WorldWideScience

Sample records for copolymer planar waveguide

  1. Improved optical planar waveguides for lasers Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Demonstrate efficacy of a novel growth technique for planar waveguides (PWG) Enable PWG laser technology with improved performance, efficiency and manufacturability....

  2. Graded-index planar waveguide solar concentrator.

    Science.gov (United States)

    Bouchard, Sébastien; Thibault, Simon

    2014-03-01

    Planar waveguides are useful to transport, concentrate and distribute light uniformly over large dimensions. Their capacity to collect and gather light efficiently over a large distance is interesting for many applications, like backlighting and solar concentration. For these reasons, the possibility of making them even more efficient could be of considerable interest for the community. The observation of the ray path inside a graded-index (GRIN) fiber inspired the development of a similar technology inside planar waveguides. In this Letter, we show that it has the potential to dramatically increase the efficiency of planar waveguide-based solar concentrators or backlighting using GRIN planar waveguides.

  3. DWDM Devices Based on Planar Waveguide Technologies

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A review is presented on some of our recent results for designs, simulations and fabrication of several photonic integrated devices, such as arrayed-waveguide gratings (AWGs) and etched diffraction gratings (EDGs), based on planar waveguide technologies. Some novel designs for flat-top AWGs and EDGs with flat-top spectral responses are presented.

  4. Progress in planar optical waveguides

    CERN Document Server

    Wang, Xianping; Cao, Zhuangqi

    2016-01-01

    This book provides a comprehensive description of various slab waveguide structures ranged from graded-index waveguide to symmetrical metal-cladding waveguide. In this book, the transfer Matrix method is developed and applied to analyze the simplest case and the complex generalizations. A novel symmetrical metal-cladding waveguide structure is proposed and systematically investigated for several issues of interest, such as biochemical sensing, Goos-Hänchen shift and the slow light effect, etc. Besides, this book summarizes the authors’ research works on waveguides over the last decade. The readers who are familiar with basic optics theory may find this book easy to read and rather inspiring.

  5. Long-Period Gratings in Planar Optical Waveguides

    Institute of Scientific and Technical Information of China (English)

    Kin; Seng; Chiang

    2003-01-01

    Our progress in the study of long-period gratings (LPGs) in planar optical waveguides is reviewed. In particular, experimental LPGs in glass and polymer waveguides are presented to demonstrate the potential of LPG-based waveguide devices.

  6. Long-Period Gratings in Planar Optical Waveguides

    Institute of Scientific and Technical Information of China (English)

    Kin Seng Chiang

    2003-01-01

    Our progress in the study of long-period gratings (LPGs) in planar optical waveguides is reviewed. In particular,experimental LPGs in glass and polymer waveguides are presented to demonstrate the potential of LPG-based waveguide devices.

  7. Terahertz planar waveguide devices based on graphene

    Science.gov (United States)

    Yuan, Yizhe; Guo, Xiaoyong; An, Liqun; Xu, Wen

    2017-02-01

    We present a theoretical study on graphene-semiconductor planar structures. The frequency of the photonic modes in the structure, which can be efficiently tuned via varying the sample parameters, is within the terahertz (THz) bandwidth. Furthermore, it is found that a roughly linear dispersion relation can be obtained for photonic modes in the THz region. Hence, the proposed graphene-semiconductor planar structures can be served as THz waveguide with desirable transmission characteristics.

  8. PLANAR OPTICAL WAVEGUIDES WITH PHOTONIC CRYSTAL STRUCTURE

    DEFF Research Database (Denmark)

    2003-01-01

    Planar optical waveguide comprising a core region and a cladding region comprising a photonic crystal material, said photonic crystal material having a lattice of column elements, wherein at least a number of said column elements are elongated substantially in an axial direction for said core reg...

  9. Planar-waveguide integrated spectral comparator.

    Science.gov (United States)

    Mossberg, T W; Iazikov, D; Greiner, C

    2004-06-01

    A cost-effective yet robust and versatile dual-channel spectral comparator is presented. The silica-on-silicon planar-waveguide integrated device includes two holographic Bragg-grating reflectors (HBRs) with complementary spectral transfer functions. Output comprises projections of input signal spectra onto the complementary spectral channels. Spectral comparators may be useful in optical code-division multiplexing, optical packet decoding, spectral target recognition, and the identification of molecular spectra. HBRs may be considered to be mode-specific photonic crystals.

  10. Planar waveguide amplifiers and laser in erbium doped silica

    DEFF Research Database (Denmark)

    Guldberg-Kjær, Søren Andreas; Kristensen, Martin

    1999-01-01

    The objective of this work was to develop optically amplifying planar waveguides, using erbium-doped germano-silicate glass films deposited by PECVD (Plasma Enhanced Chemical Vapour Deposition). The waveguides should exhibit enough gain to be useful as optical amplifiers in integrated planar ligh...... as well as thermal influence. A simple method for producing an array of planar waveguide lasers is presented and it is shown that the difference in output wavelength of the individual lasers can be controlled with great accuracy.......The objective of this work was to develop optically amplifying planar waveguides, using erbium-doped germano-silicate glass films deposited by PECVD (Plasma Enhanced Chemical Vapour Deposition). The waveguides should exhibit enough gain to be useful as optical amplifiers in integrated planar...... fluorescence level. In addition the first measurement of the diffusion coefficient of erbim in silica is presented and it is shown that erbium rich precipitates are formed in areas of high erbium concentration. The manufacturing of planar waveguide structures using RIE (Reactive Ion Etching) is described...

  11. Planar photonic crystal waveguides in silicon oxynitride

    DEFF Research Database (Denmark)

    Liu, Haoling; Frandsen, Lars Hagedorn; Borel, Peter Ingo;

    Most work on planar photonic crystals has been performed on structures based on semiconducting crystals such as Si and III-V compounds. Due to the high index contrast between the host material and the air holes (e.g., Si has n = 3.5), these structures exhibit a large photonic band gap. However......ON glasses with different indices between 1.46 and 1.77 and we are currently fabricating photonic crystals in SiON on a silica buffer layer on Si. Simulations show that a complete band gap can indeed be created for TE-polarised light in the SiON structures, making them promising candidates for new photonic......, at visible wavelengths they absorb light very strongly. In contrary, silicon oxynitride (SiON) glasses offer high transparency down to blue and ultraviolet wavelengths. Thus, SiON photonic crystal waveguides can open for new possibilities, e.g., within sensing and life sciences. We have fabricated Si...

  12. Planar waveguide amplifiers and laser in erbium doped silica

    DEFF Research Database (Denmark)

    Guldberg-Kjær, Søren Andreas; Kristensen, Martin

    1999-01-01

    The objective of this work was to develop optically amplifying planar waveguides, using erbium-doped germano-silicate glass films deposited by PECVD (Plasma Enhanced Chemical Vapour Deposition). The waveguides should exhibit enough gain to be useful as optical amplifiers in integrated planar...... fluorescence level. In addition the first measurement of the diffusion coefficient of erbim in silica is presented and it is shown that erbium rich precipitates are formed in areas of high erbium concentration. The manufacturing of planar waveguide structures using RIE (Reactive Ion Etching) is described...... and it is shown that sidewall roughness resulting from micro masking by non-volatile reaction products can be minimised through a careful choice of etching parameters. This results in low propagation loss for the fabricated waveguides. It is shown that the achievable population inversion depends on the eribum...

  13. Optically amplifying planar glass waveguides: Laser on a chip

    DEFF Research Database (Denmark)

    Guldberg-Kjær, Søren Andreas

    with UV-light and that permanent Bragg-gratings can be induced. Planar waveguide lasers with integrated Bragg-gratings are manufactured and characterised. It is shown that linewidths below 125 kHz and output powers around 0.5 mW can be obtained, and that the manufactured lasers are resistant to mechanical......The objective of this work was to devlop optically amplifying planar wavguides, using erbium-doped germano-silicate glass films deposited by PECVD (Plasma Enhanced Chemical Vapour Deposition). The waveguides should exhibit enough gain to be useful as optical amplifiers in integrated planar...... lightwave circuits, as well as provide the gain medium for integrated planar waveguide lasers. The work and the obtained results are presented in this thesis: The manufacturing of silica thin films is described and it is shown that the refractive index of the films can be controlled by germanium co...

  14. Study of WDM polymer planar curved waveguide couplers

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A wavelength division multiplexer based on curved polymer planar waveguide is proposed. According to the coupled mode theory and the waveguide structure, the performance of the curved waveguide coupler (CWC) is analyzed. The results show that CWC can accommodate wider multiplexing bandwidth than parallel straight waveguide coupler (SWC) due to the compensation effect of the effective coupling length. The two variables, curvature radius and minimum spacing, increase the design flexibility of the waveguide device. A 4-channel wavelength division multiplexing (WDM) system based on CWC is designed. The deviation of the center wavelength, due to the errors of curvature radius and minimum spacing during fabrication process, is investigated. The smaller the curvature radius and the minimum spacing are, the larger the central wavelength deviation caused by the error of the curvature radius and the minimum spacing is, which provides some useful theoretical basis for the design and the fabrication of polymer waveguide devices.

  15. Ti:sapphire rib channel waveguide fabricated by reactive ion etching of a planar waveguide

    NARCIS (Netherlands)

    Crunteanu, A.; Jänchen, G.; Salathé, R.P.; Hoffmann, P.; Pollnau, M.; Eason, R.W.; Shepherd, D.P.

    2002-01-01

    We were successful in creating 1.4-µm high ribs in a Ti:sapphire planar waveguide by reactive ion etching. Optical investigations of the obtained structure showed channel-waveguide fluorescence emission of the Ti:sapphire layer after Ar-ion excitation.

  16. Large-bandwidth planar photonic crystal waveguides

    DEFF Research Database (Denmark)

    Søndergaard, Thomas; Lavrinenko, Andrei

    2002-01-01

    A general design principle is presented for making finite-height photonic crystal waveguides that support leakage-free guidance of light over large frequency intervals. The large bandwidth waveguides are designed by introducing line defects in photonic crystal slabs, where the material in the lin......-free single-mode guidance is found for a large frequency interval covering 60% of the photonic band-gap.......A general design principle is presented for making finite-height photonic crystal waveguides that support leakage-free guidance of light over large frequency intervals. The large bandwidth waveguides are designed by introducing line defects in photonic crystal slabs, where the material in the line...... defect has appropriate dispersion properties relative to the photonic crystal slab material surrounding the line defect. A three-dimensional theoretical analysis is given for large-bandwidth waveguide designs based on a silicon-air photonic crystal slab suspended in air. In one example, the leakage...

  17. Compact cladding-pumped planar waveguide amplifier and fabrication method

    Science.gov (United States)

    Bayramian, Andy J.; Beach, Raymond J.; Honea, Eric; Murray, James E.; Payne, Stephen A.

    2003-10-28

    A low-cost, high performance cladding-pumped planar waveguide amplifier and fabrication method, for deployment in metro and access networks. The waveguide amplifier has a compact monolithic slab architecture preferably formed by first sandwich bonding an erbium-doped core glass slab between two cladding glass slabs to form a multi-layer planar construction, and then slicing the construction into multiple unit constructions. Using lithographic techniques, a silver stripe is deposited and formed at a top or bottom surface of each unit construction and over a cross section of the bonds. By heating the unit construction in an oven and applying an electric field, the silver stripe is then ion diffused to increase the refractive indices of the core and cladding regions, with the diffusion region of the core forming a single mode waveguide, and the silver diffusion cladding region forming a second larger waveguide amenable to cladding pumping with broad area diodes.

  18. Optically amplifying planar glass waveguides: Laser on a chip

    DEFF Research Database (Denmark)

    Guldberg-Kjær, Søren Andreas

    The objective of this work was to devlop optically amplifying planar wavguides, using erbium-doped germano-silicate glass films deposited by PECVD (Plasma Enhanced Chemical Vapour Deposition). The waveguides should exhibit enough gain to be useful as optical amplifiers in integrated planar...... fluoresence level. In addition the first measurement of the diffusion coefficient of erbium in silica is presented and it is shown that eribum rich precipitaties are formed in areas of high erbium concentration. The manufacturing of planar waveguide structures using RIE (Reactive Ion Etching) is described...... and it is shown that sidewall roughness resulting from micro masking by non-volatile reaction products can be minimised through a carful choice of etching parameters. This results in low propagation loss for the fabricated waveguides. It is shown that the achivable population inversion depends on the erbium...

  19. Large-bandwidth planar photonic crystal waveguides

    DEFF Research Database (Denmark)

    Søndergaard, Thomas; Lavrinenko, Andrei

    2002-01-01

    A general design principle is presented for making finite-height photonic crystal waveguides that support leakage-free guidance of light over large frequency intervals. The large bandwidth waveguides are designed by introducing line defects in photonic crystal slabs, where the material in the line...... defect has appropriate dispersion properties relative to the photonic crystal slab material surrounding the line defect. A three-dimensional theoretical analysis is given for large-bandwidth waveguide designs based on a silicon-air photonic crystal slab suspended in air. In one example, the leakage...

  20. Planar waveguide laser in Er/Al-doped germanosilicate

    DEFF Research Database (Denmark)

    Guldberg-Kjær, Søren Andreas; Hübner, Jörg; Kristensen, Martin;

    1999-01-01

    A singlemode DBR laser is demonstrated in an Er/Al-doped germanosilicate planar waveguide. 0.4 mW of output power has been obtained at 1.553 mu m using internal Bragg reflectors produced by UV-induced index modulations.......A singlemode DBR laser is demonstrated in an Er/Al-doped germanosilicate planar waveguide. 0.4 mW of output power has been obtained at 1.553 mu m using internal Bragg reflectors produced by UV-induced index modulations....

  1. X-Ray Propagation in Tapered Planar Waveguide

    Science.gov (United States)

    Dolocan, Andrei; van der Veen, J. Friso

    The present paper focuses on the tapered planar waveguide solution for an initial given wave form. The algorithm is constructed in distributions space such that the calculations can be actually computed by taking some hypothesis regarding the mode series which appear. The whole argument leads to the conclusion that the wave is compressed towards the waveguide in the direction of tilting, leading thereafter to a focusing phenomena. We present two alternative constructions in order to compute the convolution which gives the wave inside the waveguide. The hypothesis are providing results in good approximation with the real evolution of the field within the definition domain.

  2. ytterbium- & erbium-doped silica for planar waveguide lasers & amplifiers

    DEFF Research Database (Denmark)

    Dyndgaard, Morten Glarborg

    2001-01-01

    fabricated using plasma enhanced chemical vapor deposition (PECVD) and reactive ion etching (RIE). These processes and the control of the film composition is discussed. Ytterbium doped planar waveguides are demonstrated, and it is shown that codoping with aluminium has a positive influence...

  3. Graphene Q-switched Yb:KYW planar waveguide laser

    NARCIS (Netherlands)

    Kim, Jun Wan; Choi, Sun Young; Aravazhi, Shanmugam; Pollnau, Markus; Griebner, Uwe; Petrov, Valentin; Bae, Sukang; Ahn, Kwang Jun; Yeom, Dong-Il; Rotermund, Fabian

    2015-01-01

    A diode-pumped Yb:KYW planar waveguide laser, single-mode Q-switched by evanescent-field interaction with graphene, is demonstrated for the first time. Few-layer graphene grown by chemical vapor deposition is transferred onto the top of a guiding layer, which initiates stable Q-switched operation in

  4. Planar Silicon Optical Waveguide Light Modulators

    DEFF Research Database (Denmark)

    Leistiko, Otto; Bak, H.

    1994-01-01

    serve as carrier injectors for controling absorption. Light confinement of single mode devices is good, giving spot sizes of 9 ¿m FWHM. Insertion loss measurements indicate that the absorption losses for these waveguides are extremely low, less 1 dB/cm. Estimates of the switching speed indicate...

  5. Angular dependent light emission from planar waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Peter, Jaison, E-mail: jaison.peter@gmail.com [International School of Photonics, Cochin University of Science and Technology, Cochin 682022 (India); CRE" +E, IDEAS Research Institute, Robert Gordon University, Aberdeen AB10 7GJ (United Kingdom); Prabhu, Radhakrishna [CRE" +E, IDEAS Research Institute, Robert Gordon University, Aberdeen AB10 7GJ (United Kingdom); Radhakrishnan, P.; Vallabhan, C. P. G.; Nampoori, V. P. N.; Kailasnath, M. [International School of Photonics, Cochin University of Science and Technology, Cochin 682022 (India)

    2015-01-07

    We have investigated the angular dependence of amplified spontaneous emission (ASE) and laser emission from an asymmetric and free-standing polymer thin films doped with rhodamine 6G, which is transversely pumped by a pulsed Nd:YAG laser. A semi-leaky waveguide or quasi-waveguide structure has been developed by spin coating technique. In these waveguides, the light was confined by the film/air-film/glass substrate interfaces. At the film/substrate interface, a portion of light will reflect back into the film (guided mode) and the remaining refracted to the substrate resulting in cutoff modes. A blue-shift in ASE has been observed when the pump power was increased from 8 to 20 mW allowing a limited range of tuning of emission wavelength. To study the directionality of the ASE from the waveguide, we have measured the output intensity and FWHM of emission spectra as a function of viewing angle (θ) from the plane parallel to film. From the detailed examination of the output emission spectra, as +θ increases from 0° there has been an initial decrease in output intensity, but at a particular angle ≈10° an increase in output intensity was observed. This additional peak in output intensity as +θ is a clear indication of coexistence of the cutoff mode. We also present a compact solid-state laser based on leaky mode propagation from the dye-doped polymer free-standing film (∼50 μm thickness) waveguide. The partial reflections from the broad lateral surfaces of the free-standing films provided the optical feedback for the laser emission with high directionality. For a pump power of 22 mW, an intense line with FWHM <0.2 nm was observed at 578 nm.

  6. Planar waveguides and other confined geometries theory, technology, production, and novel applications

    CERN Document Server

    2015-01-01

    This book provides a comprehensive overview of the theoretical concepts and experimental applications of planar waveguides and other confined geometries, such as optical fibres. Covering a broad array of advanced topics, it begins with a sophisticated discussion of planar waveguide theory, and covers subjects including efficient production of planar waveguides, materials selection, nonlinear effects, and applications including species analytics down to single-molecule identification, and thermo-optical switching using planar waveguides. Written by specialists in the techniques and applications covered, this book will be a useful resource for advanced graduate students and researchers studying planar waveguides and optical fibers.

  7. Strongly Confined Spoof Surface Plasmon Polaritons Waveguiding Enabled by Planar Staggered Plasmonic Waveguides

    Science.gov (United States)

    Ye, Longfang; Xiao, Yifan; Liu, Yanhui; Zhang, Liang; Cai, Guoxiong; Liu, Qing Huo

    2016-12-01

    We demonstrate a novel route to achieving highly efficient and strongly confined spoof surface plasmon polaritons (SPPs) waveguides at subwavelength scale enabled by planar staggered plasmonic waveguides (PSPWs). The structure of these new waveguides consists of an ultrathin metallic strip with periodic subwavelength staggered double groove arrays supported by a flexible dielectric substrate, leading to unique staggered EM coupling and waveguiding phenomenon. The spoof SPP propagation properties, including dispersion relations and near field distributions, are numerically investigated. Furthermore, broadband coplanar waveguide (CPW) to planar staggered plasmonic waveguide (PSPW) transitions are designed to achieve smooth momentum matching and highly efficient spoof SPP mode conversion. By applying these transitions, a CPW-PSPW-CPW structure is designed, fabricated and measured to verify the PSPW’s propagation performance at microwave frequencies. The investigation results show the proposed PSPWs have excellent performance of deep subwavelength spoof SPPs confinement, long propagation length and low bend loss, as well as great design flexibility to engineer the propagation properties by adjusting their geometry dimensions and material parameters. Our work opens up a new avenue for development of various advanced planar integrated plasmonic devices and circuits in microwave and terahertz regimes.

  8. Mid-IR acoustooptic interaction in planar waveguides

    Science.gov (United States)

    Deriugin, L. N.; Anikin, V. I.; Gudzenko, A. I.; Dneprovskii, V. G.; Terichev, V. F.

    1980-04-01

    The interaction of surface acoustic waves (SAW) and surface optical waves in planar infrared waveguides has been studied experimentally at a wavelength of 10.6 microns, corresponding to the output wavelength of a CO2 laser. In the planar waveguide used, the supporting layer was a film of As-Se chalcogenide glass deposited by thermal evaporation on a substrate of a high-resistivity cadmium sulfide single crystal. Diffraction efficiency vs acoustic power and diffraction efficiency vs SAW frequency plots are presented. The maximum intensity of the diffracted light was observed when the infrared light was incident on the acoustic column at an angle of 1 deg 59 min, which is in good agreement with the calculated value.

  9. Graphene Q-switched Yb:KYW planar waveguide laser

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jun Wan; Young Choi, Sun; Jun Ahn, Kwang; Yeom, Dong-Il, E-mail: diyeom@ajou.ac.kr, E-mail: rotermun@ajou.ac.kr; Rotermund, Fabian, E-mail: diyeom@ajou.ac.kr, E-mail: rotermun@ajou.ac.kr [Department of Energy Systems Research and Department of Physics, Ajou University, 443-749 Suwon (Korea, Republic of); Aravazhi, Shanmugam; Pollnau, Markus [Integrated Optical Micro Systems Groups, MESA+ Institute of Nanotechnology, University of Twente, 7500 AE Enschede (Netherlands); Griebner, Uwe; Petrov, Valentin [Max-Born-Institute for Nonlinear Optics and Short Pulse Spectroscopy, 12489 Berlin (Germany); Bae, Sukang [Soft Innovative Materials Research Center, Korea Institute of Science and Technology, Jeonbuk 565-905 (Korea, Republic of)

    2015-01-15

    A diode-pumped Yb:KYW planar waveguide laser, single-mode Q-switched by evanescent-field interaction with graphene, is demonstrated for the first time. Few-layer graphene grown by chemical vapor deposition is transferred onto the top of a guiding layer, which initiates stable Q-switched operation in a 2.4-cm-long waveguide laser operating near 1027 nm. Average output powers up to 34 mW and pulse durations as short as 349 ns are achieved. The measured output beam profile, clearly exhibiting a single mode, agrees well with the theoretically calculated mode intensity distribution inside the waveguide. As the pump power is increased, the repetition rate and pulse energy increase from 191 to 607 kHz and from 7.4 to 58.6 nJ, respectively, whereas the pulse duration decreases from 2.09 μs to 349 ns.

  10. Graphene Q-switched Yb:KYW planar waveguide laser

    Directory of Open Access Journals (Sweden)

    Jun Wan Kim

    2015-01-01

    Full Text Available A diode-pumped Yb:KYW planar waveguide laser, single-mode Q-switched by evanescent-field interaction with graphene, is demonstrated for the first time. Few-layer graphene grown by chemical vapor deposition is transferred onto the top of a guiding layer, which initiates stable Q-switched operation in a 2.4-cm-long waveguide laser operating near 1027 nm. Average output powers up to 34 mW and pulse durations as short as 349 ns are achieved. The measured output beam profile, clearly exhibiting a single mode, agrees well with the theoretically calculated mode intensity distribution inside the waveguide. As the pump power is increased, the repetition rate and pulse energy increase from 191 to 607 kHz and from 7.4 to 58.6 nJ, respectively, whereas the pulse duration decreases from 2.09 μs to 349 ns.

  11. Coupling of spatially partially coherent beams into planar waveguides.

    Science.gov (United States)

    Partanen, Henri; Tervo, Jani; Turunen, Jari

    2015-03-23

    The second-order coherence theory of partially spatially coherent light and the overlap integral method are applied to study the end-coupling of stationary multimode light beams into planar waveguides. A method is presented for the determination of the cross-spectral density function of the guided field. Examples are given on the effects of spatial coherence, lateral shift, angular tilt, and defocusing of the incident beam on the coupling efficiency, spatial coherence, and propagation characteristics of the guided field.

  12. Cr:ZnSe planar waveguide mid-IR laser

    Science.gov (United States)

    Willimas, J. E.; Martyshkin, D. V.; Fedorov, V. V.; Moskalev, I. S.; Camata, R. P.; Mirov, S. B.

    2011-02-01

    Middle infrared (mid-IR) chromium-doped zinc selenide (Cr:ZnSe) bulk lasers have attracted a lot of attention due to their unique combination of optical and laser properties facilitating a wide range of potential scientific, industrial, and medical applications. Utilization of thin film waveguide geometry enabling good thermal management and control of beam quality is a viable pathway for compact chip-integrated optical laser design. Cr:ZnSe thin films are also promising as saturable absorbers and mode-lockers of the cavities of solid state lasers operating over 1.3-2.1 μm. We recently reported the first successful demonstration of mid-IR Cr:ZnSe planar waveguide lasing at 2.6 μm under gain-switched short-pulse (5 ns) 1.56 μm excitation as well as the passive Q-switching of the cavity of a fiber-pumped Er:YAG laser operating at 1645 nm using a highly doped Cr:ZnSe thin film. PLD grown Cr:ZnSe waveguide were fabricated on sapphire substrates (Cr:ZnSe/sapphire) with chromium concentration of 1018-1019 cm-3. Further development of mid-IR lasing in the Cr:ZnSe planar waveguide under continuous wave excitation were investigated. In addition, deposition of Cr:ZnSe-based thin film structures on n-type GaAs substrates were also investigated for possible mid-IR electroluminescence.

  13. Fabrication and Determination of Refractive Index Profile of the Planar Waveguides by Wedge Technique

    Institute of Scientific and Technical Information of China (English)

    S.; M.; R.; Sadat; Hosseini; A.; Darudi

    2003-01-01

    Several planar waveguides have been fabricated. The waveguides have been polished for determination of their refractive index profiles (RIP) by wedge method. The RIP determined by inserting the sample in a Mach-Zehnder interferometer and applying fringe analysis methods.

  14. Fabrication and Determination of Refractive Index Profile of the Planar Waveguides by Wedge Technique

    Institute of Scientific and Technical Information of China (English)

    S. M. R. Sadat Hosseini; A. Darudi

    2003-01-01

    Several planar waveguides have been fabricated. The waveguides have been polished for determination of their refractiveindex profiles (RIP) by wedge method. The RIP determined by inserting the sample in a Mach-Zehnder interferometer andapplying fringe analysis methods.

  15. Integrated planar optical waveguide interferometer biosensors: a comparative review.

    Science.gov (United States)

    Kozma, Peter; Kehl, Florian; Ehrentreich-Förster, Eva; Stamm, Christoph; Bier, Frank F

    2014-08-15

    Integrated planar optical waveguide interferometer biosensors are advantageous combinations of evanescent field sensing and optical phase difference measurement methods. By probing the near surface region of a sensor area with the evanescent field, any change of the refractive index of the probed volume induces a phase shift of the guided mode compared to a reference field typically of a mode propagating through the reference arm of the same waveguide structure. The interfering fields of these modes produce an interference signal detected at the sensor׳s output, whose alteration is proportional to the refractive index change. This signal can be recorded, processed and related to e.g. the concentration of an analyte in the solution of interest. Although this sensing principle is relatively simple, studies about integrated planar optical waveguide interferometer biosensors can mostly be found in the literature covering the past twenty years. During these two decades, several members of this sensor family have been introduced, which have remarkably advantageous properties. These entail label-free and non-destructive detection, outstandingly good sensitivity and detection limit, cost-effective and simple production, ability of multiplexing and miniaturization. Furthermore, these properties lead to low reagent consumption, short analysis time and open prospects for point-of-care applications. The present review collects the most relevant developments of the past twenty years categorizing them into two main groups, such as common- and double path waveguide interferometers. In addition, it tries to maintain the historical order as it is possible and it compares the diverse sensor designs in order to reveal not only the development of this field in time, but to contrast the advantages and disadvantages of the different approaches and sensor families, as well.

  16. Evanescent planar waveguide detection of biological warfare simulants

    Science.gov (United States)

    Sipe, David M.; Schoonmaker, Kenneth P.; Herron, James N.; Mostert, Michael J.

    2000-04-01

    An evanescent planar waveguide Mark 1.5 instrument was used to detect simulants of biological warfare agents; ovalbumin (OV), MS2 bacteriophage, BG, and Erwinia herbicola (EH). Polyclonal tracer antibodies were labeled with the fluorescent dye, Cy5. Discrete bands of polyclonal capture antibodies were immobilized to a polystyrene planar waveguide with molded integral lenses. An ST-6 CCD camera was used for detection. OV. MS2 and BG were detected in a simultaneous 3 by 3 array; with a total of nine measurements within 6 minutes. EH was analyzed in a separate array. Results were evaluate dat the US Army Joint Field Trials V, at the Dugway Proving Grounds. Over a 10 day period, 32 unknown samples were analyzed daily for each simulant. Detection limits: OV 10 ng/ml, MS2 107 pfu/ml, BG 105 cfu/ml. EH was detectable at 5 X 105 cfu/ml. Overall false positives were 3.0 percent. Therefore, the Mark 1.5 instrument, with a parallel array of detectors, evanescent flourescent excitation, and CCD imaging provides for rapid, sensitive, and specific detection of biological warfare agent simulants.

  17. Effects of the Planar Optical Waveguide Thickness on the Transmission Attenuation①

    Institute of Scientific and Technical Information of China (English)

    WANGJian; SUHansong

    1997-01-01

    By analyzing and computing,according to the wave theory of planar optical waveguide attenuation,a new opinion is put forward.A series of transmission atteenuation with waveguide film-thickness are given and it illustrates that optical transmission is not carrying out efficiently within some waveguide film-thickness.

  18. Directly UV-written silica-on-silicon planar waveguides with low insertion loss

    DEFF Research Database (Denmark)

    Zauner, Dan; Kulstad, K.; Rathje, Jacob;

    1998-01-01

    The coupling loss between directly W-written planar waveguides and standard telecom fibre has been reduced by index matching the three layer structure used for UV writing. Insertion losses down to 0.1 dB for 3 cm long waveguides have been achieved.......The coupling loss between directly W-written planar waveguides and standard telecom fibre has been reduced by index matching the three layer structure used for UV writing. Insertion losses down to 0.1 dB for 3 cm long waveguides have been achieved....

  19. Uniform Core Field in Symmetrical Planar Waveguides and Circular Fibers with Nonlinear Claddings

    Institute of Scientific and Technical Information of China (English)

    庞霖; 严瑛白; 金国藩; 邬敏贤; 郭履容; 陈波

    2001-01-01

    It is known that no uniform electric field profile exists in a planar linear waveguide. The uniform core field can be shown to exist in symmetrical planar waveguides and circular fibers with nonlinear claddings. Theoretical analysis and numerical calculations are carried out to show that when the modal index equals to the core refractive-index, the core field becomes uniform at an appropriate optical power. Analysis for a step-index circular fiber with nonlinear cladding have also shown that the core field becomes uniform under similar conditions. The occurrence of a uniform field in a waveguide core may believe to have promising applications in waveguide, optoelectronic and photonic devices.

  20. Direct characterization of planar waveguide modes by Fourier plane fluorescence leakage radiation microscopy

    CERN Document Server

    Zhang, Douguo; Wang, Xiangxian; Wang, Pei; Ming, Hai

    2011-01-01

    In this letter, the leakage radiation microscopy (LRM) is extended into characterization of planar waveguide modes (WMs) rather than surface plasmon polaritons (SPPs) taking advantages of the coupling between WMs and fluorescence emission. Propagation constants of different WMs allowed in the same planar waveguide can be simultaneously and rapidly derived from the Fourier plane image of fluorescence based LRM. Numerical simulations are also carried out to calculate propagation constants of these modes, which are consistent with experimental results. Our experiments provide a simple but high efficient method to characterize planar waveguides.

  1. Waveguide Phase Modulator for Integrated Planar Lightwave Circuits in KTP Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR Phase I effort proposes the development of a potassium titanyl phosphate (KTP) waveguide phase modulator for future integration into a Planar Lightwave...

  2. Analytic Matrix Method for the Study of Propagation Characteristics of a Bent Planar Waveguide

    Institute of Scientific and Technical Information of China (English)

    LIU Qing; CAO Zhuang-Qi; SHEN Qi-Shun; DOU Xiao-Ming; CHEN Ying-Li

    2000-01-01

    An analytic matrix method is used to analyze and accurately calculate the propagation constant and bendinglosses of a bent planar waveguide. This method gives not only a dispersion equation with explicit physical insight,but also accurate complex propagation constants.

  3. Loss-Less planar waveguide 1:4 power splitter at 1550 nm

    DEFF Research Database (Denmark)

    Sckerl, Mads W.; Guldberg-Kjær, Søren Andreas; Laurent-Lund, Christian

    1999-01-01

    By a unique desposition/etching technique an erbuim-doped planar silica waveguide with intergrated splitter on a silicon substrate was produced and is demonstrated to show net gain at 1550 nm and good saturation and noise characteristics....

  4. Planar waveguide Bragg grating sensors for composite monitoring

    Science.gov (United States)

    Teigell Benéitez, Nuria; Missinne, Jeroen; Chiesura, Gabriele; Luyckx, Geert; Degrieck, Joris; Van Steenberge, Geert

    2016-04-01

    Composite materials are extensively used in a wide array of application markets by virtue of their strength, stiffness and lightness. Many composite structures are replaced today not only after failure but also before, for precautionary reasons. Adding optical sensing intelligence to these structures not only prolongs their lifetime but also significantly reduces the use of raw materials and energy. The use of optical based sensors offer numerous advantages i.e. integrability, high sensitivity, compactness and electromagnetic immunity. Most sensors integrated in composites are based on silica fibers with Bragg gratings. However, polymers are an interesting alternative because they present several advantages. They have high values in the opticalconstants involved in sensing, are cost-effective and allow larger elongations than silica. Moreover, planar optical waveguides represent an interesting approach to be further integrated e.g. in circuits. We present a comparison between Ormocer®-based and epoxy-based polymer waveguide Bragg grating sensors. Both polymers were screened for their compatibility with composite production processes and for their sensitivity to measure temperature and stress. Ormocer®-based sensors were found to exhibit a very high sensitivity (-250 pm/°C) for temperature sensing, while the epoxy-based sensors, although less sensitive (-90 pm/°C) were more compatible with the epoxy-based composite production process. In terms of sensitivity to measure stress, both materials were found to be analogous with measured values of (2.98 pm/μepsilon) for the epoxy-based and (3.00 pm/μepsilon) for Ormocer®-based sensors.

  5. Mid-IR laser oscillation in Cr2+:ZnSe planar waveguide.

    Science.gov (United States)

    Williams, J E; Fedorov, V V; Martyshkin, D V; Moskalev, I S; Camata, R P; Mirov, S B

    2010-12-06

    We demonstrate 2.6 µm mid-infrared lasing at room temperature in a planar waveguide structure. Planar waveguides were fabricated using pulsed laser deposition (PLD) by depositing chromium doped zinc selenide thin films on sapphire substrate (Cr2+:ZnSe/sapphire). Highly doped Cr2+:ZnSe/Sapphire thin film sample was also used to demonstrate passive Q-switching of Er:YAG laser operating at 1.645 µm.

  6. Block Copolymer Directed Self-Assembly Approaches for Doping Planar and Non-Planar Semiconductors

    Science.gov (United States)

    Popere, Bhooshan; Russ, Boris; Heitsch, Andrew; Trefonas, Peter; Segalman, Rachel

    As electronic circuits continue to shrink, reliable nanoscale doping of functional devices presents new challenges. While directed self-assembly (DSA) of block copolymers (BCPs) has enabled excellent pitch control for lithography, controlling the 3D dopant distribution remains a fundamental challenge. To this end, we have developed a BCP self-assembly approach to confine dopants to nanoscopic domains within a semiconductor. This relies on the supramolecular encapsulation of the dopants within the core of the block copolymer (PS- b-P4VP) micelles, self-assembly of these micelles on the substrate, followed by rapid thermal diffusion of the dopants into the underlying substrate. We show that the periodic nature of the BCP domains enables precise control over the dosage and spatial position of dopant atoms on the technologically relevant length scales (10-100 nm). Additionally, as the lateral density of 2D circuit elements approaches the Moore's limit, novel 3D architectures have emerged. We have utilized our BCP self-assembly approach towards understanding the self-assembly our micelles directed by such nanoscale non-planar features. We show that the geometric confinement imposed by the hard feature walls directs the assembly of these micelles.

  7. Integrated optical components based on planar photonic crystal waveguides with perturbed border holes

    DEFF Research Database (Denmark)

    Niemi, Tapio; Frandsen, Lars Hagedorn; Harpøth, Anders;

    2005-01-01

    In this work, we have experimentally and by simulations investigated the effect of making small perturbations of the size of the border holes adjacent to the planar photonic crystal waveguide (PCW). The waveguide is created by removing one row of holes in the nearest-neighbour direction of air ho...

  8. theoretical analysis of finite-height semiconductor-on-insulator based planar photonic crystal waveguides

    DEFF Research Database (Denmark)

    Søndergaard, Thomas; Arentoft, Jesper

    2002-01-01

    A planar photonic crystal waveguide based on the semiconductor-on-insulator (SOI) materials system is analyzed theoretically. Two-dimensional (2-D) calculations and comparison with dispersion relations for the media above and below the finite-height waveguide are used to obtain design guidelines...

  9. Numerical Method for Analysis of Waveguide Modes in Planar Gradient Waveguides

    Directory of Open Access Journals (Sweden)

    Volodymyr Mykhailovych FITIO

    2014-09-01

    Full Text Available This paper presents a numerical method developed to find propagation constants of planar waveguide localized modes. The method is based on both the Fourier transform application and the wave equation solution in a frequency domain. As a result, integral equation is obtained where integral is replaced by sum. Finally, a task to find propagation constants and field Fourier transforms in a discrete form is led to the eigenvalue/eigenvector problem. This method provides high accuracy subject to the conditions of the Whittaker-Shannon sampling theorem, and it is characterized by high numerical stability. The method is tested on many examples. DOI: http://dx.doi.org/10.5755/j01.ms.20.3.4841

  10. Single-mode fiber linearly tapered planar waveguide tunable coupler

    Science.gov (United States)

    Das, Alok K.; Hussain, Anwar

    1997-09-01

    We developed a simple system of tunable fiber film coupler using a linearly tapered thin-film planar waveguide (PWG) evanescently coupled by a single-mode distributed fiber half-coupler. We investigate the characteristics of the coupler theoretically and experimentally taking into consideration the refractive index ( n f ) of nonuniform films, the magnitude of nonuniformity ( m ) of the films, and the source wavelength ( ). The thickness variation of the nonuniform film is along the direction of propagation of optical power. Tapered and plano concave thin films of a mix of oils as well as a plano concave poly(methyl methacrylate) film were fabricated to serve as nonuniform PWG s. Similar to single-mode fiber with a uniform thickness PWG coupler, such a coupler also provides light modulation with a change of n f . However, position shifting of a half-coupler in a tapered PWG structure along the direction of propagation exhibits the variation of fiber throughput power. This action serves as a simple system for a tunable fiber film coupler. Wavelength-dependent throughput fiber power for such a coupler also behaves as a filter. The center wavelength can be controlled by shifting the position of the half-coupler. A coupling fiber as a half-coupler can be used for efficient coupling. We performed a theoretical analysis of the structure using Marcuse s model and observed good agreement with the experimental results.

  11. Optimal design of a spectral readout type planar waveguide-mode sensor with a monolithic structure.

    Science.gov (United States)

    Wang, Xiaomin; Fujimaki, Makoto; Kato, Takafumi; Nomura, Ken-Ichi; Awazu, Koichi; Ohki, Yoshimichi

    2011-10-10

    Optical planar waveguide-mode sensor is a promising candidate for highly sensitive biosensing techniques in fields such as protein adsorption, receptor-ligand interaction and surface bacteria adhesion. To make the waveguide-mode sensor system more realistic, a spectral readout type waveguide sensor is proposed to take advantage of its high speed, compactness and low cost. Based on our previously proposed monolithic waveguide-mode sensor composed of a SiO2 waveguide layer and a single crystalline Si layer [1], the mechanism for achieving high sensitivity is revealed by numerical simulations. The optimal achievable sensitivities for a series of waveguide structures are summarized in a contour map, and they are found to be better than those of previously reported angle-scan type waveguide sensors.

  12. Ray analysis of parabolic-index segmented planar waveguides.

    Science.gov (United States)

    Rastogi, V; Ghatak, A K; Ostrowsky, D B; Thyagarajan, K; Shenoy, M R

    1998-07-20

    A ray analysis of periodically segmented waveguides with parabolic-index variation in the high-index region is presented. We carried out the analysis using ray transfer matrices, which is convenient to implement and which can be extended to study different types of graded-index segmented waveguide. Results of this ray tracing approach clearly illustrate the waveguiding properties and the existence of stable and unstable regions of operation in segmented waveguides. We also illustrate the tapering action exhibited by segmented waveguides in which the duty cycle varies along the length of the waveguide. This analysis, although restricted to multimode structures, provides a clear visualization of the waveguiding properties in terms of ray propagation in segmented waveguides.

  13. A waveguide polarizer based on Si-coated Ti:LiNbO3 planar structure

    Institute of Scientific and Technical Information of China (English)

    Hangyou Lin(林航友); Jiping Ning(宁继平); Fan Geng(耿凡)

    2004-01-01

    @@ A novel design of a transverse magnetic(TM)-pass waveguide polarizer based on Si on an X-cut,Y-propagatiou Ti:LiNbO3 planar waveguide is presented.The eigenvalue functions of such structure havebeen obtained by using Wenzel-Kramers-Brillouin(WKB)method with modified Airy functions.Theintervals of the silicon thickness have been found which result in transverse electric(TE)light sufferingstrong attenuation while TM wave propagating with fairly low loss.A planar waveguide polarizer isfabricated and its polarization-dependent measurements lead to the best polarization extinction ratio~34dB and the insertion loss<0.4 dB.

  14. Optical planar waveguides in Yb3+-doped phosphate glasses produced by He+ ion implantation

    Institute of Scientific and Technical Information of China (English)

    Liu Chun-Xiao; Li Wei-Nan; Wei Wei; Peng Bo

    2012-01-01

    Optical planar waveguides in Yb3+-doped phosphate glasses are fabricated by implanting triple-energy helium ions.The guiding modes and the near-field intensity distribution are measured by using the prism-coupling method and the end-face coupling setup with a He-Ne laser at 633 nm The intensity calculation method (ICM) is used to reconstruct the refractive index profile of the waveguide.The absorption and the fluorescence investigations reveal that the glass bulk features are well preserved in the active volumes of the waveguides,suggesting the fabricated structures for possible applications as waveguide lasers.

  15. NONLINEAR OPTICS: Nonlinear optical processes in planar waveguides and excitation of surface polaritons

    Science.gov (United States)

    Yashkir, O. V.; Yashkir, Yu N.

    1987-11-01

    An investigation is made of nonlinear optical interaction of light propagating in a planar waveguide with surface polaritons. Reduced wave equations for the amplitudes of the waveguide modes and surface polaritons are used to study the characteristics of generation of surface polaritons of difference frequency, parametric frequency up-conversion of the polaritons, and stimulated Raman scattering by the polaritons. An analysis is made of the characteristic properties of the investigated nonlinear optical processes.

  16. Planar Bragg gratings made by excimer-laser modification of ion-exchanged waveguides.

    Science.gov (United States)

    Montero, C; Gomez-Reino, C; Brebner, J L

    1999-11-01

    The refractive indices of planar silver-ion-exchanged waveguides have been modified by UV excimer laser irradiation (lambda=193 nm) . The effective index changes of the fundamental modes of the waveguides after exposition are as large as 2x10(-2) . The procedure permits the fabrication of integrated optical components in a direct way, with neither the use of standard lithography nor previous sensitizing of the substrate. Optical characterization of the irradiated samples is presented. By the use of appropriate masks, we have fabricated planar Bragg gratings.

  17. Error-free 640 Gbit/s demultiplexing using a chalcogenide planar waveguide chip

    DEFF Research Database (Denmark)

    Xu, Jing; Galili, Michael; Mulvad, Hans Christian Hansen;

    2008-01-01

    We demonstrate error free, low-penalty demultiplexing of a 640 Gbit/s OTDM signal to 10 Gbit/s using a 5cm long chalcogenide planar waveguide chip. Our approach exploits four-wave mixing by the instantaneous nonlinear response of chalcogenide.......We demonstrate error free, low-penalty demultiplexing of a 640 Gbit/s OTDM signal to 10 Gbit/s using a 5cm long chalcogenide planar waveguide chip. Our approach exploits four-wave mixing by the instantaneous nonlinear response of chalcogenide....

  18. Structures of 3-layer planar waveguide where core field can become uniform

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Theoretical analysis and numerical results for typical examples are presented for three-layer planar waveguides with nonlinear claddings to find the appropriate structures in which the core electric field can become uniform at appropriate optical power while the cladding fields decay exponentially. It is shown that there are five kinds of such structures. The electric field profiles are plotted for the five typical examples. We notify that the occurrence of uniform field in a waveguide core may perhaps have prospective applications in waveguide, opto-electronic and photonic devices.

  19. Ceramic planar waveguide laser of non-aqueous tape casting fabricated YAG/Yb:YAG/YAG.

    Science.gov (United States)

    Wang, Chao; Li, Wenxue; Yang, Chao; Bai, Dongbi; Li, Jiang; Ge, Lin; Pan, Yubai; Zeng, Heping

    2016-08-18

    Ceramic YAG/Yb:YAG/YAG planar waveguide lasers were realized on continuous-wave and mode-locked operations. The straight waveguide, fabricated by non-aqueous tape casting and solid state reactive sintering, enabled highly efficient diode-pumped waveguide continuous-wave laser with the slope efficiency of 66% and average output power of more than 3 W. The influence of the waveguide structure on the wavelength tunability was also experimentally investiccgated with a dispersive prism. Passively mode-locked operation of the ceramic waveguide laser was achieved by using a semiconductor saturable absorber mirror (SESAM), output 2.95 ps pulses with maximum power of 385 mW at the central wavelength of 1030 nm.

  20. Refractive index engineering with subwavelength gratings for efficient microphotonic couplers and planar waveguide multiplexers.

    Science.gov (United States)

    Cheben, Pavel; Bock, Przemek J; Schmid, Jens H; Lapointe, Jean; Janz, Siegfried; Xu, Dan-Xia; Densmore, Adam; Delâge, André; Lamontagne, Boris; Hall, Trevor J

    2010-08-01

    We use subwavelength gratings (SWGs) to engineer the refractive index in microphotonic waveguides, including practical components such as input couplers and multiplexer circuits. This technique allows for direct control of the mode confinement by changing the refractive index of a waveguide core over a range as broad as 1.6-3.5 by lithographic patterning. We demonstrate two experimental examples of refractive index engineering, namely, a microphotonic fiber-chip coupler with a coupling loss as small as -0.9dB and minimal wavelength dependence and a planar waveguide multiplexer with SWG nanostructure, which acts as a slab waveguide for light diffracted by the grating, while at the same time acting as a lateral cladding for the strip waveguide. This yields an operation bandwidth of 170nm for a device size of only approximately 160microm x100microm.

  1. Monolithic DWDM Multi-channel planar waveguide laser

    DEFF Research Database (Denmark)

    Sckerl, Mads W.; Guldberg-Kjær, Søren Andreas; Laurent-Lund, Christian

    1999-01-01

    silica -on-silicon-based multi-channel waveguide laser with four outputs channel with ~ 50 GHz spacing is presented. Excellent control over channel positions and spacings is obtained by the method presented here. Remarkable temperature tuning properties have been obtained.......silica -on-silicon-based multi-channel waveguide laser with four outputs channel with ~ 50 GHz spacing is presented. Excellent control over channel positions and spacings is obtained by the method presented here. Remarkable temperature tuning properties have been obtained....

  2. FIBER-OPTIC AND OTHER WAVEGUIDES: Characteristics of nonlinear optical excitation of modes in planar waveguide structures

    Science.gov (United States)

    Yashkir, O. V.; Yashkir, Yu N.

    1987-06-01

    A theoretical investigation is made of nonlinear excitation of planar waveguide modes at frequencies ω when external plane optical waves of frequency ω1 are incident on the waveguide surface. The general formulas for the efficiency of the excitation of modes by a monochromatic wave are obtained and analyzed for the case of self-interaction of the ω = ω1 + ω1 - ω1 type and by a biharmonic wave in the case of generation of the difference frequency ω = ω1 - ω1'. The efficiency of parametric conversion of waveguide modes ω accompanied by an increase of the frequency to the range ω' is considered for the case when the sum frequency ω + ω1 = ω1' is generated. The numerical method developed by the authors is used to analyze the characteristic features of these processes in some specific cases.

  3. Optical coupling of bare optoelectronic components and flexographically printed polymer waveguides in planar optronic systems

    Science.gov (United States)

    Wang, Yixiao; Wolfer, Tim; Lange, Alex; Overmeyer, Ludger

    2016-05-01

    Large scale, planar optronic systems allowing spatially distributed functionalities can be well used in diverse sensor networks, such as for monitoring the environment by measuring various physical quantities in medicine or aeronautics. In these systems, mechanically flexible and optically transparent polymeric foils, e.g. polymethyl methacrylate (PMMA) and polyethylene terephthalate (PET), are employed as carrier materials. A benefit of using these materials is their low cost. The optical interconnections from light sources to light transmission structures in planar optronic systems occupy a pivotal position for the sensing functions. As light sources, we employ the optoelectronic components, such as edgeemitting laser diodes, in form of bare chips, since their extremely small structures facilitate a high integration compactness and ensure sufficient system flexibility. Flexographically printed polymer optical waveguides are deployed as light guiding structures for short-distance communication in planar optronic systems. Printing processes are utilized for this generation of waveguides to achieve a cost-efficient large scale and high-throughput production. In order to attain a high-functional optronic system for sensing applications, one of the most essential prerequisites is the high coupling efficiency between the light sources and the waveguides. Therefore, in this work, we focus on the multimode polymer waveguide with a parabolic cross-section and investigate its optical coupling with the bare laser diode. We establish the geometrical model of the alignment based on the previous works on the optodic bonding of bare laser diodes and the fabrication process of polymer waveguides with consideration of various parameters, such as the beam profile of the laser diode, the employed polymer properties of the waveguides as well as the carrier substrates etc. Accordingly, the optical coupling of the bare laser diodes and the polymer waveguides was simulated

  4. On the spectrum of waveguides in planar photonic bandgap structures

    CERN Document Server

    Brown, Malcolm; Plum, Michael; Wood, Ian

    2012-01-01

    We study a Helmholtz-type spectral problem related to the propagation of electromagnetic waves in photonic crystal waveguides. The waveguide is created by introducing a linear defect into a two-dimensional periodic medium. The defect is infinitely extended and aligned with one of the coordinate axes. The perturbation is expected to introduce guided mode spectrum inside the band gaps of the fully periodic, unperturbed spectral problem. In the first part of the paper, we prove that, somewhat unexpectedly, guided mode spectrum can be created by arbitrarily "small" perturbations. Secondly we show that, after performing a Floquet decomposition in the axial direction of the waveguide, for any fixed value of the quasi-momentum $k_x$ the perturbation generates at most finitely many new eigenvalues inside the gap.

  5. A simple model for fibre optics: planar dielectric waveguides in rotation

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Ocon, F [Departamento de Optica, Universidad de Granada, 18071 Granada (Spain); Pena, A [Valeo Iluminacion, 23600 Martos, Jaen (Spain); Jimenez, J R [Departamento de Optica, Universidad de Granada, 18071 Granada (Spain); Diaz, J A [Departamento de Optica, Universidad de Granada, 18071 Granada (Spain)

    2006-05-01

    In planar dielectric waveguides, there is only one type of propagated ray: the one that crosses the waveguide axis after each total internal reflection. According to the model of geometrical optics, there are two types of guided ray in fibre optics: meridional and skew. Each one is formulated by a suitable mathematical treatment. In this work, we demonstrate that the complex mathematical treatment for the skew rays can be avoided by considering a planar waveguide (with the same refractive index profile as the fibre and thickness equal to its diameter) that rotates around the direction of the axis with angular velocity {omega}. A section of this fibre is inscribed in the hypothetical slab. This model has been successfully introduced to students of engineering and physics.

  6. Mid-infrared supercontinuum generation in tapered As2S3 chalcogenide planar waveguide

    Science.gov (United States)

    Zhang, Xiang; Hu, Hongyu; Li, Wenbo; Dutta, Niloy K.

    2016-10-01

    We numerically demonstrate mid-infrared supercontinuum generation in a non-uniformly tapered chalcogenide planar waveguide. This planar rib waveguide of As2S3 glass on MgF2 is 2 cm long with increasing etch depth longitudinally to manage the total dispersion. This waveguide has zero dispersion at two wavelengths. The dispersion profile varies along the propagation distance, leading to continuous modification of the phase-matching condition for dispersive wave emission and enhancement of energy transfer efficiency between solitons and dispersive waves. Numerical simulations are conducted for secant input pulses at a wavelength of 1.55 μm with a width of 50 fs and peak power of 2 kW. Results show this proposed scheme significantly broadens the generated continuum, extending from ~1 to ~7 μm.

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

    CERN Document Server

    Pennanen, Antti M; 10.1364/OE.21.000A23

    2012-01-01

    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).

  8. Plasmon-soliton waves in planar slot waveguides: I. Modeling

    CERN Document Server

    Walasik, Wiktor

    2016-01-01

    We present two complementary models to study stationary nonlinear solutions in one-dimensional plasmonic slot waveguides made of a finite-thickness nonlinear dielectric core surrounded by metal regions. The considered nonlinearity is of focusing Kerr type. In the first model, it is assumed that the nonlinear term depends only on the transverse component of the electric field and that the nonlinear refractive index change is small compared to the linear part of the refractive index. This first model allows us to describe analytically the field profiles in the whole waveguide using Jacobi elliptic special functions. It also provides a closed analytical formula for the nonlinear dispersion relation. In the second model, the full dependency of the Kerr nonlinearity on the electric field components is taken into account and no assumption is required on the amplitude of the nonlinear term. The disadvantage of this approach is that the field profiles must be computed numerically. Nevertheless analytical constraints ...

  9. A Compact, Planar, Eight-Port Waveguide Power Divider/Combiner: The Cross Potent Superhybrid

    OpenAIRE

    Nantista, Christopher D.; Tantawi, Sami G.

    2001-01-01

    In this letter, we present a novel four-way divider/combiner in rectangular waveguide. The design is completely two-dimensional in the h-plane, with eight-fold mirror symmetry, and is based on a recent four-port hybrid design [6]. In combining mode, it can function as a phased array with four inputs and four outputs. The planar nature of this design provides advantages, such as the freedom to increase the waveguide height beyond the over-moding limit in order to reduce field strengths. Along ...

  10. Electromagnetic field generated by a modulated moving point source in a planarly layered waveguide

    Science.gov (United States)

    Barrera-Figueroa, V.; Rabinovich, V. S.

    2016-04-01

    In the present work, we consider a modulated point source in an arbitrary motion in an isotropic planarly layered waveguide. The radiation field generated by this source is represented in the form of double oscillatory integrals in terms of the time and the frequency, depending on the large parameter λ. By means of the stationary phase method, we analyze, in the waveguide, the Doppler effect, the retarded time, and the Vavilov-Cherenkov radiation. Numerically, the problem of the moving source is approached by the method of spectral parameter power series.

  11. Chi 3 dispersion in planar tantalum pentoxide waveguides in the telecommunications window.

    Science.gov (United States)

    Chen, Ruiqi Y; Charlton, Martin D B; Lagoudakis, Pavlos G

    2009-04-01

    We report on the dispersion of the third-order nonlinear susceptibility (chi(3) or "Chi 3") in planar Ta2O5 waveguides in the telecommunications spectral window. We utilize the observation of third-harmonic generation under ultrashort pulsed excitation as a reference-free characterization method of chi(3) and obtain a large nonlinear coefficient, 2x10(-13) esu, at 1550 nm. Our observation of efficient third-harmonic generation in Ta2O5 waveguides in the telecoms window reveals the potential of this material system in high-speed integrated nonlinear optical switches.

  12. Driving Rydberg-Rydberg transitions from a co-planar microwave waveguide

    CERN Document Server

    Hogan, S D; Merkt, F; Thiele, T; Filipp, S; Wallraff, A

    2011-01-01

    The coherent interaction between ensembles of helium Rydberg atoms and microwave fields in the vicinity of a solid-state co-planar waveguide is reported. Rydberg-Rydberg transitions, at frequencies between 25 GHz and 38 GHz, have been studied for states with principal quantum numbers in the range 30 - 35 by selective electric-field ionization. An experimental apparatus cooled to 100 K was used to reduce effects of blackbody radiation. Inhomogeneous, stray electric fields emanating from the surface of the waveguide have been characterized in frequency- and time-resolved measurements and coherence times of the Rydberg atoms on the order of 250 ns have been determined.

  13. SOI waveguide based planar reflective grating demultiplexer for FTTH

    Science.gov (United States)

    Bidnyk, S.; Feng, D.; Balakrishnan, A.; Pearson, M.; Gao, M.; Liang, H.; Qian, W.; Kung, C.-C.; Fong, J.; Yin, J.; Asghari, M.

    2007-02-01

    Recent deployments of fiber-to-the-home (FTTH) represent the fastest growing sector of the telecommunication industry. The emergence of the silicon-on-insulator (SOI) photonics presents an opportunity to exploit the wide availability of silicon foundries and high-quality low-cost substrates for addressing the FTTH market. We have now demonstrated that a monolithically integrated FTTH demultiplexer can be built using the SOI platform. The SOI filter comprises a monolithically integrated planar reflective grating and a multi-stage Mach-Zehnder interferometer that were fabricated using a CMOS-compatible SOI process with the core thickness of 3.0 μm and optically insulating layer of silica with a thickness of 0.375 μm. The Mach-Zehnder interferometer was used to coarsely separate the 1310 nm channel from 1490 and 1550 nm channels. Subsequently, a planar reflective grating was used to demultiplex the 1490 and 1550 nm channels. The manufactured device showed the 1-dB bandwidth of 110 nm for the 1310 nm channel. For the 1490 nm and 1550 nm channels, the 1-dB bandwidth was measured to be 30 nm. The adjacent channel isolation between the 1490 nm and 1550 nm channels was better than 32 dB. The optical isolation between the 1310 nm and 1490 and 1550 nm channels was better than 45 dB. Applications of the planar reflective gratings in the FTTH networks are discussed.

  14. PECVD grown multiple core planar waveguides with extremely low interface reflections and losses

    DEFF Research Database (Denmark)

    Laurent-Lund, Christian; Poulsen, Mogens Rysholt; Beukema, Martijn A

    1998-01-01

    A novel and generic method for fabricating silica-on-silicon planar lightwave circuits with cores composed of two or more different types of glasses is described. The basic process technologies used are silane/germane/nitrous-oxide based plasma enhanced chemical vapor deposition and fluorine based...... reactive ion etching. Very high-quality interfaces between the different core glasses are obtained with interface losses as low as 0.022 +/- 0.012 dB and reflection levels below -80 dB. This technique adds flexibility and ease to the design of complex silica planar waveguide components, allowing, e...

  15. Optimized planar photonic crystal waveguide 60° bend with more than 200 nm wide 1-dB transmission bandwidth

    DEFF Research Database (Denmark)

    Kristensen, Martin; Borel, Peter Ingo; Frandsen, Lars Hagedorn;

    2005-01-01

    Topology optimization was used to design a planar photonic crystal waveguide 60o bend leading to a record-breaking transmission bandwidth of more than 200nm. The experimental results agree well with 3D finite-difference-time-domain simulations.......Topology optimization was used to design a planar photonic crystal waveguide 60o bend leading to a record-breaking transmission bandwidth of more than 200nm. The experimental results agree well with 3D finite-difference-time-domain simulations....

  16. Planar waveguide Michelson interferometer fabricated by using 157nm mask laser micromachining

    Science.gov (United States)

    Bao, Haihong; Ran, Zengling; Wu, Xuezhong; Yang, Ke; Jiang, Yuan; Rao, Yunjiang

    2015-07-01

    A Michelson interferometer is fabricated on silica planar waveguide by using the one-step technology based on 157nm mask laser micromachining. The fabrication time for one device is ~10s. Experimental results show that such an interferometer has an excellent fringe contrast of >20dB. Its temperature and refractive index (RI) responses are tested by observing the wavelength shift of the interferometric fringes, which shows linear characteristics with a thermo-coefficient of ~9.5pm/°C and a RI-coefficient of ~36.7nm/RIU, respectively. The fabrication technology may pave a new way for direct writing of planar silica waveguide devices for sensing applications with high efficiency and quality.

  17. Erbium-doped crystalline YAG planar and ridge waveguides on quartz and sapphire substrates: deposition and material characterisation

    Science.gov (United States)

    Facchini, G.; Zappettini, A.; Canali, A.; Martinelli, M.; Gabetta, G.; Tallarida, G.

    2001-06-01

    Er-doped Yttrium-Aluminium-Garnet (YAG) planar and ridge waveguides have been grown on quartz and sapphire substrates. The waveguides have been structurally, morphologically and stoichiometrically characterised by X-ray diffraction, atomic force microscopy and X-ray photoelectron spectroscopy. Doping concentrations up to 5% have been successfully demonstrated. Deposition of channel waveguide on sapphire substrate results in a correct ridge shape.

  18. Sol-gel coatings: An alternative route for producing planar optical waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Rey-Garcia, F.; Gomez-Reino, C. [Unidad Asociada de Optica and Microoptica GRIN (CSIC-ICMA), Departamento de Fisica Aplicada, Escola Universitaria de Optica e Optometria, Universidade de Santiago de Compostela, Campus Sur s/n, E-15782 Santiago de Compostela (Spain); Flores-Arias, M.T., E-mail: maite.flores@usc.es [Unidad Asociada de Optica and Microoptica GRIN (CSIC-ICMA), Departamento de Fisica Aplicada, Escola Universitaria de Optica e Optometria, Universidade de Santiago de Compostela, Campus Sur s/n, E-15782 Santiago de Compostela (Spain); De La Fuente, G.F., E-mail: xerman@unizar.es [Instituto de Ciencia de Materiales de Aragon (CSIC-Universidad de Zaragoza), Maria de Luna 3, E-50018 Zaragoza (Spain); Duran, A. [Instituto de Ceramica y Vidrio (CSIC), Kelsen 5, E-28049, Madrid (Spain); Castro, Y., E-mail: castro@icv.csic.es [Instituto de Ceramica y Vidrio (CSIC), Kelsen 5, E-28049, Madrid (Spain)

    2011-09-01

    Inorganic and hybrid planar waveguides with different compositions (silica-titania, methacrylate-silica-cerium oxide, zirconia-cerium oxide and silica-zirconia) have been obtained by sol-gel synthesis followed by dip-coating. Soda-lime glass slides and conventional commercial window glass were used as substrates. The thickness and refractive index of the coatings were determined by profilometry and Spectroscopic Ellipsometry. Waveguide efficiency was measured at ca. 70.8% with a He-Ne laser beam, coupled with an optical microscope objective into and out of the waveguiding layer via a double prism configuration. Thicknesses between 150 and 2000 nm, along with refractive index values ranging between 1.45 and {approx} 1.99 ({lambda} = 633 nm) were obtained depending on the sol composition and the dip-coating conditions. This wide range of values allows designing multilayered guides that can be used in a variety of applications.

  19. Planar optical waveguides formed in β-BBO by MeV O+ implantation

    Institute of Scientific and Technical Information of China (English)

    WANG Xuelin; WANG Keming; CHEN Feng; LU Qingming; MA Hongji; NIE Rui

    2007-01-01

    The planar waveguides have been fabricated in z-cutβ-B2O4 crystal by 2.8 MeV O+ion implantation with the doses of 8×1014 and 2×1015ions/cm2 at room temperature.The waveguides were characterized by the prismcoupling method.The dark modes are measured before and after the annealing at 300℃ for 20 and 40 min in air.The refractive index profile is reconstructed Using the reflectivity calculation method.It is found that relatively 1arge positive changes of extraordinary refractive indices happen in the guiding regions,and a slight change increases with the doses,which are different from most of the observed ion-implanted waveguides.

  20. Design of Pass Band Filter in Hybrid Architecture Planar/Non-Radiative Dielectric Waveguide Integration Technology

    Directory of Open Access Journals (Sweden)

    Harizi Hanen

    2012-01-01

    Full Text Available Problem statement: The expansion of RF, microwave and millimeter devices has revolutionized today’s ommunication and sensor systems. Low-cost, high-performance and mass producible millimeter wave technologies are vital for commercial broadband systems. Challenging issues are commonly faced in the design of low-loss integrated circuits for example high-Q band pass filter, which the planar technique is fundamentally limited in performance. Approach: In this study, we present a design of a nonradiative dielectric waveguide band pass filter based on hybrid architecture of micro strip line and non-radiative dielectric waveguide. Results: The simulation with High Frequency Structure Simulator (HFSS three dimensional analyses is presented. Conclusion: The non radiative dielectric resolves most of the drawbacks of dielectric waveguide in connection with the radiation loss."

  1. Photoluminescence and attenuation of spray-pyrolysis deposited erbium-doped Y2O3 planar optical waveguides

    NARCIS (Netherlands)

    Hoekstra, T.H.; Hoekstra, T.H.; Hilderink, L.T.H.; Lambeck, Paul; Popma, T.J.A.

    1992-01-01

    Erbium-doped Y20 3 planar optical waveguides have been fabricated by spray-pyrolysis deposition. The attenuation spectrum of the waveguide shows peaks that are due to absorption of the erbium ions. The as-deposited layers also show photoluminescence sharply peaking at 1540 nm with additional Stark

  2. Spectral Volumetric Integral Equation Methods for Acoustic Medium Scattering in a Planar Homogeneous 3D Waveguide

    OpenAIRE

    Lechleiter, Armin; Nguyen, Dinh Liem

    2010-01-01

    Scattering of acoustic waves from an inhomogeneous medium can be described by the Lippmann-Schwinger integral equation. For scattering problems in free space, Vainikko proposed a fast spectral solution method that exploits the convolution structure of this equation's integral operator by using the fast Fourier transform. In a planar 3--dimensional waveguide, the integral operator of the Lippmann-Schwinger integral equation fails to be a convolution. In this paper, we show that the separable s...

  3. Recent progress on arrayed-waveguide grating multi/demultiplexers based on silica planar lightwave circuits

    Science.gov (United States)

    Kitoh, Tsutomu

    2008-11-01

    This paper reports recent advances on arrayed waveguide grating (AWG) multi/demultiplexers based on silica-based planar lightwave circuits (PLC). After briefly summarizing the fabrication and properties of PLCs, this work describes a Mach-Zehnder interferometer (MZI)-synchronized AWG with reagrd to reduced loss, and athermalization. The paper then reports our recent demonstration of the integration of a PLC-based wavelength selective switch (WSS) and an integrated single-chip VMUX/DEMUX.

  4. Planar metal-dielectric waveguides with the expanded singlemode band regime

    Directory of Open Access Journals (Sweden)

    V. G. Levandovskyy

    2012-12-01

    Full Text Available Purpose. Present work is devoted to the optimization of metal-dielectric waveguides for practical application in integrated optics. Actuality and practical importance. Such waveguides are a perspective element for creation of variety devices of integrated optics (multichannel splitters, modulators and switches, the filters radiating structures etc. in various units of integral-optical schemes. Choosing of method. It is shown, that optimization of parameters of planar metal-dielectric waveguide can be performed using the values of phase and group velocities of propagating modes on fixed frequency when solving the return scattering problem on the basis of wave equations. Conclusion. The method of return scattering problem solving that consists in restoration of differential operator from its spectral function make it possible to receive singlemode thin-film metal-dielectric waveguides having the expanded singlemode band regime and the increased cross-section sizes. For verification of results the model experiment with solving of direct problem for obtaining waveguides is executed.

  5. Theory of a curved planar waveguide with Robin boundary conditions

    Science.gov (United States)

    Olendski, O.; Mikhailovska, L.

    2010-03-01

    A model of a thin straight strip with a uniformly curved section and with boundary requirements zeroing at the edges a linear superposition of the wave function and its normal derivative (Robin boundary condition) is analyzed theoretically within the framework of the linear Schrödinger equation and is applied to the study of the processes in the bent magnetic multilayers, superconducting films and metallic ferrite-filled waveguides. In particular, subband thresholds of the straight and curved parts of the film are calculated and analyzed as a function of the Robin parameter 1/Λ , with Λ being an extrapolation length entering Robin boundary condition. For the arbitrary Robin coefficients which are equal on the opposite interfaces of the strip and for all bend parameters the lowest-mode energy of the continuously curved duct is always smaller than its straight counterpart. Accordingly, the bound state below the fundamental propagation threshold of the straight arms always exists as a result of the bend. In terms of the superconductivity language it means an increased critical temperature of the curved film compared to its straight counterpart. Localized-level dependence on the parameters of the curve is investigated with its energy decreasing with increasing bend angle and decreasing bend radius. Conditions of the bound-state existence for the different Robin parameters on the opposite edges are analyzed too; in particular, it is shown that the bound state below the first transverse threshold of the straight arm always exists if the inner extrapolation length is not larger than the outer one. In the opposite case there is a range of the bend parameters where the curved film cannot trap the wave and form the localized mode; for example, for the fixed bend radius the bound state emerges from the continuum at some nonzero bend angle that depends on the difference of the two lengths Λ at the opposite interfaces. Various transport properties of the film such as

  6. Optically pumped planar waveguide lasers: Part II: Gain media, laser systems, and applications

    Science.gov (United States)

    Grivas, Christos

    2016-01-01

    The field of optically pumped planar waveguide lasers has seen a rapid development over the last two decades driven by the requirements of a range of applications. This sustained research effort has led to the demonstration of a large variety of miniature highly efficient laser sources by combining different gain media and resonator geometries. One of the most attractive features of waveguide lasers is the broad range of regimes that they can operate, spanning from continuous wave and single frequency through to the generation of femtosecond pulses. Furthermore, their technology has experienced considerable advances to provide increased output power levels, deriving benefits from the relative immunity from the heat generated in the gain medium during laser operation and the use of cladding-pumped architectures. This second part of the review on optically pumped planar waveguide lasers provides a snapshot of the state-of-the-art research in this field in terms of gain materials, laser system designs, and as well as a perspective on the status of their application as real devices in various research areas.

  7. Influence of parameters on light propagation dynamics in optically induced planar waveguide arrays

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The diffraction and refraction of light beam in optical periodic structures can be determined by the photonic band-gap structures of spatial frequency.In this paper,by employing the equation governing the nonlinear light propagations in photorefractive crystals,we study the photonic band-gap structures, Bloch modes,and light transmission properties of optically induced planar waveguide arrays.The relationship between the photonic band-gap structures and the light diffraction characteristics is discussed in detail.Then the influence of the parameters of planar waveguide arrays on the band-gaps structures,Bloch modes,and linear light transmissions is analyzed.It is revealed that the linear light transmission properties of waveguide arrays are tightly related to the diffraction relationships determined by band-gap structures.And the Bloch modes corresponding to different transmission bands can be excited by different excitation schemes.Both the increases of the intensity and the period of the array writing beam will lead to the broadening of the forbidden gaps and the concentration of the energy of the Bloch modes to the high-index regions.Furthermore,the broadening of the forbidden gaps will lead to separation and transition between the Bloch modes of neighboring bands around the Bragg angle.Additionally,with the increase of the intensity of the array writing beams,the influences from light intensity will tend to be steady due to the saturation of the photorefractive effect.

  8. Influence of parameters on light propagation dynamics in optically induced planar waveguide arrays

    Institute of Scientific and Technical Information of China (English)

    LIU Sheng; ZHANG Peng; XIAO FaJun; YANG DeXing; ZHAO JianLin

    2009-01-01

    The diffraction and refraction of light beam in optical periodic structures can be determined by the photonic band-gap structures of spatial frequency. In this paper, by employing the equation governing the nonlinear light propagations in photorefractive crystals, we study the photonic band-gap structures,Bloch modes, and light transmission properties of optically induced planar waveguide arrays. The relationship between the photonic band-gap structures and the light diffraction characteristics is discussed in detail. Then the influence of the parameters of planar waveguide arrays on the band-gaps structures, Bloch modes, and linear light transmissions is analyzed. It is revealed that the linear light transmission properties of waveguide arrays are tightly related to the diffraction relationships determined by band-gap structures. And the Bloch modes corresponding to different transmission bands can be excited by different excitation schemes. Both the increases of the intensity and the period of the array writing beam will lead to the broadening of the forbidden gaps and the concentration of the energy of the Bloch modes to the high-index regions. Furthermore, the broadening of the forbidden gaps will lead to separation and transition between the Bloch modes of neighboring bands around the Bragg angle. Additionally, with the increase of the intensity of the array writing beams, the influences from light intensity will tend to be steady due to the saturation of the photorefractive effect.

  9. Optical planar waveguide in sodium-doped calcium barium niobate crystals by carbon ion implantation

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Jin-Hua, E-mail: zhaojinhuazjh@gmail.com [School of Science, Shandong Jianzhu University, Jinan 250101 (China); Qin, Xi-Feng; Wang, Feng-Xiang; Fu, Gang; Wang, Hui-Lin [School of Science, Shandong Jianzhu University, Jinan 250101 (China); Wang, Xue-Lin [School of Physics, Key Laboratory of Particle Physics and Particle Irradiation, Ministry of Education, and State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100 (China)

    2013-07-15

    There is great interest in niobate crystals which belong to the tetragonal tungsten bronze (TTB) families owing to their intriguing properties. As one representative of such crystals, CBN (calcium barium niobate) has attracted rapidly growing attention. Because it has a higher Curie temperature than SBN (strontium barium niobate), possesses outstanding ferroelectric and it possesses optical properties. In addition, doped with sodium, CBN will show a higher Curie temperature than pure CBN. We report on the fabrication and characterization of optical planar waveguide in x-cut sodium-doped calcium barium niobate crystal by using C ion implantation. The guided-mode properties at the wavelength of 633 and 1539 nm are investigated through prism-coupling measurements, respectively. By applying direct end-face coupling arrangement, the near-field optical intensity distribution of waveguide modes is measured at 633 nm. For comparison, the modal profile of the same guided mode is also numerically calculated by the finite difference beam-propagation method via computer software BeamPROP. The transmission spectra of the waveguide before and after ion implantation treatments were investigated also. Our experiment results reveal that the waveguide could propagate light with transverse magnetic polarized direction only and it is assumed that the polarization selectivity of CBN crystal may responsible for this phenomenon.

  10. Back-reflecting interferometeric sensor based on grating coupler on a planar waveguide

    CERN Document Server

    Demeter, Anat

    2015-01-01

    We present a one-port sensor based on a single diffraction grating delineated over a planar optical waveguide. Distinctly to previously reported devices, the grating here is used not only as I/O coupler, but also provides a built-in reference beam which is basically unaffected by the sensing process as manifested in changes of the effective refractive index of the waveguide. The sensing process causes two effects simultaneously: a change in the angle of the out-coupled beam and a change in the phase accumulated by that beam. Both changes can be determined by their conjunction with the reference beam back-diffracted directly by the grating. These two effects are expected to have despair sensitivities, the angle changing effect being coarse and the interferometric phase-change effect being highly sensitive. Sensing simultaneously at two different scales will translate into a large sensing dynamic range.

  11. A Compact, Planar, Eight-Port Waveguide Power Divider\\/Combiner The Cross Potent Superhybrid

    CERN Document Server

    Nantista, C D; Nantista, Christopher D.; Tantawi, Sami G.

    2000-01-01

    In this letter, we present a novel four-way divider/combiner in rectangular waveguide. The design is completely two-dimensional in the h-plane, with eight-fold mirror symmetry, and is based on a recent four-port hybrid design [6]. In combining mode, it can function as a phased array with four inputs and four outputs. The planar nature of this design provides advantages, such as the freedom to increase the waveguide height beyond the over-moding limit in order to reduce field strengths. Along with its open geometry, this makes it ideal for high-power applications where rf break down is a concern. Design criteria, field-solver simulation results, and prototype measurements are presented.

  12. Single-strand DNA detection using a planar photonic-crystal-waveguide-based sensor.

    Science.gov (United States)

    Toccafondo, V; García-Rupérez, J; Bañuls, M J; Griol, A; Castelló, J G; Peransi-Llopis, S; Maquieira, A

    2010-11-01

    We report an experimental demonstration of single-strand DNA (ssDNA) detection at room temperature using a photonic-crystal-waveguide-based optical sensor. The sensor surface was previously biofunctionalized with ssDNA probes to be used as specific target receptors. Our experiments showed that it is possible to detect these hybridization events using planar photonic-crystal structures, reaching an estimated detection limit as low as 19.8 nM for the detection of the complementary DNA strand.

  13. A 60 GHz Planar Diplexer Based on Substrate Integrated Waveguide Technology

    Directory of Open Access Journals (Sweden)

    Nikolaos Athanasopoulos

    2013-01-01

    Full Text Available This paper presents a millimeter-wave, 60 GHz frequency band planar diplexer based on substrate integrated waveguide (SIW technology. Diplexer consists of a pair of 5th-order SIW bandpass channel filters with center frequencies at 59.8 GHz and 62.2 GHz providing 1.67% and 1.6% relative bandwidths, respectively. SIW-to-microstrip transitions at diplexer ports enable integration in a millimeter-wave transceiver front end. Measurements are in good agreement with electromagnetic simulation, reporting very good channel isolation, small return losses, and moderate insertion losses in the passbands. The proposed SIW planar diplexer is integrated into a millimeter-wave transceiver front end for 60 GHz point-to-point multigigabit wireless backhaul applications, providing high isolation between transmit and receive channels.

  14. Tape casting fabrication and properties of planar waveguide YAG/Yb:YAG/YAG transparent ceramics

    Science.gov (United States)

    Zhao, Yu; Liu, Qiang; Ge, Lin; Wang, Chao; Li, Wenxue; Yang, Chao; Wang, Juntao; Yuan, Lei; Xie, Tengfei; Kou, Huamin; Pan, Yubai; Gao, Qingsong; Bo, Yong; Peng, Qinjun; Xu, Zuyan; Li, Jiang

    2017-07-01

    Highly transparent YAG/10at.%Yb:YAG/YAG planar waveguide ceramics were fabricated by the non-aqueous tape casting and solid-state reactive sintering technology. The tapes are relatively homogeneous and the green body shows a dense structure without distinct interfaces after the treatment of debinding and cold isostatic pressing. YAG/10at.%Yb:YAG/YAG ceramics with almost full dense structure were obtained by vacuum-sintering at 1760 °C for 30 h. For the mirror-polished sample with the thickness of 3.5 mm, the In-line transmittance was measured to be 83.6% at the visual wavelength of 400 nm. The diffusion distance of the Yb3+ ions was about 215 μm along the thickness direction of the ceramics. In the lasing experiments, the YAG/10at.%Yb:YAG/YAG planar waveguide ceramics were end-pumped by a 976 nm semiconductor diode laser and enabled efficient continuous-wave lasers, which resulted in a maximum output power of 1.6 W and a slope efficiency of 34.4% at 1030 nm.

  15. Analytical solutions for optical forces between two dielectric planar waveguides immersed in dielectric fluid media

    CERN Document Server

    Rodrigues, Janderson Rocha

    2016-01-01

    We investigate optical (transverse gradient) forces between two high-index dielectric planar waveguides immersed in low-index dielectric fluid media. Complimentary to previous studies, we extend optical forces calculations, in order to take into account a non-vacuum (and non-air) background medium, by using the Minkowski stress tensor formulation; we derived a very simple set of equations in terms of the effective refractive indexes of the waveguide eigenmodes. We also used a normalized version of the dispersion relation method to calculate the optical forces, in order to validate our results for different dielectric fluid media. Excellent agreement between the two methods was obtained for all analyzed cases. We show that, due to slot-waveguide effect, the TM modes are more sensitive to changes in the fluid refractive index than the TE ones. Furthermore, the repulsive optical force of the antisymmetric TM1 mode becomes stronger for higher refractive indexes, whereas the attractive force of the symmetric TM0 m...

  16. Resonant scattering and mode coupling in two-dimensional textured planar waveguides.

    Science.gov (United States)

    Cowan, A R; Paddon, P; Pacradouni, V; Young, J F

    2001-05-01

    A heuristic formalism is developed for efficiently determining the specular reflectivity spectrum of two-dimensionally textured planar waveguides. The formalism is based on a Green's function approach wherein the electric fields are assumed to vary little over the thickness of the textured part of the waveguide. Its accuracy, when the thickness of the textured region is much smaller than the wavelength of relevant radiation, is verified by comparison with a much less efficient, exact finite difference solution of Maxwell's equations. In addition to its numerical efficiency, the formalism provides an intuitive explanation of Fano-like features evident in the specular reflectivity spectrum when the incident radiation is phase matched to excite leaky electromagnetic modes attached to the waveguide. By associating various Fourier components of the scattered field with bare slab modes, the dispersion, unique polarization properties, and lifetimes of these Fano-like features are explained in terms of photonic eigenmodes that reveal the renormalization of the slab modes due to interaction with the two-dimensional grating. An application of the formalism, in the analysis of polarization-insensitive notch filters, is also discussed.

  17. Toward photostable multiplex analyte detection on a single mode planar optical waveguide

    Energy Technology Data Exchange (ETDEWEB)

    Mukundan, Harshini [Los Alamos National Laboratory; Xei, Hongshi [Los Alamos National Laboratory; Anderson, Aaron S [Los Alamos National Laboratory; Grace, Wynne K [Los Alamos National Laboratory; Martinez, Jennifer S [NON LANL; Swanson, Basil [Los Alamos National Laboratory

    2009-01-01

    We have developed a waveguide-based optical biosensor for the sensitive and specific detection of biomarkers associated with disease. Our technology combines the superior optical properties of single-mode planar waveguides, the robust nature of functionalized self-assembled monolayer sensing films and the specificity of fluorescence sandwich immunoassays to detect biomarkers in complex biological samples such as serum, urine and sputum. We have previously reported the adaptation of our technology to the detection of biomarkers associated with breast cancer and anthrax. However, these approaches primarily used phospholipid bilayers as the functional film and organic dyes (ex: AlexaFluors) as the fluorescence reporter. Organic dyes are easily photodegraded and are not amenable to multiplexing because of their narrow Stokes' shift. Here we have developed strategies for conjugation of the detector antibodies with quantum dots for use in a multiplex detection platform. We have previously evaluated dihydroxylipoic acid quantum dots for the detection of a breast cancer biomarker. In this manuscript, we investigate the detection of the Bacillus anthracis protective antigen using antibodies conjugated with polymer-coated quantum dots. Kinetics of binding on the waveguide-based biosensor is reported. We compare the sensitivity of quantum dot labeled antibodies to those labeled with AlexaFluor and demonstrate the photostability of the former in our assay platform. In addition, we compare sulfydryl labeling of the antibody in the hinge region to that of nonspecific amine labeling. This is but the first step in developing a multiplex assay for such biomarkers on our waveguide platform.

  18. Femtosecond pulse generation at 50 W average powers from an Yb:KYW-Yb:YAG planar-waveguide MOPA

    Directory of Open Access Journals (Sweden)

    Baker H. J.

    2013-03-01

    Full Text Available An Yb:YAG planar-waveguide power amplifier seeded by an Yb:KYW master oscillator is reported. The system produced 700-fs pulses at 1032 nm at average output powers of 50 W and a frequency of 53 MHz.

  19. Propagation of TE and TM polarised light through smoothed sixty degree bends in planar photonic crystal waveguides

    DEFF Research Database (Denmark)

    Frandsen, Lars Hagedorn; Borel, Peter Ingo; Thorhauge, Morten;

    2003-01-01

    In this paper, bends in planar PCWs are investigated by introducing two smoothed 60° bends each having one hole. The PCWs are defined by leaving out single rows of holes. In and out coupling of light to the PCWs is obtained utilising tapered ridge waveguides. Transmission spectra are recorded...

  20. Erbium-activated silica-zirconia planar waveguides prepared by sol-gel route

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, Rogeria R. [Departamento de Quimica, Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo-Av., Bandeirantes 3900, cep 14040-901, Ribeirao Preto-SP (Brazil)], E-mail: rrgoncalves@ffclrp.usp.br; Messaddeq, Younes [Instituto de Quimica, UNESP-Rua Prof. Francisco Degni, s/n, Quitandinha, cep 14800-900 Araraquara-SP (Brazil); Chiasera, Alessandro; Jestin, Yoann; Ferrari, Maurizio [CNR-IFN, Istituto di Fotonica e Nanotecnologie, CSMFO group, via Sommarive 14, 38050 Povo, Trento (Italy); Ribeiro, Sidney J.L. [Instituto de Quimica, UNESP-Rua Prof. Francisco Degni, s/n, Quitandinha, cep 14800-900 Araraquara-SP (Brazil)

    2008-03-31

    Er{sup 3+} doped (100 - x)SiO{sub 2} - xZrO{sub 2} planar waveguides were prepared by the sol-gel route, with x ranging from 10 up to 30 mol%. Multilayer films doped with 0.3 mol% Er{sup 3+} ions were deposited on fused quartz substrates by the dip-coating technique. The thickness and refractive index were measured by m-line spectroscopy at different wavelengths. The fabrication protocol was optimized in order to confine one propagating mode at 1.5 {mu}m. Photoluminescence in the near and visible region indicated a crystalline local environment for the Er{sup 3+} ion.

  1. Optical sampling of ultrahigh bitrate signals using highly nonlinear chalcogenide planar waveguides or tapered fibers

    Science.gov (United States)

    Van Erps, Jürgen; Luan, Feng; Pelusi, Mark D.; Mägi, Eric; Iredale, Tim; Madden, Steve; Choi, Duk Yong; Bulla, Douglas A.; Luther-Davies, Barry; Thienpont, Hugo; Eggleton, Benjamin J.

    2010-06-01

    As the bit rates of optical networks increase, the ability of accurate monitoring of optical waveforms has become increasingly important. In recent years, optical sampling has emerged as a technique to perform time-resolved measurements of optical data signals at high data rates with a bandwidth that cannot be reached by conventional photodetectors and oscilloscopes. In an optical sampling system, the optical signal is sampled in the optical domain by a nonlinear optical sampling gate before the resulting samples are converted to an electrical signal. This avoids the need for high bandwidth electronics if the optical sampling gate is operated with a modest repetition frequency. In this paper, we present an optical sampling system using the optical Kerr effect in a highly nonlinear chalcogenide device, enabling combined capability for femtosecond resolution and broadband signal wavelength tunability. A temporal resolution 450-fs is achieved using four-wave mixing (FWM) in dispersion-engineered chalcogenide waveguides: on one hand a 7-cm long planar waveguide (integrated on a photonic chip) and on the other hand a 5-cm long tapered fiber. The use of a short length, dispersion-shifted waveguide with ultrahigh nonlinearity (10000/W/km) enables high-resolution optical sampling without the detrimental effect of chromatic dispersion on the temporal distortion of the signal and sampling pulses, as well as their phase mismatch (which in turn would degrade the FWM efficiency and the sensitivity of the measurement). Using these chalcogenide devices, we successfully monitor a 640-Gb/s optical time-division multiplexing (OTDM) datastream, showcasing its potential for monitoring of signals at bitrates approaching and beyond Tb/s. We compare the advantages and disadvantages of both approaches and discuss fundamental limitations as well as potential improvements.

  2. Sub-wavelength grating structure on the planar waveguide (Conference Presentation)

    Science.gov (United States)

    Qing-Song, Zhu; Sheng-Hui, Chen

    2016-10-01

    Making progress in recent years, with the technology of the grating, the grating period can be reduced to shrink the size of the light coupler on a waveguide. The working wavelength of the light coupler can be in the range from the near-infrared to visible. In this study , we used E-gun evaporation system with ion-beam-assisted deposition system to fabricate bottom cladding (SiO2), guiding layer (Ta2O5) and Distributed Bragg Reflector(DBR) of the waveguide on the silicon substrate. Electron-beam lithography is used to make sub-wavelength gratings and reflector grating on the planar waveguide which is a coupling device on the guiding layer. The best fabrication parameters were analyzed to deposit the film. The exposure and development times also influenced to fabricate the grating quality. The purpose is to reduce the device size and enhance coupling efficiency which maintain normal incidence of the light . We designed and developed the device using the Finite-Difference Time-Domain (FDTD) method. The grating period, depth, fill factor, film thickness, Distributed Bragg Reflector(DBR) numbers and reflector grating period have been discussed to enhance coupling efficiency and maintained normal incidence of the light. According to the simulation results, when the wavelength is 1300 nm, the coupling grating period is 720 nm and the Ta2O5 film is 460 nm with 360 nm of reflector grating period and 2 layers of Distributed Bragg Reflector, which had the optimum coupling efficiency and normal incidence angle. In the measurement, We successfully measured the TE wave coupling efficiency of the photoresist grating coupling device.

  3. Planar waveguides formed in a new chemically stable Er3+/Yb3+ co-doped phosphate glass

    Institute of Scientific and Technical Information of China (English)

    Shilong Zhao; Baoyu Chen; Junjiang Hu; Lili Hu

    2005-01-01

    @@ A new Er3+/Yb3+ co-doped phosphate glass has been prepared, which exhibits good chemical durability and spectral properties. Planar graded index waveguides have been fabricated in the glass by Ag+-Na+ ion exchange in a mixed melt of silver nitrate and potassium nitrate. Ion exchange is carried out by varying the process parameters such as temperature, diffusion time, and molten salt compositions. The diffusion parameters, diffusion coefficients, and activation energy are determined by the guidelines of fabricated waveguides, which are determined by the input prism coupling technique.

  4. Arrayed Waveguide Gratings and Their Application Using Super-High-Δ Silica-Based Planar Lightwave Circuit Technology

    Science.gov (United States)

    Maru, Koichi; Uetsuka, Hisato

    This paper reviews our recent progress on arrayed waveguide gratings (AWGs) using super-high-Δ silica-based planar lightwave circuit (PLC) technology and their application to integrated optical devices. Factors affecting the chip size of AWGs and the impact of increasing relative index difference Δ on the chip size are investigated, and the fabrication result of a compact athermal AWG using 2.5%-Δ silica-based waveguides is presented. As an application of super-high-Δ AWGs to integrated devices, a flat-passband multi/demultiplexer consisting of an AWG and cascaded MZIs is presented.

  5. Visible to near-infrared supercontinuum generation in yttrium orthosilicate bulk crystal and ion implanted planar waveguide.

    Science.gov (United States)

    Xiang, Bingxi; Ren, Xikui; Ruan, Shuangchen; Wang, Lei; Yan, Peiguang; Han, Huangpu; Wang, Meng; Yin, Jinde

    2016-08-16

    This paper reports on the supercontinuum generation in yttrium orthosilicate bulk crystal and 6-mm-long ion implanted planar waveguide. The waveguide is fabricated by 6 MeV oxygen ions implantation with fluence of 5 × 10(14) ions/cm(2) at room temperature. The yttrium orthosilicate bulk crystal and waveguide are pumped using a mode-locked Ti:Sapphire laser with a center wavelength of 800 nm. The generated broadest supercontinuum spans 720 nm (at -30 dB points) from 380 to 1100 nm in bulk crystal and 510 nm (at -30 dB points) from 490 to 1000 nm in ion implanted waveguide, respectively. Compared to the bulk crystal, the ion implanted waveguide requires almost three orders of magnitude lower pump power to achieve a similar level of broadening. The supercontinuum is generated in the normal dispersion regime and exhibits a relatively smooth spectral shape. Our research findings indicate that ion implantation is an efficient method to produce waveguide in yttrium orthosilicate crystal for low-threshold supercontinuum generation.

  6. Visible to near-infrared supercontinuum generation in yttrium orthosilicate bulk crystal and ion implanted planar waveguide

    Science.gov (United States)

    Xiang, Bingxi; Ren, Xikui; Ruan, Shuangchen; Wang, Lei; Yan, Peiguang; Han, Huangpu; Wang, Meng; Yin, Jinde

    2016-08-01

    This paper reports on the supercontinuum generation in yttrium orthosilicate bulk crystal and 6-mm-long ion implanted planar waveguide. The waveguide is fabricated by 6 MeV oxygen ions implantation with fluence of 5 × 1014 ions/cm2 at room temperature. The yttrium orthosilicate bulk crystal and waveguide are pumped using a mode-locked Ti:Sapphire laser with a center wavelength of 800 nm. The generated broadest supercontinuum spans 720 nm (at ‑30 dB points) from 380 to 1100 nm in bulk crystal and 510 nm (at ‑30 dB points) from 490 to 1000 nm in ion implanted waveguide, respectively. Compared to the bulk crystal, the ion implanted waveguide requires almost three orders of magnitude lower pump power to achieve a similar level of broadening. The supercontinuum is generated in the normal dispersion regime and exhibits a relatively smooth spectral shape. Our research findings indicate that ion implantation is an efficient method to produce waveguide in yttrium orthosilicate crystal for low-threshold supercontinuum generation.

  7. Bandpass filters based on planar metal-dielectric structures in the E-plane of a rectangular waveguide (Review)

    Science.gov (United States)

    Gololobov, V. P.; Omelianenko, M. Iu.

    1987-01-01

    The paper surveys the literature and some original results on the development of low-insertion-loss E-plane filters for microwave integrated circuits. Emphasis is placed on the design and fabrication of inductive-strip bandpass filters in rectangular and partially filled waveguides. The possibility of improving the performance of these filters in the multilayer planar realization is demonstrated theoretically. Experimental results agree satisfactorily with calculations.

  8. Demonstration of a micromachined planar distribution network in gap waveguide technology for a linear slot array antenna at 100 GHz

    Science.gov (United States)

    Rahiminejad, S.; Zaman, A. U.; Haasl, S.; Kildal, P.-S.; Enoksson, P.

    2016-07-01

    The need for high frequency antennas is rapidly increasing with the development of new wireless rate communication technology. Planar antennas have an attractive form factor, but they require a distribution network. Microstrip technology is most commonly used at low frequency but suffers from large dielectric and ohmic losses at higher frequencies and particularly above 100 GHz. Substrate-integrated waveguides also suffer from dielectric losses. In addition, standard rectangular waveguide interfaces are inconvenient due to the four flange screws that must be tightly fastened to the antenna to avoid leakage. The current paper presents a planar slot array antenna that does not suffer from any of these problems. The distribution network is realized by micromachining using low-loss gap waveguide technology, and it can be connected to a standard rectangular waveguide flange without using any screws or additional packaging. To realize the antenna at these frequencies, it was fabricated with micromachining, which offers the required high precision, and a low-cost fabrication method. The antenna was micromachined with DRIE in two parts, one silicon-on-insulator plate and one Si plate, which were both covered with Au to achieve conductivity. The input reflection coefficient was measured to be below 10 dB over a 15.5% bandwidth, and the antenna gain was measured to be 10.4 dBi, both of which are in agreement with simulations.

  9. Planar architecture for microstrip interfaced packaging of coplanar-waveguide-based radio frequency microelectromechanical system switches

    Science.gov (United States)

    Singh, Shailendra; Giridhar, Malalahalli Sreenivasamurthy; Rao, Cheemalamarri Venkata Narasimha; Bhalke, Sangam; Islam, Rifqul

    2015-01-01

    This paper describes the architecture of microstrip (MS) interfaced packaging of a coplanar-waveguide (CPW)-based radio frequency microelectromechanical systems (RF MEMS) switch in a hermetic metal-ceramic RF package. The switch is integrated along with CPW to MS (CPW-MS) transitions within the package itself. This makes the MS interfaced packaged switch module readily mountable on MS based RF boards and subsystems. The CPW-MS transition for the package was designed as a separate off-chip entity on an alumina substrate and utilizes via hole. The integrated three-dimensional model of the package consisting of the RF MEMS switch and the transitions was simulated using high frequency structure simulator. The realized module shows an insertion loss of 0.2 and 1.1 dB at 100 MHz and 7 GHz, respectively. The measured isolation is better than 60 dB at 100 MHz and 30 dB at 7 GHz. The return loss is better than 15 dB up to 7 GHz. The estimated packaging and transitioning loss is 0.5 dB at 5 GHz. This packaging architecture is a planar solution for the MS interfaced packaging of CPW based RF MEMS switches for designers who do not have access to high-end technologies, such as zero-level packaging, through silicon via or low temperature co-fired ceramics.

  10. Directly UV written silica-on-silicon planar waveguides with low insertion loss

    DEFF Research Database (Denmark)

    Zauner, Dan; Svalgaard, Mikael; Kristensen, Martin

    1998-01-01

    in waveguide geometry, and excellent control of the refractive index step. Direct UV writing of waveguides became a realistic alternative to other fabrication methods when propagation losses below 0.2 dB/cm were reported in single-mode waveguides. However, the coupling loss to optical fibers remained high...

  11. Analysis and Determination of Refractive Index Profiles of O2+ Ion-Implanted LiNbO3 Planar Waveguide Using Etching and Ellipsometry Techniques

    Institute of Scientific and Technical Information of China (English)

    LIU Han-Ping; MA Xue-Jian; LU Fei; WANG Xue-Lin; YANG Tian-Lin; LV Ying-Bo; LI Yan-Hui; LIU Xiang-Zhi; ZHANG Rui-Feng; SONG Qiang

    2008-01-01

    The refractive index profiles of 3 MeV O2+ion-implanted planar waveguides in lithium niobate are reconstructed based on etching and ellipsometry techniques.SRIM2003 code is used to simulate the damage distribution in waveguide.It is demonstrated that the index profile of this kind of waveguide,extending to several micrometres in depth,can be determined by etching in combination with following ellipsometric measurements.A good agreement is found between the simulated damage distributions in waveguide and the index profiles based on experimental data,and the width of refractive index barrier is wider than the result of SRIM2003.

  12. Planar optical waveguide based sandwich assay sensors and processes for the detection of biological targets including early detection of cancers

    Science.gov (United States)

    Martinez, Jennifer S.; Swanson, Basil I.; Shively, John E.; Li, Lin

    2009-06-02

    An assay element is described including recognition ligands adapted for binding to carcinoembryonic antigen (CEA) bound to a film on a single mode planar optical waveguide, the film from the group of a membrane, a polymerized bilayer membrane, and a self-assembled monolayer containing polyethylene glycol or polypropylene glycol groups therein and an assay process for detecting the presence of CEA is described including injecting a possible CEA-containing sample into a sensor cell including the assay element, maintaining the sample within the sensor cell for time sufficient for binding to occur between CEA present within the sample and the recognition ligands, injecting a solution including a reporter ligand into the sensor cell; and, interrogating the sample within the sensor cell with excitation light from the waveguide, the excitation light provided by an evanescent field of the single mode penetrating into the biological target-containing sample to a distance of less than about 200 nanometers from the waveguide thereby exciting any bound reporter ligand within a distance of less than about 200 nanometers from the waveguide and resulting in a detectable signal.

  13. Measurement of the modal birefringence of single-mode K(+) ion-exchanged planar waveguides with polarimetric interferometry.

    Science.gov (United States)

    Qi, Z M; Itoh, K; Murabayashi, M

    2000-11-01

    The polarimetric interference pattern on the surface of single-mode planar waveguides made by potassium ion exchange in soda-lime glass substrates can be observed through a 45 degrees analyzer, which allows for the high-precision measurement of the modal birefringence of samples in a wide range of 0 to 5 x 10(-4). Using this method, believed to be new, we investigated the effects of exchange temperature and time on the modal birefringence of single-mode potassium ion-exchanged waveguides. The modal birefringence profile was achieved by measurement of the variation of the phase difference between the TE(0) and the TM(0) modes with hydrofluoric-acid-etching depth of the sample.

  14. Planar-waveguide external cavity laser stabilization for an optical link with 10(-19) frequency stability.

    Science.gov (United States)

    Clivati, Cecilia; Mura, Alberto; Calonico, Davide; Levi, Filippo; Costanzo, Giovanni A; Calosso, Claudio E; Godone, Aldo

    2011-12-01

    We stabilized the frequency of a compact planar-waveguide external cavity laser (ECL) on a Fabry-Perot cavity (FPC) through a Pound-Drever-Hall scheme. The residual frequency stability of the ECL is 10(-14), comparable to the stability achievable with a fiber laser (FL) locked to an FPC through the same scheme. We set up an optical link of 100 km, based on fiber spools, that reaches 10(-19) relative stability, and we show that its performances using the ECL or FL are comparable. Thus ECLs could serve as an excellent replacement for FLs in optical links where cost-effectiveness and robustness are important considerations.

  15. High precision planar waveguide propagation loss measurement technique using a Fabry-Perot cavity

    DEFF Research Database (Denmark)

    Feuchter, Thomas; Thirstrup, Carsten

    1994-01-01

    A high precision measurement technique for characterizing the propagation loss in silica low-loss optical waveguides, based on measuring the contrast of a Fabry-Perot cavity, is demonstrated. The cavity consists of the waveguide coupled to two polarization-maintaining fibers, each end facet coated...

  16. Large Core Planar 1 x 2 Optical Power Splitter with Acrylate and Epoxy Resin Waveguides on Polydimetylsiloxane Substrate

    Directory of Open Access Journals (Sweden)

    V. Prajzler

    2014-04-01

    Full Text Available Fabrication process of multimode 1x2 optical rectangular planar power splitter suitable for low-cost short distance optical network is presented. The splitters were designed by beam propagation method for standard input/output plastic optical fibre. Materials used for the splitter were: UV acrylate photopolymer polymer or epoxy resin for optical core waveguide layers and Y-groove substrate for the core layer was poly(methyl methacrylate or polydimetylsiloxane made by replication process on poly(methyl methacrylate pattern. The insertion losses of 1x2 splitters with acrylate waveguide layers were around 2.7 dB at 532 nm and 4.1 dB at 650 nm and those for epoxy resin waveguide layer were around 3.7 dB at 850 nm. The 1x2 splitters were tested by signal transmission being connected to the internet network by using optoelectronic switches and we achieved the maximum possible transmission data rate as provided by the computer network.

  17. Formation of a planar optical waveguide by mega-electron-volt He+ and P+ ions implanted in a BiB(3)O(6) crystal.

    Science.gov (United States)

    Chen, F; Hu, H; Wang, K M; Teng, B; Wang, J Y; Lu, Q M; Shen, D Y

    2001-12-15

    What is believed to be the first planar optical waveguide was formed in BiB(3)O(6) (BIBO) crystal by 2.8-MeV He(+)-ion implantation with a dose of 2x10(16)ions/cm (2) and 2.8-MeV P(+)-ion implantation with a dose of 1x10(14)ions/cm (2) at room temperature. We observed 21 darks modes for the He(+)-ion-implanted BIBO waveguides and four dark modes for the P(+)-ion-implanted waveguides. The refractive-index profile of the He(+)-implanted BIBO waveguide was analyzed. The data also suggest that the BIBO waveguides formed by MeV He(+)-ion and P(+)-ion implantation differ in their developing mechanisms.

  18. Densification behavior, doping profile and planar waveguide laser performance of the tape casting YAG/Nd:YAG/YAG ceramics

    Science.gov (United States)

    Ge, Lin; Li, Jiang; Qu, Haiyun; Wang, Juntao; Liu, Jiao; Dai, Jiawei; Zhou, Zhiwei; Liu, Binglong; Kou, Huamin; Shi, Yun; Wang, Zheng; Pan, Yubai; Gao, Qingsong; Guo, Jingkun

    2016-10-01

    The sintering behavior and doping concentration profile of the planar waveguide YAG/Nd:YAG/YAG ceramics by the tape casting and solid-state reaction method were investigated on the basis of densification trajectory, microstructure evolution, and Nd3+ ions diffusion. The porosity of the green body by tape casting and cold isostatic pressing is about 38.6%. And the green bodies were consolidated from 1100 °C to 1800 °C for 0.5-20 h to study the densification and the doping diffusion behaviors. At the temperature higher than 1500 °C, pure YAG phase is formed, followed by the densification and grain growth process. With the increase of temperature, two sintering stages occur, corresponding to remarkable densification and significant grain growth, respectively. The mechanism controlling densification at 1550 °C is grain boundary diffusion. The diffusion of Nd3+ ions is more sensitive to temperature than the sintering time, and the minimum temperature required for the obvious diffusion of Nd3+ ions is higher than 1700 °C. Finally, planar waveguide YAG/1.5 at.%Nd:YAG/YAG transparent ceramics with in-line transmittance of 84.8% at 1064 nm were obtained by vacuum-sintering at 1780 °C for 30 h. The fluorescence lifetime of 4F3/2 state of Nd3+ in the specimen is about 259 μs. The prepared ceramic waveguide was tested in a laser amplifier and the laser pulse was amplificated from 87 mJ to 238 mJ, with the pump energy of 680 mJ.

  19. Development and validation of an ultrasensitive fluorescence planar waveguide biosensor for the detection of paralytic shellfish toxins in marine algae.

    Science.gov (United States)

    Meneely, Julie P; Campbell, Katrina; Greef, Charles; Lochhead, Michael J; Elliott, Christopher T

    2013-03-15

    Marine dinoflagellates of the genera Alexandrium are well known producers of the potent neurotoxic paralytic shellfish toxins that can enter the food web and ultimately present a serious risk to public health in addition to causing huge economic losses. Direct coastal monitoring of Alexandrium spp. can provide early warning of potential shellfish contamination and risks to consumers and so a rapid, sensitive, portable and easy-to-use assay has been developed for this purpose using an innovative planar waveguide device. The disposable planar waveguide is comprised of a transparent substrate onto which an array of toxin-protein conjugates is deposited, assembled in a cartridge allowing the introduction of sample, and detection reagents. The competitive assay format uses a high affinity antibody to paralytic shellfish toxins with a detection signal generated via a fluorescently labelled secondary antibody. The waveguide cartridge is analysed by a simple reader device and results are displayed on a laptop computer. Assay speed has been optimised to enable measurement within 15 min. A rapid, portable sample preparation technique was developed for Alexandrium spp. in seawater to ensure analysis was completed within a short period of time. The assay was validated and the LOD and CCβ were determined as 12 pg/mL and 20 pg/mL respectively with an intra-assay CV of 11.3% at the CCβ and an average recovery of 106%. The highly innovative assay was proven to accurately detect toxin presence in algae sampled from the US and European waters at an unprecedented cell density of 10 cells/L. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Planar waveguide with left-handed material guiding film for refractometry applications

    OpenAIRE

    2013-01-01

    A symmetric 3-layer slab waveguide with a left-handed material as a guiding layer is examined analytically for cover refractive index detection. The TM mode dispersion relation of the proposed waveguide is investigated. The sensitivity of the proposed sensor to changes in the cover refractive index and the power flowing within each layer are presented. Some unusual features are found; for example, the sensitivity of the proposed sensor is negative. Moreover, the sensitivity improvem...

  1. Simple High-order Galerkin Finite Element Scheme for the Investigation of Both Guided and Leaky Modes in Anisotropic Planar Waveguides

    NARCIS (Netherlands)

    Uranus, H.P.; Hoekstra, H.J.W.M.; Groesen, van E.

    2004-01-01

    A simple high-order Galerkin finite element scheme is formulated to compute both the guided and leaky modes of anisotropic planar waveguides with a diagonal permittivity tensor. Transparent boundary conditions derived from the Sommerfield radiation conditions are used to model the fields at the comp

  2. Waveguide-to-planar circuit transition for millimetre-wave detectors

    CERN Document Server

    Yassin, G; King, O G; North, C E

    2008-01-01

    We present a novel design of a waveguide to microstrip or coplanar waveguide transition using a unilateral finline taper. The transition from the unilateral finline mode to the TEM microstrip mode is done directly, avoiding the antipodal finline tapers that have commonly been employed. This results in significant simplification of the design and fabrication, and shortening of the chip length, thereby reducing insertion loss. In this paper we shall present designs at 90 GHz that can be employed in superconducting tunnel junction mixers or Transition Edge Sensor bolometers, and scale-model measurements at 15 GHz.

  3. Waveguide Phase Modulator for Integrated Planar Lightwave Circuits in KTP Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR Phase II effort proposes the development and integration of a Planar Lightwave Circuit (PLC) into an all fiber-based seed laser system used in high...

  4. Recovery of Graded Index Profile of Planar Waveguide by Cubic Spline Function

    Institute of Scientific and Technical Information of China (English)

    YANG Yong; CHEN Xian-Feng; LIAO Wei-Jun; XIA Yu-Xing

    2007-01-01

    A method is proposed to recover the refractive index profile of graded waveguide from the effective indices by a cubic spline interpolation function. Numerical analysis of several typical index distributions show that the refractive index profile can be reconstructed closely to its exact profile by the presented interpolation model.

  5. Prototyping of Microfluidic Systems with Integrated Waveguides in Cyclin Olefin Copolymer

    DEFF Research Database (Denmark)

    Bundgaard, Frederik

    2007-01-01

    for rapid prototyping of this polymer is now available. These tools include: • Micro milling of fluidic channels and optical waveguides with dimensions down to 25 μm. • Spin coating of polymer layers on polymer substrates with a thickness from 100 nm to 20 μm. The spin coat layers act as a glue for joining...... handling and measurement on a single chip, and both optical and electronical components can be embedded. For polymer microsystems, integration of optical waveguides can be achieved by structuring polymers with different refractive indices. This thesis treats aspects of prototyping and fabrication...... properties makes it suited for integrated optics in microfluidic systems. Also, the engineerable glass transition temperature is an advantage, when making single-polymer systems. During the project existing fabrication methods have been adapted or improved for use with Topas, so that a number of tools...

  6. Optical Fiber Link with 1E-19 frequency stability using a Planar-Waveguide External Cavity Laser Diode

    CERN Document Server

    Clivati, Cecilia; Calonico, Davide; Levi, Filippo; Costanzo, Giovanni A; Calosso, Claudio E; Godone, Aldo

    2011-01-01

    We compare the performances of a compact planar-waveguide external cavity laser (ECL) and a traditional fiber laser (FL) frequency locked to a Fabry-P\\'erot cavity and demonstrate the possibility to use such ECL in an optical link for ultra stable frequency dissemination. A relative stability of the ECL of 1E-14 is obtained and an optical link of 100 km based on fiber spools has been realized, that reaches 2E-19 relative stability, limited by the system noise floor. The performances of ECL and FL are shown to be comparable. Thus, ECLs could be a better choice than FLs in longer optical links with amplification and regenerating stations, thanks to their cost-effectiveness, robustness and small size.

  7. Preparation Of Planar Optical SiO2-TiO2 And LiNbO3 Waveguides With A Dip Coating Method And An Embossing Technique For Fabricating Grating Couplers And Channel Waveguides

    Science.gov (United States)

    Tiefenthaler, K.; Briguet, V.; Buser, E.; Horisberger, M.; Lukosz, W.

    1983-11-01

    Planar monomode and multimode Si02-Ti02 waveguides were prepared with a dip coating method from Liquicoat solutions supplied by E. MERCK. By varying the Si02:Ti02 mixture ratio the value of the refractive index nF of the waveguiding films on Pyrex glass substrates can be chosen to lie between nF-1.6 and nF =1.36 First results on the preparation of LiNb03 waveguides are also presented. Thicknesses, refractive indices and losses of the waveguides were determined at the blue-green Ar laser wavelengths and at the He-Ne laser wavelengths λ=632.8 nm and λ=1.153 μm. With an embossing technique we fabricated surface relief gratings on Si02-Ti02 wave-guides. We used them successfully as input grating couplers. We propose to use this emboss-ing technique to fabricate channel waveguides and other integrated optical components in inorganic hard waveguiding materials such as Si02-Ti02.

  8. Planar micro-optic solar concentration using multiple imaging lenses into a common slab waveguide

    Science.gov (United States)

    Karp, Jason H.; Ford, Joseph E.

    2009-08-01

    Conventional CPV systems focus sunlight directly onto a PV cell, usually through a non-imaging optic to avoid hot spots. In practice, many systems use a shared tracking platform to mount multiple smaller aperture lenses, each concentrating light into an associated PV cell. Scaling this approach to the limit would result in a thin sheet-like geometry. This would be ideal in terms of minimizing the tracking system payload, especially since such thin sheets can be arranged into louvered strips to minimize wind-force loading. However, simply miniaturizing results in a large number of individual PV cells, each needed to be packaged, aligned, and electrically connected. Here we describe for the first time a different optical system approach to solar concentrators, where a thin lens array is combined with a shared multimode waveguide. The benefits of a thin optical design can therefore be achieved with an optimum spacing of the PV cells. The guiding structure is geometrically similar to luminescent solar concentrators, however, in micro-optic waveguide concentrators sunlight is coupled directly into the waveguide without absorption or wavelength conversion. This opens a new design space for high-efficiency CPV systems with the potential for cost reduction in both optics and tracking mechanics. In this paper, we provide optical design and preliminary experimental results of one implementation specifically intended to be compatible with large-scale roll processing. Here the waveguide is a uniform glass sheet, held between the lens array and a corresponding array of micro-mirrors self-aligned to each lens focus during fabrication.

  9. Plasmon-soliton waves in planar slot waveguides: II. Results for stationary waves and stability analysis

    CERN Document Server

    Walasik, Wiktor; Renversez, Gilles

    2016-01-01

    We describe the results of the two methods we developed to calculate the stationary nonlinear solutions in one-dimensional plasmonic slot waveguides made of a finite-thickness nonlinear dielectric core surrounded by metal regions. These two methods are described in detail in the preceding article [Walasik et al., submitted]. For symmetric waveguides, we provide the nonlinear dispersion curves obtained using the two methods and compare them. We describe the well known low-order modes and the higher-modes that were not described before. All the modes are classified into two families: modes with and without nodes. We also compare nonlinear modes with nodes with the linear modes in similar linear slot waveguides with a homogeneous core. We recover the symmetry breaking Hopf bifurcation of the first symmetric nonlinear mode toward an asymmetric mode and we show that one of the higher modes also exhibits a bifurcation. We study the behavior of the bifurcation of the fundamental mode as a function of the permittivit...

  10. Di-block co-polymer derived nanoporous polymer liquid core waveguides

    DEFF Research Database (Denmark)

    Christiansen, Mads Brøkner; Gopalakrishnan, Nimi; Sagar, Kaushal Shashikant

    2010-01-01

    Nanoporous liquid core waveguides are fabricated by selectively UV modifying a nanoporous polymer. The starting point is a diblock polymer where 1,2-polybutadiene (PB) molecules are bound to PDMS. When the PB is cross linked it self-assembles into PB with a network of 14 nm diameter PDMS filled...... pores. When the PDMS is etched, the hydrophobic PB is left with a porosity of 44%. The polymer is subsequently UV exposed through a shadow mask. This renders the exposed part hydrophilic, making it possible for water to infiltrate these areas. Water infiltration raises the refractive index, thus forming...

  11. Prototyping of Microfluidic Systems with Integrated Waveguides in Cyclin Olefin Copolymer

    DEFF Research Database (Denmark)

    Bundgaard, Frederik

    2007-01-01

    treatment of waveguides to improve the surface roughness and lower the propagation loss. The fabrication methods have been characterised, and have been optimised to minimise parameters like fabrication time, surface roughness and interface bonding strength. Using these fabrication methods, microfluidic...... the substrate, optical layers and the lid in the microfluidic systems. • Thermal bonding of polymer structures, including roll lamination of foil onto substrates. • Laser bonding of two polymer layers, including transparent on black, and transparent on transparent with a particle doped spin coating. • Thermal......, in a collaboration with IMTEK in Freiburg, Germany, an optical detection principle was developed. Using the principle of total internal reflection of a laser beam incident on a fluidic channel, detection of air bubbles is possible. The principle was used on a rotating platform as well as on non-moving systems....

  12. Comparison of waveguide properties of curved versus straight planar elastic layers

    DEFF Research Database (Denmark)

    Zadeh, Maziyar Nesari; Sorokin, Sergey

    2013-01-01

    Dispersion equations are solved for the in-plane and anti-plane wave propagation in planar elastic layer with constant curvature. The classical Lamé formulation of displacements via elastic potentials is applied and appropriate simplifications are employed. The dispersion diagrams in each case...... are compared with their counterparts for a straight layer, e.g., the classical Rayleigh–Lamb solution. The curvature-induced symmetry-breaking effects are investigated for layers with symmetric boundary conditions. The role of curvature is also investigated in the cases, when the boundary conditions...... are not symmetrical. The elementary Bernoulli–Euler theory is employed to analyze the wave guide properties of a curved planar elastic beam in its in-plane deformation. The validity range of the Bernoulli–Euler theory is assessed via comparison of dispersion diagrams....

  13. A phase insensitive all-optical router based on nonlinear lenslike planar waveguides.

    Science.gov (United States)

    Mateo, Eduardo; Liñares, Jesús

    2005-05-02

    We present the design of an all-optical router based on the properties of both propagation and interaction of Gaussian beams in lenslike planar guides. Variational results of single co- and counterpropagation are derived and used to design three integrated optical devices, that is, a header extraction device, an optical bistable device and a data routing device, which perform an ultrafast, phase-insensitive and fiber compatible routing operation in the optical domain.

  14. Study of refractive index and thickness of TiO2/ormosil planar waveguide

    Institute of Scientific and Technical Information of China (English)

    Wang Bao-Ling; Hu Li-Li

    2004-01-01

    Hybrid titania/ormosil waveguide films have been prepared by sol-gel method at low thermal treatment temperature of 150℃. The influence of processing parameters including the molar ratios of Ti(OBu)4/ glycidoxypropyltrimethoxysilane (GLYMO) and H2O/Ti(OBu)4 (expressed as R), especially aging of sol, on the refractive index and thickness of film was investigated. The optical properties of films were measured with Scanning Electron Microscope and m-line spectroscopy. The results indicate that the film thickness increases with the aging time of sol, but the variation of refractive index as a function of aging time of sol depends on the relative ratio of GLYMO to Ti-alkoxide.The relation between film thickness and corresponding sol viscosity is linear as the volume of GLYMO is 80% within the range of measured data.

  15. Full resonant transmission of semi-guided planar waves through slab waveguide steps at oblique incidence

    CERN Document Server

    Hammer, Manfred; Förstner, Jens

    2015-01-01

    Sheets of slab waveguides with sharp corners are investigated. By means of rigorous numerical experiments, we look at oblique incidence of semi-guided plane waves. Radiation losses vanish beyond a certain critical angle of incidence. One can thus realize lossless propagation through 90-degree corner configurations, where the remaining guided waves are still subject to pronounced reflection and polarization conversion. A system of two corners can be viewed as a structure akin to a Fabry-Perot-interferometer. By adjusting the distance between the two partial reflectors, here the 90-degree corners, one identifies step-like configurations that transmit the semi-guided plane waves without radiation losses, and virtually without reflections. Simulations of semi-guided beams with in-plane wide Gaussian profiles show that the effect survives in a true 3-D framework.

  16. Continuous-wave and Q-switched operation of a compact, diode-pumped Yb3+:KY(WO4)2 planar waveguide laser.

    Science.gov (United States)

    Bain, F M; Lagatsky, A A; Kurilchick, S V; Kisel, V E; Guretsky, S A; Luginets, A M; Kalanda, N A; Kolesova, I M; Kuleshov, N V; Sibbett, W; Brown, C T A

    2009-02-02

    A diode-pumped LPE-grown Yb:KYW planar waveguide laser is demonstrated in a microchip monolithic cavity configuration. Output powers as high as 148 mW and thresholds as low as 40 mW were demonstrated during continuous-wave operation. Pulses of 170 ns duration with maximum pulse energy of 44 nJ at a 722 kHz repetition rate were generated when Q-switched using a semiconductor saturable absorber mirror.

  17. Fabrication and characterization of Er+3 doped SiO2/SnO2 glass-ceramic thin films for planar waveguide applications

    Science.gov (United States)

    Guddala, S.; Chiappini, A.; Armellini, C.; Turell, S.; Righini, G. C.; Ferrari, M.; Narayana Rao, D.

    2015-02-01

    Glass-ceramics are a kind of two-phase materials constituted by nanocrystals embedded in a glass matrix and the respective volume fractions of crystalline and amorphous phase determine the properties of the glass-ceramics. Among these properties transparency is crucial in particular when confined structures, such as, dielectric optical waveguides, are considered. Moreover, the segregation of dopant rare-earth ions, like erbium, in low phonon energy crystalline medium makes these structures more promising in the development of waveguide amplifiers. Here we are proposing a new class of low phonon energy tin oxide semiconductor medium doped silicate based planar waveguides. Er3+ doped (100-x) SiO2-xSnO2 (x= 10, 20, 25 and 30mol%), glass-ceramic planar waveguide thin films were fabricated by a simple sol-gel processing and dip coating technique. XRD and HRTEM studies indicates the glass-ceramic phase of the film and the dispersion of ~4nm diameter of tin oxide nanocrystals in the amorphous phase of silica. The spectroscopic assessment indicates the distribution of the dopant erbium ions in the crystalline medium of tin oxide. The observed low losses, 0.5±0.2 dB/cm, at 1.54 μm communication wavelength makes them a quite promising material for the development of high gain integrated optical amplifiers.

  18. Power characteristics of planar index-antiguided waveguide lasers with transverse mode competition

    Directory of Open Access Journals (Sweden)

    Chaofan Wang

    2016-12-01

    Full Text Available We report comprehensive analysis of output characteristics of homogeneously broadened index-antiguided slab lasers with transverse mode competition. Robust single fundamental mode operation is achieved when the distributive modal loss due to index antiguiding dominates the output coupling loss. Maximal laser efficiency under single fundamental mode operation is investigated numerically for various combinations of single-pass gains and losses. We show analytically that an asymptotic limit of such efficiency exists that is solely determined by the loss ratio between the fundamental and 1st higher-order modes, which equals 66.7% for planar index antiguided lasers.

  19. A novel and simple coplanar waveguide-fed planar monopole antenna for ultra-wideband applications

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In this paper, a novel and simple CPW-fed planar monopole antenna is presented for UWB application. The antenna is fabricated on inexpensive FR4 substrate and fed by 50Ω CPW on the same layer. Measured data show that the antenna provides an impedance bandwidth of about 8GHz for the return loss less than 10dB. It is also observed that the radiation patterns are nearly omni-directional over the entire frequency range. Details of the proposed antenna are presented, and simulated results are presented and discussed.

  20. Response Characterization of a Fiber Optic Sensor Array with Dye-Coated Planar Waveguide for Detection of Volatile Organic Compounds

    Directory of Open Access Journals (Sweden)

    Jae-Sung Lee

    2014-07-01

    Full Text Available We have developed a multi-array side-polished optical-fiber gas sensor for the detection of volatile organic compound (VOC gases. The side-polished optical-fiber coupled with a polymer planar waveguide (PWG provides high sensitivity to alterations in refractive index. The PWG was fabricated by coating a solvatochromic dye with poly(vinylpyrrolidone. To confirm the effectiveness of the sensor, five different sensing membranes were fabricated by coating the side-polished optical-fiber using the solvatochromic dyes Reinhardt’s dye, Nile red, 4-aminophthalimide, 4-amino-N-methylphthalimide, and 4-(dimethylaminocinnamaldehyde, which have different polarities that cause changes in the effective refractive index of the sensing membrane owing to evanescent field coupling. The fabricated gas detection system was tested with five types of VOC gases, namely acetic acid, benzene, dimethylamine, ethanol, and toluene at concentrations of 1, 2,…,10 ppb. Second-regression and principal component analyses showed that the response properties of the proposed VOC gas sensor were linearly shifted bathochromically, and each gas showed different response characteristics.

  1. Laser deposition and structuring of laser active planar waveguides of Er:ZBLAN, Nd:YAG and Nd:GGG for integrated waveguide lasers

    Science.gov (United States)

    Gottmann, Jens; Moiseev, Leonid; Wortmann, Dirk; Vasilief, Ion; Starovoytova, Larisa; Ganser, Dimitri; Wagner, Ralph

    2007-02-01

    Laser radiation is used both for the deposition of the laser active thin films and for the micro structuring to define wave guiding structures for the fabrication of waveguide lasers. Thin films of Er:ZBLAN (a glass consisting of ZrF 4, BaF II, LaF 3, AlF 3, NaF, ErF 3) for green upconversion lasers (545 nm), Nd:YAG (Y 3Al 5O 12) and Nd:GGG (Gd 3Ga 5O 12) for infrared lasers (1064 nm) are produced. Manufacturing of the laser active waveguides by micro-structuring is done using fs laser ablation of the deposited films. The structural and optical properties of the films and the damping losses of the structured waveguides are determined in view of the design and the fabrication of compact and efficient diode pumped waveguide lasers. The resulting waveguides are polished, provided with resonator mirrors, pumped using diode lasers and characterized. Laser operation of a ridge waveguide structure grown by pulsed laser deposition and structured by fs laser ablation is demonstrated. A 1 μm thick, 100 μm wide and 3 mm long structured waveguide consisting of amorphous neodymium doped Gd 3Ga 5O 12 has shown laser activity at 1.068 μm when pumped by a diode laser at 808 nm.

  2. Fabrication and optical testing of hybrid SiO2: azo-polymer based planar waveguides for NLO/SHG laser emission

    Science.gov (United States)

    Torres-Zúñiga, V.; Morales-Saavedra, O. G.; Pérez-Martínez, A. L.

    2015-01-01

    Predesigned push-pull azo-dye polymers were homogeneously dispersed within a SiO2 sol-gel matrix synthesized via the sonogel (SG) route. High-quality spin-coated films were obtained with these hybrid structures in the liquid sol-phase. The spectroscopic UV- Vis analyses reveal the appropriate insertion of these organic compounds within the highly pure SG-environment whereas the thermal (DSC) analysis and photoacoustic measurements evidence the thermomechanical stability of the amorphous hybrid layers. As the optical attenuation, refractive index and film thickness values of the obtained films are adequate for opto-electronic applications; these hybrid films were implemented to fabricate optical waveguiding prototypes. In this sense, functional planar waveguides were fabricated for nonlinear optical (NLO) applications after performing a molecular ordering via a corona DC-poling procedure in order to achieve a macroscopic polar order (ferroelectric and noncentrosymmetric arrangement of the organic chromophores). The poled films were then able to exhibit stable NLO-waveguiding effects as excited with a Nd:YAG laser system in order to generate second harmonic waves travelling within the planar layer.

  3. Detection of the cyanobacterial toxin, microcystin-LR, using a novel recombinant antibody-based optical-planar waveguide platform.

    Science.gov (United States)

    Murphy, Caroline; Stack, Edwina; Krivelo, Svetlana; McPartlin, Daniel A; Byrne, Barry; Greef, Charles; Lochhead, Michael J; Husar, Greg; Devlin, Shauna; Elliott, Christopher T; O'Kennedy, Richard J

    2015-05-15

    Microcystins are a major group of cyanobacterial heptapeptide toxins found in freshwater and brackish environments. There is currently an urgent requirement for highly-sensitive, rapid and in-expensive detection methodologies for these toxins. A novel single chain fragment variable (scFv) fragment was generated and is the first known report of a recombinant anti-microcystin avian antibody. In a surface plasmon resonance-based immunoassay, the antibody fragment displayed cross-reactivity with seven microcystin congeners (microcystin-leucine-arginine (MC-LR) 100%, microcystin-tyrosine-arginine (MC-YR) 79.7%, microcystin-leucine-alanine (MC-LA) 74.8%, microcystin-leucine-phenylalanine (MC-LF) 67.5%, microcystin-leucine-tryptophan (MC-LW) 63.7%, microcystin-arginine-arginine (MC-RR) 60.1% and nodularin (Nod) 69.3%, % cross reactivity). Following directed molecular evolution of the parental clone the resultant affinity-enhanced antibody fragment was applied in an optimized fluorescence immunoassay on a planar waveguide detection system. This novel immuno-sensing format can detect free microcystin-LR with a functional limit of detection of 0.19 ng mL(-1)and a detection range of 0.21-5.9 ng mL(-1). The assay is highly reproducible (displaying percentage coefficients of variance below 8% for intra-day assays and below 11% for inter-day assays), utilizes an inexpensive cartridge system with low reagent volumes and can be completed in less than twenty minutes.

  4. Planar optical waveguide based sandwich assay sensors and processes for the detection of biological targets including protein markers, pathogens and cellular debris

    Science.gov (United States)

    Martinez, Jennifer S.; Swanson, Basil I.; Grace, Karen M.; Grace, Wynne K.; Shreve, Andrew P.

    2009-06-02

    An assay element is described including recognition ligands bound to a film on a single mode planar optical waveguide, the film from the group of a membrane, a polymerized bilayer membrane, and a self-assembled monolayer containing polyethylene glycol or polypropylene glycol groups therein and an assay process for detecting the presence of a biological target is described including injecting a biological target-containing sample into a sensor cell including the assay element, with the recognition ligands adapted for binding to selected biological targets, maintaining the sample within the sensor cell for time sufficient for binding to occur between selected biological targets within the sample and the recognition ligands, injecting a solution including a reporter ligand into the sensor cell; and, interrogating the sample within the sensor cell with excitation light from the waveguide, the excitation light provided by an evanescent field of the single mode penetrating into the biological target-containing sample to a distance of less than about 200 nanometers from the waveguide thereby exciting the fluorescent-label in any bound reporter ligand within a distance of less than about 200 nanometers from the waveguide and resulting in a detectable signal.

  5. Femtosecond pulses at 50-W average power from an Yb:YAG planar waveguide amplifier seeded by an Yb:KYW oscillator.

    Science.gov (United States)

    Leburn, Christopher G; Ramírez-Corral, Cristtel Y; Thomson, Ian J; Hall, Denis R; Baker, Howard J; Reid, Derryck T

    2012-07-30

    We report the demonstration of a high-power single-side-pumped Yb:YAG planar waveguide amplifier seeded by an Yb:KYW femtosecond laser. Five passes through the amplifier yielded 700-fs pulses with average powers of 50 W at 1030 nm. A numerical simulation of the amplifier implied values for the laser transition saturation intensity, the small-signal intensity gain coefficient and the gain bandwidth of 10.0 kW cm(-2), 1.6 cm(-1), and 3.7 nm respectively, and identified gain-narrowing as the dominant pulse-shaping mechanism.

  6. NIR luminescent Er{sup 3+}/Yb{sup 3+} co-doped SiO{sub 2}-ZrO{sub 2} nanostructured planar and channel waveguides: Optical and structural properties

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Cesar dos Santos [Departamento de Quimica, Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Av. Bandeirantes, 3900, 14040-901, Ribeirao Preto/SP (Brazil); Ferrari, Jefferson Luis [Grupo de Pesquisa em Quimica de Materiais - (GPQM), Departamento de Ciencias Naturais, Universidade Federal de Sao Joao Del Rei, Campus Dom Bosco, Praca Dom Helvecio, 74, 36301-160, Sao Joao Del Rei, MG (Brazil); Oliveira, Drielly Cristina de [Departamento de Quimica, Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Av. Bandeirantes, 3900, 14040-901, Ribeirao Preto/SP (Brazil); Maia, Lauro June Queiroz [Grupo Fisica de Materiais, Instituto de Fisica, UFG, Campus Samambaia, Caixa Postal 131, 74001-970, Goiania/GO (Brazil); Gomes, Anderson Stevens Leonidas [Departamento de Fisica, Universidade Federal de Pernambuco, Cidade Universitaria, Recife/PE, 50670-901 (Brazil); Ribeiro, Sidney Jose Lima [Laboratorio de Materiais Fotonicos, Instituto de Quimica, UNESP, Caixa Postal 355, 14801-970, Araraquara/SP (Brazil); and others

    2012-09-14

    Optical and structural properties of planar and channel waveguides based on sol-gel Er{sup 3+} and Yb{sup 3+} co-doped SiO{sub 2}-ZrO{sub 2} are reported. Microstructured channels with high homogeneous surface profile were written onto the surface of multilayered densified films deposited on SiO{sub 2}/Si substrates by a femtosecond laser etching technique. The densification of the planar waveguides was evaluated from changes in the refractive index and thickness, with full densification being achieved at 900 Degree-Sign C after annealing from 23 up to 500 min, depending on the ZrO{sub 2} content. Crystal nucleation and growth took place together with densification, thereby producing transparent glass ceramic planar waveguides containing rare earth-doped ZrO{sub 2} nanocrystals dispersed in a silica-based glassy host. Low roughness and crack-free surface as well as high confinement coefficient were achieved for all the compositions. Enhanced NIR luminescence of the Er{sup 3+} ions was observed for the Yb{sup 3+}-codoped planar waveguides, denoting an efficient energy transfer from the Yb{sup 3+} to the Er{sup 3+} ion. Highlights: Black-Right-Pointing-Pointer Sol-gel high NIR luminescent nanostructured planar and channel waveguides. Black-Right-Pointing-Pointer Microstructured channels written by a femtosecond laser etching technique. Black-Right-Pointing-Pointer Transparent glass ceramic with rare earth-doped ZrO{sub 2} nanocrystals in a silica host. Black-Right-Pointing-Pointer Enhanced NIR luminescence, efficient energy transfer from the Yb{sup 3+} to the Er{sup 3+} ion. Black-Right-Pointing-Pointer New planar channel waveguides to be applied as EDWA in the C telecommunication band.

  7. Optical and fluorescent properties of Y{sub 2}O{sub 3} sol-gel planar waveguides containing Tb{sup 3+} doped nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Y.C.; Garapon, C.; Bazzi, R.; Pillonnet, A.; Tillement, O.; Mugnier, J. [Universite de Lyon, Universite Lyon 1, CNRS, Laboratoire de Physico-Chimie des Materiaux Luminescents, Villeurbanne (France)

    2007-06-15

    Terbium doped Y{sub 2}O{sub 3} planar waveguides were fabricated by sol-gel process and dip-coating using yttrium acetate as precursor. Two different doping modes were compared, i.e. introduction in the sol of dispersed Tb{sup 3+}ions from dissolved Tb(NO{sub 3}){sub 3}, or of nanoparticles of Tb{sub 2}O{sub 3} or [Y{sub 2}O{sub 3}:50% Tb] from an alcoholic suspension. The chemical and nanostructural properties were analyzed by infrared spectroscopy, transmission electron microscopy and X-ray diffraction. The Tb{sup 3+} fluorescence properties were studied as a function of temperature and atmosphere of the thermal treatments, and of the Tb{sup 3+} concentration. The fluorescence properties are discussed in relation to the quenching mechanisms induced by Tb{sup 4+} transformation, residual OH groups, and crystallites size and structure. Optical propagation losses of the Tb doped Y{sub 2}O{sub 3} planar waveguides related to the doping modes and Tb{sup 3+} concentration are presented. Doping sol-gel films by nanoparticles is shown to be a valuable alternative to the conventional doping from dissolved terbium salt. (orig.)

  8. Annealing behaviour of structure and morphology and its effects on the optical gain of Er3+/Yb3+ co-doped Al2O3 planar waveguide amplifier

    Institute of Scientific and Technical Information of China (English)

    Tan Na; Zhang Qing-Yu

    2006-01-01

    Using transmission electron microscopy (TEM) and x-ray diffraction analysis, we have studied the structural and morphological evolution of highly Er/Yb co-doped Al2O3 films in the temperature range from 600℃-900℃. Bycomparison with TEM observation, the annealing behaviours of photoluminescence (PL) emission and optical loss were found to have relation to the structure and morphology. The increase of PL intensity and optical loss above 800℃ might result from the crystallization of amorphous Al2O3 films. Based on the study on the structure and morphology,a rate equation propagation model of a multilevel system was used to calculate the optical gains of Er-doped Al2O3 planar waveguide amplifiers involving the variation of PL efficiency and optical loss with annealing temperature. It was found that the amplifiers had an optimized optical gain at the temperature corresponding to the minimum of optical loss, rather than at the temperature corresponding to the maximum of PL efficiency, suggesting that the optical loss is a key factor for determining the optical gain of an Er-doped Al2O3 planar waveguide amplifier.

  9. Research and Design of Ge0.6Si0.4/Si Strained-layer Superlattice Planar Optical Waveguide

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Calculation shows that the refraction index of Ge0.6Si0.4/Si strained-layer superlattice n≈3.64, when Lw=9nm and Lb=24nm. An algorithm of numerical iteration for effective refraction index is employed to obtain different effective refraction indexes at different thickness (L). As a result, the thickness of Ge0.6Si0.4/Si strained-layer superlattice optical waveguide, L≤363nm, can be determined, which is very important for designing waveguide devices. An optical waveguide can be made into a nanometer device by using Ge0.6Si0.4/Si strained-layer superlattice.

  10. Label-free antibody detection using band edge fringes in SOI planar photonic crystal waveguides in the slow-light regime.

    Science.gov (United States)

    García-Rupérez, Jaime; Toccafondo, Veronica; Bañuls, María José; Castelló, Javier García; Griol, Amadeu; Peransi-Llopis, Sergio; Maquieira, Ángel

    2010-11-08

    We report experimental results of label-free anti-bovine serum albumin (anti-BSA) antibody detection using a SOI planar photonic crystal waveguide previously bio-functionalized with complementary BSA antigen probes. Sharp fringes appearing in the slow-light regime near the edge of the guided band are used to perform the sensing. We have modeled the presence of these band edge fringes and demonstrated the possibility of using them for sensing purposes by performing refractive index variations detection, achieving a sensitivity of 174.8 nm/RIU. Then, label-free anti-BSA biosensing experiments have been carried out, estimating a surface mass density detection limit below 2.1 pg/mm2 and a total mass detection limit below 0.2 fg.

  11. Dielectric Waveguide lasers

    NARCIS (Netherlands)

    Pollnau, Markus; Orlovic, V.A.; Pachenko, V.; Scherbakov, I.A.

    2007-01-01

    Our recent results on planar and channel waveguide fabrication and lasers in the dielectric oxide materials Ti:sapphire and rare-earth-ion-doped potassium yttrium double tungstate (KYW) are reviewed. We have employed waveguide fabrication methods such as liquid phase epitaxy and reactive ion etching

  12. 基于平板型导光板的太阳能聚光系统%Sollar Concentrating System Based on Planar Waveguide

    Institute of Scientific and Technical Information of China (English)

    郝雯雯; 余桂英; 胡兴

    2012-01-01

    针对传统线性聚光系统聚光光斑辐照度不均匀的问题,提出了一种由曲面线聚焦菲涅耳聚光器阵列及平板型导光板所组成的、系统高度小于40 mm的小体积聚光系统方案,建立了曲面线聚焦菲涅耳透镜的一般方程,给出导光板V形槽设计公式,并采用正交试验法和光学仿真实验对聚光器系统的各项结构参数进行优化设计,同时分析了曲面线聚焦菲涅耳的加工误差及导光板安装偏角误差的影响.结果表明:优化后系统在采光面积500 mm×200 mm、聚光比50倍时,聚光效率可达75%,聚焦光斑均匀性优于88%,且入射太阳光偏角在士7°内聚光效率大于50%.通过拼接可获得不同聚光倍数系统,由仿真实验得出在160倍聚光比内,效率高于50%,均匀性优于85%.%A solar concentrating system is designed to solve the nonuniform illumination distribution problem of the flares through traditional concentrating systems with line focus. This concentrator system consists of curved cylindrical Fresnel lens array and a planar waveguide. A general formula of curved Fresnel with line focus and the design formula of the V-groove of the waveguide are presented. The system is in a small volume. with the total height less than 40 mm. Through orthogonal test and optical simulation, structure parameters of the system are optimized. Meanwhile, the influences of the machining error of the curved line focus Fresnel lenses and the installation error of the waveguide are discussed. It turns out that the optical efficiency of the optimized system with a lighting area of 500 mm × 200 mm in the condition of 50 × geometric concentration is about 75% and the illumination uniformity is above 88%. Simultaneously the optical efficiency is over 50% within ±7° declination angle of the incident light. Different concentration can be reached by splicing and it is proved by simulation that the optical efficiency is above 50% and the

  13. Optical waveguide enhanced photovoltaics.

    Science.gov (United States)

    Rühle, Sven; Greenwald, Shlomit; Koren, Elad; Zaban, Arie

    2008-12-22

    Enhanced light to electric power conversion efficiency of photovoltaic cells with a low absorbance was achieved using waveguide integration. We present a proof of concept using a very thin dye-sensitized solar cell which absorbed only a small fraction of the light at normal incidence. The glass substrate in conjunction with the solar cells reflecting back contact formed a planar waveguide, which lead to more than four times higher conversion efficiency compared to conventional illumination at normal incidence. This illumination concept leads to a new type of multi-junction PV systems based on enforced spectral splitting along the waveguide.

  14. Waveguide mutually pumped phase conjugators

    OpenAIRE

    James, S. W.; Youden, K.E.; Jeffrey, P. M.; EASON, R. W.; Chandler, P.J.; Zhang, L.; Townsend, P.D.

    1993-01-01

    The operation of the Bridge Mutually Pumped Phase Conjugator is reported in a planar waveguide structure in photorefractive BaTiO3. The waveguide was fabricated by the technique of ion implantation. using 1.5 MeV H+ at a dose of 10^16 ions/cm^2. An order of magnitude decrease in response time is observed in the waveguide as compared to typical values obtained in bulk crystals, probably resulting from a combination of the optical confinement within the waveguide, and possibly modification of t...

  15. Proposals for Fabrication of Long-Period Grating in LiNbO3 Strip Waveguides

    Institute of Scientific and Technical Information of China (English)

    ZHANG De-Long; YANG Qing-Zhong; E. Y. B. Pun

    2008-01-01

    @@ The structure of a strip LiNbO3 waveguide clad with a planar LiNbO3 wayeguide is proposed to fabricate a long-period waveguide grating (LPWG). It is shown theoretically that an LPWG device based on such a special LiNbO3 waveguide structure is of the merit of thermal stability. The methods for fabrication of planar waveguide, channel waveguide and grating are suggested and discussed. Detailed design consideration is exemplified based on a soft-proton-exchange planar waveguide clad Ti-diffused LiNbO3 (Z-cut) strip waveguide.

  16. 10 Gbps Colorless Optical Source in Wavelength-Division Multiplexed Passive Optical Networks for Monolithic Integration of Deep-Ridge Waveguide Electroabsorption Modulator with Planar Buried-Heterostructure Semiconductor Optical Amplifier

    Science.gov (United States)

    Kim, Dong Churl; Kim, Ki Soo; Kim, Hyun-Soo; Choi, Byung-Seok; Kwon, O.-Kyun

    2012-05-01

    For the 10 Gbps colorless optical source in wavelength-division multiplexed passive optical networks (WDM-PONs), we have fabricated a semiconductor optical amplifier-reflective electorabsorption modulator (SOA-REAM) by monolithic integration of deep-ridge waveguide REAM (DRW-REAM) with planar buried-heterostructure (PBH) SOA using a PNP-current blocking layer. The SOA-REAM has a spot-size convertor for easy fiber coupling. Using a butterfly module with an SMA connector, we have packaged the SOA-REAM. At a -10 dBm input power of 1550 nm, the saturation output power is about 6 dBm. At 10.7 Gbps, we can obtain clear eye diagrams, and the power penalty at 10-9 bit-error rate (BER) after 20 km transmission is less than 1 dB over 35 nm.

  17. Effect of planar extension on the structure and mechanical properties of polystyrene-poly(ethylene-¤co¤-butylene)-polystyrene triblock copolymers

    DEFF Research Database (Denmark)

    Daniel, C.; Hamley, I.W.; Mortensen, K.

    2000-01-01

    with a spherical microstructure adopts a body-centred cubic (bcc) structure with a [111] orientation along the Row direction. For the pre-oriented triblock with a cylindrical microstructure, the cylinder axis is aligned along the extensional Row direction. Investigation of the mechanical properties showed...... that Young's moduli of the pre-oriented copolymers are highly anisotropic. Specimens were then subject to uniaxial deformation along the extensional Row direction and at the same time microstructural changes induced by the deformation were investigated by SANS. It was found that the deformation of the bcc...

  18. Planar micro-optic solar concentrator

    National Research Council Canada - National Science Library

    Karp, Jason H; Tremblay, Eric J; Ford, Joseph E

    2010-01-01

    We present a new approach to solar concentration where sunlight collected by each lens in a two-dimensional lens array is coupled into a shared, planar waveguide using localized features placed at each lens focus...

  19. Progress on erbium-doped waveguide components

    DEFF Research Database (Denmark)

    Bjarklev, Anders Overgaard; Berendt, Martin Ole; Broeng, Jes;

    1997-01-01

    The recent development in erbium-doped fiber amplifiers, and fiber lasers is reviewed. Also the latest results on planar erbium-doped waveguide amplifiers and high erbium concentration characterisation methods are presented......The recent development in erbium-doped fiber amplifiers, and fiber lasers is reviewed. Also the latest results on planar erbium-doped waveguide amplifiers and high erbium concentration characterisation methods are presented...

  20. Two-dimensional Kagome photonic bandgap waveguide

    DEFF Research Database (Denmark)

    Nielsen, Jens Bo; Søndergaard, Thomas; Libori, Stig E. Barkou;

    2000-01-01

    The transverse-magnetic photonic-bandgap-guidance properties are investigated for a planar two-dimensional (2-D) Kagome waveguide configuration using a full-vectorial plane-wave-expansion method. Single-moded well-localized low-index guided modes are found. The localization of the optical modes...... is investigated with respect to the width of the 2-D Kagome waveguide, and the number of modes existing for specific frequencies and waveguide widths is mapped out....

  1. The Research of APTS Modification on Silicon Structure Surface Based on Planar Waveguide%平面波导硅基结构表面的APTES修饰研究

    Institute of Scientific and Technical Information of China (English)

    王景雪; 薛晨阳; 刘超; 王永华; 臧俊斌; 韦丽萍

    2013-01-01

    3-氨丙基三乙氧基硅烷(APTES)是一种常用的表面修饰剂,通过化学键合的方式覆盖在硅结构表面形成APTES膜层,用以链接功能性生物分子.本文基于平面波导生物传感器器件的研究,通过对结构表面膜层的物理化学特性进行分析,对实验方案进行优化,降低表面微粗糙度,提升生物分子膜层的活性.文中在相同的实验环境下,将APTES分别溶于PBS、乙醇、甲苯溶液,进行APTES分子膜的生成.通过原子力扫描显微镜(AFM)、接触角测试仪、X-射线光谱仪(XPS)对不同样品表面微粗糙度(RMS)、接触角、成分等物理化学特性进行分析,确定应用于光学生物传感器器件APTES表面修饰的最佳配剂,为提高平面波导生物传感器的灵敏度提供了理论支持.%3-Aminopropyltriethoxysilane ( APTES) is a kind of common surface modification agents, which can be covered on the silicon structure surface by chemical bonding to link functional biological molecules. Based on the research of Planar Waveguide Bio-sensor devices, surface film layer physical and chemical characteristics were analyzed,and the experiment scheme was,optimized,to make micro roughness lower and improve biological molecular film activity. APTES is dissolved separately in PBS,ethanol and toluene to form APTES molecular film under the same conditions. Physical and chemical properties like Root Mean Square (RMS) .contact angle and component of different sample surfaces are analyzed by Atom Forces Microscope( AFM) .Contact Angle Tester and X-ray Photoelectron Spec-troscopy(XPS). Finalized the best solvent of surface modification on Si structure with APTES applying on optical biosensor and provided theoretical support for improving the sensitivity of planar waveguide optical biosensors.

  2. Dielectric Covered Planar Antennas

    Science.gov (United States)

    Llombart Juan, Nuria (Inventor); Lee, Choonsup (Inventor); Chattopadhyay, Goutam (Inventor); Gill, John J. (Inventor); Skalare, Anders J. (Inventor); Siegel, Peter H. (Inventor)

    2014-01-01

    An antenna element suitable for integrated arrays at terahertz frequencies is disclosed. The antenna element comprises an extended spherical (e.g. hemispherical) semiconductor lens, e.g. silicon, antenna fed by a leaky wave waveguide feed. The extended spherical lens comprises a substantially spherical lens adjacent a substantially planar lens extension. A couple of TE/TM leaky wave modes are excited in a resonant cavity formed between a ground plane and the substantially planar lens extension by a waveguide block coupled to the ground plane. Due to these modes, the primary feed radiates inside the lens with a directive pattern that illuminates a small sector of the lens. The antenna structure is compatible with known semiconductor fabrication technology and enables production of large format imaging arrays.

  3. Plasmonic Antennas Hybridized with Dielectric Waveguides

    CERN Document Server

    Arango, Felipe Bernal; Koenderink, A Femius

    2013-01-01

    For the purpose of using plasmonics in an integrated scheme where single emitters can be probed efficiently, we experimentally and theoretically study the scattering properties of single nano-rod gold antennas as well as antenna arrays placed on one-dimensional dielectric silicon nitride waveguides. Using real space and Fourier microscopy correlated with waveguide transmission measurements, we quantify the spectral properties, absolute strength and directivity of scattering. The scattering processes can be well understood in the framework of the physics of dipolar objects placed on a planar layered environment with a waveguiding layer. We use the single plasmonic structures on top of the waveguide as dipolar building blocks for new types of antennas where the waveguide enhances the coupling between antenna elements. We report on waveguide hybridized Yagi-Uda antennas which show directionality in out-coupling of guided modes as well as directionality for in-coupling into the waveguide of localized excitations ...

  4. Homogenization analysis of complementary waveguide metamaterials

    Science.gov (United States)

    Landy, Nathan; Hunt, John; Smith, David R.

    2013-11-01

    We analyze the properties of complementary metamaterials as effective inclusions patterned into the conducting walls of metal waveguide structures. We show that guided wave metamaterials can be homogenized using the same retrieval techniques used for volumetric metamaterials, leading to a description in which a given complementary element is conceptually replaced by a block of material within the waveguide whose effective permittivity and permeability result in equivalent scattering characteristics. The use of effective constitutive parameters for waveguide materials provides an alternative point-of-view for the design of waveguide and microstrip based components, including planar lenses and filters, as well as devices with derived from a bulk material response. In addition to imparting effective constitutive properties to the waveguide, complementary metamaterials also couple energy from waveguide modes into radiation. Thus, complementary waveguide metamaterials can be used to modify and optimize a variety of antenna structures.

  5. Development of Co-Sintering Process for Effective Fabrication of Direct-Write Planer Waveguide

    Institute of Scientific and Technical Information of China (English)

    W.Jung; S.; Yoo; S.; Boo; U.-C.; Paek; W.-T.; Han

    2003-01-01

    We propose a co-sintering process for effective fabrication of three-layered structure for direct-write planar waveguide. Processing parameters and optical properties of the waveguide was investigated.

  6. Optical waveguides in laser crystals

    NARCIS (Netherlands)

    Pollnau, Markus; Romanyuk, Yaroslav E.

    2007-01-01

    This article reviews the recent research on different types of planar and channel crystalline optical waveguides, fabrication methods such as liquid phase epitaxy, pulsed laser deposition, thermal bonding, reactive ion or ion beam etching, wet chemical etching, ion in-diffusion, proton exchange, ion

  7. Glass Waveguides for Periodic Poling

    DEFF Research Database (Denmark)

    Fage-Pedersen, Jacob; Jacobsen, Rune Shim; Kristensen, Martin

    2005-01-01

    Planar silica-based waveguide devices have been developed for second-harmonic generation by poling with periodic electrodes. We show that detrimental charge transport can occur along interfaces, but with proper choice of fabrication, high-quality devices are obtained....

  8. Glass Waveguides for Periodic Poling

    DEFF Research Database (Denmark)

    Fage-Pedersen, Jacob; Jacobsen, Rune Shim; Kristensen, Martin

    2005-01-01

    Planar silica-based waveguide devices have been developed for second-harmonic generation by poling with periodic electrodes. We show that detrimental charge transport can occur along interfaces, but with proper choice of fabrication, high-quality devices are obtained....

  9. Applicability of Bisphenol A Detection by a Planar Waveguide Fluorescent Biosensor%基于平面波导型荧光免疫传感器的双酚A检测适用性研究

    Institute of Scientific and Technical Information of China (English)

    徐玮琦; 张永明; 周小红; 施汉昌

    2015-01-01

    双酚A是一种环境内分泌干扰物,逐渐受到国内外广泛关注.平面波导型荧光免疫传感器可以对水样中存在的痕量双酚A进行快速高灵敏度检测.在最优检测条件下测得双酚A标准曲线的检出限为(0.04±0.007)μg•L-1,线性区间为0.16~22.40μg•L-1,半抑制浓度为(1.67±0.47)μg•L-1.加入0.5%的EDTA到样品溶液中可以削弱水体硬度的干扰,并在最优条件下测得4种实际水样的加标回收率在88%~111%之间,相对标准偏差小于15%,表明该方法可以运用于实际水样中双酚A的检测.%As a kind of environmental endocrine disruptors, bisphenol A received a wide attention around the world. The planar waveguide fluorescent biosensor can rapidly and sensitively detect traceable bisphenol A in water samples. Under the optimized test conditions, the typical calibration curve for BPA determination by the biosensor showed a detection limit of(0. 04 ± 0. 007) μg•L-1. The linear response ranged from 0. 16 μg•L-1 to 22. 40 μg•L-1 . The 50% inhibition concentration ( IC50 ) was ( 1. 67 ± 0. 47 )μg•L-1 . By means of adding 0. 5% EDTA to sample solutions could weaken the interference of water hardness. Under the optimal conditions, the recovery ratios for four kinds of real water samples were in the range of 88% to 111%, with R. S. D. less than 15%. The results indicate that this method features the potential in the practical detections of bisphenol A in real water samples.

  10. Metal-clad waveguide sensors

    DEFF Research Database (Denmark)

    Skivesen, Nina

    This work concerns planar optical waveguide sensors for biosensing applications, with the focus on deep-probe sensing for micron-scale biological objects like bacteria and whole cells. In the last two decades planar metal-clad waveguides have been brieflyintroduced in the literature applied...... for various biosensing applications, however a thorough study of the sensor configurations has not been presented, but is the main subject of this thesis. Optical sensors are generally well suited for bio-sensing asthey show high sensitivity and give an immediate response for minute changes in the refractive...... index of a sample, due to the high sensitivity of optical bio-sensors detection of non-labeled biological objects can be performed. The majority of opticalsensors presented in the literature and commercially available optical sensors are based on evanescent wave sensing, however most of these sensors...

  11. Direct UV-writing of waveguides

    DEFF Research Database (Denmark)

    Færch, Kjartan Ullitz

    2003-01-01

    The research presented in this phd thesis is concerned about fabrication of waveguide structures in photosensitized germanosilica thin films by exposure to Ultra-violet (UV) radiation. Using a high pressure loading system and a waveguide fabrication setup, planar waveguiding structures with an UV...... induced refractive index change of more than 10-2 have been obtained. New insight, with respect to understanding the UV induced index change obtained by direct UV writing, has been provided, through experiments conducted with such high-pressure loaded germanosilica samples. This include measurements...

  12. Waveguide-based optical chemical sensor

    Science.gov (United States)

    Grace, Karen M.; Swanson, Basil I.; Honkanen, Seppo

    2007-03-13

    The invention provides an apparatus and method for highly selective and sensitive chemical sensing. Two modes of laser light are transmitted through a waveguide, refracted by a thin film host reagent coating on the waveguide, and analyzed in a phase sensitive detector for changes in effective refractive index. Sensor specificity is based on the particular species selective thin films of host reagents which are attached to the surface of the planar optical waveguide. The thin film of host reagents refracts laser light at different refractive indices according to what species are forming inclusion complexes with the host reagents.

  13. A Substrate Integrated Waveguide Sensor for Measurement of Dielectric Properties of Biomass Materials

    Science.gov (United States)

    Substrate integrated waveguide- based sensors balance the performance and well known design techniques of classical waveguides with the cheaper and more adaptable aspects of planar circuits. Propagation characteristics are similar to waveguides with the design retaining many positive aspects of wave...

  14. Optical waveguide focusing system with short free-working distance

    NARCIS (Netherlands)

    Wang, H.; Groen, F.H.; Pereira, S.F.; Braat, J.J.M.

    2003-01-01

    In photonics, light usually diffracts in all directions when it emerges from a planar optical waveguide. Besides this fact, in this letter we show that a waveguide with a rectangular cross section can be turned to a focusing system by using three-dimensional self-imaging technique. We obtained a con

  15. Field of view of limitations in see-through HMD using geometric waveguides.

    Science.gov (United States)

    DeHoog, Edward; Holmstedt, Jason; Aye, Tin

    2016-08-01

    Geometric waveguides are being integrated into head-mounted display (HMD) systems, where having see-through capability in a compact, lightweight form factor is required. We developed methods for determining the field of view (FOV) of such waveguide HMD systems and have analytically derived the FOV for waveguides using planar and curved geometries. By using real ray-tracing methods, we are able to show how the geometry and index of refraction of the waveguide, as well as the properties of the coupling optics, impact the FOV. Use of this analysis allows one to determine the maximum theoretical FOV of a planar or curved waveguide-based system.

  16. Waveguide-Based Biosensors for Pathogen Detection

    Directory of Open Access Journals (Sweden)

    Nile Hartman

    2009-07-01

    Full Text Available Optical phenomena such as fluorescence, phosphorescence, polarization, interference and non-linearity have been extensively used for biosensing applications. Optical waveguides (both planar and fiber-optic are comprised of a material with high permittivity/high refractive index surrounded on all sides by materials with lower refractive indices, such as a substrate and the media to be sensed. This arrangement allows coupled light to propagate through the high refractive index waveguide by total internal reflection and generates an electromagnetic wave—the evanescent field—whose amplitude decreases exponentially as the distance from the surface increases. Excitation of fluorophores within the evanescent wave allows for sensitive detection while minimizing background fluorescence from complex, “dirty” biological samples. In this review, we will describe the basic principles, advantages and disadvantages of planar optical waveguide-based biodetection technologies. This discussion will include already commercialized technologies (e.g., Corning’s EPIC® Ô, SRU Biosystems’ BIND™, Zeptosense®, etc. and new technologies that are under research and development. We will also review differing assay approaches for the detection of various biomolecules, as well as the thin-film coatings that are often required for waveguide functionalization and effective detection. Finally, we will discuss reverse-symmetry waveguides, resonant waveguide grating sensors and metal-clad leaky waveguides as alternative signal transducers in optical biosensing.

  17. Trenches for building blocks of advanced planar components

    DEFF Research Database (Denmark)

    Haiyan, Ou

    2004-01-01

    Trenches are fundamental structures used to build advanced optical planar waveguide components. In this letter, the fabrication of trenches across silica-on-silicon waveguides using inductively coupled plasma etching is presented. These trenches were etched deep into the silicon substrate...

  18. Wave-guided optical waveguides

    DEFF Research Database (Denmark)

    Palima, Darwin; Bañas, Andrew Rafael; Vizsnyiczai, George

    2012-01-01

    This work primarily aims to fabricate and use two photon polymerization (2PP) microstructures capable of being optically manipulated into any arbitrary orientation. We have integrated optical waveguides into the structures and therefore have freestanding waveguides, which can be positioned anywhe...... bridge the diffraction barrier. This structure-mediated paradigm may be carried forward to open new possibilities for exploiting beams from far-field optics down to the subwavelength domain....

  19. Single- and double energy N{sup +} ion irradiated planar optical waveguides in Er: Tungsten–tellurite oxide glass and sillenite type Bismuth Germanate crystals working up to telecommunications wavelengths

    Energy Technology Data Exchange (ETDEWEB)

    Bányász, I., E-mail: banyasz@sunserv.kfki.hu [Department of Crystal Physics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest (Hungary); Zolnai, Z.; Fried, M.; Lohner, T. [Research Institute for Technical Physics and Materials Science, Research Centre for Natural Sciences, Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest (Hungary); Berneschi, S.; Righini, G.C. [MDF-Lab, “Nello Carrara” Institute of Applied Physics, IFAC-CNR, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy); “Enrico Fermi” Center for Study and Research, Piazza del Viminale 2, 00184 Roma (Italy); Pelli, S.; Nunzi-Conti, G. [MDF-Lab, “Nello Carrara” Institute of Applied Physics, IFAC-CNR, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy)

    2013-07-15

    Ion implantation proved to be a universal technique for producing waveguides in most optical materials. Tellurite glasses are good hosts of rare-earth elements for the development of fibre and integrated optical amplifiers and lasers covering all the main telecommunication bands. Er{sup 3+}-doped tellurite glasses are good candidates for the fabrication of broadband amplifiers in wavelength division multiplexing around 1.55 μm, as they exhibit large stimulated cross sections and broad emission bandwidth. Fabrication of channel waveguides in such a material via N{sup +} ion implantation was reported recently. Sillenite type Bismuth Germanate (BGO) crystals are good nonlinear optical materials. Parameters of waveguide fabrication in both materials via implantation of MeV-energy N{sup +} ions were optimized. First single-energy implantations at 3.5 MeV at various fluences were applied. Waveguide operation up to 1.5 μm was observed in both materials. Then double-energy implantations at a fixed upper energy of 3.5 MeV and lower energies between 2.5 and 3.1 MeV were performed to suppress leaky modes by increasing barrier width. Improvement of waveguide characteristics was found by m-line spectroscopy and spectroscopic ellipsometry.

  20. Optical touch screen based on waveguide sensing

    DEFF Research Database (Denmark)

    Pedersen, Henrik Chresten; Jakobsen, Michael Linde; Hanson, Steen Grüner

    2011-01-01

    We disclose a simple, optical touch screen technique based on a planar injection molded polymer waveguide, a single laser, and a small linear detector array. The solution significantly reduces the complexity and cost as compared to existing optical touch technologies. Force detection of a touchin...... finger is also demonstrated....

  1. Optical touch screen based on waveguide sensing

    Science.gov (United States)

    Pedersen, Henrik C.; Jakobsen, Michael L.; Hanson, Steen G.; Mosgaard, Morten; Iversen, Theis; Korsgaard, Jorgen

    2011-08-01

    We disclose a simple, optical touch screen technique based on a planar injection molded polymer waveguide, a single laser, and a small linear detector array. The solution significantly reduces the complexity and cost as compared to existing optical touch technologies. Force detection of a touching finger is also demonstrated.

  2. Sub-micrometer waveguide for nano-optics

    DEFF Research Database (Denmark)

    Rottwitt, Karsten; Dyndgaard, Morten Glarborg; Andersen, Karin Nordström;

    2003-01-01

    With the recent progress within the field of processing nano structures, there is an increasing interest in coupling light into such structures both for characterization of optical properties and new optical components. In this work we propose the use of a sub-micrometer planar waveguide for prob......With the recent progress within the field of processing nano structures, there is an increasing interest in coupling light into such structures both for characterization of optical properties and new optical components. In this work we propose the use of a sub-micrometer planar waveguide...... for probing the reflection of light against a nano structure. The planar waveguide is based on a silicon nitride core layer, surrounded by a silica cladding region. In our design we utilize this waveguide to couple light into a nano-structure....

  3. Stratified waveguide grating coupler for normal fiber incidence.

    Science.gov (United States)

    Wang, Bin; Jiang, Jianhua; Chambers, Diana M; Cai, Jingbo; Nordin, Gregory P

    2005-04-15

    We propose a new stratified waveguide grating coupler (SWGC) to couple light from a fiber at normal incidence into a planar waveguide. SWGCs are designed to operate in the strong coupling regime without intermediate optics between the fiber and the waveguide. Two-dimensional finite-difference time-domain simulation in conjunction with microgenetic algorithm optimization shows that approximately 72% coupling efficiency is possible for fiber (core size of 8.3 microm and delta=0.36%) to slab waveguide (1.2-microm core and delta=3.1%) coupling. We show that the phase-matching and Bragg conditions are simultaneously satisfied through the fundamental leaky mode.

  4. Plasmonic antennas hybridized with dielectric waveguides.

    Science.gov (United States)

    Bernal Arango, Felipe; Kwadrin, Andrej; Koenderink, A Femius

    2012-11-27

    For the purpose of using plasmonics in an integrated scheme where single emitters can be probed efficiently, we experimentally and theoretically study the scattering properties of single nanorod gold antennas as well as antenna arrays placed on one-dimensional dielectric silicon nitride waveguides. Using real space and Fourier microscopy correlated with waveguide transmission measurements, we quantify the spectral properties, absolute strength, and directivity of scattering. The scattering processes can be well understood in the framework of the physics of dipolar objects placed on a planar layered environment with a waveguiding layer. We use the single plasmonic structures on top of the waveguide as dipolar building blocks for new types of antennas where the waveguide enhances the coupling between antenna elements. We report on waveguide hybridized Yagi-Uda antennas which show directionality in out-coupling of guided modes as well as directionality for in-coupling into the waveguide of localized excitations positioned at the feed element. These measurements together with simulations demonstrate that this system is ideal as a platform for plasmon quantum optics schemes as well as for fluorescence lab-on-chip applications.

  5. Orthogonal and secondary concentration in planar micro-optic solar collectors.

    Science.gov (United States)

    Karp, Jason H; Tremblay, Eric J; Hallas, Justin M; Ford, Joseph E

    2011-07-01

    Planar micro-optic concentrators are passive optical structures which combine a lens array with faceted microstructures to couple sunlight into a planar slab waveguide. Guided rays propagate within the slab to edge-mounted photovoltaic cells. This paper provides analysis and preliminary experiments describing modifications and additions to the geometry which increase concentration ratios along both the vertical and orthogonal waveguide axes. We present simulated results for a 900x concentrator with 85% optical efficiency, measured results for small-scale experimental systems and briefly discuss implementations using low-cost fabrication on continuous planar waveguides.

  6. Leaky mode suppression in planar optical waveguides written in Er:TeO{sub 2}–WO{sub 3} glass and CaF{sub 2} crystal via double energy implantation with MeV N{sup +} ions

    Energy Technology Data Exchange (ETDEWEB)

    Bányász, I., E-mail: banyasz@sunserv.kfki.hu [Department of Crystal Physics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, P.O.B. 49, H-1525 Budapest (Hungary); Zolnai, Z.; Fried, M. [Research Institute for Technical Physics and Materials Science, Research Centre for Natural Sciences, Hungarian Academy of Sciences, P.O.B. 49, Budapest H-1525 (Hungary); Berneschi, S. [MDF-Lab, “Nello Carrara” Institute of Applied Physics, IFAC-CNR, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy); “Enrico Fermi” Center for Study and Research, Piazza del Viminale 2, 00184 Roma (Italy); Pelli, S.; Nunzi-Conti, G. [MDF-Lab, “Nello Carrara” Institute of Applied Physics, IFAC-CNR, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy)

    2014-05-01

    Ion implantation proved to be an universal technique for producing waveguides in most optical materials. Tellurite glasses are good hosts of rare-earth elements for the development of fibre and integrated optical amplifiers and lasers covering all the main telecommunication bands. Er{sup 3+}-doped tellurite glasses are good candidates for the fabrication of broadband amplifiers in wavelength division multiplexing around 1.55 μm, as they exhibit large stimulated cross sections and broad emission bandwidth. Calcium fluoride is an excellent optical material, due to its perfect optical characteristics from UV wavelengths up to near IR. It has become a promising laser host material (doped with rare earth elements). Ion implantation was also applied to optical waveguide fabrication in CaF{sub 2} and other halide crystals. In the present work first single-energy implantations at 3.5 MeV at various fluences were applied. Waveguide operation up to 1.5 μm was observed in Er:Te glass, and up to 980 nm in CaF{sub 2}. Then double-energy implantations at a fixed upper energy of 3.5 MeV and lower energies between 2.5 and 3.2 MeV were performed to suppress leaky modes by increasing barrier width.

  7. Ten inch Planar Optic Display

    Energy Technology Data Exchange (ETDEWEB)

    Beiser, L. [Beiser (Leo) Inc., Flushing, NY (United States); Veligdan, J. [Brookhaven National Lab., Upton, NY (United States)

    1996-04-01

    A Planar Optic Display (POD) is being built and tested for suitability as a high brightness replacement for the cathode ray tube, (CRT). The POD display technology utilizes a laminated optical waveguide structure which allows a projection type of display to be constructed in a thin (I to 2 inch) housing. Inherent in the optical waveguide is a black cladding matrix which gives the display a black appearance leading to very high contrast. A Digital Micromirror Device, (DMD) from Texas Instruments is used to create video images in conjunction with a 100 milliwatt green solid state laser. An anamorphic optical system is used to inject light into the POD to form a stigmatic image. In addition to the design of the POD screen, we discuss: image formation, image projection, and optical design constraints.

  8. Study of silicon strip waveguides with diffraction gratings and photonic crystals tuned to a wavelength of 1.5 µm

    Energy Technology Data Exchange (ETDEWEB)

    Barabanenkov, M. Yu., E-mail: barab@iptm.ru; Vyatkin, A. F.; Volkov, V. T.; Gruzintsev, A. N.; Il’in, A. I.; Trofimov, O. V. [Russian Academy of Sciences, Institute of Microelectronics Technology and High-Purity Materials (Russian Federation)

    2015-12-15

    Single-mode submicrometer-thick strip waveguides on silicon-on-insulator substrates, fabricated by silicon-planar-technology methods are considered. To solve the problem of 1.5-µm wavelength radiation input-output and its frequency filtering, strip diffraction gratings and two-dimensional photonic crystals are integrated into waveguides. The reflection and transmission spectra of gratings and photonic crystals are calculated. The waveguide-mode-attenuation coefficient for a polycrystalline silicon waveguide is experimentally estimated.

  9. Direct milling and casting of polymer-based optical waveguides for improved transparency in the visible range

    DEFF Research Database (Denmark)

    Snakenborg, Detlef; Perozziello, Gerardo; Klank, Henning

    2006-01-01

    with integrated optical waveguides. Polymethylinethacrylate (PMMA) is dissolved in anisole and 'doped' with styrene-arcylonitrile copolymer to vary the refractive index. The doped PMMA with a higher refractive index is then spin coated onto a PMMA substrate with a lower refractive index to provide waveguide...

  10. Biperiodic nanostructured waveguides for wavelength-selectivity of hybrid photonic devices.

    Science.gov (United States)

    Talneau, A; Pommarède, X; Itawi, A; Pantzas, K; Lupu, A; Benisty, H

    2015-11-15

    A biperiodic nanostructuration consisting of a super-periodicity added to a nanohole lattice of subwavelength pitch is demonstrated to provide both modal confinement and wavelength selectivity within a hybrid III-V on a silicon waveguide. The wavelength-selective behavior stems from finely tuned larger holes. Such biperiodic hybrid waveguides have been fabricated by oxide-free bonding III-V material on silicon and display well-defined stop bands. Such nanostructured waveguides offer the versatility for designing advanced optical functions within hybrid devices. Moreover, keeping the silicon waveguide surface planar, such nanostructured waveguides are compatible with electrical operation across the oxide-free hybrid interface.

  11. Polymers in Waveguide Packaging

    Institute of Scientific and Technical Information of China (English)

    Zhiyi Zhang; G. Z.Xiao; Jiaren Liu; C. P. Grover

    2003-01-01

    Polymers were successfully used in the packaging of waveguide-based photonic components in the area of fiber-to-waveguide coupling, waveguide die attachment, strain relief, and waveguide encapsulation. The application results of these polymers were described in this paper.

  12. Ultralow-loss waveguide crossings for the integration of microfluidics and optical waveguide sensors

    Science.gov (United States)

    Wang, Zheng; Yan, Hai; Wang, Zongxing; Zou, Yi; Yang, Chun-Ju; Chakravarty, Swapnajit; Subbaraman, Harish; Tang, Naimei; Xu, Xiaochuan; Fan, D. L.; Wang, Alan X.; Chen, Ray T.

    2015-03-01

    Integrating photonic waveguide sensors with microfluidics is promising in achieving high-sensitivity and cost-effective biological and chemical sensing applications. One challenge in the integration is that an air gap would exist between the microfluidic channel and the photonic waveguide when the micro-channel and the waveguide intersect. The air gap creates a path for the fluid to leak out of the micro-channel. Potential solutions, such as oxide deposition followed by surface planarization, would introduce additional fabrication steps and thus are ineffective in cost. Here we propose a reliable and efficient approach for achieving closed microfluidic channels on a waveguide sensing chip. The core of the employed technique is to add waveguide crossings, i.e., perpendicularly intersecting waveguides, to block the etched trenches and prevent the fluid from leaking through the air gap. The waveguide crossings offer a smooth interface for microfluidic channel bonding while bring negligible additional propagation loss (0.024 dB/crossing based on simulation). They are also efficient in fabrication, which are patterned and fabricated in the same step with waveguides. We experimentally integrated microfluidic channels with photonic crystal (PC) microcavity sensor chips on silicon-on-insulator substrate and demonstrated leak-free sensing measurement with waveguide crossings. The microfluidic channel was made from polydimethylsiloxane (PDMS) and pressure bonded to the silicon chip. The tested flow rates can be varied from 0.2 μL/min to 200 μL/min. Strong resonances from the PC cavity were observed from the transmission spectra. The spectra also show that the waveguide crossings did not induce any significant additional loss or alter the resonances.

  13. Comprehensive FDTD modelling of photonic crystal waveguide components

    DEFF Research Database (Denmark)

    Lavrinenko, Andrei; Borel, Peter Ingo; Frandsen, Lars Hagedorn

    2004-01-01

    Planar photonic crystal waveguide structures have been modelled using the finite-difference-time-domain method and perfectly matched layers have been employed as boundary conditions. Comprehensive numerical calculations have been performed and compared to experimentally obtained transmission...... spectra for various photonic crystal waveguides. It is found that within the experimental fabrication tolerances the calculations correctly predict the measured transmission levels and other major transmission features....

  14. Comprehensive FDTD modelling of photonic crystal waveguide components

    DEFF Research Database (Denmark)

    Lavrinenko, Andrei; Borel, Peter Ingo; Frandsen, Lars Hagedorn;

    2004-01-01

    Planar photonic crystal waveguide structures have been modelled using the finite-difference-time-domain method and perfectly matched layers have been employed as boundary conditions. Comprehensive numerical calculations have been performed and compared to experimentally obtained transmission...... spectra for various photonic crystal waveguides. It is found that within the experimental fabrication tolerances the calculations correctly predict the measured transmission levels and other major transmission features....

  15. Polymer hybrid materials for planar optronic systems

    Science.gov (United States)

    Körner, Martin; Prucker, Oswald; Rühe, Jürgen

    2015-09-01

    Planar optronic systems made entirely from polymeric functional materials on polymeric foils are interesting architectures for monitoring and sensing applications. Key components in this regard are polymer hybrid materials with adjustable optical properties. These materials can then be processed into optical components such as waveguides for example by using embossing techniques. However, the resulting microstructures have often low mechanical or thermal stability which quickly leads to a degradation of the microstructures accompanied often by a complete loss of function. A simple and versatile way to increase the thermal and mechanical stability of polymers is to connect the individual chains to a polymer network by using thermally or photochemically reactive groups. Upon excitation, these groups form reactive intermediates such as radicals or nitrenes which then crosslink with adjacent C-H-groups through a C,H insertion reaction (CHic = C,H insertion based crosslinking). To generate waveguide structures a PDMS stamp is filled with the waveguide core material e.g. poly(methylmethacrylate) (PMMA), which is modified with a few mol% of the thermal crosslinker and hot embossed onto a foil substrate e.g. PMMA. In this one-step hot embossing process polymer ridge waveguides are formed and simultaneously the polymer becomes crosslinked. Due to the reaction across the boundary between waveguide and substrate it is also possible to combine initially incompatible polymers for the waveguide and the substrate foil. The thermomechanical properties of the obtained materials are studied.

  16. Integrated Planar Lightwave Circuits for UV Generation and Phase Modulation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR Phase I effort proposes to establish the feasibility of developing a UV Planar Lightwave Circuit (PLC); a compact, highly efficient, waveguide-based...

  17. Dielectric THz waveguides

    Science.gov (United States)

    Dupuis, Alexandre

    . By translating the coupling probe fiber along the length of the sample the propagation loss could be estimated in a non-destructive way. Because of the low-pass frequency filtering of the probe fiber and the frequency integration of the detector, the results required careful interpretation and spectral information was limited to the vicinity of 0.2 THz. Subsequent transmission experiments using the adjustable THz-TDS setup enabled the measurement of the full loss spectrum and confirmed the very low propagation loss (< 0.02 cm-1) of the porous subwavelength fibers, among some of the lowest reported losses to date. These measurements further demonstrated that the addition of porosity blue-shifted absorption losses, by virtue of increasing the fraction of power guided in air, thus enabling transmission at higher frequencies and with a wider transmission peak than non-porous subwavelength fibers. Much effort was also spent on exploring the hollow-core waveguide strategy with the development of large hollow-core Bragg fibers. Owing to the similarities in the refractive indices of polymers in the THz regime, two different methods were proposed and implemented for increasing the refractive index contrast between the layers of the Bragg reflector. The first method consisted of co-rolling a polymer film with powder particles in order to create air layers. The second method consisted in rolling a bi-layer of a TiO2 doped polyethylene film and a pure polyethylene film. Despite the increased index contrast between the doped and undoped layers, the overall propagation loss was larger than that of the air-polymer Bragg fiber due to the high absorption loss of the TiO2 doped film. Although much prior work had been done by others on planar THz Bragg reflectors this is the first implementation of a THz Bragg fiber. Unfortunately, in their current implementation the fibers are either too lossy or mechanically unstable. (Abstract shortened by UMI.)

  18. Quantum waveguides

    CERN Document Server

    Exner, Pavel

    2015-01-01

    This monograph explains the theory of quantum waveguides, that is, dynamics of quantum particles confined to regions in the form of tubes, layers, networks, etc. The focus is on relations between the confinement geometry on the one hand and the spectral and scattering properties of the corresponding quantum Hamiltonians on the other. Perturbations of such operators, in particular, by external fields are also considered. The volume provides a unique summary of twenty five years of research activity in this area and indicates ways in which the theory can develop further. The book is fairly self-contained. While it requires some broader mathematical physics background, all the basic concepts are properly explained and proofs of most theorems are given in detail, so there is no need for additional sources. Without a parallel in the literature, the monograph by Exner and Kovarik guides the reader through this new and exciting field.

  19. Proton-exchanged LiNbO(3) waveguides: relevance of atmospheric environment during annealing.

    Science.gov (United States)

    Loni, A; De La Rue, R M

    1992-08-20

    The relevance of the type of atmosphere used during the annealing of proton-exchanged LiNbO(3) planar waveguides is discussed. The experimental evidence, based on a comparison of the refractive-index profiles of waveguides annealed under wet O(2), dry O(2), or ambient atmospheres, with various gas flow rates, suggests that the atmosphere type does not influence the properties of the resulting waveguide.

  20. InGaAsP Buried Channel Waveguide For Electroabsorption Modulation

    Science.gov (United States)

    Lin, S. C.; Chin, M. K.; Jing, X. L.; Walpita, L. M.; Yu, P. K. L.; Chang, W. S.

    1987-11-01

    External modulation of 1.3 μm laser light with LPE grown InGaAsP/InP buried channel waveguides is presented. The waveguide is compatible with single mode fiber and the planar structure has potential for monolithic integration. In this paper, a numerical analysis of electroabsorption (EA) modulation for the waveguide modulator shows interesting results which may help the design of this device.

  1. Spatial solitons in nonlinear liquid waveguides

    Indian Academy of Sciences (India)

    R Barillé; G Rivoire

    2001-11-01

    Spatial solitons are studied in a planar waveguide filled with nonlinear liquids. Spectral and spatial measurements for different geometries and input power of the laser beam show the influence of different nonlinear effects as stimulated scatterings on the soliton propagation and in particular on the beam polarization. The stimulated scattering can be used advantageously to couple the two polarization components. This effect can lead to multiple applications in optical switching.

  2. High slope efficiency and low threshold in a laser-diode-pumped passively Q-switched ion-implanted Nd:YVO4 planar waveguide laser with GaAs saturable absorber

    Science.gov (United States)

    Du, G. L.; Li, G. Q.; Zhao, S. Z.; Li, T.; Yang, K. J.; Li, X.

    2011-11-01

    A passively Q-switched waveguide laser, to our knowledge, has been firstly demonstrated in Nd: YVO4 crystal formed by 3 MeV Si+ ion implantation at a dose of 1 × 1015 ions/cm2 at room temperature, in which GaAs was used as saturable absorber. The dependences of the average output power, pulse width, pulse repetition rate on absorbed pump power have been measured at different output plane mirror transmissions. At an absorbed pump power of 78.8 mW and output transmission of 20%, the shortest pulse width of 3.88 ns was obtained, corresponding to the peak power and single pulse energy of 212 W and 0.82 μJ, respectively. The threshold pump power was as low as 40 mW, and the slope efficiency was about 64.5% when the absorbed pump power was lower than 70 mW.

  3. Coupling ideality of integrated planar high-Q microresonators

    CERN Document Server

    Pfeiffer, Martin H P; Geiselmann, Michael; Kippenberg, Tobias J

    2016-01-01

    Chipscale microresonators with integrated planar optical waveguides are useful building blocks for linear, nonlinear and quantum optical devices. Loss reduction through improving fabrication processes has resulted in several integrated micro resonator platforms attaining quality (Q) factors of several millions. However only few studies have investigated design-dependent losses, especially with regard to the resonator coupling section. Here we investigate design-dependent parasitic losses, described by the coupling ideality, of the commonly employed microresonator design consisting of a microring resonator waveguide side-coupled to a straight bus waveguide. By systematic characterization of multi-mode high-Q silicon nitride microresonator devices, we show that this design can suffer from low coupling ideality. By performing full 3D simulations to numerically investigate the resonator to bus waveguide coupling, we identify the coupling to higher-order bus waveguide modes as the dominant origin of parasitic loss...

  4. Compact waveguide circular polarizer

    Science.gov (United States)

    Tantawi, Sami G.

    2016-08-16

    A multi-port waveguide is provided having a rectangular waveguide that includes a Y-shape structure with first top arm having a first rectangular waveguide port, a second top arm with second rectangular waveguide port, and a base arm with a third rectangular waveguide port for supporting a TE.sub.10 mode and a TE.sub.20 mode, where the end of the third rectangular waveguide port includes rounded edges that are parallel to a z-axis of the waveguide, a circular waveguide having a circular waveguide port for supporting a left hand and a right hand circular polarization TE.sub.11 mode and is coupled to a base arm broad wall, and a matching feature disposed on the base arm broad wall opposite of the circular waveguide for terminating the third rectangular waveguide port, where the first rectangular waveguide port, the second rectangular waveguide port and the circular waveguide port are capable of supporting 4-modes of operation.

  5. Chalcogenide Glass Optical Waveguides for Infrared Biosensing

    Science.gov (United States)

    Anne, Marie-Laure; Keirsse, Julie; Nazabal, Virginie; Hyodo, Koji; Inoue, Satoru; Boussard-Pledel, Catherine; Lhermite, Hervé; Charrier, Joël; Yanakata, Kiyoyuki; Loreal, Olivier; Le Person, Jenny; Colas, Florent; Compère, Chantal; Bureau, Bruno

    2009-01-01

    Due to the remarkable properties of chalcogenide (Chg) glasses, Chg optical waveguides should play a significant role in the development of optical biosensors. This paper describes the fabrication and properties of chalcogenide fibres and planar waveguides. Using optical fibre transparent in the mid-infrared spectral range we have developed a biosensor that can collect information on whole metabolism alterations, rapidly and in situ. Thanks to this sensor it is possible to collect infrared spectra by remote spectroscopy, by simple contact with the sample. In this way, we tried to determine spectral modifications due, on the one hand, to cerebral metabolism alterations caused by a transient focal ischemia in the rat brain and, in the other hand, starvation in the mouse liver. We also applied a microdialysis method, a well known technique for in vivo brain metabolism studies, as reference. In the field of integrated microsensors, reactive ion etching was used to pattern rib waveguides between 2 and 300 μm wide. This technique was used to fabricate Y optical junctions for optical interconnections on chalcogenide amorphous films, which can potentially increase the sensitivity and stability of an optical micro-sensor. The first tests were also carried out to functionalise the Chg planar waveguides with the aim of using them as (bio)sensors. PMID:22423209

  6. Cladding-like waveguide structure in Nd:YAG crystal fabricated by multiple ion irradiation for enhanced waveguide lasing.

    Science.gov (United States)

    Shang, Zhen; Tan, Yang; Akhmadaliev, Shavkat; Zhou, Shengqiang; Chen, Feng

    2015-10-19

    We report on a cladding-like waveguide structure in Nd:YAG crystal fabricated by the multiple carbon ion beam irradiation. After the designed multiple irradiation process, the cladding-like waveguide with triple refractive-index layers were constructed in the region near the surface of the crystal. With such a structure, the waveguiding core was compressed and refractive index profile was modified, resulting in a higher light intensity than that of the single ion-beam-irradiated monolayer waveguide. The waveguide lasing at wavelength of 1064 nm was achieved with enhanced performance in the cladding-like structures with both planar and ridge configurations by the optical pump at 810 nm.

  7. Multimode waveguide speckle patterns for compressive sensing.

    Science.gov (United States)

    Valley, George C; Sefler, George A; Justin Shaw, T

    2016-06-01

    Compressive sensing (CS) of sparse gigahertz-band RF signals using microwave photonics may achieve better performances with smaller size, weight, and power than electronic CS or conventional Nyquist rate sampling. The critical element in a CS system is the device that produces the CS measurement matrix (MM). We show that passive speckle patterns in multimode waveguides potentially provide excellent MMs for CS. We measure and calculate the MM for a multimode fiber and perform simulations using this MM in a CS system. We show that the speckle MM exhibits the sharp phase transition and coherence properties needed for CS and that these properties are similar to those of a sub-Gaussian MM with the same mean and standard deviation. We calculate the MM for a multimode planar waveguide and find dimensions of the planar guide that give a speckle MM with a performance similar to that of the multimode fiber. The CS simulations show that all measured and calculated speckle MMs exhibit a robust performance with equal amplitude signals that are sparse in time, in frequency, and in wavelets (Haar wavelet transform). The planar waveguide results indicate a path to a microwave photonic integrated circuit for measuring sparse gigahertz-band RF signals using CS.

  8. Synthesis and Characterization of Quinoxaline-Based Low-Bandgap Copolymers for Bulk Heterojunction Solar Cells

    Science.gov (United States)

    Lee, Yoonkyoo; Jo, Won Ho

    2011-03-01

    A series of low-bandgap alternating copolymers consisting of quinoxaline derivatives and electron-donating carbazole or fluorene were synthesized via the Suzuki coupling reaction. For the purpose to improve the molecular packing of polymer chains and to enhance the charge carrier mobility in the packing direction, a new quinoxaline derivative, 5,8-dithien-2-yl-dibenzophenazine which has perfectly planar polycyclic structure, was synthesized and introduced as a new building block for alternating copolymers instead of frequently-used 5,8-dithien-2-yl-2,3-diphenylquinoxaline. The use of planar quinoxaline derivative exhibited better optical, electrochemical, and structural properties of the resulting copolymers as compared to those of polymers with less planar quinoxaline derivatives. Charge transport and photovoltaic properties of these two classes of copolymers are compared and discussed.

  9. Thermo-optic Goos-Hänchen effect in silicon-on-insulator waveguide

    Science.gov (United States)

    Tang, Tingting; Luo, Li; Liu, Wenli; He, Xiujun; Zhang, Yanfen

    2015-09-01

    We study the thermo-optic Goos-Hänchen (TOGH) effect in a prism-waveguide coupling structure with silicon-on-insulator waveguide. Stationary-phase method is utilized to calculate the TOGH shift. When the waveguide is regarded as a two-dimensional planar waveguide, a nonlinear relation between GH shift and temperature is obtained. Based on the noticeable TOGH effect, a sensitive temperature modulator or sensor can be realized. As the waveguide width is limited, the proposed structure can be regarded as a three-dimensional rectangular waveguide. We explore the GH shift and TOGH effect for different modes propagating in rectangular waveguide which show different linear relations between GH shift and temperature, which can be used to design mode-selective device based on TO effect.

  10. Waveguide cooling system

    Science.gov (United States)

    Chen, B. C. J.; Hartop, R. W.

    1981-04-01

    An improved system is described for cooling high power waveguides by the use of cooling ducts extending along the waveguide, which minimizes hot spots at the flanges where waveguide sections are connected together. The cooling duct extends along substantially the full length of the waveguide section, and each flange at the end of the section has a through hole with an inner end connected to the duct and an opposite end that can be aligned with a flange hole in another waveguide section. Earth flange is formed with a drainage groove in its face, between the through hole and the waveguide conduit to prevent leakage of cooling fluid into the waveguide. The ducts have narrowed sections immediately adjacent to the flanges to provide room for the installation of fasteners closely around the waveguide channel.

  11. Microfabricated Waveguide Atom Traps.

    Energy Technology Data Exchange (ETDEWEB)

    Jau, Yuan-Yu

    2017-09-01

    A nano - scale , microfabricated waveguide structure can in - principle be used to trap atoms in well - defined locations and enable strong photon - atom interactions . A neutral - atom platf orm based on this microfabrication technology will be pre - aligned , which is especially important for quantum - control applications. At present, there is still no reported demonstration of evanescent - field atom trapping using a microfabricated waveguide structure. We described the capabilities established by our team for future development of the waveguide atom - trapping technology at SNL and report our studies to overcome the technical challenges of loading cold atoms into the waveguide atom traps, efficient and broadband optical coupling to a waveguide, and the waveguide material for high - power optical transmission. From the atomic - physics and the waveguide modeling, w e have shown that a square nano - waveguide can be utilized t o achieve better atomic spin squeezing than using a nanofiber for first time.

  12. Second-order optical nonlinearities in dilute melt proton exchange waveguides in z-cut LiNbO3

    DEFF Research Database (Denmark)

    Veng, Torben Erik; Skettrup, Torben; Pedersen, Kjeld

    1996-01-01

    Planar optical waveguides with different refractive indices are made in z-cut LiNbO3 with a dilute proton exchange method using a system of glycerol containing KHSO4 and lithium benzoate. The optical second-order susceptibilities of these waveguides are measured by detecting the 266 nm reflected...... second-harmonic signal generated by a 532 nm beam directed onto the waveguide surface. It is found for this kind of waveguides that in the waveguide region all the second-order susceptibilities take values of at least 90% of the original LiNbO; values for refractive index changes less than similar to 0...

  13. Optimization and applications of planar silicon-based photonic crystal devices

    DEFF Research Database (Denmark)

    Borel, Peter Ingo; Frandsen, Lars Hagedorn; Burgos Leon, Juan;

    2005-01-01

    such as topology optimization. We have also investigated a new device concept for coarse wavelength division de-multiplexing based on planar photonic crystal waveguides. The filtering of the wavelength channels has been realized by shifting the cut-off frequency of the fundamental photonic band gap mode......Very low propagation losses in straight planar photonic crystal waveguides have previously been reported. A next natural step is to add functionality to the photonic crystal waveguides and create ultra compact optical components. We have designed and fabricated such structures in a silicon......-on-insulator material. The photonic crystal is defined by holes with diameter 250 nm arranged in a triangular lattice having lattice constant 400 nm. Leaving out single rows of holes creates the planar photonic crystal waveguides. Different types of couplers and splitters, aswell as 60. 90 and 120 degree bends have...

  14. Recent progress on planar lightwave circuit technology for optical communication

    Science.gov (United States)

    Takahashi, Hiroshi

    2009-11-01

    Silica waveguide planar lightwave circuit (PLC) technology is very useful for fabricating compact and high performance optical devices for optical communication. Wavelength multiplexers and optical switches for ROADM and OXC are still being developed to improve performance further. New devices for an advanced modulation format can also be fabricated with PLC technology.

  15. UV writing of advanced Bragg gratings in optical waveguides

    DEFF Research Database (Denmark)

    Jensen, Jesper Bo Damm

    2002-01-01

    The subject of this ph.d. thesis is the fabrication of Bragg gratings in optical waveguides. During the study Bragg gratings were written in both planar waveguides and optical fibers using pulsed or continuous-wave lasers operating in the ultraviolet (UV) range. The main result is the development...... of the novel polarization control method for UV writing of Bragg gratings with advanced apodization profiles including phase shifts. The principle of the polarization control method relies on a spatial separation of the s- and p-polarized components of a linearly polarized UV beam corresponding to half...... were then translated into a polarizer angle profile and the Bragg grating were written using a pulsed excimer laser. Only optical fibers were used in this part of the thesis. The high quality planar waveguides used during the study were produced in the cleanroom facility at the Microelectronic Center...

  16. Polymer waveguide grating sensor integrated with a thin-film photodetector.

    Science.gov (United States)

    Song, Fuchuan; Xiao, Jing; Xie, Antonio Jou; Seo, Sang-Woo

    2014-01-01

    This paper presents a planar waveguide grating sensor integrated with a photodetector (PD) for on-chip optical sensing systems which are suitable for diagnostics in the field and in-situ measurements. III-V semiconductor-based thin-film PD is integrated with a polymer based waveguide grating device on a silicon platform. The fabricated optical sensor successfully discriminates optical spectral characteristics of the polymer waveguide grating from the on-chip PD. In addition, its potential use as a refractive index sensor is demonstrated. Based on a planar waveguide structure, the demonstrated sensor chip may incorporate multiple grating waveguide sensing regions with their own optical detection PDs. In addition, the demonstrated processing is based on a post-integration process which is compatible with silicon complementary metal-oxide semiconductor (CMOS) electronics. Potentially, this leads a compact, chip-scale optical sensing system which can monitor multiple physical parameters simultaneously without need for external signal processing.

  17. DESIGN OF V-BAND SUBSTRATE INTEGRATED WAVEGUIDE POWER DIVIDER, CIRCULATOR AND COUPLER

    Directory of Open Access Journals (Sweden)

    Bouchra Rahali

    2013-11-01

    Full Text Available Recently there is growing interest in a new technology, substrate integrated waveguide (SIW, it has been applied successfully to the conception of planar compact components for the microwave and millimeter waves applications. In this study, a V-band substrate integrated waveguide power divider, circulator and coupler are conceived and optimized by Ansoft HFSS code. Thus, through this modeling, design considerations and results are discussed and presented. Attractive features including compact size and planar form make these devices structure easily integrated in planar circuits.

  18. BaTiO3 waveguide self-pumped phase conjugator

    OpenAIRE

    James, S. W.; Youden, K.E.; Jeffrey, P. M.; EASON, R. W.; Chandler, P.J.; Zhang, L.; Townsend, P.D.

    1993-01-01

    For the first time to our knowledge, self-pumped phase conjugation is reported in a planar waveguide structure in a BaTiO3 single crystal. The waveguide was fabricated by the technique of ion implantation, with 1.5-MeV H+ ions at a dose of 10^16 ions/cm^2. Phase-conjugate reflectivities >20% have been measured for waveguide self-pumped phase conjugation, and, for a given input power, an order-of-magnitude reduction in the response time is observed in the waveguide compared with the bulk. The ...

  19. Monolithic integration of microfluidic channels and optical waveguides in silica on silicon

    DEFF Research Database (Denmark)

    Friis, Peter; Hoppe, Karsten; Leistiko, Otto

    2001-01-01

    Sealing of the flow channel is an important aspect during integration of microfluidic channels and optical waveguides. The uneven topography of many waveguide-fabrication techniques will lead to leakage of the fluid channels. Planarization methods such as chemical mechanical polishing or the etch......-back technique are possible, but troublesome. We present a simple but efficient alternative: By means of changing the waveguide layout, bonding pads are formed along the microfluidic channels. With the same height as the waveguide, they effectively prevent leakage and hermetically seal the channels during...

  20. Compressive and tensile strain sensing using a polymer planar Bragg grating.

    Science.gov (United States)

    Rosenberger, M; Hessler, S; Belle, S; Schmauss, B; Hellmann, R

    2014-03-10

    A polymer planar Bragg grating sensor is used for measuring both mechanical compressive and tensile strain. The planar waveguide with integrated Bragg grating is fabricated in bulk Polymethylmethacrylate in a single writing step using combined amplitude and phase mask technique. After butt coupling of a single-mode optical fiber the planar structure can be applied for measuring both mechanical tensile and compressive strain alongside the integrated waveguide without the need of further modifications. In this respect, we particularly report for the first time compressive strain measurements using a polymer Bragg grating. Furthermore, the sensitivity of the sensor against tensile and compressive strain, its reproducibility and hysteresis are investigated and discussed.

  1. Perturbations of planar algebras

    CERN Document Server

    Das, Paramita; Gupta, Ved Prakash

    2010-01-01

    We introduce the concept of {\\em weight} of a planar algebra $P$ and construct a new planar algebra referred as the {\\em perturbation of $P$} by the weight. We establish a one-to-one correspondence between pivotal structures on 2-categories and perturbations of planar algebras by weights. To each bifinite bimodule over $II_1$-factors, we associate a {\\em bimodule planar algebra} bimodule corresponds naturally with sphericality of the bimodule planar algebra. As a consequence of this, we reproduce an extension of Jones' theorem (of associating 'subfactor planar algebras' to extremal subfactors). Conversely, given a bimodule planar algebra, we construct a bifinite bimodule whose associated bimodule planar algebra is the one which we start with using perturbations and Jones-Walker-Shlyakhtenko-Kodiyalam-Sunder method of reconstructing an extremal subfactor from a subfactor planar algebra. We show that the perturbation class of a bimodule planar algebra contains a unique spherical unimodular bimodule planar algeb...

  2. Fabrication of ridge waveguides: a new solgel route.

    Science.gov (United States)

    Fardad, A; Andrews, M; Milova, G; Malek-Tabrizi, A; Najafi, I

    1998-04-20

    Passive ridge waveguides can be deposited on silicon by a solvent-assisted lithographic process incorporating simple mask technology and photosensitive solgel-derived glasses. Thick films (~4 mum) are dip coated in one step, and channel waveguides and power splitters are imprinted in them by UV light through appropriate masks. Unexposed regions of the glass are removed by soaking of the films in n-propanol. The remaining ridges are then treated at 200 degrees C and planarized with a solgel cladding layer. Circular mode profiles are observed from ridge guides covered with the cladding. The waveguides are characterized with scanning electron microscopy, atomic force microscopy, surface profilometry, ellipsometry, and fiber end coupling. Overall, the procedure is simple and reproducible and leads to waveguides with low loss, of the order of 0.13 dB/cm.

  3. Broadband single-transverse-mode fluorescence sources based on ribs fabricated in pulsed laser deposited Ti: sapphire waveguides

    NARCIS (Netherlands)

    Grivas, C.; May-Smith, T.C.; Shepherd, D.P.; Eason, R.W.; Pollnau, M.; Jelinek, M.

    2004-01-01

    Active rib waveguides with depths and widths varying from 3 to 5 μm and from 9 to 24 μm, respectively, have been structured by $Ar^{+}$-beam etching in pulsed laser deposited Ti:sapphire layers. Losses in the channel structures were essentially at the same levels as the unstructured planar waveguide

  4. Ti:sapphire rib waveguides as single-transverse-mode broadband fluorescence sources for optical coherence tomography applications

    NARCIS (Netherlands)

    Grivas, C.; Shepherd, D.P.; May-Smith, T.C.; Eason, R.W.; Pollnau, M.; Crunteanu, A.; Jelinek, M.

    2003-01-01

    Ar+-beam-milled rib waveguides in pulsed-laser-deposited Ti:sapphire layers show broadband single transverse mode fluorescence emission at output powers up to 300 μW and propagation losses comparable to those in unstructured planar waveguide counterparts.

  5. Ridge Waveguide Structures in Magnesium-Doped Lithium Niobate

    Science.gov (United States)

    Himmer, Phillip; Battle, Philip; Suckow, William; Switzer, Greg

    2011-01-01

    This work proposes to establish the feasibility of fabricating isolated ridge waveguides in 5% MgO:LN. Ridge waveguides in MgO:LN will significantly improve power handling and conversion efficiency, increase photonic component integration, and be well suited to spacebased applications. The key innovation in this effort is to combine recently available large, high-photorefractive-damage-threshold, z-cut 5% MgO:LN with novel ridge fabrication techniques to achieve high-optical power, low-cost, high-volume manufacturing of frequency conversion structures. The proposed ridge waveguide structure should maintain the characteristics of the periodically poled bulk substrate, allowing for the efficient frequency conversion typical of waveguides and the high optical damage threshold and long lifetimes typical of the 5% doped bulk substrate. The low cost and large area of 5% MgO:LN wafers, and the improved performance of the proposed ridge waveguide structure, will enhance existing measurement capabilities as well as reduce the resources required to achieve high-performance specifications. The purpose of the ridge waveguides in MgO:LN is to provide platform technology that will improve optical power handling and conversion efficiency compared to existing waveguide technology. The proposed ridge waveguide is produced using standard microfabrication techniques. The approach is enabled by recent advances in inductively coupled plasma etchers and chemical mechanical planarization techniques. In conjunction with wafer bonding, this fabrication methodology can be used to create arbitrarily shaped waveguides allowing complex optical circuits to be engineered in nonlinear optical materials such as magnesium doped lithium niobate. Researchers here have identified NLO (nonlinear optical) ridge waveguide structures as having suitable value to be the leading frequency conversion structures. Its value is based on having the low-cost fabrication necessary to satisfy the challenging pricing

  6. Graphene antidot lattice waveguides

    DEFF Research Database (Denmark)

    Pedersen, Jesper Goor; Gunst, Tue; Markussen, Troels

    2012-01-01

    We introduce graphene antidot lattice waveguides: nanostructured graphene where a region of pristine graphene is sandwiched between regions of graphene antidot lattices. The band gaps in the surrounding antidot lattices enable localized states to emerge in the central waveguide region. We model...... the waveguides via a position-dependent mass term in the Dirac approximation of graphene and arrive at analytical results for the dispersion relation and spinor eigenstates of the localized waveguide modes. To include atomistic details we also use a tight-binding model, which is in excellent agreement...... with the analytical results. The waveguides resemble graphene nanoribbons, but without the particular properties of ribbons that emerge due to the details of the edge. We show that electrons can be guided through kinks without additional resistance and that transport through the waveguides is robust against...

  7. Silicon containing copolymers

    CERN Document Server

    Amiri, Sahar; Amiri, Sanam

    2014-01-01

    Silicones have unique properties including thermal oxidative stability, low temperature flow, high compressibility, low surface tension, hydrophobicity and electric properties. These special properties have encouraged the exploration of alternative synthetic routes of well defined controlled microstructures of silicone copolymers, the subject of this Springer Brief. The authors explore the synthesis and characterization of notable block copolymers. Recent advances in controlled radical polymerization techniques leading to the facile synthesis of well-defined silicon based thermo reversible block copolymers?are described along with atom transfer radical polymerization (ATRP), a technique utilized to develop well-defined functional thermo reversible block copolymers. The brief also focuses on Polyrotaxanes and their great potential as stimulus-responsive materials which produce poly (dimethyl siloxane) (PDMS) based thermo reversible block copolymers.

  8. MPACVD processing technologies for planar integrated optics

    Science.gov (United States)

    Li, Cheng-Chung; Boudreau, Robert A.; Bowen, Terry P.

    1998-06-01

    Optical circuits based on low-loss glass waveguide are the practical and promising approaches to integrate different functional components for optical communication system. Microwave plasma assisted chemical vapor deposition produces superior quality, low birefringence, low-loss, planar waveguides for integrated optical devices. A microwave plasma initiates the chemical vapor of SiCl4, GeCl4 and oxygen. A Ge-doped silica layer thus deposited on the substrates with reasonable high growth rate. Film properties are based on various parameters, such as chemical flow rates, chamber pressure and temperature, power level and injector design. The main emphasis has been on optimizing the deposition parameters and reproducibility. An uniform, low-loss film can be made by properly balancing the precursor flows. The refractive index of deposited film can also be controlled by adjusting the flow ratio of SiCl4 and GeCl4 bubblers. Deposited films was characterized by prism coupler, loss measurement, residual stress, and composition analysis. The resulted refractive index step can be varied between 1.46 to 1.60. Waveguide can be fabricated with any desired refractive index profile. Standard photolithography defines the waveguide pattern on mask layer. Core layer was remove by the plasma dry etch which has been investigated by both reactive ion etch (RIE) and inductively coupled plasma etch. Etch rate of 3000-4000 angstrom/min has been achieved by using ICP compared to typical etch rate of 200-300 angstrom/min by using conventional RIE.

  9. Waveguide arrangements based on adiabatic elimination

    Energy Technology Data Exchange (ETDEWEB)

    Suchowski, Haim; Mrejen, Michael; Wu, Chihhui; Zhang, Xiang

    2016-09-13

    This disclosure provides systems, methods, and apparatus related to nanophotonics. In one aspect, an arrangement of waveguides includes a substrate and three waveguides. Each of the three waveguides may be a linear waveguide. A second waveguide is positioned between a first waveguide and a third waveguide. The dimensions and positions of the first, the second, and the third waveguides are specified to substantially eliminate coupling between the first waveguide and the third waveguide over a distance of about 1 millimeter to 2 millimeters along lengths of the first waveguide, the second waveguide, and the third waveguide.

  10. Quantitative study of rectangular waveguide behavior in the THz.

    Energy Technology Data Exchange (ETDEWEB)

    Rowen, Adam M.; Nordquist, Christopher Daniel; Wanke, Michael Clement

    2009-10-01

    This report describes our efforts to quantify the behavior of micro-fabricated THz rectangular waveguides on a configurable, robust semiconductor-based platform. These waveguides are an enabling technology for coupling THz radiation directly from or to lasers, mixers, detectors, antennas, and other devices. Traditional waveguides fabricated on semiconductor platforms such as dielectric guides in the infrared or co-planar waveguides in the microwave regions, suffer high absorption and radiative losses in the THz. The former leads to very short propagation lengths, while the latter will lead to unwanted radiation modes and/or crosstalk in integrated devices. This project exploited the initial developments of THz micro-machined rectangular waveguides developed under the THz Grand Challenge Program, but instead of focusing on THz transceiver integration, this project focused on exploring the propagation loss and far-field radiation patterns of the waveguides. During the 9 month duration of this project we were able to reproduce the waveguide loss per unit of length in the waveguides and started to explore how the loss depended on wavelength. We also explored the far-field beam patterns emitted by H-plane horn antennas attached to the waveguides. In the process we learned that the method of measuring the beam patterns has a significant impact on what is actually measured, and this may have an effect on most of the beam patterns of THz that have been reported to date. The beam pattern measurements improved significantly throughout the project, but more refinements of the measurement are required before a definitive determination of the beam-pattern can be made.

  11. Simulation and measurement of slow light in photonic crystal waveguides

    DEFF Research Database (Denmark)

    Lavrinenko, Andrei; Jacobsen, Rune Shim; Fage-Pedersen, Jacob

    Planar photonic crystals offer a fascinating means of manipulation of light in integrated,optical circuits. Such waveguides can be realized, as in the present investigations, byfabricating arrays of holes with sub-micrometer distance in the top layer of a silicon-oninsulatorwafer. The waveguides...... can be tailored such that the propagating mode achievesextreme dispersion as well as a low group velocity, allowing for realization of ultracompact, functional devices. Here, we present numerical modeling and measurements ofthe time-of-flight propagation of optical pulses. Near the cut...

  12. Power-transfer effects in monomode optical nonlinear waveguiding structures.

    Science.gov (United States)

    Jakubczyk, Z; Jerominek, H; Patela, S; Tremblay, R; Delisle, C

    1987-09-01

    We describe power-transfer effects, over a certain threshold, among constituents of planar waveguiding structures consisting of an optical linear layer deposited onto a nonlinear substrate (CdS(x)Se(1-x)-doped glass). Proper selection of the thickness of the linear waveguiding film and the refractive index of the linear cladding allows one to obtain optical transistor action and to construct all-optical AND, OR, NOT, and XOR logic gates. The effects appear for the TE(0) guided mode.

  13. Cascaded third harmonic generation in hybrid graphene-semiconductor waveguides

    CERN Document Server

    Smirnova, Daria A

    2015-01-01

    We study cascaded harmonic generation of hybrid surface plasmons in integrated planar waveguides composed of a graphene layer and a doped-semiconductor slab. We derive a comprehensive model of cascaded third harmonic generation through phase-matched nonlinear interaction of fundamental, second harmonic and third harmonic plasmonic modes supported by the structure. We show that hybrid graphene-semiconductor waveguides can simultaneously phase-match these three interacting harmonics, increasing the total third-harmonic output by a factor of 5 compared to the non-cascaded regime.

  14. Simulation and measurement of slow light in photonic crystal waveguides

    DEFF Research Database (Denmark)

    Lavrinenko, Andrei; Jacobsen, Rune Shim; Fage-Pedersen, Jacob;

    Planar photonic crystals offer a fascinating means of manipulation of light in integrated,optical circuits. Such waveguides can be realized, as in the present investigations, byfabricating arrays of holes with sub-micrometer distance in the top layer of a silicon-oninsulatorwafer. The waveguides...... can be tailored such that the propagating mode achievesextreme dispersion as well as a low group velocity, allowing for realization of ultracompact, functional devices. Here, we present numerical modeling and measurements ofthe time-of-flight propagation of optical pulses. Near the cut...

  15. Practical implementation of a planar micro-optic solar concentrator

    Science.gov (United States)

    Baker, Katherine; Karp, Jason; Hallas, Justin; Ford, Joseph

    2012-10-01

    CPV optics typically have multiple discrete apertures which each focus sunlight directly onto an associated PV cell. Waveguide based CPV systems instead couple light from multiple small apertures through a shared slab waveguide, avoiding individual optical alignment and electrical connection of multiple PV cells. We previously demonstrated the design and fabrication of a planar micro-optic waveguide concentrator, where incoming sunlight is focused through millimeter pitch lenslets onto mirrored micro-prisms which couple light into a slab waveguide toward common PV cells. This enables an efficient high concentrator system with a compact geometry. However, this design has the typical CPV limitation of low angular acceptance, requiring precise two-axis large-scale mechanical tracking. Here, we present the results of a design study to adapt the planar micro-optic design for use in combination with a one-dimensional mechanical tracker, tilted at latitude, to provide azimuthal alignment and altitude bias. Lateral mechanical micro-tracking can accommodate the residual altitude misalignment. The design shows that this relatively simple system can still provide over 72% annual optical efficiency for a 50x concentrator. Replacing the micro-tracking with passive optical altitude alignment further reduces system complexity, but also reduces efficiency. These waveguide based concentrators have primarily been designed for use with photovoltaic cells, which are index matched onto the waveguide either directly, or through output couplers. For concentrating solar power systems, sunlight is focused onto thermally isolated devices which can not be in direct contact. We will also present alternative output coupler designs, which allow extraction of light from the waveguide to an air or vacuum isolated coupler. The loss associated with these couplers is substantially identical to the reflection losses of one additional mirror.

  16. Optical waveguides in magneto-optical glasses fabricated by proton implantation

    Science.gov (United States)

    Liu, Chun-Xiao; Li, Yu-Wen; Zheng, Rui-Lin; Fu, Li-Li; Zhang, Liao-Lin; Guo, Hai-Tao; Zhou, Zhi-Guang; Li, Wei-Nan; Lin, She-Bao; Wei, Wei

    2016-11-01

    Planar waveguides in magneto-optical glasses (Tb3+-doped aluminum borosilicate glasses) have been produced by a 550-keV proton implantation at a dose of 4.0×1016 ions/cm2 for the first time to our knowledge. After annealing at 260 °C for 1.0 h, the dark-mode spectra and near-field intensity distributions are measured by the prism-coupling and end-face coupling methods. The damage profile, refractive index distribution and light propagation mode of the planar waveguide are numerically calculated by SRIM 2010, RCM and FD-BPM, respectively. The effects of implantation on the structural and optical properties are investigated by Raman and absorption spectra. It suggests that the proton-implanted Tb3+-doped aluminum borosilicate glass waveguide is a good candidate for a waveguide isolator in optical fiber communication and all-optical communication.

  17. Exact equivalent straight waveguide model for bent and twisted waveguides

    DEFF Research Database (Denmark)

    Shyroki, Dzmitry

    2008-01-01

    Exact equivalent straight waveguide representation is given for a waveguide of arbitrary curvature and torsion. No assumptions regarding refractive index contrast, isotropy of materials, or particular morphology in the waveguide cross section are made. This enables rigorous full-vector modeling o...... of in-plane curved or helically wound waveguides with use of available simulators for straight waveguides without the restrictions of the known approximate equivalent-index formulas....

  18. Quantum waveguides with corners

    Directory of Open Access Journals (Sweden)

    Raymond Nicolas

    2012-04-01

    Full Text Available The simplest modeling of planar quantum waveguides is the Dirichlet eigenproblem for the Laplace operator in unbounded open sets which are uniformly thin in one direction. Here we consider V-shaped guides. Their spectral properties depend essentially on a sole parameter, the opening of the V. The free energy band is a semi-infinite interval bounded from below. As soon as the V is not flat, there are bound states below the free energy band. There are a finite number of them, depending on the opening. This number tends to infinity as the opening tends to 0 (sharply bent V. In this situation, the eigenfunctions concentrate and become self-similar. In contrast, when the opening gets large (almost flat V, the eigenfunctions spread and enjoy a different self-similar structure. We explain all these facts and illustrate them by numerical simulations. La modélisation la plus simple des guides d’ondes quantiques plans est le problème aux valeurs propres pour le laplacien dans des ouverts non bornés qui sont fins dans une direction. Ici nous considérons des guides en forme de V. Leurs propriétés spectrales dépendent essentiellement d’un seul paramètre, l’ouverture du V. La bande d’énergie libre est un intervalle semi-infini borné inférieurement. Dès que le V n’est pas plat, il existe des états liés sous la bande d’énergie libre. Ils sont en nombre fini, fonction de l’ouverture. Ce nombre tend vers l’infini quand l’ouverture tend vers 0 (V très refermé. Dans cette situation, les fonctions propres se concentrent et deviennent auto-similaires. À l’opposé, quand l’ouverture est grande (V très aplati, les fonctions propres s’étalent et jouissent d’une autre structure auto-similaire. Nous expliquons tous ces résultats et les illustrons par des expériences numériques.

  19. Solid-supported biomimetic membranes based on amphiphilic block copolymers

    OpenAIRE

    Kowal, Justyna

    2015-01-01

    Planar artificial membranes based on amphiphilic block copolymers are of high interest due to their potential applications in catalysis, drug screening, sensing, etc. Such polymeric membranes can successfully mimic biological membranes, providing high robustness and stability, which makes them good candidates to be developed in direction of applications. Even though solid-supported polymer membranes have been already investigated to a certain extent, it is still an emerging area. This thesis ...

  20. Characterization of Si3N4/SiO2 optical channel waveguides by photon scanning tunneling microscopy

    Science.gov (United States)

    Wang, Yan; Chudgar, Mona H.; Jackson, Howard E.; Miller, Jeffrey S.; De Brabander, Gregory N.; Boyd, Joseph T.

    1993-01-01

    Photon scanning tunneling microscopy (PSTM) is used to characterize Si3N4/Si02 optical channel waveguides being used for integrated optical-micromechanical sensors. PSTM utilizes an optical fiber tapered to a fine point which is piezoelectrically positioned to measure the decay of the evanescent field intensity associated with the waveguide propagating mode. Evanescent field decays are recorded for both ridge channel waveguides and planar waveguide regions. Values for the local effective refractive index are calculated from the data for both polarizations and compared to model calculations.

  1. An analytical solution for light field modes in waveguides with nonideal cladding

    CERN Document Server

    Arslanov, N M; Moiseev, S A

    2015-01-01

    We have obtained an analytical solution for the dispersion relation of the light field modes in the nanowaveguide structure. The solution has been analyzed for the planar waveguide with metamaterial claddings and dielectric core. The analytical solution is valid within the broadband spectral range and is confirmed by existing numerical calculations. The developed theoretical approach opens vast possibilities for the analytical investigations of the light fields in the various waveguides.

  2. On-chip mid-infrared gas detection using chalcogenide glass waveguide

    Science.gov (United States)

    Han, Z.; Lin, P.; Singh, V.; Kimerling, L.; Hu, J.; Richardson, K.; Agarwal, A.; Tan, D. T. H.

    2016-04-01

    We demonstrate an on-chip sensor for room-temperature detection of methane gas using a broadband spiral chalcogenide glass waveguide coupled with off-chip laser and detector. The waveguide is fabricated using UV lithography patterning and lift-off after thermal evaporation. We measure the intensity change due to the presence and concentration of methane gas in the mid-infrared (MIR) range. This work provides an approach for broadband planar MIR gas sensing.

  3. A Compact, Pi-Mode Extraction Scheme for the Axial B-Field Recirculating Planar Magnetron

    Science.gov (United States)

    2012-07-23

    Figure 4). Thus, in a planar magnetron, the minimum phase velocity, vph , to stay above cutoff in the rectangular waveguide is ℎ = ...as magnetrons, electrons must be accelerated such that they are in synchronism with the phase velocity, vph , of the electromagnetic wave for an...is also likely to be a factor in the waveguide power-loading profile data displayed in Figure 10 (a). It is expected that a careful optimization of

  4. FLUORINATED PHTHALAZINONE-CONTAINING COPOLYIMIDES FOR PASSIVE OPTICAL WAVEGUIDES

    Institute of Scientific and Technical Information of China (English)

    Jin-yan Wang; Gong-xiong Liao; Yuan Song; Shu-de Xiao; Xi-gao Jian

    2005-01-01

    A series of fluorinated copolyimides containing phthalazinone moieties were prepared from 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA), 3,3'4,4'-benzophenone-tetracarboxylic dianhydride (BPDA) and2-(4-aminophenyl)-4-[4-(4-aminophenoxyl)phenyl]-2,3-phthalazin-1-one (DHPZ-2NH2) for making polymeric optical waveguides. The resulting copolymers containing 0-50 mol% BPDA/DHPZ-2NH2 show good solubility and are soluble in some organic polar aprotic solvents. The copolyimides also present excellent thermal stability. These polymers possess high glass transition temperature higher than 603 K and high decomposition temperature above 742 K determined by differential scanning calorimetry and thermogravimetric analysis, respectively, under a nitrogen atmosphere. Their refractive indices could be controlled by varying the ratio of 6FDA and BPDA in the copolymer from 0.5 to 1.0, and the in-plane refractive indices (nTE) range from 1.6366 to 1.6668 and the out-of-plane refractive indices (nTM) from 1.6024 to 1.6280 at 632.8 nm.The polymers birefringence (0.0342-0.0388) is almost independent of the 6FDA content of copolymer, which indicated that the phthalazinone-containing copolyimides could be suitable to fabricate optical waveguides possessing a low polarization dependent loss (PDL).

  5. Optical Filters Utilizing Ion Implanted Bragg Gratings in SOI Waveguides

    Directory of Open Access Journals (Sweden)

    M. P. Bulk

    2008-01-01

    Full Text Available The refractive index modulation associated with the implantation of oxygen or silicon into waveguides formed in silicon-on-insulator (SOI has been investigated to determine the feasibility of producing planar, implantation induced Bragg grating optical filters. A two-dimensional coupled mode theory-based simulation suggests that relatively short grating lengths, on the order of a thousand microns, can exhibit sufficient wavelength suppression, of >10 dB, using the implantation technique. Fabricated planar implanted slab-guided SOI waveguides demonstrated an extinction of −10 dB for TE modes and −6 dB for TM modes for the case of oxygen implantation. Extinctions of −5 dB and −2 dB have been demonstrated with silicon implantation.

  6. Ultrawide Bandwidth 180°-Hybrid-Coupler in Planar Technology

    Directory of Open Access Journals (Sweden)

    Steffen Scherr

    2014-01-01

    Full Text Available A new concept of an ultrawide bandwidth 180°-hybrid-coupler is presented. The ultrawideband design approach is based on the excitation of a coplanar waveguide (CPW mode and a coupled slot line (CSL mode in the same double slotted planar waveguide. The coupler is suitable for realization in planar printed circuit board technology. For verification of the new concept a prototype was designed for the frequency range from 3 GHz to 11 GHz, built, and measured. The measurement results presented in this paper show a good agreement between simulation and measurement and demonstrate the very broadband performance of the new device. The demonstrated coupler with a size of 40 mm × 55 mm exhibits a fractional bandwidth of 114% centered at 7 GHz with a maximum amplitude imbalance of 0.8 dB and a maximum phase imbalance of 5°.

  7. A Cryogenic Waveguide Mount for Microstrip Circuit and Material Characterization

    Science.gov (United States)

    U-yen, Kongpop; Brown, Ari D.; Moseley, Samuel H.; Noroozian, Omid; Wollack, Edward J.

    2016-01-01

    A waveguide split-block fixture used in the characterization of thin-film superconducting planar circuitry at millimeter wavelengths is described in detail. The test fixture is realized from a pair of mode converters, which transition from rectangular-waveguide to on-chip microstrip-line signal propagation via a stepped ridge-guide impedance transformer. The observed performance of the W-band package at 4.2K has a maximum in-band transmission ripple of 2dB between 1.53 and 1.89 times the waveguide cutoff frequency. This metrology approach enables the characterization of superconducting microstrip test structures as a function temperature and frequency. The limitations of the method are discussed and representative data for superconducting Nb and NbTiN thin film microstrip resonators on single-crystal Si dielectric substrates are presented.

  8. Photowritten gratings in ion-exchanged glass waveguides.

    Science.gov (United States)

    Roman, J E; Winick, K A

    1993-05-15

    The fabrication of an ion-exchanged waveguide beam deflector containing a photowritten grating is described. The planar waveguide was fabricated by thermal K(+) exchange in a borosilicate glass. The grating was written by photobleaching an absorption defect centered at 330 am, which was created by gamma-ray irradiation of the glass. The bleaching was accomplished with the 351-nm line from an argon laser. The device achieved 35% deflection efficiency at 633 nm, which corresponded to a grating with a photoinduced index change of 2.6 x 10(-5). This is to our knowledge the first demonstration of an ion-exchanged glass waveguide device containing a permanent photowritten grating.

  9. Design, Fabrication and Properties of Rib Poly(methylmethacrylimide Optical Waveguides

    Directory of Open Access Journals (Sweden)

    P. Nekvindova

    2011-06-01

    Full Text Available We report about design, fabrication and properties of the polymer optical waveguides deposited on silica-on-silicon substrate. The design of the waveguides is based on a concept that geometric dimensions of the single mode polymer waveguide are determined by geometrical parameters of the silica layer. The design of the waveguides was schemed for 650 nm, 850 nm, 1310 nm and 1550 nm wavelength. The design of the presented planar waveguides was realized on the bases of modified dispersion equation while the ridge waveguides design was proposed following the Fischbeck concept. Both designs were refined applying RSoft software using beam propagation method. Proposed shapes of the waveguides were etched by standard photolithography process into the silica layers and polymer waveguide layers were subsequently deposited into the treated substrate by spin coating. Poly(methylmethacrylimide was used as the waveguide core material and polymethylmethacrylate was used as a cover protection layer. Propagation optical loss measurements were done by using the cut-back method and the best samples had optical losses lower than 0.6 dB/cm at 650 nm, 1310 nm and 1550 nm.

  10. Theoretical study of a waveguide THz free electron laser and comparisons with simulations

    Science.gov (United States)

    Shobuda, Yoshihiro; Chin, Yong Ho

    2016-09-01

    In a so-called waveguide free electron laser (FEL) for THz radiations, an extremely small aperture (˜mm ) waveguide is used to confine angularly wide spread radiation fields from a low energy electron beam into a small area. This confinement increases the interaction between the electron beam and the radiation fields to achieve a much higher FEL gain. The radiation fields propagate inside the waveguide as waveguide modes, not like a light flux in a free space FEL. This characteristic behavior of the radiation fields makes intuitive understanding of the waveguide FEL difficult. We developed a three-dimensional waveguide FEL theory to calculate a gain of THz waveguide FEL including the effects of the energy spread, the beam size and the betatron oscillations of an electron beam, and effects of a rectangular waveguide. The FEL gain can be calculated as a function of frequency by solving the dispersion relation. Theoretical gains are compared with simulation results for a waveguide FEL with a planar undulator similar to the KAERI one. Good agreements are obtained.

  11. Theoretical study of a waveguide THz free electron laser and comparisons with simulations

    Directory of Open Access Journals (Sweden)

    Yoshihiro Shobuda

    2016-09-01

    Full Text Available In a so-called waveguide free electron laser (FEL for THz radiations, an extremely small aperture (∼mm waveguide is used to confine angularly wide spread radiation fields from a low energy electron beam into a small area. This confinement increases the interaction between the electron beam and the radiation fields to achieve a much higher FEL gain. The radiation fields propagate inside the waveguide as waveguide modes, not like a light flux in a free space FEL. This characteristic behavior of the radiation fields makes intuitive understanding of the waveguide FEL difficult. We developed a three-dimensional waveguide FEL theory to calculate a gain of THz waveguide FEL including the effects of the energy spread, the beam size and the betatron oscillations of an electron beam, and effects of a rectangular waveguide. The FEL gain can be calculated as a function of frequency by solving the dispersion relation. Theoretical gains are compared with simulation results for a waveguide FEL with a planar undulator similar to the KAERI one. Good agreements are obtained.

  12. Dispersion properties of a nanophotonic Bragg waveguide with finite aperiodic cladding

    CERN Document Server

    Fesenko, Volodymyr I; Shulika, Oleksiy V; Sukhoivanov, Igor A

    2015-01-01

    A comprehensive analysis of guided modes of a novel type of a planar Bragg reflection waveguide which consists of a low refractive index guiding layer sandwiched between two finite aperiodic mirrors is presented. The layers in the mirrors are aperiodically arranged according to the Kolakoski substitution rule. In such a waveguide light is confined inside the core by Bragg reflection from the mirrors, while dispersion characteristics of guided modes strongly depend on aperiodicity of the cladding. Using the transfer matrix formalism bandgap conditions, dispersion characteristics and mode profiles of the guided modes of such Bragg reflection waveguide are studied.

  13. Breathable waveguides for combined light and CO2 delivery to microalgae.

    Science.gov (United States)

    Pierobon, Scott C; Riordon, Jason; Nguyen, Brian; Sinton, David

    2016-06-01

    Suboptimal light and chemical distribution (CO2, O2) in photobioreactors hinder phototrophic microalgal productivity and prevent economically scalable production of biofuels and bioproducts. Current strategies that improve illumination in reactors negatively impact chemical distribution, and vice versa. In this work, an integrated illumination and aeration approach is demonstrated using a gas-permeable planar waveguide that enables combined light and chemical distribution. An optically transparent cellulose acetate butyrate (CAB) slab is used to supply both light and CO2 at various source concentrations to cyanobacteria. The breathable waveguide architecture is capable of cultivating microalgae with over double the growth as achieved with impermeable waveguides. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Design of the low-loss waveguide coil for interferometric integrated optic gyroscopes

    Science.gov (United States)

    Fei, Yao; Yang, Tianshu; Li, Zhaofeng; Liu, Wen; Wang, Xiaodong; Zheng, Wanhua; Yang, Fuhua

    2017-04-01

    With the development of manufacturing technology, the propagation loss of the planar waveguide is getting lower and lower, and the shot-noise-limited sensitivity of an IIOG will be greatly improved. When the propagation loss is getting lower, improper coupling-out waveguide in the waveguide coil may lead to non-ignorable bending loss and crosstalk because of the small radius of curvature and X-junction. In this paper, different coupling-out waveguides have been designed. After calculation and optimization by the beam propagation method, we found the proper coupling-out waveguide having relatively low propagation loss, which can improve the sensitivity of the IIOG. Project supported by the National Natural Science Foundation of China (Nos. 61274066, 61504138, 61474115) and the National Key Research and Development Program of China (No. 2016YFA02005003).

  15. Multiple temperature sensors embedded in an ultrasonic “spiral-like” waveguide

    Directory of Open Access Journals (Sweden)

    Suresh Periyannan

    2017-03-01

    Full Text Available This paper studies the propagation of ultrasound in spiral waveguides, towards distributed temperature measurements on a plane. Finite Element (FE approach was used for understanding the velocity behaviour and consequently designing the spiral waveguide. Temperature measurements were experimentally carried out on planar surface inside a hot chamber. Transduction was performed using a piezo-electric crystal that is attached to one end of the waveguide. Lower order axisymmetric guided ultrasonic modes L(0,1 and T(0,1 were employed. Notches were introduced along the waveguide to obtain ultrasonic wave reflections. Time of fight (TOF differences between the pre-defined reflectors (notches located on the waveguides were used to infer local temperatures. The ultrasonic temperature measurements were compared with commercially available thermocouples.

  16. Resonant-state expansion of light propagation in non-uniform waveguides

    CERN Document Server

    Lobanov, S V; Langbein, W; Muljarov, E A

    2016-01-01

    A new rigorous approach for precise and efficient calculation of light propagation along non-uniform waveguides is presented. Resonant states of a uniform waveguide, which satisfy outgoing-wave boundary conditions, form a natural basis for expansion of the local electromagnetic field. Using such an expansion at fixed frequency, we convert the light propagation along a non-uniform waveguide into an ordinary second-order matrix differential equation for the expansion coefficients along the waveguide. We illustrate the method on examples of planar waveguides with rectangular holes and evaluate its efficiency compared to the aperiodic Fourier modal method and the finite element method, showing improvements of one to two orders of magnitude. A similar improvement can be expected also for applications in other fields of physics showing wave phenomena, such as acoustics and quantum mechanics.

  17. Omnidirectional optical waveguide

    Science.gov (United States)

    Bora, Mihail; Bond, Tiziana C.

    2016-08-02

    In one embodiment, a system includes a scintillator material; a detector coupled to the scintillator material; and an omnidirectional waveguide coupled to the scintillator material, the omnidirectional waveguide comprising: a plurality of first layers comprising one or more materials having a refractive index in a first range; and a plurality of second layers comprising one or more materials having a refractive index in a second range, the second range being lower than the first range, a plurality of interfaces being defined between alternating ones of the first and second layers. In another embodiment, a method includes depositing alternating layers of a material having a relatively high refractive index and a material having a relatively low refractive index on a substrate to form an omnidirectional waveguide; and coupling the omnidirectional waveguide to at least one surface of a scintillator material.

  18. Extreme skin depth waveguides

    CERN Document Server

    Jahani, Saman

    2014-01-01

    Recently, we introduced a paradigm shift in light confinement strategy and introduced a class of extreme skin depth (e-skid) photonic structures (S. Jahani and Z. Jacob, "Transparent sub-diffraction optics: nanoscale light confinement without metal," Optica 1, 96-100 (2014)). Here, we analytically establish that figures of merit related to light confinement in dielectric waveguides are fundamentally tied to the skin depth of waves in the cladding. We contrast the propagation characteristics of the fundamental mode of e-skid waveguides and conventional waveguides to show that the decay constant in the cladding is dramatically larger in e-skid waveguides, which is the origin of sub-diffraction confinement. Finally, we propose an approach to verify the reduced skin depth in experiment using the decrease in the Goos-H\\"anchen phase shift.

  19. Nanoscale waveguiding methods.

    Science.gov (United States)

    Wang, Chia-Jean; Lin, Lih Y

    2007-05-01

    While 32 nm lithography technology is on the horizon for integrated circuit (IC) fabrication, matching the pace for miniaturization with optics has been hampered by the diffraction limit. However, development of nanoscale components and guiding methods is burgeoning through advances in fabrication techniques and materials processing. As waveguiding presents the fundamental issue and cornerstone for ultra-high density photonic ICs, we examine the current state of methods in the field. Namely, plasmonic, metal slot and negative dielectric based waveguides as well as a few sub-micrometer techniques such as nanoribbons, high-index contrast and photonic crystals waveguides are investigated in terms of construction, transmission, and limitations. Furthermore, we discuss in detail quantum dot (QD) arrays as a gain-enabled and flexible means to transmit energy through straight paths and sharp bends. Modeling, fabrication and test results are provided and show that the QD waveguide may be effective as an alternate means to transfer light on sub-diffraction dimensions.

  20. Modes and exceptional points in waveguides with impedance boundary conditions

    CERN Document Server

    Midya, Bikashkali

    2016-01-01

    A planar waveguide with impedance boundary, composed of non-perfect metallic plates, and with passive or active dielectric filling is considered. We show the possibility of selective mode guiding and amplification when homogeneous pump is added to the dielectric, and analyze differences in TE and TM mode propagation. Such a non-conservative system is also shown to feature exceptional points, for specific and experimentally tunable parameters, which are described for a particular case of transparent dielectric.

  1. Advancements in X-ray waveguides and their applications in coherent diffraction imaging

    Energy Technology Data Exchange (ETDEWEB)

    Pelliccia, D. [Institut fuer Synchrotronstrahlung-ANKA Forschungszentrum Karlsruhe Herman-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany)], E-mail: daniele.pelliccia@iss.fzk.de; Bukreeva, I. [Istituto di Fotonica e Nanotecnologie-CNR, Via Cineto Romano 42, 00156 Roma (Italy); Giannini, C.; De Caro, L. [Istituto di Cristallografia-CNR, Via Amendola 122/O, 70126 Bari (Italy); Cedola, A.; Scarinci, F.; Lagomarsino, S. [Istituto di Fotonica e Nanotecnologie-CNR, Via Cineto Romano 42, 00156 Roma (Italy)

    2009-10-15

    X-ray planar waveguides are currently used tools, in synchrotron radiation facilities, to produce a coherent beam with typical dimensions in the range of tens or hundreds of nanometers. The properties of waveguided beams such as divergence and coherence turns out to be very interesting for several applications both in synchrotron and in laboratory sources. These features will be reviewed in the present paper for different coupling methods of the radiation field with the waveguide channel. Details of fabrication procedures and experimental results concerning front coupling waveguide are reported. The waveguide properties can be estimated from the far-field diffracted beam by a Fourier analysis giving the autocorrelation function of the exit field. Due to the high degree of coherence of the exiting beam, X-ray waveguides can be successfully exploited in coherent diffraction imaging experiments. We review results concerning Fresnel coherent diffraction imaging experiments with hard X-rays, using planar waveguides as optical elements in one and two dimensions.

  2. Gap Surface Plasmon Waveguide Analysis

    DEFF Research Database (Denmark)

    Nielsen, Michael Grøndahl; Bozhevolnyi, Sergey I.

    2014-01-01

    Plasmonic waveguides supporting gap surface plasmons (GSPs) localized in a dielectric spacer between metal films are investigated numerically and the waveguiding properties at telecommunication wavelengths are presented. Especially, we emphasize that the mode confinement can advantageously...

  3. Power Budget Analysis for Waveguide-Enhanced Raman Spectroscopy.

    Science.gov (United States)

    Wang, Zilong; Pearce, Stuart J; Lin, Yung-Chun; Zervas, Michalis N; Bartlett, Philip N; Wilkinson, James S

    2016-08-01

    Waveguide-enhanced Raman spectroscopy (WERS) is emerging as an attractive alternative to plasmonic surface-enhanced Raman spectroscopy approaches as it can provide more reproducible quantitative spectra on a robust chip without the need for nanostructured plasmonic materials. Realizing portable WERS systems with high sensitivity using low-cost laser diodes and compact spectrometers requires a detailed analysis of the power budget from laser to spectrometer chip. In this paper, we describe theoretical optimization of planar waveguides for maximum Raman excitation efficiency, demonstrate WERS for toluene on a silicon process compatible high index contrast tantalum pentoxide waveguide, measure the absolute conversion efficiency from pump power to received power in an individual Raman line, and compare this with a power budget analysis of the complete system including collection with an optical fiber and interfacing to a compact spectrometer. Optimized 110 nm thick Ta2O5 waveguides on silica substrates excited at a wavelength of 637 nm are shown experimentally to yield overall system power conversion efficiency of ∼0.5 × 10(-12) from the pump power in the waveguide to the collected Raman power in the 1002 cm(-1) Raman line of toluene, in comparison with a calculated efficiency of 3.9 × 10(-12) Collection efficiency is dictated by the numerical and physical apertures of the spectral detection system but may be improved by further engineering the spatial and angular Raman scattering distributions.

  4. Experimental Demonstration of Luneburg Waveguides

    Directory of Open Access Journals (Sweden)

    Vera N. Smolyaninova

    2015-04-01

    Full Text Available Transformation optics gives rise to numerous unusual optical devices, such as novel metamaterial lenses and invisibility cloaks. Very recently, Mattheakis et al. (Luneburg lens waveguide networks. J. Opt. 2012, 14, 114006 have suggested theoretical design of an optical waveguide, based on a network of Luneburg lenses, which may be useful in sensing and nonlinear optics applications. Here, we report the first experimental realization of such Luneburg waveguides. We have studied wavelength and polarization dependent performance of the waveguides.

  5. Nanoporous polymer liquid core waveguides

    DEFF Research Database (Denmark)

    Gopalakrishnan, Nimi; Christiansen, Mads Brøkner; Ndoni, Sokol

    2010-01-01

    We demonstrate liquid core waveguides defined by UV to enable selective water infiltration in nanoporous polymers, creating an effective refractive index shift Δn=0.13. The mode confinement and propagation loss in these waveguides are presented.......We demonstrate liquid core waveguides defined by UV to enable selective water infiltration in nanoporous polymers, creating an effective refractive index shift Δn=0.13. The mode confinement and propagation loss in these waveguides are presented....

  6. New Polytetrahydrofuran Graft Copolymers.

    Science.gov (United States)

    1979-03-15

    chioroprene) , chiorobutyl - ~~~~~ rubber , bromobutyl rubber , chlorinated EPDM , chlorinated poly(buta— diene) and chlorinated butadiene styrene copolymer...for initial detailed studies (3 ,4 , 6 , 7 — 9 ) . Many soluble metal salts with cations capable of stabilizing an on].um ion polymerization (SO3CF 3

  7. Block coordination copolymers

    Science.gov (United States)

    Koh, Kyoung Moo; Wong-Foy, Antek G; Matzger, Adam J; Benin, Annabelle I; Willis, Richard R

    2012-11-13

    The present invention provides compositions of crystalline coordination copolymers wherein multiple organic molecules are assembled to produce porous framework materials with layered or core-shell structures. These materials are synthesized by sequential growth techniques such as the seed growth technique. In addition, the invention provides a simple procedure for controlling functionality.

  8. DESIGN OF INTEGRATING WAVEGUIDE BIOSENSOR

    Science.gov (United States)

    The Integrating Waveguide Biosensor allows for rapid and sensitive detection of pathogenic agents, cells and proteins via immunoassay or PCR products. The analytes are captured on the surface of the waveguide and then tagged with fluorescent labels. The waveguides are illuminated by excitation light...

  9. Surface transport and stable trapping of particles and cells by an optical waveguide loop.

    Science.gov (United States)

    Hellesø, Olav Gaute; Løvhaugen, Pål; Subramanian, Ananth Z; Wilkinson, James S; Ahluwalia, Balpreet Singh

    2012-09-21

    Waveguide trapping has emerged as a useful technique for parallel and planar transport of particles and biological cells and can be integrated with lab-on-a-chip applications. However, particles trapped on waveguides are continuously propelled forward along the surface of the waveguide. This limits the practical usability of the waveguide trapping technique with other functions (e.g. analysis, imaging) that require particles to be stationary during diagnosis. In this paper, an optical waveguide loop with an intentional gap at the centre is proposed to hold propelled particles and cells. The waveguide acts as a conveyor belt to transport and deliver the particles/cells towards the gap. At the gap, the diverging light fields hold the particles at a fixed position. The proposed waveguide design is numerically studied and experimentally implemented. The optical forces on the particle at the gap are calculated using the finite element method. Experimentally, the method is used to transport and trap micro-particles and red blood cells at the gap with varying separations. The waveguides are only 180 nm thick and thus could be integrated with other functions on the chip, e.g. microfluidics or optical detection, to make an on-chip system for single cell analysis and to study the interaction between cells.

  10. Active Photonic Crystal Waveguides

    DEFF Research Database (Denmark)

    Ek, Sara

    This thesis deals with the fabrication and characterization of active photonic crystal waveguides, realized in III-V semiconductor material with embedded active layers. The platform offering active photonic crystal waveguides has many potential applications. One of these is a compact photonic...... crystal semiconductor optical amplier. As a step towards such a component, photonic crystal waveguides with a single quantum well, 10 quantum wells and three layers of quantum dots are fabricated and characterized. An experimental study of the amplied spontaneous emission and a implied transmission...... are presented in this thesis. A variation of photonic crystal design parameters are used leading to a spectral shift of the dispersion, it is veried that the observed effects shift accordingly. An enhancement of the amplified spontaneous emission was observed close to the band edge, where light is slowed down...

  11. Single-mode glass waveguide technology for optical interchip communication on board level

    Science.gov (United States)

    Brusberg, Lars; Neitz, Marcel; Schröder, Henning

    2012-01-01

    The large bandwidth demand in long-distance telecom networks lead to single-mode fiber interconnects as result of low dispersion, low loss and dense wavelength multiplexing possibilities. In contrast, multi-mode interconnects are suitable for much shorter lengths up to 300 meters and are promising for optical links between racks and on board level. Active optical cables based on multi-mode fiber links are at the market and research in multi-mode waveguide integration on board level is still going on. Compared to multi-mode, a single-mode waveguide has much more integration potential because of core diameters of around 20% of a multi-mode waveguide by a much larger bandwidth. But light coupling in single-mode waveguides is much more challenging because of lower coupling tolerances. Together with the silicon photonics technology, a single-mode waveguide technology on board-level will be the straight forward development goal for chip-to-chip optical interconnects integration. Such a hybrid packaging platform providing 3D optical single-mode links bridges the gap between novel photonic integrated circuits and the glass fiber based long-distance telecom networks. Following we introduce our 3D photonic packaging approach based on thin glass substrates with planar integrated optical single-mode waveguides for fiber-to-chip and chip-to-chip interconnects. This novel packaging approach merges micro-system packaging and glass integrated optics. It consists of a thin glass substrate with planar integrated singlemode waveguide circuits, optical mirrors and lenses providing an integration platform for photonic IC assembly and optical fiber interconnect. Thin glass is commercially available in panel and wafer formats and characterizes excellent optical and high-frequency properties. That makes it perfect for microsystem packaging. The paper presents recent results in single-mode waveguide technology on wafer level and waveguide characterization. Furthermore the integration in a

  12. Analytical and numerical study on grating depth effects in grating coupled waveguide sensors

    DEFF Research Database (Denmark)

    Horvath, R.; Wilcox, L.C.; Pedersen, H.C.;

    2005-01-01

    The in-coupling process for grating-coupled planar optical waveguide sensors is investigated in the case of TE waves. A simple analytical model based on the Rayleigh-Fourier-Kiselev method is applied to take into account the depth of the grating coupler, which is usually neglected in the modeling...

  13. Optical waveguiding and temperature dependent photoluminescence of nanotubulars grown from molecular building blocks

    DEFF Research Database (Denmark)

    Maibohm, Christian; Rastedt, Maren; Kutscher, Frauke

    2013-01-01

    Optical waveguiding of blue light after UV-excitation is demonstrated in bundles of organic nanotubulars obtained via template assisted aggregation of the small p-conjugated non planar molecules 17H-Tetrabenzo[ a,c,g,i]fluorene (17H-Tbf) and 17-Trimethylsilyltetrabenzo[a,c,g,i]fluorene (TMS-Tbf)....

  14. Frontiers in Planar Lightwave Circuit Technology Design, Simulation, and Fabrication

    CERN Document Server

    Janz, Siegfried; Tanev, Stoyan

    2005-01-01

    This book is the result of the NATO Advanced Research Workshop on Frontiers in Planar Lightwave Circuit Technology, which took place in Ottawa, Canada from September 21-25, 2004. Many of the world’s leading experts in integrated photonic design, theory and experiment were invited to give lectures in their fields of expertise, and participate in discussions on current research and applications, as well as the new directions planar lightwave circuit technology is evolving towards. The sum of their contributions to this book constitutes an excellent record of many key issues and scientific problems in planar lightwave circuit research at the time of writing. In this volume the reader will find detailed overviews of experimental and theoretical work in high index contrast waveguide systems, micro-optical resonators, nonlinear optics, and advanced optical simulation methods, as well as articles describing emerging applications of integrated optics for medical and biological applications.

  15. Waveguide apparatuses and methods

    Science.gov (United States)

    Spencer, James E.

    2016-05-10

    Optical fiber waveguides and related approaches are implemented to facilitate communication. As may be implemented in accordance with one or more embodiments, a waveguide has a substrate including a lattice structure having a plurality of lattice regions with a dielectric constant that is different than that of the substrate, a defect in the lattice, and one or more deviations from the lattice. The defect acts with trapped transverse modes (e.g., magnetic and/or electric modes) and facilitates wave propagation along a longitudinal direction while confining the wave transversely. The deviation(s) from the lattice produces additional modes and/or coupling effects.

  16. Waveguides for walking droplets

    CERN Document Server

    Filoux, Boris; Schlagheck, Peter; Vandewalle, Nicolas

    2015-01-01

    When gently placing a droplet onto a vertically vibrated bath, a drop can bounce permanently. Upon increasing the forcing acceleration, the droplet is propelled by the wave it generates and becomes a walker with a well defined speed. We investigate the confinement of a walker in different rectangular cavities, used as waveguides for the Faraday waves emitted by successive droplet bounces. By studying the walker velocities, we discover that 1d confinement is optimal for narrow channels. We also propose an analogy with waveguide models based on the observation of the Faraday instability within the channels.

  17. Actively coupled optical waveguides

    Science.gov (United States)

    Alexeeva, N. V.; Barashenkov, I. V.; Rayanov, K.; Flach, S.

    2014-01-01

    We consider light propagation through a pair of nonlinear optical waveguides with absorption, placed in a medium with power gain. The active medium boosts the in-phase component of the overlapping evanescent fields of the guides, while the nonlinearity of the guides couples it to the damped out-of-phase component creating a feedback loop. As a result, the structure exhibits stable stationary and oscillatory regimes in a wide range of gain-loss ratios. We show that the pair of actively coupled (AC) waveguides can act as a stationary or integrate-and-fire comparator sensitive to tiny differences in their input powers.

  18. Metamaterial Loadings for Waveguide Miniaturization

    CERN Document Server

    Odabasi, H

    2013-01-01

    We show that a rectangular metallic waveguide loaded with metamaterial elements consisting of electric-field coupled (ELC) resonators placed at the side walls can operate well below the cutoff frequency of the respective unloaded waveguide. The dispersion diagrams indicate that propagating modes in ELC-loaded waveguides are of forward-type for both TE and TM modes. We also study the dispersion diagram and transmission characteristics of rectangular metallic waveguides simultaneously loaded with ELCs and split ring resonators (SRRs). Such doubly-loaded waveguides can support both forward wave and backward waves, and provide independent control of the propagation characteristics for the respective modes.

  19. Monolithic photonic integration of suspended light emitting diode, waveguide and photodetector

    CERN Document Server

    Wang, Yongjin; Gao, Xumin; Cai, Wei; Xu, Yin; Yuan, Jialei; Zhu, Guixia; Yang, Yongchao; Cao, Xun; Zhu, Hongbo; Gruenberg, Peter

    2015-01-01

    We report here a monolithic photonic integration of light emitting diode (LED) with waveguide and photodetector to build a highly-integrated photonic system to perform functionalities on the GaN-on-silicon platform. Suspended p-n junction InGaN/GaN multiple quantum wells (MQWs) are used for device fabrication. Part of the LED emission is coupled into suspended waveguide and then, the guided light laterally propagates along the waveguide and is finally sensed by the photodetector. Planar optical communication experimentally demonstrates that the proof-of-concept monolithic photonic integration system can achieve the on-chip optical interconnects. This work paves the way towards novel active electro-optical sensing system and planar optical communication in the visible range.

  20. Absorption enhancement and total absorption in a graphene-waveguide hybrid structure

    Science.gov (United States)

    Guo, Jun; Wu, Leiming; Dai, Xiaoyu; Xiang, Yuanjiang; Fan, Dianyuan

    2017-02-01

    We propose a graphene/planar waveguide hybrid structure, and demonstrate total absorption in the visible wavelength range by means of attenuated total reflectance. The excitation of planar waveguide mode, which has strong near field enhancement and increased light interaction length with graphene, plays a vital role in total absorption. We analyze the origin and physical insight of total absorption theoretically by using an approximated reflectance, and show how to design such hybrid structure numerically. Utilizing the tunability of doped graphene, we discuss the possible application in optical modulators. We also achieve broadband absorption enhancement in near-IR range by cascading multiple graphene-waveguide hybrid structures. We believe our results will be useful not only for potential applications in optical devices, but also for studying other two-dimension materials.

  1. Absorption enhancement and total absorption in a graphene-waveguide hybrid structure

    Directory of Open Access Journals (Sweden)

    Jun Guo

    2017-02-01

    Full Text Available We propose a graphene/planar waveguide hybrid structure, and demonstrate total absorption in the visible wavelength range by means of attenuated total reflectance. The excitation of planar waveguide mode, which has strong near field enhancement and increased light interaction length with graphene, plays a vital role in total absorption. We analyze the origin and physical insight of total absorption theoretically by using an approximated reflectance, and show how to design such hybrid structure numerically. Utilizing the tunability of doped graphene, we discuss the possible application in optical modulators. We also achieve broadband absorption enhancement in near-IR range by cascading multiple graphene-waveguide hybrid structures. We believe our results will be useful not only for potential applications in optical devices, but also for studying other two-dimension materials.

  2. Silica-based planar lightwave circuits; Sekieikei planar koha kairogata shusekiko buhin

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, S. [NTT Opto-Electronics Laboratories, Tokyo (Japan)

    1997-08-01

    This paper describes the latest trend of silica-based planar lightwave circuit (PLC) technology. For the waveguide composing PLC, silica-based waveguides using various dopants based on SiO2 have been positively developed. Silica-based glass is physically and chemically stable, and has a good matching with optical fiber transmitter. The optical branch circuit which branches and meets light is a basically significant part for constructing networks. There are splitter with multiple connected Y-branches, wavelength independent coupler using a Mach-Zender interferometer, and NtimesN star coupler. The optical switch is a basic circuit for switching the optical path of light signal. Arrayed-waveguide grating type branching and meeting circuits are also described. The programmable PLC attracts attention as an advanced PLC for realizing various optical filtration performances. To extend further functions of PLC, hybrid integration of optical function device, such as semiconductor laser, and electrical wiring on the PLC platform is investigated. 12 refs., 7 figs., 2 tabs.

  3. Diluted melt proton exchange slab waveguides in LiNbO3: A new fabrication and characterization method

    DEFF Research Database (Denmark)

    Veng, Torben; Skettrup, Torben

    1997-01-01

    A method of dilute-melt proton exchange employing a mixture of glycerol and KHSO4 with lithium benzoate added is used to fabricate planar waveguides in c-cut LiNbO3. With this exchange melt system the waveguide refractive index profiles can be fabricated with a high degree of reproducibility. In ...... refractive index change and composition of this glycerol, KHSO4 and lithium benzoate exchange melt system....

  4. Planar Difference Functions

    CERN Document Server

    Hall, Joanne L; Donovan, Diane

    2012-01-01

    In 1980 Alltop produced a family of cubic phase sequences that nearly meet the Welch bound for maximum non-peak correlation magnitude. This family of sequences were shown by Wooters and Fields to be useful for quantum state tomography. Alltop's construction used a function that is not planar, but whose difference function is planar. In this paper we show that Alltop type functions cannot exist in fields of characteristic 3 and that for a known class of planar functions, $x^3$ is the only Alltop type function.

  5. Gratings in polymeric waveguides

    Science.gov (United States)

    Mishakov, G.; Sokolov, V.; Kocabas, A.; Aydinli, A.

    2007-04-01

    Laser-induced formation of polymer Bragg grating filters for Dense Wavelength Division Multiplexing (DWDM) applications is discussed. Acrylate monomers halogenated with both fluorine and chlorine, which possess absorption losses less than 0.25 dB/cm and wide choice of refractive indices (from 1.3 to 1.5) in the 1.5 μm telecom wavelength region were used. The monomers are highly intermixable thus permitting to adjust the refractive index of the composition within +/-0.0001. Moreover they are photocurable under UV exposure and exhibit high contrast in polymerization. These properties make halogenated acrylates very promising for fabricating polymeric waveguides and photonic circuits. Single-mode polymer waveguides were fabricated on silicon wafers using resistless contact lithography. Submicron index gratings have been written in polymer waveguides using holographic exposure with He-Cd laser beam (325 nm) through a phase mask. Both uniform and apodized gratings have been fabricated. The gratings are stable and are not erased by uniform UV exposure. The waveguide gratings possess narrowband reflection spectra in the 1.5 μm wavelength region of 0.4 nm width, nearly rectangular shape of the stopband and reflectivity R > 99%. The fabricated Bragg grating filters can be used for multiplexing/demultiplexing optical signals in high-speed DWDM optical fiber networks.

  6. Folded waveguide resonator

    DEFF Research Database (Denmark)

    2013-01-01

    A waveguide resonator comprising a number of side walls defining a cavity enclosed by said sidewalls defining the cavity; and two or more conductive plates extending into the cavity, each conductive plate having a first side and a second side opposite the first side, and wherein the conductive...

  7. Information rate of waveguide

    OpenAIRE

    Giovannetti, Vittorio; Lloyd, Seth; Maccone, Lorenzo; Shapiro, Jeffrey H.

    2003-01-01

    We calculate the communication capacity of a broadband electromagnetic waveguide as a function of its spatial dimensions and input power. We analyze the two cases in which either all the available modes or only a single directional mode are employed. The results are compared with those for the free space bosonic channel.

  8. Nanoscale waveguiding methods

    Directory of Open Access Journals (Sweden)

    Wang Chia-Jean

    2007-01-01

    Full Text Available AbstractWhile 32 nm lithography technology is on the horizon for integrated circuit (IC fabrication, matching the pace for miniaturization with optics has been hampered by the diffraction limit. However, development of nanoscale components and guiding methods is burgeoning through advances in fabrication techniques and materials processing. As waveguiding presents the fundamental issue and cornerstone for ultra-high density photonic ICs, we examine the current state of methods in the field. Namely, plasmonic, metal slot and negative dielectric based waveguides as well as a few sub-micrometer techniques such as nanoribbons, high-index contrast and photonic crystals waveguides are investigated in terms of construction, transmission, and limitations. Furthermore, we discuss in detail quantum dot (QD arrays as a gain-enabled and flexible means to transmit energy through straight paths and sharp bends. Modeling, fabrication and test results are provided and show that the QD waveguide may be effective as an alternate means to transfer light on sub-diffraction dimensions.

  9. Optical waveguide sensors

    NARCIS (Netherlands)

    Fluitman, J.; Popma, Th.

    1986-01-01

    An overview of the field of optical waveguide sensors is presented. Some emphasis is laid on the development of a single scheme under which the diversity of sensor principles can be arranged. First three types of sensors are distinguished: intrinsic, extrinsic and active. Next, two steps are disting

  10. STUDY ON PET-PA66 COPOLYMER

    Institute of Scientific and Technical Information of China (English)

    WU Rongrui; SHI Weitong

    1992-01-01

    In this work the PET-PA66 copolymers are obtained. The characterization of chemical structure of copolymer chain by NMR method is also given . It is shown that when the 66 Nylon salt is added in the copolycondensation, the adipic acid and hexamethylenediamine reacted mainly by itself and the obtained copolymer is a random copolymer, and when the Nylon 66 oligomer is added, the obtained copolymer is a block copolymer. The result of NMR analysis is demonstrated by properties investigation.

  11. Block copolymer battery separator

    Energy Technology Data Exchange (ETDEWEB)

    Wong, David; Balsara, Nitash Pervez

    2016-04-26

    The invention herein described is the use of a block copolymer/homopolymer blend for creating nanoporous materials for transport applications. Specifically, this is demonstrated by using the block copolymer poly(styrene-block-ethylene-block-styrene) (SES) and blending it with homopolymer polystyrene (PS). After blending the polymers, a film is cast, and the film is submerged in tetrahydrofuran, which removes the PS. This creates a nanoporous polymer film, whereby the holes are lined with PS. Control of morphology of the system is achieved by manipulating the amount of PS added and the relative size of the PS added. The porous nature of these films was demonstrated by measuring the ionic conductivity in a traditional battery electrolyte, 1M LiPF.sub.6 in EC/DEC (1:1 v/v) using AC impedance spectroscopy and comparing these results to commercially available battery separators.

  12. Block copolymer battery separator

    Science.gov (United States)

    Wong, David; Balsara, Nitash Pervez

    2016-04-26

    The invention herein described is the use of a block copolymer/homopolymer blend for creating nanoporous materials for transport applications. Specifically, this is demonstrated by using the block copolymer poly(styrene-block-ethylene-block-styrene) (SES) and blending it with homopolymer polystyrene (PS). After blending the polymers, a film is cast, and the film is submerged in tetrahydrofuran, which removes the PS. This creates a nanoporous polymer film, whereby the holes are lined with PS. Control of morphology of the system is achieved by manipulating the amount of PS added and the relative size of the PS added. The porous nature of these films was demonstrated by measuring the ionic conductivity in a traditional battery electrolyte, 1M LiPF.sub.6 in EC/DEC (1:1 v/v) using AC impedance spectroscopy and comparing these results to commercially available battery separators.

  13. Magnetic routing of light-induced waveguides

    Science.gov (United States)

    Izdebskaya, Yana; Shvedov, Vladlen; Assanto, Gaetano; Krolikowski, Wieslaw

    2017-01-01

    Among photofunctional materials that can be employed to control the propagation of light by modifying their properties, soft dielectrics such as nematic liquid crystals (NLCs) stand out for their large all-optical response. Through reorientation, the molecular distribution of NLCs can be modified by the electric field of light, permitting functional operations and supporting self-localized light beams or spatial optical solitons. To date, the generation and routing of such solitons have been limited by the boundary conditions employed to tailor the properties of NLCs in planar cells or capillaries. Here we report on spatial solitons in bulk NLCs with no lateral anchoring, where the application of an external magnetic field effectively controls the direction of propagation and the angular steering of the self-trapped wavepackets. Our results entail a completely new approach to the routing of self-localized beams and light-induced waveguides in three dimensions, without the usual limitations imposed by transverse boundary conditions. PMID:28198374

  14. Planar Resonators for Metamaterials

    Directory of Open Access Journals (Sweden)

    M. Blaha

    2012-09-01

    Full Text Available This paper presents the results of an investigation into a combination of electric and magnetic planar resonators in order to design the building element of a volumetric metamaterial showing simultaneously negative electric and magnetic polarizabilities under irradiation by an electromagnetic wave. Two combinations of particular planar resonators are taken into consideration. These planar resonators are an electric dipole, a split ring resonator and a double H-shaped resonator. The response of the single resonant particle composed of a resonator with an electric response and a resonator with a magnetic response is strongly anisotropic. Proper spatial arrangement of these particles can make the response isotropic. This is obtained by proper placement of six planar resonators on the surface of a cube that now represents a metamaterial unit cell. The cells are distributed in space with 3D periodicity.

  15. Vertical coupling of laser glass microspheres to buried silicon nitride ellipses and waveguides

    CERN Document Server

    Navarro-Urrios, Daniel; Capuj, Nestor E; Berencen, Yonder; Garrido, Blas; Tredicucci, Alessandro

    2015-01-01

    We demonstrate the integration of Nd3+ doped Barium-Titanium-Silicate microsphere lasers with a Silicon Nitride photonic platform. Devices with two different geometrical configurations for extracting the laser light to buried waveguides have been fabricated and characterized. The first configuration relies on a standard coupling scheme, where the microspheres are placed over strip waveguides. The second is based on a buried elliptical geometry whose working principle is that of an elliptical mirror. In the latter case, the input of a strip waveguide is placed on one focus of the ellipse, while a lasing microsphere is placed on top of the other focus. The fabricated elliptical geometry (ellipticity=0.9) presents a light collecting capacity that is 50% greater than that of the standard waveguide coupling configuration and could be further improved by increasing the ellipticity. Moreover, since the dimensions of the spheres are much smaller than those of the ellipses, surface planarization is not required. On th...

  16. A Strip-Loading Optical Waveguide Using Well Poled Stability Organic/Inorganic Hybrid Materials

    Institute of Scientific and Technical Information of China (English)

    GAO Wei-Nan; TIAN Mei-Qiang; SUN Xiao-Qiang; WANG Wei; DENG Ling; GAO Lei; ZHANG Da-Ming

    2009-01-01

    An optical waveguide for a polymer modulator based on organic/inorganic hybrid electro-optic (EO) materials is designed and fabricated by utilizing a strip-loading structure.This hybrid material has a controllable refractive index,high EO coefficient and good poled stability,which are suitable for the EO modulators and switches.The embedded waveguide made of the above EO material can reduce the coupling loss. The light is coupled into the gnided-core layer and then undergoes a transition from the buried waveguide into the EO material.Obvious modulation is observed by application of ac voltage to the EO material.The measured Vπ of co-planar waveguide (CPW) is 5 V for the Mach-Zehnder (MZ) modulator in length of 3.5cm.

  17. Ion-exchanged tapered-waveguide laser in neodymium-doped BK7 glass.

    Science.gov (United States)

    Hettrick, S J; Mackenzie, J I; Harris, R D; Wilkinson, J S; Shepherd, D P; Tropper, A C

    2000-10-01

    We report what is to our knowledge the first operation of a planar dielectric tapered-waveguide laser. The waveguide laser is fabricated by potassium-ion exchange in Nd(3+) -doped BK7 glass and consists of a single-mode channel waveguide of a few micrometers' width followed by a linear taper up to a broad region with a width of ~180microm . A slope efficiency of 42% is found both in the tapers and in standard channel waveguides fabricated upon the same substrate, indicating that the tapers and the channels have similar internal losses; hence the low-loss nature of the tapered beam expansion. The output from either end of the tapered structure is found to be nearly diffraction limited.

  18. Low-Loss Silica-Based Optical Film Waveguides Deposited by Helicon-Activated Reactive Evaporation

    Science.gov (United States)

    Bulla, Douglas A. P.; Li, Wei-Tang; Charles, Christine; Boswell, Rod; Ankiewicz, Adrian; Love, John D.

    2005-03-01

    Planar silica-based optical waveguides have been deposited by a plasma helicon-activated reactive evaporation system, at a low temperature and with reduced hydrogen contamination, on thermally oxidized silicon wafers. The transmission loss of the rib waveguides, formed on the deposited films by etching with hydrofluoric acid, is determined to be lower than 0.1 and 0.7 dB/cm at wavelengths of 1310 and 1510 nm, respectively, for TE polarization. The influence of substrate leakage on propagation loss is determined numerically and compared with experimental results for TE and TM polarizations. The presence of the OH vibrational overtone band in the fabricated waveguides, at a wavelength of around 1385 nm, is discussed in terms of the waveguide structure.

  19. Monolithic integration of microfluidic channels and optical waveguides in silica on silicon.

    Science.gov (United States)

    Friis, P; Hoppe, K; Leistiko, O; Mogensen, K B; Hübner, J; Kutter, J P

    2001-12-01

    Sealing of the flow channel is an important aspect during integration of microfluidic channels and optical waveguides. The uneven topography of many waveguide-fabrication techniques will lead to leakage of the fluid channels. Planarization methods such as chemical mechanical polishing or the etch-back technique are possible, but troublesome. We present a simple but efficient alternative: By means of changing the waveguide layout, bonding pads are formed along the microfluidic channels. With the same height as the waveguide, they effectively prevent leakage and hermetically seal the channels during bonding. Negligible influence on light propagation is found when 10-mum-wide bonding pads are used. Fabricated microsystems with application in absorbance measurements and flow cytometry are presented.

  20. Squeezing red blood cells on an optical waveguide to monitor cell deformability during blood storage.

    Science.gov (United States)

    Ahluwalia, Balpreet Singh; McCourt, Peter; Oteiza, Ana; Wilkinson, James S; Huser, Thomas R; Hellesø, Olav Gaute

    2015-01-07

    Red blood cells squeeze through micro-capillaries as part of blood circulation in the body. The deformability of red blood cells is thus critical for blood circulation. In this work, we report a method to optically squeeze red blood cells using the evanescent field present on top of a planar waveguide chip. The optical forces from a narrow waveguide are used to squeeze red blood cells to a size comparable to the waveguide width. Optical forces and pressure distributions on the cells are numerically computed to explain the squeezing process. The proposed technique is used to quantify the loss of blood deformability that occurs during blood storage lesion. Squeezing red blood cells using waveguides is a sensitive technique and works simultaneously on several cells, making the method suitable for monitoring stored blood.

  1. Multichannel waveguides for the simultaneous detection of disease biomarkers

    Energy Technology Data Exchange (ETDEWEB)

    Mukundan, Harshini [Los Alamos National Laboratory; Price, Dominique Z [Los Alamos National Laboratory; Grace, Wynne K [Los Alamos National Laboratory; Swanson, Basil I [Los Alamos National Laboratory

    2009-01-01

    The sensor team at the Los Alamos National Laboratory has developed a waveguide-based optical biosensor that has previously been used for the detection of biomarkers associated with diseases such as tuberculosis, breast cancer, anthrax and influenza in complex biological samples (e.g., serum and urine). However, no single biomarker can accurately predict disease. To address this issue, we developed a multiplex assay for the detection of components of the Bacillus anthracis lethal toxin on single mode planar optical waveguides with tunable quantum dots as the fluorescence reporter. This limited ability to multiplex is still insufficient for accurate detection of disease or for monitoring prognosis. In this manuscript, we demonstrate for the first time, the design, fabrication and successful evaluation of a multichannel planar optical waveguide for the simultaneous detection of at least three unknown samples in quadruplicate. We demonstrate the simultaneous, rapid (30 min), quantitative (with internal standard) and sensitive (limit of detection of 1 pM) detection of protective antigen and lethal factor of Bacillus anthracis in complex biological samples (serum) using specific monoclonal antibodies labeled with quantum dots as the fluorescence reporter.

  2. Learning planar ising models

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Jason K [Los Alamos National Laboratory; Chertkov, Michael [Los Alamos National Laboratory; Netrapalli, Praneeth [STUDENT UT AUSTIN

    2010-11-12

    Inference and learning of graphical models are both well-studied problems in statistics and machine learning that have found many applications in science and engineering. However, exact inference is intractable in general graphical models, which suggests the problem of seeking the best approximation to a collection of random variables within some tractable family of graphical models. In this paper, we focus our attention on the class of planar Ising models, for which inference is tractable using techniques of statistical physics [Kac and Ward; Kasteleyn]. Based on these techniques and recent methods for planarity testing and planar embedding [Chrobak and Payne], we propose a simple greedy algorithm for learning the best planar Ising model to approximate an arbitrary collection of binary random variables (possibly from sample data). Given the set of all pairwise correlations among variables, we select a planar graph and optimal planar Ising model defined on this graph to best approximate that set of correlations. We present the results of numerical experiments evaluating the performance of our algorithm.

  3. Theory of a Traveling Wave Feed for a Planar Slot Array Antenna

    Science.gov (United States)

    Rengarajan, Sembiam

    2012-01-01

    Planar arrays of waveguide-fed slots have been employed in many radar and remote sensing applications. Such arrays are designed in the standing wave configuration because of high efficiency. Traveling wave arrays can produce greater bandwidth at the expense of efficiency due to power loss in the load or loads. Traveling wave planar slot arrays may be designed with a long feed waveguide consisting of centered-inclined coupling slots. The feed waveguide is terminated in a matched load, and the element spacing in the feed waveguide is chosen to produce a beam squinted from the broadside. The traveling wave planar slot array consists of a long feed waveguide containing resonant-centered inclined coupling slots in the broad wall, coupling power into an array of stacked radiating waveguides orthogonal to it. The radiating waveguides consist of longitudinal offset radiating slots in a standing wave configuration. For the traveling wave feed of a planar slot array, one has to design the tilt angle and length of each coupling slot such that the amplitude and phase of excitation of each radiating waveguide are close to the desired values. The coupling slot spacing is chosen for an appropriate beam squint. Scattering matrix parameters of resonant coupling slots are used in the design process to produce appropriate excitations of radiating waveguides with constraints placed only on amplitudes. Since the radiating slots in each radiating waveguide are designed to produce a certain total admittance, the scattering (S) matrix of each coupling slot is reduced to a 2x2 matrix. Elements of each 2x2 S-matrix and the amount of coupling into the corresponding radiating waveguide are expressed in terms of the element S11. S matrices are converted into transmission (T) matrices, and the T matrices are multiplied to cascade the coupling slots and waveguide sections, starting from the load end and proceeding towards the source. While the use of non-resonant coupling slots may provide an

  4. Experimental investigation of plasmofluidic waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Ku, Bonwoo; Kwon, Min-Suk, E-mail: mskwon@unist.ac.kr [School of Electrical and Computer Engineering, UNIST, 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 689-798 (Korea, Republic of); Shin, Jin-Soo [Department of Electrical Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)

    2015-11-16

    Plasmofluidic waveguides are based on guiding light which is strongly confined in fluid with the assistance of a surface plasmon polariton. To realize plasmofluidic waveguides, metal-insulator-silicon-insulator-metal (MISIM) waveguides, which are hybrid plasmonic waveguides fabricated using standard complementary metal-oxide-semiconductor technology, are employed. The insulator of the MISIM waveguide is removed to form 30-nm-wide channels, and they are filled with fluid. The plasmofluidic waveguide has a subwavelength-scale mode area since its mode is strongly confined in the fluid. The waveguides are experimentally characterized for different fluids. When the refractive index of the fluid is 1.440, the plasmofluidic waveguide with 190-nm-wide silicon has propagation loss of 0.46 dB/μm; the coupling loss between it and an ordinary silicon photonic waveguide is 1.79 dB. The propagation and coupling losses may be reduced if a few fabrication-induced imperfections are removed. The plasmofluidic waveguide may pave the way to a dynamically phase-tunable ultracompact device.

  5. Coupling Between Waveguide-Fed Slot Arrays

    Science.gov (United States)

    Rengarajan, Sembiam

    2011-01-01

    Coupling between two waveguide-fed planar slot arrays has been investigated using full-wave analysis. The analysis employs the method-of-moments solution to the pertinent coupled integral equations for the aperture electric field of all slots. In order to compute coupling between two arrays, the input port of the first array is excited with a TE(sub 10) mode wave while the second one is match-terminated. After solving the moment method matrix equations, the aperture fields of all slots are obtained and thereby the TE(sub 10) mode wave received at the input port of the second array is determined. Coupling between two arrays is the ratio of the wave amplitude arriving in the second array port to the incident wave amplitude at the first array port. The coupling mechanism has been studied as a function of spacing between arrays in different directions, e.g. the electric field plane, the magnetic field plane, and the diagonal plane. Computed coupling values are presented for different array geometries. This work is novel since it provides a good understanding of coupling between waveguide-fed slot arrays as a function of spacing and orientation for different aperture distributions and array architectures. This serves as a useful tool for antenna design engineers and system engineers.

  6. Design of an ultra-thin near-eye display with geometrical waveguide and freeform optics.

    Science.gov (United States)

    Cheng, Dewen; Wang, Yongtian; Xu, Chen; Song, Weitao; Jin, Guofan

    2014-08-25

    Small thickness and light weight are two important requirements for a see-through near-eye display which are achieved in this paper by using two advanced technologies: geometrical waveguide and freeform optics. A major problem associated with the geometrical waveguide is the stray light which can severely degrade the display quality. The causes and solutions to this problem are thoroughly studied. A mathematical model of the waveguide is established and a non-sequential ray tracing algorithm is developed, which enable us to carefully examine the stray light of the planar waveguide and explore a global searching method to find an optimum design with the least amount of stray light. A projection optics using freeform surfaces on a wedge shaped prism is also designed. The near-eye display integrating the projection optics and the waveguide has a field of view of 28°, an exit pupil diameter of 9.6mm and an exit pupil distance of 20mm. In our final design, the proportion of the stray light energy over the image output energy of the waveguide is reduced to 2%, the modulation transfer function values across the entire field of the eyepiece are above 0.5 at 30 line pairs/mm (lps/mm). A proof-of-concept prototype of the proposed geometrical waveguide near-eye display is developed and demonstrated.

  7. Phonon waveguides for electromechanical circuits

    Science.gov (United States)

    Hatanaka, D.; Mahboob, I.; Onomitsu, K.; Yamaguchi, H.

    2014-07-01

    Nanoelectromechanical systems (NEMS), utilizing localized mechanical vibrations, have found application in sensors, signal processors and in the study of macroscopic quantum mechanics. The integration of multiple mechanical elements via electrical or optical means remains a challenge in the realization of NEMS circuits. Here, we develop a phonon waveguide using a one-dimensional array of suspended membranes that offers purely mechanical means to integrate isolated NEMS resonators. We demonstrate that the phonon waveguide can support and guide mechanical vibrations and that the periodic membrane arrangement also creates a phonon bandgap that enables control of the phonon propagation velocity. Furthermore, embedding a phonon cavity into the phonon waveguide allows mobile mechanical vibrations to be dynamically switched or transferred from the waveguide to the cavity, thereby illustrating the viability of waveguide-resonator coupling. These highly functional traits of the phonon waveguide architecture exhibit all the components necessary to permit the realization of all-phononic NEMS circuits.

  8. Polyether/Polyester Graft Copolymers

    Science.gov (United States)

    Bell, Vernon L., Jr.; Wakelyn, N.; Stoakley, D. M.; Proctor, K. M.

    1986-01-01

    Higher solvent resistance achieved along with lower melting temperature. New technique provides method of preparing copolymers with polypivalolactone segments grafted onto poly (2,6-dimethyl-phenylene oxide) backbone. Process makes strong materials with improved solvent resistance and crystalline, thermally-reversible crosslinks. Resulting graft copolymers easier to fabricate into useful articles, including thin films, sheets, fibers, foams, laminates, and moldings.

  9. Waveguide submillimeter mixers

    Science.gov (United States)

    Goldsmith, Paul F.; Erickson, Neal R.

    1986-01-01

    A waveguide Schottky barrier diode mixer, which in preliminary tests has yielded a single sideband receiver noise temperature of 4300 K at 692 GHz, when cooled to 77 K is presented. Further refinements and operation at 20 K should produce a significant improvement in performance. From a system point of view, the very high efficiency of the radiation pattern produced by the conical feedhorn with cylindrical corrector mirror enhances the effective sensitivity by a factor of 1.5 to 2 compared to open-structure corner-reflector systems. A second-harmonic mixer for 557 GHz, also in the fundamental mode rectangular waveguide was developed. When combined with a frequency-tripled Gunn oscillator, this makes an extremely compact and lightweight submillimeter radiometer.

  10. Miniaturized dielectric waveguide filters

    Science.gov (United States)

    Sandhu, Muhammad Y.; Hunter, Ian C.

    2016-10-01

    Design techniques for a new class of integrated monolithic high-permittivity ceramic waveguide filters are presented. These filters enable a size reduction of 50% compared to air-filled transverse electromagnetic filters with the same unloaded Q-factor. Designs for Chebyshev and asymmetric generalised Chebyshev filter and a diplexer are presented with experimental results for an 1800 MHz Chebyshev filter and a 1700 MHz generalised Chebyshev filter showing excellent agreement with theory.

  11. Cup Cylindrical Waveguide Antenna

    Science.gov (United States)

    Acosta, Roberto J.; Darby, William G.; Kory, Carol L.; Lambert, Kevin M.; Breen, Daniel P.

    2008-01-01

    The cup cylindrical waveguide antenna (CCWA) is a short backfire microwave antenna capable of simultaneously supporting the transmission or reception of two distinct signals having opposite circular polarizations. Short backfire antennas are widely used in mobile/satellite communications, tracking, telemetry, and wireless local area networks because of their compactness and excellent radiation characteristics. A typical prior short backfire antenna contains a half-wavelength dipole excitation element for linear polarization or crossed half-wavelength dipole elements for circular polarization. In order to achieve simultaneous dual circular polarization, it would be necessary to integrate, into the antenna feed structure, a network of hybrid components, which would introduce significant losses. The CCWA embodies an alternate approach that entails relatively low losses and affords the additional advantage of compactness. The CCWA includes a circular cylindrical cup, a circular disk subreflector, and a circular waveguide that serves as the excitation element. The components that make it possible to obtain simultaneous dual circular polarization are integrated into the circular waveguide. These components are a sixpost polarizer and an orthomode transducer (OMT) with two orthogonal coaxial ports. The overall length of the OMT and polarizer (for the nominal middle design frequency of 2.25 GHz) is about 11 in. (approximately equal to 28 cm), whereas the length of a commercially available OMT and polarizer for the same frequency is about 32 in. (approximately equal to 81 cm).

  12. Anisotropic and nonlinear optical waveguides

    CERN Document Server

    Someda, CG

    1992-01-01

    Dielectric optical waveguides have been investigated for more than two decades. In the last ten years they have had the unique position of being simultaneously the backbone of a very practical and fully developed technology, as well as an extremely exciting area of basic, forefront research. Existing waveguides can be divided into two sets: one consisting of waveguides which are already in practical use, and the second of those which are still at the laboratory stage of their evolution. This book is divided into two separate parts: the first dealing with anisotropic waveguides, an

  13. Optical trimer: A theoretical physics approach to waveguide couplers

    CERN Document Server

    Stoffel, A; Rodríguez-Lara, B M

    2016-01-01

    We study electromagnetic field propagation through an ideal, passive, triangular three-waveguide coupler using a symmetry based approach to take advantage of the underlying $SU(3)$ symmetry. The planar version of this platform has proven valuable in photonic circuit design providing optical sampling, filtering, modulating, multiplexing, and switching. We show that a group-theory approach can readily provide a starting point for design optimization of the triangular version. Our analysis is presented as a practical tutorial on the use of group theory to study photonic lattices for those not familiar with abstract algebra methods. In particular, we study the equilateral trimer to show the relation of pearl-necklace arrays with the Discrete Fourier Transform due to their cyclic group symmetry, and the isosceles trimer to show its relation with the golden ratio and its ability to provide stable output at a single waveguide. We also study the propagation dependent case of an equilateral trimer that linearly increa...

  14. Optical waveguide Hamiltonians leading to step-2 difference equations

    Energy Technology Data Exchange (ETDEWEB)

    Rueda-Paz, Juvenal; Wolf, Kurt Bernardo, E-mail: bwolf@fis.unam.mx [Instituto de Ciencias Fisicas, Universidad Nacional Autonoma de Mexico, Av. Universidad s/n, Cuernavaca, Morelos 62251 (Mexico)

    2011-03-01

    We examine the evolution of an N-point signal produced and sensed at finite arrays of points transverse to a planar waveguide, within the framework of the finite quantization of geometric optics. In contradistinction to the common mechanical Hamiltonians (kinetic plus potential energy terms) the classical waveguide Hamiltonian is the square root of a difference of squares of the refractive index profile minus the optical momentum. The finitely quantized model requires the solution of the square eigenvalue and eigenfunction problem which leads to a step-two difference equation that contains two solutions and two signs of energy. We find the proper linear combinations to fit the Kravchuk functions of the finite oscillator model.

  15. Virtual display design using waveguide hologram in conical mounting configuration

    Science.gov (United States)

    Yan, Zhanjun; Li, Wenqiang; Zhou, Yongjun; Kang, Mingwu; Zheng, Zhenrong

    2011-09-01

    An improved virtual display is proposed by using a waveguide holographic configuration with two total internal reflection holographic gratings in conical mounting and two volume hologram in classical mounting recorded on a single transparent planar waveguide. Using this compact configuration, efficiency can be dramatically improved and assembly is easy to be realized. The main principle and the method of intensity uniformity control are present in the paper. The analysis and simulation results are also explained. The virtual display system design shows good optical performance with 25 deg. field of view, a large pupil about 43 mm, little distortion less than 1%, and low aberration. The configuration can be used to a portable or wearable display.

  16. Waveguide-integrated photonic crystal spectrometer with camera readout

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Fan; Shiue, Ren-Jye; Li, Luozhou; Nie, Jing; Harris, Nicholas C.; Chen, Edward H.; Schröder, Tim; Englund, Dirk, E-mail: englund@mit.edu [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139 (United States); Wan, Noel [Department of Physics, Columbia University, New York, New York 10027 (United States); Pervez, Nadia [Chromation Partners LLC, 18 Bridge Street Suite 2J, Brooklyn, New York 11201 (United States); Kymissis, Ioannis [Chromation Partners LLC, 18 Bridge Street Suite 2J, Brooklyn, New York 11201 (United States); Department of Electrical Engineering, Columbia University, New York, New York 10027 (United States)

    2014-08-04

    We demonstrate an infrared spectrometer based on waveguide-coupled nanocavity filters in a planar photonic crystal structure. The input light is coupled into the waveguide, from which spectral components are dropped into the cavities and radiated off-chip for detection on a commercial InGaAs camera. The spectrometer has a footprint of only 60 μm by 8 μm. The spectral resolution is about 1 nm in the operation bandwidth of 1522–1545 nm. By substituting the membrane material and structure parameters, this design can be easily extended into the visible regime and developed for a variety of highly efficient, miniature photonic applications.

  17. Erbium Doped Phosphate Glass For Optical Waveguide Amplifier

    Institute of Scientific and Technical Information of China (English)

    R.S.F.Wong; S.Q.Man; E.Y.B.Pun; P.S.Chung

    2000-01-01

    @@ Erbium (Er3+) doped phosphate glasses was prepared and the optical properties of these glasses were investigated. The emission parameters were calculated using the Judd-Ofelt treatment. The radiative lifetime of the 4I13/2 level is calculated to be 7.2ms. The fluorescence lifetime is measured to be 6ms, and the quantum efficiency is estimated to be 83%. Ion-exchanged optical waveguides were fabricated in these glasses by using pure KNO3 meet at 370℃, and diluted AgNO3 molten salt at 270℃. It was found that the lower temperature diluted AgNO3 molten salt is better for the ion exchange process. Planar waveguide with 5 modes at the 633nm and 2 modes at the 1550nm was demonstrated using the diluted AgNO3. Our results show that phosphate glass is a potential candidate for the 1.5μm optical amplifier device.

  18. Light losses from scattering in luminescent solar concentrator waveguides.

    Science.gov (United States)

    Breukers, Robert D; Smith, Gerald J; Stirrat, Hedley L; Swanson, Adam J; Smith, Trevor A; Ghiggino, Kenneth P; Raymond, Sebastiampillai G; Winch, Nicola M; Clarke, David J; Kay, Andrew J

    2017-04-01

    The reductions in the transmission of emission originating from a fluorophore dissolved in a polymer matrix due to light scattering were compared in two forms of planar waveguides used as luminescent solar concentrators: a thin film of poly(methylmethacrylate) (PMMA) spin-coated on a glass plate and a solid PMMA plate of the same dimensions. The losses attributable to light scattering encountered in the waveguide consisting of the thin film of polymer coated on a glass plate were not detectable within experimental uncertainty, whereas the losses in the solid polymer plate were significant. The losses in the solid plate are interpreted as arising from light-scattering centers comprising minute bubbles of vapor/gas, incomplete polymerization or water clusters that are introduced during or after the thermally induced polymerization process.

  19. Recent progress on arrayed-waveguide grating wavelength multiplexer

    Science.gov (United States)

    Hida, Yasuhiro

    2004-10-01

    An arrayed-waveguide grating (AWG) is an attractive device for use in a WDM network because it offers multi-channel operation, design flexibility and suitability for mass production. AWGs fabricated using silica-based planar lightwave circuit (PLC) technologies are excellent in terms of loss and long-term stability, and so are widely used in commercial DWDM systems. This paper reviews recent progress on the AWG as regards improving its performance, especially with a view to eliminating polarization sensitivity. It also describes large-scale and compact AWGs formed using high-index contrast waveguides and fiber-connection methods using spot size converters. The second half of the paper reviews recent studies on functional devices incorporating thermo-optic (TO) switches and variable optical attenuators (VOAs).

  20. Optical waveguide Hamiltonians leading to step-2 difference equations

    Science.gov (United States)

    Rueda-Paz, Juvenal; Wolf, Kurt Bernardo

    2011-03-01

    We examine the evolution of an N-point signal produced and sensed at finite arrays of points transverse to a planar waveguide, within the framework of the finite quantization of geometric optics. In contradistinction to the common mechanical Hamiltonians (kinetic plus potential energy terms) the classical waveguide Hamiltonian is the square root of a difference of squares of the refractive index profile minus the optical momentum. The finitely quantized model requires the solution of the square eigenvalue and eigenfunction problem which leads to a step-two difference equation that contains two solutions and two signs of energy. We find the proper linear combinations to fit the Kravchuk functions of the finite oscillator model.

  1. Absorption-reduced waveguide structure for efficient terahertz generation

    Energy Technology Data Exchange (ETDEWEB)

    Pálfalvi, L., E-mail: palfalvi@fizika.ttk.pte.hu [Institute of Physics, University of Pécs, Ifjúság ú. 6, 7624 Pécs (Hungary); Fülöp, J. A. [MTA-PTE High-Field Terahertz Research Group, Ifjúság ú. 6, 7624 Pécs (Hungary); Szentágothai Research Centre, University of Pécs, Ifjúság ú. 20, 7624 Pécs (Hungary); Hebling, J. [Institute of Physics, University of Pécs, Ifjúság ú. 6, 7624 Pécs (Hungary); MTA-PTE High-Field Terahertz Research Group, Ifjúság ú. 6, 7624 Pécs (Hungary); Szentágothai Research Centre, University of Pécs, Ifjúság ú. 20, 7624 Pécs (Hungary)

    2015-12-07

    An absorption-reduced planar waveguide structure is proposed for increasing the efficiency of terahertz (THz) pulse generation by optical rectification of femtosecond laser pulses with tilted-pulse-front in highly nonlinear materials with large absorption coefficient. The structure functions as waveguide both for the optical pump and the generated THz radiation. Most of the THz power propagates inside the cladding with low THz absorption, thereby reducing losses and leading to the enhancement of the THz generation efficiency by up to more than one order of magnitude, as compared with a bulk medium. Such a source can be suitable for highly efficient THz pulse generation pumped by low-energy (nJ-μJ) pulses at high (MHz) repetition rates delivered by compact fiber lasers.

  2. Low crosstalk Arrayed Waveguide Grating with Cascaded Waveguide Grating Filter

    Energy Technology Data Exchange (ETDEWEB)

    Deng Yang; Liu Yuan; Gao Dingshan, E-mail: dsgao@mail.hust.edu.cn [Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2011-02-01

    We propose a highly compact and low crosstalk arrayed waveguide grating (AWG) with cascaded waveguide grating (CWGF). The side lobes of the silicon nanowire AWG, which are normally introduced by fabrication errors, can be effectively suppressed by the CWGF. And the crosstalk can be improved about 15dB.

  3. Realization of Tapered Waveguide by Stretching the Rod Waveguide

    Institute of Scientific and Technical Information of China (English)

    XIA Ke-yu; YU Rong-jin; MENG Hua-mao

    2004-01-01

    By stretching the rod waveguide with different velocities in opposite directions,the tapered waveguide can be fabricated.In condition of taking no account of volume expansion caused by heating and under the assumptions of volume conservation,the rod waveguide can be stretched freely in the heated region without being stretched outside of the heated region. A model,which shows the relation of the transition shape and the two factors,that is the ratio of two velocity and the heated region length,is presented for the shape of the taper transition through mathematic deduction.Based on this model,a desired tapered waveguide can be fabricated.The tapered waveguide are widely used for fabricating tapered fiber couplers and sensors.In addition,the conclusion can be used for fabricating fused fiber coupler.

  4. M-line spectroscopic, spectroscopic ellipsometric and microscopic measurements of optical waveguides fabricated by MeV-energy N{sup +} ion irradiation for telecom applications

    Energy Technology Data Exchange (ETDEWEB)

    Bányász, I., E-mail: banyasz@sunserv.kfki.hu [Wigner Research Centre for Physics, Hungarian Academy of Sciences, P.O.B. 49, H-1525, Budapest (Hungary); Berneschi, S. [“Enrico Fermi” Center for Study and Research, Piazza del Viminale 2, 00184 Roma (Italy); MDF-Lab, “Nello Carrara” Institute of Applied Physics, IFAC-CNR, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy); Fried, M.; Lohner, T. [Institute of Technical Physics and Materials Science, Research Centre for Natural Sciences, Hungarian Academy of Sciences, P.O.B. 49, H-1525, Budapest (Hungary); Conti, G. Nunzi; Righini, G.C.; Pelli, S. [MDF-Lab, “Nello Carrara” Institute of Applied Physics, IFAC-CNR, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy); Zolnai, Z. [Institute of Technical Physics and Materials Science, Research Centre for Natural Sciences, Hungarian Academy of Sciences, P.O.B. 49, H-1525, Budapest (Hungary)

    2013-08-31

    Irradiation with N{sup +} ions of the 1.5–3.5 MeV energy range was applied to optical waveguide formation. Planar and channel waveguides have been fabricated in an Er-doped tungsten–tellurite glass, and in both types of bismuth germanate (BGO) crystals: Bi{sub 4}Ge{sub 3}O{sub 12} (eulytine) and Bi{sub 12}GeO{sub 20} (sillenite). Multi-wavelength m-line spectroscopy and spectroscopic ellipsometry were used for the characterisation of the ion beam irradiated waveguides. Planar waveguides fabricated in the Er-doped tungsten–tellurite glass using irradiation with N{sup +} ions at 3.5 MeV worked even at the 1550 nm telecommunication wavelength. 3.5 MeV N{sup +} ion irradiated planar waveguides in eulytine-type BGO worked up to 1550 nm and those in sillenite-type BGO worked up to 1330 nm. - Highlights: ► Waveguides were fabricated in glass and crystals using MeV energy N{sup +} ions. ► SRIM simulation and spectroscopic ellipsometry yielded similar waveguide structures. ► Multi-wavelength m-line spectroscopy was used to study the waveguides. ► Waveguides fabricated in an Er-doped tungsten–tellurite glass worked up to 1.5 μm. ► Waveguides in Bi{sub 12}GeO{sub 20} remained operative up to 1.5 μm.

  5. Integrated polymer waveguides for absorbance detection in chemical analysis systems

    DEFF Research Database (Denmark)

    Mogensen, Klaus Bo; El-Ali, Jamil; Wolff, Anders

    2003-01-01

    . The emphasis of this paper is on the signal-to-noise ratio of the detection and its relation to the sensitivity. Two absorbance cells with an optical path length of 100 μm and 1000 μm were characterized and compared in terms of sensitivity, limit of detection and effective path length for measurements......A chemical analysis system for absorbance detection with integrated polymer waveguides is reported for the first time. The fabrication procedure relies on structuring of a single layer of the photoresist SU-8, so both the microfluidic channel network and the optical components, which include planar...

  6. Plasmonic finite-thickness metal-semiconductor-metal waveguide as ultra-compact modulator

    DEFF Research Database (Denmark)

    Babicheva, Viktoriia; Malureanu, Radu; Lavrinenko, Andrei

    2013-01-01

    electrical control of signal propagation. By pumping the core we can vary the gain level and thus the transmittance of the whole system. The study of the device was made using both analytical approaches for planar two-dimensional case as well as numerical simulations for finite-width waveguides. We analyze...... the eigenmodes of the F-MSM waveguide, propagation constant, confinement factor, Purcell factor, absorption coefficient, and extinction ratio of the structure. We show that using thin metal layers instead of thick ones we can obtain higher extinction ratio of the device....

  7. Quantum Computations with Transverse Modes of an Optical Field Propagating in Waveguides

    Institute of Scientific and Technical Information of China (English)

    符建; 唐少芳

    2003-01-01

    A fully optical method to perform quantum computation with transverse modes of the optical field propagating in waveguide is proposed by supplying the prescriptions for a universal set of quantum gates. The proposal for quantum computation is based on implementing a quantum bit with two normal modes of multi-mode waveguides. The proposed C-NOT gate has the potential of being more compact and easily realized than some optical implementations, since it is based on planar lightwave circuit technology and can be constructed by using Mach-Zehnder interferometer having semiconductor optical amplifiers with very large refractive nonlinearity in its arms.

  8. Two-axis tracking using translation stages for a lens-to-channel waveguide solar concentrator.

    Science.gov (United States)

    Liu, Yuxiao; Huang, Ran; Madsen, Christi K

    2014-10-20

    A two-axis tracking scheme designed for concentration realized by a single-axis mechanical tracker and a translation stage is discussed. The translation stage is used for adjusting positions for seasonal sun movement. It has two-dimensional x-y tracking instead of horizontal movement x-only. This tracking method is compatible with planar waveguide solar concentrators. A prototype system with 50x concentration shows >75% optical efficiency throughout the year in simulation and >65% efficiency experimentally. This efficiency can be further improved by the use of anti-reflection layers and a larger waveguide refractive index.

  9. Periodically multilayered planar optical concentrator for photovoltaic solar cells

    Science.gov (United States)

    Solano, Manuel E.; Faryad, Muhammad; Monk, Peter B.; Mallouk, Thomas E.; Lakhtakia, Akhlesh

    2013-11-01

    A planar optical concentrator comprising a periodic multilayered isotropic dielectric material backed by a metallic surface-relief grating was theoretically examined for silicon photovoltaics. The concentrator was optimized using a differential evolution algorithm for solar-spectrum-integrated power-flux density. Further optimization was carried out for tolerance to variations in the incidence angle, spatial dimensions, and dielectric properties. The average electron-hole pair density in a silicon solar cell can be doubled, and the material costs substantially diminished by this concentrator, whose efficacy is due to the excitation of waveguide modes and multiple surface-plasmon-polariton waves in a broad spectral regime.

  10. Periodically multilayered planar optical concentrator for photovoltaic solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Solano, Manuel E.; Monk, Peter B. [Department of Mathematical Sciences, University of Delaware, Newark, Delaware 19716 (United States); Faryad, Muhammad; Lakhtakia, Akhlesh, E-mail: akhlesh@psu.edu [Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Mallouk, Thomas E. [Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

    2013-11-04

    A planar optical concentrator comprising a periodic multilayered isotropic dielectric material backed by a metallic surface-relief grating was theoretically examined for silicon photovoltaics. The concentrator was optimized using a differential evolution algorithm for solar-spectrum-integrated power-flux density. Further optimization was carried out for tolerance to variations in the incidence angle, spatial dimensions, and dielectric properties. The average electron-hole pair density in a silicon solar cell can be doubled, and the material costs substantially diminished by this concentrator, whose efficacy is due to the excitation of waveguide modes and multiple surface-plasmon-polariton waves in a broad spectral regime.

  11. Hollow waveguide cavity ringdown spectroscopy

    Science.gov (United States)

    Dreyer, Chris (Inventor); Mungas, Greg S. (Inventor)

    2012-01-01

    Laser light is confined in a hollow waveguide between two highly reflective mirrors. This waveguide cavity is used to conduct Cavity Ringdown Absorption Spectroscopy of loss mechanisms in the cavity including absorption or scattering by gases, liquid, solids, and/or optical elements.

  12. Planar, monolithically integrated coil

    NARCIS (Netherlands)

    Roozeboom, F.; Reefman, D.; Klootwijk, J.H.; Tiemeijer, L.F.; Ruigrok, J.

    2013-01-01

    The present invention provides a means to integrate planar coils on silicon, while providing a high inductance. This high inductance is achieved through a special back- and front sided shielding of a material. In many applications, high-value inductors are a necessity. In particular, this holds for

  13. Complex Planar Splines.

    Science.gov (United States)

    1981-05-01

    try todefine a complex planar spline by holomorphic elements like polynomials, then by the well known identity theorem (e.g. Diederich- Remmert [9, p...R. Remmert : Funktionentheorie I, Springer, Berlin, Heidelberg, New York, 1972, 246 p. 10 0. Lehto - K.I. Virtanen: Quasikonforme AbbildunQen, Springer

  14. UWB planar antenna technology

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Recent developments of the ultra-wideband(UWB)planar antennas are reviewed,where the progress in UWB plate monopole antennas,UWB printed monopole antennas and the UWB printed slot antennas is introduced and compared.In addition,the UWB printed antennas with the band-notched functions are also presented.

  15. Optical waveguides in LiNbO3 and stoichiometric LiNbO3 crystals by proton exchange

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The formation of optical planar waveguides in LiNbO3 and stoichiometric LiNbO3 crystals by proton exchange was reported. The prism-coupling method was used to characterize the dark-line spectroscopy at the wavelength of 633 and 1539 nm, re-spectively. The mode optical near-field outputs from proton-exchanged LiNbO3 and SLN waveguides at 633 nm were presented. The mode field from stoichiometric LiNbO3 (SLN) waveguide is lighter and more uniform than that from LiNbO3 waveguide, which means the quality of the waveguide in SLN crystal is better than that of the LiNbO3 waveguide. For proton-exchanged LiNbO3 waveguides, the evo-lution of the refractive index profile with annealing was presented. The disorder profiles of Nb atoms in proton-exchanged LiNbO3 waveguides were obtained by Rutherford backscattering/channeling technique. It is shown that the longer the exchange time, the larger the displacement of Nb atoms.

  16. Actively coupled optical waveguides

    OpenAIRE

    Alexeeva, N. V.; Barashenkov, I. V.; Rayanov, K.; Flach, S.

    2013-01-01

    We consider light propagation through a pair of nonlinear optical waveguides with absorption, placed in a medium with power gain. The active medium boosts the in-phase component of the overlapping evanescent fields of the guides, while the nonlinearity of the guides couples it to the damped out-of-phase component creating a feedback loop. As a result, the structure exhibits stable stationary and oscillatory regimes in a wide range of gain-loss ratios. We show that the pair of actively-coupled...

  17. Rare-earth-ion doped KY(WO4)2 optical waveguides grown by liquid-phase epitaxy

    NARCIS (Netherlands)

    Romanyuk, Y.E.; Apostolopoulos, V.; Utke, U.; Pollnau, Markus

    2004-01-01

    High-quality KY(WO4)2 thin layers doped with rare-earth-ions were grown using liquid-phase epitaxy. A low-temperature mixture of chlorides was used as the flux and undoped KY(WO4)2 crystals as substrates. The crystalline layers possessed thicknesses up to 10 µm. Passive and active planar waveguiding

  18. Extensions to the quasi-static expressions for the line parameters of coplanar waveguide with relatively thick conductors

    Science.gov (United States)

    Co-planar waveguide (CPW) transmission line can be configured as a sensor to measure the complex permittivity of biological materials. By placing a material with unknown permittivity on the CPW and measuring the scattering parameters with a vector network analyzer, the characteristic impedance and e...

  19. Performance changes of a grated waveguide at resonance wavelengths next to its band-edges due to modified edge sections

    NARCIS (Netherlands)

    Alatas, H.; Iskandar, Alexander A.; Hoekstra, Hugo; Tjia, May-On

    2010-01-01

    An efficient numerical scheme developed on the basis of Green’s function method is applied to the investigation of structural effects on the performance of planar grated waveguide at the first resonance wavelengths next to the band-edges. Restricting ourselves to the transverse-electric waves, this

  20. Simultaneous 2D Strain Sensing Using Polymer Planar Bragg Gratings

    Directory of Open Access Journals (Sweden)

    Manuel Rosenberger

    2015-02-01

    Full Text Available We demonstrate the application of polymer planar Bragg gratings for multi-axial strain sensing and particularly highlight simultaneous 2D strain measurement. A polymer planar Bragg grating (PPBG fabricated with a single writing step in bulk polymethylmethacrylate is used for measuring both tensile and compressive strain at various angles. It is shown that the sensitivity of the PPBG strongly depends on the angle between the optical waveguide into which the grating is inscribed and the direction along which the mechanical load is applied. Additionally, a 2D PPBG fabricated by writing two Bragg gratings angularly displaced from each other into a single polymer platelet is bonded to a stainless steel plate. The two reflected wavelengths exhibit different sensitivities while tested toward tensile and compressive strain. These characteristics make 2D PPBG suitable for measuring multi-axial tensile and compressive strain.

  1. Preparation of transition metal nanoparticles and surfaces modified with (co)polymers synthesized by RAFT

    Science.gov (United States)

    McCormick, III, Charles L.; Lowe, Andrew B.; Sumerlin, Brent S.

    2011-12-27

    A new, facile, general one-phase method of generating thiol-functionalized transition metal nanoparticles and surfaces modified by (co)polymers synthesized by the RAFT method is described. The method includes the steps of forming a (co)polymer in aqueous solution using the RAFT methodology, forming a colloidal transition metal precursor solution from an appropriate transition metal; adding the metal precursor solution or surface to the (co)polymer solution, adding a reducing agent into the solution to reduce the metal colloid in situ to produce the stabilized nanoparticles or surface, and isolating the stabilized nanoparticles or surface in a manner such that aggregation is minimized. The functionalized surfaces generated using these methods can further undergo planar surface modifications, such as functionalization with a variety of different chemical groups, expanding their utility and application.

  2. A Microfluidic Device with an Integrated Waveguide Beam Splitter for Velocity Measurements of Flowing Particles by Fourier Transformation

    DEFF Research Database (Denmark)

    Mogensen, Klaus Bo; Kwok, Y.C.; Eijkel, J.C.T.

    2003-01-01

    A microfabricated capillary electrophoresis device for velocity measurements of flowing particles is presented. It consists of a 1 x 128 planar waveguide beam splitter monolithically integrated with an electrically insulated fluidic channel network for fluorescence excitation at multiple points...... optics. The integrated planar waveguide beam splitter was, furthermore, permanently connected to the light source by a glued-on optical fiber, to achieve a robust and alignment-free operation of the system. The velocity was measured using a Fourier transformation with a Shah function, since the response...... of the fight array was designed to approximate a square profile. Deviations from this response were observed as a result of the multimode nature of the integrated waveguides....

  3. Membrane-type photonic integration of InGaN/GaN multiple-quantum-well diodes and waveguide

    Science.gov (United States)

    Gao, Xumin; Bai, Dan; Cai, Wei; Xu, Yin; Yuan, Jialei; Yang, Yongchao; Zhu, Guixia; Cao, Xun; Zhu, Hongbo; Wang, Yongjin

    2017-02-01

    We report here a membrane-type integration of InGaN/GaN multiple-quantum-well diodes (MQWDs) with a waveguide to build a highly integrated photonic system to perform functionalities on a GaN-on-silicon platform. Suspended MQWDs can be used as either for light-emitting diode (LED) or photodiode. In the fabricated photonic system, part of the LED emission is coupled into a suspended waveguide, and the guided light laterally propagates along the waveguide and is finally sensed by the photodiode. The photonic system can detect the in-plane guided light and the external incident light simultaneously. Planar optical communication experimentally demonstrates that the proof-of-concept monolithic photonic integration system can achieve the in-plane visible light communication. This work paves the way towards novel active electro-optical sensing systems and planar optical communication in the visible range.

  4. Analysis of birefringence in magneto-optical waveguides based on nanoparticles doped sol–gel matrix with an optimized substrate

    Energy Technology Data Exchange (ETDEWEB)

    Lebbal, M.R., E-mail: Lebbalmohamedredha@yahoo.fr; Boumaza, T.; Bouchemat, M.

    2015-01-01

    The elimination of birefringence remains a key challenge in integrated optical systems. In this work, we present birefringence study based on the controlling of layer thickness of planar waveguides, using deposited layers based on magnetic nanoparticles. The birefringence can be reduced with a planar device, depending on a glass substrate. The simulation carried out by MATLAB allowed us to deduce the conditions to decrease the phase mismatch and increase the conversion ratio of modes. - Highlights: • We simulate the birefringence in isotropic and anisotropic waveguides. • The perpendicularly applied gelation field is very promising in decreasing the birefringence. • It is very promising to use the glass substrate and adjust the thin layer thickness. • The glass substrate contributes in increasing the range of mono-mode waveguide. • The optimal thickness is taken close to the cut-off thickness of the 2nd mode TE.

  5. High-index-contrast multilayer hollow waveguides for mid-IR laser delivery

    Science.gov (United States)

    Melzer, Jeffrey E.; Kendall, Wesley Y.; Harrington, James A.

    2016-03-01

    Hollow glass waveguides (HGWs) have been researched extensively for the efficient transmission of radiation over a broad spectral range spanning from the visible region to the far-IR. One such HGW film structure consists of a metallic substrate with overlaying multilayer dielectric thin film stack of alternating high and low refractive index films. The optical properties of such multilayer thin film stacks are well established and provide a method for developing photonic bandgap fibers with exceptionally low attenuation losses at a desired wavelength. Transmission losses can be minimized in multilayer waveguides through two main approaches; either maximizing the number of alternating layer pairs or maximizing the index contrast between adjacent films. In practice, it has been shown that for liquid-phase deposition-based procedures, the former approach leads to compounding surface and interface roughness, negating the low-loss advantage of a multilayer waveguide. Thus, this research focuses on maximizing index contrast between adjacent dielectrics in an attempt to minimize the number of films required to achieve acceptable transmission characteristics both in theory and in practice. In this study, multilayer waveguides are fabricated using three dielectric materials: silver iodide, lead sulfide, and cyclic olefin copolymer. Through exploitation of their high index contrast, these materials are used to develop low-film-count multilayer waveguides designed for enhanced transmission at both Er:YAG and CO2 laser wavelengths.

  6. Near-field characterization of plasmonic waveguides

    DEFF Research Database (Denmark)

    Zenin, Volodymyr

    2014-01-01

    This PhD thesis presents investigation of plasmonic waveguides and waveguiding components by means of scanning near-field optical microscopy characterizations, far-field optical observations, and numerical simulations. The plasmonic waveguiding attracts huge interest due to several reasons: 1...... simply by changing geometric parameters of the waveguide, keeping in mind the trade-off between confinement and propagation losses. A broad variety of plasmonic waveguides and waveguide components, including antennas for coupling the light in/out of the waveguide, requires correspondent characterization...

  7. Photorefractive properties of ion-implanted waveguides in strontium barium niobate crystals

    Science.gov (United States)

    Kip, D.; Kemper, B.; Nee, I.; Pankrath, R.; Moretti, P.

    1997-10-01

    Planar optical waveguides were formed in cerium-doped strontium barium niobate single crystals (Sr0.61Ba0.39Nb2O6, SBN61), either by proton or helium ion implantation. Proton-implanted samples show a large increase of dark conductivity that reduces or even prevents the recording of refractive index gratings. For waveguides formed by helium implantation this effect is absent, and they can be used for efficient holographic recording. Photorefractive properties of the waveguides are investigated by two-beam coupling. After implantation with 2.0 MeV He+ and doses of (0.5-5)񺔗 cm-2, the samples have to be polarized again, because heating or charge effects at the crystals surface during the implantation process decreases or even reverses the effective electrooptic coefficients in the waveguiding layer. For repoled samples, we find logarithmic gain coefficients of up to 45 cm-1 with time constants for the build-up of the purely ?/2-shifted refractive index grating of the order of 1 ms for the blue lines of an Ar+ laser. Photoconductivity depends nonlinearly on light intensity with an exponent xƸ.55. With increasing implanted helium dose, both electronic and nuclear damage of the waveguiding layer grows, and the photorefractive properties of the waveguides are considerably degraded.

  8. Capillary Array Waveguide Amplified Fluorescence Detector for mHealth.

    Science.gov (United States)

    Balsam, Joshua; Bruck, Hugh Alan; Rasooly, Avraham

    2013-09-01

    Mobile Health (mHealth) analytical technologies are potentially useful for carrying out modern medical diagnostics in resource-poor settings. Effective mHealth devices for underserved populations need to be simple, low cost, and portable. Although cell phone cameras have been used for biodetection, their sensitivity is a limiting factor because currently it is too low to be effective for many mHealth applications, which depend on detection of weak fluorescent signals. To improve the sensitivity of portable phones, a capillary tube array was developed to amplify fluorescence signals using their waveguide properties. An array configured with 36 capillary tubes was demonstrated to have a ~100X increase in sensitivity, lowering the limit of detection (LOD) of mobile phones from 1000 nM to 10 nM for fluorescein. To confirm that the amplification was due to waveguide behavior, we coated the external surfaces of the capillaries with silver. The silver coating interfered with the waveguide behavior and diminished the fluorescence signal, thereby proving that the waveguide behavior was the main mechanism for enhancing optical sensitivity. The optical configuration described here is novel in several ways. First, the use of capillaries waveguide properties to improve detection of weak florescence signal is new. Second we describe here a three dimensional illumination system, while conventional angular laser waveguide illumination is spot (or line), which is functionally one-dimensional illumination, can illuminate only a single capillary or a single column (when a line generator is used) of capillaries and thus inherently limits the multiplexing capability of detection. The planar illumination demonstrated in this work enables illumination of a two dimensional capillary array (e.g. x columns and y rows of capillaries). In addition, the waveguide light propagation via the capillary wall provides a third dimension for illumination along the axis of the capillaries. Such an

  9. Planar electrochemical device assembly

    Science.gov (United States)

    Jacobson, Craig P.; Visco, Steven J.; De Jonghe, Lutgard C.

    2007-06-19

    A pre-fabricated electrochemical device having a dense electrolyte disposed between an anode and a cathode preferably deposited as thin films is bonded to a porous electrically conductive support. A second porous electrically conductive support may be bonded to a counter electrode of the electrochemical device. Multiple electrochemical devices may be bonded in parallel to a single porous support, such as a perforated sheet to provide a planar array. Planar arrays may be arranged in a stacked interconnected array. A method of making a supported electrochemical device is disclosed wherein the method includes a step of bonding a pre-fabricated electrochemical device layer to an existing porous metal or porous metal alloy layer.

  10. Planar Hall Effect MRAM

    OpenAIRE

    Bason, Y.; Klein, L.; Yau, J. -B.; Hong, X.; Hoffman, J.; Ahn, C. H.

    2005-01-01

    We suggest a new type of magnetic random access memory (MRAM) that is based on the phenomenon of the planar Hall effect (PHE) in magnetic films, and we demonstrate this idea with manganite films. The PHE-MRAM is structurally simpler than currently developed MRAM that is based on magnetoresistance tunnel junctions (MTJ), with the tunnel junction structure being replaced by a single layer film.

  11. Routed planar networks

    Directory of Open Access Journals (Sweden)

    David J. Aldous

    2016-04-01

    Full Text Available Modeling a road network as a planar graph seems very natural. However, in studying continuum limits of such networks it is useful to take {\\em routes} rather than {\\em edges} as primitives. This article is intended to introduce the relevant (discrete setting notion of {\\em routed network} to graph theorists. We give a naive classification of all 71 topologically different such networks on 4 leaves, and pose a variety of challenging research questions.

  12. Grating-Coupled Waveguide Cloaking

    Institute of Scientific and Technical Information of China (English)

    WANG Jia-Fu; QU Shao-Bo; XU Zhuo; MA Hua; WANG Cong-Min; XIA Song; WANG Xin-Hua; ZHOU Hang

    2012-01-01

    Based on the concept of a grating-coupled waveguide (GCW),a new strategy for realizing EM cloaking is presented.Using metallic grating,incident waves are firstly coupled into the effective waveguide and then decoupled into free space behind,enabling EM waves to pass around the obstacle.Phase compensation in the waveguide keeps the wave-front shape behind the obstacle unchanged.Circular,rectangular and triangular cloaks are presented to verify the robustness of the GCW cloaking.Electric field animations and radar cross section (RCS)comparisons convincingly demonstrate the cloaking effect.

  13. Hollow waveguide for urology treatment

    Science.gov (United States)

    Jelínková, H.; Němec, M.; Koranda, P.; Pokorný, J.; Kőhler, O.; Drlík, P.; Miyagi, M.; Iwai, K.; Matsuura, Y.

    2010-02-01

    The aim of our work was the application of the special sealed hollow waveguide system for the urology treatment - In our experimental study we have compared the effects of Ho:YAG (wavelength 2100 nm) and Er:YAG (wavelength 2940 nm) laser radiation both on human urinary stones (or compressed plaster samples which serve as a model) fragmentation and soft ureter tissue incision in vitro. Cyclic Olefin Polymer - coated silver (COP/Ag) hollow glass waveguides with inner and outer diameters 700 and 850 μm, respectively, were used for the experiment. To prevent any liquid to diminish and stop the transmission, the waveguide termination was utilized.

  14. Generalized Modal Analysis of Electromagnetic - and Quantum-Waveguide Structures and Discontinuities

    Science.gov (United States)

    Weisshaar, Andreas

    Generalized modal analysis techniques for the characterization and modeling of dissipationless planar waveguide structures and discontinuities encountered in microwave and optical integrated circuits, as well as of quantum waveguide structures and devices, are presented. The frequency-dependent transmission properties of the curved microstrip bend are derived by utilizing a second-order perturbation analysis of the equivalent modified curved waveguide model and a mode-matching method which includes the higher order modes. An extension of the mode-matching method for characterization of microstrip right-angle bends and T junctions having a rectangular notch is formulated. The modal solutions for an arbitrary graded-index dielectric slab waveguide are derived by applying the generalized telegraphist's equations to the equivalent inhomogeneous parallel-plate waveguide model with electric or magnetic walls. These modal solutions are employed in a mode-matching procedure to calculate the transmission properties of a step discontinuity in typical diffused optical dielectric slab waveguides. Power loss calculations for an abrupt offset in a diffused optical waveguide show a smooth increase in radiation loss whereas a sharp transition from almost zero to nearly total radiation loss is found for an abrupt change in diffusion depth. In the analysis of quantum waveguide structures, the modal expansions of the wave function together with a mode-matching technique are utilized. The computed generalized scattering matrices (GSMs) of junctions and uniform waveguide sections are combined via an extended GSM technique to obtain the scattering parameters of composite quantum waveguide structures. Results for cascaded right-angle bends and periodic multi-waveguide structures in a split-gate configuration are presented assuming hard wall confinement. For the multisection structures, strong resonant behavior similar to that in resonant tunneling diodes is found. Calculated current

  15. Mode Characterization for Planar and Corrugated Multilayer Structures via Scattering Matrix Analysis

    CERN Document Server

    Kneale, Casey; Booksh, Karl S

    2016-01-01

    The construction of the unconditionally stable planar rank 2 scattering matrix for stratified systems is detailed from Fresnel equations. Several matrix decompositions and numerical calculations performed on the planar S matrix allow for the expedient characterization of purely absorbing, brewster, surface plasmon, and wave-guide modes. A figure of merit is presented from the decompositions of the scattering matrix constructed from the Chandezon method for corrugated surfaces. This figure of merit represents the hyper-area of the scattering matrix transform and allows for rapid distinguishability between lossy absorption phenomena, and surface plasmons. Some extension of this technique is possible for surface plasmon polaritons in the infrared region.

  16. Evanescent cultivation of photosynthetic bacteria on thin waveguides

    Science.gov (United States)

    Pierobon, S. C.; Ooms, M. D.; Sinton, D.

    2014-04-01

    Waveguides with thicknesses similar to biofilms (10-100 µm) provide an opportunity to improve the bioenergy density of biofilm photobioreactors, avoiding the fundamental light- and mass-transport productivity limitations of planktonic photobioreactors. This report investigates the biofilm growth of a mutant of Synechococcus elongatus (PCC 7942) in evanescent light fields that can be scaled over large planar areas. In this study, areas of 7.2 cm2 are illuminated via frustrated total internal reflections on planar waveguides. The resulting photosynthetic biofilm growth showed resilience to surface intensities exceeding photosynthetic limits and a more uniform cell density distribution (1.0 ± 0.3 × 109 mL-1) than predicted from surface light distribution profiles. These results indicate potential for larger area biofilms using the uniform lighting conditions identified. The combination of evanescent illumination with biofilms indicates a modular reactor cell density on the order of 108 mL-1, representing a two orders of magnitude improvement over current facility architectures, with significant potential for further improvement through denser biofilms.

  17. Plasma synthesis of rare earth doped integrated optical waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Raoux, S.; Anders, S.; Yu, K.M.; Brown, I.G. [Lawrence Berkeley Lab., CA (United States); Ivanov, I.C. [Charles Evans & Associates, Redwood City, CA (United States)

    1995-03-01

    We describe a novel means for the production of optically active planar waveguides. The makes use of a low energy plasma deposition. Cathodic-arc-produced metal plasmas the metallic components of the films and gases are added to form compound films. Here we discuss the synthesis of Al{sub 2{minus}x}ER{sub x}O{sub 3} thin films. The erbium concentration (x) can vary from 0 to 100% and the thickness of the film can be from Angstroms to microns. In such material, at high active center concentration (x=l% to 20%), erbium ions give rise to room temperature 1.53{mu}m emission which has minimum loss in silica-based optical fibers. With this technique, multilayer integrated planar waveguide structures can be grown, such as Al{sub 2}O{sub 3}/Al{sub 2{minus}x}Er{sub x}O{sub 3}/Al{sub 2}O{sub 3}/Si, for example.

  18. Fabrication of channel waveguides from sol-gel-processed polyvinylpyrrolidone/ SiO(2) composite materials.

    Science.gov (United States)

    Yoshida, M; Prasad, P N

    1996-03-20

    Sol-gel-processed composite materials of polyvinylpyrrolidone (PVP) and SiO(2) were studied for optical waveguide applications. PVP is a polymer that can be crosslinked, so it is expected to have high thermal stability after crosslinking. However, thermal crosslinking and thermal decomposition of pure PVP take place around the same temperature, 200 °C, therefore pure PVP had a high optical propagation loss as a result of the absorption of the decomposed molecules after crosslinking. The incorporation of sol-gel-processed SiO(2) prevented the thermal decomposition of PVP and provided remarkably low optical propagation losses. The PVP/SiO(2)composite material also produced thick (>2-µm) crack-free films when the PVP concentration was 50% or higher. An optical propagation loss of 0.2 dB/cm was achieved at 633 nm in the 50% PVP/SiO(2) composite planar waveguide. Several aspects of the thermal stability of the waveguides were evaluated. The slab waveguide was then used for fabrication of channel waveguides with a selective laser-densification technique. This technique used metal lines fabricated with photolithography on the slab waveguide as a light absorbent, and these metal lines were heated by an Ar laser. The resultant channel waveguide had an optical propagation loss of 0.9 dB/ cm at 633 nm. This technique provides lower absorption loss and scattering loss compared with the direct laser-densification technique, which uses UV lasers, and produces narrow waveguides that are difficult to fabricate with a CO(2) laser.

  19. Complete power concentration into a single waveguide in large-scale waveguide array lenses.

    Science.gov (United States)

    Catrysse, Peter B; Liu, Victor; Fan, Shanhui

    2014-10-16

    Waveguide array lenses are waveguide arrays that focus light incident on all waveguides at the input side into a small number of waveguides at the output side. Ideal waveguide array lenses provide complete (100%) power concentration of incident light into a single waveguide. While of great interest for several applications, ideal waveguide array lenses have not been demonstrated for practical arrays with large numbers of waveguides. The only waveguide arrays that have sufficient degrees of freedom to allow for the design of an ideal waveguide array lens are those where both the propagation constants of the individual waveguides and the coupling constants between the waveguides vary as a function of space. Here, we use state-of-the-art numerical methods to demonstrate complete power transfer into a single waveguide for waveguide array lenses with large numbers of waveguides. We verify this capability for more than a thousand waveguides using a spatial coupled mode theory. We hereby extend the state-of-art by more than two orders of magnitude. We also demonstrate for the first time a physical design for an ideal waveguide array lens. The design is based on an aperiodic metallic waveguide array and focuses ~100% of the incident light into a deep-subwavelength focal spot.

  20. Reflectively Coupled Waveguide Photodetector for High Speed Optical Interconnection

    Directory of Open Access Journals (Sweden)

    Shih-Hsiang Hsu

    2010-12-01

    Full Text Available To fully utilize GaAs high drift mobility, techniques to monolithically integrate In0.53Ga0.47As p-i-n photodetectors with GaAs based optical waveguides using total internal reflection coupling are reviewed. Metal coplanar waveguides, deposited on top of the polyimide layer for the photodetector’s planarization and passivation, were then uniquely connected as a bridge between the photonics and electronics to illustrate the high-speed monitoring function. The photodetectors were efficiently implemented and imposed on the echelle grating circle for wavelength division multiplexing monitoring. In optical filtering performance, the monolithically integrated photodetector channel spacing was 2 nm over the 1,520–1,550 nm wavelength range and the pass band was 1 nm at the −1 dB level. For high-speed applications the full-width half-maximum of the temporal response and 3-dB bandwidth for the reflectively coupled waveguide photodetectors were demonstrated to be 30 ps and 11 GHz, respectively. The bit error rate performance of this integrated photodetector at 10 Gbit/s with 27-1 long pseudo-random bit sequence non-return to zero input data also showed error-free operation.

  1. Low-loss as-grown germanosilicate layers for optical waveguides

    Science.gov (United States)

    Ay, Feridun; Aydinli, Atilla; Agan, Sedat

    2003-12-01

    We report on systematic growth and characterization of low-loss germanosilicate layers for use in optical waveguide technology. The films were deposited by plasma-enhanced chemical vapor deposition technique using silane, germane, and nitrous oxide as precursor gases. Fourier transform infrared spectroscopy was used to monitor the compositional properties of the samples. It was found that addition of germane leads to decreasing of N-H- and O-H-related bonds. The propagation loss values of the planar waveguides were correlated with the decrease in the hydrogen-related bonds of the as-deposited waveguides and resulted in very low values, eliminating the need for high-temperature annealing as is usually done.

  2. Hypersingular integral equations, waveguiding effects in Cantorian Universe and genesis of large scale structures

    Energy Technology Data Exchange (ETDEWEB)

    Iovane, G. [Dipartimento di Ingegneria, dell' Informazione e Matematica Applicata, Universita di Salerno, Salerno (Italy)] e-mail: iovane@diima.unisa.it; Giordano, P. [Dipartimento di Ingegneria, dell' Informazione e Matematica Applicata, Universita di Salerno, Salerno (Italy)

    2005-08-01

    In this work we introduce the hypersingular integral equations and analyze a realistic model of gravitational waveguides on a cantorian space-time. A waveguiding effect is considered with respect to the large scale structure of the Universe, where the structure formation appears as if it were a classically self-similar random process at all astrophysical scales. The result is that it seems we live in an El Naschie's o {sup ({infinity})} Cantorian space-time, where gravitational lensing and waveguiding effects can explain the appearing Universe. In particular, we consider filamentary and planar large scale structures as possible refraction channels for electromagnetic radiation coming from cosmological structures. From this vision the Universe appears like a large self-similar adaptive mirrors set, thanks to three numerical simulations. Consequently, an infinite Universe is just an optical illusion that is produced by mirroring effects connected with the large scale structure of a finite and not a large Universe.

  3. Design of a Label-Free, Distributed Bragg Grating Resonator Based Dielectric Waveguide Biosensor

    Directory of Open Access Journals (Sweden)

    Florian Kehl

    2015-01-01

    Full Text Available In this work, we present a resonant, dielectric waveguide device based on distributed Bragg gratings for label-free biosensing applications. The refractive index sensitive optical transducer aims at improving the performance of planar waveguide grating sensor systems with limited Q-factor and dynamic range by combing the advantages of resonant cavities, such as a multitude of resonance peaks with high finesse, with the manageable complexity of waveguide grating couplers. The general sensor concept is introduced and supported by theoretical considerations as well as numerical simulations based on Coupled Mode Theory. In contrast to a single Bragg grating reflector, the presented Fabry-Pérot type distributed Bragg resonator exhibits an extended measurement range as well as relaxed fabrication tolerances. The resulting, relatively simple sensor structure can be fabricated with standard lithographic means and is independent of expensive light-sources and/or detectors, making an affordable but sensitive device, potentially suitable for point-of-care applications.

  4. Optical Waveguide Property of Nd-doped Laser Materials Ndx Y1-x A13(BO3) 4 and Nd∶MgO∶LiNbO3

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Lanthanide has attracted much attention in the field of optical communications in recent years. Some property analyses on optical waveguide of Nd-doped crystal NdxY1-xA13(BO3)4 and Nd∶MgO∶LiNbO3 are made in this paper, followed by introduction of the methods of experimentation and theoretical calculation for the planar optical waveguides. The refractive index profiles of the optical waveguides are analyzed. The above work offers useful information for study on new type materials for optical communications.

  5. Diamond nanobeam waveguide optomechanics

    CERN Document Server

    Khanaliloo, Behzad; Hryciw, Aaron C; Lake, David P; Kaviani, Hamidreza; Barclay, Paul E

    2015-01-01

    Optomechanical devices sensitively transduce and actuate motion of nanomechanical structures using light, and are central to many recent fundamental studies and technological advances. Single--crystal diamond promises to improve the performance of optomechanical devices, while also providing opportunities to interface nanomechanics with diamond color center spins and related quantum technologies. Here we demonstrate measurement of diamond nanobeam resonators with a sensitivity of 9.5 fm/Hz^0.5 and bandwidth >120 nm through dissipative waveguide--optomechanical coupling. Nanobeams are fabricated from bulk single--crystal diamond using a scalable quasi--isotropic oxygen plasma undercut etching process, and support mechanical resonances with quality factor of 2.5 x 10^5 at room temperature, and 7.2 x 10^5 in cryogenic conditions (5K). Mechanical self--oscillations, resulting from interplay between optomechanical coupling and the photothermal response of nanobeams in a buckled state, are observed with amplitude e...

  6. Optical waveguide theory

    CERN Document Server

    Snyder, Allan W

    1983-01-01

    This text is intended to provide an in-depth, self-contained, treatment of optical waveguide theory. We have attempted to emphasize the underlying physical processes, stressing conceptual aspects, and have developed the mathematical analysis to parallel the physical intuition. We also provide comprehensive supplementary sections both to augment any deficiencies in mathematical background and to provide a self-consistent and rigorous mathematical approach. To assist in. understanding, each chapter con­ centrates principally on a single idea and is therefore comparatively short. Furthermore, over 150 problems with complete solutions are given to demonstrate applications of the theory. Accordingly, through simplicity of approach and numerous examples, this book is accessible to undergraduates. Many fundamental topics are presented here for the first time, but, more importantly, the material is brought together to give a unified treatment of basic ideas using the simplest approach possible. To achieve such a goa...

  7. Slow Light in Metamaterial Waveguides

    CERN Document Server

    Lavoie, Benjamin R

    2013-01-01

    Metamaterials, which are materials engineered to possess novel optical properties, have been increasingly studied. The ability to fabricate metamaterials has sparked an interest in determining possible applications. We investigate using a metamaterial for boundary engineering in waveguides. A metamaterial-clad cylindrical waveguide is used to provide confinement for an optical signal, thereby increasing the local electromagnetic energy density. We show that metamaterial-clad waveguides have unique optical properties, including new modes, which we call hybrid modes. These modes have properties of both ordinary guided modes and surface plasmon-polariton modes. We show that for certain metamaterial parameters, the surface plasmon-polariton modes of a metamaterial-clad waveguide have less propagation loss than those of a metal-clad guide with the same permittivity. This low-loss mode is exploited for all-optical control of weak fields. Embedding three-level {\\Lambda} atoms in the dielectric core of a metamaterial...

  8. Quantum mechanical description of waveguides

    Institute of Scientific and Technical Information of China (English)

    Wang Zhi-Yong; Xiong Cai-Dong; He Bing

    2008-01-01

    Applying the spinor representation of the electromagnetic field,this paper present a quantum-mechanical description of waveguides.As an example of application,a potential qubit generated by photon tunnelling is discussed.

  9. Planar integrated metasurfaces for highly-collimated terahertz quantum cascade lasers

    Science.gov (United States)

    Liang, Guozhen; Dupont, Emmanuel; Fathololoumi, Saeed; Wasilewski, Zbigniew R.; Ban, Dayan; Liang, Hou Kun; Zhang, Ying; Yu, Siu Fung; Li, Lianhe H.; Davies, Alexander Giles; Linfield, Edmund H.; Liu, Hui Chun; Wang, Qi Jie

    2014-01-01

    We report planar integration of tapered terahertz (THz) frequency quantum cascade lasers (QCLs) with metasurface waveguides that are designed to be spoof surface plasmon (SSP) out-couplers by introducing periodically arranged SSP scatterers. The resulting surface-emitting THz beam profile is highly collimated with a divergence as narrow as ~4° × 10°, which indicates a good waveguiding property of the metasurface waveguide. In addition, the low background THz power implies a high coupling efficiency for the THz radiation from the laser cavity to the metasurface structure. Furthermore, since all the structures are in-plane, this scheme provides a promising platform where well-established surface plasmon/metasurface techniques can be employed to engineer the emitted beam of THz QCLs controllably and flexibly. More importantly, an integrated active THz photonic circuit for sensing and communication applications could be constructed by incorporating other optoelectronic devices such as Schottky diode THz mixers, and graphene modulators and photodetectors. PMID:25403796

  10. Experimental Study on Near-IR Nonlinear Optical Waveguide Sensor for Refractive Index of Liquids

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jin-rong; WANG Dong; CAO Chang-xiu; ZHUANG Ling

    2007-01-01

    To determine the refractive index of liquids in near infrared(IR),a method is presented by measuring the output angle of the visible Cerenkov-radiation-mode when liquids are placed as the cover on a planar lithium niobate waveguide.The system configuration and the principle of the method are analyzed and some experimental results are given out.Both the experimental result and simulation show that this method is simple,rapid and of sufficient precision.

  11. Influence of coupling of dielectric waveguide and reflective grating on radiation characteristics

    OpenAIRE

    Steshenko, Sergiy O.

    2005-01-01

    Influence of the gap between the planar dielectric waveguide and the reflective grating on the radiation characteristics of the antenna of diffraction radiation has been investigated on the bases of the accurate two-dimensional model. It has been shown that decreasing of the gap does not necessarily result in increasing of the efficiency of conversion of the surface waves into spatial ones. Drastic change of the radiation characteristics in the saturation mode has been revealed.

  12. Dynamical manipulation of Cosine-Gauss beams in a graphene plasmonic waveguide.

    Science.gov (United States)

    He, Xueqing; Ning, Tigang; Li, Rujiang; Pei, Li; Zheng, Jingjing; Li, Jing

    2017-06-12

    In this paper, we theoretically propose for the first time that graphene monolayer can be used to manipulate the Cosine-Gauss beams (CGBs). We show that both the transverse oscillation period and propagation length of a CGB can be dynamically manipulated by utilizing the tunability of the graphene's chemical potential. The graphene-based planar plasmonic waveguide provides a good platform to investigate the propagation properties of CGBs, which is potentially compatible to the microelectronic technology.

  13. ZnO - Wide Bandgap Semiconductor and Possibilities of Its Application in Optical Waveguide Structures

    OpenAIRE

    Struk Przemysław; Pustelny Tadeusz; Gołaszewska Krystyna; A. Borysiewicz Michał; Kamińska Eliana; Wojciechowski Tomasz; Piotrowska Anna

    2014-01-01

    The paper presents the results of investigations concerning the application of zinc oxide - a wideband gap semiconductor in optical planar waveguide structures. ZnO is a promising semiconducting material thanks to its attractive optical properties. The investigations were focused on the determination of the technology of depositions and the annealing of ZnO layers concerning their optical properties. Special attention was paid to the determination of characteristics of the refractive index of...

  14. Broadband photonic crystal waveguide 60° bend obtained utilizing topology optimization

    DEFF Research Database (Denmark)

    Frandsen, Lars Hagedorn; Harpøth, Anders; Borel, Peter Ingo

    2004-01-01

    Topology optimization has been used to design a 60° bend in a single-mode planar photonic crystal waveguide. The design has been realized in a silicon-on-insulator material and we demonstrate a record-breaking 200-nm transmission bandwidth with an average bend loss of 0.43±0.27 dB for the TE...... polarization. The experimental results agree well with 3D finite-difference-time-domain simulations....

  15. BARRIER PROPERTIES OF VINYLIDENE CHLORIDE COPOLYMERS

    Institute of Scientific and Technical Information of China (English)

    LI Yuesheng; WENG Zhixue; HUANG Zhiming; PAN Zuren

    1996-01-01

    The permeability coefficients of a series of copolymers of vinylidene chloride (VDC)with methyl acrylate (MA), butyl acrylate (BA) or vinyl chloride (VC) (as comonomer)to oxygen and carbon dioxide have been measured at 1.0 MPa and 30℃, while those to water vapor have been measured at 30℃ and 100% relative humidity. All the copolymers are semicrystalline. VDC/MA copolymers have lower melting temperature compared with VDC/BA copolymers, while that melting temperature of VDC/VC copolymer is higher than that of VDC/acrylate copolymers with the same VDC content. The barrier property of the copolymers is predominantly controlled by crystallite, free volume fraction, and cohesive energy. The permeability coefficients of VDC/MA copolymers to oxygen, carbon dioxide, and water vapor were successfully correlated with the ratio of free volume to cohesive energy.

  16. Lignin poly(lactic acid) copolymers

    Energy Technology Data Exchange (ETDEWEB)

    Olsson, Johan Vilhelm; Chung, Yi-Lin; Li, Russell Jingxian; Waymouth, Robert; Sattely, Elizabeth; Billington, Sarah; Frank, Curtis W.

    2017-02-14

    Provided herein are graft co-polymers of lignin and poly(lactic acid) (lignin-g-PLA copolymer), thermoset and thermoplastic polymers including them, methods of preparing these polymers, and articles of manufacture including such polymers.

  17. Coupling Ideality of Integrated Planar High-Q Microresonators

    Science.gov (United States)

    Pfeiffer, Martin H. P.; Liu, Junqiu; Geiselmann, Michael; Kippenberg, Tobias J.

    2017-02-01

    Chip-scale optical microresonators with integrated planar optical waveguides are useful building blocks for linear, nonlinear, and quantum-optical photonic devices alike. Loss reduction through improving fabrication processes results in several integrated microresonator platforms attaining quality (Q ) factors of several millions. Beyond the improvement of the quality factor, the ability to operate the microresonator with high coupling ideality in the overcoupled regime is of central importance. In this regime, the dominant source of loss constitutes the coupling to a single desired output channel, which is particularly important not only for quantum-optical applications such as the generation of squeezed light and correlated photon pairs but also for linear and nonlinear photonics. However, to date, the coupling ideality in integrated photonic microresonators is not well understood, in particular, design-dependent losses and their impact on the regime of high ideality. Here we investigate design-dependent parasitic losses described by the coupling ideality of the commonly employed microresonator design consisting of a microring-resonator waveguide side coupled to a straight bus waveguide, a system which is not properly described by the conventional input-output theory of open systems due to the presence of higher-order modes. By systematic characterization of multimode high-Q silicon nitride microresonator devices, we show that this design can suffer from low coupling ideality. By performing 3D simulations, we identify the coupling to higher-order bus waveguide modes as the dominant origin of parasitic losses which lead to the low coupling ideality. Using suitably designed bus waveguides, parasitic losses are mitigated with a nearly unity ideality and strong overcoupling (i.e., a ratio of external coupling to internal resonator loss rate >9 ) are demonstrated. Moreover, we find that different resonator modes can exchange power through the coupler, which, therefore

  18. Perfect imaging with geodesic waveguides

    Science.gov (United States)

    Miñano, Juan C.; Benítez, Pablo; González, Juan C.

    2010-12-01

    Transformation optics is used to prove that a spherical waveguide filled with an isotropic material with radial refractive index n=1/r has radially polarized modes (i.e. the electric field is only radial) with the same perfect focusing properties as the Maxwell fish-eye (MFE) lens. An approximate version of that device, comprising a thin waveguide with a homogeneous core, paves the way to experimentally attaining perfect imaging in the MFE lens.

  19. Multiscaffold DNA Origami Nanoparticle Waveguides

    Science.gov (United States)

    2013-01-01

    DNA origami templated self-assembly has shown its potential in creating rationally designed nanophotonic devices in a parallel and repeatable manner. In this investigation, we employ a multiscaffold DNA origami approach to fabricate linear waveguides of 10 nm diameter gold nanoparticles. This approach provides independent control over nanoparticle separation and spatial arrangement. The waveguides were characterized using atomic force microscopy and far-field polarization spectroscopy. This work provides a path toward large-scale plasmonic circuitry. PMID:23841957

  20. UV-LIGA microfabrication process for sub-terahertz waveguides utilizing multiple layered SU-8 photoresist

    Science.gov (United States)

    Malekabadi, Ali; Paoloni, Claudio

    2016-09-01

    A microfabrication process based on UV LIGA (German acronym of lithography, electroplating and molding) is proposed for the fabrication of relatively high aspect ratio sub-terahertz (100-1000 GHz) metal waveguides, to be used as a slow wave structure in sub-THz vacuum electron devices. The high accuracy and tight tolerances required to properly support frequencies in the sub-THz range can be only achieved by a stable process with full parameter control. The proposed process, based on SU-8 photoresist, has been developed to satisfy high planar surface requirements for metal sub-THz waveguides. It will be demonstrated that, for a given thickness, it is more effective to stack a number of layers of SU-8 with lower thickness rather than using a single thick layer obtained at lower spin rate. The multiple layer approach provides the planarity and the surface quality required for electroforming of ground planes or assembly surfaces and for assuring low ohmic losses of waveguides. A systematic procedure is provided to calculate soft and post-bake times to produce high homogeneity SU-8 multiple layer coating as a mold for very high quality metal waveguides. A double corrugated waveguide designed for 0.3 THz operating frequency, to be used in vacuum electronic devices, was fabricated as test structure. The proposed process based on UV LIGA will enable low cost production of high accuracy sub-THz 3D waveguides. This is fundamental for producing a new generation of affordable sub-THz vacuum electron devices, to fill the technological gap that still prevents a wide diffusion of numerous applications based on THz radiation.

  1. ZnO - Wide Bandgap Semiconductor and Possibilities of Its Application in Optical Waveguide Structures

    Directory of Open Access Journals (Sweden)

    Struk Przemysław

    2014-08-01

    Full Text Available The paper presents the results of investigations concerning the application of zinc oxide - a wideband gap semiconductor in optical planar waveguide structures. ZnO is a promising semiconducting material thanks to its attractive optical properties. The investigations were focused on the determination of the technology of depositions and the annealing of ZnO layers concerning their optical properties. Special attention was paid to the determination of characteristics of the refractive index of ZnO layers and their coefficients of spectral transmission within the UV-VIS-NIR range. Besides that, also the mode characteristics and the attenuation coefficients of light in the obtained waveguide structures have been investigated. In the case of planar waveguides, in which the ZnO layers have not been annealed after their deposition, the values of the attenuation coefficient of light modes amount to a~ 30 dB/cm. The ZnO layers deposited on the heated substrate and annealed by rapid thermal annealing in an N2 and O2 atmosphere, are characterized by much lower values of the attenuation coefficients: a~ 3 dB/cm (TE0 and TM0 modes. The ZnO optical waveguides obtained according to our technology are characterized by the lowest values of the attenuation coefficients a encountered in world literature concerning the problem of optical waveguides based on ZnO. Studies have shown that ZnO layers elaborated by us can be used in integrated optic systems, waveguides, optical modulators and light sources.

  2. Vertical coupling of laser glass microspheres to buried silicon nitride ellipses and waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Navarro-Urrios, D., E-mail: daniel.navarrourrios@nano.cnr.it [NEST, Istituto Nanoscienze—CNR and Scuola Normale Superiore, Piazza San Silvestro 12, Pisa I-56127 (Italy); Ramírez, J. M.; Berencén, Y.; Garrido, B. [Departament d' Electrònica, Universitat de Barcelona, Barcelona 08028 (Spain); Capuj, N. E. [Depto. Física, Universidad de la Laguna, 38206, La Laguna (Spain); Tredicucci, A. [NEST, Istituto Nanoscienze and Dipartimento di Fisica, Università di Pisa, Largo Pontecorvo 3, Pisa I-56127 (Italy)

    2015-09-07

    We demonstrate the integration of Nd{sup 3+} doped barium-titanium-silicate microsphere lasers with a silicon nitride photonic platform. Devices with two different geometrical configurations for extracting the laser light to buried waveguides have been fabricated and characterized. The first configuration relies on a standard coupling scheme, where the microspheres are placed over strip waveguides. The second is based on a buried elliptical geometry whose working principle is that of an elliptical mirror. In the latter case, the input of a strip waveguide is placed on one focus of the ellipse, while a lasing microsphere is placed on top of the other focus. The fabricated elliptical geometry (ellipticity = 0.9) presents a light collecting capacity that is 50% greater than that of the standard waveguide coupling configuration and could be further improved by increasing the ellipticity. Moreover, since the dimensions of the spheres are much smaller than those of the ellipses, surface planarization is not required. On the contrary, we show that the absence of a planarization step strongly damages the microsphere lasing performance in the standard configuration.

  3. Inkjet printed ferrite-filled rectangular waveguide X-band isolator

    KAUST Repository

    Farooqui, Muhammad Fahad

    2014-06-01

    For the first time, a rectangular waveguide (RWG) isolator realized through inkjet printing on a ferrite substrate is presented. Yttrium iron garnet (YIG) substrate is used for the realization of the ferrite-filled isolator. Contrary to the substrate integrated waveguide (SIW) approach, all four walls of the waveguide have been inkjet printed on the YIG substrate demonstrating the utility of inkjet printing process for realizing non-planar microwave components. The isolation is achieved by applying an anti-symmetrical DC magnetic bias to the ferrite-filled waveguide which then exhibits a unidirectional mode of operation. The isolator is fed by a microstrip to RWG transition and demonstrates an isolation figure-of-merit (IFM) of more than 51 dB in the operating band from 9.95 GHz to 11.73 GHz with a very high peak IFM of 69 dB. The minimum insertion loss in the operating band is 2.73 dB (including losses from the transitions). The isolator measures 33 mm × 8 mm × 0.4 mm. This work introduces an inkjet printed non-planar microwave device which is easy to fabricate showing the ability of inkjet printing for fabricating complex microwave systems. © 2014 IEEE.

  4. Attenuation in Superconducting Circular Waveguides

    Directory of Open Access Journals (Sweden)

    K. H. Yeap

    2016-09-01

    Full Text Available We present an analysis on wave propagation in superconducting circular waveguides. In order to account for the presence of quasiparticles in the intragap states of a superconductor, we employ the characteristic equation derived from the extended Mattis-Bardeen theory to compute the values of the complex conductivity. To calculate the attenuation in a circular waveguide, the tangential fields at the boundary of the wall are first matched with the electrical properties (which includes the complex conductivity of the wall material. The matching of fields with the electrical properties results in a set of transcendental equations which is able to accurately describe the propagation constant of the fields. Our results show that although the attenuation in the superconducting waveguide above cutoff (but below the gap frequency is finite, it is considerably lower than that in a normal waveguide. Above the gap frequency, however, the attenuation in the superconducting waveguide increases sharply. The attenuation eventually surpasses that in a normal waveguide. As frequency increases above the gap frequency, Cooper pairs break into quasiparticles. Hence, we attribute the sharp rise in attenuation to the increase in random collision of the quasiparticles with the lattice structure.

  5. Micellization and Dynamics of a Block Copolymer

    DEFF Research Database (Denmark)

    Hvidt, Søren

    2006-01-01

    Triblock copolymers of the type EPE, where E and P denote ethylene oxide and propylene oxide blocks, respectively, are industrially important copolymers often called Pluronics or Poloxamers. EPE copolymers form micelles with a core of P blocks and different micellar shapes depending on block leng...

  6. Micellization and Dynamics of a Block Copolymer

    DEFF Research Database (Denmark)

    Hvidt, Søren

    2006-01-01

    Triblock copolymers of the type EPE, where E and P denote ethylene oxide and propylene oxide blocks, respectively, are industrially important copolymers often called Pluronics or Poloxamers. EPE copolymers form micelles with a core of P blocks and different micellar shapes depending on block length...

  7. Prediction for RNA planar pseudoknots

    Institute of Scientific and Technical Information of China (English)

    Li Hengwu; Zhu Daming; Liu Zhendong; Li Hong

    2007-01-01

    Based on m-stems and semi-extensible structure, a model is presented to represent RNA planar pseudoknots, and corresponding dynamic programming algorithm is designed and implemented to predict arbitrary planar pseudoknots and simple non-planar pseudoknots with O(n4) time and O(n3) space. The algorithm folds total 245 sequences in the Pseudobase database, and the test results indicate that the algorithm has good accuracy, sensitivity and specificity.

  8. Copolymers For Capillary Gel Electrophoresis

    Science.gov (United States)

    Liu, Changsheng; Li, Qingbo

    2005-08-09

    This invention relates to an electrophoresis separation medium having a gel matrix of at least one random, linear copolymer comprising a primary comonomer and at least one secondary comonomer, wherein the comonomers are randomly distributed along the copolymer chain. The primary comonomer is an acrylamide or an acrylamide derivative that provides the primary physical, chemical, and sieving properties of the gel matrix. The at least one secondary comonomer imparts an inherent physical, chemical, or sieving property to the copolymer chain. The primary and secondary comonomers are present in a ratio sufficient to induce desired properties that optimize electrophoresis performance. The invention also relates to a method of separating a mixture of biological molecules using this gel matrix, a method of preparing the novel electrophoresis separation medium, and a capillary tube filled with the electrophoresis separation medium.

  9. Planar Para Algebras, Reflection Positivity

    Science.gov (United States)

    Jaffe, Arthur; Liu, Zhengwei

    2017-05-01

    We define a planar para algebra, which arises naturally from combining planar algebras with the idea of ZN para symmetry in physics. A subfactor planar para algebra is a Hilbert space representation of planar tangles with parafermionic defects that are invariant under para isotopy. For each ZN, we construct a family of subfactor planar para algebras that play the role of Temperley-Lieb-Jones planar algebras. The first example in this family is the parafermion planar para algebra (PAPPA). Based on this example, we introduce parafermion Pauli matrices, quaternion relations, and braided relations for parafermion algebras, which one can use in the study of quantum information. An important ingredient in planar para algebra theory is the string Fourier transform (SFT), which we use on the matrix algebra generated by the Pauli matrices. Two different reflections play an important role in the theory of planar para algebras. One is the adjoint operator; the other is the modular conjugation in Tomita-Takesaki theory. We use the latter one to define the double algebra and to introduce reflection positivity. We give a new and geometric proof of reflection positivity by relating the two reflections through the string Fourier transform.

  10. Interrogating Planar Cyclooctatetraenes

    DEFF Research Database (Denmark)

    Hensel, Thomas

    The present thesis addresses the synthesis, analysis and possible applications of different diazadioxa- and azatioxa[8]circulenes to investigate antiaromaticity of a planar cyclooctatetraene (COT). To achieve this goal, different synthetic strategies were developed, all employing 3,6-dihydroxycar......The present thesis addresses the synthesis, analysis and possible applications of different diazadioxa- and azatioxa[8]circulenes to investigate antiaromaticity of a planar cyclooctatetraene (COT). To achieve this goal, different synthetic strategies were developed, all employing 3...... bound carbazole, giving the trimer a helical structure. On the basis of the investigations on oxidative dimerizations of 3,6-dihydroxycarbazoles and previous mechanistic studies by Erdman and Högberg on 1,4-benzqoquinone condensations, the mechanisms of the formation of azatrioxa- and diazadioxa-[8...... (antiaromatic) ring-current influence on the chemical shift values was visible. In addition to that, a comparison of bond-lengths derived from single crystal X-ray structure showed slight alternations (1.40-1.43 Å) in the COTs of azatrioxa- and diazadioxa[8]circulenes. All investigated COT cores therefore...

  11. Polyethylene-Based Tadpole Copolymers

    KAUST Repository

    Alkayal, Nazeeha

    2017-02-15

    Novel well-defined polyethylene-based tadpole copolymers ((c-PE)-b-PS, PE: polyethylene, PS: polystyrene) with ring PE head and linear PS tail are synthesized by combining polyhomologation, atom transfer radical polymerization (ATRP), and Glaser coupling reaction. The -OH groups of the 3-miktoarm star copolymers (PE-OH)-b-PS, synthesized by polyhomologation and ATRP, are transformed to alkyne groups by esterification with propiolic acid, followed by Glaser cyclization and removal of the unreacted linear with Merrifield\\'s resin-azide. The characterization results of intermediates and final products by high-temperature size exclusion chromatography, H NMR spectroscopy, and differential scanning calorimetry confirm the tadpole topology.

  12. Integration of a waveguide self-electrooptic effect device and a vertically coupled interconnect waveguide

    Science.gov (United States)

    Vawter, G. Allen

    2008-02-26

    A self-electrooptic effect device ("SEED") is integrated with waveguide interconnects through the use of vertical directional couplers. Light initially propagating in the interconnect waveguide is vertically coupled to the active waveguide layer of the SEED and, if the SEED is in the transparent state, the light is coupled back to the interconnect waveguide.

  13. Planar solar concentrator featuring alignment-free total-internal-reflection collectors and an innovative compound tracker.

    Science.gov (United States)

    Teng, Tun-Chien; Lai, Wei-Che

    2014-12-15

    This study proposed a planar solar concentrator featuring alignment-free total-internal-reflection (TIR) collectors and an innovative compound tracker. The compound tracker, combining a mechanical single-axis tracker and scrollable prism sheets, can achieve a performance on a par with dual-axis tracking while reducing the cost of the tracking system and increasing its robustness. The alignment-free TIR collectors are assembled on the waveguide without requiring alignment, so the planar concentrator is relatively easily manufactured and markedly increases the feasibility for use in large concentrators. Further, the identical TIR collector is applicable to various-sized waveguide slab without requiring modification, which facilitates flexibility regarding the size of the waveguide slab. In the simulation model, the thickness of the slab was 2 mm, and its maximal length reached 6 m. With an average angular tolerance of ±0.6°, and after considering both the Fresnel loss and the angular spread of the sun, the simulation indicates that the waveguide concentrator of a 1000-mm length provides the optical efficiencies of 62-77% at the irradiance concentrations of 387-688, and the one of a 2000-mm length provides the optical efficiencies of 52-64.5% at the irradiance concentrations of 645-1148. Alternatively, if a 100-mm horizontally staggered waveguide slab is collocated with the alignment-free TIR collectors, the optical efficiency would be greatly improved up to 91.5% at an irradiance concentration of 1098 (C(geo) = 1200X).

  14. Miniaturized Waveguide Fourier Transform Spectrometer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — To characterize the IR optical properties of the metal-coated hollow waveguide ensemble; configure the Hollow Waveguide FTS (HWFTS) chip in such a way that we...

  15. Writing Waveguide in LN With fs Laser

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    We investigated the waveguide formation in Lithium Niobate with Femtosecond laser pulse writing directly. The output optical field through waveguide has been observed and refractive-index change was characterized by using grating method.

  16. Study and simulation for the sharp-corner of silicon-on-insulator waveguides

    Science.gov (United States)

    Sun, De-Gui; Li, Xiaoqi; Wong, Dongxia; Hall, Trevor

    2008-04-01

    The semiconductor industry appears to be encouraging the photonic industry to make highly integrated low-cost optical systems. Planar lightwave circuit (PLC) technology is widely accepted for manufacturing photonic components and Silicon-on-insulator (SOI) waveguides have attracted much research for implementing the highly integrated PLC-based devices. In this work, starting with the guided-mode conversion process and the principle of transportation waves, we mathematically model the structure of corner mirrors of SOI waveguides with a model of effective reflecting interface (ERI). Then we simulate the transfer efficiencies with FDTD method and testify the simulation results with commercial FDTD software tool. Further, we analyze the simulation results and conclude that the conversion efficiency of a corner mirror is determined by several parameters including the geometrical structure, the index-difference of waveguide-reflector materials and the roughness of waveguide-reflector interface. For the corner structure from 90-120°, the optimal transfer efficiency can be achieved more than 98% and the access loss is less than 0.1 dB if the scattering loss of waveguide is not taken into account, but they become 95% and 0.2 dB if the scattering loss is taken into account. For some important PLC components, the deflection angle of 90-120° is good enough for implementing the compact design of highly integrated PLC-based devices.

  17. Loop coupled resonator optical waveguides.

    Science.gov (United States)

    Song, Junfeng; Luo, Lian-Wee; Luo, Xianshu; Zhou, Haifeng; Tu, Xiaoguang; Jia, Lianxi; Fang, Qing; Lo, Guo-Qiang

    2014-10-06

    We propose a novel coupled resonator optical waveguide (CROW) structure that is made up of a waveguide loop. We theoretically investigate the forbidden band and conduction band conditions in an infinite periodic lattice. We also discuss the reflection- and transmission- spectra, group delay in finite periodic structures. Light has a larger group delay at the band edge in a periodic structure. The flat band pass filter and flat-top group delay can be realized in a non-periodic structure. Scattering matrix method is used to calculate the effects of waveguide loss on the optical characteristics of these structures. We also introduce a tunable coupling loop waveguide to compensate for the fabrication variations since the coupling coefficient of the directional coupler in the loop waveguide is a critical factor in determining the characteristics of a loop CROW. The loop CROW structure is suitable for a wide range of applications such as band pass filters, high Q microcavity, and optical buffers and so on.

  18. Wavelength tunable long period gratings based on silica waveguide geometric modulation

    Science.gov (United States)

    Jiang, Jia; Callender, Claire L.; Ledderhof, Christopher J.; Ding, Jianfu

    2011-03-01

    This paper presents planar long period grating (LPG) devices based on a periodic thickness variation in the waveguide core, fabricated by etching into the lower cladding layer prior to definition of the waveguide layer. This periodic geometric change results in a stable grating structure and a permanent refractive index modulation of 10-4 or higher, which is comparable to the index modulation in Ge-doped silica material induced by photo irradiation techniques widely used in fiber grating fabrication. This grating produces a strong resonance at a particular wavelength in the transmission spectrum, enabling a range of applications from wavelength filtering to signal distribution in communication networks. In this work, a polymer and silica hybrid architecture has been implemented in order to achieve wavelength tunability. Using a thermally oxidized silicon layer as a lower cladding, a Ge-doped silica ridge is patterned using conventional photolithography and reactive ion etching to form the waveguide core, which is then covered with a low index fluorinated polymer cladding. While the silica waveguides offer a lower propagation loss and an easy processability, the top polymer allows the device to be thermally tuned over a wide wavelength range by exploiting the opposite thermo-optic coefficient between fluorinated polymer and silica, and the high sensitivity of the underlying LPG to the refractive index of the cladding layer. Strong rejection bands have been demonstrated in the C+L band, in good agreement with theoretical calculations. Corrugated structures have been defined across an extended area under multiple waveguides resulting in coupling of light from the fundamental mode into cladding modes and back into the neighboring waveguides located far from the evanescent coupling distance. This kind of coupler can facilitate devices that require extraction and control of a particular waveguide mode for applications such as multiple channel signal distribution and

  19. Electro-optical circuit board with single-mode glass waveguide optical interconnects

    Science.gov (United States)

    Brusberg, Lars; Neitz, Marcel; Pernthaler, Dominik; Weber, Daniel; Sirbu, Bogdan; Herbst, Christian; Frey, Christopher; Queisser, Marco; Wöhrmann, Markus; Manessis, Dionysios; Schild, Beatrice; Oppermann, Hermann; Eichhammer, Yann; Schröder, Henning; Hâkansson, Andreas; Tekin, Tolga

    2016-03-01

    A glass optical waveguide process has been developed for fabrication of electro-optical circuit boards (EOCB). Very thin glass panels with planar integrated single-mode waveguides can be embedded as a core layer in printed circuit boards for high-speed board-level chip-to-chip and board-to-board optical interconnects over an optical backplane. Such singlemode EOCBs will be needed in upcoming high performance computers and data storage network environments in case single-mode operating silicon photonic ICs generate high-bandwidth signals [1]. The paper will describe some project results of the ongoing PhoxTroT project, in which a development of glass based single-mode on-board and board-to-board interconnection platform is successfully in progress. The optical design comprises a 500 μm thin glass panel (Schott D263Teco) with purely optical layers for single-mode glass waveguides. The board size is accommodated to the mask size limitations of the fabrication (200 mm wafer level process, being later transferred also to larger panel size). Our concept consists of directly assembling of silicon photonic ICs on cut-out areas in glass-based optical waveguide panels. A part of the electrical wiring is patterned by thin film technology directly on the glass wafer surface. A coupling element will be assembled on bottom side of the glass-based waveguide panel for 3D coupling between board-level glass waveguides and chip-level silicon waveguides. The laminate has a defined window for direct glass access for assembling of the photonic integrated circuit chip and optical coupling element. The paper describes the design, fabrication and characterization of glass-based electro-optical circuit board with format of (228 x 305) mm2.

  20. Improved Dynamic Planar Point Location

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Arge, Lars; Georgiadis, Loukas

    2006-01-01

    We develop the first linear-space data structures for dynamic planar point location in general subdivisions that achieve logarithmic query time and poly-logarithmic update time.......We develop the first linear-space data structures for dynamic planar point location in general subdivisions that achieve logarithmic query time and poly-logarithmic update time....

  1. Planar Para Algebras, Reflection Positivity

    CERN Document Server

    Jaffe, Arthur

    2016-01-01

    We define the notion of a planar para algebra, which arises naturally from combining planar algebras with the idea of $\\Z_{N}$ para symmetry in physics. A subfactor planar para algebra is a Hilbert space representation of planar tangles with parafermionic defects, that are invariant under isotopy. For each $\\Z_{N}$, we construct a family of subfactor planar para algebras which play the role of Temperley-Lieb-Jones planar algebras. The first example in this family is the parafermion planar para algebra. Based on this example, we introduce parafermion Pauli matrices, quaternion relations, and braided relations for parafermion algebras which one can use in the study of quantum information. Two different reflections play an important role in the theory of planar para algebras. One is the adjoint operator; the other is the modular conjugation in Tomita-Takesaki theory. We use the latter one to define the double algebra and to introduce reflection positivity. We give a new and geometric proof of reflection positivi...

  2. Planar elliptic growth

    Energy Technology Data Exchange (ETDEWEB)

    Mineev, Mark [Los Alamos National Laboratory

    2008-01-01

    The planar elliptic extension of the Laplacian growth is, after a proper parametrization, given in a form of a solution to the equation for areapreserving diffeomorphisms. The infinite set of conservation laws associated with such elliptic growth is interpreted in terms of potential theory, and the relations between two major forms of the elliptic growth are analyzed. The constants of integration for closed form solutions are identified as the singularities of the Schwarz function, which are located both inside and outside the moving contour. Well-posedness of the recovery of the elliptic operator governing the process from the continuum of interfaces parametrized by time is addressed and two examples of exact solutions of elliptic growth are presented.

  3. Dynamic Planar Convex Hull

    DEFF Research Database (Denmark)

    Jacob, Riko

    We determine the computational complexity of the dynamic convex hull problem in the planar case. We present a data structure that maintains a finite set of n points in the plane under insertion and deletion of points in amortized O(log n) time per operation. The space usage of the data structure...... is O(n). The data structure supports extreme point queries in a given direction, tangent queries through a given point, and queries for the neighboring points on the convex hull in O(log n) time. The extreme point queries can be used to decide whether or not a given line intersects the convex hull......, and the tangent queries to determine whether a given point is inside the convex hull. The space usage of the data structure is O(n). We give a lower bound on the amortized asymptotic time complexity that matches the performance of this data structure....

  4. Dynamic Planar Convex Hull

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølfting; Jacob, Rico

    2002-01-01

    In this paper we determine the computational complexity of the dynamic convex hull problem in the planar case. We present a data structure that maintains a finite set of n points in the plane under insertion and deletion of points in amortized O(log n) time per operation. The space usage...... of the data structure is O(n). The data structure supports extreme point queries in a given direction, tangent queries through a given point, and queries for the neighboring points on the convex hull in O(log n) time. The extreme point queries can be used to decide whether or not a given line intersects...... the convex hull, and the tangent queries to determine whether a given point is inside the convex hull. We give a lower bound on the amortized asymptotic time complexity that matches the performance of this data structure....

  5. Ferromagnetic Planar Nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Carbucicchio, M.; Rateo, M. [University of Parma, and INFM, Department of Physics (Italy)

    2004-12-15

    Modern permanent magnets require a high coercive field on account of a strong magnetocrystalline anisotropy, as well as a high saturation magnetization and high Curie temperature. The achievement of so different characteristics in a unique phase is the present main difficulty. In principle, this problem can be solved combining the high saturation magnetization of a soft phase with the high magnetic anisotropy of a hard phase, via the exchange coupling on a nanometric scale. The first attempts showed the feasibility of planar magnetic nanocomposites, where soft and hard magnetic layers are intercalated, but on the other hand they also stressed the difficulties still existing. The present paper reviews some theoretical aspects and experimental results, pointing out the potentiality of Moessbauer spectroscopy in determining the spin configuration, as well as the nature and thickness of interfaces, which strongly influence the exchange interaction in these systems.

  6. Buried ion-exchanged glass waveguides: burial-depth dependence on waveguide width.

    Science.gov (United States)

    Madasamy, P; West, B R; Morrell, M M; Geraghty, D F; Honkanen, S; Peyghambarian, N

    2003-07-01

    A detailed theoretical and experimental study of the depth dependence of buried ion-exchanged waveguides on waveguide width is reported. Modeling, which includes the effect of nonhomogeneous time-dependent electric field distribution, agrees well with our experiments showing that burial depth increases linearly with waveguide width. These results may be used in the proper design of integrated optical circuits that need waveguides of different widths at different sections, such as arrayed waveguide gratings.

  7. Polyether-polyester graft copolymer

    Science.gov (United States)

    Bell, Vernon L. (Inventor)

    1987-01-01

    Described is a polyether graft polymer having improved solvent resistance and crystalline thermally reversible crosslinks. The copolymer is prepared by a novel process of anionic copolymerization. These polymers exhibit good solvent resistance and are well suited for aircraft parts. Previous aromatic polyethers, also known as polyphenylene oxides, have certain deficiencies which detract from their usefulness. These commercial polymers are often soluble in common solvents including the halocarbon and aromatic hydrocarbon types of paint thinners and removers. This limitation prevents the use of these polyethers in structural articles requiring frequent painting. In addition, the most popular commercially available polyether is a very high melting plastic. This makes it considerably more difficult to fabricate finished parts from this material. These problems are solved by providing an aromatic polyether graft copolymer with improved solvent resistance and crystalline thermally reversible crosslinks. The graft copolymer is formed by converting the carboxyl groups of a carboxylated polyphenylene oxide polymer to ionic carbonyl groups in a suitable solvent, reacting pivalolactone with the dissolved polymer, and adding acid to the solution to produce the graft copolymer.

  8. Liquid ethylene-propylene copolymers

    Science.gov (United States)

    Rhein, R. A.; Ingham, J. D.; Humphrey, M. F.

    1975-01-01

    Oligomers are prepared by heating solid ethylene-propylene rubber in container that retains solid and permits liquid product to flow out as it is formed. Molecular weight and viscosity of liquids can be predetermined by process temperature. Copolymers have low viscosity for given molecular weight.

  9. Characterization of Annealed, Proton Exchange Optical Waveguides in Y-cut MgO∶LiNbO3 Crystal

    Institute of Scientific and Technical Information of China (English)

    CAO Xia; XIA Yuxing; YANG Yi; WANG Pinghe; CHEN Xianfeng

    2000-01-01

    It is reported the results of a systematic study on planar waveguides fabricated in Y-cut MgO∶LiNbO3 crystal. The index profile of the as-exchanged waveguide can be modeled as a step-like one. It is deduced the diffusion coefficient and the activation energy for the proton exchange process. The surface index increases Δne of around 0.127 after proton exchange can be reduced by post thermal annealing. The effects of the annealing on the index profile and guide depth were found not as fast as it does on a pure LiNbO3 crystal.

  10. Plasmonic waveguides cladded by hyperbolic metamaterials

    DEFF Research Database (Denmark)

    Ishii, Satoshi; Shalaginov, Mikhail Y.; Babicheva, Viktoriia E.

    2014-01-01

    Strongly anisotropic media with hyperbolic dispersion can be used for claddings of plasmonic waveguides (PWs). In order to analyze the fundamental properties of such waveguides, we analytically study 1D waveguides arranged from a hyperbolic metamaterial (HMM) in a HMM-Insulator-HMM (HIH) structure...

  11. A Planarity Criterion for Graphs

    CERN Document Server

    Dosen, Kosta

    2012-01-01

    It is proven that a connected graph is planar if and only if all its cocycles with at least four edges are "grounded" in the graph. The notion of grounding of this planarity criterion, which is purely combinatorial, stems from the intuitive idea that with planarity there should be a linear ordering of the edges of a cocycle such that in the two subgraphs remaining after the removal of these edges there can be no crossing of disjoint paths that join the vertices of these edges. The proof given in the paper of the right-to-left direction of the equivalence is based on Kuratowski's Theorem for planarity involving $K_{3,3}$ and $K_5$, but the criterion itself does not mention $K_{3,3}$ and $K_5$. Some other variants of the criterion are also shown necessary and sufficient for planarity.

  12. Graphene nano-ribbon waveguides

    CERN Document Server

    He, S; He, Y

    2013-01-01

    Graphene as a one-atom-thick platform for infrared metamaterial plays an important role in optical science and engineering. Here we study the unique properties of some plasmonic waveguides based on graphene nano-ribbon. It is found that a graphene ribbon of finite width leads to the occurrence of coupled edge mode. The single-mode region of a single freestanding graphene ribbon is identified at a fixed frequency of 30 THz. A low-loss waveguide structure, consisting of a graphene layer, a silica buffer layer and silicon substrate is proposed to reduce the propagation loss and obtain a high figure of merit for future integration of waveguide devices. Furthermore, two coupled ribbon configurations, namely, side-side coupling and top-bottom coupling, are investigated. As a device example, a nano-ring cavity of ultra-small size is designed.

  13. Influence of solvent on micellar morphologies of semifluorinated block copolymers.

    Science.gov (United States)

    Lee, Min Young; Kim, Sang Jae; Jeong, Yeon Tae; Kim, Joo Hyun; Gal, Yeong-Soon; Lim, Kwon Taek

    2009-12-01

    The influence of solvents on micellar architectures of block copolymers composed of poly(1H,1H-dihydroperfluorooctyl methacrylate) and poly(ethylene oxide) was investigated. In this study, binary solvents with desired proportions were chosen, which had remarkable influence on the morphology of the resulting micelles. With simple adjusting the composition of the binary solvent of chloroform and trichlorofluoromethane, interesting shapes of micelle-like aggregates, such as core-shell, cylinder, worm-like and inverted micelles were formed with sizes of 15, 70, 30 and 250 nm, respectively. In the case of methanol/water system, core-shell spheres and vesicles were produced by varying the proportion of the contents. The morphologies were also tuned to honeycomb-like and bowl-shaped micelles as well as large planar lamellae with holes in DMF and water binary solvent.

  14. A Novel SIW-Based Planar W-Band GaAs Gunn Harmonic Oscillator

    Science.gov (United States)

    Liu, Yong; Tang, Xiao-Hong; Cao, Zhou

    2010-10-01

    Based on the substrate integrated waveguide (SIW) technology, a novel W-band low phase noise GaAs Gunn planar harmonic oscillator is developed in this paper. The technique of harmonic extraction from Gunn diodes and SIW resonant cavity structures are discussed in detail. Due to the high quality factor and planar structure of the SIW cavity resonator, the oscillator is characterized by some advantages such as low phase noise, small size, low cost and planar integration. The measured phase noise is -108.56 dBc/Hz at 1 MHz offset and the output power is more than 9 dBm at 94.78 GHz. A 300 MHz of linear tuning range with power fluctuation less than 1.5 dB is observed when the Gunn diode is biased from 4 to 5.3 V.

  15. Analysis of a Finite Array of Open-Ended Waveguides Based on a Multimode Equivalent Network Including the Effects of Finite Matching Layers and Groundplane

    NARCIS (Netherlands)

    Bolt, R.; Bertuch, T.; Gerini, G.; Neto, A.

    2004-01-01

    In this contribution we present a highfrequency model to describe the reflections of surface waves at the edges of a truncated and grounded dielectric stratification. This model can eventually be integrated with an existing model that is able to analyse realistic finite open-ended planar waveguide

  16. TSUNAMI WAVE PROPAGATION ALONG WAVEGUIDES

    Directory of Open Access Journals (Sweden)

    Andrei G. Marchuk

    2009-01-01

    Full Text Available This is a study of tsunami wave propagation along the waveguide on a bottom ridge with flat sloping sides, using the wave rays method. During propagation along such waveguide the single tsunami wave transforms into a wave train. The expression for the guiding velocities of the fastest and slowest signals is defined. The tsunami wave behavior above the ocean bottom ridges, which have various model profiles, is investigated numerically with the help of finite difference method. Results of numerical experiments show that the highest waves are detected above a ridge with flat sloping sides. Examples of tsunami propagation along bottom ridges of the Pacific Ocean are presented.

  17. Impacts of Repeat Unit Structure and Copolymer Architecture on Thermal and Solution Properties in Homopolymers, Copolymers, and Copolymer Blends

    Science.gov (United States)

    Marrou, Stephen Raye

    Gradient copolymers are a relatively new type of copolymer architecture in which the distribution of comonomers gradually varies over the length of the copolymer chain, resulting in a number of unusual properties derived from the arrangement of repeat units. For example, nanophase-segregated gradient copolymers exhibit extremely broad glass transition temperatures (Tgs) resulting from the wide range of compositions present in the nanostructure. This dissertation presents a number of studies on how repeat unit structure and copolymer architecture dictate bulk and solution properties, specifically taking inspiration from the gradient copolymer architecture and comparing the response from this compositionally heterogeneous material to other more conventional materials. The glass transition behavior of a range of common homopolymers was studied to determine the effects of subunit structure on Tg breadth, observing a significant increase in T g breadth with increasing side chain length in methacrylate-based homopolymers and random copolymers. Additionally, increasing the composition distribution of copolymers, either by blending individual random copolymers of different overall composition or synthesizing random copolymers to high conversion, resulted in significant increases to Tg breadth. Plasticization of homopolymers and random copolymers with low molecular weight additives also served to increase the Tg breadth; the most dramatic effect was observed in the selective plasticization of a styrene/4-vinylpyridine gradient copolymer with increases in T g breadth to values above 100 °C. In addition, the effects of repeat unit structure and copolymer architecture on other polymer properties besides Tg were also investigated. The intrinsic fluorescence of styrene units in styrene-containing copolymers was studied, noting the impact of repeat unit structure and copolymer architecture on the resulting fluorescence spectra in solution. The impact of repeat unit structure on

  18. Two-Dimentional Photonic Crystal Waveguides

    DEFF Research Database (Denmark)

    Søndergaard, Thomas; Dridi, Kim

    1999-01-01

    possible a novel class of optical microcavities, whereas line defects make possible a novel class of waveguides. In this paper we will analyze two-dimensional photonic crystal waveguides based on photonic crystals with rods arranged on a triangular and a square lattice using a plane-wave expansion method...... and a finite-difference-time-domain (FDTD) method. Design parameters, i.e. dielectric constants, rod diameter and waveguide width, where these waveguides are single-moded and multi-moded will be given. We will also show our recent results regarding the energy-flow (the Poynting vector) in these waveguides...

  19. Quantum Electrodynamics in Photonic Crystal Waveguides

    DEFF Research Database (Denmark)

    Nielsen, Henri Thyrrestrup

    In this thesis we have performed quantum electrodynamics (QED) experiments in photonic crystal (PhC) waveguides and cavity QED in the Anderson localized regime in disordered PhC waveguides. Decay rate measurements of quantum dots embedded in PhC waveguides has been used to map out the variations...... probability. The Q-factor distributions of Anderson localized modes have been measured in PhC waveguides with articial induced disorder with embedded emitters. The largest Q-factors are found in the sample with the smallest amount of disorder. From a comparison with the waveguide model the localization length...

  20. Plasmonic waveguides with hyperbolic multilayer cladding

    CERN Document Server

    Babicheva, Viktoriia E; Ishii, Satoshi; Boltasseva, Alexandra; Kildishev, Alexander V

    2014-01-01

    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 homogenization, we calculate the resonant eigenmodes of the finite-width cladding layers, and find agreement with the resonant features in the dispersion of the cladded waveguides. We show that at the resonant widths, the propagating modes of the waveguides are coupled to the cladding eigenmodes and hence, are strongly absorbed. By avoiding the resonant widths in the design of the actual waveguides, the strong absorption can be eliminated.

  1. Non-liftoff block copolymer nanolithography of magnetic nanodot arrays

    Science.gov (United States)

    Baruth, A.; Rodwogin, M. D.; Shankar, A.; Torija, M. A.; Erickson, M. J.; Hillmyer, M. A.; Leighton, C.

    2011-03-01

    Nanolithographic techniques based on self-assembled block copolymer templates offer exceptional potential for fabrication of large-area nanostructure arrays from a wide variety of functional materials. Despite significant progress with control of the template ordering, and development of pattern transfer schemes, significant issues exist with common techniques such as lift-off and etching. Here, we demonstrate successful execution of a nanolithographic process based on climate-controlled solvent annealing of easily degradable cylinder-forming poly(styrene- b -lactide) block copolymer films that avoids both lift-off and the most challenging aspects of etching. Essentially, we use an overfill/planarize/etch-back ``Damascene-type'' process, exploiting the large Ar ion beam etch rate contrast between polystyrene and typical metals. The process is demonstrated via formation of a large-area array of 12 nm thick, 25 +/- 3 nm diameter Ni 80 Fe 20 nanodots (~ 0.4 x 1012 dots/ in 2) with hexagonally-close-packed local order. Extensive microscopy, magnetometry, and electrical measurements provide detailed characterization of the pattern formation and fidelity. We argue that this generic approach can be applied to a wide variety of materials and is scalable to even smaller feature sizes. Funded by NSF MRSEC.

  2. Compact on-Chip Temperature Sensors Based on Dielectric-Loaded Plasmonic Waveguide-Ring Resonators

    Directory of Open Access Journals (Sweden)

    Sergey I. Bozhevolnyi

    2011-02-01

    Full Text Available The application of a waveguide-ring resonator based on dielectric-loaded surface plasmon-polariton waveguides as a temperature sensor is demonstrated in this paper and the influence of temperature change to the transmission through the waveguide-ring resonator system is comprehensively analyzed. The results show that the roundtrip phase change in the ring resonator due to the temperature change is the major reason for the transmission variation. The performance of the temperature sensor is also discussed and it is shown that for a waveguide-ring resonator with the resonator radius around 5 mm and waveguide-ring gap of 500 nm which gives a footprint around 140 µm2, the temperature sensitivity at the order of 10−2 K can be achieved with the input power of 100 mW within the measurement sensitivity limit of a practical optical detector.

  3. Optical Slot-Waveguide Based Biochemical Sensors

    Directory of Open Access Journals (Sweden)

    Carlos Angulo Barrios

    2009-06-01

    Full Text Available Slot-waveguides allow light to be guided and strongly confined inside a nanometer-scale region of low refractive index. Thus stronger light-analyte interaction can be obtained as compared to that achievable by a conventional waveguide, in which the propagating beam is confined to the high-refractive-index core of the waveguide. In addition, slot-waveguides can be fabricated by employing CMOS compatible materials and technology, enabling miniaturization, integration with electronic, photonic and fluidic components in a chip, and mass production. These advantages have made the use of slot-waveguides for highly sensitive biochemical optical integrated sensors an emerging field. In this paper, recent achievements in slot-waveguide based biochemical sensing will be reviewed. These include slot-waveguide ring resonator based refractometric label-free biosensors, label-based optical sensing, and nano-opto-mechanical sensors.

  4. Closed planar curves without inflections

    CERN Document Server

    Ohno, Shuntaro; Umehara, Masaaki

    2011-01-01

    We define a computable topological invariant $\\mu(\\gamma)$ for generic closed planar regular curves $\\gamma$, which gives an effective lower bound for the number of inflection points on a given generic closed planar curve. Using it, we classify the topological types of locally convex curves (i.e. closed planar regular curves without inflections) whose numbers of crossings are less than or equal to five. Moreover, we discuss the relationship between the number of double tangents and the invariant $\\mu(\\gamma)$ on a given $\\gamma$.

  5. Volatile organic compound detection using nanostructured copolymers.

    Science.gov (United States)

    Li, Bo; Sauvé, Genevieve; Iovu, Mihaela C; Jeffries-El, Malika; Zhang, Rui; Cooper, Jessica; Santhanam, Suresh; Schultz, Lawrence; Revelli, Joseph C; Kusne, Aaron G; Kowalewski, Tomasz; Snyder, Jay L; Weiss, Lee E; Fedder, Gary K; McCullough, Richard D; Lambeth, David N

    2006-08-01

    Regioregular polythiophene-based conductive copolymers with highly crystalline nanostructures are shown to hold considerable promise as the active layer in volatile organic compound (VOC) chemresistor sensors. While the regioregular polythiophene polymer chain provides a charge conduction path, its chemical sensing selectivity and sensitivity can be altered either by incorporating a second polymer to form a block copolymer or by making a random copolymer of polythiophene with different alkyl side chains. The copolymers were exposed to a variety of VOC vapors, and the electrical conductivity of these copolymers increased or decreased depending upon the polymer composition and the specific analytes. Measurements were made at room temperature, and the responses were found to be fast and appeared to be completely reversible. Using various copolymers of polythiophene in a sensor array can provide much better discrimination to various analytes than existing solid state sensors. Our data strongly indicate that several sensing mechanisms are at play simultaneously, and we briefly discuss some of them.

  6. Bioinspired catecholic copolymers for antifouling surface coatings.

    Science.gov (United States)

    Cho, Joon Hee; Shanmuganathan, Kadhiravan; Ellison, Christopher J

    2013-05-01

    We report here a synthetic approach to prepare poly(methyl methacrylate)-polydopamine diblock (PMMA-PDA) and triblock (PDA-PMMA-PDA) copolymers combining mussel-inspired catecholic oxidative chemistry and atom transfer radical polymerization (ATRP). These copolymers display very good solubility in a range of organic solvents and also a broad band photo absorbance that increases with increasing PDA content in the copolymer. Spin-cast thin films of the copolymer were stable in water and showed a sharp reduction (by up to 50%) in protein adsorption compared to those of neat PMMA. Also the peak decomposition temperature of the copolymers was up to 43°C higher than neat PMMA. The enhanced solvent processability, thermal stability and low protein adsorption characteristics of this copolymer makes it attractive for variety of applications including antifouling coatings on large surfaces such as ship hulls, buoys, and wave energy converters.

  7. Dielectric waveguide amplifiers and lasers

    NARCIS (Netherlands)

    Pollnau, Markus

    The performance of semiconductor amplifiers and lasers has made them the preferred choice for optical gain on a micro-chip. In the past few years, we have demonstrated that also rare-earth-ion-doped dielectric waveguides show remarkable performance, ranging from a small-signal gain per unit length

  8. Photonic-crystal waveguide biosensor

    DEFF Research Database (Denmark)

    Skivesen, Nina; Têtu, Amélie; Kristensen, Martin

    2007-01-01

    A photonic-crystal waveguide sensor is presented for biosensing. The sensor is applied for refractive index measurements and detection of protein-concentrations. Concentrations around 10 μg/ml (0.15μMolar) are measured with excellent signal to noise ratio, and a broad, dynamic refractive index se...

  9. Coupled-resonator optical waveguides

    DEFF Research Database (Denmark)

    Raza, Søren; Grgic, Jure; Pedersen, Jesper Goor

    2010-01-01

    Coupled-resonator optical waveguides hold potential for slow-light propagation of optical pulses. The dispersion properties may adequately be analyzed within the framework of coupled-mode theory. We extend the standard coupled-mode theory for such structures to also include complex-valued paramet...

  10. Parabolic tapers for overmoded waveguides

    Science.gov (United States)

    Doane, J.L.

    1983-11-25

    A waveguide taper with a parabolic profile, in which the distance along the taper axis varies as the square of the tapered dimension, provides less mode conversion than equal length linear tapers and is easier to fabricate than other non-linear tapers.

  11. The influence of chain stretching on the phase behavior of multiblock copolymer and comb copolymer melts

    NARCIS (Netherlands)

    Angerman, HJ; ten Brinke, G

    2003-01-01

    The subject of this paper is inspired by microphase-separated copolymer melts in which a small-scale structure is present inside one of the phases of a large-scale structure. Such a situation can arise in a diblock copolymer melt, if one of the blocks of the diblock is in itself a multiblock copolym

  12. Blends of Styrene-Butadiene-Styrene Triblock Copolymer with Random Styrene-Maleic Anhydride Copolymers

    NARCIS (Netherlands)

    Piccini, Maria Teresa; Ruggeri, Giacomo; Passaglia, Elisa; Picchioni, Francesco; Aglietto, Mauro

    2002-01-01

    Blends of styrene-butadiene-styrene triblock copolymer (SBS) with random styrene-maleic anhydride copolymers (PS-co-MA), having different MA content, were prepared in a Brabender Plastigraph mixer. The presence of polystyrene (PS) blocks in the SBS copolymer and the high styrene content (93 and 86 w

  13. A Directly-Written Monolithic Waveguide-Laser Incorporating a DFB Waveguide-Bragg Grating

    CERN Document Server

    Marshall, Graham D; Ams, Martin; Piper, James A; Withford, Michael J

    2008-01-01

    We report the fabrication and performance of the first C-band directly-written monolithic waveguide-laser. The waveguide-laser device was created in an Erbium and Ytterbium doped phosphate glass host and consisted of an optical waveguide that included a distributed feedback Bragg grating structure. The femtosecond laser direct-write technique was used to create both the waveguide and the waveguide-Bragg grating simultaneously and in a single processing step. The waveguide-laser was optically pumped at approximately 980 nm and lased at 1537nm with a bandwidth of less than 4 pm.

  14. Quadratic Tangles in Planar Algebras

    CERN Document Server

    Jones, Vaughan F R

    2010-01-01

    In planar algebras, we show how to project certain simple "quadratic" tangles onto the linear space spanned by "linear" and "constant" tangles. We obtain some corollaries about the principal graphs and annular structure of subfactors.

  15. Planar immersion lens with metasurfaces

    CERN Document Server

    Ho, John S; Tanabe, Yuji; Yeh, Alexander J; Fan, Shanhui; Poon, Ada S Y

    2015-01-01

    The solid immersion lens is a powerful optical tool that allows light entering material from air or vacuum to focus to a spot much smaller than the free-space wavelength. Conventionally, however, they rely on semispherical topographies and are non-planar and bulky, which limits their integration in many applications. Recently, there has been considerable interest in using planar structures, referred to as metasurfaces, to construct flat optical components for manipulating light in unusual ways. Here, we propose and demonstrate the concept of a planar immersion lens based on metasurfaces. The resulting planar device, when placed near an interface between air and dielectric material, can focus electromagnetic radiation incident from air to a spot in material smaller than the free-space wavelength. As an experimental demonstration, we fabricate an ultrathin and flexible microwave lens and further show that it achieves wireless energy transfer in material mimicking biological tissue.

  16. Planar graphs theory and algorithms

    CERN Document Server

    Nishizeki, T

    1988-01-01

    Collected in this volume are most of the important theorems and algorithms currently known for planar graphs, together with constructive proofs for the theorems. Many of the algorithms are written in Pidgin PASCAL, and are the best-known ones; the complexities are linear or 0(nlogn). The first two chapters provide the foundations of graph theoretic notions and algorithmic techniques. The remaining chapters discuss the topics of planarity testing, embedding, drawing, vertex- or edge-coloring, maximum independence set, subgraph listing, planar separator theorem, Hamiltonian cycles, and single- or multicommodity flows. Suitable for a course on algorithms, graph theory, or planar graphs, the volume will also be useful for computer scientists and graph theorists at the research level. An extensive reference section is included.

  17. Silica reinforced triblock copolymer gels

    DEFF Research Database (Denmark)

    Theunissen, E.; Overbergh, N.; Reynaers, H.

    2004-01-01

    The effect of silica and polymer coated silica particles as reinforcing agents on the structural and mechanical properties of polystyrene-poly(ethylene/butylene)-polystyrene (PS-PEB-PS) triblock gel has been investigated. Different types of chemically modified silica have been compared in order...... a viscoclastic rubber to a plastic fluid and from a plastic fluid to a viscoelastic liquid are shifted to more elevated temperatures when silica is added to the triblock copolymer gel. (C) 2004 Elsevier Ltd. All rights reserved....

  18. Copolymers of fluorinated polydienes and sulfonated polystyrene

    Science.gov (United States)

    Mays, Jimmy W.; Gido, Samuel P.; Huang, Tianzi; Hong, Kunlun

    2009-11-17

    Copolymers of fluorinated polydienes and sulfonated polystyrene and their use in fuel cell membranes, batteries, breathable chemical-biological protective materials, and templates for sol-gel polymerization.

  19. Drinfeld center of planar algebra

    CERN Document Server

    Das, Paramita; Gupta, Ved Prakash

    2012-01-01

    We introduce fusion and contragadient of affine representations of a planar algebra $P$ (not necessarily having finite depth). We prove that if $N \\subset M$ is a subfactor realization of $P$, then the Drinfeld center of the $N$-$N$-bimodule category generated by $_N L^2 (M)_M$, is equivalent to the category Hilbert affine representations of $P$ satisfying certain finiteness criterion. As a consequence, we prove Kevin Walker's conjecture for planar algebras.

  20. Spherical assemblies formed from π-conjugated alternating copolymers having fluorene and thiophene components

    Science.gov (United States)

    Yamamoto, Yohei; Tong, Liang

    2014-03-01

    Self-assembly of conducting polymers were comprehensively studied by means of slow precipitation from polymer solutions upon addition of a vapor of nonsolvents. Polymers such as polyfluorene and polythiophene hardly formed defined and discrete objects but only gave ill-defined aggregates. In contrast, some alternating copolymers having both fluorene and thiophene components in their repeating unit self-assembled into well-shaped spheres with sub-micrometer to several micrometer in the diameters. The differences in the assembling geometries derive from the crystallinity of the polymers, where the copolymers possess large steric hindrance on their backbone that reduces planarity of the polymers and inhibits anisotropic crystal growth. Changing the assembling parameters can systematically control diameter and deviation of the spheres.

  1. Disk-cylinder and disk-sphere nanoparticles via a block copolymer blend solution construction.

    Science.gov (United States)

    Zhu, Jiahua; Zhang, Shiyi; Zhang, Ke; Wang, Xiaojun; Mays, Jimmy W; Wooley, Karen L; Pochan, Darrin J

    2013-01-01

    Researchers strive to produce nanoparticles with complexity in composition and structure. Although traditional spherical, cylindrical and membranous, or planar, nanostructures are ubiquitous, scientists seek more complicated geometries for potential functionality. Here we report the simple solution construction of multigeometry nanoparticles, disk-sphere and disk-cylinder, through a straightforward, molecular-level, blending strategy with binary mixtures of block copolymers. The multigeometry nanoparticles contain disk geometry in the core with either spherical patches along the disk periphery in the case of disk-sphere particles or cylindrical edges and handles in the case of the disk-cylinder particles. The portions of different geometry in the same nanoparticles contain different core block chemistry, thus also defining multicompartments in the nanoparticles. Although the block copolymers chosen for the blends are important for the definition of the final hybrid particles, the control of the kinetic pathway of assembly is critical for successful multigeometry particle construction.

  2. Ion-exchanged glass waveguides with low birefringence for a broad range of waveguide widths.

    Science.gov (United States)

    Yliniemi, Sanna; West, Brian R; Honkanen, Seppo

    2005-06-01

    Optical communications networks require integrated photonic components with negligible polarization dependence, which typically means that the waveguides must feature very low birefringence. Recent studies have shown that waveguides with low birefringence can be obtained, e.g., by use of silica-on-silicon waveguides or buried ion-exchanged glass waveguides. However, many integrated photonic circuits consist of waveguides with varying widths. Therefore low birefringence is consequently required for waveguides having different widths. This is a difficult task for most waveguide fabrication technologies. We present experimental results on waveguide birefringence for buried silver-sodium ion-exchanged glass waveguides. We show that the waveguide birefringence of the order of 10(-6) for waveguide mask opening widths ranging from 2 to 10 microm can be obtained by postprocessing the sample through annealing at an elevated temperature. The measured values are in agreement with the values calculated with our modeling software for ion-exchanged glass waveguides. This unique feature of ion-exchanged waveguides may be of significant importance in a wide variety of integrated photonic circuits requiring polarization-independent operation.

  3. Polymer waveguide based hybrid opto-electric integration technology

    Science.gov (United States)

    Mao, Jinbin; Deng, Lingling; Jiang, Xiyan; Ren, Rong; Zhai, Yumeng; Wang, Jin

    2014-10-01

    While monolithic integration especially based on InP appears to be quite an expensive solution for optical devices, hybrid integration solutions using cheaper material platforms are considered powerful competitors because of the high freedom of design, yield optimization and relative cost-efficiency. Among them, the polymer planar-lightwave circuit (PLC) technology is regarded attractive as polymer offers the potential of fairly simple and low-cost fabrication, and of low-cost packaging. In our work, polymer PLC was fabricated by using the standard reactive ion etching (RIE) technique, while other active and passive devices can be integrated on the polymer PLC platform. Exemplary polymer waveguide devices was a 13-channel arrayed waveguide grating (AWG) chip, where the central channel cross-talk was below -30dB and the polarization dependent frequency shift was mitigated by inserting a half wave plate. An optical 900 hybrid was also realized with one 2×4 multi-mode interferometer (MMI). The excess insertion losses are below 4dB for the C-band, while the transmission imbalance is below 1.2dB. When such an optical hybrid was integrated vertically with mesa-type photodiodes, the responsivity of the individual PD was around 0.06 A/W, while the 3 dB bandwidth reaches 24 ~ 27 GHz, which is sufficient for 100Gbit/s receivers. Another example of the hybrid integration was to couple the polymer waveguides to fiber by applying fiber grooves, whose typical loss value was 0.2 dB per-facet over a broad spectral range from 1200-1600 nm.

  4. First order Bragg grating filters in silicon on insulator waveguides

    Science.gov (United States)

    Waugh, Peter Michael

    2008-08-01

    The subject of this project is the design; analysis, fabrication and characterisation of first order Bragg Grating optical filters in Silicon-on-Insulator (SOI) planar waveguides. It is envisaged that this work will result in the possibility of Bragg Grating filters for use in Silicon Photonics. It is the purpose of the work to create as far as is possible flat surface waveguides so as to facilitate Thermo-Optic tuning and also the incorporation into rib-waveguide Silicon Photonics. The spectral response of the shallow Bragg Gratings was modelled using Coupled Mode Theory (CMT) by way of RSoft Gratingmod TM. Also the effect of having a Bragg Grating with alternate layers of refractive index of 1.5 and 3.5 was simulated in order to verify that Silica and Silicon layered Bragg Gratings could be viable. A series of Bragg Gratings were patterned on 1.5 micron SOI at Philips in Eindhoven, Holland to investigate the variation of grating parameters with a) the period of the gratings b) the mark to space ratio of the gratings and c) the length of the region converted to Bragg Gratings (i.e. the number of grating period repetitions). One set of gratings were thermally oxidised at Philips in Eindhoven and another set were ion implanted with Oxygen ions at the Ion Beam Facility, University of Surrey, England. The gratings were tested and found to give transmission minima at approximately 1540 nanometres and both methods of creating flat surfaces were found to give similar minima. Atomic Force Microscopy was applied to the grating area of the as-implanted samples in the Advanced Technology Institute, University of Surrey, which were found to have surface undulations in the order of 60 nanometres.

  5. Ultra-wideband filtering of spoof surface plasmon polaritons using deep subwavelength planar structures

    Science.gov (United States)

    Hu, Ming Zhe; Zhang, Hao Chi; Yin, Jia Yuan; Ding, Zhao; Liu, Jun Feng; Tang, Wen Xuan; Cui, Tie Jun

    2016-11-01

    Novel ultra-wideband filtering of spoof surface plasmon polaritons (SPPs) is proposed in the microwave frequency using deep subwavelength planar structures printed on thin and flexible dielectric substrate. The proposed planar SPPs waveguide is composed of two mirror-oriented metallic corrugated strips, which are further decorated with parallel-arranged slots in the main corrugated strips. This compound structure provides deep subwavelength field confinement as well as flexible parameters when employed as a plasmonic waveguide, which is potential to construct miniaturization. Using momentum and impedance matching technology, we achieve a smooth conversion between the proposed SPPs waveguide and the conventional transmission line. To verify the validity of the design, we fabricate a spoof SPPs filter, and the measured results illustrate excellent performance, in which the reflection coefficient is less than ‑10 dB within the ‑3 dB passband from 1.21 GHz to 7.21 GHz with the smallest insertion loss of 1.23 dB at 2.21 GHz, having very good agreements with numerical simulations. The ultra-wideband filter with low insertion loss and high transmission efficiency possesses great potential in modern communication systems.

  6. Ultra-wideband filtering of spoof surface plasmon polaritons using deep subwavelength planar structures

    Science.gov (United States)

    Hu, Ming Zhe; Zhang, Hao Chi; Yin, Jia Yuan; Ding, Zhao; Liu, Jun Feng; Tang, Wen Xuan; Cui, Tie Jun

    2016-01-01

    Novel ultra-wideband filtering of spoof surface plasmon polaritons (SPPs) is proposed in the microwave frequency using deep subwavelength planar structures printed on thin and flexible dielectric substrate. The proposed planar SPPs waveguide is composed of two mirror-oriented metallic corrugated strips, which are further decorated with parallel-arranged slots in the main corrugated strips. This compound structure provides deep subwavelength field confinement as well as flexible parameters when employed as a plasmonic waveguide, which is potential to construct miniaturization. Using momentum and impedance matching technology, we achieve a smooth conversion between the proposed SPPs waveguide and the conventional transmission line. To verify the validity of the design, we fabricate a spoof SPPs filter, and the measured results illustrate excellent performance, in which the reflection coefficient is less than −10 dB within the −3 dB passband from 1.21 GHz to 7.21 GHz with the smallest insertion loss of 1.23 dB at 2.21 GHz, having very good agreements with numerical simulations. The ultra-wideband filter with low insertion loss and high transmission efficiency possesses great potential in modern communication systems. PMID:27883028

  7. Electromagnetic Scattering at the Waveguide Step between Equilateral Triangular Waveguides

    Directory of Open Access Journals (Sweden)

    Ana Morán-López

    2016-01-01

    Full Text Available The analysis of the electromagnetic scattering at discontinuities between equilateral triangular waveguides is studied. The complete electromagnetic solution is derived using analytical closed form expressions for the mode spectrum of the equilateral waveguide. The mathematical formulation of the electromagnetic scattering problem is based on the quasi-analytical Mode-Matching method. This method benefits from the electromagnetic field division into symmetries as well as from the plane wave formulation presented for the expressions involved. The unification of the surface integrals used in the method thanks to the plane wave formulation is revealed, leading to expressions that are very well suited for its implementation in an electromagnetic analysis and design code. The obtained results for some cases of interest (building blocks for microwave components for communication systems are verified using other numerical methods included in a commercial software package, showing the potential of the presented approach based on quasi-analytic expressions.

  8. Waveguide structure optimization of arrayed waveguide gratings concatenation in cascaded optical add/drop multiplexers

    Institute of Scientific and Technical Information of China (English)

    Yuanliang Chu(初元量); Hanyi Zhang(张汉一)

    2003-01-01

    The dimensions of input waveguide and output waveguide of arrayed waveguide gratings (AWGs) determinethe crosstalk, insertion loss and 1-dB bandwidth. In cascaded optical add/drop multiplexers (OADMs),the value of these parameters will largely affect the power penalty of system. The power penalty ofcascaded OADMs is calculated with different waveguide dimensions of AWGs in this paper. Consideringof wavelength misalignment, an optimization design of AWGs is obtained.

  9. Position-dependent coupling between a channel waveguide and a distorted microsphere resonator

    Science.gov (United States)

    Senthil Murugan, Ganapathy; Panitchob, Yuwapat; Tull, Elizabeth J.; Bartlett, Philip N.; Hewak, Daniel W.; Zervas, Michalis N.; Wilkinson, James S.

    2010-03-01

    Glass microsphere resonators have the potential to add significant functionality to planar lightwave circuits when coupled to waveguides where they can provide wavelength filtering, delay and low-power switching, and laser functions. Design of such photonic circuits requires precise coupling between spheres and waveguides to allow control of Q-factor and hence of stored energy and resonator bandwidth. In this paper an erbium-doped silicate glass microsphere is coupled to an ion-exchanged glass waveguide, and excitation spectra for the sphere whispering-gallery modes are determined as a function of spatial separation. Modal assignment allows extraction of the physical parameters of the microsphere and the dependence of Q-factor with separation is compared with theory. All practical microspheres exhibit a small degree of ellipticity and the effects of this upon whispering-gallery mode excitation and wavelength splitting are explored. It has been shown that appropriate displacement and orientation of slightly deformed microspheres with respect to the waveguide can be used to control the effective Q-factor and optimize the spectral shape of the optical devices. This can result in either single high-Q peaks or substantially broadened and spectrally flattened resonances.

  10. Real-time sensing of cell morphology by infrared waveguide spectroscopy.

    Directory of Open Access Journals (Sweden)

    Victor Yashunsky

    Full Text Available We demonstrate that a live epithelial cell monolayer can act as a planar waveguide. Our infrared reflectivity measurements show that highly differentiated simple epithelial cells, which maintain tight intercellular connectivity, support efficient waveguiding of the infrared light in the spectral region of 1.4-2.5 µm and 3.5-4 µm. The wavelength and the magnitude of the waveguide mode resonances disclose quantitative dynamic information on cell height and cell-cell connectivity. To demonstrate this we show two experiments. In the first one we trace in real-time the kinetics of the disruption of cell-cell contacts induced by calcium depletion. In the second one we show that cell treatment with the PI3-kinase inhibitor LY294002 results in a progressive decrease in cell height without affecting intercellular connectivity. Our data suggest that infrared waveguide spectroscopy can be used as a novel bio-sensing approach for studying the morphology of epithelial cell sheets in real-time, label-free manner and with high spatial-temporal resolution.

  11. Optimization of electron beam patterned hydrogen silsesquioxane mask edge roughness for low-loss silicon waveguides

    Science.gov (United States)

    Wood, Michael G.; Chen, Li; Burr, Justin R.; Reano, Ronald M.

    2014-01-01

    We carried out a multiparameter fabrication study designed to reduce the line edge roughness (LER) of electron beam (e-beam) patterned hydrogen silsesquioxane resist for the purpose of producing low-loss silicon strip waveguides. Reduced mask roughness was achieved for 50°C pre-exposure baking, 5000 μC/cm2 dose with a beam spot size more than twice as large as the electron beam step size, development in 25% tetramethylammonium hydroxide and postdevelopment baking with rapid thermal annealing in an O2 ambient at 1000°C. The LER caused by pattern fracturing and stage stitches was reduced with multipass writing and per-pass linear and rotational offsets. Si strip waveguides patterned with the optimized mask have root-mean-square sidewall roughness of 2.1 nm with a correlation length of 94 nm, as measured by three-dimensional atomic force microscopy. Measured optical propagation losses of these waveguides across the telecommunications C-band were 2.5 and 2.8 dB/cm for the transverse magnetic and transverse electric modes, respectively. These reduced loss waveguides enable the fabrication of advanced planar lightwave circuit topologies.

  12. Optical properties of K9 glass waveguides fabricated by using carbon-ion implantation

    Science.gov (United States)

    Liu, Chun-Xiao; Wei, Wei; Fu, Li-Li; Zhu, Xu-Feng; Guo, Hai-Tao; Li, Wei-Nan; Lin, She-Bao

    2016-07-01

    K9 glass is a material with promising properties that make it attractive for optical devices. Ion implantation is a powerful technique to form waveguides with controllable depth and refractive index profile. In this work, optical planar waveguide structures were fabricated in K9 glasses by using 6.0-MeV C3+-ion implantation with a fluence of 1.0 × 1015 ions/cm2. The effective refractive indices of the guided modes were measured by using a prism-coupling system. The refractive index change in the ion-irradiated region was simulated by using the intensity calculation method. The modal intensity profile of the waveguide was calculated and measured by using the finite difference beam propagation method and the end-face coupling technique, respectively. The transmission spectra before and after the implantation showed that the main absorption band was not influenced by the low fluence dopants. The optical properties of the carbon-implanted K9 glass waveguides show promise for use as integrated photonic devices.

  13. A current-matrix model for metallic and dielectric postwall waveguides

    Science.gov (United States)

    Coenen, T. J.; Bekers, D. J.; Tauritz, J. L.; van Vliet, F. E.

    2011-10-01

    Waveguide structure integration in planar substrates for use in microwave components has received considerable attention in recent years. Waveguides with side walls consisting of cylindrical posts (postwall waveguides or PWWGs) are of interest, since they are compatible with standard PCB fabrication technology and exhibit low loss. In this paper we present an electromagnetic model for PWWG building blocks, whose characteristics are described entirely in terms of equivalent electric and magnetic surface currents at predefined port interfaces consistent with Lorentz's reciprocity theorem. Introducing input and output surface currents, we determine the response of a block for a given port excitation. The expansion of the currents in terms of suitable bases results in a matrix that relates input and output currents. The scattering parameters of a building block are determined by expressing waveguide modes in terms of these bases. This facilitates the future integration of PWWG components in a microwave circuit simulator. We validate our model by comparing the results for simulated and measured uniform PWWGs implemented with metallic and dielectric posts.

  14. Waveguides with Absorbing Boundaries: Nonlinearity Controlled by an Exceptional Point and Solitons

    Science.gov (United States)

    Midya, Bikashkali; Konotop, Vladimir V.

    2017-07-01

    We reveal the existence of continuous families of guided single-mode solitons in planar waveguides with weakly nonlinear active core and absorbing boundaries. Stable propagation of TE and TM-polarized solitons is accompanied by attenuation of all other modes, i.e., the waveguide features properties of conservative and dissipative systems. If the linear spectrum of the waveguide possesses exceptional points, which occurs in the case of TM polarization, an originally focusing (defocusing) material nonlinearity may become effectively defocusing (focusing). This occurs due to the geometric phase of the carried eigenmode when the surface impedance encircles the exceptional point. In its turn, the change of the effective nonlinearity ensures the existence of dark (bright) solitons in spite of focusing (defocusing) Kerr nonlinearity of the core. The existence of an exceptional point can also result in anomalous enhancement of the effective nonlinearity. In terms of practical applications, the nonlinearity of the reported waveguide can be manipulated by controlling the properties of the absorbing cladding.

  15. Wideband unbalanced waveguide power dividers and combiners

    Energy Technology Data Exchange (ETDEWEB)

    Halligan, Matthew; McDonald, Jacob Jeremiah; Strassner, II, Bernd H.

    2016-05-17

    The various technologies presented herein relate to waveguide dividers and waveguide combiners for application in radar systems, wireless communications, etc. Waveguide dividers-combiners can be manufactured in accordance with custom dimensions, as well as in accordance with waveguide standards such that the input and output ports are of a defined dimension and have a common impedance. Various embodiments are presented which can incorporate one or more septum(s), one or more pairs of septums, an iris, an input matching region, a notch located on the input waveguide arm, waveguide arms having stepped transformer regions, etc. The various divider configurations presented herein can be utilized in high fractional bandwidth applications, e.g., a fractional bandwidth of about 30%, and RF applications in the Ka frequency band (e.g., 26.5-40 GHz).

  16. Design Procedure for Compact Folded Waveguide Filters

    DEFF Research Database (Denmark)

    Dong, Yunfeng; Johansen, Tom Keinicke; Zhurbenko, Vitaliy;

    Waveguide filters are widely used in communication systems due to low losses and high power handling capabilities. One drawback of the conventional waveguide filters is their large size, especially for low-frequency and high-order realizations. It has been shown that the footprint of conventional...... waveguide resonators can be reduced to one quarter by folding the electric and magnetic fields inside the cavity (J. S. Hong, Microwave Symposium Digest, 2004, Vol. 1, pp. 213-216). This paper presents a novel systematic procedure for designing compact low-loss bandpass filters by using folded waveguide...... resonators. As a design example, a scaled version of a filter specified for a TETRA (Terrestrial Trunked Radio) system has been considered. The folded waveguide filter is designed to fulfil specific requirements, and the design procedure can be easily applied to other folded waveguide filter designs...

  17. Plasmonic coaxial waveguide-cavity devices.

    Science.gov (United States)

    Mahigir, Amirreza; Dastmalchi, Pouya; Shin, Wonseok; Fan, Shanhui; Veronis, Georgios

    2015-08-10

    We theoretically investigate three-dimensional plasmonic waveguide-cavity structures, built by side-coupling stub resonators that consist of plasmonic coaxial waveguides of finite length, to a plasmonic coaxial waveguide. The resonators are terminated either in a short or an open circuit. We show that the properties of these waveguide-cavity systems can be accurately described using a single-mode scattering matrix theory. We also show that, with proper choice of their design parameters, three-dimensional plasmonic coaxial waveguide-cavity devices and two-dimensional metal-dielectric-metal devices can have nearly identical transmission spectra. Thus, three-dimensional plasmonic coaxial waveguides offer a platform for practical implementation of two-dimensional metal-dielectric-metal device designs.

  18. Systematic Design of Slow Light Waveguides

    DEFF Research Database (Denmark)

    Wang, Fengwen

    Light can propagate much slower in photonic crystal waveguides and plasmonic waveguides than in vacuum. Slow light propagation in waveguides shows broad prospects in the terabit communication systems. However, it causes severe signal distortions and displays large propagation loss. Moreover...... two different parameterizations. Detailed comparisons show that the bandwidth of slow light propagation can be significantly enhanced by allowing irregular geometries in the waveguides. To mitigate the propagation loss due to scattering in the photonic crystal waveg- uides, an optimization problem...... is formulated to minimize the average propagation loss of the designed modes. The presented approach is employed to design a free-topology slow light waveguide. Numerical result illustrates that slow light propagation in the optimized waveguide displays significantly suppressed propagation loss while keeping...

  19. Multilayer cladding with hyperbolic dispersion for plasmonic waveguides

    DEFF Research Database (Denmark)

    Babicheva, Viktoriia; Shalaginov, Mikhail Y.; Ishii, Satoshi;

    2015-01-01

    We study the properties of plasmonic waveguides with a dielectric core and multilayer metal-dielectric claddings that possess hyperbolic dispersion. The waveguides hyperbolic multilayer claddings show better performance in comparison to conventional plasmonic waveguides. © OSA 2015....

  20. Single-mode planar optics for 4-20um wavelengths astronomical interferometry

    Science.gov (United States)

    Laurent, E.; Kern, P.; Schanen, I.; Rousselet-Perraut, K.

    2002-06-01

    Single-mode planar optics for 4-20 micrometers wavelengths astronomical interferometry. Spatial filtering is a critical issue to achieve nulling interferometry in the framework of spatial missions aimed at the detection of exoplanets. Several working interferometric instruments take benefits of guided optics for spatial filtering in the near IR wavelengths and thus provide accurate visibility measurements. Futhermore planar optics would also provides beam combining functions within a single compact and stable device. Existing telecom technology allows beam combiner realizations for 0.8 to 1.6 micrometers wavelengths. Last works allow us to valid these technologies up to 2.4 micrometers for stellar interferometry in the H and K bands. Technological developments are required to meet the scientific domain of the spatial missions like IRSI/DARWIN and TPF dedicated to thermal infrared wavelengths [4-20 micrometers]. We present the most promising materials with their technologies to manufacture single-mode planar optics for this wavelength range. First set of solutions involved chalcogenide glasses. Channel waveguides could be manufactured by photo-exposition method or thin layer etching process. Another solution is using porous silicon obtained from an acid dissolution of a silicon substrate which allows refractive index modulation. The last set of solution is based on thin films etching of semiconductor materials like silicon, germanium, zinc sulfide and zinc selenide.Test benches for the single-mode behavior are also presented. For each solutions, we present some manufactured waveguides with their optical characterizations.

  1. Micellization and Characterization of Block Copolymer Detergents

    DEFF Research Database (Denmark)

    Hvidt, Søren

    Triblock copolymers of the type EPE, where E and P denote ethylene oxide and propylene oxide blocks, respectively, are used widely in industry as emulsifiers, anti-foaming agents, and in delayed drug release. EPE copolymers form micelles with a core of P blocks and different micellar shapes depen...

  2. Micellization and Characterization of Block Copolymer Detergents

    DEFF Research Database (Denmark)

    Hvidt, Søren

    Triblock copolymers of the type EPE, where E and P denote ethylene oxide and propylene oxide blocks, respectively, are used widely in industry as emulsifiers, anti-foaming agents, and in delayed drug release. EPE copolymers form micelles with a core of P blocks and different micellar shapes...

  3. Copolymers at the solid - liquid interface

    NARCIS (Netherlands)

    Wijmans, C.M.

    1994-01-01

    Copolymers consisting of both adsorbing and nonadsorbing segments can show an adsorption behaviour which is very different from that of homopolymers. We have mainly investigated the adsorption of AB diblock copolymers, which have one adsorbing block (anchor) and one nonadsorbing block

  4. Drug targeting to tumors using HPMA copolymers

    NARCIS (Netherlands)

    Lammers, T.G.G.M.

    2009-01-01

    Copolymers based on N-(2-hydroxypropyl)methacrylamide (HPMA) are prototypic and well-characterized polymeric drug carriers that have been broadly implemented in the delivery of anticancer agents. HPMA copolymers circulate for prolonged periods of time, and by means of the Enhance Permeability and Re

  5. Process-Accessible States of Block Copolymers

    Science.gov (United States)

    Sun, De-Wen; Müller, Marcus

    2017-02-01

    Process-directed self-assembly of block copolymers refers to thermodynamic processes that reproducibly direct the kinetics of structure formation from a starting, unstable state into a selected, metastable mesostructure. We investigate the kinetics of self-assembly of linear A C B triblock copolymers after a rapid transformation of the middle C block from B to A . This prototypical process (e.g., photochemical transformation) converts the initial, equilibrium mesophase of the A B B copolymer into a well-defined but unstable, starting state of the A A B copolymer. The spontaneous structure formation that ensues from this unstable state becomes trapped in a metastable mesostructure, and we systematically explore which metastable mesostructures can be fabricated by varying the block copolymer composition of the initial and final states. In addition to the equilibrium mesophases of linear A B diblock copolymers, this diagram of process-accessible states includes 7 metastable periodic mesostructures, inter alia, Schoen's F-RD periodic minimal surface. Generally, we observe that the final, metastable mesostructure of the A A B copolymer possesses the same symmetry as the initial, equilibrium mesophase of the A B B copolymer.

  6. Thermochemical characteristics of chitosan-polylactide copolymers

    Science.gov (United States)

    Goruynova, P. E.; Larina, V. N.; Smirnova, N. N.; Tsverova, N. E.; Smirnova, L. A.

    2016-05-01

    The energies of combustion of chitosan and its block-copolymers with different polylactide contents are determined in a static bomb calorimeter. Standard enthalpies of combustion and formation are calculated for these substances. The dependences of the thermochemical characteristics on block-copolymer composition are determined and discussed.

  7. PEO-related block copolymer surfactants

    DEFF Research Database (Denmark)

    Mortensen, K.

    2001-01-01

    Non-ionic block copolymer systems based on hydrophilic poly(ethylene oxide) and more hydrophobic co-polymer blocks are used intensively in a variety of industrial and personal applications. A brief description on the applications is presented. The physical properties of more simple model systems ...

  8. Reverse-symmetry waveguides: Theory and fabrication

    DEFF Research Database (Denmark)

    Horvath, R.; Lindvold, Lars René; Larsen, N.B.

    2002-01-01

    We present an extensive theoretical analysis of reverse-symmetry waveguides with special focus on their potential application as sensor components in aqueous media and demonstrate a novel method for fabrication of such waveguides. The principle of reverse symmetry is based on making the refractiv...... has the advantage of deeper penetration of the evanescent electromagnetic field into the cover medium, theoretically permitting higher sensitivity to analytes compared to traditional waveguide designs. We present calculated sensitivities and probing depths of conventional and reverse...

  9. Talbot Effect in Three Waveguide Arrays

    Institute of Scientific and Technical Information of China (English)

    LI Zhi; ZHOU Hai-Feng; YANG Jian-Yi; JIANG Xiao-Qing

    2008-01-01

    By taking the coupling between the non-neighbourhood waveguides into account, the coupling characteristic of three waveguide arrays is analysed. The strong coupling equation of three waveguides is dealt with Laplace transform and LU decomposition. The general field evolution equation is obtained by inversion of the Laplace transform. The results show that the self-imaging conditions (Talbot effect) do not satisfy in general. The theoretical predictions are in good agreement with the BPM simulations.

  10. Digital Waveguide Adiabatic Passage Part 1: Theory

    CERN Document Server

    Vaitkus, Jesse A; Greentree, Andrew D

    2016-01-01

    Spatial adiabatic passage represents a new way to design integrated photonic devices. In conventional adiabatic passage designs require smoothly varying waveguide separations. Here we show modelling of adiabatic passage devices where the waveguide separation is varied digitally. Despite digitisation, our designs show robustness against variations in the input wavelength and refractive index contrast of the waveguides relative to the cladding. This approach to spatial adiabatic passage opens new design strategies and hence the potential for new photonics devices.

  11. Analysis of piezoelectric ultrasonic transducers attached to waveguides using waveguide finite elements.

    Science.gov (United States)

    Loveday, Philip W

    2007-10-01

    A finite-element modeling procedure for computing the frequency response of piezoelectric transducers attached to infinite constant cross-section waveguides, as encountered in guided wave ultrasonic inspection, is presented. Two-dimensional waveguide finite elements are used to model the waveguide. Conventional three-dimensional finite elements are used to model the piezoelectric transducer. The harmonic forced response of the waveguide is used to obtain a dynamic stiffness matrix (complex and frequency dependent), which represents the waveguide in the transducer model. The electrical and mechanical frequency response of the transducer, attached to the waveguide, can then be computed. The forces applied to the waveguide are calculated and are used to determine the amplitude of each mode excited in the waveguide. The method is highly efficient compared to time integration of a conventional finite-element model of a length of waveguide. In addition, the method provides information about each mode that is excited in the waveguide. The method is demonstrated by modeling a sandwich piezoelectric transducer exciting a waveguide of rectangular cross section, although it could be applied to more complex situations. It is expected that the modeling method will be useful during the optimization of piezoelectric transducers for exciting specific wave propagation modes in waveguides.

  12. Optical Waveguide Sensing and Imaging

    CERN Document Server

    Bock, Wojtek J; Tanev, Stoyan

    2008-01-01

    The book explores various aspects of existing and emerging fiber and waveguide optics sensing and imaging technologies including recent advances in nanobiophotonics. The focus is both on fundamental and applied research as well as on applications in civil engineering, biomedical sciences, environment, security and defence. The main goal of the multi-disciplinarry team of Editors was to provide an useful reference of state-of-the-art overviews covering a variety of complementary topics on the interface of engineering and biomedical sciences.

  13. RF window assembly comprising a ceramic disk disposed within a cylindrical waveguide which is connected to rectangular waveguides through elliptical joints

    Science.gov (United States)

    Tantawi, Sami G.; Dolgashev, Valery A.; Yeremian, Anahid D.

    2016-03-15

    A high-power microwave RF window is provided that includes a cylindrical waveguide, where the cylindrical waveguide includes a ceramic disk concentrically housed in a central region of the cylindrical waveguide, a first rectangular waveguide, where the first rectangular waveguide is connected by a first elliptical joint to a proximal end of the cylindrical waveguide, and a second rectangular waveguide, where the second rectangular waveguide is connected by a second elliptical joint to a distal end of the cylindrical waveguide.

  14. Dielectric Covered Planar Antennas at Submillimeter Wavelengths for Terahertz Imaging

    Science.gov (United States)

    Chattopadhyay, Goutam; Gill, John J.; Skalare, Anders; Lee, Choonsup; Llombart, Nuria; Siegel, Peter H.

    2011-01-01

    Most optical systems require antennas with directive patterns. This means that the physical area of the antenna will be large in terms of the wavelength. When non-cooled systems are used, the losses of microstrip or coplanar waveguide lines impede the use of standard patch or slot antennas for a large number of elements in a phased array format. Traditionally, this problem has been solved by using silicon lenses. However, if an array of such highly directive antennas is to be used for imaging applications, the fabrication of many closely spaced lenses becomes a problem. Moreover, planar antennas are usually fed by microstrip or coplanar waveguides while the mixer or the detector elements (usually Schottky diodes) are coupled in a waveguide environment. The coupling between the antenna and the detector/ mixer can be a fabrication challenge in an imaging array at submillimeter wavelengths. Antennas excited by a waveguide (TE10) mode makes use of dielectric superlayers to increase the directivity. These antennas create a kind of Fabry- Perot cavity between the ground plane and the first layer of dielectric. In reality, the antenna operates as a leaky wave mode where a leaky wave pole propagates along the cavity while it radiates. Thanks to this pole, the directivity of a small antenna is considerably enhanced. The antenna consists of a waveguide feed, which can be coupled to a mixer or detector such as a Schottky diode via a standard probe design. The waveguide is loaded with a double-slot iris to perform an impedance match and to suppress undesired modes that can propagate on the cavity. On top of the slot there is an air cavity and on top, a small portion of a hemispherical lens. The fractional bandwidth of such antennas is around 10 percent, which is good enough for heterodyne imaging applications.The new geometry makes use of a silicon lens instead of dielectric quarter wavelength substrates. This design presents several advantages when used in the submillimeter

  15. STUDY ON POLYSULFONE-POLYESTER BLOCK COPOLYMERS

    Institute of Scientific and Technical Information of China (English)

    DING Youjun; QI Daquan

    1988-01-01

    Synthesis and characterization of a series of Polysulfone (PSF)-Polyester (PEs) block copolymers were studied.The degree of randomness (B) of these block copolymers was calculated from the intensities of their proton signals in 1H NMR spectra and lies in the region of 0 < B < 1. It was shown that the degree of randomness (B) and the average sequence length (L) in block copolymers were relatively dependent on the reaction conditions, various feed ratios and structure of diols.The phenomenon was observed, when the PSF-PEs block copolymers dissolved in different solvents they had different viscosities and molecular conformations.The PSF-PEs block copolymers had better solvent resistance than homo-polysulfone.

  16. A New Type of Terahertz Waveguides

    Institute of Scientific and Technical Information of China (English)

    LOU Shu-Qin; GUO Tie-Ying; FANG Hong; LI Hong-Lei; JIAN Shui-Sheng

    2006-01-01

    A new type of THz waveguides, which employs a solid polyethylene rod as the core and polyethylene tubes in a periodic array of square lattice as the cladding, is proposed. Optical properties of this new THz waveguide, especially in dispersion, confinement loss and single mode property, are investigated in detail with the plane wave expansion method and the beam propagation method. Numerical results demonstrate that the new THz waveguide can reach not only low dispersion but also low confinement loss at single mode propagation. Therefore, the square lattice structure is a better candidate as THz waveguides than the triangular ones.

  17. Microwave gas breakdown in elliptical waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Koufogiannis, I. D.; Sorolla, E., E-mail: eden.sorolla@epfl.ch; Mattes, M. [École Polytechnique Fédérale de Lausanne, Laboratoire d’Électromagnétisme et d' Acoustique (LEMA), Station 11, CH-1015 Lausanne (Switzerland)

    2014-01-15

    This paper analyzes the microwave gas discharge within elliptical waveguides excited by the fundamental mode. The Rayleigh-Ritz method has been applied to solve the continuity equation. The eigenvalue problem defined by the breakdown condition has been solved and the effective diffusion length of the elliptical waveguide has been calculated, what is used to find the corona threshold. This paper extends the microwave breakdown model developed for circular waveguides and shows the better corona withstanding capabilities of elliptical waveguides. The corona breakdown electric field threshold obtained with the variational method has been compared with the one calculated with the Finite Elements Method, showing excellent agreement.

  18. Design and Performance of a 2.7 THz Waveguide Tripler

    Science.gov (United States)

    Maiwald, Frank; Martin, S.; Bruston, J.; Maestrini, A.; Crawford, T.; Siegel, P. H.

    2001-01-01

    The design and performance of a 0.9 THz to 2.7 THz waveguide tripler are presented. An unusual split block configuration with parallel input and output waveguides accommodates a monolithic membrane diode (MoMeD) circuit. Submicron planar GaAs Schottky diodes in single and antiparallel pairs are implemented with matching filters on a 3-micrometer thick suspended substrate as part of the MoMeD structure. The filters are a combination of short hammerheads and high-low impedance elements. Only a few circuit variations have been measured to date. The best current performance shows an output power of 0.1 microW and an efficiency of 0.002% at the band center frequency of 2.55 THz.

  19. Design of a Compact X-Band Substrate Integrated Waveguide Directional Coupler

    Directory of Open Access Journals (Sweden)

    B. H. Ahmad

    2013-04-01

    Full Text Available This paper presented the design of four-port network directional coupler at X-band frequency (8.2-12.4 GHz by using substrate integrated waveguide (SIW technique. SIW appears few years backwhich provides an excellent platform in order to design millimeter-wave circuits such as filter, antenna,resonator, coupler and power divider. It offers great compensation for smaller size and can be easily integrated with other planar circuits. The fabrication process can simply be done by using standard Printed Circuit Board (PCB process where the cost of the manufacturing process will be reduced compared to the conventional waveguide. The directional coupler basically implemented at radar, satellite and point-to-point radio. The simulations for this SIW directional coupler design shows good performances with low insertion loss, low return loss, broad operational bandwidth and have high isolation.

  20. Re-expansion method for circular waveguide discontinuities: Application to concentric expansion chambers

    Science.gov (United States)

    Homentcovschi, Dorel; Miles, Ronald N.

    2012-01-01

    The paper applies the re-expansion method for analyzing planar discontinuities at the junction of two axi-symmetrical circular waveguides. The normal modes in the two waveguides are expanded at the junction plane into a system of functions accounting for velocity singularities at the corner points. As the new expansion has a high convergence order, only a few terms have to be considered for obtaining the solution of most practical problems. This paper gives the equivalent impedance accounting for nonplanar waves into a plane-wave analysis and also the scattering matrix describing the coupling of arbitrary modes at each side of the discontinuity valid in the case of many propagating modes in both sides of the duct. The last section applies the re-expansion technique to some concentric expansion chambers providing an explicit formula for the transmission loss coefficient. PMID:22352491

  1. Tunable hybridization at midzone and anomalous Bloch-Zener oscillations in optical waveguide ladders.

    Science.gov (United States)

    Zheng, Ming Jie; Wang, Gang; Yu, Kin Wah

    2010-12-01

    We have studied the optical oscillation and tunneling of light waves in optical waveguide ladders (OWLs) formed by two coupled planar optical waveguide arrays. For the band structure, a midzone gap is formed owing to band hybridization, and its wavenumber position can be tuned throughout the whole Brillouin zone, which is different from the Bragg gap. By imposing a gradient in the propagation constant in each array, Bloch-Zener oscillation (BZO) is realized with Zener tunneling between the bands occurring at the midzone, which is contrary to the common BZO with tunneling at the center or edge of the Brillouin zone. The occurrence of BZO is demonstrated by using the field-evolution analysis. The tunable hybridization at the midzone enhances the tunability of BZO in the OWLs. This Letter may offer new insights into the coherent phenomena in optical lattices.

  2. Low Loss Sol-Gel TiO2 Thin Films for Waveguiding Applications

    Directory of Open Access Journals (Sweden)

    Alexis Fischer

    2013-03-01

    Full Text Available TiO2 thin films were synthesized by sol-gel process: titanium tetraisopropoxide (TTIP was dissolved in isopropanol, and then hydrolyzed by adding a water/isopropanol mixture with a controlled hydrolysis ratio. The as prepared sol was deposited by “dip-coating” on a glass substrate with a controlled withdrawal speed. The obtained films were annealed at 350 and 500 °C (2 h. The morphological properties of the prepared films were analyzed by Scanning Electron Microscopy (SEM and Atomic Force Microscopy (AFM. The optical waveguiding properties of TiO2 films were investigated for both annealing temperature using m-lines spectroscopy. The refractive indices and the film thickness were determined from the measured effective indices. The results show that the synthesized planar waveguides are multimodes and demonstrate low propagation losses of 0.5 and 0.8 dB/cm for annealing temperature 350 and 500 °C, respectively.

  3. Simulation study on the effects of chemical structure and molecular size on the acceptor strength in poly(3-hexylthiophene)-based copolymer with alternating donor and acceptor for photovoltaic applications

    Science.gov (United States)

    Rassamesard, Areefen; Pengpan, Teparksorn

    2017-02-01

    This research assessed the effects of various chemical structures and molecular sizes on the simulated geometric parameters, electron structures, and spectroscopic properties of single-chain complex alternating donor-acceptor (D-A) monomers and copolymers that are intended for use as photoactive layer in a polymer solar cell by using Kohn-Sham density functional theory with B3LYP exchange-correlation functional. The 3-hexylthiophene (3HT) was selected for electron donor, while eight chemicals, namely thiazole (Z), thiadiazole (D), thienopyrazine (TP), thienothiadiazole (TD), benzothiadiazole (BT), thiadiazolothieno-pyrazine (TPD), oxadiazole (OXD) and 5-diphenyl-1,2,4-triazole (TAZ), were employed as electron acceptor functional groups. The torsional angle, bridge bond length, intramolecular charge transfer, energy levels, and molecular orbitals were analyzed. The simulation results reveal that the geometry and electron structure of donor-acceptor monomer and copolymer are significantly impacted by heterocyclic rings, heteroatoms, fused rings, degree of steric hindrance and coplanarity of the acceptor molecular structure. Planar conformation was obtained from the D copolymer, and a pseudo-planar structure with the TD copolymer. The TAZ acceptor exhibited strong steric hindrance due to its bulky structure and non-planarity of its structure. An analysis of the electron structures indicated that the degree of intramolecular electron-withdrawing capability had the rank order TAZ  group provides a compromise in the characteristics of a donor-acceptor copolymer, useful in a polymeric candidate material for the photoactive layer in a polymer solar cell.

  4. Rapid self-assembly of block copolymers to photonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Xia, Yan; Sveinbjornsson, Benjamin R; Grubbs, Robert H; Weitekamp, Raymond; Miyake, Garret M; Atwater, Harry A; Piunova, Victoria; Daeffler, Christopher Scot; Hong, Sung Woo; Gu, Weiyin; Russell, Thomas P.

    2016-07-05

    The invention provides a class of copolymers having useful properties, including brush block copolymers, wedge-type block copolymers and hybrid wedge and polymer block copolymers. In an embodiment, for example, block copolymers of the invention incorporate chemically different blocks comprising polymer size chain groups and/or wedge groups that significantly inhibit chain entanglement, thereby enhancing molecular self-assembly processes for generating a range of supramolecular structures, such as periodic nanostructures and microstructures. The present invention also provides useful methods of making and using copolymers, including block copolymers.

  5. All-optical switching in a symmetric three-waveguide coupler with phase-mismatched absorptive central waveguide.

    Science.gov (United States)

    Chen, Yijing; Ho, Seng-Tiong; Krishnamurthy, Vivek

    2013-12-20

    All-optical switching operation based on manipulation of absorption in a three-waveguide directional coupler is theoretically investigated. The proposed structure consists of one absorptive central waveguide and two identical passive side waveguides. Optically induced absorption change in the central waveguide effectively controls the coupling of light between the two side waveguides, leading to optical switching action. The proposed architecture alleviates the fabrication challenges and waveguide index matching conditions that limit previous demonstrations of similar switching schemes based on a two-waveguide directional coupler. The proposed device accommodates large modal index difference between absorptive and passive waveguides without compromising the switching extinction ratio.

  6. Characterization of Flexible Copolymer Optical Fibers for Force Sensing Applications

    Directory of Open Access Journals (Sweden)

    Lukas J. Scherer

    2013-09-01

    Full Text Available In this paper, different polymer optical fibres for applications in force sensing systems in textile fabrics are reported. The proposed method is based on the deflection of the light in fibre waveguides. Applying a force on the fibre changes the geometry and affects the wave guiding properties and hence induces light loss in the optical fibre. Fibres out of three different elastic and transparent copolymer materials were successfully produced and tested. Moreover, the influence of the diameter on the sensing properties was studied. The detectable force ranges from 0.05 N to 40 N (applied on 3 cm of fibre length, which can be regulated with the material and the diameter of the fibre. The detected signal loss varied from 0.6% to 78.3%. The fibres have attenuation parameters between 0.16–0.25 dB/cm at 652 nm. We show that the cross-sensitivies to temperature, strain and bends are low. Moreover, the high yield strength (0.0039–0.0054 GPa and flexibility make these fibres very attractive candidates for integration into textiles to form wearable sensors, medical textiles or even computing systems.

  7. NANOSTRUCTURES OF FUNCTIONAL BLOCK COPOLYMERS

    Institute of Scientific and Technical Information of China (English)

    Guojun Liu

    2000-01-01

    Nanostructure fabrication from block copolymers in my group normally involves polymer design, synthesis, selfassembly, selective domain crosslinking, and sometimes selective domain removal. Preparation of thin films with nanochannels was used to illustrate the strategy we took. In this particular case, a linear triblock copolymer polyisopreneblock-poly(2-cinnamoylethyl methacrylate)-block-poly(t-butyl acrylate), PI-b-PCEMA-b-PtBA, was used. Films, 25 to50μm thick, were prepared from casting on glass slides a toluene solution of PI-b-PCEMA-b-PtBA and PtBA homopolymer,hPtBA, where hPtBA is shorter than the PtBA block. At the hPtBA mass fraction of 20% relative to the triblock or the total PtBA (hPtBA and PtBA block) volume fraction of 0.44, hPtBA and PtBA formed a seemingly continuous phase in the matrix of PCEMA and PI. Such a block segregation pattern was locked in by photocrosslinking the PCEMA domain. Nanochannels were formed by extracting out hPtBA with solvent. Alternatively, larger channels were obtained from extracting out hPtBA and hydrolyzing the t-butyl groups of the PtBA block. Such membranes were not liquid permeable but had gas permeability constants ~6 orders of magnitude higher than that of low-density polyethylene films.

  8. Optimal geometry of nonlinear silicon slot waveguides accounting for the effect of waveguide losses.

    Science.gov (United States)

    Ong, Jun Rong; Chen, Valerian H

    2015-12-28

    The optimal geometry of silicon-organic hybrid slot waveguides is investigated in the context of the efficiency of four-wave mixing (FWM), a χ(3) nonlinear optical process. We study the effect of slot and waveguide widths, as well as waveguide asymmetry on the two-photon absorption (TPA) figure of merit and the roughness scattering loss. The optimal waveguide core width is shown to be 220nm (symmetric) with a slot width of 120nm, at a fixed waveguide height of 220nm. We also show that state-of-the-art slot waveguides can outperform rib waveguides, especially at high powers, due to the high TPA figure-of-merit.

  9. GeSn p-i-n waveguide photodetectors on silicon substrates

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Yu-Hsiang; Chang, Guo-En, E-mail: imegec@ccu.edu.tw [Department of Mechanical Engineering and Advanced Institute of Manufacturing with High-tech Innovations, National Chung Cheng University, Chia-Yi County 62102, Taiwan (China); Cheng, H. H. [Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan (China); Mashanov, Vladimir I. [Rzhanov Institute of Semiconductor Physics, Siberian Branch of the Russian Academy of Sciences, Lavrentjeva 13, Novosibirsk 630090 (Russian Federation)

    2014-12-08

    We report an investigation on GeSn p-i-n waveguide photodetectors grown on a Ge-buffered Si wafer. In comparison with a reference Ge detector, the GeSn detector shows an enhanced responsivity in the measured energy range, mainly attributed to the smaller bandgap caused by Sn-alloying. Analysis of the quantum efficiency indicates that increasing the Sn content in the active layers can significantly shorten the required device length to achieve the maximum efficiency. The present investigation demonstrates the planar photodetectors desired for monolithic integration with electronic devices.

  10. Active waveguides produced in lithium fluoride by He{sup +} implantation

    Energy Technology Data Exchange (ETDEWEB)

    Mussi, V. [Dip. Fisica and UdR INFM, Universita di Genova, V. Dodecaneso 33, 16146 Genova (Italy)]. E-mail: mussi@fisica.unige.it; Montereali, R.M. [ENEA, Advanced Physical Technologies, C.R. Frascati, V.E. Fermi 45, 00044 Frascati (Italy); Moretti, P. [LPCML, UMR 5620, CNRS Universite Lyon 1, 69622 Villeurbanne (France); Mugnier, J. [LPCML, UMR 5620, CNRS Universite Lyon 1, 69622 Villeurbanne (France); Nichelatti, E. [ENEA, Advanced Physical Technologies, C.R. Casaccia, V. Anguillarese 301, 00060 Rome (Italy); Somma, F. [Dip. Fis. and UdR INFM, Universita Roma Tre, V. della Vasca Navale 84, 00146 Rome (Italy); Jacquier, B. [LPCML, UMR 5620, CNRS Universite Lyon 1, 69622 Villeurbanne (France)

    2005-04-01

    Planar active waveguides were produced in lithium fluoride crystals by implantation with 1.5 MeV He{sup +} ions at several doses. The colored samples have been characterized by optical absorption, photoluminescence and m-line spectroscopy. By comparing the measured guided-mode effective indices with the ones calculated by means of the Chandler-Lama approach, the depth profile of refractive index was derived, showing that there are two competitive physical mechanisms, associated with different processes of energy deposition along the ion track, responsible for positive and negative modifications of the refractive index in the irradiated volume.

  11. Design of integrated scanning laser Doppler velocitmeter using arrayed waveguide gratings

    Science.gov (United States)

    Maru, Koichi; Fujii, Yusaku; Obokata, Tomio; Ishima, Tsuneaki; Yupapin, Preecha; Pornsuwancharoen, Nithitroth; Juthanggoon, Thanaprasert

    2009-07-01

    An integrated scanned differential LDV has been proposed using planar lightwave circuit (PLC) technology. By using the proposed LDV, the measurement position can be scanned in depth direction without any mechanical movement. The PLC technology is utilized in the proposed design for achieving a compact optical circuit. The characteristics of the proposed LDV are simulated with a design model based on grating equations for AWGs. The simulation result reveals that the measurement position can be changed over the range of 46 mm in the depth direction without mechanical movement when the displacement between output sides of two waveguide arrays is 30 mm.

  12. Coarse Grained Simulation of Lipid Membrane and Triblock Copolymers

    Science.gov (United States)

    Hatakeyama, Masaomi; Faller, Roland

    2008-02-01

    We investigated the interaction between DPPC (Dipalmitoyl phosphatidylcholine) bilayer and polyethylene oxide-polypropylene oxide-polyethylene oxide (PEO-PPO-PEO) triblock copolymers using coarse grained simulation. We simulated two systems of DPPC bilayer and PEO-PPO-PEO triblock copolymer containing different mole fractions, and simulated DPPC vesicle with the copolymers. We found different adsorption mechanisms of triblock copolymers depending on concentration. And we also observed docking process between a lipid vesicle and a micelle of the copolymers.

  13. Block copolymer membranes for aqueous solution applications

    KAUST Repository

    Nunes, Suzana Pereira

    2016-03-22

    Block copolymers are known for their intricate morphology. We review the state of the art of block copolymer membranes and discuss perspectives in this field. The main focus is on pore morphology tuning with a short introduction on non-porous membranes. The two main strategies for pore formation in block copolymer membranes are (i) film casting and selective block sacrifice and (ii) self-assembly and non-solvent induced phase separation (SNIPS). Different fundamental aspects involved in the manufacture of block copolymer membranes are considered, including factors affecting the equilibrium morphology in solid films, self-assembly of copolymer in solutions and macrophase separation by solvent-non-solvent exchange. Different mechanisms are proposed for different depths of the SNIPS membrane. Block copolymer membranes can be prepared with much narrower pore size distribution than homopolymer membranes. Open questions and indications of what we consider the next development steps are finally discussed. They include the synthesis and application of new copolymers and specific functionalization, adding characteristics to respond to stimuli and chemical environment, polymerization-induced phase separation, and the manufacture of organic-inorganic hybrids.

  14. Waveguide tapering for beam-width control in a waveguide transducer.

    Science.gov (United States)

    Kwon, Young Eui; Jeon, Hyun Joong; Kim, Hoe Woong; Kim, Yoon Young

    2014-03-01

    In a waveguide transducer that transmits an ultrasonic wave through a waveguide unit to a test structure, it is most preferred to send a non-dispersive ultrasonic wave of a narrow beam width. However, there is an unresolved conflict between the generation of the non- or less-dispersive wave and the transmission of a narrow-beam wave into a test structure. Among others, the thickness of the waveguide unit in a waveguide transducer is the key variable determining these two conflicting criteria, but the use of a uniformly-thick waveguide of any thickness cannot fulfill the two conflicting criteria simultaneously. In this study, we propose a specially-engineered tapered waveguide unit for the simultaneous satisfaction. An excitation unit is installed at the end of the thin region of the tapered waveguide and generates only the lowest non-dispersive shear-horizontal wave. Then the generated wave propagates through the tapered region of the waveguide unit and reaches the thick region of the waveguide with insignificant mode conversion to higher modes. If the tapered waveguide is used, the surviving lowest mode in the thick region of the waveguide is shown to carry most of the transmitted power and is finally propagated into a test structure. Because the beam size of the propagated wave and the thickness of the contacting waveguide region are inversely related, the thick contacting region of the tapered waveguide ensures narrow beam width. Numerical and experimental investigations were performed to check the effectiveness of the proposed waveguide-tapering approach.

  15. Hybrid-integrated coherent receiver using silica-based planar lightwave circuit technology

    Science.gov (United States)

    Kim, Jong-Hoi; Choe, Joong-Seon; Choi, Kwang-Seong; Youn, Chun-Ju; Kim, Duk-Jun; Jang, Sun-Hyok; Kwon, Yong-Hwan; Nam, Eun-Soo

    2011-12-01

    A hybrid-integrated coherent receiver module has been achieved using flip-chip bonding technology, consisting of a silica-based 90°-hybrid planar lightwave circuit (PLC) platform, a spot-size converter integrated waveguide photodiode (SSC-WG-PD), and a dual-channel transimpedance amplifier (TIA). The receiver module shows error-free operation up to 40Gb/s and OSNR sensitivity of 11.5 dB for BER = 10-3 at 25 Gb/s.

  16. Design, Fabrication and Properties of the Multimode Polymer Planar 1 x 2 Y Optical Splitter

    Directory of Open Access Journals (Sweden)

    V. Prajzler

    2012-12-01

    Full Text Available We report about design, fabrication and measurement of the properties of multimode 1 x 2 optical planar power splitter. The splitters were designed with help of OptiCAD software using ray tracing method. The dimensions of the splitters were then optimized for connecting standard Plastic Optical Fiber. Norland Optical Adhesives glues were used as optical waveguide layers and the design structures were completed by CNC engraving on Poly(methyl methacrylate or Poly(methylmethacrylimide substrate. The devices have the insertion loss around 7.6 dB at 650 nm and the coupling ratio was 52:48.

  17. Broadband and total autocollimation of spin waves using planar magnonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, D.; Adeyeye, A. O. [Information Storage Materials Laboratory, Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576 (Singapore)

    2015-04-14

    We present a systematic study of spin wave autocollimation in planar magnonic crystals comprising of antidot arrays in nanoscale permalloy (Py: Ni{sub 80}Fe{sub 20}) thin films. It is shown that a careful design of such crystals can allow for the autocollimation of the entire spin wave spectrum without any significant evanescence or any drop in the group velocity. These developments allow us access to spin wave beams which do not disperse or converge outside a waveguide. Collimated spin wave beams would be essential in applications such as dense signal routing and multiplexing in higher dimensional magnonic systems.

  18. Compact silica-on-silicon planar lightwave circuits for high speed optical signal processing

    Science.gov (United States)

    Callender, C. L.; Dumais, P.; Blanchetiere, C.; Jacob, S.; Ledderhof, C.; Smelser, C. W.; Yadav, K.; Albert, J.

    2012-02-01

    Silica-on-silicon planar lightwave circuit (PLC) technology is well established and provides a low loss and stable photonic device platform. However, limitations in size and integration of active components remain. Engineering of the layer structure in silica PLCs to achieve high-index contrast, compact device architectures and monolithically integrated optical nonlinearities is described. Modeling of properties of doped-silica layers provides a design strategy for optimization of waveguide loss and birefringence. Optical nonlinearities in poled silica layers have been demonstrated, and recent work to incorporate these into functional device structures and exploit them for high speed modulation is reported.

  19. Optical waveguides formed by silver ion exchange in Schott SG11 glass for waveguide evanescent field fluorescence microscopy: evanescent images of HEK293 cells

    Science.gov (United States)

    Hassanzadeh, Abdollah; Nitsche, Michael; Armstrong, Souzan; Nabavi, Noushin; Harrison, Rene; Dixon, S. Jeffrey; Langbein, Uwe; Mittler, Silvia

    2010-05-01

    Planar glass waveguides with a specific number of modes were fabricated by Ag+-Na+ exchange in Schott SG11 glass. The effective refractive indices were determined using m-line spectroscopy in both s- and p-polarization. By using the reversed Wentzel-Kramers-Brillouin approximation, the index profiles were described by a nonlinear diffusion equation. The diffusion coefficients for Ag+ were established, as well as the penetration depth of the evanescent field in an aqueous environment for the different modes. The integrals of |E|2 fields for the evanescent-guided fields were investigated. These are important when evanescent fields are used for illumination in interface microscopy, an alternative method to total internal reflection fluorescence (TIRF) microscopy. The photoluminescent behavior of the waveguides was investigated as a function of ion exchange time and excitation wavelengths. Comparable images were obtained of fluorescently labeled HEK293 cells using TIRF microscopy and waveguide evanescent field fluorescence microscopy. Imaging was performed using HEK293 cells, delivering similar images and information.

  20. Design of a Slab Waveguide Multiaperture Fourier Spectrometer for Water Vapor Measurements in Earth's Atmosphere

    Science.gov (United States)

    Sinclair, Kenneth; Florjańczyk, Mirosław; Solheim, Brian; Scott, Alan; Quine, Ben; Cheben, Pavel

    Concept, theory and design of a new type of waveguide device, a multiaperture Fourier-transform planar waveguide spectrometer[1], implemented as a prototype instrument is pre-sented. The spectrometer's objective is to demonstrate the ability of the new slab waveguide technology for application in remote sensing instruments[2]. The spectrometer will use a limb viewing configuration to detect the 1.36um waveband allowing concentrations of water vapor in earth's atmosphere to be measured[3]. The most challenging aspects of the design, assembly and calibration are presented. Focus will be given to the effects of packaging the spectrometer and interfacing to the detector array. Stress-induced birefringence will affect the performance of the waveguides, therefore the design of a stress-free mounting over a range of temperatures is important. Spectral retrieval algo-rithms will have to correct for expected fabrication errors in the waveguides. Data processing algorithms will also be developed to correct for non-uniformities of input brightness through the array, making use of MMI output couplers to capture both the in-phase and anti-phase interferometer outputs. A performance assessment of an existing breadboard spectrometer will demonstrate the capability of the instrument. REFERENCES 1. M. Florjáczyk, P. Cheben, S. Janz, A. Scott, B. Solheim, and D.-X. Xu, "Multiaper-n ture planar waveguide spectrometer formed by arrayed Mach-Zehnder interferometers," Opt. Expr. 15(26), 18176-18189 (2007). 2. M. Florjáczyk, P. Cheben, S. Janz, B. Lamontagne, J. n Lapointe, A. Scott, B. Solheim, and D.-X. Xu, "Slab waveguiode spatial heterodyne spectrom-eters for remote sensing from space," Optical sensors 2009. Proceedings of the SPIE, Volume 7356 (2009)., pp. 73560V-73560V-7 (2009). 3. A. Scott, M. Florjáczyk, P. Cheben, S. Janz, n B. Solheim, and D.-X. Xu, "Micro-interferometer with high throughput for remote sensing." MOEMS and Miniaturized Systems VIII. Proceedings of the SPIE