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Crystal Fibers (crystal + fiber)

Distribution by Scientific Domains
Physics and Astronomy46%
Engineering30%
Chemistry15%

Kinds of Crystal Fibers

  • photonic crystal fiber
    		•

    Selected Abstracts

    Photonic Crystal Fibers and Their Applications

    IEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 6 2009
    Osamu Tohyama Member
    Abstract Dramatic advances in research and development on photonic crystal fibers (PCF) have created new properties that had not been achievable using conventional fibers. PCFs have many fascinating features. The very high relative refractive index between the fiber core and air-hole cladding enables several prominent properties, notably endlessly single-mode (ESM) operation, high nonlinearity, wide-ranging dispersion management, and the ability to maintain high polarization. The processes involved in manufacturing PCFs are quite different from those used to manufacture conventional fibers, and this is largely because of the profusion of air holes in the silica glass that comprises PCFs. The authors have optimized the technology to manufacture photonic crystals with the required optical characteristics. This paper describes the properties and application of large-mode and ESM guidance, nonlinearity, and double cladding. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source]

    Supercontinuum generation up to 2.5 ,m in photonic crystal fiber made of lead-bismuth-galate glass

    LASER PHYSICS LETTERS, Issue 9 2010
    R. Buczynski
    Abstract In this paper we report on successful supercontinuum generation extending from the near to the mid-infrared region in the range 700,2500 nm in a micro-structured fiber made of lead-bismuth-galate glass and pumped in the femtosecond regime with a wavelength of 1540 nm. The flatness of 5 dB is observed in most of the registered spectrum 1000 , 2500 nm. The improved spectral and thermo-physical properties of this custom made lead-bismuth-galate glass against tellurite and commercially available heavy oxide SF-57 glasses are presented. (© 2010 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

    Transportation of nanosecond laser pulses by hollow core photonic crystal fiber for laser ignition

    LASER PHYSICS LETTERS, Issue 11 2005
    A. H. Al-Janabi
    Abstract Laser ignition via hollow core photonic crystal fiber (PCF) as a delivery medium has been demonstrated in the present work. Minimum pulse energy from a Q-switched Nd:YAG laser of only 150 µJ was achieved to ignite rich fuel mixtures of methane-air. Aspheric lens of high numerical aperture has been used to focus the laser beam. Different air/fuel ratios have been examined with different gas temperatures. The results indicate the feasibility of using hollow core PCF for high power beam transmission for laser ignition applications. (© 2005 by Astro, Ltd. Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

    Photochemistry in Photonic Crystal Fiber Nanoreactors

    CHEMISTRY - A EUROPEAN JOURNAL, Issue 19 2010
    Jocelyn S.
    Abstract We report the use of a liquid-filled hollow-core photonic crystal fiber (PCF) as a highly controlled photochemical reactor. Hollow-core PCFs have several major advantages over conventional sample cells: the sample volume per optical path length is very small (2.8,nL,cm,1 in the fiber used), long optical path lengths are possible as a result of very low intrinsic waveguide loss, and furthermore the light travels in a diffractionless single mode with a constant transverse intensity profile. As a proof of principle, the (very low) quantum yield of the photochemical conversion of vitamin B12, cyanocobalamin (CNCbl) to hydroxocobalamin ([H2OCbl]+) in aqueous solution was measured for several pH values from 2.5 to 7.5. The dynamics of the actively induced reaction were monitored in real-time by broadband absorption spectroscopy. The PCF nanoreactor required ten thousand times less sample volume compared to conventional techniques. Furthermore, the enhanced sensitivity and optical pump intensity implied that even systems with very small quantum yields can be measured very quickly,in our experiments one thousand times faster than in a conventional cuvette. [source]

    Influence of the atmosphere on the growth of LiYF4 single crystal fibers by the micro-pulling-down method

    CRYSTAL RESEARCH AND TECHNOLOGY, Issue 2 2009
    D. Maier
    Abstract Micro-pulling-down growth of LiYF4 single crystal fibers have been performed under different gas atmospheres using stoichiometric LiYF4 single crystal pieces from prior Czochralski experiments as starting material. Completely transparent and phase pure LiYF4 single crystal fibers could be obtained after evacuation of the recipient to 2×10 -6 mbar and subsequent filling with pure (99.995%) CF4 gas. Using a gas mixture of 5% CF4 in Argon or pure 5N Argon leads to the formation of micro crystallites of oxofluorides on the surface. Evacuating only to 3 × 10 -3 mbar leads, independently of atmosphere, to completely white fibers that are heavily contaminated with oxofluorides. DSC measurements of the completely transparent fiber grown under pure CF4 atmosphere reveal congruent melting behavior. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Growth and characterization of LiF single crystal fibers

    CRYSTAL RESEARCH AND TECHNOLOGY, Issue 12 2006
    M. Alshourbagy
    Abstract Single crystal LiF fibers have been grown by the micro-pulling-down (µ-PD) technique. The fibers are 0.6 mm in diameter and 100 mm in length and of good optical quality. We describe the experimental apparatus for growth and analyze the sample structure and its spectroscopic characteristics. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Photonic Crystal Fibers and Their Applications

    IEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 6 2009
    Osamu Tohyama Member
    Abstract Dramatic advances in research and development on photonic crystal fibers (PCF) have created new properties that had not been achievable using conventional fibers. PCFs have many fascinating features. The very high relative refractive index between the fiber core and air-hole cladding enables several prominent properties, notably endlessly single-mode (ESM) operation, high nonlinearity, wide-ranging dispersion management, and the ability to maintain high polarization. The processes involved in manufacturing PCFs are quite different from those used to manufacture conventional fibers, and this is largely because of the profusion of air holes in the silica glass that comprises PCFs. The authors have optimized the technology to manufacture photonic crystals with the required optical characteristics. This paper describes the properties and application of large-mode and ESM guidance, nonlinearity, and double cladding. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source]

    Experiment and simulation on interface shapes of an yttrium aluminium garnet miniature molten zone formed using the laser-heated pedestal growth method for single-crystal fibers

    JOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 4 2009
    P. Y. Chen
    A two-dimensional simulation was employed to study the melt/air and melt/solid interface shapes of the miniature molten zone formed in a laser-heated pedestal growth (LHPG) system. Using a non-orthogonal body-fitting grid system with the control-volume finite-difference method, the interface shape can be determined both efficiently and accurately. During stable growth, the dependence of the molten-zone length and shape on the heating CO2 laser is examined in detail under both the maximum and the minimum allowed powers with various growth speeds. The effect of gravity on the miniature molten zone is also simulated and the possibility of horizontally oriented LHPG is revealed. Such a horizontal system is good for the growth of long crystal fibers. [source]

    Simple models for predicting transmission properties of photonic crystal fibers

    MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 7 2006
    Rachad Albandakji
    Abstract Simple, fast, and efficient 1D models for evaluating the transmission properties of photonic crystal fibers are proposed. Using these models, axial propagation constant, chromatic dispersion, effective area, and leakage loss can be predicted with a reasonable accuracy but much faster than often time-consuming 2D analytical and numerical techniques and with much less computational resources. It is shown that the results are in good agreement with the published data available in the literature. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1286,1290, 2006; Published online in Wiley InterScience (www. interscience.wiley.com). DOI 10.1002/mop.21624 [source]

    Electron Backscatter Diffraction Study of Brachiopod Shell Calcite , Microscale Phase and Texture Analysis of a Polycrystalline Biomaterial

    PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION, Issue 5-6 2008
    Wolfgang W. Schmahl
    Abstract Electron backscatter diffraction (EBSD) is an easy to use and highly automated microdiffraction method suitable for the determination of crystallographic phase and crystallite orientation. The high level of hierarchical structural organization in the shells of marine organisms was studied. Calcite brachiopod shell materials were found to belong to three types of microstructure: nano- to microcrystalline layers of acicular crystals, fiber composites with calcite single crystal fibers with [uv0] morphological axes, and material formed by columnar crystals with [001] morphological axes selected by competitive growth. [source]