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Planar Waveguide (planar + waveguide)
Selected AbstractsImprovement of the Optical Transmission of Polymer Planar Waveguides by Plasma TreatmentPLASMA PROCESSES AND POLYMERS, Issue 3 2008Aissam Airoudj Abstract The aim of the present work is to reduce the optical losses of glycidyl ether of bisphenol A (SU-8) polymer planar waveguides using cold plasmas, which allow the substitution of H atoms by F. CF4 and mixtures of CF4/H2 RF plasma treatments were carried out for the surface fluorination of the SU-8 waveguide. The observed decrease in the optical losses due to propagation in the Si/SiO2/fluorinated SU-8 planar waveguides has been correlated with the surface fluorination as measured by XPS and CA measurements. In order to understand and to optimize the fluorination process, the plasma phase was analyzed by OES. Finally, the thickness of the fluorinated layer was estimated using modulated incident-angle XPS. [source] Light propagation and scattering in porous silicon nanocomposite waveguidesPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 8 2005P. Pirasteh Abstract Planar waveguides have been achieved from oxidised porous silicon layers (OPS) which have been impregnated by solvents, Congo Red (CR) dye and poly(p-phenylene vinylene) (PPV) polymer. Optical loss has been investigated by a simple technique based on surface optical scattering measurements. Optical loss has been studied as a function of the wavelength, impregnation type and CR concentration. The main sources of attenuation, such as absorption, scattering from interface roughness, scattering from nano- crystallites and modification of the refractive indexes after filling are discussed. Optical loss measured at 0.633 µm is about 1.8 dB/cm for the OPS waveguides The optical loss decreases with wavelength. Otherwise, the optical loss increases with the concentration of Congo Red dye which is absorbent at this wavelength. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Potential Modulated Attenuated Total Reflectance Spectroscopy of Prussian Blue Films on ITOISRAEL JOURNAL OF CHEMISTRY, Issue 3 2006Zeynep Ozkan Araci Potential modulated attenuated total reflectance (PM-ATR) spectroscopy has been employed to study charge transfer processes in Prussian blue (PB) films deposited on indium tin oxide (ITO) electrodes. PM-ATR is a planar waveguide-based spectroelectrochemical technique in which the optical response of an electroactive film is measured as a function of applied potential and modulation frequency. The multiple internal reflection geometry of PM-ATR provides a significant sensitivity advantage over the single external reflectance geometry that has been employed in most prior electroreflectance studies. The apparent electron transfer rate of PB on ITO obtained using PM-ATR was compared to that obtained with conventional cyclic voltammetry; the respective rates, 0.33 ± 0.15 s,1 (n = 3) and 0.71 ± 0.37 s,1 (n = 10), are in good agreement. [source] Evanescent fields,Direct measurement, modeling, and applicationMICROSCOPY RESEARCH AND TECHNIQUE, Issue 3 2007S.T. Huntington Abstract The evanescent field surrounding an exposed planar waveguide in silica is accurately measured using scanning near field optical microscopy (SNOM) and compared to models of the field distribution. Distortions in the field due to edge effects and the proximity of the mode to the surface are all detected. The characterized field is use to quantitatively explore the difference in collection efficiency between contact mode SNOM and intermittent contact mode SNOM. A strong correlation between tip oscillation amplitude and detection efficiency is determined. Microsc. Res. Tech., 2007. © 2007 Wiley-Liss, Inc. [source] Tunable erbium-doped fiber ring laser based on coupling between side-polished fiber and sliding tapered planar waveguideMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 4 2007Dong-Ho Lee Abstract A tunable erbium-doped fiber ring laser was made using a tunable side-polished fiber (SPF) filter with a tapered planar waveguide (PWG). The thickness of the tapered PWG varied because it slides laterally on the side-polished region. The proposed SPF filter does not need additional physical energy after resonant wavelength selected. Tuning direction of SPF filter is not limited. In addition, the proposed SPF filter can change the tuning resolution by changing the tapered angle of PWG. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 887,889, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22273 [source] Prism coupling characterization of planar optical waveguides made by silver ion exchange in glassPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 10 2005O. Hidalgo Abstract A modified dark-lines method of prism-coupling technique is utilized for the experimental determination of the effective index of propagating modes in a glass planar waveguide. We use to make the waveguides a silver-sodium ion exchange in a nitrate solution and sodalime glass as substrate (microscope slides). The measurements were accomplished by direct HeNe laser beam incidence and sensing the reflected light by a Thorlabs Dec110 optical detector linked to a Protek500 digital multimeter. A LabView virtual instrument was implemented for the automation of the measurement process. The effective indexes measured have been used to calculate the refractive index profile by IWKB method. A comparison with other results shows that our experimental setup is suitable for slab waveguide modes characterization. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Refractive index-modulated grating in two-mode planar polymeric waveguide produced by two-photon polymerizationPOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 7 2007Yi Dong Abstract A polymeric waveguide film was manufactured by spinning the materials on quartz substrate. Two-photon-initiated photopolymerization was carried out by tight-focusing femtosecond laser pulses in the two-mode planar waveguide. A typical index-modulated grating of 2.5,×,2,mm areas without morphology was fabricated. The results show that peak-to-peak modulation depth of the surface profile of grating region was only about 7,nm. The diffraction efficiency (DE) of the grating with a spacing period 2,µm was 0.17% and the corresponding index modulation reached 5.7,×,10,3. Copyright © 2007 John Wiley & Sons, Ltd. [source] Low-dose ion implanted active waveguides in Nd3+ doped near-stoichiometric lithium niobate: promising candidates for near infrared integrated laserPHYSICA STATUS SOLIDI - RAPID RESEARCH LETTERS, Issue 3 2008Feng Chen Abstract By applying low-dose oxygen ion implantation, active planar waveguides in Nd3+ doped near-stoichiometric lithium niobate laser crystals have been, for the first time to our knowledge, successfully produced. The waveguide exhibits good transmission properties with relatively low propagation loss of ,2 dB/cm. The confocal micro-luminescence investigations indicate that the emission properties of Nd3+ ions in the waveguide are well preserved with respect to the bulk, thus showing promising potentials for efficient waveguide laser action operating at the Nd3+ near-infrared bands. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Strong exciton-light coupling in photonic crystal nanocavitiesPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 2 2005Dario Gerace Abstract The strong coupling regime between excitons in a single self-assembled InAs quantum dot and the cavity mode in a photonic-crystal structure embedded in GaAs planar waveguides is theoretically investigated. It is concluded that zero-dimensional mixed states should form when the quality factor of the cavity mode is higher than Q , 2000. The corresponding vacuum-field Rabi splitting is close to its limiting value already for Q , 10000. Results are shown for a model GaAs-based photonic crystal nanocavity, in which single quantum dot excitons are predicted to be always in the strong coupling regime if the quantum dot is placed close to the antinode position of the electric field. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Improvement of the Optical Transmission of Polymer Planar Waveguides by Plasma TreatmentPLASMA PROCESSES AND POLYMERS, Issue 3 2008Aissam Airoudj Abstract The aim of the present work is to reduce the optical losses of glycidyl ether of bisphenol A (SU-8) polymer planar waveguides using cold plasmas, which allow the substitution of H atoms by F. CF4 and mixtures of CF4/H2 RF plasma treatments were carried out for the surface fluorination of the SU-8 waveguide. The observed decrease in the optical losses due to propagation in the Si/SiO2/fluorinated SU-8 planar waveguides has been correlated with the surface fluorination as measured by XPS and CA measurements. In order to understand and to optimize the fluorination process, the plasma phase was analyzed by OES. Finally, the thickness of the fluorinated layer was estimated using modulated incident-angle XPS. [source] | |||||||||||||