bluuebunny/crossref_metadata_2025_split huggingface dataset:
Water Soluble Polyanilines: Properties and Applications
Authors: Angelopoulos Marie , Patel Niranjan , Shaw Jane M. 
Published: March 2011

ABSTRACTA new class of water soluble conducting polyanilines have been developed. This is accomplished by oxidatively polymerizing aniline monomers on a template such as a polymeric acid. The resulting polyanilines readily dissolve in water. These Materials can be applied as removable discharge layers for electron-beam (e-beam) lithography and for SEM Mask Metrology. Cross-linkable functionality can be incorporated on the polyanilinc backbone resulting in water soluble polyanilines that are radiation curable. Upon irradiation these materials cross-link and become insoluble and thus can be utilized as permanent conducting coatings for electrostatic discharge (ESD) applications. In addition, the cross-linkable polyanilines can be made into water developable conducting resists. 1.0μm conducting lines have been patterned with e-beam irradiation.
Conducting Polymers With Chemically Sensitive Traps And Barriers: New Molecule-Based Sensors
Authors: Swager Timothy M. , Marsella Michael J. 
Published: March 2011

ABSTRACTWe present a general approach for the formation of conducting polymer based sensory materials which employ well-known Molecular recognition elements. These Methods are based upon impeding carrier transport through a conductive polymer's backbone with a barrier or by localizing a carrier with a trap. We have designed polythiophene derivatives which exhibit large changes in bandgap in the presence of specific ions. These Materials are based upon novel crown ether containing bithiophene monomers and we will discuss the details of the synthesis of the monomers and polymers. Sensory polymers which are selective for K+ and Na+ will be described. In such Materials, specific ions induce a twisting of the polymer's backbone.
Optical And Electrical Properties Of Doped Polysilanes
Authors: Kakimoto M. , Ueno H. , Kojima H. , Yamaguchi Y. , Nishimura A. 
Published: March 2011

ABSTRACTThe doping effects on optical and electrical properties of polysilanes have been investigated by in-situ Measurement. An optical absorption associated with σ–σ* transition was observed near 330 nm for polymethylphenylsilane. By iodine doping, a new absorption was observed at the longer wavelength around 420 nm, which should originate from the charge transfer between dopant and Σ-conjugated system. Similar spectral changes have also been observed for most of investigated linear polysilanes.Furthermore, we have found drastic spectral change upon iodine doping into polysilane with p-N,N-dimethyIaminophenyI substituent. It has very strong absorption up to 700 nm. It Might originate from a strong interaction between the substituent and iodine. At the same time, Σ-conjugation Might also play a significant role on doping into this system.
Descriptive Chemistry Of Self-Assembled Multilayer Second-Order NLO Materials. Chemical, Microstructural and Performance Interrelationships
Authors: Yitzchaik Shlomo , Kakkar Ashok K. , Roscoe Stephen B. , Marks Tobin J. , Lundquist Paul M. , Lin Weiping , Wong George K. 
Published: March 2011

ABSTRACTThe construction of covalently self-assembled second-order nonlinear optical (NLO) Materials containing stilbazole or alkynyl-type high-β chromophores acentrically organized on inorganic oxide substrates is discussed. These structurally different chromophores exhibit differing packing densities on the surface when introduced under the same reaction conditions. In the stilbazolium chromophores, ion-exchange of the chloride counter-anion with very large anionie organic dyes results in appreciably enhanced second harmonic generation (SHG) efficiency. The frequency-dependent SHG response for self-assembled Monolayers derived from the alkynyl-type chromophore was also investigated. The linear absorption spectra exhibit two maxima in the visible region which are assigned to electronically isolated chromophores (480 nm) and aggregated species (540 nm). The dispersion of the second-order NLO coefficient reveals that both microstructures are NLO-active. The origin of the SHG response from both assemblies is discussed.
High Temperature Electrical Conductivity Of Solution-Cast Bbl Flims.
Authors: Agrawal Ashwini K. , Wang Chyi-Shan , Song Hyun H. 
Published: March 2011

ABSTRACTThin films (18 μ thickness) of ladder polymer poly[(7-oxo-7H,10H-benz (d,e) imidazo (4′,5′:5,6) -benzimidazo (2,l-a) isoquinoline-3,4:10,ll-tetrayl)-10-carbonyl} (BBL), which were cast from an isotropie methanesulfonic acid solution of BBL, were characterized for electrical conductivity in the temperature range of 25–480 °C. The electrical conductivity was Measured in situ while the films were heated at a rate of 2 °C/Minute under vacuum. The in-plane conductivity of BBL films increased rapidly from below 10−10 S/cm at the room temperature to 5 × 10-3 S/cm at 280 °C and then increased slowly to a peak value of 5 × 10-2 S/cm at about 460 °C. The out-of-plane conductivity of the films was comparable to their in plane conductivity at temperatures below 270 °C, however, was lower by a factor of 10 than in-plane conductivity at temperatures above 270 °C. This anisotropy in conductivity of BBL films is discussed with respect to the film morphology determined by wide angle x-ray scattering studies.
Studies in The Organic Solid State
Authors: Whitesides George M. , Zerkowski Jonathan A. , MacDonald John C. , Chin Donovan 
Published: March 2011

ABSTRACTThis paper describes an approach to crystal engineering based on designing and analyzing hierarchical levels of crystalline architecture. The system under study consists of 1:1 co-crystals of melamines and barbituric acids that self-assemble into crystallographically infinite hydrogen-bonded tapes. The formation of structural elements can be rationalized and controlled using familiar molecular concepts such as steric repulsion.
Space-Charge-Limited Charge Injection From Ito/Ppv Into A Trap-Free Molecularly Doped Polymer
Authors: Antoniadis H. , Abkowitz M. , Hsieh B. R. , Jenekhe S. A. , Stolka M. 
Published: March 2011

ABSTRACTWe describe bilayer structures comprised of a poly (p-phenylene vinylene) (PPV) layer and a trap-free diaryldiamine (TPD) doped in polycarbonate (PC) layer, sandwiched between indium-tin-oxide (ITO) and aluminum (Al) contacts. Two critical phenomena in the operation of polymer based electroluminescent devices, interface injection and carrier range, are investigated. It is established that the ITO/PPV contact is capable of sustaining dark current under trap-free space-charge-limited (TFSCL) conditions into a hole transporting TPD:PC layer. TFSCL currents are not observed in devices without the PPV layer. Upon increasing the thickness of the PPV layer a deviation from the TFSCL regime is observed which is attributed to trapping of the injected holes within PPV. These observations suggest a novel method for estimating the trapping Mobility-lifetime product μτ for holes in PPV. By this means we estimate μτ ∼ 10−9 cm2/V.
Progress on Nonlinear Optical Chromophores and Polymers with Useful Nonlinearity and Thermal Stability
Authors: Twieg R. J. , Burland D. M. , Hedrick J. L. , Lee V. Y. , Miller R. D. , Moylan C. R. , Volksen W. , Walsh C. A. 
Published: March 2011

ABSTRACTOrganic nonlinear optical (NLO) polymers must possess large and stable bulk nonlinear properties if they are to be of practical use. Numerous classes of NLO chromophores and polymers have already been evaluated but the selection process, particularly as related to stability issues, has been very stochastic in nature. If suitable chromophores are to be successfully identified their thermochemical degradation Mechanisms Must be elucidated and structural modifications introduced in a rational fashion. We have devised a protocol for the evaluation of NLO chromophores which involves initial screening by thermal analysis (DSC and TGA) and selected molecular hyperpolarizability (EFISH) analysis. The Most promising candidates are incorporated into thermoplastic polymer hosts where bulk nonlinear properties (dijand rij) and additional thermal stability properties are evaluated by spectroscopie Means (UV-VIS). Cyclicvoltammetry (CV) has been identified as a useful tool for evaluation of these chromophores; in the case of azobenzenes with aliphatic amine donor and a nitro acceptor a correlation between the thermal stability and oxidation potential has been found. The Most facile thermal degradation mechanism which occurs in these dyes has been identified and structural changes to the donor group have been introduced to avert the process.
Realization Of Large, Stable Second Order Optical Nonlinearities Through Double-EndCrosslinkable Chromophores
Authors: Xu C. , Wu B. , Dalton L. R. , Shi Y. , Ranon P. M. , Kalluri S. , Steier W. H. 
Published: March 2011

ABSTRACTWe have developed a novel class of double-end crosslinkable (DEC) chromophores. Processible side-chain nonlinear optical (NLO) polymers with crosslinkable groups at the ends of chromophore pendants were synthesized from DEC Monomers. The polymers were processed into good quality films, which were subsequently poled with a corona setup and thermally cured to attain stable noncentrosymmetric order. Using this DEC approach, we have realized large optical nonlinearities (χ(2) = 90–220 pm/V) with long term stability at 125 °C.
Characterization Of Thermally Stable Dye-Doped Polyimide Based Electrooptic Materials
Authors: Meinhardt Michael B. , Cahill Paul A. , Seager Carl H. , Beuhler Allyson J. , Wargowski David A. 
Published: March 2011

ABSTRACTPreparation and characterization of novel dye-doped polyimide films for electrooptics is described. Thermal stabilities of donor-acceptor 2,5-diaryl oxazoles were evaluated by differential scanning calorimetry. Absorptive losses in thin films of Ultradel 9000D® doped with donor-acceptor oxazoles were measured by photothermal deflection spectroscopy. Absorptive losses at high doping levels may be explainable by dye-dye aggregation or dye degradation during the curing process. Lower doping levels, however, show losses of ≤ 3.0 dB/cm at 830 nm and ≤ 2.4 dB/cm at 1320 nm.
High Thermal Stability Electrooptic Chromophores And New Integrated Optical Polymer Devices
Authors: Yamada S. , Cai Y. M. , Shi R. F. , Wu M. H. , Chen W. D. , Qian Q. M. , Garito A. F. 
Published: March 2011

ABSTRACTA new class of high thermal stability fused-ring guest chromophores intended for incorporation into highly stable host polyimides has been successfully developed. Thermal stabilities far in excess of 300°C have been achieved for both the pure guest and the guest-host polyimide systems. The Microscopic second order nonlinear optical properties of the guest chromophores have been characterized both theoretically and experimentally. The achievement of the new high temperature EO chromorphores and polyimide formulations have directly resulted in the discovery of new EO device designs and architectures.
Second-Order Nonlinear Optical Polymers With Different Chromophore Arrangements
Authors: Wu Bo , Xu Chengzeng , Dalton Larry R. , Kalluri Srinath , Shi Yongqiang , Steier William H. 
Published: March 2011

ABSTRACTSecond-order nonlinear optical polymers can be divided into four groups regarding arrangements of chromophore dipoles in polymer backbones, namely, side-chain polymers, random, head-to-tail, and head-to-head Main-chain polymers. A variety of polymers with the aforementioned configurations have been designed and synthesized from functionalized amino-nitro azobenzene chromophores. Poling processes of these polymeric materials have been investigated by in-situ poling and second-harmonic generation detection.
Sol-Gel-Derived Thin Films Incorporating An Organic Second-Order NLO Compound With Large βμ
Authors: Caldwell J. B. , Cruse R. W. , Drost K. J. , Rao V. P. , Jen A. K-Y. , Wong K. Y. , Cai Y. M. , Mininni R. M. , Kenney J. , Binkley E. , Dalton L. , Shi Y. , Steier W. 
Published: March 2011

ABSTRACTWe have synthesized a new second-order NLO compound containing both the highly active tricyanovinyl electron acceptor group and appropriate funtionality for covalent bonding to an inorganic silica matrix by sol-gel processing. Sub-Micron films of this material can be prepared by spin-coating, and thicker films can be prepared by casting or by spinning multiple layers. After curing at 150 °C, these films exhibit good chemical durability. The chromophores can be aligned by either corona or parallel-plate poling during the curing process. In this paper we will discuss the synthesis of the NLO compounds; sol-gel processing and thin-film preparation; optical, thermal, and chemical properties of the films; and the results of both corona and parallel-plate poling experiments.
Optical Interconnect: Fully Embedded Etched Passive And Active Polyimide Waveguides And Devices
Authors: Fujimoto Harry H. , Das Siddhartha , Valley John F. , Stiller Marc , Dries Larry , Girton Dexter , Eck Tim Van , Ermer Susan , Binkley Ed S. , Nurse Jim C. , Kenney John T. 
Published: March 2011

ABSTRACTElectro-optic polymers are of great interest for inserting photonic elements into electronic systems. Recently Much progress has been made in both materials and processing. These polymers must have low optical loss, high mechanical integrity, low processing cost, and high temperature stability. In the first part of our talk, we present our work to produce etched single mode buried channel waveguides in an all polymide system. We have chosen polyimide because of its high temperature stability. Optical losses and waveguide characteristics are described as a function of waveguide width and index ofrefraction difference between core and cladding.Mach Zehnder Modulators fabricated using a DCM-polymide core are also described The waveguide cores are etched and fully embedded in a polyimide cladding. The active arms of the modulator are poled using parallel plate poling. The electro-optic properties of the Mach Zehnder are described operating at 830nm. Photobleached DCM waveguides are also describe. A new high temperature chromophore is presented.
Photorefractivity And Photoisomerization In Azo-Dye-Doped Polymers
Authors: Kippelen B. , Sandalphon  , Meerholz K. , Volodin B. , Lyon S. R. , Padias A. B. , Hall H. K. , Peyghambarian N. 
Published: March 2011

ABSTRACTThe photorefractive properties of photoconducting polymers doped with nonlinear azo dyes are investigated by means of polarization and field-dependent four-wave Mixing experiments. The nonlocal response of the photorefractive effect is shown by two-beam coupling experiments. High diffraction efficiencies (> 5%) and net coupling gain (6 cm-l) are demonstrated at low power with a semiconductor laser diode in 105 μm films. Under some conditions, gratings due to photoisomerization of the azo dye molecules are also present and their properties are discussed.
Phosphorus-Containing Poly (Arylene Ether)s as Second Order Nonlinear Optical Materials
Authors: Priddy Duane B. , Stacey Fu C. Y. , Pickering Timothy L. , Lackritz Hilary S. , Mcgrath James E. 
Published: March 2011

ABSTRACTPoly (arylene ether)s can be designed to be amorphous, optically clear materials with excellent hydrolytic and thermal stability as well as good electrical, Mechanical and fire resistant properties. As a result, the use of these macromolecules in second order nonlinear optical (NLO) applications are being investigated. Typically, polymeric systems with doped chromophores result in a signigicant decrease in Tg. Methods were investigated to functionalize the polymer backbone with NLO chromophores, resulting in increased Tg.
Processable Cross-Linked Polymers for Nonlinear Optical Applications
Authors: Ellen Harelstad R. , Francis Cecil V. , Leung Peter C. , Korkowski Paul F. , White Kenneth M. , Cross Elisa M. , Kitipichai Prakob 
Published: March 2011

ABSTRACTNovel difunctional barbituric acid methine dyes have been synthesized for nonlinear optical applications. These Molecules have been reacted with Multi-functional isocyanates resulting in cross-linked polyurethanes. The thermal stability of the dye in crystalline form as well as dissolved in poly (Methylmethacrylate) was studied. Results suggest that although the dye crystals were thermally stable to 300 °C, when dissolved in a polymer the stability was markedly lower.
Bipolaron Formation and Nonlinear Optical Properties in Bis-Thienyl Polyenes
Authors: Spangler C. W. , He M. Q. , Laquindanum J. , Dalton L. , Tang N. , Partanen J. , Hellwarth R. 
Published: March 2011

ABSTRACTBipolaron-like dications have been produced in both diphenyl and bis-thienyl polyenes by oxidative doping in solution. However, until now spectroscopie studies of the charge state generation beyond the hexaene have been precluded due to lack of solubility and processibility. We have now been able to extend these studies to the decaene by incorporating solubilizing substituents on the thienyl end caps. For the neutral species, degenerate four wave Mixing (DFWM) studies indicate that χ(3) is still increasing as a function of conjugation length. Introduction of mesomerically interactive RS groups on the thiophene rings further increases both solubility and optical nonlinearity.
Liquid Crystalline Polymers In Nematic Solvents
Authors: Williams D.R.M. , Halperin A. 
Published: March 2011

ABSTRACTWe present a theoretical study of liquid crystalline polymers in nematic solvents. We focus on the following topics: (i) Rod-like chains confined between plates, (ii) Flexible chains in a slit (iii) Nematic brushes and double-brushes (iv) Anchoring transitions. Confined and grafted chains in nematic solvents can exhibit a variety of interesting effects, including quasi-piezoelectricity and a lowering of the critical voltage for the Fréedericksz transition.
Characterization Of Physically Vapor Deposited Af2400 Thin Films
Authors: Chow R. , Spragge M. K. , Loomis G. E. , Rainer F. , Ward R. L. , Thomas I. M. , Kozlowski M. R. 
Published: March 2011

ABSTRACTAnti-reflective optical coatings made with Teflon AF2400 had the highest laser damage thresholds recorded for physical vapor deposited coatings at the Lawrence Livermore National Laboratory damage facility. Physical vapor deposited layers of Teflon AF2400, a perfluorinated amorphous polymer, Maintained the bulk optical properties of a high transmittance from 200 nm to 1200 nm, and a low refractive index. In addition, the refractive index can be intentionally reduced by control of two common deposition parameters, deposition rate and substrate temperature. Scanning electron microscopy and nuclear magnetic resonance observations indicated that morphological changes caused the variations in the refractive index rather than compositional changes. The coatings adhered to fused silica and silicon wafers under normal laboratory handling conditions.
Energy Transfer And Emission Processes In Sol-Gel Materials Doped With Europium (III) Complexes
Authors: Wang Xiao-Jun , Matthews Lowell R. , Knobbet E. T. 
Published: March 2011

ABSTRACTOptical emission behavior in sol-gel-derived Materials doped with tris (4,4,4-trifluoro-l- (2′-thienyl) -l,3-butanedionato-O,O′)europium (III), Eu (ttfa)3, has been investigated by exciting the electronic levels of both europium (III) and the β-diketonate ligand (ttfa-). Energy transfer processes between the ttfa− ligands and europium (III) have been studied by time-resolved luminescence spectroscopy. The dynamic processes were compared in three sol-gel-derived host Matrices (silica, an acrylate ORMOSIL, and an epoxide ORMOSIL). Concentration dependence of the energy transfer rates was also studied.
Even Parity States in Ppv, Polythiophene and Polysilanes
Authors: Guo F. , Chandross M. , Mazumdar S. 
Published: March 2011

ABSTRACTTwo photon absorptions (TPA) in conjugated polymers with large bond alternation are reinterpreted. TPA to the 2Ag in long chains should be tiny due to cancellation effects, and therefore the observed strong, narrow TPA is to a higher even parity state. We also present the first theoretical evidence for bound biexcitons, and explain recent photoinduced absorption data.
Langmuir-Blodgett Film Waveguide with The Nonlinearity Inversion in The Thickness Direction
Authors: Asai Nobutoshi , Fujiwara Ichiro , Tamada Hitoshi , Seto Jun'etsu 
Published: March 2011

ABSTRACTA second order nonlinear optical susceptibility inversion structure in the thickness direction (NIST) is proposed for enhancing the efficiency of Cerenkov radiation type phase matched second harmonic generation (CRPM-SHG). With the aid of the coupled-mode theory, it is analyzed that the efficiency is enhanced by 50 to 100 times by introducing the NIST structure to a waveguiding layer made of a 2-docosylamino-5-nitropyridine (DCANP) Langmuir-Blodgett (LB) film, and that the optical conditions for the most efficient CRPM-SHG are equivalent to those for guided mode SHG at the cutoff points of the modes. Several fabrication methods are possible for NIST waveguides. For the first time, a NIST waveguide has been fabricated using a DCANP-LB film by employing a novel and simple technique in which the substrate inversion is carried out during the dipping process. The inversion in nonlinearity was confirmed using the maker fringe method and polarized absorption spectra. A NIST planar waveguide of 260 Monolayers of DCANP (570 nm thick) was fabricated. Intense CRPM-SHG was observed from the waveguide when a YAG laser was coupled into it. The intensity was 20 to 30 times larger than that of a conventional waveguide of the same thickness.
Influence of Crystalline Structure on Performance of Thin Film Transistors
Authors: Celler G. K. , Ng K. K. , Trimble L. E. , Povilonis E. I. 
Published: March 2011

ABSTRACTWe have developed a procedure to optimize electron mobility and leakage currents in MOSFETs fabricated in laser recrystallized polysilicon films on SiO2. A shaped laser beam was used to obtain grain boundaries aligned with the current flow in MOS transistors. To suppress grain boundary diffusion, rapid thermal annealing replaced all high temperature processing steps subsequent to source and drain implantation. By combining these two approaches, functional transistors as short as 1.5 μm were obtained, and also 2 μm-channel 19-stage ring oscillators with 115 psec/stage propagation delay.
Electrical Characterization of Laser/Energy-Beam Recrystallized Thin Film Silicon-On-Insulator (SOI)
Authors: Lee El-Hang , Ruprecht D. J. 
Published: March 2011

ABSTRACTSpreading resistance has been measured for various types of grain boundaries formed on graphite heater recrystallized SOI samples (G-SOI) or laser strip beam-recrystallized SOI samples (L-SOI) in order to identify the characteristic relation between the morphological/structural variation of the boundary defects and their electrical transport properties. In general, the resistance values across L-SOI sub-boundaries are higher than those across G-SOI sub-boundaries. TEM analyses reveal evidences of higher degree of crystallographic mismatch (up to 10°) in L-SOI sub-boundaries than that (1 – 2°) in G-SOI sub-boundaries. The measurement also revealed the evidences of counter-doping near the seed areas where the epitaxial growth initiated.