Both open and closed aperture Z-scan experiments were performed and the corresponding optical constants were explored. The post-excitation absorption spectra revealed the interesting phenomenon of photo fragmentation leading to the blue shift in band gap and red shift in the SPR. The results are discussed in terms of enhanced interparticle interaction simultaneous with size reduction. Here, the optical constants being intrinsic constants for a particular sample change unusually with laser power intensity. The dependence of χ(3) is discussed in terms of the size variation caused by photo fragmentation. The studies proved that the TiN nanoparticles are potential candidates in photonics technology offering huge scope to study unexplored research for various expedient applications.

  7. Enhanced optical output of InGaN/GaN near-ultraviolet light-emitting diodes by localized surface plasmon of colloidal silver nanoparticles

    International Nuclear Information System (INIS)

    Hong, Sang-Hyun; Kim, Jae-Joon; Jung, Yen-Sook; Kim, Dong-Yu; Park, Seong-Ju; Kang, Jang-Won; Yim, Sang-Youp

    2015-01-01

    We report on the characteristics of localized surface plasmon (LSP)-enhanced near-ultraviolet light-emitting diodes (NUV-LEDs) fabricated by using colloidal silver (Ag) nanoparticles (NPs). Colloidal Ag NPs were deposited on the 20 nm thick p-GaN spacer layer using a spray process. The optical output power of NUV-LEDs with colloidal Ag NPs was increased by 48.7% at 20 mA compared with NUV-LEDs without colloidal Ag NPs. The enhancement was attributed to increased internal quantum efficiency caused by the resonance coupling between excitons in the multiple quantum wells and the LSPs in the Ag NPs. (paper)

  8. Dynamic optical arbitrary waveform shaping based on cascaded optical modulators of single FBG.

    Science.gov (United States)

    Chen, Jingyuan; Li, Peili

    2015-08-10

    A dynamic optical arbitrary waveform generation (O-AWG) with amplitude and phase independently controlled in optical modulators of single fiber Bragg Grating (FBG) has been proposed. This novel scheme consists of several optical modulators. In the optical modulator (O-MOD), a uniform FBG is used to filter spectral component of the input signal. The amplitude is controlled by fiber stretcher (FS) in Mach-Zehnder interference (MZI) structure through interference of two MZI arms. The phase is manipulated via the second FS in the optical modulator. This scheme is investigated by simulation. Consequently, optical pulse trains with different waveforms as well as pulse trains with nonuniform pulse intensity, pulse spacing and pulse width within each period are obtained through FSs adjustment to alter the phase shifts of signal in each O-MOD.

  9. Active resonance tuning of stretchable plasmonic structures

    DEFF Research Database (Denmark)

    Zhu, Xiaolong; Xiao, Sanshui; Mortensen, N. Asger

    2012-01-01

    Active resonance tuning is highly desired for the applications of plasmonic structures, such as optical switches and surface enhanced Raman substrates. In this paper, we demonstrate the active tunable plasmonic structures, which composed of monolayer arrays of metallic semishells with dielectric...... cores on stretchable elastic substrates. These composite structures support Bragg-type surface plasmon resonances whose frequencies are sensitive to the arrangement of the metallic semishells. Under uniaxial stretching, the lattice symmetry of these plasmonic structures can be reconfigured from...... applications of the stretch-tunable plasmonic structures in sensing, switching, and filtering....

  10. New applications of surface plasmon resonance technology

    International Nuclear Information System (INIS)

    Zhang Tianhao; Yin Meirong; Fang Zheyu; Yang Haidong; Yang Jia; Yang Huizhan; Kang Huizhen; Yang Dapeng; Lu Yanzhen

    2005-01-01

    Surface plasmon resonance technology is reviewed and its new applications in various fields are described. These fields include surface plasmon resonance sensors, near-field scanning optical microscopy, thin film optics and thickness measurement, holography, precise measurement of angles, and Q switching. (authors)

  11. Optical properties of Sulfur doped InP single crystals

    Science.gov (United States)

    El-Nahass, M. M.; Youssef, S. B.; Ali, H. A. M.

    2014-05-01

    Optical properties of InP:S single crystals were investigated using spectrophotometric measurements in the spectral range of 200-2500 nm. The absorption coefficient and refractive index were calculated. It was found that InP:S crystals exhibit allowed and forbidden direct transitions with energy gaps of 1.578 and 1.528 eV, respectively. Analysis of the refractive index in the normal dispersion region was discussed in terms of the single oscillator model. Some optical dispersion parameters namely: the dispersion energy (Ed), single oscillator energy (Eo), high frequency dielectric constant (ɛ∞), and lattice dielectric constant (ɛL) were determined. The volume and the surface energy loss functions (VELF & SELF) were estimated. Also, the real and imaginary parts of the complex conductivity were calculated.

  12. Identification and Quantification of Celery Allergens Using Fiber Optic Surface Plasmon Resonance PCR.

    Science.gov (United States)

    Daems, Devin; Peeters, Bernd; Delport, Filip; Remans, Tony; Lammertyn, Jeroen; Spasic, Dragana

    2017-07-31

    Abstract : Accurate identification and quantification of allergens is key in healthcare, biotechnology and food quality and safety. Celery ( Apium graveolens ) is one of the most important elicitors of food allergic reactions in Europe. Currently, the golden standards to identify, quantify and discriminate celery in a biological sample are immunoassays and two-step molecular detection assays in which quantitative PCR (qPCR) is followed by a high-resolution melting analysis (HRM). In order to provide a DNA-based, rapid and simple detection method suitable for one-step quantification, a fiber optic PCR melting assay (FO-PCR-MA) was developed to determine different concentrations of celery DNA (1 pM-0.1 fM). The presented method is based on the hybridization and melting of DNA-coated gold nanoparticles to the FO sensor surface in the presence of the target gene (mannitol dehydrogenase, Mtd ). The concept was not only able to reveal the presence of celery DNA, but also allowed for the cycle-to-cycle quantification of the target sequence through melting analysis. Furthermore, the developed bioassay was benchmarked against qPCR followed by HRM, showing excellent agreement ( R ² = 0.96). In conclusion, this innovative and sensitive diagnostic test could further improve food quality control and thus have a large impact on allergen induced healthcare problems.

  13. Identification and Quantification of Celery Allergens Using Fiber Optic Surface Plasmon Resonance PCR

    Directory of Open Access Journals (Sweden)

    Devin Daems

    2017-07-01

    Full Text Available Abstract: Accurate identification and quantification of allergens is key in healthcare, biotechnology and food quality and safety. Celery (Apium graveolens is one of the most important elicitors of food allergic reactions in Europe. Currently, the golden standards to identify, quantify and discriminate celery in a biological sample are immunoassays and two-step molecular detection assays in which quantitative PCR (qPCR is followed by a high-resolution melting analysis (HRM. In order to provide a DNA-based, rapid and simple detection method suitable for one-step quantification, a fiber optic PCR melting assay (FO-PCR-MA was developed to determine different concentrations of celery DNA (1 pM–0.1 fM. The presented method is based on the hybridization and melting of DNA-coated gold nanoparticles to the FO sensor surface in the presence of the target gene (mannitol dehydrogenase, Mtd. The concept was not only able to reveal the presence of celery DNA, but also allowed for the cycle-to-cycle quantification of the target sequence through melting analysis. Furthermore, the developed bioassay was benchmarked against qPCR followed by HRM, showing excellent agreement (R2 = 0.96. In conclusion, this innovative and sensitive diagnostic test could further improve food quality control and thus have a large impact on allergen induced healthcare problems.

  14. Giant plasmon excitation in single and double ionization of C{sub 60} by fast highly charged Si and O ions

    Energy Technology Data Exchange (ETDEWEB)

    Kelkar, A H; Kadhane, U; Misra, D; Tribedi, L C [Tata Institute of Fundamental Research, Colaba, Mumbai-5 (India)

    2007-09-15

    Se have investigated single and double ionization of C{sub 60} molecule in collisions with 2.33 MeV/u Si{sup q+} (q=6-14) and 3.125 MeV/u O{sup q+} (q=5-8) projectiles. The projectile charge state dependence of the single and double ionization yields of C{sub 60} are then compared to those for an ion-atom collision system using Ne gas as a target. A large difference between the gas and the cluster target behaviour was partially explained in terms of a model based on collective excitation namely the giant dipole plasmon resonance (GDPR). The qualitative agreement between the data and GDPR model prediction for single and double ionization signifies the importance of single and double plasmon excitations in the ionization process. A large deviation of the GDPR model for triple and quadruple ionization from the experimental data imply the importance of the other low impact parameter processes such as evaporation, fragmentation and a possible solid-like dynamical screening.

  15. Plasmon holographic experiments: theoretical framework

    International Nuclear Information System (INIS)

    Verbeeck, J.; Dyck, D. van; Lichte, H.; Potapov, P.; Schattschneider, P.

    2005-01-01

    A theoretical framework is described to understand the results of plasmon holography experiments leading to insight in the meaning of the experimental results and pointing out directions for future experiments. The framework is based on the formalism of mutual intensity to describe how coherence is transferred through an optical system. For the inelastic interaction with the object, an expression for the volume plasmon excitations in a free electron gas is used as a model for the behaviour of aluminium. The formalism leads to a clear graphical intuitive tool for understanding the experiments. It becomes evident that the measured coherence is solely related to the angular distribution of the plasmon scattering in the case of bulk plasmons. After describing the framework, the special case of coherence outside a spherical particle is treated and the seemingly controversial idea of a plasmon with a limited coherence length obtained from experiments is clarified

  16. Manipulation of single neutral atoms in optical lattices

    International Nuclear Information System (INIS)

    Zhang Chuanwei; Das Sarma, S.; Rolston, S. L.

    2006-01-01

    We analyze a scheme to manipulate quantum states of neutral atoms at individual sites of optical lattices using focused laser beams. Spatial distributions of focused laser intensities induce position-dependent energy shifts of hyperfine states, which, combined with microwave radiation, allow selective manipulation of quantum states of individual target atoms. We show that various errors in the manipulation process are suppressed below 10 -4 with properly chosen microwave pulse sequences and laser parameters. A similar idea is also applied to measure quantum states of single atoms in optical lattices

  17. Surface Plasmon Nanophotonics

    CERN Document Server

    Brongersma, Mark L

    2007-01-01

    The development of advanced dielectric photonic structures has enabled tremendous control over the propagation and manipulation of light. Structures such as waveguides, splitters, mixers, and resonators now play a central role in the telecommunications industry. This book will discuss an exciting new class of photonic devices, known as surface plasmon nanophotonic structures. Surface plasmons are easily accessible excitations in metals and semiconductors and involve a collective motion of the conduction electrons. These excitations can be exploited to manipulate electromagnetic waves at optical frequencies ("light") in new ways that are unthinkable in conventional dielectric structures. The field of plasmon nanophotonics is rapidly developing and impacting a wide range of areas including: electronics, photonics, chemistry, biology, and medicine. The book will highlight several exciting new discoveries that have been made, while providing a clear discussion of the underlying physics, the nanofabrication issues...

  18. Spontaneous decay of a single quantum dot coupled to a metallic slot waveguide in the presence of leaky plasmonic modes

    DEFF Research Database (Denmark)

    Chen, Yuntian; Gregersen, Niels; Nielsen, Torben Roland

    2010-01-01

    in which the metallic slot waveguide is embedded. Compared to the ideal case of a homogenous dielectric environment, the coupling efficiency of an emitter to a metallic slot waveguide is significantly reduced. We attribute the reduction to the coupling to leaky plasmonic modes. By increasing the refractive...

  19. Plasmonic, excitonic and exciton-plasmonic photoinduced nanocomposites

    Science.gov (United States)

    Bityurin, N.; Ermolaev, N.; Smirnov, A. A.; Afanasiev, A.; Agareva, N.; Koryukina, T.; Bredikhin, V.; Kamensky, V.; Pikulin, A.; Sapogova, N.

    2016-03-01

    UV irradiation of materials consisting of a polymer matrix that possesses precursors of different kinds can result in creation of nanoparticles within the irradiated domains. Such photoinduced nanocomposites are promising for photonic applications due to the strong alteration of their optical properties compared to initial non-irradiated materials. We report our results on the synthesis and investigation of plasmonic, excitonic and exciton-plasmonic photoinduced nanocomposites. Plasmonic nanocomposites contain metal nanoparticles of noble metals with a pronounced plasmon resonance. Excitonic nanocomposites possess semiconductor nanoclusters (quantum dots). We consider the CdS-Au pair because the luminescent band of CdS nanoparticles enters the plasmon resonance band of gold nanoparticles. The obtaining of such particles within the same composite materials is promising for the creation of media with exciton-plasmon resonance. We demonstrate that it is possible to choose appropriate precursor species to obtain the initially transparent poly(methyl methacrylate) (PMMA) films containing both types of these molecules either separately or together. Proper irradiation of these materials by a light-emitting diode operating at the wavelength of 365 nm provides material alteration demonstrating light-induced optical absorption and photoluminescent properties typical for the corresponding nanoparticles. Thus, an exciton-plasmonic photoinduced nanocomposite is obtained. It is important that here we use the precursors that are different from those usually employed.

  20. Finite-width plasmonic waveguides with hyperbolic multilayer cladding

    DEFF Research Database (Denmark)

    Babicheva, Viktoriia; Shalaginov, Mikhail Y.; Ishii, Satoshi

    2015-01-01

    Engineering plasmonic metamaterials with anisotropic optical dispersion enables us to tailor the properties of metamaterial-based waveguides. We investigate plasmonic waveguides with dielectric cores and multilayer metal-dielectric claddings with hyperbolic dispersion. Without using any homogeniz......Engineering plasmonic metamaterials with anisotropic optical dispersion enables us to tailor the properties of metamaterial-based waveguides. We investigate plasmonic waveguides with dielectric cores and multilayer metal-dielectric claddings with hyperbolic dispersion. Without using any...

  1. Pulse patterning effect in optical pulse division multiplexing for flexible single wavelength multiple access optical network

    Science.gov (United States)

    Jung, Sun-Young; Kim, Chang-Hun; Han, Sang-Kook

    2018-05-01

    A demand for high spectral efficiency requires multiple access within a single wavelength, but the uplink signals are significantly degraded because of optical beat interference (OBI) in intensity modulation/direct detection system. An optical pulse division multiplexing (OPDM) technique was proposed that could effectively reduce the OBI via a simple method as long as near-orthogonality is satisfied, but the condition was strict, and thus, the number of multiplexing units was very limited. We propose pulse pattern enhanced OPDM (e-OPDM) to reduce the OBI and improve the flexibility in multiple access within a single wavelength. The performance of the e-OPDM and patterning effect are experimentally verified after 23-km single mode fiber transmission. By employing pulse patterning in OPDM, the tight requirement was relaxed by extending the optical delay dynamic range. This could support more number of access with reduced OBI, which could eventually enhance a multiple access function.

  2. Quantum optics. All-optical routing of single photons by a one-atom switch controlled by a single photon.

    Science.gov (United States)

    Shomroni, Itay; Rosenblum, Serge; Lovsky, Yulia; Bechler, Orel; Guendelman, Gabriel; Dayan, Barak

    2014-08-22

    The prospect of quantum networks, in which quantum information is carried by single photons in photonic circuits, has long been the driving force behind the effort to achieve all-optical routing of single photons. We realized a single-photon-activated switch capable of routing a photon from any of its two inputs to any of its two outputs. Our device is based on a single atom coupled to a fiber-coupled, chip-based microresonator. A single reflected control photon toggles the switch from high reflection (R ~ 65%) to high transmission (T ~ 90%), with an average of ~1.5 control photons per switching event (~3, including linear losses). No additional control fields are required. The control and target photons are both in-fiber and practically identical, making this scheme compatible with scalable architectures for quantum information processing. Copyright © 2014, American Association for the Advancement of Science.

  3. Demultiplexing of OTDM-DPSK signals based on a single semiconductor optical amplifier and optical filtering

    DEFF Research Database (Denmark)

    Xu, Jing; Ding, Yunhong; Peucheret, Christophe

    2011-01-01

    We propose and demonstrate the use of a single semiconductor optical amplifier (SOA) and optical filtering to time demultiplex tributaries from an optical time division multiplexing-differential phase shift keying (OTDM-DPSK) signal. The scheme takes advantage of the fact that phase variations...... added to the target channel by cross-phase modulation from the control signal are effectively subtracted in the differential demodulation scheme employed for DPSK signals. Demultiplexing from 80 to 40 Gbit=s is demonstrated with moderate power penalty using an SOA with recovery time twice as long...

  4. Quantum sized Ag nanocluster assisted fluorescence enhancement in Tm{sup 3+}-Yb{sup 3+} doped optical fiber beyond plasmonics

    Energy Technology Data Exchange (ETDEWEB)

    Chattopadhyay, Rik; Haldar, Arindam; Paul, Mukul C.; Das, Shyamal; Bhadra, Shyamal K., E-mail: skbhadra@cgcri.res.in [Fiber Optics and Photonics Division, CSIR-Central Glass and Ceramic Research Institute, 196, Raja S. C. Mullick Road, Kolkata 700032 (India)

    2015-12-07

    We report a process for enhancing fluorescence emission from conventional rare earth ions in optical fiber by metal nanocluster (MNC) in nonresonant indirect pumping. The process is completely different from formal metal enhanced fluorescence phenomenon as the MNCs are too small in size to support localized surface plasmon and the excitation wavelength is far from plasmon resonance frequency. We used an established theory of two coupled oscillators to explain the simultaneous enhancement of Ytterbium (Yb{sup 3+}) and Thulium (Tm{sup 3+}) emission by silver (Ag) NCs under nonresonant pumping in optical fiber. The fiber is pumped with a 980 nm fiber pigtailed laser diode with input power of 20–100 mW to excite the Yb{sup 3+}. Four times enhancement of Yb{sup 3+} emission of 900–1100 nm and Tm{sup 3+} upconversion emission around 474 nm, 650 nm, and 790 nm is observed in the fiber with Ag NCs.

  5. Exact decoherence dynamics of a single-mode optical field

    International Nuclear Information System (INIS)

    An, J.-H.; Yeo Ye; Oh, C.H.

    2009-01-01

    We apply the influence-functional method of Feynman and Vernon to the study of a single-mode optical field that interacts with an environment at zero temperature. Using the coherent-state formalism of the path integral, we derive a generalized master equation for the single-mode optical field. Our analysis explicitly shows how non-Markovian effects manifest in the exact decoherence dynamics for different environmental correlation time scales. Remarkably, when these are equal to or greater than the time scale for significant change in the system, the interplay between the backaction-induced coherent oscillation and the dissipative effect of the environment causes the non-Markovian effect to have a significant impact not only on the short-time behavior but also on the long-time steady-state behavior of the system.

  6. Fabrication of single optical centres in diamond-a review

    International Nuclear Information System (INIS)

    Orwa, J.O.; Greentree, A.D.; Aharonovich, I.; Alves, A.D.C.; Van Donkelaar, J.; Stacey, A.; Prawer, S.

    2010-01-01

    Colour centres in diamond are rapidly becoming one of the leading platforms for solid-state quantum information processing applications. This is due in large part to the remarkable properties of the nitrogen-vacancy colour centre. From initial demonstrations of room-temperature single photon generation and spin single spin readout and quantum control, diamond nanocrystals are also finding application in magnetometry and biosensing. This review discusses the state of the art in the creation of isolated and small ensembles of optically active diamond defect centres, including nitrogen and nickel-related centres.

  7. The Optical Properties of Cu-Ni Nanoparticles Produced via Pulsed Laser Dewetting of Ultrathin Films: The Effect of Nanoparticle Size and Composition on the Plasmon Response

    International Nuclear Information System (INIS)

    Wu, Yeuyeng; Fowlkes, Jason Davidson; Rack, Philip D.

    2011-01-01

    Thin film Cu-Ni alloys ranging from 2-8nm were synthesized and their optical properties were measured as-deposited and after a laser treatment which dewet the films into arrays of spatially correlated nanoparticles. The resultant nanoparticle size and spacing are attributed to laser induced spinodal dewetting process. The evolution of the spinodal dewetting process is investigated as a function of the thin film composition which ultimately dictates the size distribution and spacing of the nanoparticles. The optical measurements of the copper rich alloy nanoparticles reveal a signature absorption peak suggestive of a plasmonic peak which red-shifts with increasing nanoparticle size and blue shifts and dampens with increasing nickel concentration.

  8. Validation of an optical surface plasmon resonance biosensor assay for screening (fluoro)quinolones in egg, fish and poultry

    NARCIS (Netherlands)

    Huet, A.C.; Charlier, C.; Weigel, S.; Benrejeb Godefroy, S.; Delahaut, P.

    2009-01-01

    A surface plasmon resonance biosensor immunoassay has been developed for multi-residue determination of 13 (fluoro)quinolone antibiotics in poultry meat, eggs and fish. The following performance characteristics were determined according to the guidelines laid down for screening assay validation in

  9. The validation of the parallel three-dimensional solver for analysis of optical plasmonic bi-periodic multilayer nanostructures

    DEFF Research Database (Denmark)

    Ni, X.; Liu, Z.; Boltasseva, Alexandra

    2010-01-01

    formulations are implemented using the scattering matrix algorithm for multilayer cascading. Then, by comparing the results from both formulations, it is shown that choosing an advanced fast-converging scheme could be essential for accurate and efficient modeling of plasmonic structures. Important obstacles...

  10. HNO₃-assisted polyol synthesis of ultralarge single-crystalline Ag microplates and their far propagation length of surface plasmon polariton.

    Science.gov (United States)

    Chang, Cheng-Wei; Lin, Fan-Cheng; Chiu, Chun-Ya; Su, Chung-Yi; Huang, Jer-Shing; Perng, Tsong-Pyng; Yen, Ta-Jen

    2014-07-23

    We developed a HNO3-assisted polyol reduction method to synthesize ultralarge single-crystalline Ag microplates routinely. The edge length of the synthesized Ag microplates reaches 50 μm, and their top facets are (111). The mechanism for dramatically enlarging single-crystalline Ag structure stems from a series of competitive anisotropic growths, primarily governed by carefully tuning the adsorption of Ag(0) by ethylene glycol and the desorption of Ag(0) by a cyanide ion on Ag(100). Finally, we measured the propagation length of surface plasmon polaritons along the air/Ag interface under 534 nm laser excitation. Our single-crystalline Ag microplate exhibited a propagation length (11.22 μm) considerably greater than that of the conventional E-gun deposited Ag thin film (5.27 μm).

  11. Linear optical quantum computing in a single spatial mode.

    Science.gov (United States)

    Humphreys, Peter C; Metcalf, Benjamin J; Spring, Justin B; Moore, Merritt; Jin, Xian-Min; Barbieri, Marco; Kolthammer, W Steven; Walmsley, Ian A

    2013-10-11

    We present a scheme for linear optical quantum computing using time-bin-encoded qubits in a single spatial mode. We show methods for single-qubit operations and heralded controlled-phase (cphase) gates, providing a sufficient set of operations for universal quantum computing with the Knill-Laflamme-Milburn [Nature (London) 409, 46 (2001)] scheme. Our protocol is suited to currently available photonic devices and ideally allows arbitrary numbers of qubits to be encoded in the same spatial mode, demonstrating the potential for time-frequency modes to dramatically increase the quantum information capacity of fixed spatial resources. As a test of our scheme, we demonstrate the first entirely single spatial mode implementation of a two-qubit quantum gate and show its operation with an average fidelity of 0.84±0.07.

  12. Near field plasmon and force microscopy

    OpenAIRE

    de Hollander, R.B.G.; van Hulst, N.F.; Kooyman, R.P.H.

    1995-01-01

    A scanning plasmon near field optical microscope (SPNM) is presented which combines a conventional far field surface plasmon microscope with a stand-alone atomic force microscope (AFM). Near field plasmon and force images are recorded simultaneously both with a lateral resolution limited by the probe size to about 20 nm. At variance to previous work, utilizing a scanning tunneling microscope (STM) with a metallic tip, a dielectric silicon-nitride tip is used in contact mode. This arrangement ...

  13. Radiation resistance characteristics of optical communication system for single mode

    International Nuclear Information System (INIS)

    Ohe, Masamoto; Chigusa, Yoshiki; Kyodo, Tomohisa; Tanaka, Gohtaro; Watanabe, Hajime; Okamoto, Shin-ichi; Yamamoto, Takao.

    1988-01-01

    Optical communication has been utilized also for nuclear power stations and fuel reporocessing plants. As the sufficient safety countermeasures are required there, the amount of information becomes enormous, therefore, optical communication, by which the required space is expected to be reduced, becomes more important. Also in the application to submarine cables, attention must be paid to the radiation resistance as there are the effects of potassium contained in large amount in seawater and uranium deposits in sea bottom. Therefore, the reliability of the components of optical communication systems against radiation becomes a problem. In this study, single mode optical fibers and transmission and receipt modules were selected, and high dose rate irradiation supposing the case of using in a cell and low dose rate, long time irradiation supposing the case of submarine cables were carried out to evaluate the radiation resistance characteristics. The fibers tested were SiO 2 core/F-SiO 2 clad type and GeO 2 -SiO 2 core/SiO 2 clad type. The characteristics of increasing loss in irradiation and restoration after irradiation of the former type were superior to those of the latter type. The output of a receipt module was normal during irradiation, and the output power of a transmission module decreases, but other problems did not arise. (K.I.)

  14. Electrical and optical transport properties of single layer WSe2

    Science.gov (United States)

    Tahir, M.

    2018-03-01

    The electronic properties of single layer WSe2 are distinct from the famous graphene due to strong spin orbit coupling, a huge band gap and an anisotropic lifting of the degeneracy of the valley degree of freedom under Zeeman field. In this work, band structure of the monolayer WSe2 is evaluated in the presence of spin and valley Zeeman fields to study the electrical and optical transport properties. Using Kubo formalism, an explicit expression for the electrical Hall conductivity is examined at finite temperatures. The electrical longitudinal conductivity is also evaluated. Further, the longitudinal and Hall optical conductivities are analyzed. It is observed that the contributions of the spin-up and spin-down states to the power absorption spectrum depend on the valley index. The numerical results exhibit absorption peaks as a function of photon energy, ℏ ω, in the range ∼ 1.5 -2 eV. Also, the optical response lies in the visible frequency range in contrast to the conventional two-dimensional electron gas or graphene where the response is limited to terahertz regime. This ability to isolate carriers in spin-valley coupled structures may make WSe2 a promising candidate for future spintronics, valleytronics and optical devices.

  15. Plasmonic percolation: Plasmon-manifested dielectric-to-metal transition

    KAUST Repository

    Chen, Huanjun

    2012-08-28

    Percolation generally refers to the phenomenon of abrupt variations in electrical, magnetic, or optical properties caused by gradual volume fraction changes of one component across a threshold in bicomponent systems. Percolation behaviors have usually been observed in macroscopic systems, with most studies devoted to electrical percolation. We report on our observation of plasmonic percolation in Au nanorod core-Pd shell nanostructures. When the Pd volume fraction in the shell consisting of palladium and water approaches the plasmonic percolation threshold, ∼70%, the plasmon of the nanostructure transits from red to blue shifts with respect to that of the unshelled Au nanorod. This plasmonic percolation behavior is also confirmed by the scattering measurements on the individual core-shell nanostructures. Quasistatic theory and numerical simulations show that the plasmonic percolation originates from a positive-to-negative transition in the real part of the dielectric function of the shell as the Pd volume fraction is increased. The observed plasmonic percolation is found to be independent of the metal type in the shell. Moreover, compared to the unshelled Au nanorods with similar plasmon wavelengths, the Au nanorod core-Pd shell nanostructures exhibit larger refractive index sensitivities, which is ascribed to the expulsion of the electric field intensity from the Au nanorod core by the adsorbed Pd nanoparticles. © 2012 American Chemical Society.

  16. Plasmonic percolation: Plasmon-manifested dielectric-to-metal transition

    KAUST Repository

    Chen, Huanjun; Wang, Feng; Li, Kun; Woo, Katchoi; Wang, Jianfang; Li, Quan; Sun, Ling Dong; Zhang, Xixiang; Lin, Haiqing; YAN, Chunhua

    2012-01-01

    Percolation generally refers to the phenomenon of abrupt variations in electrical, magnetic, or optical properties caused by gradual volume fraction changes of one component across a threshold in bicomponent systems. Percolation behaviors have usually been observed in macroscopic systems, with most studies devoted to electrical percolation. We report on our observation of plasmonic percolation in Au nanorod core-Pd shell nanostructures. When the Pd volume fraction in the shell consisting of palladium and water approaches the plasmonic percolation threshold, ∼70%, the plasmon of the nanostructure transits from red to blue shifts with respect to that of the unshelled Au nanorod. This plasmonic percolation behavior is also confirmed by the scattering measurements on the individual core-shell nanostructures. Quasistatic theory and numerical simulations show that the plasmonic percolation originates from a positive-to-negative transition in the real part of the dielectric function of the shell as the Pd volume fraction is increased. The observed plasmonic percolation is found to be independent of the metal type in the shell. Moreover, compared to the unshelled Au nanorods with similar plasmon wavelengths, the Au nanorod core-Pd shell nanostructures exhibit larger refractive index sensitivities, which is ascribed to the expulsion of the electric field intensity from the Au nanorod core by the adsorbed Pd nanoparticles. © 2012 American Chemical Society.

  17. Coulomb Blockade Plasmonic Switch.

    Science.gov (United States)

    Xiang, Dao; Wu, Jian; Gordon, Reuven

    2017-04-12

    Tunnel resistance can be modulated with bias via the Coulomb blockade effect, which gives a highly nonlinear response current. Here we investigate the optical response of a metal-insulator-nanoparticle-insulator-metal structure and show switching of a plasmonic gap from insulator to conductor via Coulomb blockade. By introducing a sufficiently large charging energy in the tunnelling gap, the Coulomb blockade allows for a conductor (tunneling) to insulator (capacitor) transition. The tunnelling electrons can be delocalized over the nanocapacitor again when a high energy penalty is added with bias. We demonstrate that this has a huge impact on the plasmonic resonance of a 0.51 nm tunneling gap with ∼70% change in normalized optical loss. Because this structure has a tiny capacitance, there is potential to harness the effect for high-speed switching.

  18. Optical Sensor Based on a Single CdS Nanobelt

    Directory of Open Access Journals (Sweden)

    Lei Li

    2014-04-01

    Full Text Available In this paper, an optical sensor based on a cadmium sulfide (CdS nanobelt has been developed. The CdS nanobelt was synthesized by the vapor phase transportation (VPT method. X-Ray Diffraction (XRD and Transmission Electron Microscopy (TEM results revealed that the nanobelt had a hexagonal wurtzite structure of CdS and presented good crystal quality. A single nanobelt Schottky contact optical sensor was fabricated by the electron beam lithography (EBL technique, and the device current-voltage results showed back-to-back Schottky diode characteristics. The photosensitivity, dark current and the decay time of the sensor were 4 × 104, 31 ms and 0.2 pA, respectively. The high photosensitivity and the short decay time were because of the exponential dependence of photocurrent on the number of the surface charges and the configuration of the back to back Schottky junctions.

  19. Optical sensor based on a single CdS nanobelt.

    Science.gov (United States)

    Li, Lei; Yang, Shuming; Han, Feng; Wang, Liangjun; Zhang, Xiaotong; Jiang, Zhuangde; Pan, Anlian

    2014-04-23

    In this paper, an optical sensor based on a cadmium sulfide (CdS) nanobelt has been developed. The CdS nanobelt was synthesized by the vapor phase transportation (VPT) method. X-Ray Diffraction (XRD) and Transmission Electron Microscopy (TEM) results revealed that the nanobelt had a hexagonal wurtzite structure of CdS and presented good crystal quality. A single nanobelt Schottky contact optical sensor was fabricated by the electron beam lithography (EBL) technique, and the device current-voltage results showed back-to-back Schottky diode characteristics. The photosensitivity, dark current and the decay time of the sensor were 4 × 10⁴, 31 ms and 0.2 pA, respectively. The high photosensitivity and the short decay time were because of the exponential dependence of photocurrent on the number of the surface charges and the configuration of the back to back Schottky junctions.

  20. Design methodology for all-optical bistable switches based on a plasmonic resonator sandwiched between dielectric waveguides

    International Nuclear Information System (INIS)

    Xiang, Yinxiao; Cai, Wei; Wang, Lei; Ying, Cuifeng; Zhang, Xinzheng; Xu, Jingjun

    2014-01-01

    We present a bistable device consisting of a Bragg grating resonator with a Kerr medium sandwiched between two dielectric slab waveguides. The resonator is situated in a nanometer-scaled metal–insulator–metal plasmonic waveguide. Due to the dimensional confinement from the dielectric waveguide to the nanoscaled plasmonic waveguide, electric fields are enhanced greatly, which will further reduce the threshold value. Moreover, a semi-analytic method, based on the impedance theory and the transfer matrix method, is developed to study the transmission and reflection spectra as well as the bistability loop of such a switch. Our method is fast and accurate, as confirmed by the finite-difference time-domain simulation. (invited paper)

  1. Extracting and focusing of surface plasmon polaritons inside finite asymmetric metal/insulator/metal structure at apex of optical fiber by subwavelength holes

    Science.gov (United States)

    Oshikane, Yasushi; Murai, Kensuke; Nakano, Motohiro

    2013-09-01

    We have been studied a finite asymmetric metal-insulator-metal (MIM) structure on glass plate for near-future visible light communication (VLC) system with white LED illuminations in the living space (DOI: 10.1117/12.929201). The metal layers are vacuum-evaporated thin silver (Ag) films (around 50 nm and 200 nm, respectively), and the insulator layer (around 150 nm) is composed of magnesium fluoride (MgF2). A characteristic narrow band filtering of the MIM structure at visible region might cause a confinement of intense surface plasmon polaritons (SPPs) at specific monochromatic frequency inside a subwavelength insulator layer of the MIM structure. Central wavelength and depth of such absorption dip in flat spectral reflectance curve is controlled by changing thicknesses of both insulator and thinner metal layers. On the other hand, we have proposed a twin-hole pass-through wave guide for SPPs in thick Ag film (DOI: 10.1117/12.863587). At that time, the twin-hole converted a incoming plane light wave into a pair of channel plasmon polaritons (CPPs), and united them at rear surface of the Ag film. This research is having an eye to extract, guide, and focus the SPPs through a thicker metal layer of the MIM with FIBed subwavelength pass-through holes. The expected outcome is a creation of noble, monochromatic, and tunable fiber probe for scanning near-field optical microscopes (SNOMs) with intense white light sources. Basic experimental and FEM simulation results will be presented.

  2. Investigation of change of tumor optical properties after laser-induced plasmon-resonant photothermal treatment of transplanted tumors in rats

    Science.gov (United States)

    Genin, Vadim D.; Genina, Elina A.; Bucharskaya, Alla B.; Tuchin, Valery V.; Khlebtsov, Nikolay G.; Terentyuk, Georgy S.; Bashkatov, Alexey N.

    2018-04-01

    The paper presents the investigation of change of tumor optical properties of the rat tumor doped by gold nanoparticles after laser-induced plasmon-resonant photothermal treatment. To obtain the model tumors the rats have been implanted by suspension of alveolar kidney cancer cells. An hour before the experiment the animals have been injected by the suspension of gold nanorods intratumorally. For irradiation a diode laser with wavelength 808 nm has been used. After the irradiation the tumor has been removed and sliced. Spectra of total and collimated transmission and diffuse reflectance of the samples of different layers of the tumors have been measured in the wavelength range 350-2500 nm. Absorption, scattering, reduced scattering coefficients and scattering anisotropy factor of tumor tissues have been calculated with inverse adding-doubling method. The results of the experiment have shown that after doping the tumor tissue by the plasmon resonant nanoparticles and NIR laser irradiating, there is the decreases of absorption as well as scattering properties of the tumor and surrounding tissues. However, despite the sufficiently high temperature on the surface (about 80°C), the changes in the center of the tumor are insignificant.

  3. Localized Surface Plasmon Resonance with Five-Branched Gold Nanostars in a Plastic Optical Fiber for Bio-Chemical Sensor Implementation

    Science.gov (United States)

    Cennamo, Nunzio; D'Agostino, Girolamo; Donà, Alice; Dacarro, Giacomo; Pallavicini, Piersandro; Pesavento, Maria; Zeni, Luigi

    2013-01-01

    In this paper a refractive index sensor based on localized surface plasmon resonance (LSPR) in a Plastic Optical Fiber (POF), is presented and experimentally tested. LSPR is achieved exploiting five-branched gold nanostars (GNS) obtained using Triton X-100 in a seed-growth synthesis. They have the uncommon feature of three localized surface plasmon resonances. The strongest LSPRs fall in two ranges, one in the 600–900 nm range (LSPR 2) and the other one in the 1,100–1,600 nm range (LSPR 3), both sensible to refractive index changes. Anyway, due to the extremely strong attenuation (>102 dB/m) of the employed POF in the 1,100–1,600 nm range, only LSPR 2 will be exploited for refractive index change measurements, useful for bio-chemical sensing applications, as a proof of principle of the possibility of realizing a compact, low cost and easy-to-use GNS based device. PMID:24172284

  4. Localized Surface Plasmon Resonance with Five-Branched Gold Nanostars in a Plastic Optical Fiber for Bio-Chemical Sensor Implementation

    Directory of Open Access Journals (Sweden)

    Luigi Zeni

    2013-10-01

    Full Text Available In this paper a refractive index sensor based on localized surface plasmon resonance (LSPR in a Plastic Optical Fiber (POF, is presented and experimentally tested. LSPR is achieved exploiting five-branched gold nanostars (GNS obtained using Triton X-100 in a seed-growth synthesis. They have the uncommon feature of three localized surface plasmon resonances. The strongest LSPRs fall in two ranges, one in the 600–900 nm range (LSPR 2 and the other one in the 1,100–1,600 nm range (LSPR 3, both sensible to refractive index changes. Anyway, due to the extremely strong attenuation (>102 dB/m of the employed POF in the 1,100–1,600 nm range, only LSPR 2 will be exploited for refractive index change measurements, useful for bio-chemical sensing applications, as a proof of principle of the possibility of realizing a compact, low cost and easy-to-use GNS based device.

  5. Three-dimensional scanning near field optical microscopy (3D-SNOM) imaging of random arrays of copper nanoparticles: implications for plasmonic solar cell enhancement.

    Science.gov (United States)

    Ezugwu, Sabastine; Ye, Hanyang; Fanchini, Giovanni

    2015-01-07

    In order to investigate the suitability of random arrays of nanoparticles for plasmonic enhancement in the visible-near infrared range, we introduced three-dimensional scanning near-field optical microscopy (3D-SNOM) imaging as a useful technique to probe the intensity of near-field radiation scattered by random systems of nanoparticles at heights up to several hundred nm from their surface. We demonstrated our technique using random arrays of copper nanoparticles (Cu-NPs) at different particle diameter and concentration. Bright regions in the 3D-SNOM images, corresponding to constructive interference of forward-scattered plasmonic waves, were obtained at heights Δz ≥ 220 nm from the surface for random arrays of Cu-NPs of ∼ 60-100 nm in diameter. These heights are too large to use Cu-NPs in contact of the active layer for light harvesting in thin organic solar cells, which are typically no thicker than 200 nm. Using a 200 nm transparent spacer between the system of Cu-NPs and the solar cell active layer, we demonstrate that forward-scattered light can be conveyed in 200 nm thin film solar cells. This architecture increases the solar cell photoconversion efficiency by a factor of 3. Our 3D-SNOM technique is general enough to be suitable for a large number of other applications in nanoplasmonics.

  6. Nonlinear polarization effects in a birefringent single mode optical fiber

    International Nuclear Information System (INIS)

    Ishiekwene, G.C.; Mensah, S.Y.; Brown, C.S.

    2001-04-01

    The nonlinear polarization effects in a birefringent single mode optical fiber is studied using Jacobi elliptic functions. We find that the polarization state of the propagating beam depends on the initial polarization as well as the intensity of the input light in a complicated way. The Stokes polarization parameters are either periodic or aperiodic depending on the value of the Jacobian modulus. Our calculations suggest that the effective beat length of the fiber can become infinite at a higher critical value of the input power when polarization dependent losses are considered. (author)

  7. Cavity QED with a single QD inside an optical microcavity

    International Nuclear Information System (INIS)

    Peter, E.; Bloch, J.; Lemaitre, A.; Hours, J.; Patriarche, G.; Cavanna, A.; Laurent, S.; Robert-Philip, I.; Senellart, P.; Martrou, D.; Gerard, J.M.

    2006-01-01

    To demonstrate strong coupling regime for a single quantum dot inside an optical microcavity, large oscillator strength quantum dots are needed. We show that quantum dots formed by the interface fluctuations of a thin GaAs quantum well are ideal systems for this purpose since they can present an oscillator strength larger than 100. By inserting a GaAs QD inside a state of the art microdisk microcavity, we demonstrate the strong coupling regime with a Rabi splitting of 400 μeV. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  8. A versatile optical microscope for time-dependent single-molecule and single-particle spectroscopy

    Science.gov (United States)

    Li, Hao; Yang, Haw

    2018-03-01

    This work reports the design and implementation of a multi-function optical microscope for time-dependent spectroscopy on single molecules and single nanoparticles. It integrates the now-routine single-object measurements into one standalone platform so that no reconfiguration is needed when switching between different types of sample or spectroscopy modes. The illumination modes include evanescent field through total internal reflection, dark-field illumination, and epi-excitation onto a diffraction-limited spot suitable for confocal detection. The detection modes include spectrally resolved line imaging, wide-field imaging with dual-color capability, and two-color single-element photon-counting detection. The switch between different spectroscopy and data acquisition modes is fully automated and executed through computer programming. The capability of this microscope is demonstrated through selected proof-of-principle experiments.

  9. A versatile optical microscope for time-dependent single-molecule and single-particle spectroscopy.

    Science.gov (United States)

    Li, Hao; Yang, Haw

    2018-03-28

    This work reports the design and implementation of a multi-function optical microscope for time-dependent spectroscopy on single molecules and single nanoparticles. It integrates the now-routine single-object measurements into one standalone platform so that no reconfiguration is needed when switching between different types of sample or spectroscopy modes. The illumination modes include evanescent field through total internal reflection, dark-field illumination, and epi-excitation onto a diffraction-limited spot suitable for confocal detection. The detection modes include spectrally resolved line imaging, wide-field imaging with dual-color capability, and two-color single-element photon-counting detection. The switch between different spectroscopy and data acquisition modes is fully automated and executed through computer programming. The capability of this microscope is demonstrated through selected proof-of-principle experiments.

  10. Semiconductors for plasmonics and metamaterials

    DEFF Research Database (Denmark)

    Naik, G.V.; Boltasseva, Alexandra

    2010-01-01

    Plasmonics has conventionally been in the realm of metal-optics. However, conventional metals as plasmonic elements in the near-infrared (NIR) and visible spectral ranges suffer from problems such as large losses and incompatibility with semiconductor technology. Replacing metals with semiconduct......Plasmonics has conventionally been in the realm of metal-optics. However, conventional metals as plasmonic elements in the near-infrared (NIR) and visible spectral ranges suffer from problems such as large losses and incompatibility with semiconductor technology. Replacing metals...... with semiconductors can alleviate these problems if only semiconductors could exhibit negative real permittivity. Aluminum doped zinc oxide (AZO) is a low loss semiconductor that can show negative real permittivity in the NIR. A comparative assessment of AZO-based plasmonic devices such as superlens and hyperlens...... with their metal-based counterparts shows that AZO-based devices significantly outperform at a wavelength of 1.55 µm. This provides a strong stimulus in turning to semiconductor plasmonics at the telecommunication wavelengths. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)....

  11. Light-emitting waveguide-plasmon polaritions

    NARCIS (Netherlands)

    Rodriguez, S.R.K.; Murai, S.; Verschuuren, M.A.; Gómez Rivas, J.

    2012-01-01

    We demonstrate the generation of light in an optical waveguide strongly coupled to a periodic array of metallic nanoantennas. This coupling gives rise to hybrid waveguide-plasmon polaritons (WPPs), which undergo a transmutation from plasmon to waveguide mode and vice versa as the eigenfrequency

  12. A plasmonic spanner for metal particle manipulation

    NARCIS (Netherlands)

    Zhang, Y.; Shi, W.; Shen, Z.; Man, Z.; Min, C.; Shen, J.; Zhu, S.; Urbach, H.P.; Yuan, X.

    2015-01-01

    Typically, metal particles are difficult to manipulate with conventional optical vortex (OV) tweezers, because of their strong absorption and scattering. However, it has been shown that the vortex field of surface plasmonic polaritons, called plasmonic vortex (PV), is capable of stable trapping and

  13. Controlling light with resonant plasmonic nanostructures

    NARCIS (Netherlands)

    Waele, R. de

    2009-01-01

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

  14. High efficiency all-optical plasmonic diode based on a nonlinear side-coupled waveguide-cavity structure with broken symmetry

    Science.gov (United States)

    Liang, Hong-Qin; Liu, Bin; Hu, Jin-Feng; He, Xing-Dao

    2018-05-01

    An all-optical plasmonic diode, comprising a metal-insulator-metal waveguide coupled with a stub cavity, is proposed based on a nonlinear Fano structure. The key technique used is to break structural spatial symmetry by a simple reflector layer in the waveguide. The spatial asymmetry of the structure gives rise to the nonreciprocity of coupling efficiencies between the Fano cavity and waveguides on both sides of the reflector layer, leading to a nonreciprocal nonlinear response. Transmission properties and dynamic responses are numerically simulated and investigated by the nonlinear finite-difference time-domain method. In the proposed structure, high-efficiency nonreciprocal transmission can be achieved with a low power threshold and an ultrafast response time (subpicosecond level). A high maximum transmittance of 89.3% and an ultra-high transmission contrast ratio of 99.6% can also be obtained. The device can be flexibly adjusted for working wavebands by altering the stub cavity length.

  15. Comprehensive investigation of noble metal nanoparticles shape, size and material on the optical response of optimal plasmonic Y-splitter waveguides

    Science.gov (United States)

    Ahmadivand, Arash; Golmohammadi, Saeed

    2014-01-01

    With the purpose of guiding and splitting of optical power at C-band spectrum, we studied Y-shape splitters based on various shapes of nanoparticles as a plasmon waveguide. We applied different configurations of Gold (Au) and Silver (Ag) nanoparticles including spheres, rods and rings, to optimize the efficiency and losses of two and four-branch splitters. The best performance in light transportation specifically at telecom wavelength (λ≈1550 nm) is achieved by nanorings, due to an extra degree of freedom in their geometrical components. In addition, comparisons of several values for offset distance (doffset) of examined structures shows that Au nanoring splitters with feasible lower doffset have high quality in guiding and splitting of light through the structure. Finally, we studied four-branch Y-splitters based on Au and Ag nanorings with least possible offset distances to optimize the splitter performance. The power transmission as a key element is calculated for examined structures.

  16. Plasmon Geometric Phase and Plasmon Hall Shift

    Science.gov (United States)

    Shi, Li-kun; Song, Justin C. W.

    2018-04-01

    The collective plasmonic modes of a metal comprise a simple pattern of oscillating charge density that yields enhanced light-matter interaction. Here we unveil that beneath this familiar facade plasmons possess a hidden internal structure that fundamentally alters its dynamics. In particular, we find that metals with nonzero Hall conductivity host plasmons with an intricate current density configuration that sharply departs from that of ordinary zero Hall conductivity metals. This nontrivial internal structure dramatically enriches the dynamics of plasmon propagation, enabling plasmon wave packets to acquire geometric phases as they scatter. At boundaries, these phases accumulate allowing plasmon waves that reflect off to experience a nonreciprocal parallel shift. This plasmon Hall shift, tunable by Hall conductivity as well as plasmon wavelength, displaces the incident and reflected plasmon trajectories and can be readily probed by near-field photonics techniques. Anomalous plasmon geometric phases dramatically enrich the nanophotonics toolbox, and yield radical new means for directing plasmonic beams.

  17. Optical absorption of zigzag single walled boron nitride nanotubes

    Science.gov (United States)

    Moradian, Rostam; Chegel, Raad; Behzad, Somayeh

    2010-11-01

    In a realistic three-dimensional model, optical matrix element and linear optical absorption of zigzag single walled boron nitride nanotubes (BNNTs) in the tight binding approximation are studied. In terms of absolute value of dipole matrix elements of the first three direct transitions at kz=0, we divided the zigzag BNNTs into three groups and investigated their optical absorption spectrum in energy ranges E7.5 eV. We found that in lower energies, E7.5 eV, their behaviors depend on their even or odd nanotube index. We also found that in the energy range 7

  18. Novel Plasmonic Materials and Nanodevices for Integrated Quantum Photonics

    Science.gov (United States)

    Shalaginov, Mikhail Y.

    Light-matter interaction is the foundation for numerous important quantum optical phenomena, which may be harnessed to build practical devices with higher efficiency and unprecedented functionality. Nanoscale engineering is seen as a fruitful avenue to significantly strengthen light-matter interaction and also make quantum optical systems ultra-compact, scalable, and energy efficient. This research focuses on color centers in diamond that share quantum properties with single atoms. These systems promise a path for the realization of practical quantum devices such as nanoscale sensors, single-photon sources, and quantum memories. In particular, we explored an intriguing methodology of utilizing nanophotonic structures, such as hyperbolic metamaterials, nanoantennae, and plasmonic waveguides, to improve the color centers performance. We observed enhancement in the color center's spontaneous emission rate, emission directionality, and cooperativity over a broad optical frequency range. Additionally, we studied the effect of plasmonic environments on the spin-readout sensitivity of color centers. The use of CMOS-compatible epitaxially grown plasmonic materials in the design of these nanophotonic structures promises a new level of performance for a variety of integrated room-temperature quantum devices based on diamond color centers.

  19. Third order nonlinear optical properties of a paratellurite single crystal

    Science.gov (United States)

    Duclère, J.-R.; Hayakawa, T.; Roginskii, E. M.; Smirnov, M. B.; Mirgorodsky, A.; Couderc, V.; Masson, O.; Colas, M.; Noguera, O.; Rodriguez, V.; Thomas, P.

    2018-05-01

    The (a,b) plane angular dependence of the third-order nonlinear optical susceptibility, χ(3) , of a c-cut paratellurite (α-TeO2) single crystal was quantitatively evaluated here by the Z-scan technique, using a Ti:sapphire femtosecond laser operated at 800 nm. In particular, the mean value Re( ⟨χ(3)⟩a,b )(α-TeO2) of the optical tensor has been extracted from such experiments via a direct comparison with the data collected for a fused silica reference glass plate. A R e (⟨χ(3)⟩(a,b )(α-TeO2)):R e (χ(3))(SiO2 glass) ratio roughly equal to 49.1 is found, and our result compares thus very favourably with the unique experimental value (a ratio of ˜50) reported by Kim et al. [J. Am. Ceram. Soc. 76, 2486 (1993)] for a pure TeO2 glass. In addition, it is shown that the angular dependence of the phase modulation within the (a,b) plane can be fully understood in the light of the strong dextro-rotatory power known for TeO2 materials. Taking into account the optical activity, some analytical model serving to estimate the diagonal and non-diagonal components of the third order nonlinear susceptibility tensor has been thus developed. Finally, Re( χxxxx(3) ) and Re( χxxyy(3) ) values of 95.1 ×10-22 m 2/V2 and 42.0 ×10-22 m2/V2 , respectively, are then deduced for a paratellurite single crystal, considering fused silica as a reference.

  20. Controlled elaboration of large-area plasmonic substrates by plasma process

    International Nuclear Information System (INIS)

    Pugliara, A; Despax, B; Makasheva, K; Bonafos, C; Carles, R

    2015-01-01

    Elaboration in a controlled way of large-area and efficient plasmonic substrates is achieved by combining sputtering of silver nanoparticles (AgNPs) and plasma polymerization of the embedding dielectric matrix in an axially asymmetric, capacitively coupled RF discharge maintained at low gas pressure. The plasma parameters and deposition conditions were optimized according to the optical response of these substrates. Structural and optical characterizations of the samples confirm the process efficiency. The obtained results indicate that to deposit a single layer of large and closely situated AgNPs, a high injected power and short sputtering times must be privileged. The plasma-elaborated plasmonic substrates appear to be very sensitive to any stimuli that affect their plasmonic response. (paper)

  1. Cost-Effective Brillouin Optical Time-Domain Analysis Sensor Using a Single Optical Source and Passive Optical Filtering

    Directory of Open Access Journals (Sweden)

    H. Iribas

    2016-01-01

    Full Text Available We present a simplified configuration for distributed Brillouin optical time-domain analysis sensors that aims to reduce the cost of the sensor by reducing the number of components required for the generation of the two optical waves involved in the sensing process. The technique is based on obtaining the pump and probe waves by passive optical filtering of the spectral components generated in a single optical source that is driven by a pulsed RF signal. The optical source is a compact laser with integrated electroabsorption modulator and the optical filters are based on fiber Bragg gratings. Proof-of-concept experiments demonstrate 1 m spatial resolution over a 20 km sensing fiber with a 0.9 MHz precision in the measurement of the Brillouin frequency shift, a performance similar to that of much more complex setups. Furthermore, we discuss the factors limiting the sensor performance, which are basically related to residual spectral components in the filtering process.

  2. Nanoscale devices based on plasmonic coaxial waveguide resonators

    Science.gov (United States)

    Mahigir, A.; Dastmalchi, P.; Shin, W.; Fan, S.; Veronis, G.

    2015-02-01

    Waveguide-resonator systems are particularly useful for the development of several integrated photonic devices, such as tunable filters, optical switches, channel drop filters, reflectors, and impedance matching elements. In this paper, we introduce nanoscale devices based on plasmonic coaxial waveguide resonators. In particular, we investigate threedimensional nanostructures consisting of plasmonic coaxial stub resonators side-coupled to a plasmonic coaxial waveguide. We use coaxial waveguides with square cross sections, which can be fabricated using lithography-based techniques. The waveguides are placed on top of a silicon substrate, and the space between inner and outer coaxial metals is filled with silica. We use silver as the metal. We investigate structures consisting of a single plasmonic coaxial resonator, which is terminated either in a short or an open circuit, side-coupled to a coaxial waveguide. We show that the incident waveguide mode is almost completely reflected on resonance, while far from the resonance the waveguide mode is almost completely transmitted. We also show that the properties of the waveguide systems can be accurately described using a single-mode scattering matrix theory. The transmission and reflection coefficients at waveguide junctions are either calculated using the concept of the characteristic impedance or are directly numerically extracted using full-wave three-dimensional finite-difference frequency-domain simulations.

  3. Accurate optical vector network analyzer based on optical single-sideband modulation and balanced photodetection.

    Science.gov (United States)

    Xue, Min; Pan, Shilong; Zhao, Yongjiu

    2015-02-15

    A novel optical vector network analyzer (OVNA) based on optical single-sideband (OSSB) modulation and balanced photodetection is proposed and experimentally demonstrated, which can eliminate the measurement error induced by the high-order sidebands in the OSSB signal. According to the analytical model of the conventional OSSB-based OVNA, if the optical carrier in the OSSB signal is fully suppressed, the measurement result is exactly the high-order-sideband-induced measurement error. By splitting the OSSB signal after the optical device-under-test (ODUT) into two paths, removing the optical carrier in one path, and then detecting the two signals in the two paths using a balanced photodetector (BPD), high-order-sideband-induced measurement error can be ideally eliminated. As a result, accurate responses of the ODUT can be achieved without complex post-signal processing. A proof-of-concept experiment is carried out. The magnitude and phase responses of a fiber Bragg grating (FBG) measured by the proposed OVNA with different modulation indices are superimposed, showing that the high-order-sideband-induced measurement error is effectively removed.

  4. Novel plasmonic polarimeter for biomedical imaging applications

    Science.gov (United States)

    Cheney, Alec; Chen, Borui; Cartwright, Alexander; Thomay, Tim

    2018-02-01

    Using polarized light in medical imaging is a valuable tool for diagnostic purposes since light traveling through scattering tissues such as skin, blood, or cartilage may be subject to changes in polarization. We present a new detection scheme and sensor that allows for directly measuring the polarization of light electronically using a plasmonic sensor. The sensor we fabricated consists of a plasmonic nano-grating that is embedded in a Wheatstone circuit. Using resistive losses induced by optically excited plasmons has shown promise as a CMOScompatible plasmonic light detector. Since the plasmonic response is sensitive to polarization with respect to the grating orientation, measuring the resistance change under incident light supplies a direct electronic measure of the polarization of light without polarization optics. Increased electron scattering introduced by plasmons in an applied current results in a measurable decrease in electrical conductance of a grating, allowing a purely electronic readout of a plasmonic excitation. Accordingly, because of its plasmonic nature, such a detector is dependent on both the wavelength and polarization of incident light with a response time limited by the surface plasmon lifetime.

  5. Plasmonic sensing

    DEFF Research Database (Denmark)

    Mogensen, Klaus Bo

    2015-01-01

    Plasmonic sensors typically rely on detection of changes in the refractive index of the surrounding medium. Here, an alternative approach is reported based on electrical surface screening and controlled dissolution of ultrasmall silver nanoparticles (NPs; R ... in the plasmon band. This is demonstrated by using the strong nucleophiles, cyanide and cysteamine, as ligands. The “dissolution paths” in terms of peak wavelength and amplitude shifts differ significantly between different types of analytes, which are suggested as a means to obtain selectivity of the detection...... that cannot be obtained by traditional refractive index sensing, without the use of bioprobes. A simple modified Drude model is used to account for shifts in the plasmon band position due to electrical charging. Here, a screening parameter is introduced in the expression for the free electron density...

  6. Plasmon hybridization in complex metallic nanostructures

    Science.gov (United States)

    Hao, Feng

    With Plasmon Hybridization (PH) and Finite-Difference Time-Domain (FDTD) method, we theoretically investigated the optical properties of some complex metallic nanostructures (coupled nanoparticle/wire, nanostars, nanorings and combined ring/disk nanocavity systems). We applied the analytical formulism of PH studying the plasmonic coupling of a spherical metallic nanoparticle and an infinite long cylindrical nanowire. The plasmon resonance of the coupled system is shown shifted in frequency, which highly depends on the polarization of incident light relative to the geometry of the structure. We also showed the nanoparticle serves as an efficient antenna coupling the electromagnetic radiation into the low-energy propagating wire plasmons. We performed an experimental and theoretical analysis of the optical properties of gold nanorings with different sizes and cross sections. For light polarized parallel to the ring, the optical spectrum sensitively depends on the incident angle. When light incidence is normal to the ring, two dipolar resonance is observed. As the incident light is titled, some previously dark mulipolar plasmon resonances will be excited as a consequence of the retardation. The concept of plasmon hybridization is combined with the power of brute-force numerical methods to understand the plasmonic properties of some very complicated nanostructures. We showed the plasmons of a gold nanostar are a result of hybridization of the plasmons of the core and the tips of the particle. The core serves as a nanoantenna, dramatically enhanced the optical spectrum and the field enhancement of the nanostar. We also applied this method analyzing the plasmonic modes of a nanocavity structure composed of a nanodisk with a surrounding minoring. For the concentric combination, we showed the nature of the plasmon modes can be understood as the plasmon hybrization of an individual ring and disk. The interation results in a blueshifted and broadened superradiant antibonding

  7. Photoacoustic measurements of photokinetics in single optically trapped aerosol droplets

    Science.gov (United States)

    Covert, Paul; Cremer, Johannes; Signorell, Ruth; Thaler, Klemens; Haisch, Christoph

    2017-04-01

    It is well established that interaction of light with atmospheric aerosols has a large impact on the Earth's climate. However, uncertainties in the magnitude of this impact remain large, due in part to broad distributions of aerosol size, composition, and chemical reactivity. In this context, photoacoustic spectroscopy is commonly used to measure light absorption by aerosols. Here, we present photoacoustic measurements of single, optically-trapped nanodroplets to reveal droplet size-depencies of photochemical and physical processes. Theoretical considerations have pointed to a size-dependence in the magnitude and phase of the photoacoustic response from aerosol droplets. This dependence is thought to originate from heat transfer processes that are slow compared to the acoustic excitation frequency. In the case of a model aerosol, our measurements of single particle absorption cross-section versus droplet size confirm these theoretical predictions. In a related study, using the same model aerosol, we also demonstrate a droplet size-dependence of photochemical reaction rates [1]. Within sub-micron sized particles, photolysis rates were observed to be an order of magnitude greater than those observed in larger droplets. [1] J. W. Cremer, K. M. Thaler, C. Haisch, and R. Signorell. Photoacoustics of single laser-trapped nanodroplets for the direct observation of nanofocusing in aerosol photokinetics. Nat. Commun., 7:10941, 2016.

  8. Chiral multichromic single crystals for optical devices (LDRD 99406).

    Energy Technology Data Exchange (ETDEWEB)

    Kemp, Richard Alan; Felix, Ana M. (University of New Mexico, Albuquerque, NM)

    2006-12-01

    This report summarizes our findings during the study of a novel system that yields multi-colored materials as products. This system is quite unusual as it leads to multi-chromic behavior in single crystals, where one would expect that only a single color would exist. We have speculated that these novel solids might play a role in materials applications such as non-linear optics, liquid crystal displays, piezoelectric devices, and other similar applications. The system examined consisted of a main-group alkyl compound (a p block element such as gallium or aluminum) complexed with various organic di-imines. The di-imines had substituents of two types--either alkyl or aromatic groups attached to the nitrogen atoms. We observed that single crystals, characterized by X-ray crystallography, were obtained in most cases. Our research during January-July, 2006, was geared towards understanding the factors leading to the multi-chromic nature of the complexes. The main possibilities put forth initially considered (a) the chiral nature of the main group metal, (b) possible reduction of the metal to a lower-valent, radical state, (c) the nature of the ligand(s) attached to the main group metal, and (d) possible degradation products of the ligand leading to highly-colored products. The work carried out indicates that the most likely explanation considered involves degradation of the aromatic ligands (a combination of (c) and (d)), as the experiments performed can clearly rule out (a) and (b).

  9. Advanced optical measurements for characterizing photophysical properties of single nanoparticles.

    Energy Technology Data Exchange (ETDEWEB)

    Polsky, Ronen; Davis, Ryan W.; Arango, Dulce C.; Brozik, Susan Marie; Wheeler, David Roger

    2009-09-01

    Formation of complex nanomaterials would ideally involve single-pot reaction conditions with one reactive site per nanoparticle, resulting in a high yield of incrementally modified or oriented structures. Many studies in nanoparticle functionalization have sought to generate highly uniform nanoparticles with tailorable surface chemistry necessary to produce such conjugates, with limited success. In order to overcome these limitations, we have modified commercially available nanoparticles with multiple potential reaction sites for conjugation with single ssDNAs, proteins, and small unilamellar vesicles. These approaches combined heterobifunctional and biochemical template chemistries with single molecule optical methods for improved control of nanomaterial functionalization. Several interesting analytical results have been achieved by leveraging techniques unique to SNL, and provide multiple paths for future improvements for multiplex nanoparticle synthesis and characterization. Hyperspectral imaging has proven especially useful for assaying substrate immobilized fluorescent particles. In dynamic environments, temporal correlation spectroscopies have been employed for tracking changes in diffusion/hydrodynamic radii, particle size distributions, and identifying mobile versus immobile sample fractions at unbounded dilution. Finally, Raman fingerprinting of biological conjugates has been enabled by resonant signal enhancement provided by intimate interactions with nanoparticles and composite nanoshells.

  10. An in-situ real-time optical fiber sensor based on surface plasmon resonance for monitoring the growth of TiO2 thin films.

    Science.gov (United States)

    Tsao, Yu-Chia; Tsai, Woo-Hu; Shih, Wen-Ching; Wu, Mu-Shiang

    2013-07-23

    An optical fiber sensor based on surface plasmon resonance (SPR) is proposed for monitoring the thickness of deposited nano-thin films. A side-polished multimode SPR optical fiber sensor with an 850 nm-LD is used as the transducing element for real-time monitoring of the deposited TiO2 thin films. The SPR optical fiber sensor was installed in the TiO2 sputtering system in order to measure the thickness of the deposited sample during TiO2 deposition. The SPR response declined in real-time in relation to the growth of the thickness of the TiO2 thin film. Our results show the same trend of the SPR response in real-time and in spectra taken before and after deposition. The SPR transmitted intensity changes by approximately 18.76% corresponding to 50 nm of deposited TiO2 thin film. We have shown that optical fiber sensors utilizing SPR have the potential for real-time monitoring of the SPR technology of nanometer film thickness. The compact size of the SPR fiber sensor enables it to be positioned inside the deposition chamber, and it could thus measure the film thickness directly in real-time. This technology also has potential application for monitoring the deposition of other materials. Moreover, in-situ real-time SPR optical fiber sensor technology is in inexpensive, disposable technique that has anti-interference properties, and the potential to enable on-line monitoring and monitoring of organic coatings.

  11. Hybrid dielectric waveguide spectroscopy of individual plasmonic nanoparticles

    Directory of Open Access Journals (Sweden)

    J. Cuadra

    2017-07-01

    Full Text Available Plasmonics is a mature scientific discipline which is now entering the realm of practical applications. Recently, significant attention has been devoted to on-chip hybrid devices where plasmonic nanoantennas are integrated in standard Si3N4 photonic waveguides. Light in these systems is usually coupled at the waveguide apexes by using multiple objectives and/or tapered optical fibers, rendering the analysis of spectroscopic signals a complicated task. Here, we show how by using a grating coupler and a low NA objective, quantitative spectroscopic information similar to standard dark-field spectroscopy can be obtained at the single-nanoparticle level. This technology may be useful for enabling single-nanoparticle studies in non-linear excitation regimes and/or in complex experimental environments, thus enriching the toolbox of nanophotonic methods.

  12. Excitation of multipolar surface plasmon resonance in plasmonic nanoparticles by complex accelerating beams

    Science.gov (United States)

    Yang, Yang; Li, Jiafang; Li, Zhi-Yuan; Chen, Yue-Gang

    2015-07-01

    In this paper, through a vector-spherical harmonics approach, we investigate the optical spectra of plasmonic Au nanoparticles excited by two special accelerating beams: a non-paraxial Airy beam and a Bessel beam. We systematically analyze the impacts of the beam profile, phase, and helical wave front of the electromagnetic fields on the optical spectrum and the excitation of the surface plasmon resonance (SPR). We find that the high-order phase in the Airy beam would result in strong plasmonic oscillations in the optical spectra, while the cone angle and orbital angular momentum carried by the Bessel beam could be employed to engineer the plasmon modes excited in Au nanoparticles. Furthermore, the optical spectrum excited by a combined Airy-Bessel-Gauss beam is discussed. The study could help to deeply explore new ways to manipulate SPR in metal nanoparticles via the wave front engineering of optical beams for enhancing light-matter interaction and optical sensing performance.

  13. Excitation of multipolar surface plasmon resonance in plasmonic nanoparticles by complex accelerating beams

    International Nuclear Information System (INIS)

    Yang, Yang; Li, Jiafang; Li, Zhi-Yuan; Chen, Yue-Gang

    2015-01-01

    In this paper, through a vector-spherical harmonics approach, we investigate the optical spectra of plasmonic Au nanoparticles excited by two special accelerating beams: a non-paraxial Airy beam and a Bessel beam. We systematically analyze the impacts of the beam profile, phase, and helical wave front of the electromagnetic fields on the optical spectrum and the excitation of the surface plasmon resonance (SPR). We find that the high-order phase in the Airy beam would result in strong plasmonic oscillations in the optical spectra, while the cone angle and orbital angular momentum carried by the Bessel beam could be employed to engineer the plasmon modes excited in Au nanoparticles. Furthermore, the optical spectrum excited by a combined Airy–Bessel–Gauss beam is discussed. The study could help to deeply explore new ways to manipulate SPR in metal nanoparticles via the wave front engineering of optical beams for enhancing light–matter interaction and optical sensing performance. (paper)

  14. Surface Plasmon Singularities

    Directory of Open Access Journals (Sweden)

    Gabriel Martínez-Niconoff

    2012-01-01

    Full Text Available With the purpose to compare the physical features of the electromagnetic field, we describe the synthesis of optical singularities propagating in the free space and on a metal surface. In both cases the electromagnetic field has a slit-shaped curve as a boundary condition, and the singularities correspond to a shock wave that is a consequence of the curvature of the slit curve. As prototypes, we generate singularities that correspond to fold and cusped regions. We show that singularities in free space may generate bifurcation effects while plasmon fields do not generate these kinds of effects. Experimental results for free-space propagation are presented and for surface plasmon fields, computer simulations are shown.

  15. Surface-Plasmon-Driven Hot Electron Photochemistry.

    Science.gov (United States)

    Zhang, Yuchao; He, Shuai; Guo, Wenxiao; Hu, Yue; Huang, Jiawei; Mulcahy, Justin R; Wei, Wei David

    2017-11-30

    Visible-light-driven photochemistry has continued to attract heightened interest due to its capacity to efficiently harvest solar energy and its potential to solve the global energy crisis. Plasmonic nanostructures boast broadly tunable optical properties coupled with catalytically active surfaces that offer a unique opportunity for solar photochemistry. Resonant optical excitation of surface plasmons produces energetic hot electrons that can be collected to facilitate chemical reactions. This review sums up recent theoretical and experimental approaches for understanding the underlying photophysical processes in hot electron generation and discusses various electron-transfer models on both plasmonic metal nanostructures and plasmonic metal/semiconductor heterostructures. Following that are highlights of recent examples of plasmon-driven hot electron photochemical reactions within the context of both cases. The review concludes with a discussion about the remaining challenges in the field and future opportunities for addressing the low reaction efficiencies in hot-electron-induced photochemistry.

  16. Current measurements by Faraday rotation in single mode optical fibers

    International Nuclear Information System (INIS)

    Chandler, G.I.; Jahoda, F.C.

    1984-01-01

    Development of techniques for measuring magnetic fields and currents by Faraday rotation in single-mode optical fibers has continued. We summarize the results of attempts to measure the toroidal plasma current in the ZT-40 Reversed-Field-Pinch using multi-turn fiber coils. The fiber response is reproducible and in accord with theory, but the amount and distribution of the stress-induced birefringence in this case are such that prediction of the sensor response at low currents is difficult if not impossible. The low-current difficulty can be overcome by twisting the fiber to induce a circular birefringence bias. We report the results of auxiliary experiments with a fiber that has been twisted with 15 turns per meter and then re-coated to lock the twist in place

  17. Optical absorption in gel grown cadmium tartrate single crystals

    International Nuclear Information System (INIS)

    Arora, S K; Kothari, A J; Patel, R G; Chauha, K M; Chudasama, B N

    2006-01-01

    Single crystals of cadmium tartrate pentahydrate (CTP) have been grown by the famous gel technique. The slow and controlled reaction between Cd 2+ and (C 4 H 4 O 6 ) 2- ions in silica hydrogel results in formation of the insoluble product, CdC 4 H 4 O 6 .5H 2 O. Optical absorption spectra have been recorded in the range 200 to 2500 nm. Fundamental absorption edge for electronic transition has been analyzed. The direct allowed transition is found to be present in the region of relatively higher photon energy. Analysis of the segments of α 1/2 versus hν graph has been made to separate individual contribution of phonons. The phonons involved in the indirect transition are found to correspond to 335 and 420 cm -1 . Scattering of charge carriers in the lattice is found due to acoustic phonons

  18. Perturbation theory for plasmonic modulation and sensing

    KAUST Repository

    Raman, Aaswath; Fan, Shanhui

    2011-01-01

    related to plasma frequency modulation in such systems. Our approach provides new physical insight for the design of plasmonic devices for biochemical sensing and optical modulation and future active metamaterial applications. © 2011 American Physical

  19. Localization Spectroscopy of a Single Ion in an Optical Lattice

    DEFF Research Database (Denmark)

    Legrand, Olivier Philippe Alexandre

    2015-01-01

    The work reported in this thesis primarily focuses on studies of the dynamics of a single laser-cooled ion, simultaneously confined in the harmonic potential of a linear Paul trap and a rapidly varying periodic potential – a so-called optical lattice – generated from an optical standing-wave. Bes...... as a new tool for future cavity quantum electrodynamics experiments in the Ion trap group at Aarhus University.......-wave. Besides providing a better understanding of the dynamics of an ion subjected to varying trapping conditions, this work establishes a basis for future studies of various quantum many-body physics models, for manipulations of the structure of large ion Coulomb crystals, and for optimization...... of the interaction between light and matter in connection with quantum information experiments. In addition to the deep, three-dimensional harmonic potential of the linear Paul trap which confines the ion in regions of several millimeters, one of the directions of the ion motion is constrained by the application...

  20. Optical Characterization and Applications of Single Walled Carbon Nanotubes

    Science.gov (United States)

    Strano, Michael S.

    2005-03-01

    Recent advances in the dispersion and separation of single walled carbon nanotubes have led to new methods of optical characterization and some novel applications. We find that Raman spectroscopy can be used to probe the aggregation state of single-walled carbon nanotubes in solution or as solids with a range of varying morphologies. Carbon nanotubes experience an orthogonal electronic dispersion when in electrical contact that broadens (from 40 meV to roughly 80 meV) and shifts the interband transition to lower energy (by 60 meV). We show that the magnitude of this shift is dependent on the extent of bundle organization and the inter-nanotube contact area. In the Raman spectrum, aggregation shifts the effective excitation profile and causes peaks to increase or decrease, depending on where the transition lies, relative to the excitation wavelength. The findings are particularly relevant for evaluating nanotube separation processes, where relative peak changes in the Raman spectrum can be confused for selective enrichment. We have also used gel electrophoresis and column chromatography conducted on individually dispersed, ultrasonicated single-walled carbon nanotubes to yield simultaneous separation by tube length and diameter. Electroelution after electrophoresis is shown to produce highly resolved fractions of nanotubes with average lengths between 92 and 435 nm. Separation by diameter is concomitant with length fractionation, and nanotubes that have been cut shortest also possess the greatest relative enrichments of large-diameter species. The relative quantum yield decreases nonlinearly as the nanotube length becomes shorter. These findings enable new applications of nanotubes as sensors and biomarkers. Particularly, molecular detection using near infrared (n-IR) light between 0.9 and 1.3 eV has important biomedical applications because of greater tissue penetration and reduced auto-fluorescent background in thick tissue or whole blood media. Carbon nanotubes

  1. Plasmons in Dimensionally Mismatched Coulomb Coupled Graphene Systems.

    Science.gov (United States)

    Badalyan, S M; Shylau, A A; Jauho, A P

    2017-09-22

    We calculate the plasmon dispersion relation for Coulomb coupled metallic armchair graphene nanoribbons and doped monolayer graphene. The crossing of the plasmon curves, which occurs for uncoupled 1D and 2D systems, is split by the interlayer Coulomb coupling into a lower and an upper plasmon branch. The upper branch exhibits an unusual behavior with end points at finite q. Accordingly, the structure factor shows either a single or a double peak behavior, depending on the plasmon wavelength. The new plasmon structure is relevant to recent experiments, its properties can be controlled by varying the system parameters and be used in plasmonic applications.

  2. Plasmon polaritons in nanostructured graphene

    DEFF Research Database (Denmark)

    Xiao, Sanshui

    2013-01-01

    Graphene has attracted considerable attention due to its unique electronic and optical properties. When graphene is electrically/chemically doped, it can support surface plasmon where the light propagates along the surface with a very short wavelength and an extremely small mode volume. The optical...... properties of graphene can be tuned by electrical gating, thus proving a promising way to realize a tunable plasmonic material. We firstly investigate the performance of bends and splitters in graphene nanoribbon waveguides, and show that bends and splitters do not induce any additional loss provided...... that the nanoribbon width is sub-wavelength. Then we experimentally demonstrate the excitation of graphene plasmon polaritons in a continuous graphene monolayer resting on a two-dimensional subwavelength silicon grating. The silicon grating is realized by a nanosphere lithography technique with a self...

  3. Terahertz plasmon and surface-plasmon modes in cylindrical metallic nanowires

    International Nuclear Information System (INIS)

    Wu Ping; Xu Wen; Li Long-Long; Lu Tie-Cheng; Wu Wei-Dong

    2014-01-01

    We present a theoretical study on collective excitation modes associated with plasmon and surface-plasmon oscillations in cylindrical metallic nanowires. Based on a two-subband model, the dynamical dielectric function matrix is derived under the random-phase approximation. An optic-like branch and an acoustic-like branch, which are free of Landau damping, are observed for both plasmon and surface-plasmon modes. Interestingly, for surface-plasmon modes, we find that two branches of the dispersion relation curves converge at a wavevector q z = q max beyond which no surface-plasmon mode exists. Moreover, we examine the dependence of these excitation modes on sample parameters such as the radius of the nanowires. It is found that in metallic nanowires realized by state-of-the-art nanotechnology the intra- and inter-subband plasmon and surface-plasmon frequencies are in the terahertz bandwidth. The frequency of the optic-like modes decreases with increasing radius of the nanowires, whereas that of the acoustic-like modes is not sensitive to the variation of the radius. This study is pertinent to the application of metallic nanowires as frequency-tunable terahertz plasmonic devices. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  4. Experimental and numerical optical characterization of plasmonic copper nanoparticles embedded in ZnO fabricated by ion implantation and annealing

    Energy Technology Data Exchange (ETDEWEB)

    Le, Khai Q. [Faculty of Science and Technology, Hoa Sen University, Ho Chi Minh City (Viet Nam); Department of Physics, Faculty of Science, Jazan University, P.O. Box 114, 45142 Jazan (Saudi Arabia); Nguyen, Hieu P.T. [Department of Electrical and Computer Engineering, New Jersey Institute of Technology, NJ 07102 (United States); Ngo, Quang Minh [Institute of Material Sciences, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay, Hanoi (Viet Nam); Canimoglu, Adil [Nigde University, Faculty of Arts and Sciences, Physics Department, Nigde (Turkey); Can, Nurdogan, E-mail: cannurdogan@yahoo.com [Celal Bayar University, Faculty of Arts and Sciences, Department of Physics, Muradiye, Manisa (Turkey); Department of Physics, Faculty of Science, Jazan University, P.O. Box 114, 45142 Jazan (Saudi Arabia)

    2016-06-05

    Here we describe the successfully fabrication of metal nanoparticle crystals by implanting copper (Cu) ions into single zinc oxide (ZnO) crystals with ion energy of 400 keV at ion doses of 1 × 10{sup 16} to 1 × 10{sup 17} ions/cm{sup 2}. After implantation and post-annealing treatment, the Cu implanted ZnO produces a broad range of luminescence emissions, ranging from green to yellow. A green luminescence peak at 550 nm could be ascribed to the isolated Cu ions. The changes in luminescence emission bands between the initial implant and annealed suggest that the implants give rise to clustering Cu nanoparticles in the host matrix but that the annealing process dissociates these. Numerical modelling of the Cu nanoparticles was employed to simulate their optical properties including the extinction cross section, electron energy loss spectroscopy and cathodoluminescence. We demonstrate that the clustering of nanoparticles generates Fano resonances corresponding to the generation of multiple resonances, while the isolation of nanoparticles results in intensity amplification. - Highlights: • We present the fabrication of metal nanoparticle crystals by implanting Cu into ZnO. • The luminescence properties were studied at different annealing temperature. • Numerical modelling of the Cu nanoparticles was employed. • We demonstrate that the clustering of nanoparticles generates Fano resonances.

  5. A comprehensive strategy for the analysis of acoustic compressibility and optical deformability on single cells

    DEFF Research Database (Denmark)

    Yang, Tie; Bragheri, Francesca; Nava, Giovanni

    2016-01-01

    We realized an integrated microfluidic chip that allows measuring both optical deformability and acoustic compressibility on single cells, by optical stretching and acoustophoresis experiments respectively. Additionally, we propose a measurement protocol that allows evaluating the experimental ap...

  6. Ultra-Low Power Optical Transistor Using a Single Quantum Dot Embedded in a Photonic Wire

    DEFF Research Database (Denmark)

    Nguyen, H.A.; Grange, T.; Malik, N.S.

    2017-01-01

    Using a single InAs quantum dot embedded in a GaAs photonic wire, we realize a giant non-linearity between two optical modes to experimentally demonstrate an all-optical transistor triggered by 10 photons.......Using a single InAs quantum dot embedded in a GaAs photonic wire, we realize a giant non-linearity between two optical modes to experimentally demonstrate an all-optical transistor triggered by 10 photons....

  7. Optical and Electrical Performance of MOS-Structure Silicon Solar Cells with Antireflective Transparent ITO and Plasmonic Indium Nanoparticles under Applied Bias Voltage.

    Science.gov (United States)

    Ho, Wen-Jeng; Sue, Ruei-Siang; Lin, Jian-Cheng; Syu, Hong-Jang; Lin, Ching-Fuh

    2016-08-10

    This paper reports impressive improvements in the optical and electrical performance of metal-oxide-semiconductor (MOS)-structure silicon solar cells through the incorporation of plasmonic indium nanoparticles (In-NPs) and an indium-tin-oxide (ITO) electrode with periodic holes (perforations) under applied bias voltage. Samples were prepared using a plain ITO electrode or perforated ITO electrode with and without In-NPs. The samples were characterized according to optical reflectance, dark current voltage, induced capacitance voltage, external quantum efficiency, and photovoltaic current voltage. Our results indicate that induced capacitance voltage and photovoltaic current voltage both depend on bias voltage, regardless of the type of ITO electrode. Under a bias voltage of 4.0 V, MOS cells with perforated ITO and plain ITO, respectively, presented conversion efficiencies of 17.53% and 15.80%. Under a bias voltage of 4.0 V, the inclusion of In-NPs increased the efficiency of cells with perforated ITO and plain ITO to 17.80% and 16.87%, respectively.

  8. Numerical studies on a plasmonic temperature nanosensor based on a metal-insulator-metal ring resonator structure for optical integrated circuit applications

    Science.gov (United States)

    Al-mahmod, Md. Jubayer; Hyder, Rakib; Islam, Md Zahurul

    2017-07-01

    A nanosensor, based on a metal-insulator-metal (MIM) plasmonic ring resonator, is proposed for potential on-chip temperature sensing and its performance is evaluated numerically. The sensor components can be fabricated by using planar processes on a silicon substrate, making its manufacturing compatible to planar electronic fabrication technology. The sensor, constructed using silver as the metal rings and a thermo-optic liquid ethanol film between the metal layers, is capable of sensing temperature with outstanding optical sensitivity, as high as -0.53 nm/°C. The resonance wavelength is found to be highly sensitive to the refractive index of the liquid dielectric film. The resonance peak can be tuned according to the requirement of intended application by changing the radii of the ring resonator geometries in the design phase. The compact size, planar and silicon-based design, and very high resolutions- these characteristics are expected to make this sensor technology a preferred choice for lab-on-a-chip applications, as compared to other contemporary sensors.

  9. Optical and Electrical Performance of MOS-Structure Silicon Solar Cells with Antireflective Transparent ITO and Plasmonic Indium Nanoparticles under Applied Bias Voltage

    Directory of Open Access Journals (Sweden)

    Wen-Jeng Ho

    2016-08-01

    Full Text Available This paper reports impressive improvements in the optical and electrical performance of metal-oxide-semiconductor (MOS-structure silicon solar cells through the incorporation of plasmonic indium nanoparticles (In-NPs and an indium-tin-oxide (ITO electrode with periodic holes (perforations under applied bias voltage. Samples were prepared using a plain ITO electrode or perforated ITO electrode with and without In-NPs. The samples were characterized according to optical reflectance, dark current voltage, induced capacitance voltage, external quantum efficiency, and photovoltaic current voltage. Our results indicate that induced capacitance voltage and photovoltaic current voltage both depend on bias voltage, regardless of the type of ITO electrode. Under a bias voltage of 4.0 V, MOS cells with perforated ITO and plain ITO, respectively, presented conversion efficiencies of 17.53% and 15.80%. Under a bias voltage of 4.0 V, the inclusion of In-NPs increased the efficiency of cells with perforated ITO and plain ITO to 17.80% and 16.87%, respectively.

  10. Influence of growth temperature on electrical, optical, and plasmonic properties of aluminum:zinc oxide films grown by radio frequency magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Dondapati, Hareesh; Santiago, Kevin; Pradhan, A. K. [Center for Materials Research, Norfolk State University, 700 Park Avenue, Norfolk, Virginia 23504 (United States)

    2013-10-14

    We have investigated the responsible mechanism for the observation of metallic conductivity at room temperature and metal-semiconductor transition (MST) at lower temperatures for aluminum-doped zinc oxide (AZO) films. AZO films were grown on glass substrates by radio-frequency magnetron sputtering with varying substrate temperatures (T{sub s}). The films were found to be crystalline with the electrical resistivity close to 1.1 × 10{sup −3} Ω cm and transmittance more than 85% in the visible region. The saturated optical band gap of 3.76 eV was observed for the sample grown at T{sub s} of 400 °C, however, a slight decrease in the bandgap was noticed above 400 °C, which can be explained by Burstein–Moss effect. Temperature dependent resistivity measurements of these highly conducting and transparent films showed a MST at ∼110 K. The observed metal-like and metal-semiconductor transitions are explained by taking into account the Mott phase transition and localization effects due to defects. All AZO films demonstrate crossover in permittivity from positive to negative and low loss in the near-infrared region, illustrating its applications for plasmonic metamaterials, including waveguides for near infrared telecommunication region. Based on the results presented in this study, the low electrical resistivity and high optical transmittance of AZO films suggested a possibility for the application in the flexible electronic devices, such as transparent conducting oxide film on LEDs, solar cells, and touch panels.

  11. The development of optical microscopy techniques for the advancement of single-particle studies

    Science.gov (United States)

    Marchuk, Kyle

    Single particle orientation and rotational tracking (SPORT) has recently become a powerful optical microscopy tool that can expose many molecular motions. Unfortunately, there is not yet a single microscopy technique that can decipher all particle motions in all environmental conditions, thus there are limitations to current technologies. Within, the two powerful microscopy tools of total internal reflection and interferometry are advanced to determine the position, orientation, and optical properties of metallic nanoparticles in a variety of environments. Total internal reflection is an optical phenomenon that has been applied to microscopy to produce either fluorescent or scattered light. The non-invasive far-field imaging technique is coupled with a near-field illumination scheme that allows for better axial resolution than confocal microscopy and epi-fluorescence microscopy. By controlling the incident illumination angle using total internal reflection fluorescence (TIRF) microscopy, a new type of imaging probe called "non-blinking" quantum dots (NBQDs) were super-localized in the axial direction to sub-10-nm precision. These particles were also used to study the rotational motion of microtubules being propelled by the motor protein kinesin across the substrate surface. The same instrument was modified to function under total internal reflection scattering (TIRS) microscopy to study metallic anisotropic nanoparticles and their dynamic interactions with synthetic lipid bilayers. Utilizing two illumination lasers with opposite polarization directions at wavelengths corresponding to the short and long axis surface plasmon resonance (SPR) of the nanoparticles, both the in-plane and out-of-plane movements of many particles could be tracked simultaneously. When combined with Gaussian point spread function (PSF) fitting for particle super-localization, the binding status and rotational movement could be resolved without degeneracy. TIRS microscopy was also used to

  12. The development of optical microscopy techniques for the advancement of single-particle studies

    Energy Technology Data Exchange (ETDEWEB)

    Marchuk, Kyle [Iowa State Univ., Ames, IA (United States)

    2013-05-15

    Single particle orientation and rotational tracking (SPORT) has recently become a powerful optical microscopy tool that can expose many molecular motions. Unfortunately, there is not yet a single microscopy technique that can decipher all particle motions in all environmental conditions, thus there are limitations to current technologies. Within, the two powerful microscopy tools of total internal reflection and interferometry are advanced to determine the position, orientation, and optical properties of metallic nanoparticles in a variety of environments. Total internal reflection is an optical phenomenon that has been applied to microscopy to produce either fluorescent or scattered light. The non-invasive far-field imaging technique is coupled with a near-field illumination scheme that allows for better axial resolution than confocal microscopy and epi-fluorescence microscopy. By controlling the incident illumination angle using total internal reflection fluorescence (TIRF) microscopy, a new type of imaging probe called “non-blinking” quantum dots (NBQDs) were super-localized in the axial direction to sub-10-nm precision. These particles were also used to study the rotational motion of microtubules being propelled by the motor protein kinesin across the substrate surface. The same instrument was modified to function under total internal reflection scattering (TIRS) microscopy to study metallic anisotropic nanoparticles and their dynamic interactions with synthetic lipid bilayers. Utilizing two illumination lasers with opposite polarization directions at wavelengths corresponding to the short and long axis surface plasmon resonance (SPR) of the nanoparticles, both the in-plane and out-of-plane movements of many particles could be tracked simultaneously. When combined with Gaussian point spread function (PSF) fitting for particle super-localization, the binding status and rotational movement could be resolved without degeneracy. TIRS microscopy was also used to

  13. 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...

  14. Developing new optical imaging techniques for single particle and molecule tracking in live cells

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Wei [Iowa State Univ., Ames, IA (United States)

    2010-01-01

    Differential interference contrast (DIC) microscopy is a far-field as well as wide-field optical imaging technique. Since it is non-invasive and requires no sample staining, DIC microscopy is suitable for tracking the motion of target molecules in live cells without interfering their functions. In addition, high numerical aperture objectives and condensers can be used in DIC microscopy. The depth of focus of DIC is shallow, which gives DIC much better optical sectioning ability than those of phase contrast and dark field microscopies. In this work, DIC was utilized to study dynamic biological processes including endocytosis and intracellular transport in live cells. The suitability of DIC microscopy for single particle tracking in live cells was first demonstrated by using DIC to monitor the entire endocytosis process of one mesoporous silica nanoparticle (MSN) into a live mammalian cell. By taking advantage of the optical sectioning ability of DIC, we recorded the depth profile of the MSN during the endocytosis process. The shape change around the nanoparticle due to the formation of a vesicle was also captured. DIC microscopy was further modified that the sample can be illuminated and imaged at two wavelengths simultaneously. By using the new technique, noble metal nanoparticles with different shapes and sizes were selectively imaged. Among all the examined metal nanoparticles, gold nanoparticles in rod shapes were found to be especially useful. Due to their anisotropic optical properties, gold nanorods showed as diffraction-limited spots with disproportionate bright and dark parts that are strongly dependent on their orientation in the 3D space. Gold nanorods were developed as orientation nanoprobes and were successfully used to report the self-rotation of gliding microtubules on kinesin coated substrates. Gold nanorods were further used to study the rotational motions of cargoes during the endocytosis and intracellular transport processes in live mammalian

  15. Nano-Gap Embedded Plasmonic Gratings for Surface Plasmon Enhanced Fluorescence

    Science.gov (United States)

    Bhatnagar, Kunal; Bok, Sangho; Korampally, Venumadhav; Gangopadhyay, Shubhra

    2012-02-01

    Plasmonic nanostructures have been extensively used in the past few decades for applications in sub-wavelength optics, data storage, optoelectronic circuits, microscopy and bio-photonics. The enhanced electromagnetic field produced at the metal/dielectric interface by the excitation of surface plasmons via incident radiation can be used for signal enhancement in fluorescence and surface enhanced Raman scattering studies. Novel plasmonic structures on the sub wavelength scale have been shown to provide very efficient and extreme light concentration at the nano-scale. The enhanced electric field produced within a few hundred nanometers of these structures can be used to excite fluorophores in the surrounding environment. Fluorescence based bio-detection and bio-imaging are two of the most important tools in the life sciences. Improving the qualities and capabilities of fluorescence based detectors and imaging equipment has been a big challenge to the industry manufacturers. We report the novel fabrication of nano-gap embedded periodic grating substrates on the nanoscale using micro-contact printing and polymethylsilsesquioxane (PMSSQ) polymer. Fluorescence enhancement of up to 118 times was observed with these silver nanostructures in conjugation with Rhodamine-590 fluorescent dye. These substrates are ideal candidates for low-level fluorescence detection and single molecule imaging.

  16. 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.

  17. Enhanced and Tunable Optical Quantum Efficiencies from Plasmon Bandwidth Engineering in Bimetallic CoAg Nanoparticles (Open Access Publisher’s Version)

    Science.gov (United States)

    2016-08-01

    size for the Co-Ag systems . in Fig. 2(b). Fig. 2(c) compares the plasmon resonance energy and the bandwidth of the bimetallic systems as a function...nanoparticle shape and size effects on aluminum oxide-induced enhancement of exciton-plasmon coupling and quantum dot emission J. Appl. Phys. 118, 124302...thin film photovoltaics : A case-study on organic devices J. Appl. Phys. 116, 114510 (2014); 10.1063/1.4896167 Cascaded plasmon resonant field

  18. Quantum emitters coupled to surface plasmons of an nanowire

    DEFF Research Database (Denmark)

    Dzsotjan, David; Sørensen, Anders Søndberg; Fleischhauer, Michael

    2010-01-01

    We investigate a system consisting of a single, as well as two emitters strongly coupled to surface plasmon modes of a nanowire using a Green's function approach. Explicit expressions are derived for the spontaneous decay rate into the plasmon modes and for the atom-plasmon coupling as well......-qubit quantum gate. We also discuss a possible realization of interesting many-body Hamiltonians, such as the spin-boson model, using strong emitter-plasmon coupling. Udgivelsesdato: 27 August...

  19. Manipulation of plasmonic wavefront and light–matter interaction in metallic nanostructures: A brief review

    International Nuclear Information System (INIS)

    Li Jia-Fang; Li Zhi-Yuan

    2014-01-01

    The control and application of surface plasmons (SPs), is introduced with particular emphasis on the manipulation of the plasmonic wavefront and light–matter interaction in metallic nanostructures. We introduce a direct design methodology called the surface wave holography method and show that it can be readily employed for wave-front shaping of near-infrared light through a subwavelength hole, it can also be used for designing holographic plasmonic lenses for SPs with complex wavefronts in the visible band. We also discuss several issues of light–matter interaction in plasmonic nanostructures. We show theoretically that amplification of SPs can be achieved in metal nanoparticles incorporated with gain media, leading to a giant reduction of surface plasmon resonance linewidth and enhancement of local electric field intensity. We present an all-analytical semiclassical theory to evaluate spaser performance in a plasmonic nanocavity incorporated with gain media described by the four-level atomic model. We experimentally demonstrate amplified spontaneous emission of SP polaritons and their amplification at the interface between a silver film and a polymer film doped with dye molecules. We discuss various aspects of microscopic and macroscopic manipulation of fluorescent radiation from gold nanorod hybrid structures in a system of either a single nanoparticle or an aligned group of nanoparticles. The findings reported and reviewed here could help others explore various approaches and schemes to manipulate plasmonic wavefront and light–matter interaction in metallic nanostructures for potential applications, such as optical displays, information integration, and energy harvesting technologies. (topical review - plasmonics and metamaterials)

  20. 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.