Download or read book Nonlinear Optical and Charge Distribution Studies Probing Electric Field Effects in Polymer Thin Films for Second Order Nonlinear Optical Applications written by and published by . This book was released on 1996 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goals of the research are two fold; First, determine the internal electric field effects from studies of charge magnitude, symmetry and distribution in dye-doped polymer systems. Second, a better understanding of the electric field effects on the chromophore mobility during and after poling. To this end, several techniques are being employed. Electrochromism technique is being used to determine the charge magnitude inside film samples. The films are 4-dimethylamino-4'-nitrostilbene and disperse red 1 chromophores doped into poly(Methyl methacrylate) guest-host systems. Charge symmetry is also being studies using thermal pulse experiments. Preliminary result show that the charges are distributed linearly in the sample. More tests will be performed in search of any local charge distribution inhomogeneities. An interferometric technique with in-situ poling was used to probe the poling field- induced molecular alignment of the chromophores as a function of temperature. Results are showing the dependence of poling on electric fields (magnitude and polarity). Integrated systems will further reveal the loses in the films due to the field Dependent chromophore orientation.

Download or read book Nonlinear Optical and Charge Distribution Studies Probing Electric Field Effects in Polymer Thin Films for Second Order Nonlinear Optics written by and published by . This book was released on 1994 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of large magnitude electric fields on polymer thin films is investigated in order to improve poling efficiencies in polymer films for second order nonlinear optical applications. This research determines the charge distribution, symmetry, and magnitude across doped and undoped glassy polymer thin films as a function of temperature, time, and poling (processing). Electrochromism, second order nonlinear optics, dielectric relaxation, isothermal current and surface voltage decay measurements will be used to determine the material properties. Trapping levels and sites will also be examined. By using dielectric relaxation and optical techniques we will explore how applied electric fields affect rotational mobility of small chromophores in polymer hosts. We expect to be able to improve poling efficiency and thus device performance both by achieving the greatest possible fields with the best magnitude and symmetry characteristics, and enhancing the temporal and thermal properties of the films by manipulating their charge storage and transport properties. This understanding will allow the most efficient development and design for nonlinear optical materials. Second Order Nonlinear Optical Polymers, Electric field Effects, Polymer Dynamics.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Announcements Index written by and published by . This book was released on 1995 with total page 840 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Annual Index written by and published by . This book was released on 1994 with total page 1746 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optics of Conducting Polymer Thin Films and Nanostructures written by Shangzhi Chen and published by Linköping University Electronic Press. This book was released on 2021-02-19 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: Intrinsically conducting polymers forms a category of doped conjugated polymers that can conduct electricity. Since their discovery in the late 1970s, they have been widely applied in many fields, ranging from optoelectronic devices to biosensors. The most common type of conducting polymers is poly(3,4-ethylenedioxythiophene), or PEDOT. PEDOT has been popularly used as electrodes for solar cells or light-emitting diodes, as channels for organic electrochemical transistors, and as p-type legs for organic thermoelectric generators. Although many studies have been dedicated to PEDOT-based materials, there has been a lack of a unified model to describe their optical properties across different spectral ranges. In addition, the interesting optical properties of PEDOT-based materials, benefiting from its semi-metallic character, have only been rarely studied and utilized, and could potentially enable new applications. Plasmonics is a research field focusing on interactions between light and metals, such as the noble metals (gold and silver). It has enabled various opportunities in fundamental photonics as well as practical applications, varying from biosensors to colour displays. This thesis explores highly conducting polymers as alternatives to noble metals and as a new type of active plasmonic materials. Despite high degrees of microstructural disorder, conducting polymers can possess electrical conductivity approaching that of poor metals, with particularly high conductivity for PEDOT deposited via vapour phase polymerization (VPP). In this thesis, we systematically studied the optical and structural properties of VPP PEDOT thin films and their nanostructures for plasmonics and other optical applications. We employed ultra-wide spectral range ellipsometry to characterize thin VPP PEDOT films and proposed an anisotropic Drude-Lorentz model to describe their optical conductivity, covering the ultraviolet, visible, infrared, and terahertz ranges. Based on this model, PEDOT doped with tosylate (PEDOT:Tos) presented negative real permittivity in the near infrared range. While this indicated optical metallic character, the material also showed comparably large imaginary permittivity and associated losses. To better understand the VPP process, we carefully examined films with a collection of microstructural and spectroscopic characterization methods and found a vertical layer stratification in these polymer films. We unveiled the cause as related to unbalanced transport of polymerization precursors. By selection of suitable counterions, e.g., trifluoromethane sulfonate (OTf), and optimization of reaction conditions, we were able to obtain PEDOT films with electrical conductivity exceeding 5000 S/cm. In the near infrared range from 1 to 5 µm, these PEDOT:OTf films provided a well-defined plasmonic regime, characterized by negative real permittivity and lower magnitude imaginary component. Using a colloidal lithography-based approach, we managed to fabricate nanodisks of PEDOT:OTf and showed that they exhibited clear plasmonic absorption features. The experimental results matched theoretical calculations and numerical simulations. Benefiting from their mixed ionic-electronic conducting characters, such organic plasmonic materials possess redox-tunable properties that make them promising as tuneable optical nanoantennas for spatiotemporally dynamic systems. Finally, we presented a low-cost and efficient method to create structural colour surfaces and images based on UV-treated PEDOT films on metallic mirrors. The concept generates beautiful and vivid colours through-out the visible range utilizing a synergistic effect of simultaneously modulating polymer absorption and film thickness. The simplicity of the device structure, facile fabrication process, and tunability make this proof-of-concept device a potential candidate for future low-cost backlight-free displays and labels.

Download or read book Polymers for Photonics Applications II written by Kwang-Sup Lee and published by Springer. This book was released on 2003-07-03 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: The future of information technology requires ultra high speed processing and large data storage capacity. Since the electronics technology using semi conduc tors and inorganic materials is about to reach its limits, much current research is focused on utilizing much faster photons than electrons, namely photonics. To achieve any significant effect on the actual use of the science of photonics, devel opments of more efficient photonics materials, better optical property evaluations, manufacture of devices for system applications, etc. are the subjects which need to be explored. In particular, the development of photonics materials stands in the forefront of research as this constitutes the most pertinent factor with regard to the development of ultra high speed and large capacity information processing. In this respect, there has been continuous research on photo responsive materials through molecular structure design and architecture and the results so far are very promising as functions and performances are beginning to realize their high expectations. The two special volumes "Polymers for Photonics Applications" give authorita tive and critical reviews on up to date activities in various fields of photonic poly mers including their promising applications. Seven articles have been contributed by internationally recognized and they deal with, polymers for second and third order nonlinear optics, quadratic parametric interactions in polymer waveguides, electroluminescent polymers as light sources, photoreflective polymers for holo graphic information storage, and highly efficient two photon absorbing organics and polymers.

Download or read book Physics Briefs written by and published by . This book was released on 1993 with total page 1058 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Beaux meubles anciens et de style written by and published by . This book was released on 1961 with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Photoinduced Modifications of the Nonlinear Optical Response in Liquid Crystalline Azopolymers written by Raquel Alicante and published by Springer Science & Business Media. This book was released on 2012-09-28 with total page 209 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study of the molecular response of a variety of push-pull organic compounds offers a starting point for macroscopic-scale investigation of azobenzene-based liquid crystalline polymeric films and their blends with highly efficient NLO chromophores.

Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 1048 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Electric Field Induced Effects in Polymer dye Films written by Lorina Lynn Poland and published by . This book was released on 1990 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Polymers for Second order Nonlinear Optics written by Geoffrey A. Lindsay and published by . This book was released on 1995 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents the most recent developments in second-order nonlinear optical polymers. Covers the most important technologies necessary to achieve commercially viable devices based on special polymeric materials with second-order nonlinear optical properties. Discusses important molecular design considerations, how to process the polymers into films, the stability of the films, their optical properties, and prototype devices that can be made from these films.

Download or read book Optical Properties of Poled Polymeric Thin Films written by Mohammad Ali Mortazavi and published by . This book was released on 1989 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Electrical Electronics Abstracts written by and published by . This book was released on 1997 with total page 1904 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nonlinear Optical Processes in Polymer Films written by and published by . This book was released on 1994 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electrooptic organic polymer thin films show great promise for applications in integrated optoelectronic devices. These materials are usually formed as guest-host polymer systems that exhibit large second order nonlinear optical coefficients, low DC and microwave dielectric constants, and broad optical transparency ranges. The major obstacle to the development of practical polymer optoelectronic devices has been the thermal stability of the electrooptic coefficients of the guest-host polymer films. Current research has focused on finding new guest dye chromophores that possess large nonlinear optical coefficients and thermal stabilities greater than 300 degrees. We summarize our recent development of a new class of high thermal stability fused-ring chromophores, l,8-naphthoylene benzimidazoles, based on compute aided molecular design and experimental measurements of microscopic second order optical coefficients. The new chromophores were designed for their structural similarity to polyimide repeat units and consequent easy incorporation into high temperature host polyimides. They are highly colored, comparatively soluble in common organic solvents, and very stable in polyamic acid solutions. They possess relatively large second order optical coefficients and thermal stabilities exceeding 340 degrees. (MM).

Download or read book Summaries of Papers Presented at the Quantum Electronics and Laser Science Conference written by and published by . This book was released on 1989 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: