National Library of Energy BETA

Sample records for defects charge transport

  1. Hovering Black Holes from Charged Defects

    E-Print Network [OSTI]

    Gary T. Horowitz; Nabil Iqbal; Jorge E. Santos; Benson Way

    2015-05-05

    We construct the holographic dual of an electrically charged, localised defect in a conformal field theory at strong coupling, by applying a spatially dependent chemical potential. We find that the IR behaviour of the spacetime depends on the spatial falloff of the potential. Moreover, for sufficiently localized defects with large amplitude, we find that a new gravitational phenomenon occurs: a spherical extremal charged black hole nucleates in the bulk: a hovering black hole. This is a second order quantum phase transition. We construct this new phase with several profiles for the chemical potential and study its properties. We find an apparently universal behaviour for the entropy of the defect as a function of its amplitude. We comment on the possible field theory implications of our results.

  2. Transport on a Lattice with Dynamical Defects

    E-Print Network [OSTI]

    Francesco Turci; Andrea Parmeggiani; Estelle Pitard; M. Carmen Romano; Luca Ciandrini

    2013-01-10

    Many transport processes in nature take place on substrates, often considered as unidimensional lanes. These unidimensional substrates are typically non-static: affected by a fluctuating environment, they can undergo conformational changes. This is particularly true in biological cells, where the state of the substrate is often coupled to the active motion of macromolecular complexes, such as motor proteins on microtubules or ribosomes on mRNAs, causing new interesting phenomena. Inspired by biological processes such as protein synthesis by ribosomes and motor protein transport, we introduce the concept of localized dynamical sites coupled to a driven lattice gas dynamics. We investigate the phenomenology of transport in the presence of dynamical defects and find a novel regime characterized by an intermittent current and subject to severe finite-size effects. Our results demonstrate the impact of the regulatory role of the dynamical defects in transport, not only in biology but also in more general contexts.

  3. Morphology and Charge Transport in Conjugated Polymers

    E-Print Network [OSTI]

    McGehee, Michael

    Morphology and Charge Transport in Conjugated Polymers R. J. KLINE AND M. D. McGEHEE Department charge transport and morphology is key to increasing the charge carrier mobility of conjugated polymers to provide insight into how the charge carriers move through a conjugated polymer film and provide a model

  4. Transport by molecular motors in the presence of static defects

    E-Print Network [OSTI]

    Yan Chai; Reinhard Lipowsky; Stefan Klumpp

    2009-05-07

    The transport by molecular motors along cytoskeletal filaments is studied theoretically in the presence of static defects. The movements of single motors are described as biased random walks along the filament as well as binding to and unbinding from the filament. Three basic types of defects are distinguished, which differ from normal filament sites only in one of the motors' transition probabilities. Both stepping defects with a reduced probability for forward steps and unbinding defects with an increased probability for motor unbinding strongly reduce the velocities and the run lengths of the motors with increasing defect density. For transport by single motors, binding defects with a reduced probability for motor binding have a relatively small effect on the transport properties. For cargo transport by motors teams, binding defects also change the effective unbinding rate of the cargo particles and are expected to have a stronger effect.

  5. Transport-reaction model for defect and carrier behavior within displacement cascades in gallium arsenide

    SciTech Connect (OSTI)

    Wampler, William R.; Myers, Samuel M.

    2014-02-01

    A model is presented for recombination of charge carriers at displacement damage in gallium arsenide, which includes clustering of the defects in atomic displacement cascades produced by neutron or ion irradiation. The carrier recombination model is based on an atomistic description of capture and emission of carriers by the defects with time evolution resulting from the migration and reaction of the defects. The physics and equations on which the model is based are presented, along with details of the numerical methods used for their solution. The model uses a continuum description of diffusion, field-drift and reaction of carriers and defects within a representative spherically symmetric cluster. The initial radial defect profiles within the cluster were chosen through pair-correlation-function analysis of the spatial distribution of defects obtained from the binary-collision code MARLOWE, using recoil energies for fission neutrons. Charging of the defects can produce high electric fields within the cluster which may influence transport and reaction of carriers and defects, and which may enhance carrier recombination through band-to-trap tunneling. Properties of the defects are discussed and values for their parameters are given, many of which were obtained from density functional theory. The model provides a basis for predicting the transient response of III-V heterojunction bipolar transistors to pulsed neutron irradiation.

  6. Influence of Topological Spin Fluctuations on Charge Transport

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Influence of Topological Spin Fluctuations on Charge Transport Influence of Topological Spin Fluctuations on Charge Transport Print Wednesday, 27 April 2005 00:00 Layered...

  7. Hopping charge transport in organic materials

    E-Print Network [OSTI]

    Novikov, S V

    2013-01-01

    General properties of the transport of charge carriers (electrons and holes) in disordered organic materials are discussed. It was demonstrated that the dominant part of the total energetic disorder in organic material is usually provided by the electrostatic disorder, generated by randomly located and oriented dipoles and quadrupoles. For this reason this disorder is strongly spatially correlated. Spatial correlation directly governs the field dependence of the carrier drift mobility. Shape of the current transients, which is of primary importance for a correct determination of the carrier mobility, is considered. A notable feature of the electrostatic disorder is its modification in the vicinity of the electrode, and this modification takes place without modification of the structure of the material. It is shown how this phenomenon affects characteristics of the charge injection. We consider also effect of inter-charge interaction on charge transport.

  8. Charge Transport Across Insulating Self-Assembled Mono layers...

    Office of Scientific and Technical Information (OSTI)

    Country of Publication: United States Language: English Subject: catalysis (homogeneous), solar (photovoltaic), bio-inspired, charge transport, mesostructured materials, materials...

  9. Nanoscale Charge Transport in Excitonic Solar Cells

    SciTech Connect (OSTI)

    Venkat Bommisetty, South Dakota State University

    2011-06-23

    Excitonic solar cells, including all-organic, hybrid organic-inorganic and dye-sensitized solar cells (DSSCs), offer strong potential for inexpensive and large-area solar energy conversion. Unlike traditional inorganic semiconductor solar cells, where all the charge generation and collection processes are well understood, these excitonic solar cells contain extremely disordered structures with complex interfaces which results in large variations in nanoscale electronic properties and has a strong influence on carrier generation, transport, dissociation and collection. Detailed understanding of these processes is important for fabrication of highly efficient solar cells. Efforts to improve efficiency are underway at a large number of research groups throughout the world focused on inorganic and organic semiconductors, photonics, photophysics, charge transport, nanoscience, ultrafast spectroscopy, photonics, semiconductor processing, device physics, device structures, interface structure etc. Rapid progress in this multidisciplinary area requires strong synergetic efforts among researchers from diverse backgrounds. Such effort can lead to novel methods for development of new materials with improved photon harvesting and interfacial treatments for improved carrier transport, process optimization to yield ordered nanoscale morphologies with well defined electronic structures.

  10. Surface-induced charge state conversion of nitrogen-vacancy defects in nanodiamonds

    E-Print Network [OSTI]

    L. Rondin; G. Dantelle; A. Slablab; F. Grosshans; F. Treussart; P. Bergonzo; S. Perruchas; T. Gacoin; M. Chaigneau; H. -C. Chang; V. Jacques; J. -F. Roch

    2010-10-19

    We present a study of the charge state conversion of single nitrogen-vacancy (NV) defects hosted in nanodiamonds (NDs). We first show that the proportion of negatively-charged NV$^{-}$ defects, with respect to its neutral counterpart NV$^{0}$, decreases with the size of the ND. We then propose a simple model based on a layer of electron traps located at the ND surface which is in good agreement with the recorded statistics. By using thermal oxidation to remove the shell of amorphous carbon around the NDs, we demonstrate a significant increase of the proportion of NV$^{-}$ defects in 10-nm NDs. These results are invaluable for further understanding, control and use of the unique properties of negatively-charged NV defects in diamond

  11. Influence of Topological Spin Fluctuations on Charge Transport

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Influence of Topological Spin Fluctuations on Charge Transport Print Layered transition metal oxides are the focus of intense research efforts because they might clarify the...

  12. Surface-induced charge state conversion of nitrogen-vacancy defects in nanodiamonds

    E-Print Network [OSTI]

    Rondin, L; Slablab, A; Treussart, F; Bergonzo, P; Perruchas, S; Gacoin, T; Chaigneau, M; Chang, H -C; Jacques, V; Roch, J -F

    2010-01-01

    We present a study of the charge state conversion of single nitrogen-vacancy (NV) defects hosted in nanodiamonds whose size ranges from 10 nm to 100 nm. We first show that after irradiation and annealing of the nanodiamond powder, the proportion of negatively-charged NV- defects, with respect to its neutral counterpart NV0, decreases with the size of the nanoparticle. We propose a simple model based on a layer of electron traps located at the nanodiamond surface which is in good agreement with the statistics we recorded. By using thermal oxidation to remove the shell of amorphous carbon around the nanodiamonds, we achieve a significant increase of the proportion of NV- defects in approximately 10-nm nanodiamonds. These results demonstrate the importance of controlling the nanodiamond surface for the development of the numerous applications of NV centers which are made possible by their unique photostability and spin properties.

  13. Transport in charged colloids driven by thermoelectricity Alois Wrger

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Transport in charged colloids driven by thermoelectricity Alois Würger CPMOH, Université Bordeaux 1 to a strong increase with temperature. The di¤erence of the heat of transport of co-ions and counterions gives rise to a thermoelectric ...eld that drives the colloid to the cold or to the warm, depending

  14. Multiscale Defect Formation and Transport in Materials in Extreme Environments

    E-Print Network [OSTI]

    Seif, Dariush

    2013-01-01

    material symmetry (Iso, Anis) in the defect dipole tensors (through the [110]: Iso. P , Iso. ? (a) [110]: Anis. P ,Iso. ? [110]: Anis. P (1) , Anis. ? [100]: Iso. P , Iso. ? (

  15. Revealing origin of quasi-one dimensional current transport in defect rich two dimensional materials

    SciTech Connect (OSTI)

    Lotz, Mikkel R.; Boll, Mads; Bggild, Peter; Petersen, Dirch H., E-mail: dirch.petersen@nanotech.dtu.dk [Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, DTU Nanotech Building 345 East, DK-2800 Kgs. Lyngby (Denmark); Hansen, Ole [Department of Micro- and Nanotechnology, Technical University of Denmark, DTU Nanotech Building 345 East, DK-2800 Kgs. Lyngby (Denmark); Danish National Research Foundation's Center for Individual Nanoparticle Functionality (CINF), Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); Kjr, Daniel [Department of Micro- and Nanotechnology, Technical University of Denmark, DTU Nanotech Building 345 East, DK-2800 Kgs. Lyngby (Denmark); CAPRES A/S, Scion-DTU, Building 373, DK-2800 Kgs. Lyngby (Denmark)

    2014-08-04

    The presence of defects in graphene have for a long time been recognized as a bottleneck for its utilization in electronic and mechanical devices. We recently showed that micro four-point probes may be used to evaluate if a graphene film is truly 2D or if defects in proximity of the probe will lead to a non-uniform current flow characteristic of lower dimensionality. In this work, simulations based on a finite element method together with a Monte Carlo approach are used to establish the transition from 2D to quasi-1D current transport, when applying a micro four-point probe to measure on 2D conductors with an increasing amount of line-shaped defects. Clear 2D and 1D signatures are observed at low and high defect densities, respectively, and current density plots reveal the presence of current channels or branches in defect configurations yielding 1D current transport. A strong correlation is found between the density filling factor and the simulation yield, the fraction of cases with 1D transport and the mean sheet conductance. The upper transition limit is shown to agree with the percolation threshold for sticks. Finally, the conductance of a square sample evaluated with macroscopic edge contacts is compared to the micro four-point probe conductance measurements and we find that the micro four-point probe tends to measure a slightly higher conductance in samples containing defects.

  16. Intracellular transport driven by cytoskeletal motors: General mechanisms and defects

    E-Print Network [OSTI]

    Cecile Appert-Rolland; Maximilian Ebbinghaus; Ludger Santen

    2015-07-22

    Cells are strongly out-of-equilibrium systems driven by continuous energy supply. They carry out many vital functions requiring active transport of various ingredients and organelles, some being small, others being large. The cytoskeleton, composed of three types of filaments, determines the shape of the cell and plays a role in cell motion. It also serves as a road network for the so-called cytoskeletal motors. These molecules can attach to a cytoskeletal filament, perform directed motion, possibly carrying along some cargo, and then detach. It is a central issue to understand how intracellular transport driven by molecular motors is regulated, in particular because its breakdown is one of the signatures of some neuronal diseases like the Alzheimer. We give a survey of the current knowledge on microtubule based intracellular transport. We first review some biological facts obtained from experiments, and present some modeling attempts based on cellular automata. We start with background knowledge on the original and variants of the TASEP (Totally Asymmetric Simple Exclusion Process), before turning to more application oriented models. After addressing microtubule based transport in general, with a focus on in vitro experiments, and on cooperative effects in the transportation of large cargos by multiple motors, we concentrate on axonal transport, because of its relevance for neuronal diseases. It is a challenge to understand how this transport is organized, given that it takes place in a confined environment and that several types of motors moving in opposite directions are involved. We review several features that could contribute to the efficiency of this transport, including the role of motor-motor interactions and of the dynamics of the underlying microtubule network. Finally, we discuss some still open questions.

  17. Intracellular transport driven by cytoskeletal motors: General mechanisms and defects

    E-Print Network [OSTI]

    Appert-Rolland, Cecile; Santen, Ludger

    2015-01-01

    Cells are strongly out-of-equilibrium systems driven by continuous energy supply. They carry out many vital functions requiring active transport of various ingredients and organelles, some being small, others being large. The cytoskeleton, composed of three types of filaments, determines the shape of the cell and plays a role in cell motion. It also serves as a road network for the so-called cytoskeletal motors. These molecules can attach to a cytoskeletal filament, perform directed motion, possibly carrying along some cargo, and then detach. It is a central issue to understand how intracellular transport driven by molecular motors is regulated, in particular because its breakdown is one of the signatures of some neuronal diseases like the Alzheimer. We give a survey of the current knowledge on microtubule based intracellular transport. We first review some biological facts obtained from experiments, and present some modeling attempts based on cellular automata. We start with background knowledge on the origi...

  18. Ambipolar charge transport in microcrystalline silicon thin-film transistors

    SciTech Connect (OSTI)

    Knipp, Dietmar; Marinkovic, M.; Chan, Kah-Yoong; Gordijn, Aad; Stiebig, Helmut

    2011-01-15

    Hydrogenated microcrystalline silicon ({mu}c-Si:H) is a promising candidate for thin-film transistors (TFTs) in large-area electronics due to high electron and hole charge carrier mobilities. We report on ambipolar TFTs based on {mu}c-Si:H prepared by plasma-enhanced chemical vapor deposition at temperatures compatible with flexible substrates. Electrons and holes are directly injected into the {mu}c-Si:H channel via chromium drain and source contacts. The TFTs exhibit electron and hole charge carrier mobilities of 30-50 cm{sup 2}/V s and 10-15 cm{sup 2}/V s, respectively. In this work, the electrical characteristics of the ambipolar {mu}c-Si:H TFTs are described by a simple analytical model that takes the ambipolar charge transport into account. The analytical expressions are used to model the transfer curves, the potential and the net surface charge along the channel of the TFTs. The electrical model provides insights into the electronic transport of ambipolar {mu}c-Si:H TFTs.

  19. Phase Fluctuations and the Absence of Topological Defects in Photo-excited Charge Ordered Nickelate

    SciTech Connect (OSTI)

    Lee, W.S.; Chuang, Y.D.; Moore, R.G.; Zhu, Y.; Patthey, L.; Trigo, M.; Lu, D.H.; Kirchmann, P.S.; Krupin, O.; Yi, M.; Langner, M.; Huse, N.; Robinson, J.S.; Chen, Y.; Zhou, S.Y.; Coslovich, G.; Huber, B.; Reis, D.A.; Kaindl, R.A.; Schoenlein, R.W.; Doering, D.

    2012-05-15

    The dynamics of an order parameter's amplitude and phase determines the collective behaviour of novel states emerging in complex materials. Time- and momentum-resolved pump-probe spectroscopy, by virtue of measuring material properties at atomic and electronic time scales out of equilibrium, can decouple entangled degrees of freedom by visualizing their corresponding dynamics in the time domain. Here we combine time-resolved femotosecond optical and resonant X-ray diffraction measurements on charge ordered La{sub 1.75}Sr{sub 0.25}NiO{sub 4} to reveal unforeseen photoinduced phase fluctuations of the charge order parameter. Such fluctuations preserve long-range order without creating topological defects, distinct from thermal phase fluctuations near the critical temperature in equilibrium. Importantly, relaxation of the phase fluctuations is found to be an order of magnitude slower than that of the order parameter's amplitude fluctuations, and thus limits charge order recovery. This new aspect of phase fluctuations provides a more holistic view of the phase's importance in ordering phenomena of quantum matter.

  20. Phase fluctuations and the absence of topological defects in photo-excited charge ordered nickelate

    SciTech Connect (OSTI)

    Lee, W.S.; Chuang, Y.D.; Moore, R.G.; Zhu, Y.; Patthey, L.; Trigo, M.; Lu, D.H.; Kirchmann, P.S.; Krupin, O.; Yi, M.; Langner, M.; Huse, N.; Robinson, J.S.; Chen, Y.; Zhou, S.Y.; Coslovich, G.; Huber, B.; Reis, D.A.; Kaindl, R.A.; Schoenlein, R.W.; Doering, D.; Denes, P.; Schlotter, W.F.; Turner, J.J.; Johnson, S.L.; Fö rst, M.; Sasagawa, T.; Kung, Y.F.; Sorini, A.P.; Kemper, A.F.; Moritz, B.; Devereaux, T.P.; Lee, D.-H.; Shen, Z.X.; Hussain, Z.

    2012-01-01

    The dynamics of an order parameter's amplitude and phase determines the collective behaviour of novel states emerging in complex materials. Time- and momentum-resolved pump-probe spectroscopy, by virtue of measuring material properties at atomic and electronic time scales out of equilibrium, can decouple entangled degrees of freedom by visualizing their corresponding dynamics in the time domain. Here we combine time-resolved femotosecond optical and resonant X-ray diffraction measurements on charge ordered La1.75Sr0.25NiO4 to reveal unforeseen photoinduced phase fluctuations of the charge order parameter. Such fluctuations preserve long-range order without creating topological defects, distinct from thermal phase fluctuations near the critical temperature in equilibrium. Importantly, relaxation of the phase fluctuations is found to be an order of magnitude slower than that of the order parameter's amplitude fluctuations, and thus limits charge order recovery. This new aspect of phase fluctuations provides a more holistic view of the phase's importance in ordering phenomena of quantum matter.

  1. Mass Transport Investigated with the Electrochemical and Electrogravimetric Impedance Techniques. 3. Complex Charge Transport in PPy/PSS Films

    E-Print Network [OSTI]

    Kwak, Juhyoun

    Mass Transport Investigated with the Electrochemical and Electrogravimetric Impedance Techniques. 3. Complex Charge Transport in PPy/PSS Films Haesik Yang and Juhyoun Kwak* Department of Chemistry, Korea AdVember 24, 1997 For the first time, the complex charge transport mechanism for polypyrrole

  2. Charge Transport and Glassy Dynamics in Ionic Liquids

    SciTech Connect (OSTI)

    Sangoro, Joshua R; Kremer, Friedrich

    2012-01-01

    Ionic liquids (ILs) exhibit unique features such as low melting points, low vapor pressures, wide liquidus temperature ranges, high thermal stability, high ionic conductivity, and wide electrochemical windows. As a result, they show promise for use in variety of applications: as reaction media, in batteries and supercapacitors, in solar and fuel cells, for electrochemical deposition of metals and semiconductors, for protein extraction and crystallization, and many others. Because of the ease with which they can be supercooled, ionic liquids offer new opportunities to investigate long-standing questions regarding the nature of the dynamic glass transition and its possible link to charge transport. Despite the significant steps achieved from experimental and theoretical studies, no generally accepted quantitative theory of dynamic glass transition to date has been capable of reproducing all the experimentally observed features. In this Account, we discuss recent studies of the interplay between charge transport and glassy dynamics in ionic liquids as investigated by a combination of several experimental techniques including broadband dielectric spectroscopy, pulsed field gradient nuclear magnetic resonance, dynamic mechanical spectroscopy, and differential scanning calorimetry. Based on EinsteinSmoluchowski relations, we use dielectric spectra of ionic liquids to determine diffusion coefficients in quantitative agreement with independent pulsed field gradient nuclear magnetic resonance measurements, but spanning a broader range of more than 10 orders of magnitude. This approach provides a novel opportunity to determine the electrical mobility and effective number density of charge carriers as well as their types of thermal activation from the measured dc conductivity separately. We also unravel the origin of the remarkable universality of charge transport in different classes of glass-forming ionic liquids.

  3. Defect Interactions and Ionic Transport in Scandia Stabilized Zirconia

    SciTech Connect (OSTI)

    Devanathan, Ramaswami; Thevuthasan, Suntharampillai; Gale, Julian D.

    2009-06-24

    Atomistic simulation has been used to study ionic transport in scandia-stabilized zirconia, as well as scandia and yttria-co-doped zirconia, as a function of temperature and composition. The oxygen diffusion coefficient shows a peak at a composition of 6 mole % Sc2O3. Oxygen vacancies prefer to be second nearest neighbours to yttrium ions, but have little preference between first and second neighbour positions with respect to scandium ions. The Sc-O bond length is about 2.17 compared to 2.28 for the Y-O bond. Oxygen migration between cation tetrahedra is impeded less effectively by Sc-Sc edges than by Y-Y edges. A neutral cluster of two scandium ions with an oxygen vacancy in the common first neighbour position has a binding energy of -0.56 eV. The formation of such clusters may contribute to conductivity degradation of stabilized zirconia at elevated temperature.

  4. Introducing thermally stable inter-tube defects to assist off-axial phonon transport in carbon nanotube films

    SciTech Connect (OSTI)

    Wang, Jing [Department of Materials Science and Engineering, Texas A and M University, College Station, Texas 77843 (United States); Chen, Di; Wallace, Joseph; Gigax, Jonathan; Wang, Xuemei [Department of Nuclear Engineering, Texas A and M University, College Station, Texas, 77843 (United States); Shao, Lin, E-mail: lshao@tamu.edu [Department of Materials Science and Engineering, Texas A and M University, College Station, Texas 77843 (United States); Department of Nuclear Engineering, Texas A and M University, College Station, Texas, 77843 (United States)

    2014-05-12

    Through integrated molecular dynamics (MD) simulations and experimental studies, we demonstrated the feasibility of an ion-irradiation-and-annealing based phonon engineering technique to enhance thermal conductivity of carbon nanotube (CNT) films. Upon ion irradiation of CNT films, both inter-tube defects and intra-tube defects are introduced. Our MD simulations show that inter-tube defects created between neighboring tubes are much more stable than intra-tube defects created on tube graphitic planes. Upon thermal annealing, intra-tube defects are preferentially removed but inter-tube defects stay. Consequently, axial phonon transport increases due to reduced phonon scattering and off-axial phonon transport is sustained due to the high stability of inter-tube defects, leading to a conductivity enhancement upon annealing. The modeling predictions agree with experimental observations that thermal conductivities of CNT films were enhanced after 2?MeV hydrogen ion irradiations and conductivities were further enhanced upon post irradiation annealing.

  5. Transport properties in bilayer Quantum Hall systems in the presence of a topological defect

    E-Print Network [OSTI]

    Gerardo Cristofano; Vincenzo Marotta; Adele Naddeo; Giuliano Niccoli

    2006-06-27

    Following a suggestion given in Phys. Lett. B 571(2003) 621, we show how a bilayer Quantum Hall system at fillings nu =1/p+1 can exhibit a point-like topological defect in its edge state structure. Indeed our CFT theory for such a system, the Twisted Model (TM), gives rise in a natural way to such a feature in the twisted sector. Our results are in agreement with recent experimental findings (Phys. Rev. B 72 (2005) 041305) which evidence the presence of a topological defect in the transport properties of the bilayer system.

  6. Local charge transport properties of hydrazine reduced monolayer graphene oxide sheets prepared under pressure condition

    SciTech Connect (OSTI)

    Ryuzaki, Sou, E-mail: ryuzaki.soh.341@m.kyushu-u.ac.jp; Meyer, Jakob A. S.; Petersen, Sren; Nrgaard, Kasper; Hassenkam, Tue; Laursen, Bo W. [Nano-Science Center and Department of Chemistry, University of Copenhagen, Universitetparken 5, 2100 Kbenhaven (Denmark)

    2014-09-01

    Charge transport properties of chemically reduced graphene oxide (RGO) sheets prepared by treatment with hydrazine were examined using conductive atomic force microscopy. The current-voltage (I-V) characteristics of monolayer RGO sheets prepared under atmospheric pressure followed an exponentially increase due to 2D variable-range hopping conduction through small graphene domains in an RGO sheet containing defect regions of residual sp{sup 3} carbon clusters bonded to oxygen groups, whereas RGO sheets prepared in a closed container under moderate pressure showed linear I-V characteristics with a conductivity of 267.2?537.5?S/m. It was found that the chemical reduction under pressure results in larger graphene domains (sp{sup 2} networks) in the RGO sheets when compared to that prepared under atmospheric pressure, indicating that the present reduction of GO sheets under the pressure is one of the effective methods to make well-reduced GO sheets.

  7. Charge and Spin Transport in Dilute Magnetic Semiconductors

    SciTech Connect (OSTI)

    Ullrich, Carsten A.

    2009-07-23

    This proposal to the DOE outlines a three-year plan of research in theoretical and computational condensed-matter physics, with the aim of developing a microscopic theory for charge and spin dynamics in disordered materials with magnetic impurities. Important representatives of this class of materials are the dilute magnetic semiconductors (DMS), which have attracted great attention as a promising basis for spintronics devices. There is an intense experimental effort underway to study the transport properties of ferromagnetic DMS such as (Ga,Mn)As, and a number of interesting features have emerged: negative magnetoresistance, anomalous Hall effect, non-Drude dynamical conductivity, and resistivity maxima at the Curie temperature. Available theories have been able to account for some of these features, but at present we are still far away from a systematic microscopic understanding of transport in DMS. We propose to address this challenge by developing a theory of charge and spin dynamics based on a combination of the memory-function formalism and time-dependent density functional theory. This approach will be capable of dealing with two important issues: (a) the strong degree of correlated disorder in DMS, close to the localization transition (which invalidates the usual relaxation-time approximation to the Boltzmann equation), (b) the essentially unknown role of dynamical many-body effects such as spin Coulomb drag. We will calculate static and dynamical conductivities in DMS as functions of magnetic order and carrier density, which will advance our understanding of recent transport and infrared absorption measurements. Furthermore, we will study collective plasmon excitations in DMS (3D, 2D and quantum wells), whose linewidths could constitute a new experimental probe of the correlation of disorder, many-body effects and charge and spin dynamics in these materials.

  8. Light-Induced Charge Transport within a Single Asymmetric Nanowire

    SciTech Connect (OSTI)

    Liu, Chong [Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Hwang, Yun Yeong [Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Jeong, Hoon Eui [Univ. of California, Berkeley, CA (United States); Yang, Peidong [Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)

    2011-01-21

    Artificial photosynthetic systems using semiconductor materials have been explored for more than three decades in order to store solar energy in chemical fuels such as hydrogen. By mimicking biological photosynthesis with two light-absorbing centers that relay excited electrons in a nanoscopic space, a dual-band gap photoelectrochemical (PEC) system is expected to have higher theoretical energy conversion efficiency than a single band gap system. This work demonstrates the vectorial charge transport of photo-generated electrons and holes within a single asymmetric Si/TiO2 nanowire using Kelvin probe force microscopy (KPFM). Under UV illumination, higher surface potential was observed on the n-TiO? side, relative to the potential of the p-Si side, as a result of majority carriers recombination at the Si/TiO? interface. These results demonstrate a new approach to investigate charge separation and transport in a PEC system. This asymmetric nanowire heterostructure, with a dual band gap configuration and simultaneously exposed anode and cathode surfaces represents an ideal platform for the development of technologies for the generation of solar fuels, although better photoanode materials remain to be discovered.

  9. Charge Transport in one Dimension:Dissipative and Non-Dissipative Space-Charge Limited Currents

    E-Print Network [OSTI]

    S. R. Holcombe; E. R. Smith

    2012-04-06

    We consider charge transport in nanopores where the dielectric constant inside the nanopore is much greater than in the surrounding material, so that the flux of the electric fields due to the charges is almost entirely confined to the nanopore. That means that we may model the electric fields due to charge densities in the nanopore in terms of average properties across the nanopore as solutions of one dimensional Poisson equations. We develop basic equations for an M component system using equations of continuity to relate concentrations to currents, and flux equations relating currents to concentration gradients and conductivities. We then derive simplified scaled versions of the equations. We develop exact solutions for the one component case in a variety of boundary conditions using a Hopf-Cole transformation, Fourier series, and periodic solutions of the Burgers equation. These are compared with a simpler model in which the scaled diffusivity is zero so that all charge motion is driven by the electric field. In this non-dissipative case, recourse to an admissibility condition is utilised to obtain the physically relevant weak solution of a Riemann problem concerning the electric field. It is shown that the admissibility condition is Poynting's theorem.

  10. Charge carrier transport properties in layer structured hexagonal boron nitride

    SciTech Connect (OSTI)

    Doan, T. C.; Li, J.; Lin, J. Y.; Jiang, H. X., E-mail: hx.jiang@ttu.edu [Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, Texas 79409 (United States)

    2014-10-15

    Due to its large in-plane thermal conductivity, high temperature and chemical stability, large energy band gap (~ 6.4 eV), hexagonal boron nitride (hBN) has emerged as an important material for applications in deep ultraviolet photonic devices. Among the members of the III-nitride material system, hBN is the least studied and understood. The study of the electrical transport properties of hBN is of utmost importance with a view to realizing practical device applications. Wafer-scale hBN epilayers have been successfully synthesized by metal organic chemical deposition and their electrical transport properties have been probed by variable temperature Hall effect measurements. The results demonstrate that undoped hBN is a semiconductor exhibiting weak p-type at high temperatures (> 700?K). The measured acceptor energy level is about 0.68 eV above the valence band. In contrast to the electrical transport properties of traditional III-nitride wide bandgap semiconductors, the temperature dependence of the hole mobility in hBN can be described by the form of ? ? (T/T{sub 0}){sup ??} with ? = 3.02, satisfying the two-dimensional (2D) carrier transport limit dominated by the polar optical phonon scattering. This behavior is a direct consequence of the fact that hBN is a layer structured material. The optical phonon energy deduced from the temperature dependence of the hole mobility is ?? = 192 meV (or 1546 cm{sup -1}), which is consistent with values previously obtained using other techniques. The present results extend our understanding of the charge carrier transport properties beyond the traditional III-nitride semiconductors.

  11. Charge transport in nanopatterned PbS colloidal quantum dot arrays

    E-Print Network [OSTI]

    Ray, Nirat

    2015-01-01

    In this thesis, we study charge transport in nanopatterned arrays of PbS colloidal quantum dots using conventional two-probe measurements and an integrated charge sensor. PbS dots are synthesized in solution with an organic ...

  12. Low-temperature charge transport in Ga-acceptor nanowires implanted by focused-ion beams

    E-Print Network [OSTI]

    Robinson, SJ

    2008-01-01

    Low-Temperature Charge Transport in Ga-Acceptor Nanowiresare highly nonlinear at low temperatures, and a thresholdmetallic conductance at low temperatures could be achieved

  13. Enhanced tracer transport by the spiral defect chaos state of a convecting fluid

    E-Print Network [OSTI]

    K. -H. Chiam; M. C. Cross; H. S. Greenside; P. F. Fischer

    2004-09-23

    To understand how spatiotemporal chaos may modify material transport, we use direct numerical simulations of the three-dimensional Boussinesq equations and of an advection-diffusion equation to study the transport of a passive tracer by the spiral defect chaos state of a convecting fluid. The simulations show that the transport is diffusive and is enhanced by the spatiotemporal chaos. The enhancement in tracer diffusivity follows two regimes. For large Peclet numbers (that is, small molecular diffusivities of the tracer), we find that the enhancement is proportional to the Peclet number. For small Peclet numbers, the enhancement is proportional to the square root of the Peclet number. We explain the presence of these two regimes in terms of how the local transport depends on the local wave numbers of the convection rolls. For large Peclet numbers, we further find that defects cause the tracer diffusivity to be enhanced locally in the direction orthogonal to the local wave vector but suppressed in the direction of the local wave vector.

  14. Coulomb screening in graphene with topological defects

    E-Print Network [OSTI]

    Baishali Chakraborty; Kumar S. Gupta; Siddhartha Sen

    2015-02-20

    We analyze the screening of an external Coulomb charge in gapless graphene cone, which is taken as a prototype of a topological defect. In the subcritical regime, the induced charge is calculated using both the Green's function and the Friedel sum rule. The dependence of the polarization charge on the Coulomb strength obtained from the Green's function clearly shows the effect of the conical defect and indicates that the critical charge itself depends on the sample topology. Similar analysis using the Friedel sum rule indicates that the two results agree for low values of the Coulomb charge but differ for the higher strengths, especially in the presence of the conical defect. For a given subcritical charge, the transport cross-section has a higher value in the presence of the conical defect. In the supercritical regime we show that the coefficient of the power law tail of polarization charge density can be expressed as a summation of functions which vary log periodically with the distance from the Coulomb impurity. The period of variation depends on the conical defect. In the presence of the conical defect, the Fano resonances begin to appear in the transport cross-section for a lower value of the Coulomb charge. For both sub and supercritical regime we derive the dependence of LDOS on the conical defect. The effects of generalized boundary condition on the physical observables are also discussed.

  15. Comparison of quantization of charge transport in periodic and open pumps

    E-Print Network [OSTI]

    Comparison of quantization of charge transport in periodic and open pumps G.M. Graf and G. Ortelli the charges transported in two systems, a spatially periodic and an open quantum pump, both depending physical situations become the same, i.e., that of a large open pump. 1 Introduction In this note we

  16. Controllable spin-charge transport in strained graphene nanoribbon devices

    SciTech Connect (OSTI)

    Diniz, Ginetom S., E-mail: ginetom@gmail.com; Guassi, Marcos R. [Institute of Physics, University of Braslia, 70919-970, Braslia-DF (Brazil); Qu, Fanyao [Institute of Physics, University of Braslia, 70919-970, Braslia-DF (Brazil); Department of Physics, The University of Texas at Austin, Austin, Texas 78712 (United States)

    2014-09-21

    We theoretically investigate the spin-charge transport in two-terminal device of graphene nanoribbons in the presence of a uniform uniaxial strain, spin-orbit coupling, exchange field, and smooth staggered potential. We show that the direction of applied strain can efficiently tune strain-strength induced oscillation of band-gap of armchair graphene nanoribbon (AGNR). It is also found that electronic conductance in both AGNR and zigzag graphene nanoribbon (ZGNR) oscillates with Rashba spin-orbit coupling akin to the Datta-Das field effect transistor. Two distinct strain response regimes of electronic conductance as function of spin-orbit couplings magnitude are found. In the regime of small strain, conductance of ZGNR presents stronger strain dependence along the longitudinal direction of strain. Whereas for high values of strain shows larger effect for the transversal direction. Furthermore, the local density of states shows that depending on the smoothness of the staggered potential, the edge states of AGNR can either emerge or be suppressed. These emerging states can be determined experimentally by either spatially scanning tunneling microscope or by scanning tunneling spectroscopy. Our findings open up new paradigms of manipulation and control of strained graphene based nanostructure for application on novel topological quantum devices.

  17. Charged Particle Energization and Transport in the Magnetotail during Substorms

    E-Print Network [OSTI]

    Pan, Qingjiang

    2015-01-01

    energy and high-energy particles are transported along flowsimilar energies and pitch angles are not only transportedenergy electron fluxes: (1) hot and tenuous plasmas are transported

  18. Influence of defects on the charge density wave of ([SnSe]1+?)1(VSe2)1 ferecrystals

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Falmbigl, Matthias; Putzky, Daniel; Ditto, Jeffrey; Esters, Marco; Bauers, Sage R.; Ronning, Filip; Johnson, David C.

    2015-07-14

    A series of ferecrystalline compounds ([SnSe]1+?)1(VSe2)1 with varying Sn/V ratios were synthesized using the modulated elemental reactant technique. Temperature-dependent specific heat data reveal a phase transition at 102 K, where the heat capacity changes abruptly. An abrupt increase in electrical resistivity occurs at the same temperature, correlated with an abrupt increase in the Hall coefficient. Combined with the magnitude and nature of the specific heat discontinuity, this suggests that the transition is similar to the charge density wave transitions in transition metal dichalcogenides. An ordered intergrowth was formed over a surprisingly wide compositional range of Sn/V ratios of 0.89 ?more1 + ? ? 1.37. X-ray diffraction and transmission electron microscopy reveal the formation of various volume defects in the compounds in response to the nonstoichiometry. The electrical resistivity and Hall coefficient data of samples with different Sn/V ratios show systematic variation in the carrier concentration with the Sn/V ratio. There is no significant change in the onset temperature of the charge density wave transition, only a variation in the carrier densities before and after the transition. Given the sensitivity of the charge density wave transitions of transition metal dichalcogenides to variations in composition, it is very surprising that the charge density wave transition observed at 102 K for ([SnSe]1.15)1(VSe2)1 is barely influenced by the nonstoichiometry and structural defects. As a result, this might be a consequence of the two-dimensional nature of the structurally independent VSe2 layers.less

  19. ChargePoint is Helping Electrify America's Transportation | Department...

    Broader source: Energy.gov (indexed) [DOE]

    of plug-in electric vehicles (PEVs), the Energy Department supported the ChargePoint America project in 2009 under the American Recovery and Reinvestment Act. At the...

  20. Spin and Charge Quantum Transport in Organic/Magnetic Heterostructures for Spintronics and Optoelectronic

    E-Print Network [OSTI]

    Yeh, Nai-Chang

    Spin and Charge Quantum Transport in Organic/Magnetic Heterostructures for Spintronics to optimizing the spintronic and optoelectronic properties of organic semiconductor/ferromagnet heterostructures. "Spintronics" is a new electronics paradigm based on manipulation and detection of the spin

  1. Quasi-Ohmic Single Molecule Charge Transport through Highly Conjugated meso-to-meso Ethyne-

    E-Print Network [OSTI]

    Borguet, Eric

    S-1 Quasi-Ohmic Single Molecule Charge Transport through Highly Conjugated meso-to-meso Ethyne, subjected to three freeze-pump-thaw- degas cycles, was added to the reaction tube. After the reaction

  2. Erratum: "Conformations and charge transport characteristics of biphenyldithiol self-assembled-monolayer molecular electronic devices

    E-Print Network [OSTI]

    Goddard III, William A.

    Erratum: "Conformations and charge transport characteristics of biphenyldithiol self-Hoon Kim Materials and Process Simulation Center, California Institute of Technology, Pasadena, California, California Institute of Technology, Pasadena, California 91125-7400 Received 18 August 2005; accepted 6

  3. Conformations and charge transport characteristics of biphenyldithiol self-assembled-monolayer molecular electronic devices

    E-Print Network [OSTI]

    Goddard III, William A.

    Conformations and charge transport characteristics of biphenyldithiol self Simulation Center, California Institute of Technology, Pasadena, California 91125-7400 and Korea Institute and William A. Goddard IIIb Materials and Process Simulation Center, California Institute of Technology

  4. Impact of defects on the electrical transport, optical properties and failure mechanisms of GaN nanowires.

    SciTech Connect (OSTI)

    Armstrong, Andrew M.; Aubry, Sylvie; Shaner, Eric Arthur; Siegal, Michael P.; Li, Qiming; Jones, Reese E.; Westover, Tyler; Wang, George T.; Zhou, Xiao Wang; Talin, Albert Alec; Bogart, Katherine Huderle Andersen; Harris, C. Thomas; Huang, Jian Yu

    2010-09-01

    We present the results of a three year LDRD project that focused on understanding the impact of defects on the electrical, optical and thermal properties of GaN-based nanowires (NWs). We describe the development and application of a host of experimental techniques to quantify and understand the physics of defects and thermal transport in GaN NWs. We also present the development of analytical models and computational studies of thermal conductivity in GaN NWs. Finally, we present an atomistic model for GaN NW electrical breakdown supported with experimental evidence. GaN-based nanowires are attractive for applications requiring compact, high-current density devices such as ultraviolet laser arrays. Understanding GaN nanowire failure at high-current density is crucial to developing nanowire (NW) devices. Nanowire device failure is likely more complex than thin film due to the prominence of surface effects and enhanced interaction among point defects. Understanding the impact of surfaces and point defects on nanowire thermal and electrical transport is the first step toward rational control and mitigation of device failure mechanisms. However, investigating defects in GaN NWs is extremely challenging because conventional defect spectroscopy techniques are unsuitable for wide-bandgap nanostructures. To understand NW breakdown, the influence of pre-existing and emergent defects during high current stress on NW properties will be investigated. Acute sensitivity of NW thermal conductivity to point-defect density is expected due to the lack of threading dislocation (TD) gettering sites, and enhanced phonon-surface scattering further inhibits thermal transport. Excess defect creation during Joule heating could further degrade thermal conductivity, producing a viscous cycle culminating in catastrophic breakdown. To investigate these issues, a unique combination of electron microscopy, scanning luminescence and photoconductivity implemented at the nanoscale will be used in concert with sophisticated molecular-dynamics calculations of surface and defect-mediated NW thermal transport. This proposal seeks to elucidate long standing material science questions for GaN while addressing issues critical to realizing reliable GaN NW devices.

  5. Comparison of quantization of charge transport in periodic and open pumps

    E-Print Network [OSTI]

    Gian Michele Graf; Gregorio Ortelli

    2007-09-19

    We compare the charges transported in two systems, a spatially periodic and an open quantum pump, both depending periodically and adiabatically on time. The charge transported in a cycle was computed by Thouless, respectively by Buttiker et al. in the two cases. We show that the results agree in the limit where the two physical situations become the same, i.e., that of a large open pump.

  6. Surface-Plasmon Assisted Exciton and Charge Carrier Transport...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Piryatinski-photo000 Abstract: The ability to precisely control optical and transport properties of nanostructured materials opens up possibility of their use as functional...

  7. Influence of Topological Spin Fluctuations on Charge Transport

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    near 11 eV. The PrincetonALS group performed a detailed investigation of low-energy electronic structure and charge dynamics of the parent cobaltite compound Na0.7CoO2 at ALS...

  8. Holographic charge transport in non commutative gauge theories

    E-Print Network [OSTI]

    Dibakar Roychowdhury

    2015-07-01

    In this paper, based on the holographic techniques, we explore the hydrodynamics of charge diffusion phenomena in non commutative $ \\mathcal{N}=4 $ SYM plasma at strong coupling. In our analysis, we compute the $ R $ charge diffusion rates both along commutative as well as the non commutative coordinates of the brane. It turns out that unlike the case for the shear viscosity, the DC conductivity along the non commutative direction of the brane differs significantly from that of its cousin corresponding to the commutative direction of the brane. Such a discrepancy however smoothly goes away in the limit of the vanishing non commutativity.

  9. ChargePoint is Helping Electrify America's Transportation | Department of

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergy A plug-in electric vehicle (PEV) charging station in Rhode Island. | Photo courtesy

  10. Charging Up with the Electric Drive Transportation Association | Department

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergy A plug-in electric vehicle (PEV) charging station in Rhode Island. | Photo

  11. Charge transport and memristive properties of graphene quantum dots embedded in poly(3-hexylthiophene) matrix

    SciTech Connect (OSTI)

    Cosmin Obreja, Alexandru; Cristea, Dana; Radoi, Antonio; Gavrila, Raluca; Comanescu, Florin; Kusko, Cristian; Mihalache, Iuliana

    2014-08-25

    We show that graphene quantum dots (GQD) embedded in a semiconducting poly(3-hexylthiophene) polymeric matrix act as charge trapping nanomaterials. In plane current-voltage (I-V) measurements of thin films realized from this nanocomposite deposited on gold interdigitated electrodes revealed that the GQD enhanced dramatically the hole transport. I-V characteristics exhibited a strong nonlinear behavior and a pinched hysteresis loop, a signature of a memristive response. The transport properties of this nanocomposite were explained in terms of a trap controlled space charge limited current mechanism.

  12. Charge carrier transport and separation in pristine and nitrogen-doped graphene nanowiggle heterostructures

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lherbier, Aurlien; Liang, Liangbo; Charlier, Jean -Christophe; Meunier, Vincent

    2015-09-03

    Electronic structure methods are combined into a multiscale framework to investigate the electronic transport properties of recently synthesized pristine and nitrogen-doped graphene nanowiggles and their heterojunctions deposited on a substrate. The real-space Kubo-Greenwood transport calculations reveal that charge carrier mobilities reach values up to 1,000 cm2 V1 s1 as long as the amount of substrate impurities is sufficiently low. Owing to their type-II band alignment, atomically precise heterostructures between pristine and N-doped graphene nanowiggles are predicted to be excellent candidates for charge carrier separation devices with potential in photoelectric and photocatalytic water splitting applications.

  13. Quantum chemistry and charge transport in biomolecules with superconducting circuits

    E-Print Network [OSTI]

    L. Garca-lvarez; U. Las Heras; A. Mezzacapo; M. Sanz; E. Solano; L. Lamata

    2015-11-30

    We propose an efficient protocol for digital quantum simulation of quantum chemistry problems and enhanced digital-analog quantum simulation of transport phenomena in biomolecules with superconducting circuits. Along these lines, we prove that fermionic models of molecular structure can be optimally digitalized with single-qubit and two-qubit gates, by means of Trotter-Suzuki decomposition and Jordan-Wigner transformation. Furthermore, we address the modelling of system-environment interactions of biomolecules involving bosonic degrees of freedom with a digital-analog approach. Finally, we consider gate-truncated quantum algorithms to allow the study of environmental effects.

  14. Polymer Nanofibers and Nanotubes: Charge Transport and Device Applications

    E-Print Network [OSTI]

    Andrey N. Aleshin

    2007-01-31

    A critical analysis of recent advances in synthesis and electrical characterization of nanofibers and nanotubes made of different conjugated polymers is presented. The applicability of various theoretical models is considered in order to explain results on transport in conducting polymer nanofibers and nanotubes. The relationship between these results and the one-dimensional (1D) nature of the conjugated polymers is discussed in light of theories for tunneling in 1D conductors (e.g. Luttinger liquid, Wigner crystal). The prospects for nanoelectronic applications of polymer fibers and tubes as wires, nanoscale field-effect transistors (nanoFETs), and in other applications are analyzed.

  15. Transport of charged dust grains into the galactic halo

    E-Print Network [OSTI]

    Khoperskov, S A

    2014-01-01

    We develop a 3D dynamical model of dust outflows from galactic discs. The outflows are initiated by multiple SN explosions in a magnetized interstellar medium (ISM) with a gravitationally stratified density distribution. Dust grains are treated as particles in cells interacting collisionally with gas, and forced by stellar radiation of the disc and Lorenz force. We show that magnetic field plays a crucial role in accelerating the charged dust grains and expelling them out of the disc: in 10--20~Myr they can be elevated at distances up to 10~kpc above the galactic plane. The dust-to-gas ratio in the outflowing medium varies in the range $5 \\cdot 10^{-4} - 5 \\cdot 10^{-2}$ along the vertical stream. Overall the dust mass loss rate depends on the parameters of ISM and may reach up to $3\\times 10^{-2}$~\\Msun~yr$^{-1}$

  16. Knockout of the folate transporter folt-1 causes germline and somatic defects in C. elegans

    E-Print Network [OSTI]

    Austin, Misa U; Liau, Wei-Siang; Balamurugan, Krishnaswamy; Ashokkumar, Balasubramaniem; Said, Hamid M; LaMunyon, Craig W

    2010-01-01

    dehydrogenase cytochrome b causes oxidative stress andof the folate transporter folt-1 causes germline and somaticof the folate transporter folt-1 causes germline and somatic

  17. An Investigation of Spin and Charge Transport in Doped and Defected Graphene

    E-Print Network [OSTI]

    McCreary, Kathleen M.

    2012-01-01

    7.2 Sample Preparation Single layer graphene is obtained8.2 Sample Preparation: Single layer graphene (SLG) spinGraphene 81 6.1 Introduction.82 6.2 Sample Preparation..

  18. An Investigation of Spin and Charge Transport in Doped and Defected Graphene

    E-Print Network [OSTI]

    McCreary, Kathleen M.

    2012-01-01

    edges: Basis for novel spintronics devices. Phys. Rev. Lett.in Graphene Abstract: Spintronics is an emerging field ofI. Zutic, Semiconductor spintronics. Acta Phys. Slovaca 57 ,

  19. An Investigation of Spin and Charge Transport in Doped and Defected Graphene

    E-Print Network [OSTI]

    McCreary, Kathleen M.

    2012-01-01

    31, 32). Historically, spintronic investigations involvingthe electronic and spintronic properties of graphene

  20. An Investigation of Spin and Charge Transport in Doped and Defected Graphene

    E-Print Network [OSTI]

    McCreary, Kathleen M.

    2012-01-01

    hydrogenated epitaxial graphene. Appl. Phys. Lett. 98,of magnetoconductance in graphene devices. Phys. Rev. B 83,carrier mobilities in graphene and its bilayer. Phys. Rev.

  1. An Investigation of Spin and Charge Transport in Doped and Defected Graphene

    E-Print Network [OSTI]

    McCreary, Kathleen M.

    2012-01-01

    and graphite a semiconductor, graphene is a semi-metal, withgraphene: Evidence of a two- dimensional wide bandgap semiconductor.semiconductors (8-11), and carbon nanotubes (12, 13). In the short time since its discovery, graphene

  2. Anomalously augmented charge transport capabilities of biomimetically transformed collagen intercalated nano graphene based biocolloids

    E-Print Network [OSTI]

    Dhar, Purbarun; Nayar, Suprabha; Das, Sarit K

    2015-01-01

    Collagen micro fibrils bio mimetically intercalate graphitic structures in aqueous media to form graphene nano platelets collagen complex (G Cl). Synthesized G Cl based stable, aqueous bio nanocolloids exhibit anomalously augmented charge transportation capabilities over simple collagen or graphene based colloids. The concentration tunable electrical transport properties of synthesized aqueous G Cl bio nanocolloids has been experimentally observed, theoretically analyzed and mathematically modeled. A comprehensive approach to mathematically predict the electrical transport properties of simple graphene and collagen based colloids has been presented. A theoretical formulation to explain the augmented transport characteristics of the G Cl bio nanocolloids based on the physico chemical interactions among the two entities, as revealed from extensive characterizations of the G Cl bio complex, has also been proposed. Physical interactions between the zwitterionic amino acid molecules within the collagen triple heli...

  3. Mesoscale Phase-Field Modeling of Charge Transport in Nanocomposite Electrodes for Lithium-ion Batteries

    SciTech Connect (OSTI)

    Hu, Shenyang Y.; Li, Yulan; Rosso, Kevin M.; Sushko, Maria L.

    2013-01-10

    A phase-field model is developed to investigate the influence of microstructure, thermodynamic and kinetic properties, and charging conditions on charged particle transport in nanocomposite electrodes. Two sets of field variables are used to describe the microstructure. One is comprised of the order parameters describing size, orientation and spatial distributions of nanoparticles, and the other is comprised of the concentrations of mobile species. A porous nanoparticle microstructure filled with electrolyte is taken as a model system to test the phase-field model. Inhomogeneous and anisotropic dielectric constants and mobilities of charged particles, and stresses associated with lattice deformation due to Li-ion insertion/extraction are considered in the model. Iteration methods are used to find the elastic and electric fields in an elastically and electrically inhomogeneous medium. The results demonstrate that the model is capable of predicting charge separation associated with the formation of a double layer at the electrochemical interface between solid and electrolyte, and the effect of microstructure, inhomogeneous and anisotropic thermodynamic and kinetic properties, charge rates, and stresses on voltage versus current density and capacity during charging and discharging.

  4. Charge transport mechanisms of graphene/semiconductor Schottky barriers: A theoretical and experimental study

    SciTech Connect (OSTI)

    Zhong, Haijian; Liu, Zhenghui; Xu, Gengzhao; Shi, Lin; Fan, Yingmin; Yang, Hui [Suzhou Institute of Nano-Tech and Nano-Bionics, CAS, Suzhou 215123 (China); Xu, Ke, E-mail: kxu2006@sinano.ac.cn; Wang, Jianfeng; Ren, Guoqiang [Suzhou Institute of Nano-Tech and Nano-Bionics, CAS, Suzhou 215123 (China); Suzhou Nanowin Science and Technology Co., Ltd., Suzhou 215123 (China)

    2014-01-07

    Graphene has been proposed as a material for semiconductor electronic and optoelectronic devices. Understanding the charge transport mechanisms of graphene/semiconductor Schottky barriers will be crucial for future applications. Here, we report a theoretical model to describe the transport mechanisms at the interface of graphene and semiconductors based on conventional semiconductor Schottky theory and a floating Fermi level of graphene. The contact barrier heights can be estimated through this model and be close to the values obtained from the experiments, which are lower than those of the metal/semiconductor contacts. A detailed analysis reveals that the barrier heights are as the function of the interface separations and dielectric constants, and are influenced by the interfacial states of semiconductors. Our calculations show how this behavior of lowering barrier heights arises from the Fermi level shift of graphene induced by the charge transfer owing to the unique linear electronic structure.

  5. Controlling charge transport in blue organic light-emitting devices by chemical functionalization of host materials

    SciTech Connect (OSTI)

    Polikarpov, Evgueni; Koech, Phillip K.; Wang, Liang; Swensen, James S.; Cosimbescu, Lelia; Rainbolt, James E.; Von Ruden, Amber L.; Gaspar, Daniel J.; Padmaperuma, Asanga B.

    2011-01-18

    Generation of white light from OLEDs for general lighting applications requires a highly efficient blue component. However, a stable and power efficient blue OLED component with simple device architecture remains a significant challenge partly due to lack of appropriate host materials. Here we report the photophysical and device properties of ambipolar host phosphine oxide based materials. In this work, we studied the effect of the structural modification made to phosphine oxide-based hosts on the charge balance. We observed significant changes in charge transport within the host occurred upon small modifications to their chemical structure. As a result, an alteration of the chemical design of these materials allows for the control of charge balance of the OLED.

  6. Space charge compensation on the low energy beam transport of Linac4

    E-Print Network [OSTI]

    AUTHOR|(SzGeCERN)733270; Scrivens, Richard; Jesus Castillo, Santos

    Part of the upgrade program in the injector chains of the CERN accelerator complex is the replacement of the the proton accelerator Linac2 for the brand new Linac4 which will accelerate H$^-$ and its main goal is to increase the beam intensity in the next sections of the LHC accelerator chain. The Linac4 is now under commissioning and will use several ion sources to produce high intensity unbunched H$^-$ beams with different properties, and the low energy beam transport (LEBT) is the system in charge of match all these different beams to the Radio frequency quadrupole (RFQ). The space charge forces that spread the beam ions apart of each other and cause emittance growth limits the maximum intensity that can be transported in the LEBT, but the space charge of intense unbunched ion beams can be compensated by the generated ions by the impact ionization of the residual gas, which creates a source of secondary particles inside the beam pipe. For negative ion beams, the effect of the beam electric field is to ex...

  7. Redox probing study of the potential dependence of charge transport through Li2O2

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Knudsen, Kristian B.; Luntz, Alan C.; Jensen, Sren H.; Vegge, Tejs; Hjelm, Johan

    2015-11-20

    In the field of energy storage devices the pursuit for cheap, high energy density, reliable secondary batteries is at the top of the agenda. The LiO2 battery is one of the possible technologies that, in theory, should be able to close the gap, which exists between the present state-of-the-art Li-ion technologies and the demand placed on batteries by technologies such as electrical vehicles. Here we present a redox probing study of the charge transfer across the main deposition product lithium peroxide, Li2O2, in the LiO2 battery using outer-sphere redox shuttles. The change in heterogeneous electron transfer exchange rate as amorefunction of the potential and the Li2O2 layer thickness (~depth-of-discharge) was determined using electrochemical impedance spectroscopy. In addition, the attenuation of the electron transfer exchange rate with film thickness is dependent on the probing potential, providing evidence that hole transport is the dominant process for charge transfer through Li2O2 and showing that the origin of the sudden death observed upon discharge is due to charge transport limitations.less

  8. Computer Simulation of Defects and Oxygen Transport in Yttria-Stabilized Zirconia

    SciTech Connect (OSTI)

    Devanathan, Ram; Weber, William J.; Singhal, Subhash C.; Gale, Julian D.

    2006-06-15

    We have used molecular dynamics simulations and energy minimization calculations to examine defect energetics and oxygen diffusion in yttria-stabilized zirconia (YSZ). Oxygen vacancies prefer to be second nearest neighbors to yttrium dopants. The oxygen diffusion coefficient shows a peak at 8 mole % yttria consistent with experimental findings. The activation energy for oxygen diffusion varies from 0.6 to 1.0 eV depending on the yttria content. The Y-Vo-Y complex with a binding energy of -0.85 eV may play an important role in any conductivity degradation of YSZ.

  9. Methods for two-dimensional charged-particle transport in collisionless plasmas

    SciTech Connect (OSTI)

    Forslund, D.W.; Brackbill, J.U.

    1982-01-01

    A new method for modeling multi-dimensional charged particle transport in self-consistent electric and magnetic fields is presented. An implicit formulation of the Vlasov-Maxwell equations removes the usual restrictions on time and mesh spacing so that low frequency and large scale-length plasma phenomena can be studied. The improvement over previous explicit methods is literally orders of magnitude. As developed in a new code VENUS, we describe the algorithm and its stability and accuracy properties. This method allows one to bridge the enormous gap between the high frequency short scale-length collective plasma phenomena and the slow time scales and large-scale lengths of hydrodynamic processes. It should result in a significant improvement of phenomenological models of transport in existing hydrodynamics codes. Applications are given that include the discovery of the important role of self-generated magnetic fields in the convective transport of electron energy in laser irradiated plasmas. The transport, which occurs in the magnetized collisionless plasma corona, carries energy large distances from the laser deposition region in agreement with a wide variety of experimental data on apparent inhibited electron transport and fast ion loss.

  10. Charge transport in molecular junctions: From tunneling to hopping with the probe technique

    E-Print Network [OSTI]

    Kilgour, Michael

    2015-01-01

    We demonstrate that a simple phenomenological approach can be used to simulate electronic conduction in molecular wires under thermal effects induced by the surrounding environment. This "Landauer-B\\"uttiker's probe technique" can properly replicate different transport mechanisms: phase coherent nonresonant tunneling, ballistic behavior, and hopping conduction, to provide results consistent with experiments. Specifically, our simulations with the probe method recover the following central characteristics of charge transfer in molecular wires: (i) The electrical conductance of short wires falls off exponentially with molecular length, a manifestation of the tunneling (superexchange) mechanism. Hopping dynamics overtakes superexchange in long wires demonstrating an ohmic-like behavior. (ii) In off-resonance situations, weak dephasing effects facilitate charge transfer. Under large dephasing the electrical conductance is suppressed. (iii) At high enough temperatures, $k_BT/\\epsilon_B>1/25$, with $\\epsilon_B$ as ...

  11. Chiral vortical wave and induced flavor charge transport in a rotating quark-gluon plasma

    E-Print Network [OSTI]

    Jiang, Yin; Liao, Jinfeng

    2015-01-01

    We show the existence of a new gapless collective excitation in a rotating fluid system with chiral fermions, named as the Chiral Vortical Wave (CVW). The CVW has its microscopic origin at the quantum anomaly and macroscopically arises from interplay between vector and axial charge fluctuations induced by vortical effects. The wave equation is obtained both from hydrodynamic current equations and from chiral kinetic theory and its solutions show nontrivial CVW-induced charge transport from different initial conditions. Using the rotating quark-gluon plasma in heavy ion collisions as a concrete example, we show the formation of induced flavor quadrupole in QGP and estimate the elliptic flow splitting effect for Lambda baryons that may be experimentally measured.

  12. Nonequilibrium transport through quantum-wire junctions and boundary defects for free massless bosonic fields

    E-Print Network [OSTI]

    Gaw?dzki, Krzysztof

    2015-01-01

    We consider a model of quantum-wire junctions where the latter are described by conformal-invariant boundary conditions of the simplest type in the multicomponent compactified massless scalar free field theory representing the bosonized Luttinger liquids in the bulk of wires. The boundary conditions result in the scattering of charges across the junction with nontrivial reflection and transmission amplitudes. The equilibrium state of such a system, corresponding to inverse temperature $\\beta$ and electric potential $V$, is explicitly constructed both for finite and for semi-infinite wires. In the latter case, a stationary nonequilibrium state describing the wires kept at different temperatures and potentials may be also constructed. The main result of the present paper is the calculation of the full counting statistics (FCS) of the charge and energy transfers through the junction in a nonequilibrium situation. Explicit expressions are worked out for the generating function of FCS and its large-deviations asym...

  13. Nonequilibrium transport through quantum-wire junctions and boundary defects for free massless bosonic fields

    E-Print Network [OSTI]

    Krzysztof Gaw?dzki; Clment Tauber

    2015-01-29

    We consider a model of quantum-wire junctions where the latter are described by conformal-invariant boundary conditions of the simplest type in the multicomponent compactified massless scalar free field theory representing the bosonized Luttinger liquids in the bulk of wires. The boundary conditions result in the scattering of charges across the junction with nontrivial reflection and transmission amplitudes. The equilibrium state of such a system, corresponding to inverse temperature $\\beta$ and electric potential $V$, is explicitly constructed both for finite and for semi-infinite wires. In the latter case, a stationary nonequilibrium state describing the wires kept at different temperatures and potentials may be also constructed. The main result of the present paper is the calculation of the full counting statistics (FCS) of the charge and energy transfers through the junction in a nonequilibrium situation. Explicit expressions are worked out for the generating function of FCS and its large-deviations asymptotics. For the purely transmitting case they coincide with those obtained in the litterature, but numerous cases of junctions with transmission and reflection are also covered. The large deviations rate function of FCS for charge and energy transfers is shown to satisfy the fluctuation relations and the expressions for FCS obtained here are compared with the Levitov-Lesovic formulae.

  14. Efficiency of Charge Transport in a Polypeptide Chain: The Isolated System Sheh-Yi Sheu, E. W. Schlag,*, Dah-Yen Yang, and H. L. Selzle

    E-Print Network [OSTI]

    Sheu, Sheh-Yi

    Efficiency of Charge Transport in a Polypeptide Chain: The Isolated System Sheh-Yi Sheu, E. W and energy and hence provides a model for chemical reaction at a distance. The high efficiency of charge The protein interestingly shows a very much higher charge transport efficiency as an isolated molecule

  15. The Influence of Morphology on the Charge Transport in Two-Phase Disordered Organic Systems

    E-Print Network [OSTI]

    Cristiano F. Woellner; Leonardo D. Machado; Pedro A. S. Autreto; Jose A. Freire; Douglas S. Galvao

    2015-01-07

    In this work we use a three-dimensional Pauli master equation to investigate the charge carrier mobility of a two-phase system, which can mimic donor-acceptor and amorphous- crystalline bulk heterojunctions. Our approach can be separated into two parts: the morphology generation and the charge transport modeling in the generated blend. The morphology part is based on a Monte Carlo simulation of binary mixtures (donor/acceptor). The second part is carried out by numerically solving the steady-state Pauli master equation. By taking the energetic disorder of each phase, their energy offset and domain morphology into consideration, we show that the carrier mobility can have a significant different behavior when compared to a one-phase system. When the energy offset is non-zero, we show that the mobility electric field dependence switches from negative to positive at a threshold field proportional to the energy offset. Additionally, the influence of morphology, through the domain size and the interfacial roughness parameters, on the transport was also investigated.

  16. Studies on low energy beam transport for high intensity high charged ions at IMP

    SciTech Connect (OSTI)

    Yang, Y. Lu, W.; Fang, X.; University of Chinese Academy of Sciences, Beijing 100039 ; Sun, L. T.; Hu, Q.; Cao, Y.; Feng, Y. C.; Zhang, X. Z.; Zhao, H. W.; Xie, D. Z.

    2014-02-15

    Superconducting Electron Cyclotron Resonance ion source with Advanced design in Lanzhou (SECRAL) is an advanced fully superconducting ECR ion source at IMP designed to be operational at the microwave frequency of 1824 GHz. The existing SECRAL beam transmission line is composed of a solenoid lens and a 110 analyzing magnet. Simulations of particle tracking with 3D space charge effect and realistic 3D magnetic fields through the line were performed using particle-in-cell code. The results of the beam dynamics show that such a low energy beam is very sensitive to the space charge effect and significantly suffers from the second-order aberration of the analyzing magnet resulting in large emittance. However, the second-order aberration could be reduced by adding compensating sextupole components in the beam line. On this basis, a new 110 analyzing magnet with relatively larger acceptance and smaller aberration is designed and will be used in the design of low energy beam transport line for a new superconducting ECR ion source SECRAL-II. The features of the analyzer and the corresponding beam trajectory calculation will be detailed and discussed in this paper.

  17. Dielectric relaxation from a network of charged defects in dilute CeO/sub 2/:Y/sub 2/O/sub 3/ solid solutions

    SciTech Connect (OSTI)

    Wang, D.Y.; Nowick, A.S.

    1981-01-01

    Solid solutions of Y/sub 2/O/sub 3/ in CeO/sub 2/ are examined by the thermal depolarization (or ITC) method of dielectric relaxation. For concentrations less than or equal to 1 m/o Y/sub 2/O/sub 3/, two peaks are observed. The lower temperature peak, Peak 1, is interpreted as due to the relaxation of nn YV/sub 0/ pairs (where V/sub 0/ = oxygen vacancy, and is analogous to the well-known CaV/sub 0/ pair obtained with Ca/sup 2 +/ doping. The upper peak, Peak 2, on the other hand, is a broad peak whose position is a function of concentration. It is not due to simple dipoles, but originates in the network of alternately charged (YV/sub 0/)/sup ./ pairs and isolated Y' defects by redistribution of vacancies.

  18. Charge-transport-mediated recruitment of DNA repair enzymes Pak-Wing Fok,1,2,a

    E-Print Network [OSTI]

    Levine, Alex J.

    Charge-transport-mediated recruitment of DNA repair enzymes Pak-Wing Fok,1,2,a Chin-Lin Guo,3 and Tom Chou2,4,b 1 Applied and Computational Mathematics, California Institute of Technology, Pasadena, California 91125, USA 2 Department of Biomathematics, UCLA, Los Angeles, California 90095-1766, USA 3 Applied

  19. Transport of multiply and highly charged ions through nanoscale apertures in silicon nitride membranes

    E-Print Network [OSTI]

    . PACS: 34.50.Dy Keywords: Slow highly charged ions; Capillary transmission; Charge exchange 1-the-barrier model (COB) [47]. The model can be used to estimate the critical distance for charge transfer dc exchange of multiply and highly charged ions for transmission of aper- tures in silicon nitride targets

  20. Charge carrier transport mechanisms in perovskite CdTiO{sub 3} fibers

    SciTech Connect (OSTI)

    Imran, Z.; Rafiq, M. A. Hasan, M. M.

    2014-06-15

    Electrical transport properties of electrospun cadmium titanate (CdTiO{sub 3}) fibers have been investigated using ac and dc measurements. Air annealing of as spun fibers at 1000?C yielded the single phase perovskite fibers having diameter ?600 nm - 800 nm. Both the ac and dc electrical measurements were carried out at temperatures from 200 K 420 K. The complex impedance plane plots revealed a single semicircular arc which indicates the interfacial effect due to grain boundaries of fibers. The dielectric properties obey the Maxwell-Wagner theory of interfacial polarization. In dc transport study at low voltages, data show Ohmic like behavior followed by space charge limited current (SCLC) with traps at higher voltages at all temperatures (200 K 420 K). Trap density in our fibers system is N{sub t} = 6.27 10{sup 17} /cm{sup 3}. Conduction mechanism in the sample is governed by 3-D variable range hopping (VRH) from 200 K 300 K. The localized density of states were found to be N(E{sub F}) = 5.51 10{sup 21} eV{sup ?1} cm{sup ?3} at 2 V. Other VRH parameters such as hopping distance (R{sub hop}) and hopping energy (W{sub hop}) were also calculated. In the high temperature range of 320 K 420 K, conductivity follows the Arrhenius law. The activation energy found at 2 V is 0.10 eV. Temperature dependent and higher values of dielectric constant make the perovskite CdTiO{sub 3} fibers efficient material for capacitive energy storage devices.

  1. Mechanisms of charge transport in anisotype n-TiO{sub 2}/p-CdTe heterojunctions

    SciTech Connect (OSTI)

    Brus, V. V.; Ilashchuk, M. I.; Kovalyuk, Z. D.; Maryanchuk, P. D.; Ulyanytsky, K. S.; Gritsyuk, B. N.

    2011-08-15

    Surface-barrier anisotype n-TiO{sub 2}/p-CdTe heterojunctions are fabricated by depositing thin titanium-dioxide films on a freshly cleaved surface of single-crystalline cadmium-telluride wafers by reactive magnetron sputtering. It is established that the electric current through the heterojunctions under investigation is formed by generation-recombination processes in the space-charge region via a deep energy level and tunneling through the potential barrier. The depth and nature of the impurity centers involved in the charge transport are determined.

  2. Space-Charge Limits on the Transport of Ion Beams in a Long Alternating Gradient System

    E-Print Network [OSTI]

    Tiefenback, M.G.

    2011-01-01

    term stability of the transport of cold, high-current beams,beam. The cold-beam ideal case for this transport is called

  3. Charge transport through bio-molecular wires in a solvent: Bridging molecular dynamics and model Hamiltonian approaches

    E-Print Network [OSTI]

    R. Gutierrez; R. Caetano; P. B. Woiczikowski; T. Kubar; M. Elstner; G. Cuniberti

    2009-01-22

    We present a hybrid method based on a combination of quantum/classical molecular dynamics (MD) simulations and a mod el Hamiltonian approach to describe charge transport through bio-molecular wires with variable lengths in presence o f a solvent. The core of our approach consists in a mapping of the bio-molecular electronic structure, as obtained f rom density-functional based tight-binding calculations of molecular structures along MD trajectories, onto a low di mensional model Hamiltonian including the coupling to a dissipative bosonic environment. The latter encodes fluctuat ion effects arising from the solvent and from the molecular conformational dynamics. We apply this approach to the c ase of pG-pC and pA-pT DNA oligomers as paradigmatic cases and show that the DNA conformational fluctuations are essential in determining and supporting charge transport.

  4. The anomalous transport of axial charge: topological vs non-topological fluctuations

    E-Print Network [OSTI]

    Ioannis Iatrakis; Shu Lin; Yi Yin

    2015-08-16

    Axial charge imbalance is an essential ingredient in novel effects associated with chiral anomaly such as chiral magnetic effects (CME). In a non-Abelian plasma with chiral fermions, local axial charge can be generated a) by topological fluctuations which would create domains with non-zero winding number b) by conventional non-topological thermal fluctuations. We provide a holographic evaluations of medium's response to dynamically generated axial charge density in hydrodynamic limit and examine if medium's response depends on the microscopic origins of axial charge imbalance. We show a local domain with non-zero winding number would induce a non-dissipative axial current due to chiral anomaly. We illustrate holographically that a local axial charge imbalance would be damped out with the damping rate related to Chern-Simon diffusive constant. By computing chiral magnetic current in the presence of dynamically generated axial charge density, we found that the ratio of CME current over the axial charge density is independent of the origin of axial charge imbalance in low frequency and momentum limit. Finally, a stochastic hydrodynamic equation of the axial charge is formulated by including both types of fluctuations.

  5. Space-Charge Limits on the Transport of Ion Beams in a Long Alternating Gradient System

    E-Print Network [OSTI]

    Tiefenback, M.G.

    2011-01-01

    valve allowed access to the source housing while leaving the transport section under vacuum, greatly reducing the outgassing

  6. PROJECT PROFILE: High-resolution Investigations of Transport Limiting Defects and Interfaces in Thin-Film Photovoltaic Devices

    Broader source: Energy.gov [DOE]

    This project will develop the capability of high-resolution transport imaging in photovoltaic (PV) devices, which is useful for improving polycrystalline thin-film PV materials.

  7. In-situ optical measurement of charge transport dynamics in organic photovoltaics

    E-Print Network [OSTI]

    Chow, Philip C. Y.; Bayliss, Sam L.; Lakhwani, Girish; Greenham, Neil C.; Friend, Richard H.

    2015-01-13

    We present a novel experimental approach which allows extraction of both spatial and temporal information on charge dynamics in organic solar cells. Using the wavelength dependence of the photonic structure in these devices, we monitor the change...

  8. Charge-based transport and drug delivery into cartilage for localized treatment of degenerative joint diseases

    E-Print Network [OSTI]

    Bajpayee, Ambika Goel

    2015-01-01

    Traumatic joint injuries significantly increase synovial fluid levels of pro-inflammatory cytokines that can initiate cartilage degeneration leading to osteoarthritis (OA). Articular cartilage is a highly negatively charged, ...

  9. Femtosecond x-rays link melting of charge density wave correlations and light-enhanced coherent transport in YBa?Cu?O?.?

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Forst, M. [Max-Planck Inst. for the Structure and Dynamics of Matter, Hamburg (Germany); Hill, J. P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Frano, A. [Max-Planck Inst. for Solid State Research, Stuttgart (Germany); Helmholtz-Zentrum Berlin Fur Materialien und Energie, Berlin (Germany); Kaiser, S. [Max-Planck Inst. for the Structure and Dynamics of Matter, Hamburg (Germany); Mankowsky, R. [Max-Planck Inst. for the Structure and Dynamics of Matter, Hamburg (Germany); Hunt, C. R. [Max-Planck Inst. for the Structure and Dynamics of Matter, Hamburg (Germany); Univ. of Illinois at Urbana-Champaign, Urbana, IL (United States); Turner, J. J. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Dakovski, G. L. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Minitti, M. P. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Robinson, J. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Loew, T. [Max-Planck Inst. for Solid State Research, Stuttgart (Germany); Le Tacon, M. [Max-Planck Inst. for Solid State Research, Stuttgart (Germany); Keimer, B. [Max-Planck Inst. for Solid State Research, Stuttgart (Germany); Cavalleri, A. [Max-Planck Inst. for the Structure and Dynamics of Matter, Hamburg (Germany); Univ. of Oxford (United Kingdom); Dhesi, S. S. [Diamond Light Source, Chilton, Didcot (United Kingdom)

    2014-11-01

    We use femtosecond resonant soft x-ray diffraction to measure the optically stimulated ultrafast changes of charge density wave correlations in underdoped YBa?Cu?O?.?. We find that when coherent interlayer transport is enhanced by optical excitation of the apical oxygen distortions, at least 50% of the in-plane charge density wave order is melted. These results indicate that charge ordering and superconductivity may be competing up to the charge ordering transition temperature, with the latter becoming a hidden phase that is accessible only by nonlinear phonon excitation.

  10. Femtosecond x rays link melting of charge-density wave correlations and light-enhanced coherent transport in YBa2Cu3O6.6

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Frst, M.; Frano, A.; Kaiser, S.; Mankowsky, R.; Hunt, C. R.; Turner, J. J.; Dakovski, G. L.; Minitti, M. P.; Robinson, J.; Loew, T.; et al

    2014-11-17

    In this study, we use femtosecond resonant soft x-ray diffraction to measure the optically stimulated ultrafast changes of charge density wave correlations in underdoped YBa?Cu?O?.?. We find that when coherent interlayer transport is enhanced by optical excitation of the apical oxygen distortions, at least 50% of the in-plane charge density wave order is melted. These results indicate that charge ordering and superconductivity may be competing up to the charge ordering transition temperature, with the latter becoming a hidden phase that is accessible only by nonlinear phonon excitation.

  11. Femtosecond x-rays link melting of charge density wave correlations and light-enhanced coherent transport in YBa?Cu?O?.?

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Forst, M.; Hill, J. P.; Frano, A.; Kaiser, S.; Mankowsky, R.; Hunt, C. R.; Turner, J. J.; Dakovski, G. L.; Minitti, M. P.; Robinson, J.; et al

    2014-11-17

    We use femtosecond resonant soft x-ray diffraction to measure the optically stimulated ultrafast changes of charge density wave correlations in underdoped YBa?Cu?O?.?. We find that when coherent interlayer transport is enhanced by optical excitation of the apical oxygen distortions, at least 50% of the in-plane charge density wave order is melted. These results indicate that charge ordering and superconductivity may be competing up to the charge ordering transition temperature, with the latter becoming a hidden phase that is accessible only by nonlinear phonon excitation.

  12. Charge transport, configuration interaction and Rydberg states under density functional theory

    E-Print Network [OSTI]

    Cheng, Chiao-Lun

    2008-01-01

    Density functional theory (DFT) is a computationally efficient formalism for studying electronic structure and dynamics. In this work, we develop DFT-based excited-state methods to study electron transport, Rydberg excited ...

  13. Modification of space charge transport in nanocrystalline cerium oxide by heterogeneous doping

    E-Print Network [OSTI]

    Litzelman, Scott J

    2009-01-01

    In the search for new materials for energy conversion and storage technologies such as solid oxide fuel cells, nano-ionic materials have become increasingly relevant because unique physical and transport properties that ...

  14. Curl flux, coherence, and population landscape of molecular systems: Nonequilibrium quantum steady state, energy (charge) transport, and thermodynamics

    E-Print Network [OSTI]

    Zhedong Zhang; Jin Wang

    2015-12-25

    We established a theoretical framework in terms of the curl flux, population landscape, and coherence for non-equilibrium quantum systems at steady state, through exploring the energy and charge transport in molecular processes. The curl quantum flux plays the key role in determining transport properties and the system reaches equilibrium when flux vanishes. The novel curl quantum flux reflects the degree of non-equilibriumness and the time-irreversibility. We found an analytical expression for the quantum flux and its relationship to the environmental pumping (non-equilibriumness quantified by the voltage away from the equilibrium) and the quantum tunneling. Furthermore, we investigated another quantum signature, the coherence, quantitatively measured by the non-zero off diagonal element of the density matrix. Besides the environment-assistance which can give dramatic enhancement of coherence and quantum flux with high voltage at a fixed tunneling strength, the quantum flux is promoted by the coherence in the regime of small tunneling while reduced by the coherence in the regime of large tunneling, due to the non-monotonic relationship between the coherence and tunneling. In view of the system as a quantum heat engine, we studied the non-equilibrium thermodynamics and established the analytical connections of curl quantum flux to the transport quantities such as energy (charge) transfer efficiency, chemical reaction efficiency, energy dissipation, heat and electric currents observed in the experiments. We observed a perfect transfer efficiency in chemical reactions at high voltage (chemical potential difference). Our theoretical predicted behavior of the electric current with respect to the voltage is in good agreements with the recent experiments on electron transfer in single molecules.

  15. Adaptive Algorithm for Charged and Uncharged Particle Transport. Student : D. J. Koeze

    E-Print Network [OSTI]

    Vuik, Kees

    of solving the neutron transport equation. This equation tells us how neutrons behave in a absorbing and scattering medium. We can apply this equation in many fields, like in the design process of a nuclear power plant and in the research of materials with neutron beams. In a reactor core it is important to have

  16. Manifestation of the spin Hall effect through charge-transport in the mesoscopic regime

    E-Print Network [OSTI]

    Hankiewicz, EM; Molenkamp, LW; Jungwirth, T.; Sinova, Jairo.

    2004-01-01

    We study theoretically the manifestation of the spin Hall effect in a two-dimensional electronic system with Rashba spin-orbit coupling via dc-transport measurements in realistic mesoscopic H-shape structures. The Landauer-Buttiker formalism is used...

  17. Effects of Milan's Congestion Charge

    E-Print Network [OSTI]

    Carnovale, Maria; Gibson, Matthew

    2012-01-01

    Transportation Research Part A: Policy and Practice 44.5 [20] Transport for London,London, and Milan have congestion charges. In the US, the Department of Transportation

  18. Influence of plasma loss area on transport of charged particles through a transverse magnetic field

    SciTech Connect (OSTI)

    Das, B. K.; Chakraborty, M. [Centre of Plasma Physics-Institute for Plasma Research, Tepesia, Kamrup, Assam (India); Bandyopadhyay, M. [ITER-India, Institute for Plasma Research, Gandhinagar, Gujarat (India)

    2012-01-15

    Plasma transport in a double plasma device from the source region to the target region through a physical window comprising of electrically grounded magnet channels (filled with permanent magnet bars) for transverse magnetic field (TMF) and a pair of stainless steel (SS) plates is studied and presented in this manuscript. The study has relevance in negative ion source research and development where both TMF created by magnet channels and bias plate are used. The experiment is performed in two stages. In the first stage, a TMF is introduced between the two regions along with the SS plates, and corresponding plasma parameter data in the two regions are recorded by changing the distance between the TMF channels. In the second stage, the TMF is withdrawn from the system, and corresponding data are taken by changing the separation between the SS plates. The experimental results are then compared with a theoretical model. In the presence of TMF, where electrons are magnetized and ions are un-magnetized, it is observed that plasma transport perpendicular to the TMF is dominated by the ambipolar diffusion of ions. In the absence of TMF, plasma is un-magnetized, and plasma transport through the SS window aperture is almost independent of open area of the SS window.

  19. Influence of nanostructure on charge transport in RuO{sub 2} thin films

    SciTech Connect (OSTI)

    Steeves, M. M.; Lad, R. J.

    2010-07-15

    Polycrystalline thin films of RuO{sub 2} were grown on fused-quartz substrates and a parametric study was carried out to probe the influence of film nanostructure on the four-point Van der Pauw resistivity and Hall coefficient. The films were grown via reactive rf magnetron sputtering of a Ru target in an Ar/O{sub 2} plasma using deposition rates from 0.27 to 3.5 A/s and substrate temperatures from 16 to 500 deg. C Room-temperature resistivities of the RuO{sub 2} films ranged from 58 to 360 {mu}{Omega} cm. Upon first heating following deposition, some films showed decreasing resistivity with increasing temperature, but the resistivities also decreased upon subsequent cooling suggesting that the annealing treatment reduces the film defect density. The temperature coefficient of resistance was found to be small (<0.001 K{sup -1}) in agreement with previous investigations. Hall coefficient measurements of the polycrystalline thin films demonstrated that either n-type or p-type majority carriers can be present depending on deposition conditions and the resulting nanostructure, in contrast to single-crystal RuO{sub 2}, which is an n-type metal. Grain size and homogeneous strain within the films were measured by x-ray diffraction and are correlated to the majority carrier type.

  20. Transport properties of a charged drop in an external electromagnetic field

    E-Print Network [OSTI]

    S. Bondarenko; K. Komoshvili; A. Prygarin

    2015-10-26

    We investigate adiabatic expansion of a charged and rotating fireball consisting of weekly interacting particles, which is initially perturbed by an external electromagnetic field. A framework for the perturbative calculation of the non-equilibrium distribution function of the fireball is considered and the distribution function is calculated to the first order in the perturbative expansion. This distribution function, which describes the evolution of the droplet with constant entropy, allows to calculate momentum flux tensor and viscosity coefficients of the expanding system. We show, that these viscosity coefficients depend on the initial angular velocity of the fireball and on the strength of its initial perturbation by the external field. Obtained results are applied to the phenomenology of the viscosity to the entropy ratio calculated in lattice models.

  1. Transport properties of a charged drop in an external electromagnetic field

    E-Print Network [OSTI]

    Bondarenko, S; Prygarin, A

    2015-01-01

    We investigate adiabatic expansion of a charged and rotating fireball consisting of weekly interacting particles, which is initially perturbed by an external electromagnetic field. A framework for the perturbative calculation of the non-equilibrium distribution function of the fireball is considered and the distribution function is calculated to the first order in the perturbative expansion. This distribution function, which describes the evolution of the droplet with constant entropy, allows to calculate momentum flux tensor and viscosity coefficients of the expanding system. We show, that these viscosity coefficients depend on the initial angular velocity of the fireball and on the strength of its initial perturbation by the external field. Obtained results are applied to the phenomenology of the viscosity to the entropy ratio calculated in lattice models.

  2. Nonequilibrium density matrix for simultaneous heat and charge steady-state transport in quantum open systems

    E-Print Network [OSTI]

    H. Ness

    2014-12-02

    We suggest a generalisation of the expression of the nonequilibrium density matrix obtained by Hershfield's method for the cases where both heat and charge steady state currents are present in a quantum open system. The finite-size quantum system, connected to two temperature and particle reservoirs, is driven out of equilibrium by the presence of both a temperature gradient and a chemical potential gradient between the two reservoirs. We show that the NE density matrix is given by a generalised Gibbs-like ensemble, and is in full agreement with the general results of the McLennan-Zubarev nonequilibrium ensembles. The extra non-equilibrium terms are related to the entropy production in the system and characterise the fluxes of heat and particle.An explicit example, for the lowest order expansion, is provide for a model system of non-interacting fermions.

  3. Thermal influence on charge carrier transport in solar cells based on GaAs PN junctions

    SciTech Connect (OSTI)

    Osses-Mrquez, Juan; Caldern-Muoz, Williams R.

    2014-10-21

    The electron and hole one-dimensional transport in a solar cell based on a Gallium Arsenide (GaAs) PN junction and its dependency with electron and lattice temperatures are studied here. Electrons and heat transport are treated on an equal footing, and a cell operating at high temperatures using concentrators is considered. The equations of a two-temperature hydrodynamic model are written in terms of asymptotic expansions for the dependent variables with the electron Reynolds number as a perturbation parameter. The dependency of the electron and hole densities through the junction with the temperature is analyzed solving the steady-state model at low Reynolds numbers. Lattice temperature distribution throughout the device is obtained considering the change of kinetic energy of electrons due to interactions with the lattice and heat absorbed from sunlight. In terms of performance, higher values of power output are obtained with low lattice temperature and hot energy carriers. This modeling contributes to improve the design of heat exchange devices and thermal management strategies in photovoltaic technologies.

  4. Energy, Charge, and Spin Transport in Molecules and Self-Assembled Nanostructures Inspired by Photosynthesis

    SciTech Connect (OSTI)

    Wasielewski, Michael R. (NWU)

    2008-10-03

    Electron transfer in biological molecules provides both insight and inspiration for developing chemical systems having similar functionality. Photosynthesis is an example of an integrated system in which light harvesting, photoinduced charge separation, and catalysis combine to carry out two thermodynamically demanding processes, the oxidation of water and the reduction of carbon dioxide. The development of artificial photosynthetic systems for solar energy conversion requires a fundamental understanding of electron-transfer reactions between organic molecules. Since these reactions most often involve single-electron transfers, the spin dynamics of photogenerated radical ion pairs provide important information on how the rates and efficiencies of these reactions depend on molecular structure. Given this knowledge, the design and synthesis of large integrated structures to carry out artificial photosynthesis is moving forward. An important approach to achieving this goal is the development of small, functional building blocks, having a minimum number of covalent bonds, which also have the appropriate molecular recognition sites to facilitate self-assembly into a complete, functional artificial photosynthetic system.

  5. VOLUME 81, NUMBER 20 P H Y S I C A L R E V I E W L E T T E R S 16 NOVEMBER 1998 Essential Role of Correlations in Governing Charge Transport in Disordered Organic Materials

    E-Print Network [OSTI]

    Kenkre, V.M.

    of Correlations in Governing Charge Transport in Disordered Organic Materials S. V. Novikov,1,2 D. H. Dunlap,2 V (Received 26 May 1998) The transport of photoinjected charges in disordered organic films is often interpreted using a formula based on a Gaussian disorder model (GDM) that neglects spatial correlations due

  6. The impact of disorder on charge transport in three dimensional quantum dot resonant tunneling structures

    SciTech Connect (OSTI)

    Puthen-Veettil, B. Patterson, R.; Knig, D.; Conibeer, G.; Green, M. A.

    2014-10-28

    Efficient iso-entropic energy filtering of electronic waves can be realized through nanostructures with three dimensional confinement, such as quantum dot resonant tunneling structures. Large-area deployment of such structures is useful for energy selective contacts but such configuration is susceptible to structural disorders. In this work, the transport properties of quantum-dot-based wide-area resonant tunneling structures, subject to realistic disorder mechanisms, are studied. Positional variations of the quantum dots are shown to reduce the resonant transmission peaks while size variations in the device are shown to reduce as well as broaden the peaks. Increased quantum dot size distribution also results in a peak shift to lower energy which is attributed to large dots dominating transmission. A decrease in barrier thickness reduces the relative peak height while the overall transmission increases dramatically due to lower series resistance. While any shift away from ideality can be intuitively expected to reduce the resonance peak, quantification allows better understanding of the tolerances required for fabricating structures based on resonant tunneling phenomena/.

  7. Charged impurity-induced scatterings in chemical vapor deposited graphene

    SciTech Connect (OSTI)

    Li, Ming-Yang; Tang, Chiu-Chun [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Ling, D. C. [Department of Physics, Tamkang University, Tamsui Dist., New Taipei 25137, Taiwan (China); Li, L. J. [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 11529, Taiwan (China); Chi, C. C.; Chen, Jeng-Chung [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu 30013, Taiwan (China)

    2013-12-21

    We investigate the effects of defect scatterings on the electric transport properties of chemical vapor deposited (CVD) graphene by measuring the carrier density dependence of the magneto-conductivity. To clarify the dominant scattering mechanism, we perform extensive measurements on large-area samples with different mobility to exclude the edge effect. We analyze our data with the major scattering mechanisms such as short-range static scatters, short-range screened Coulomb disorders, and weak-localization (WL). We establish that the charged impurities are the predominant scatters because there is a strong correlation between the mobility and the charge impurity density. Near the charge neutral point (CNP), the electron-hole puddles that are induced by the charged impurities enhance the inter-valley scattering, which is favorable for WL observations. Away from the CNP, the charged-impurity-induced scattering is weak because of the effective screening by the charge carriers. As a result, the local static structural defects govern the charge transport. Our findings provide compelling evidence for understanding the scattering mechanisms in graphene and pave the way for the improvement of fabrication techniques to achieve high-quality CVD graphene.

  8. Improvement of charged particles transport across a transverse magnetic filter field by electrostatic trapping of magnetized electrons

    SciTech Connect (OSTI)

    Das, B. K. Hazarika, P.; Chakraborty, M.; Bandyopadhyay, M.

    2014-07-15

    A study on the transport of charged particles across a magnetic filter field has been carried out in a double plasma device (DPD) and presented in this manuscript. The DPD is virtually divided into two parts viz. source and target regions by a transverse magnetic field (TMF) which is constructed by inserting strontium ferrite magnets into two stainless steel rectangular tubes. Plasma electrons are magnetized but ions are unmagnetized inside the TMF region. Negative voltages are applied to the TMF tubes in order to reduce the loss of electrons towards them. Plasma is produced in the source region by filament discharge method and allowed to flow towards the target region through this negatively biased TMF. It is observed that in the target region, plasma density can be increased and electron temperature decreased with the help of negatively biased TMF. This observation is beneficial for negative ion source development. Plasma diffusion across the negatively biased TMF follows Bohm or anomalous diffusion process when negative bias voltage is very less. At higher negative bias, diffusion coefficient starts deviating from the Bohm diffusion value, associated with enhanced plasma flow in the target region.

  9. Novel Energy Sources -Material Architecture and Charge Transport in Solid State Ionic Materials for Rechargeable Li ion Batteries

    SciTech Connect (OSTI)

    Katiyar, Ram S; Gmez, M; Majumder, S B; Morell, G; Tomar, M S; Smotkin, E; Bhattacharya, P; Ishikawa, Y

    2009-01-19

    Since its introduction in the consumer market at the beginning of 1990s by Sony Corporation Li-ion rechargeable battery and LiCoO2 cathode is an inseparable couple for highly reliable practical applications. However, a separation is inevitable as Li-ion rechargeable battery industry demand more and more from this well serving cathode. Spinel-type lithium manganate (e.g., LiMn2O4), lithium-based layered oxide materials (e.g., LiNiO2) and lithium-based olivine-type compounds (e.g., LiFePO4) are nowadays being extensively studied for application as alternate cathode materials in Li-ion rechargeable batteries. Primary goal of this project was the advancement of Li-ion rechargeable battery to meet the future demands of the energy sector. Major part of the research emphasized on the investigation of electrodes and solid electrolyte materials for improving the charge transport properties in Li-ion rechargeable batteries. Theoretical computational methods were used to select electrodes and electrolyte material with enhanced structural and physical properties. The effect of nano-particles on enhancing the battery performance was also examined. Satisfactory progress has been made in the bulk form and our efforts on realizing micro-battery based on thin films is close to give dividend and work is progressing well in this direction.

  10. Space-charge compensation measurements in electron cyclotron resonance ion source low energy beam transport lines with a retarding field analyzer

    SciTech Connect (OSTI)

    Winklehner, D.; Leitner, D., E-mail: leitnerd@nscl.msu.edu; Cole, D.; Machicoane, G.; Tobos, L. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)] [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)

    2014-02-15

    In this paper we describe the first systematic measurement of beam neutralization (space charge compensation) in the ECR low energy transport line with a retarding field analyzer, which can be used to measure the potential of the beam. Expected trends for the space charge compensation levels such as increase with residual gas pressure, beam current, and beam density could be observed. However, the overall levels of neutralization are consistently low (<60%). The results and the processes involved for neutralizing ion beams are discussed for conditions typical for ECR injector beam lines. The results are compared to a simple theoretical beam plasma model as well as simulations.

  11. Self healing of defected graphene

    SciTech Connect (OSTI)

    Chen, Jianhui; Shi, Tuwan; Cai, Tuocheng; Wu, Xiaosong; Yu, Dapeng [School of Physics, Peking University, Beijing 100871 (China) [School of Physics, Peking University, Beijing 100871 (China); State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, Peking University, Beijing 100871 (China); Xu, Tao; Sun, Litao [SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, Southeast University, Nanjing 210096 (China)] [SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, Southeast University, Nanjing 210096 (China)

    2013-03-11

    For electronics applications, defects in graphene are usually undesirable because of their ability to scatter charge carriers, thereby reduce the carrier mobility. It would be extremely useful if the damage can be repaired. In this work, we employ Raman spectroscopy, X-ray photoemission spectroscopy, transmission electron microscopy, and electrical measurements to study defects in graphene introduced by argon plasma bombardment. We have found that majority of these defects can be cured by a simple thermal annealing process. The self-healing is attributed to recombination of mobile carbon adatoms with vacancies. With increasing level of plasma induced damage, the self-healing becomes less effective.

  12. Lead monoxide $\\alpha$-PbO: electronic properties and point defect formation

    E-Print Network [OSTI]

    Berashevich, J; Rubel, O; Rowlands, J A; Reznik, A

    2012-01-01

    The electronic properties of polycrystalline lead oxide consisting of a network of single-crystalline $\\alpha$-PbO platelets and the formation of the native point defects in $\\alpha$-PbO crystal lattice are studied using first principles calculations. The $\\alpha$-PbO lattice consists of weakly coupled layers with inter-layer interactions of 0.013 eV/atom that is too low to produce high efficiency charge transfer between the adjacent layers. In practice, the polycrystalline nature of $\\alpha$-PbO causes the formation of lattice defects in such a high concentration that defect-related conductivity becomes the dominant factor in the interlayer charge transition. We found that the formation energy for the O vacancies is low, such vacancies are occupied by two electrons in the zero charge state and tend to donate their electrons to the Pb vacancies that leads to ionization of both vacancies.The vacancies introduce localized states in the band gap which can affect charge transport. The O vacancy forms a defect sta...

  13. Transportation and its Infrastructure

    E-Print Network [OSTI]

    2007-01-01

    gas vehicles Annual road tax differentiated by vintageand charges for road transport Tax/pricing measure Optimalannual circulation taxes, tolls and road charges and parking

  14. Effect of ion mass and charge state on transport of vacuum ARC plasmas through a biased magnetic filter

    E-Print Network [OSTI]

    Byon, Eungsun; Kim, Jong-Kuk; Kwon, Sik-Chol; Anders, Andre

    2003-01-01

    G. Brown, "Transport of vacuum arc plasmas through magneticto rid cathodic arc plasma of macro- and nanoparticles: afrom cathodic arc plasmas," Surf. Coat. Technol. , vol. 133-

  15. Charge transport in zirconium doped anatase nanowires dye-sensitized solar cells: Trade-off between lattice strain and photovoltaic parameters

    SciTech Connect (OSTI)

    Archana, P. S.; Gupta, Arunava; Yusoff, Mashitah M.; Jose, Rajan

    2014-10-13

    Zirconium (Zr) is doped up to 5 at.?% in anatase TiO{sub 2} nanowires by electrospinning and used as working electrode in dye-sensitized solar cells. Variations observed in the photovoltaic parameters were correlated by electrochemical impedance spectroscopy, open circuit voltage decay, and X-ray diffraction measurements. Results show that homovalent substitution of Zr in TiO{sub 2} increased the chemical capacitance and electron diffusion coefficient which in turn decreased charge transport resistance and charge transit time. However, lattice strain due to size mismatch between the Zr{sup 4+} and Ti{sup 4+} ions decreased open circuit voltage and fill factor thereby setting a trade-off between doping concentration and photovoltaic properties.

  16. MESOSCALE DESCRIPTION OF DEFECTED MATERIALS

    E-Print Network [OSTI]

    Vinals, Jorge

    MESOSCALE DESCRIPTION OF DEFECTED MATERIALS Jorge Vi~nals School of Physics and Astronomy. Laughlin) Small but finite wavenumber and finite frequency ("mesoscale") response functions and transport;MESOSCALE DESCRIPTION B B B B B B B A B A B A A B B A A A A BB A B Microscopic Mesoscopic Macroscopic vn

  17. Transportation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout / Transforming Y-12Capacity-Forum Sign InTransportation

  18. Engineering Schottky Contacts in Open-Air Fabricated Heterojunction Solar Cells to Enable High Performance and Ohmic Charge Transport

    E-Print Network [OSTI]

    Hoye, Robert L. Z.; Heffernan, Shane; Ievskaya, Yulia; Sadhanala, Aditya; Flewitt, Andrew; Friend, Richard H.; MacManus-Driscol, Judith L.; Musselman, Kevin P.

    2014-11-24

    surface states27 or (iii) charge tunneling through the Schottky barrier, either directly or via trap states extending below the band-edge of the Zn0.8Mg0.2O. 8,27 Fermi level pinning is unlikely,because there is a large parallel resistance at the Zn0.8Mg0... via a tunneling process may be possible if there exists a sufficiently high density of sub-bandgap states in the Schottky barrier depletion width that electrons can tunnel (hop) between. Accordingly, absorption measurements of Zn0.8Mg0.2O (depos- ited...

  19. Mechanism of Proton Transport in Proton Exchange Membranes: Insights from Computer Simulation

    SciTech Connect (OSTI)

    Gregory A. Voth

    2010-11-30

    The solvation and transport of hydrated protons in proton exchange membranes (PEMs) such as NafionTM will be described using a novel multi-state reactive molecular dynamics (MD) approach, combined with large scale MD simulation to help probe various PEM morphological models. The multi-state MD methodology allows for the treatment of explicit (Grotthuss) proton shuttling and charge defect delocalization which, in turn, can strongly influence the properties of the hydrated protons in various aqueous and complex environments. A significant extension of the methodology to treat highly acidic (low pH) environments such as the hydrophilic domains of a PEM will be presented. Recent results for proton solvation and transport in NafionTM will be described which reveal the significant role of Grotthuss shuttling and charge defect delocalization on the excess proton solvation structures and transport properties. The role of PEM hydration level and morphology on these properties will also be described.

  20. Decoherence and Energy Relaxation in the Quantum-Classical Dynamics for Charge Transport in Organic Semiconducting Crystals: an Instantaneous Decoherence Correction Approach

    E-Print Network [OSTI]

    Si, Wei

    2015-01-01

    We explore an instantaneous decoherence correction (IDC) approach for the decoherence and energy relaxation in the quantum-classical dynamics of charge transport in organic semiconducting crystals. These effects, originating from environmental fluctuations, are essential ingredients of the carrier dynamics. The IDC is carried out by measurement-like operations in the adiabatic representation. While decoherence is inherent in the IDC, energy relaxation is taken into account by considering the detailed balance through the introduction of energy-dependent reweighing factors, which could be either Boltzmann (IDC-BM) or Miller-Abrahams (IDC-MA) type. For a non-diagonal electron-phonon coupling model, it is shown that the IDC tends to enhance diffusion while energy relaxation weakens this enhancement. As expected, both the IDC-BM and IDC-MA achieve a near-equilibrium distribution at finite temperatures in the diffusion process, while the Ehrenfest dynamics renders system tending to infinite temperature limit. The r...

  1. Charge detection in semiconductor nanostructures

    E-Print Network [OSTI]

    MacLean, Kenneth (Kenneth MacLean, III)

    2010-01-01

    In this thesis nanometer scale charge sensors are used to study charge transport in two solid state systems: Lateral GaAs quantum dots and hydrogenated amorphous silicon (a-Si:H). In both of these experiments we use ...

  2. Research on defects and transport in amorphous-silicon-based semiconductors. Final subcontract report, 20 February 1991--19 April 1994

    SciTech Connect (OSTI)

    Schiff, E.A.; Antoniadis, H.; Gu, Q.; Lee, J.K.; Wang, Q.; Zafar, S. [Syracuse Univ., NY (United States)

    1994-09-01

    This report describes work on three individual tasks as follows. (1) Electron and hole drift measurements in a-Si{sub 1-x}Ge{sub x}:H and a-Si{sub 1-x}C{sub x}:H p-i-n solar cells. Multijunction solar cells incorporating modified band gap a-Si:H in a triple-junction structure are generally viewed as the most promising avenue for achieving an amorphous silicon-based solar call with 15% stabilized conversion efficiency. The specific objective of this task was to document the mobilities and deep-trapping mobility-lifetime products for electrons and holes in a-Si{sub 1-x}Ge{sub x}:H and a-Si{sub 1-x}C{sub x}:H alloys materials. (2) Electroabsorption measurements and built-in potential (V{sub bi}) in solar cells. V{sub bi} in a p-i-n solar call may be limiting the open-circuit voltage (V{sub oc}) in wide-band-gap cells (E{sub g} > 1.8 eV) currently under investigation as the top cell for 15% triple junction devices. The research addressed four issues that need to be resolved before the method can yield an error less than 0.1 V for V{sub bi}. The details are presented in this report. (3) Defect relaxation and Shockley-Read kinetics in a-Si:H. Quantitative modeling of solar cells is usually based on Shockley-Read kinetics.`` An important assumption of this approach is that the rate of emission of a photocarrier trapped on a defect is independent of quasi-Fermi level location.

  3. Transport and charging mechanisms in Ta{sub 2}O{sub 5} thin films for capacitive RF MEMS switches application

    SciTech Connect (OSTI)

    Persano, A.; Quaranta, F.; Martucci, M. C.; Creti, P.; Siciliano, P.; Cola, A. [IMM-CNR, Institute for Microelectronics and Microsystems-Unit of Lecce, National Council of Research, Via Monteroni, I-73100 Lecce (Italy)

    2010-06-15

    The potential of sputtered Ta{sub 2}O{sub 5} thin films to be used as dielectric layers in capacitive radio frequency microelectromechanical system switches is evaluated by investigating two factors of crucial importance for the performance of these devices which are the transport mechanisms and the charging effects in the dielectric layer. We find that Ta{sub 2}O{sub 5} films show good electrical and dielectrical properties for the considered application in terms of a low leakage current density of 4 nA/cm{sup 2} for E=1 MV/cm, a high breakdown field of 4 MV/cm and a high dielectric constant of 32. For electric fields lower than 1 MV/cm the conduction mechanism is found to be variable-range hopping in the temperature range 300-400 K, while nearest-neighbor hopping is observed at higher temperatures. For fields in the range 1-4 MV/cm Poole-Frenkel becomes the dominant conduction mechanism. Current and capacitance transients used to investigate the charging effects show a decay which is well described by the stretched-exponential law, thus providing further insights on capture and emission processes.

  4. Two-color optical technique for characterization of x-ray radiation-enhanced electron transport in SiO2

    E-Print Network [OSTI]

    Pantelides, Sokrates T.

    facilitating enhanced electron tunneling through the oxide. The possible nature of the radiation Carrier movement injection, transport, tunneling, and recombination and charge trapping in gate oxides-induced leakage current SILC has been attributed to neutral oxide defects, which mediate electron tunneling across

  5. International aeronautical user charges

    E-Print Network [OSTI]

    Odoni, Amedeo R.

    1985-01-01

    Introduction: 1.1 BACKGROUND AND MOTIVATION Very few issues relating to the international air transportation industry are today as divisive as those pertaining to user charges imposed at international airports and enroute ...

  6. Charge transfer and mobility enhancement at CdO/SnTe heterointerfaces

    SciTech Connect (OSTI)

    Nishitani, Junichi; Yu, Kin Man; Walukiewicz, Wladek

    2014-09-29

    We report a study of the effects of charge transfer on electrical properties of CdO/SnTe heterostructures. A series of structures with variable SnTe thicknesses were deposited by RF magnetron sputtering. Because of an extreme type III band offset with the valence band edge of SnTe located at 1.5?eV above the conduction band edge of CdO, a large charge transfer is expected at the interface of the CdO/SnTe heterostructure. The electrical properties of the heterostructures are analyzed using a multilayer charge transport model. The analysis indicates a large 4-fold enhancement of the CdO electron mobility at the interface with SnTe. The mobility enhancement is attributed to reduction of the charge center scattering through neutralization of the donor-like defects responsible for the Fermi level pinning at the CdO/SnTe interface.

  7. Non-contact Nondestructive Probing of Charge Carrier Conductivity...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    charge carrier transport processes at interfaces is one of the most important subjects in organic electronics. Charge carriers are injected or extracted through metal...

  8. Implications of Permeation through Intrinsic Defects in Graphene on the Design of Defect-Tolerant Membranes for Gas Separation

    E-Print Network [OSTI]

    Sun, Chengzhen

    Gas transport through intrinsic defects and tears is a critical yet poorly understood phenomenon in graphene membranes for gas separation. We report that independent stacking of graphene layers on a porous support exponentially ...

  9. Thermodynamic stability of oxygen point defects in cubic Zirconia

    E-Print Network [OSTI]

    Samanta, Amit; Li, Ju

    2010-01-01

    Zirconia (ZrO2) is an important material with technological applications which are affected by point defect physics. Ab-initio calculations are performed to understand the structural and electronic properties of oxygen vacancies and interstitials in different charge states in cubic zirconia. We find oxygen interstitials in cubic ZrO2 can have five different configurations - dumbbell, dumbbell, crowd-ion, octahedral, and distorted dumbbell. For a neutral and singly charged oxygen interstitial, the lowest energy configuration is the dumbbell, while for a doubly charged oxygen interstitial the octahedral site is energetically the most favorable. Both the oxygen interstitial and the oxygen vacancy are negative-U, so that the singly charged defects are unstable at any Fermi level. The thermodynamic stability of these defects are studied in terms of Fermi level, oxygen partial pressure and temperature. A method to determine the chemical potential of the system as a function of temperature and pressure is propo...

  10. A New Charge Transporting Host Material for Short Wavelength Organic Electrophosphorescence: 2,7Bis(diphenylphosphine oxide)9,9dimethylfluorene

    SciTech Connect (OSTI)

    Padmaperuma, Asanga B.; Sapochak, Linda S.; Burrows, Paul E.

    2006-05-01

    We report the synthesis, crystal structure, photophysical and electroluminescent properties of a new charge transporting host material for short wavelength phosphor-doped organic light emitting devices (OLEDs) based on 2,7-bis(diphenylphosphine oxide)-9,9-dimethylfluorene (PO6). The P=O moiety is used as a point of saturation between the fluorene bridge and outer phenyl groups so that the triplet exciton energy of PO6 is 2.72 eV, similar to that of a dibromo substituted fluorene, but it is more amenable to vacuum sublimation and has good film forming properties. Computational analysis (B3LYP/6-31G*) predicts the HOMO and LUMO energies of PO6 to be lower by 1.5 eV and 0.59 eV, respectively, compared to a similar diphenylamino substituted derivative. In a simple bilayer OLED device, PO6 exhibits structured UV electroluminescence (EL) at a peak wavelength of 335 nm and structured lower energy emission with peaks at 380 nm and 397 nm, similar to the solid film and crystalline solid photoluminescence spectra. The longer wavelength peaks are attributed to aggregate formation via strong intermolecular interactions (P-O---H-C and edge-to-face C-H---??contacts?) and longer range electrostatic interactions between P=O moieties leading to ordered regions in the film. Devices incorporating PO6 as the host material doped with iridium(III)bis(4,6-(di-fluorophenyl)-pyridinato-N,C2.)picolinate (FIrpic) exhibited sky blue emission with peak external quantum efficiency (?ext,max) of 8.1 % and luminous power efficiency (?p,max) of 25.3 lm/W. At a brightness of 800 cd/m2, generally considered to be sufficient for lighting applications, the ?ext and ?p are 6.7 % and 11.8 lm/W and the operating voltage is 5.6 V, which is significantly lower than has been demonstrated previously using this dopant.

  11. Imaging space charge regions in Sm-doped ceria using electrochemical strain microscopy

    SciTech Connect (OSTI)

    Chen, Qian Nataly; Li, Jiangyu; Adler, Stuart B.

    2014-11-17

    Nanocrystalline ceria exhibits a total conductivity several orders of magnitude higher than microcrystalline ceria in air at high temperature. The most widely accepted theory for this enhancement (based on fitting of conductivity data to various transport and kinetic models) is that relatively immobile positively charged defects and/or impurities accumulate at the grain boundary core, leading to a counterbalancing increase in the number of mobile electrons (small polarons) within a diffuse space charge region adjacent to each grain boundary. In an effort to validate this model, we have applied electrochemical strain microscopy to image the location and relative population of mobile electrons near grain boundaries in polycrystalline Sm-doped ceria in air at 20200?C. Our results show the first direct (spatially resolved) evidence that such a diffuse space charge region does exist in ceria, and is localized to both grain boundaries and the gas-exposed surface.

  12. Elastic interactions between 2D geometric defects

    E-Print Network [OSTI]

    Michael Moshe; Eran Sharon; Raz Kupferman

    2015-10-13

    In this paper, we introduce a methodology applicable to a wide range of localized two-dimensional sources of stress. This methodology is based on a geometric formulation of elasticity. Localized sources of stress are viewed as singular defects---point charges of the curvature associated with a reference metric. The stress field in the presence of defects can be solved using a scalar stress function that generalizes the classical Airy stress function to the case of materials with nontrivial geometry. This approach allows the calculation of interaction energies between various types of defects. We apply our methodology to two physical systems: shear-induced failure of amorphous materials and the mechanical interaction between contracting cells.

  13. "Multiscale Capabilities for Exploring Transport Phenomena in...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: "Multiscale Capabilities for Exploring Transport Phenomena in Batteries": Ab Initio Calculations on Defective LiFePO4 Citation Details In-Document Search Title:...

  14. Charged Amino Acids (R83, E567, D617, E625, R669, and K678) of CusA Are Required for Metal Ion Transport in the Cus Efflux System

    SciTech Connect (OSTI)

    Su, Chih-Chia; Long, Feng; Lei, Hsiang-Ting; Reddy Bolla, Jani; Do, Sylvia V.; Rajashankar, Kanagalaghatta R.; Yu, Edward W. (Cornell); (Iowa State)

    2012-10-23

    Gram-negative bacteria expel various toxic chemicals via tripartite efflux pumps belonging to the resistance-nodulation-cell division superfamily. These pumps span both the inner and outer membranes of the cell. The three components of these tripartite systems are an inner-membrane, substrate-binding transporter (or pump); a periplasmic membrane fusion protein (or adaptor); and an outer-membrane-anchored channel. These three efflux proteins interact in the periplasmic space to form the three-part complexes. We previously presented the crystal structures of both the inner-membrane transporter CusA and membrane fusion protein CusB of the CusCBA tripartite efflux system from Escherichia coli. We also described the co-crystal structure of the CusBA adaptor-transporter, revealing that the trimeric CusA efflux pump assembles with six CusB protein molecules to form the complex CusB{sub 6}-CusA{sub 3}. We here report three different conformers of the crystal structures of CusBA-Cu(I), suggesting a mechanism on how Cu(I) binding initiates a sequence of conformational transitions in the transport cycle. Genetic analysis and transport assays indicate that charged residues, in addition to the methionine pairs and clusters, are essential for extruding metal ions out of the cell.

  15. Charge Transport in Organic Semiconductors Veaceslav Coropceanu, Jero^me Cornil,, Demetrio A. da Silva Filho, Yoann Olivier, Robert Silbey,# and

    E-Print Network [OSTI]

    Wu, Zhigang

    companies worldwide, such as Sumitomo, DuPont, Solvay, BASF, Ciba, and Merck to name but a few, are now-transfer and charge-transfer processes that take place in -conjugated polymers and oligomers can now be described

  16. Interlayer coupling enhancement in graphene/hexagonal boron nitride heterostructures by intercalated defects or vacancies

    SciTech Connect (OSTI)

    Park, Sohee [Department of Materials Science and Engineering, Seoul National University, Seoul 151-747 (Korea, Republic of)] [Department of Materials Science and Engineering, Seoul National University, Seoul 151-747 (Korea, Republic of); Park, Changwon [Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Kim, Gunn, E-mail: gunnkim@sejong.ac.kr [Department of Physics and Graphene Research Institute, Sejong University, Seoul 143-747 (Korea, Republic of)] [Department of Physics and Graphene Research Institute, Sejong University, Seoul 143-747 (Korea, Republic of)

    2014-04-07

    Hexagonal boron nitride (hBN), a remarkable material with a two-dimensional atomic crystal structure, has the potential to fabricate heterostructures with unusual properties. We perform first-principles calculations to determine whether intercalated metal atoms and vacancies can mediate interfacial coupling and influence the structural and electronic properties of the graphene/hBN heterostructure. Metal impurity atoms (Li, K, Cr, Mn, Co, and Cu), acting as extrinsic defects between the graphene and hBN sheets, produce n-doped graphene. We also consider intrinsic vacancy defects and find that a boron monovacancy in hBN acts as a magnetic dopant for graphene, whereas a nitrogen monovacancy in hBN serves as a nonmagnetic dopant for graphene. In contrast, the smallest triangular vacancy defects in hBN are unlikely to result in significant changes in the electronic transport of graphene. Our findings reveal that a hBN layer with some vacancies or metal impurities enhances the interlayer coupling in the graphene/hBN heterostructure with respect to charge doping and electron scattering.

  17. Pipeline charging of coke ovens with a preheated charge

    SciTech Connect (OSTI)

    Karpov, A.V.; Khadzhioglo, A.V.; Kuznichenko, V.M.

    1983-01-01

    Work to test a pipeline charging method was conducted at the Konetsk Coke Works (a PK-2K coke oven system with a single gas main, oven width 407 mm, height 4300 mm, effective column 20.0 cm/sub 3/). This method consists of transporting the heated coal charge to the ovens through a pipe by means of steam. the charge is transported by high pressure chamber groups, and loaded by means of systems equipped with devices for separation, withdrawal and treatment of the spent steam. The principal goal of the present investigation was to test technical advances in the emission-free charging of preheated charges. The problem was, first, to create a reliable technology for separation of the steam from the charge immediately before loading it into the oven and, second, to provide a total elimination of emissions, thereby protecting the environment against toxic substances.

  18. Highly Charged Ion (HCI) Modified Tunnel Junctions

    SciTech Connect (OSTI)

    Pomeroy, J. M.; Grube, H. [Atomic Physics Division, National Institute of Standards and Technology (NIST) 100 Bureau Dr., MS 8423, Gaithersburg, MD 20899-8423 (United States)

    2009-03-10

    The neutralization energy carried by highly charged ions (HCIs) provides an alternative method for localizing energy on a target's surface, producing features and modifying surfaces with fluences and kinetic energy damage that are negligible compared to singly ionized atoms. Since each HCI can deposit an enormous amount of energy into a small volume of the surface (e.g., Xe{sup 44+} delivers 51 keV of neutralization energy per HCI), each individual HCI's interaction with the target can produce a nanoscale feature. Many studies of HCI-surface features have characterized some basic principles of this unique ion-surface interaction, but the activity reported here has been focused on studying ensembles of HCI features in ultra-thin insulating films by fabricating multi-layer tunnel junction devices. The ultra-thin insulating barriers allow current to flow by tunneling, providing a very sensitive means of detecting changes in the barrier due to highly charged ion irradiation and, conversely, HCI modification provides a method of finely tuning the transparency of the tunnel junctions that spans several orders of magnitude for devices produced from a single process recipe. Systematic variation of junction bias, temperature, magnetic field and other parameters provides determination of the transport mechanism, defect densities, and magnetic properties of these nano-features and this novel approach to device fabrication.

  19. Net-baryon-, net-proton-, and net-charge kurtosis in heavy-ion collisions within a relativistic transport approach

    E-Print Network [OSTI]

    Marlene Nahrgang; Tim Schuster; Michael Mitrovski; Reinhard Stock; Marcus Bleicher

    2012-09-03

    We explore the potential of net-baryon, net-proton and net-charge kurtosis measurements to investigate the properties of hot and dense matter created in relativistic heavy-ion collisions. Contrary to calculations in a grand canonical ensemble we explicitly take into account exact electric and baryon charge conservation on an event-by-event basis. This drastically limits the width of baryon fluctuations. A simple model to account for this is to assume a grand-canonical distribution with a sharp cut-off at the tails. We present baseline predictions of the energy dependence of the net-baryon, net-proton and net-charge kurtosis for central ($b\\leq 2.75$ fm) Pb+Pb/Au+Au collisions from $E_{lab}=2A$ GeV to $\\sqrt{s_{NN}}=200$ GeV from the UrQMD model. While the net-charge kurtosis is compatible with values around zero, the net-baryon number decreases to large negative values with decreasing beam energy. The net-proton kurtosis becomes only slightly negative for low $\\sqrt{s_{NN}}$.

  20. The thermoelectric properties of molecular junctions can now be investigated with scanning tunnelling microscopy. Such experiments provide insights into charge transport in single

    E-Print Network [OSTI]

    Walsworth, Ronald L.

    The thermoelectric properties of molecular junctions can now be investigated with scanning . They used a scanning tunnelling microscope (STM) to investigate thermoelectricity -- the voltage generated that thermoelectric measurements by STM provide a solution to this problem MOLECULAR ELECTRONICS Charges feel the heat

  1. Graphene materials having randomly distributed two-dimensional structural defects

    DOE Patents [OSTI]

    2013-10-08

    Graphene-based storage materials for high-power battery applications are provided. The storage materials are composed of vertical stacks of graphene sheets and have reduced resistance for Li ion transport. This reduced resistance is achieved by incorporating a random distribution of structural defects into the stacked graphene sheets, whereby the structural defects facilitate the diffusion of Li ions into the interior of the storage materials.

  2. Affine Defects and Gravitation

    E-Print Network [OSTI]

    R. J. Petti

    2014-12-12

    We argue that the structure general relativity (GR) as a theory of affine defects is deeper than the standard interpretation as a metric theory of gravitation. Einstein-Cartan theory (EC), with its inhomogenous affine symmetry, should be the standard-bearer for GR-like theories. A discrete affine interpretation of EC (and gauge theory) yields topological definitions of momentum and spin (and Yang Mills current), and their conservation laws become discrete topological identities. Considerations from quantum theory provide evidence that discrete affine defects are the physical foundation for gravitation.

  3. Mesoscopic pointlike defects in semiconductors: Deep-level energies D. D. Nolte

    E-Print Network [OSTI]

    Nolte, David D.

    Mesoscopic pointlike defects in semiconductors: Deep-level energies D. D. Nolte Department in common with quantum dots, such as Coulomb-charging energies, but unlike quantum dots their electronic properties are dominated by the covalent bond energies of the defect-semiconductor interface. The deep

  4. Motivation Defect correction The algorithm Summary Defect correction in optimization

    E-Print Network [OSTI]

    Hemker, P.W.

    Motivation Defect correction The algorithm Summary Defect correction in optimization "Manifold Mapping" P.W. Hemker IPIR/CWI/UvA June 11, 2010 Manifold Mapping P.W. Hemker #12;Motivation Defect correction The algorithm Summary Motivation Motivation determine x1, x2, x1, x3, x4, x5, x6, x7 Manifold

  5. Defect mapping system

    DOE Patents [OSTI]

    Sopori, B.L.

    1995-04-11

    Apparatus for detecting and mapping defects in the surfaces of polycrystalline materials in a manner that distinguishes dislocation pits from grain boundaries includes a laser for illuminating a wide spot on the surface of the material, a light integrating sphere with apertures for capturing light scattered by etched dislocation pits in an intermediate range away from specular reflection while allowing light scattered by etched grain boundaries in a near range from specular reflection to pass through, and optical detection devices for detecting and measuring intensities of the respective intermediate scattered light and near specular scattered light. A center blocking aperture or filter can be used to screen out specular reflected light, which would be reflected by nondefect portions of the polycrystalline material surface. An X-Y translation stage for mounting the polycrystalline material and signal processing and computer equipment accommodate rastor mapping, recording, and displaying of respective dislocation and grain boundary defect densities. A special etch procedure is included, which prepares the polycrystalline material surface to produce distinguishable intermediate and near specular light scattering in patterns that have statistical relevance to the dislocation and grain boundary defect densities. 20 figures.

  6. Structure, defects, and strain in silicon-silicon oxide interfaces

    SciTech Connect (OSTI)

    Kova?evi?, Goran Pivac, Branko

    2014-01-28

    The structure of the interfaces between silicon and silicon-oxide is responsible for proper functioning of MOSFET devices while defects in the interface can deteriorate this function and lead to their failure. In this paper we modeled this interface and characterized its defects and strain. MD simulations were used for reconstructing interfaces into a thermodynamically stable configuration. In all modeled interfaces, defects were found in the form of three-coordinated silicon atom, five coordinated silicon atom, threefold-coordinated oxygen atom, or displaced oxygen atom. Three-coordinated oxygen atom can be created if dangling bonds on silicon are close enough. The structure and stability of three-coordinated silicon atoms (P{sub b} defect) depend on the charge as well as on the electric field across the interface. The negatively charged P{sub b} defect is the most stable one, but the electric field resulting from the interface reduces that stability. Interfaces with large differences in periodic constants of silicon and silicon oxide can be stabilized by buckling of silicon layer. The mechanical stress resulted from the interface between silicon and silicon oxide is greater in the silicon oxide layer. Ab initio modeling of clusters representing silicon and silicon oxide shows about three time larger susceptibility to strain in silicon oxide than in silicon if exposed to the same deformation.

  7. Infrared photothermal radiometry of deep subsurface defects in semiconductor materials

    E-Print Network [OSTI]

    Mandelis, Andreas

    Infrared photothermal radiometry of deep subsurface defects in semiconductor materials M. E. Rodri sensitivity to the electronic transport properties of the laser photoexcited material.3 Using two information. INTRODUCTION The nondestructive, nonintrusive evaluation of semicon- ductor materials has been of common

  8. Defective graphene as promising anode material for Na-ion battery and Ca-ion battery

    E-Print Network [OSTI]

    Datta, Dibakar; Shenoy, Vivek B

    2013-01-01

    We have investigated adsorption of Na and Ca on graphene with divacancy (DV) and Stone-Wales (SW) defect. Our results show that adsorption is not possible on pristine graphene. However, their adsorption on defective sheet is energetically favorable. The enhanced adsorption can be attributed to the increased charge transfer between adatoms and underlying defective sheet. With the increase in defect density until certain possible limit, maximum percentage of adsorption also increases giving higher battery capacity. For maximum possible DV defect, we can achieve maximum capacity of 1459 mAh/g for Na-ion batteries (NIBs) and 2900 mAh/g for Ca-ion batteries (CIBs). For graphene full of SW defect, we find the maximum capacity of NIBs and CIBs is around 1071 mAh/g and 2142 mAh/g respectively. Our results will help create better anode materials with much higher capacity and better cycling performance for NIBs and CIBs.

  9. Shedding Light on Nanocrystal Defects

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Shedding Light on Nanocrystal Defects Print Nanocrystals have been the focus of much scientific interest lately, given their various advantageous mechanical properties. Their...

  10. Effect of Z{sub 1/2}, EH{sub 5}, and Ci1 deep defects on the performance of n-type 4H-SiC epitaxial layers Schottky detectors: Alpha spectroscopy and deep level transient spectroscopy studies

    SciTech Connect (OSTI)

    Mannan, Mohammad A.; Chaudhuri, Sandeep K.; Nguyen, Khai V.; Mandal, Krishna C.

    2014-06-14

    Spectroscopic performance of Schottky barrier alpha particle detectors fabricated on 50??m thick n-type 4H-SiC epitaxial layers containing Z{sub 1/2}, EH{sub 5}, and Ci1 deep levels were investigated. The device performance was evaluated on the basis of junction current/capacitance characterization and alpha pulse-height spectroscopy. Capacitance mode deep level transient spectroscopy revealed the presence of the above-mentioned deep levels along with two shallow level defects related to titanium impurities (Ti(h) and Ti(c)) and an unidentified deep electron trap located at 2.4?eV below the conduction band minimum, which is being reported for the first time. The concentration of the lifetime killer Z{sub 1/2} defects was found to be 1.7??10{sup 13}?cm{sup ?3}. The charge transport and collection efficiency results obtained from the alpha particle pulse-height spectroscopy were interpreted using a drift-diffusion charge transport model. Based on these investigations, the physics behind the correlation of the detector properties viz., energy resolution and charge collection efficiency, the junction properties like uniformity in barrier-height, leakage current, and effective doping concentration, and the presence of defects has been discussed in details. The studies also revealed that the dominating contribution to the charge collection efficiency was due to the diffusion of charge carriers generated in the neutral region of the detector. The 10 mm{sup 2} large area detectors demonstrated an impressive energy resolution of 1.8% for 5486?keV alpha particles at an optimized operating reverse bias of 130?V.

  11. Intrinsic space charge layers and field enhancement in ferroelectric nanojunctions

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Cao, Ye; Ievlev, Anton V.; Morozovska, Anna N.; Chen, Long-Qing; Kalinin, Sergei V.; Maksymovych, Petro

    2015-07-13

    The conducting characteristics of topological defects in the ferroelectric materials, such as charged domain walls in ferroelectric materials, engendered broad interest and extensive study on their scientific merit and the possibility of novel applications utilizing domain engineering. At the same time, the problem of electron transport in ferroelectrics themselves still remains full of unanswered questions, and becomes still more relevant over the impending revival of interest in ferroelectric semiconductors and new improper ferroelectric materials. We have employed self-consistent phase-field modeling to investigate the physical properties of a local metal-ferroelectric (Pb(Zr0.2Ti0.8)O3) junction in applied electric field. We revealed an up tomore10-fold local field enhancement realized by large polarization gradient and over-polarization effects once the inherent non-linear dielectric properties of PZT are considered. The effect is independent of bias polarity and maintains its strength prior, during and after ferroelectric switching. The local field enhancement can be considered equivalent to increase of doping level, which will give rise to reduction of the switching bias and significantly smaller voltages to charge injection and electronic injection, electrochemical and photoelectrochemical processes.less

  12. Customer loyalty in the public transportation context

    E-Print Network [OSTI]

    Webb, Valerie (Valerie Nichole)

    2010-01-01

    Public transportation agencies, much like other service industries, have a constant churn of their customer base. New customers are entering and current customers are defecting every day. Traditionally, efforts to increase ...

  13. Holographic Chern-Simons Defects

    E-Print Network [OSTI]

    Fujita, Mitsutoshi; Meyer, Rene; Sugimoto, Shigeki

    2016-01-01

    We study SU(N) Yang-Mills-Chern-Simons theory in the presence of defects that shift the Chern-Simons level from a holographic point of view by embedding the system in string theory. The model is a D3-D7 system in Type IIB string theory, whose gravity dual is given by the AdS soliton background with probe D7-branes attaching to the AdS boundary along the defects. We holographically renormalize the free energy of the defect system with sources, from which we obtain the correlation functions for certain operators naturally associated to these defects. We find interesting phase transitions when the separation of the defects as well as the temperature are varied. We also discuss some implications for the Fractional Quantum Hall Effect and for two-dimensional QCD.

  14. Managing Increased Charging Demand

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Managing Increased Charging Demand Carrie Giles ICF International, Supporting the Workplace Charging Challenge Workplace Charging Challenge Do you already own an EV? Are you...

  15. 2010 Defects in Semiconductors GRC

    SciTech Connect (OSTI)

    Shengbai Zhang

    2011-01-06

    Continuing its tradition of excellence, this Gordon Conference will focus on research at the forefront of the field of defects in semiconductors. The conference will have a strong emphasis on the control of defects during growth and processing, as well as an emphasis on the development of novel defect detection methods and first-principles defect theories. Electronic, magnetic, and optical properties of bulk, thin film, and nanoscale semiconductors will be discussed in detail. In contrast to many conferences, which tend to focus on specific semiconductors, this conference will deal with point and extended defects in a broad range of electronic materials. This approach has proved to be extremely fruitful for advancing fundamental understanding in emerging materials such as wide-band-gap semiconductors, oxides, sp{sup 2} carbon based-materials, and photovoltaic/solar cell materials, and in understanding important defect phenomena such as doping bottleneck in nanostructures and the diffusion of defects and impurities. The program consists of about twenty invited talks and a number of contributed poster sessions. The emphasis should be on work which has yet to be published. The large amount of discussion time provides an ideal forum for dealing with topics that are new and/or controversial.

  16. HPSS Charging

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HABFESOpportunitiesNERSCGrid-based29 1.921HEPCharging HPSS Charging

  17. Plug-In Electric Vehicle Handbook for Workplace Charging Hosts

    SciTech Connect (OSTI)

    2013-08-01

    Plug-in electric vehicles (PEVs) have immense potential for increasing the country's energy, economic, and environmental security, and they will play a key role in the future of U.S. transportation. By providing PEV charging at the workplace, employers are perfectly positioned to contribute to and benefit from the electrification of transportation. This handbook answers basic questions about PEVs and charging equipment, helps employers assess whether to offer workplace charging for employees, and outlines important steps for implementation.

  18. Sequential detection of web defects

    DOE Patents [OSTI]

    Eichel, Paul H. (Albuquerque, NM); Sleefe, Gerard E. (Cedar Crest, NM); Stalker, K. Terry (Albuquerque, NM); Yee, Amy A. (Albuquerque, NM)

    2001-01-01

    A system for detecting defects on a moving web having a sequential series of identical frames uses an imaging device to form a real-time camera image of a frame and a comparitor to comparing elements of the camera image with corresponding elements of an image of an exemplar frame. The comparitor provides an acceptable indication if the pair of elements are determined to be statistically identical; and a defective indication if the pair of elements are determined to be statistically not identical. If the pair of elements is neither acceptable nor defective, the comparitor recursively compares the element of said exemplar frame with corresponding elements of other frames on said web until one of the acceptable or defective indications occur.

  19. Kinetic model for electric-field induced point defect redistribution near semiconductor surfaces

    SciTech Connect (OSTI)

    Gorai, Prashun; Seebauer, Edmund G.

    2014-07-14

    The spatial distribution of point defects near semiconductor surfaces affects the efficiency of devices. Near-surface band bending generates electric fields that influence the spatial redistribution of charged mobile defects that exchange infrequently with the lattice, as recently demonstrated for pile-up of isotopic oxygen near rutile TiO{sub 2} (110). The present work derives a mathematical model to describe such redistribution and establishes its temporal dependence on defect injection rate and band bending. The model shows that band bending of only a few meV induces significant redistribution, and that the direction of the electric field governs formation of either a valley or a pile-up.

  20. Nature of Radiation-Induced Defects in Quartz

    E-Print Network [OSTI]

    Bu Wang; Yingtian Yu; Isabella Pignatelli; Gaurav N. Sant; Mathieu Bauchy

    2015-04-10

    Although quartz ($\\rm \\alpha$-form) is a mineral used in numerous applications wherein radiation exposure is an issue, the nature of the atomistic defects formed during radiation-induced damage have not been fully clarified. Especially, the extent of oxygen vacancy formation is still debated, which is an issue of primary importance as optical techniques based on charged oxygen vacancies have been utilized to assess the level of radiation damage in quartz. In this paper, molecular dynamics (MD) simulations are applied to study the effects of ballistic impacts on the atomic network of quartz. We show that the defects that are formed mainly consist of over-coordinated Si and O, as well as Si--O connectivity defects, e.g., small Si--O rings and edge-sharing Si tetrahedra. Oxygen vacancies, on the contrary, are found in relatively low abundance, suggesting that characterizations based on $E^{\\prime}$ centers do not adequately capture radiation-induced structural damage in quartz. Finally, we evaluate the dependence on the incident energy, of the amount of each type of the point defects formed, and quantify unambiguously the threshold displacement energies for both O and Si atoms. These results provide a comprehensive basis to assess the nature and extent of radiation damage in quartz.

  1. Sustainable Transport

    E-Print Network [OSTI]

    Webber, Melvin

    2006-01-01

    THOUGHT PIECE Sustainable Transport by Melvin M. Webberwant to sustain any mode of transport only if we judge it todraconian in rejecting transport modes that have failed in

  2. Intrinsic point-defect equilibria in tetragonal ZrO[subscript 2]: Density functional theory analysis with finite-temperature effects

    E-Print Network [OSTI]

    Youssef, Mostafa Youssef Mahm

    We present a density functional theory (DFT) framework taking into account the finite temperature effects to quantitatively understand and predict charged defect equilibria in a metal oxide. Demonstration of this approach ...

  3. Native defects in MBE-grown CdTe

    SciTech Connect (OSTI)

    Olender, Karolina; Wosinski, Tadeusz; Makosa, Andrzej; Tkaczyk, Zbigniew; Kolkovsky, Valery; Karczewski, Grzegorz

    2013-12-04

    Deep-level traps in both n- and p-type CdTe layers, grown by molecular-beam epitaxy on GaAs substrates, have been investigated by means of deep-level transient spectroscopy (DLTS). Four of the traps revealed in the DLTS spectra, which displayed exponential kinetics for capture of charge carriers into the trap states, have been assigned to native point defects: Cd interstitial, Cd vacancy, Te antisite defect and a complex formed of the Te antisite and Cd vacancy. Three further traps, displaying logarithmic capture kinetics, have been ascribed to electron states of treading dislocations generated at the mismatched interface with the substrate and propagated through the CdTe layer.

  4. Workplace Charging Challenge: Sample Workplace Charging Policy

    Broader source: Energy.gov [DOE]

    Review the policy guidelines used by one Workplace Charging Challenge partner to keep their program running safe and successfully.

  5. Imaging transport resonances in the quantum Hall effect

    E-Print Network [OSTI]

    Steele, Gary Alexander

    2006-01-01

    We image charge transport in the quantum Hall effect using a scanning charge accumulation microscope. Applying a DC bias voltage to the tip induces a highly resistive ring-shaped incompressible strip (IS) in a very high ...

  6. Fluid Neutral Momentum Transport Reference Problem

    E-Print Network [OSTI]

    Budny, Robert

    Fluid Neutral Momentum Transport Reference Problem D. P. Stotler, PPPL S. I. Krasheninnikov, UCSD 1 Summary Type of problem: kinetic or fluid neutral transport Physics or algorithm stressed: thermal force term (spatial resolution) in momentum transport equation and treatment of collisions (charge ex- change

  7. An investigation of defect detection using random defect excitation and deterministic defect observation in complex integrated logic circuits

    E-Print Network [OSTI]

    Dworak, Jennifer

    2013-02-22

    aWhenever integrated circuits are manufactured, a certain percentage of those circuits will be defective. Defective circuits present problems for both the manufacturers who wish to maintain a good reputation with their customers and the consumers...

  8. Defects in Crystals Faizan Nazar

    E-Print Network [OSTI]

    Sengun, Mehmet Haluk

    that are close to the defect. Figure : A 2D sketch of a perfect lattice and a lattice which has been re researchers are also into looking into new materials like graphene), but manufacturers also introduce. The new material is called a semiconductor. There are two types of doping, called p-type and n-type, short

  9. Electric Vehicle Workplace Charging

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    or Twitter Attend local EV events Share your story Currently have 13 ChargePoint charging stations scattered throughout Vermont 2015 - 12 Freedom Stations & 10...

  10. Workplace Charging Challenge

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    EV Everywhere Workplace Charging Challenge, committing to install charging for plug-in electric vehicles (PEVs) at their worksites. By taking on this Challenge, they are helping...

  11. Workplace Charging Challenge

    SciTech Connect (OSTI)

    2013-09-01

    Fact sheet about the EV Everywhere Workplace Charging Challenge which is to increase the number of American employers offering workplace charging by tenfold in the next five years.

  12. Theory of water and charged liquid bridges

    E-Print Network [OSTI]

    Klaus Morawetz

    2012-05-29

    The phenomena of liquid bridge formation due to an applied electric field is investigated. A new solution for the charged catenary is presented which allows to determine the static and dynamical stability conditions where charged liquid bridges are possible. The creeping height, the bridge radius and length as well as the shape of the bridge is calculated showing an asymmetric profile in agreement with observations. The flow profile is calculated from the Navier Stokes equation leading to a mean velocity which combines charge transport with neutral mass flow and which describes recent experiments on water bridges.

  13. Multiscale Defect Formation and Transport in Materials in Extreme Environments

    E-Print Network [OSTI]

    Seif, Dariush

    2013-01-01

    reverse the plasticity, leaving the crystal in its initial,to initiate plasticity in the [111] crystals. We find the

  14. Multiscale Defect Formation and Transport in Materials in Extreme Environments

    E-Print Network [OSTI]

    Seif, Dariush

    2013-01-01

    damage rate. G H Helium production rate. C s i Equivalentdue to the chosen helium production rate (5 appm/dpa). Thisproduction of significant quantities of so- lute atoms within the bulk, namely helium and

  15. Charging Graphene for Energy Storage

    SciTech Connect (OSTI)

    Liu, Jun

    2014-10-06

    Since 2004, graphene, including single atomic layer graphite sheet, and chemically derived graphene sheets, has captured the imagination of researchers for energy storage because of the extremely high surface area (2630 m2/g) compared to traditional activated carbon (typically below 1500 m2/g), excellent electrical conductivity, high mechanical strength, and potential for low cost manufacturing. These properties are very desirable for achieving high activity, high capacity and energy density, and fast charge and discharge. Chemically derived graphene sheets are prepared by oxidation and reduction of graphite1 and are more suitable for energy storage because they can be made in large quantities. They still contain multiply stacked graphene sheets, structural defects such as vacancies, and oxygen containing functional groups. In the literature they are also called reduced graphene oxide, or functionalized graphene sheets, but in this article they are all referred to as graphene for easy of discussion. Two important applications, batteries and electrochemical capacitors, have been widely investigated. In a battery material, the redox reaction occurs at a constant potential (voltage) and the energy is stored in the bulk. Therefore, the energy density is high (more than 100 Wh/kg), but it is difficult to rapidly charge or discharge (low power, less than 1 kW/kg)2. In an electrochemical capacitor (also called supercapacitors or ultracapacitor in the literature), the energy is stored as absorbed ionic species at the interface between the high surface area carbon and the electrolyte, and the potential is a continuous function of the state-of-charge. The charge and discharge can happen rapidly (high power, up to 10 kW/kg) but the energy density is low, less than 10 Wh/kg2. A device that can have both high energy and high power would be ideal.

  16. Fact #747: October 1, 2012 Behind Housing, Transportation is...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    transportation in a year than on food. Vehicle purchases, along with gasoline and motor oil, make up a large part of vehicle expenditures, but insurance, finance charges,...

  17. Inspection of lithographic mask blanks for defects

    DOE Patents [OSTI]

    Sommargren, Gary E. (Santa Cruz, CA)

    2001-01-01

    A visible light method for detecting sub-100 nm size defects on mask blanks used for lithography. By using optical heterodyne techniques, detection of the scattered light can be significantly enhanced as compared to standard intensity detection methods. The invention is useful in the inspection of super-polished surfaces for isolated surface defects or particulate contamination and in the inspection of lithographic mask or reticle blanks for surface defects or bulk defects or for surface particulate contamination.

  18. Optical method and apparatus for detection of surface and near-subsurface defects in dense ceramics

    DOE Patents [OSTI]

    Ellingson, W.A.; Brada, M.P.

    1995-06-20

    A laser is used in a non-destructive manner to detect surface and near-subsurface defects in dense ceramics and particularly in ceramic bodies with complex shapes such as ceramic bearings, turbine blades, races, and the like. The laser`s wavelength is selected based upon the composition of the ceramic sample and the laser can be directed on the sample while the sample is static or in dynamic rotate or translate motion. Light is scattered off surface and subsurface defects using a preselected polarization. The change in polarization angle is used to select the depth and characteristics of surface/subsurface defects. The scattered light is detected by an optical train consisting of a charge coupled device (CCD), or vidicon, television camera which, in turn, is coupled to a video monitor and a computer for digitizing the image. An analyzing polarizer in the optical train allows scattered light at a given polarization angle to be observed for enhancing sensitivity to either surface or near-subsurface defects. Application of digital image processing allows subtraction of digitized images in near real-time providing enhanced sensitivity to subsurface defects. Storing known ``feature masks`` of identified defects in the computer and comparing the detected scatter pattern (Fourier images) with the stored feature masks allows for automatic classification of detected defects. 29 figs.

  19. Optical method and apparatus for detection of surface and near-subsurface defects in dense ceramics

    DOE Patents [OSTI]

    Ellingson, William A. (Naperville, IL); Brada, Mark P. (Goleta, CA)

    1995-01-01

    A laser is used in a non-destructive manner to detect surface and near-subsurface defects in dense ceramics and particularly in ceramic bodies with complex shapes such as ceramic bearings, turbine blades, races, and the like. The laser's wavelength is selected based upon the composition of the ceramic sample and the laser can be directed on the sample while the sample is static or in dynamic rotate or translate motion. Light is scattered off surface and subsurface defects using a preselected polarization. The change in polarization angle is used to select the depth and characteristics of surface/subsurface defects. The scattered light is detected by an optical train consisting of a charge coupled device (CCD), or vidicon, television camera which, in turn, is coupled to a video monitor and a computer for digitizing the image. An analyzing polarizer in the optical train allows scattered light at a given polarization angle to be observed for enhancing sensitivity to either surface or near-subsurface defects. Application of digital image processing allows subtraction of digitized images in near real-time providing enhanced sensitivity to subsurface defects. Storing known "feature masks" of identified defects in the computer and comparing the detected scatter pattern (Fourier images) with the stored feature masks allows for automatic classification of detected defects.

  20. Screening method for selecting semiconductor substrates having defects below a predetermined level in an oxide layer

    DOE Patents [OSTI]

    Warren, W.L.; Vanheusden, K.J.R.; Schwank, J.R.; Fleetwood, D.M.; Shaneyfelt, M.R.; Winokur, P.S.; Devine, R.A.B.

    1998-07-28

    A method is disclosed for screening or qualifying semiconductor substrates for integrated circuit fabrication. The method comprises the steps of annealing at least one semiconductor substrate at a first temperature in a defect-activating ambient (e.g. hydrogen, forming gas, or ammonia) for sufficient time for activating any defects within on oxide layer of the substrate; measuring a defect-revealing electrical characteristic of at least a portion of the oxide layer for determining a quantity of activated defects therein; and selecting substrates for which the quantity of activated defects is below a predetermined level. The defect-revealing electrical characteristic may be a capacitance-versus voltage (C-V) characteristic or a current-versus-voltage (I-V) characteristic that is dependent on an electrical charge in the oxide layer generated by the activated defects. Embodiments of the present invention may be applied for screening any type of semiconductor substrate or wafer having an oxide layer formed thereon or therein. This includes silicon-on-insulator substrates formed by a separation by the implantation of oxygen (SIMOX) process or the bond and etch back silicon-on-insulator (BESOI) process, as well as silicon substrates having a thermal oxide layer or a deposited oxide layer. 5 figs.

  1. Screening method for selecting semiconductor substrates having defects below a predetermined level in an oxide layer

    DOE Patents [OSTI]

    Warren, William L. (Albuquerque, NM); Vanheusden, Karel J. R. (Albuquerque, NM); Schwank, James R. (Albuquerque, NM); Fleetwood, Daniel M. (Albuquerque, NM); Shaneyfelt, Marty R. (Albuquerque, NM); Winokur, Peter S. (Albuquerque, NM); Devine, Roderick A. B. (St. Martin le Vinoux, FR)

    1998-01-01

    A method for screening or qualifying semiconductor substrates for integrated circuit fabrication. The method comprises the steps of annealing at least one semiconductor substrate at a first temperature in a defect-activating ambient (e.g. hydrogen, forming gas, or ammonia) for sufficient time for activating any defects within on oxide layer of the substrate; measuring a defect-revealing electrical characteristic of at least a portion of the oxide layer for determining a quantity of activated defects therein; and selecting substrates for which the quantity of activated defects is below a predetermined level. The defect-revealing electrical characteristic may be a capacitance-versus-voltage (C-V) characteristic or a current-versus-voltage (I-V) characteristic that is dependent on an electrical charge in the oxide layer generated by the activated defects. Embodiments of the present invention may be applied for screening any type of semiconductor substrate or wafer having an oxide layer formed thereon or therein. This includes silicon-on-insulator substrates formed by a separation by the implantation of oxygen (SIMOX) process or the bond and etch back silicon-on-insulator (BESOI) process, as well as silicon substrates having a thermal oxide layer or a deposited oxide layer.

  2. Tracking Defect Warnings Across Versions Jaime Spacco

    E-Print Network [OSTI]

    Hovemeyer, David H.

    the results of tracking defect warnings across Sun's Java runtime library. Categories and Subject DescriptorsTracking Defect Warnings Across Versions Jaime Spacco , David Hovemeyer , William Pugh Dept of reasons, it is important to be able to track the occurrence of each potential defect over multiple

  3. Optics near an hyperbolic defect

    E-Print Network [OSTI]

    Fumeron, Sbastien; Santos, Fernando; Pereira, Erms; Moraes, Fernando

    2015-01-01

    We examine the properties of a new family of defects called hyperbolic disclinations, and discuss their possible use for the design of perfect optical absorbers. In hyperbolic metamaterials, the ratio of ordinary and extraordinary permittivities is negative, which leads to an effective metric of Kleinian signature (two timelike coordinates). Considering a disclination in the hyperbolic nematic host matrix, we show that the timelike geodesics are Poinsot spirals, i.e. whatever the impact parameter of an incident light beam, it is confined and whirls about the defect core. The trapping effect does not require light to be coherent. This property also remains in the wave formalism, which may be the sign for many potential applications.

  4. Effects of Stone-Wales and vacancy defects in atomic-scale friction on defective graphite

    SciTech Connect (OSTI)

    Sun, Xiao-Yu; Wu, RunNi; Xia, Re; Chu, Xi-Hua; Xu, Yuan-Jie

    2014-05-05

    Graphite is an excellent solid lubricant for surface coating, but its performance is significantly weakened by the vacancy or Stone-Wales (SW) defect. This study uses molecular dynamics simulations to explore the frictional behavior of a diamond tip sliding over a graphite which contains a single defect or stacked defects. Our results suggest that the friction on defective graphite shows a strong dependence on defect location and type. The 5-7-7-5 structure of SW defect results in an effectively negative slope of friction. For defective graphite containing a defect in the surface, adding a single vacancy in the interior layer will decrease the friction coefficients, while setting a SW defect in the interior layer may increase the friction coefficients. Our obtained results may provide useful information for understanding the atomic-scale friction properties of defective graphite.

  5. Space Charge Correction on Emittance Measurement of Low Energy...

    Office of Scientific and Technical Information (OSTI)

    of Low Energy Electron Beams The goal of any particle accelerator is to optimize the transport of a charged particle beam along a set path by confining the beam to a small region...

  6. Too expensive to meter: The influence of transaction costs in transportation and

    E-Print Network [OSTI]

    Odlyzko, Andrew M.

    , London Underground, London railways, collection costs, transaction costs, public transport 1Too expensive to meter: The influence of transaction costs in transportation and communication, and that in many cases such charging may lead to undesirable outcomes. Keywords: Transport, Telecommunications

  7. Tuning Interfacial Thermal Conductance of Graphene Embedded in Soft Materials by Vacancy Defects

    SciTech Connect (OSTI)

    Liu, Ying [Clemson University; Hu, Chongze [Clemson University; Huang, Jingsong [ORNL; Sumpter, Bobby G [ORNL; Qiao, Rui [Engineering Science and Mechanics Department, Virginia Tech, Blacksburg, VA, USA

    2015-01-01

    Nanocomposites based on graphene dispersed in matrices of soft materials are promising thermal management materials. Their effective thermal conductivity depends on both the thermal conductivity of graphene and the conductance of the thermal transport across graphene-matrix interfaces. Here we report on molecular dynamics simulations of the thermal transport across the interfaces between defected graphene and soft materials in two different modes: in the across mode, heat enters graphene from one side of its basal plane and leaves through the other side; in the non-across mode, heat enters or leaves a graphene simultaneously from both sides of its basal plane. We show that, as the density of vacancy defects in graphene increases from 0 to 8%, the conductance of the interfacial thermal transport in the across mode increases from 160.4 16 to 207.8 11 MW/m2K, while that in the non-across mode increases from 7.2 0.1 to 17.8 0.6 MW/m2K. The molecular mechanisms for these variations of thermal conductance are clarified by using the phonon density of states and structural characteristics of defected graphenes. On the basis of these results and effective medium theory, we show that it is possible to enhance the effective thermal conductivity of thermal nanocomposites by tuning the density of vacancy defects in graphene despite the fact that graphene s thermal conductivity always decreases as vacancy defects are introduced.

  8. Conformal nets III: fusion of defects

    E-Print Network [OSTI]

    Arthur Bartels; Christopher L. Douglas; Andr Henriques

    2015-02-21

    Conformal nets provides a mathematical model for conformal field theory. We define a notion of defect between conformal nets, formalizing the idea of an interaction between two conformal field theories. We introduce an operation of fusion of defects, and prove that the fusion of two defects is again a defect, provided the fusion occurs over a conformal net of finite index. There is a notion of sector (or bimodule) between two defects, and operations of horizontal and vertical fusion of such sectors. Our most difficult technical result is that the horizontal fusion of the vacuum sectors of two defects is isomorphic to the vacuum sector of the fused defect. Equipped with this isomorphism, we construct the basic interchange isomorphism between the horizontal fusion of two vertical fusions and the vertical fusion of two horizontal fusions of sectors.

  9. Realizing the fusion rules of Ising anyons without lattice defects

    E-Print Network [OSTI]

    Ferreira, Miguel Jorge Bernabe; Teotonio-Sobrinho, Paulo

    2015-01-01

    Topologically ordered phases in two dimensions are characterized by their low energy excitations which are called anyons. These anyons are labeled by a set of anyon labels which can be braided and fused. These fusion and braiding properties can remain invariant under certain permutations of these anyon labels which generate an anyon symmetry group. In the example of the toric code this anyon symmetry manifests itself in the exchange of the charge, $e$ and flux, $m$ particles which is nothing but the electric-magnetic duality of the toric code model of Kitaev. However this is a global symmetry of the theory. It was shown to occur locally by the introduction of lattice defects which in turn induces a change in the toric code Hamiltonian along the defect. Here we introduce an exactly solvable model which achieves the local $e$-$m$ exchange without any modification to the lattice in the form of dislocations. However the Hamiltonian is still changed locally in what we call defect sites.These induce the permutation...

  10. Modelling a CNTFET with Undeposited CNT Defects Geunho Cho, Fabrizio Lombardi, Yong-Bin Kim

    E-Print Network [OSTI]

    Ayers, Joseph

    and manufacturing a CNTFET, additional features such as pitch, number and position of the CNTs must be considered. INDEX TERMS: Defect model, CNT, CNTFET, manufacturing, emerging technologies 1. Introduction The Carbon manufacturing processes. In CNTFETs, ballistic or near-ballistic transport phenomena have been observed under

  11. Congestion control in charging of electric vehicles

    E-Print Network [OSTI]

    Carvalho, Rui; Gibbens, Richard; Kelly, Frank

    2015-01-01

    The increasing penetration of electric vehicles over the coming decades, taken together with the high cost to upgrade local distribution networks, and consumer demand for home charging, suggest that managing congestion on low voltage networks will be a crucial component of the electric vehicle revolution and the move away from fossil fuels in transportation. Here, we model the max-flow and proportional fairness protocols for the control of congestion caused by a fleet of vehicles charging on distribution networks. We analyse the inequality in the charging times as the vehicle arrival rate increases, and show that charging times are considerably more uneven in max-flow than in proportional fairness. We also analyse the onset of instability, and find that the critical arrival rate is indistinguishable between the two protocols.

  12. OXYGEN TRANSPORT CERAMIC MEMBRANES

    SciTech Connect (OSTI)

    Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

    2000-10-01

    This is the third quarterly report on oxygen Transport Ceramic Membranes. In the following, the report describes the progress made by our university partners in Tasks 1 through 6, experimental apparatus that was designed and built for various tasks of this project, thermodynamic calculations, where applicable and work planned for the future. (Task 1) Design, fabricate and evaluate ceramic to metal seals based on graded ceramic powder/metal braze joints. (Task 2) Evaluate the effect of defect configuration on ceramic membrane conductivity and long term chemical and structural stability. (Task 3) Determine materials mechanical properties under conditions of high temperatures and reactive atmospheres. (Task 4) Evaluate phase stability and thermal expansion of candidate perovskite membranes and develop techniques to support these materials on porous metal structures. (Task 5) Assess the microstructure of membrane materials to evaluate the effects of vacancy-impurity association, defect clusters, and vacancy-dopant association on the membrane performance and stability. (Task 6) Measure kinetics of oxygen uptake and transport in ceramic membrane materials under commercially relevant conditions using isotope labeling techniques.

  13. Charge regulation circuit

    DOE Patents [OSTI]

    Ball, Don G. (Livermore, CA)

    1992-01-01

    A charge regulation circuit provides regulation of an unregulated voltage supply in the range of 0.01%. The charge regulation circuit is utilized in a preferred embodiment in providing regulated voltage for controlling the operation of a laser.

  14. Workplace Charging Challenge

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    corporate leadership and innovation, demonstrating a willingness to adopt advanced technology. Sustainability Providing PEV charging can enhance corporate sustainability efforts,...

  15. Charge exchange system

    DOE Patents [OSTI]

    Anderson, Oscar A. (Berkeley, CA)

    1978-01-01

    An improved charge exchange system for substantially reducing pumping requirements of excess gas in a controlled thermonuclear reactor high energy neutral beam injector. The charge exchange system utilizes a jet-type blanket which acts simultaneously as the charge exchange medium and as a shield for reflecting excess gas.

  16. Thermite charge - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    & Trademark Office Marketing Summary: Linear Thermite Charge Abstract: The present invention provides for cutting operations using linear thermite charges; the charges cut one...

  17. Electric Vehicle Smart Charging Infrastructure

    E-Print Network [OSTI]

    Chung, Ching-Yen

    2014-01-01

    Management for Urban EV Charging Systems, 2013 IEEEfor Large Scale Public EV Charging Facilities, 2013 IEEESmart Electric Vehicle (EV) Charging and Grid Integration

  18. Electric Vehicle Smart Charging Infrastructure

    E-Print Network [OSTI]

    Chung, Ching-Yen

    2014-01-01

    for Multiplexed Electric Vehicle Charging, US20130154561A1,Chynoweth, Intelligent Electric Vehicle Charging System,of RFID Mesh Network for Electric Vehicle Smart Charging

  19. Electronic Charges and Electric Potential at LaAlO3/SrTiO3 Interfaces Studied by Core-Level Photoemission Spectroscopy

    SciTech Connect (OSTI)

    Hwang, Harold

    2011-08-19

    We studied LaAlO{sub 3}/SrTiO{sub 3} interfaces for varying LaAlO{sub 3} thickness by core-level photoemission spectroscopy. In Ti 2p spectra for conducting 'n-type' interfaces, Ti{sup 3+} signals appeared, which were absent for insulating 'p-type' interfaces. The Ti{sup 3+} signals increased with LaAlO{sub 3} thickness, but started well below the critical thickness of 4 unit cells for metallic transport. Core-level shifts with LaAlO{sub 3} thickness were much smaller than predicted by the polar catastrophe model. We attribute these observations to surface defects/adsorbates providing charges to the interface even below the critical thickness.

  20. Non-Tracial Free Transport and Applications

    E-Print Network [OSTI]

    Nelson, Brent Andrew

    2015-01-01

    tracial transport . . . . . . . . . . . . . . . . . . . .the transport element . . . . . . . . . . . . . .Free Transport . . . . . . . . . . . .

  1. Workplace Charging Challenge Progress Update 2014: Employers...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Workplace Charging Challenge Progress Update 2014: Employers Take Charge Workplace Charging Challenge Progress Update 2014: Employers Take Charge The Workplace Charging Challenge...

  2. Environment Assisted Quantum Transport in Organic Molecules

    E-Print Network [OSTI]

    Vattay, Gabor

    2015-01-01

    One of the new discoveries in quantum biology is the role of Environment Assisted Quantum Transport (ENAQT) in excitonic transport processes. In disordered quantum systems transport is most efficient when the environment just destroys quantum interferences responsible for localization, but the coupling does not drive the system to fully classical thermal diffusion yet. This poised realm between the pure quantum and the semi-classical domains has not been considered in other biological transport processes, such as charge transport through organic molecules. Binding in receptor-ligand complexes is assumed to be static as electrons are assumed to be not able to cross the ligand molecule. We show that ENAQT makes cross ligand transport possible and efficient between certain atoms opening the way for the reorganization of the charge distribution on the receptor when the ligand molecule docks. This new effect can potentially change our understanding how receptors work. We demonstrate room temperature ENAQT on the c...

  3. Asymmetric Electron Transport at Monolayer-Bilayer Heterojunctions of Epitaxial Graphene

    SciTech Connect (OSTI)

    Li, An-Ping [ORNL] [ORNL; Clark, Kendal W [ORNL] [ORNL; Zhang, Xiaoguang [ORNL] [ORNL; Gu, Gong [University of Tennessee, Knoxville (UTK)] [University of Tennessee, Knoxville (UTK); He, Guowei [Carnegie Mellon University (CMU)] [Carnegie Mellon University (CMU); Feenstra, Randall [Carnegie Mellon University (CMU)] [Carnegie Mellon University (CMU)

    2014-01-01

    The symmetry of the graphene honeycomb lattice is a key element determining many of graphene s unique electronic properties, such as the linear energy-momentum dispersion and the suppressed backscattering 1,2. However, line defects in large-scale epitaxial graphene films, such as grain boundaries, edges, surface steps, and changes in layer thickness, often break the sublatttice symmetry and can impact transport properties of graphene profoundly 3-6. Here we report asymmetric electron transport upon polarity reversal at individual monolayer-bilayer (ML-BL) boundaries in epitaxial graphene on SiC (0001), revealed by scanning tunneling potentiometry. A greater voltage drop is observed when the current flows from BL to ML graphene than in the reverse direction, and the difference remains nearly unchanged with increasing current. This is not a typical nonlinear conductance due to electron transmission through an asymmetric potential. Rather, it indicates the opening of a dynamic energy gap at the Fermi energy due to the Coulomb interaction between the injected nonequilibrium electron density and the pseudospin polarized Friedel oscillation charge density at the boundary. This intriguing heterojunction transport behavior opens a new avenue towards novel quantum functions such as quantum switching.

  4. Simulation of localized barrier defects in resonant tunneling diodes

    E-Print Network [OSTI]

    Stoneberg, Jason Neal

    1995-01-01

    defect assisted tunneling as a possible current mechanism. This study attempts to ascertain the effects of defect potentials in the barriers on current in a simulation of a double barrier resonant tunneling diode. Results indicate that these defects could...

  5. Automakers and Workplace Charging

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Challenge Initiative Arguably the most important infrastructure strategy to accelerate adoption of PEVs. Why are we doing Workplace Charging? * PEV Market Growth - Critical now...

  6. Nonlinear space charge dynamics in mixed ionic-electronic conductors: Resistive switching and ferroelectric-like hysteresis of electromechanical response

    SciTech Connect (OSTI)

    Morozovska, Anna N.; Morozovsky, Nicholas V.; Eliseev, Eugene A.; Varenyk, Olexandr V.; Kim, Yunseok; Strelcov, Evgheni; Tselev, Alexander; Kalinin, Sergei V.

    2014-08-14

    We performed self-consistent modelling of nonlinear electrotransport and electromechanical response of thin films of mixed ionic-electronic conductors (MIEC) allowing for steric effects of mobile charged defects (ions, protons, or vacancies), electron degeneration, and Vegard stresses. We establish correlations between the features of the nonlinear space-charge dynamics, current-voltage, and bending-voltage curves for different types of the film electrodes. A pronounced ferroelectric-like hysteresis of the bending-voltage loops and current maxima on the double hysteresis current-voltage loops appear for the electron-transport electrodes. The double hysteresis loop with pronounced humps indicates a memristor-type resistive switching. The switching occurs due to the strong nonlinear coupling between the electronic and ionic subsystems. A sharp meta-stable maximum of the electron density appears near one open electrode and moves to another one during the periodic change of applied voltage. Our results can explain the nonlinear nature and correlation of electrical and mechanical memory effects in thin MIEC films. The analytical expression proving that the electrically induced bending of MIEC films can be detected by interferometric methods is derived.

  7. Gauge turbulence, topological defect dynamics, and condensation in Higgs models

    SciTech Connect (OSTI)

    Gasenzer, Thomas; McLerran, Larry; Pawlowski, Jan M.; Sexty, Dnes

    2014-07-28

    The real-time dynamics of topological defects and turbulent configurations of gauge fields for electric and magnetic confinement are studied numerically within a 2+1D Abelian Higgs model. It is shown that confinement is appearing in such systems equilibrating after a strong initial quench such as the overpopulation of the infrared modes. While the final equilibrium state does not support confinement, metastable vortex defect configurations appearing in the gauge field are found to be closely related to the appearance of physically observable confined electric and magnetic charges. These phenomena are seen to be intimately related to the approach of a non-thermal fixed point of the far-from-equilibrium dynamical evolution, signaled by universal scaling in the gauge-invariant correlation function of the Higgs field. Even when the parameters of the Higgs action do not support condensate formation in the vacuum, during this approach, transient Higgs condensation is observed. We discuss implications of these results for the far-from-equilibrium dynamics of YangMills fields and potential mechanisms of how confinement and condensation in non-Abelian gauge fields can be understood in terms of the dynamics of Higgs models. These suggest that there is an interesting new class of dynamics of strong coherent turbulent gauge fields with condensates.

  8. Gauge turbulence, topological defect dynamics, and condensation in Higgs models

    SciTech Connect (OSTI)

    Gasenzer, Thomas [Heidelberg Univ. (Germany). Inst. for Theoretische Physik; GSI-Darmstadt (Germany). ExtreMe Matter Inst. (EMMI); McLerran, Larry [Brookhaven National Lab. (BNL), Upton, NY (United States). RIKEN Research Center and Physics Dept.; China Central Normal Univ., Wuhan (China). Physics Dept.; Pawlowski, Jan M. [Heidelberg Univ. (Germany). Inst. for Theoretische Physik; GSI-Darmstadt (Germany). ExtreMe Matter Inst. (EMMI); Sexty, Dnes [Heidelberg Univ. (Germany). Inst. for Theoretische Physik; GSI-Darmstadt (Germany). ExtreMe Matter Inst. (EMMI)

    2014-10-01

    The real-time dynamics of topological defects and turbulent configurations of gauge fields for electric and magnetic confinement are studied numerically within a 2+1D Abelian Higgs model. It is shown that confinement is appearing in such systems equilibrating after a strong initial quench such as the overpopulation of the infrared modes. While the final equilibrium state does not support confinement, metastable vortex defect configurations appearing in the gauge field are found to be closely related to the appearance of physically observable confined electric and magnetic charges. These phenomena are seen to be intimately related to the approach of a non-thermal fixed point of the far-from-equilibrium dynamical evolution, signaled by universal scaling in the gauge-invariant correlation function of the Higgs field. Even when the parameters of the Higgs action do not support condensate formation in the vacuum, during this approach, transient Higgs condensation is observed. We discuss implications of these results for the far-from-equilibrium dynamics of YangMills fields and potential mechanisms of how confinement and condensation in non-Abelian gauge fields can be understood in terms of the dynamics of Higgs models. These suggest that there is an interesting new class of dynamics of strong coherent turbulent gauge fields with condensates.

  9. Gauge turbulence, topological defect dynamics, and condensation in Higgs models

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gasenzer, Thomas; McLerran, Larry; Pawlowski, Jan M.; Sexty, Dnes

    2014-07-28

    The real-time dynamics of topological defects and turbulent configurations of gauge fields for electric and magnetic confinement are studied numerically within a 2+1D Abelian Higgs model. It is shown that confinement is appearing in such systems equilibrating after a strong initial quench such as the overpopulation of the infrared modes. While the final equilibrium state does not support confinement, metastable vortex defect configurations appearing in the gauge field are found to be closely related to the appearance of physically observable confined electric and magnetic charges. These phenomena are seen to be intimately related to the approach of a non-thermal fixedmorepoint of the far-from-equilibrium dynamical evolution, signaled by universal scaling in the gauge-invariant correlation function of the Higgs field. Even when the parameters of the Higgs action do not support condensate formation in the vacuum, during this approach, transient Higgs condensation is observed. We discuss implications of these results for the far-from-equilibrium dynamics of YangMills fields and potential mechanisms of how confinement and condensation in non-Abelian gauge fields can be understood in terms of the dynamics of Higgs models. These suggest that there is an interesting new class of dynamics of strong coherent turbulent gauge fields with condensates.less

  10. Removing Structural Disorder from Oriented TiO2 Nanotube Arrays: Reducing the Dimensionality of Transport and Recombination in Dye-Sensitized Solar Cells

    SciTech Connect (OSTI)

    Zhu, K.; Vinzant, T. B.; Neale, N. R.; Frank, A. J.

    2007-01-01

    We report on the influence of morphological disorder, arising from bundling of nanotubes (NTs) and microcracks in films of oriented TiO{sub 2} NT arrays, on charge transport and recombination in dye-sensitized solar cells (DSSCs). Capillary stress created during evaporation of liquids from the mesopores of dense TiO{sub 2} NT arrays was of sufficient magnitude to induce bundling and microcrack formation. The average lateral deflection of the NTs in the bundles increased with the surface tension of the liquids and with the film thicknesses. The supercritical CO{sub 2} drying technique was used to produce bundle-free and crack-free NT films. Charge transport and recombination properties of sensitized films were studied by frequency-resolved modulated photocurrent/photovoltage spectroscopies. Transport became significantly faster with decreased clustering of the NTs, indicating that bundling creates additional pathways via intertube contacts. Removing such contacts alters the transport mechanism from a combination of one and three dimensions to the expected one dimension and shortens the electron-transport pathway. Reducing intertube contacts also resulted in a lower density of surface recombination centers by minimizing distortion-induced surface defects in bundled NTs. A causal connection between transport and recombination is observed. The dye coverage was greater in the more aligned NT arrays, suggesting that reducing intertube contacts increases the internal surface area of the films accessible to dye molecules. The solar conversion efficiency and photocurrent density were highest for DSSCs incorporating films with more aligned NT arrays owing to an enhanced light-harvesting efficiency. Removing structural disorder from other materials and devices consisting of nominally one-dimensional architectures (e.g., nanowire arrays) should produce similar effects.

  11. Symmetry fractionalization and twist defects

    E-Print Network [OSTI]

    Nicolas Tarantino; Netanel Lindner; Lukasz Fidkowski

    2015-06-22

    Topological order in two dimensions can be described in terms of deconfined quasiparticle excitations - anyons - and their braiding statistics. However, it has recently been realized that this data does not completely describe the situation in the presence of an unbroken global symmetry. In this case, there can be multiple distinct quantum phases with the same anyons and statistics, but with different patterns of symmetry fractionalization - termed symmetry enriched topological (SET) order. When the global symmetry group $G$, which we take to be discrete, does not change topological superselection sectors - i.e. does not change one type of anyon into a different type of anyon - one can imagine a local version of the action of $G$ around each anyon. This leads to projective representations and a group cohomology description of symmetry fractionalization, with $H^2(G,{\\cal A})$ being the relevant group. In this paper, we treat the general case of a symmetry group $G$ possibly permuting anyon types. We show that despite the lack of a local action of $G$, one can still make sense of a so-called twisted group cohomology description of symmetry fractionalization, and show how this data is encoded in the associativity of fusion rules of the extrinsic `twist' defects of the symmetry. Furthermore, building on work of Hermele, we construct a wide class of exactly solved models which exhibit this twisted symmetry fractionalization, and connect them to our formal framework.

  12. Defect Analysis of Vehicle Compressed Natural Gas Composite Cylinder...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Defect Analysis of Vehicle Compressed Natural Gas Composite Cylinder Defect Analysis of Vehicle Compressed Natural Gas Composite Cylinder These slides were presented at the Onboard...

  13. Characterization of structural defects in nuclear graphite IG...

    Office of Scientific and Technical Information (OSTI)

    Characterization of structural defects in nuclear graphite IG-110 and NBG-18 Citation Details In-Document Search Title: Characterization of structural defects in nuclear graphite...

  14. A qualitative study of spin polarization effect in defect tuned Co/graphene/Co nanostructures

    SciTech Connect (OSTI)

    Mandal, Sumit, E-mail: smtdone@gmail.com, E-mail: cnssks@iacs.res.in; Saha, Shyamal K., E-mail: smtdone@gmail.com, E-mail: cnssks@iacs.res.in [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032 (India)

    2014-10-15

    Theoretical reports predict that in contact with a ferromagnetic giant spin, spin polarization evolves in defective graphene since defects in graphene act as local spin moments. We have synthesized different Co/graphene/Co nano spin valve like structures tuning the degree of defect applying ultrasonic vibration and characterized them by Raman spectroscopy. Initially with increasing I{sub D}/I{sub G} ratio in Raman spectra, antiferromagnetic coupling between the Co nanosheets on either sides of graphene enhances leading to betterment in spin transport through graphene. But for highest I{sub D}/I{sub G}, a totally new phenomenon called antiferro quadrupolar ordering (AFQ) takes place which eventually reduces the spin polarization effect.

  15. Self-Assembled ErSb Nanostructures with Optical Applications...

    Office of Scientific and Technical Information (OSTI)

    electrodes - solar, defects, charge transport, materials and chemistry by design, optics, synthesis (novel materials), synthesis (self-assembly), synthesis (scalable...

  16. Controlling n-Type Carrier Density from Er Doping of InGaAs with...

    Office of Scientific and Technical Information (OSTI)

    electrodes - solar, defects, charge transport, materials and chemistry by design, optics, synthesis (novel materials), synthesis (self-assembly), synthesis (scalable...

  17. Key Parameters Governing the Energy Density of Rechargeable Li...

    Office of Scientific and Technical Information (OSTI)

    (heterogeneous), energy storage (including batteries and capacitors), hydrogen and fuel cells, defects, charge transport, membrane, materials and chemistry by design,...

  18. Nanoscale Imaging of Lithium Ion Distribution During In Situ...

    Office of Scientific and Technical Information (OSTI)

    (heterogeneous), energy storage (including batteries and capacitors), hydrogen and fuel cells, defects, charge transport, membrane, materials and chemistry by design,...

  19. In operando X-ray studies of the conversion reaction in Mn3O4...

    Office of Scientific and Technical Information (OSTI)

    (heterogeneous), energy storage (including batteries and capacitors), hydrogen and fuel cells, defects, charge transport, membrane, materials and chemistry by design,...

  20. Electrical charging during the sharkskin instability of a metallocene melt

    E-Print Network [OSTI]

    S. Tonon; A. Lavernhe-Gerbier; F. Flores; A. Allal; C. Guerret-Picourt

    2007-07-18

    Flow instabilities are widely studied because of their economical and theoretical interest, however few results have been published about the polymer electrification during the extrusion. Nevertheless the generation of the electrical charges is characteristic of the interaction between the polymer melt and the die walls. In our study, the capillary extrusion of a metallocene polyethylene (mPE) through a tungsten carbide die is characterized through accurate electrical measurements thanks a Faraday pail. No significant charges are observed since the extrudate surface remains smooth. However, as soon as the sharkskin distortion appears, measurable charges are collected (around 5 10-8 C/m2). Higher level of charges are measured during the spurt or the gross-melt fracture (g.m.f) defects. This work is focused on the electrical charging during the sharkskin instability. The variation of the electrical charges versus the apparent wall shear stress is investigated for different die geometries. This curve exhibits a linear increase, followed by a sudden growth just before the onset of the spurt instability. This abrupt charging corresponds also to the end of the sharkskin instability. It is also well-known that wall slip appears just at the same time, with smaller velocity values than during spurt flow. Our results indicate that electrification could be a signature of the wall slip. We show also that the electrification curves can be shifted according to the time-temperature superposition principle, leading to the conclusion that molecular features of the polymer are also involved in this process.

  1. Di-interstitial defect in silicon revisited

    SciTech Connect (OSTI)

    Londos, C. A.; Antonaras, G.; Chroneos, A.; Department of Materials, Imperial College London, London SW7 2BP

    2013-11-21

    Infrared spectroscopy was used to study the defect spectrum of Cz-Si samples following fast neutron irradiation. We mainly focus on the band at 533 cm{sup ?1}, which disappears from the spectra at ?170 C, exhibiting similar thermal stability with the Si-P6 electron paramagnetic resonance (EPR) spectrum previously correlated with the di-interstitial defect. The suggested structural model of this defect comprises of two self-interstitial atoms located symmetrically around a lattice site Si atom. The band anneals out following a first-order kinetics with an activation energy of 0.88 0.3 eV. This value does not deviate considerably from previously quoted experimental and theoretical values for the di-interstitial defect. The present results indicate that the 533 cm{sup ?1} IR band originates from the same structure as that of the Si-P6 EPR spectrum.

  2. Thermodynamics of Cosmic Defect Network Evolution

    E-Print Network [OSTI]

    Avelino, P P

    2015-01-01

    We show that simple thermodynamic conditions determine, to a great extent, the equation of state and dynamics of cosmic defects of arbitrary dimensionality. We use these conditions to provide a more direct derivation of the Velocity-dependent One-Scale (VOS) model for the macroscopic dynamics of topological defects of arbitrary dimensionality in a $N+1$-dimensional homogeneous and isotropic universe. We parameterize the modifications to the VOS model associated to the interaction of the topological defects with other fields, including, in particular, a new dynamical degree of freedom associated to the variation of the mass per unit $p$-area of the defects, and compute the corresponding scaling solutions. The observational impact of this new dynamical degree of freedom is also briefly discussed.

  3. INNOVATIVE EDDY CURRENT PROBE FOR MICRO DEFECTS

    SciTech Connect (OSTI)

    Santos, Telmo G.; Vilaca, Pedro; Quintino, Luisa [IDMEC, Av. Rovisco Pais, 1049-001 Lisbon (Portugal); Santos, Jorge dos [GKSS, Max-Planck-Street 1, D-21502 Geesthacht (Germany); Rosado, Luis [IST, UTL, Av. Rovisco Pais, 1049-001 Lisbon (Portugal)

    2010-02-22

    This paper reports the development of an innovative eddy current (EC) probe, and its application to micro-defects on the root of the Friction Stir Welding (FSW). The new EC probe presents innovative concept issues, allowing 3D induced current in the material, and a lift-off independence. Validation experiments were performed on aluminium alloys processed by FSW. The results clearly show that the new EC probe is able to detect and sizing surface defects about 60 microns depth.

  4. Reflection and transmission of conformal perturbation defects

    E-Print Network [OSTI]

    Ilka Brunner; Cornelius Schmidt-Colinet

    2015-08-18

    We consider reflection and transmission of interfaces which implement renormalisation group flows between conformal fixed points in two dimensions. Such an RG interface is constructed from the identity defect in the ultraviolet CFT by perturbing the theory on one side of the defect line. We compute reflection and transmission coefficients in perturbation theory to third order in the coupling constant and check our calculations against exact constructions of RG interfaces between coset models.

  5. Reflection and transmission of conformal perturbation defects

    E-Print Network [OSTI]

    Brunner, Ilka

    2015-01-01

    We consider reflection and transmission of interfaces which implement renormalisation group flows between conformal fixed points in two dimensions. Such an RG interface is constructed from the identity defect in the ultraviolet CFT by perturbing the theory on one side of the defect line. We compute reflection and transmission coefficients in perturbation theory to third order in the coupling constant and check our calculations against exact constructions of RG interfaces between coset models.

  6. Short Children with CHARGE Syndrome: Do They Benefit from Growth Hormone Therapy

    E-Print Network [OSTI]

    Drr, H. G.; Boguszewski, M.; Dahlgren, J.; Dunger, D.; Geffner, M. E.; Hokken-Koelega, A. C.; Lindberg, A.; Rooman, R.; KIGS International Board

    2015-05-29

    -test was used for comparisons of outcome measures when applicable otherwise Wilcoxon rang sum test was used, con- sidering difference at less than 5% level as significant (pSAS (SAS Institute, Cary, NC 27513-2414, USA... A: Updated diagnostic criteria for charge syndrome: A proposal. American Journal of Medical genetics Part A 2005;133A:306-308. 5 Jyonouchi S, McDonald-McGinn DM, Bale S, Zackai EH, Sullivan KE: Charge (coloboma, heart defect, atresia choanae...

  7. Electron Scattering in InSb Quantum Wells due to Micro-twin Defects

    SciTech Connect (OSTI)

    Mishima, T. D.; Santos, M. B. [Homer L. Dodge Department of Physics and Astronomy, and Center for Semiconductor Physics in Nanostructure University of Oklahoma, 440 W. Brooks St., Norman, OK 73019 (United States)

    2011-12-26

    The transport electron scattering due to micro-twin (MT) defects in InSb quantum wells (QWs) has been investigated at room temperature (RT). A linear-regression-based scattering analysis showed that Matthiessen's rule is applicable to the RT electron mobility in 20-nm-thick InSb QWs that contain MTs (whose density is 5.6x10{sup 2}-1.2x10{sup 4} /cm) and threading dislocations (8.7x10{sup 8}-3.2x10{sup 9} /cm{sup 2}) as dominant structural defects. For such an InSb QW whose local electron mobility in its non-MT regions is 2.8x10{sup 4}-4.5x10{sup 4} cm{sup 2}/(Vs), the MT-originated energy barrier against the electron transport is deduced to be 0.081-0.093 eV at RT.

  8. Intrinsic structural defects in monolayer molybdenum disulfide

    SciTech Connect (OSTI)

    Zhou, Wu [ORNL; Idrobo Tapia, Juan C [ORNL

    2013-01-01

    Monolayer molybdenum disulfide (MoS2) is a two-dimensional direct band gap semiconductor with distinctive mechanical, electronic, optical and chemical properties that can be utilized for novel nanoelectronics and optoelectronics devices. The performance of these electronic devices strongly depends on the quality and defect morphology of the MoS2 layers. Yet, little is known about the atomic structure of defects present in monolayer MoS2 and their influences on the material properties. Here we provide a systematic study of various intrinsic structural defects, including point defects, grain boundaries, and edges, in chemical vapor phase grown monolayer MoS2 via direct atomic resolution imaging, and explore their energy landscape and electronic properties using first-principles calculations. We discover that one-dimensional metallic wires can be created via two different types of 60 grain boundaries consisting of distinct 4-fold ring chains. A new type of edge reconstruction, representing a transition state during growth, was also identified, providing insights into the material growth mechanism. The atomic scale study of structural defects presented here brings new opportunities to tailor the properties of MoS2 via controlled synthesis and defect engineering.

  9. Sustainable Transportation

    SciTech Connect (OSTI)

    2012-09-01

    This document highlights DOE's Office of Energy Efficiency and Renewable Energy's advancements in transportation technologies, alternative fuels, and fuel cell technologies.

  10. Selective Ionic Transport through Tunable Subnanometer Pores in Single-Layer Graphene Membranes

    E-Print Network [OSTI]

    OHern, Sean C.

    We report selective ionic transport through controlled, high-density, subnanometer diameter pores in macroscopic single-layer graphene membranes. Isolated, reactive defects were first introduced into the graphene lattice ...

  11. taking charge : optimizing urban charging infrastructure for shared electric vehicles

    E-Print Network [OSTI]

    Subramani, Praveen

    2012-01-01

    This thesis analyses the opportunities and constraints of deploying charging infrastructure for shared electric vehicles in urban environments. Existing electric vehicle charging infrastructure for privately owned vehicles ...

  12. Photon: history, mass, charge

    E-Print Network [OSTI]

    L. B. Okun

    2006-02-13

    The talk consists of three parts. ``History'' briefly describes the emergence and evolution of the concept of photon during the first two decades of the 20th century. ``Mass'' gives a short review of the literature on the upper limit of the photon's mass. ``Charge'' is a critical discussion of the existing interpretation of searches for photon charge. Schemes, in which all photons are charged, are grossly inconsistent. A model with three kinds of photons (positive, negative and neutral) seems at first sight to be more consistent, but turns out to have its own serious problems.

  13. Two-dimensional defect modes in optically induced photonic lattices

    SciTech Connect (OSTI)

    Wang Jiandong; Yang Jianke; Chen Zhigang [Department of Mathematics and Statistics, University of Vermont, Burlington, Vermont 05401 (United States); Department of Physics and Astronomy, San Francisco State University, San Francisco, California 94132 (United States)

    2007-07-15

    In this article, localized linear defect modes due to band gap guidance in two-dimensional photonic lattices with localized or nonlocalized defects are investigated theoretically. First, when the defect is localized and weak, eigenvalues of defect modes bifurcated from edges of Bloch bands are derived analytically. It is shown that in an attractive (repulsive) defect, defect modes bifurcate out from Bloch-band edges with normal (anomalous) diffraction coefficients. Furthermore, distances between defect-mode eigenvalues and Bloch-band edges decrease exponentially with the defect strength, which is very different from the one-dimensional case where such distances decrease quadratically with the defect strength. It is also found that some defect-mode branches bifurcate not from Bloch-band edges, but from quasiedge points within Bloch bands, which is very unusual. Second, when the defect is localized but strong, defect modes are determined numerically. It is shown that both the repulsive and attractive defects can support various types of defect modes such as fundamental, dipole, quadrupole, and vortex modes. These modes reside in various band gaps of the photonic lattice. As the defect strength increases, defect modes move from lower band gaps to higher ones when the defect is repulsive, but remain within each band gap when the defect is attractive, similar to the one-dimensional case. The same phenomena are observed when the defect is held fixed while the applied dc field (which controls the lattice potential) increases. Lastly, if the defect is nonlocalized (i.e., it persists at large distances in the lattice), it is shown that defect modes can be embedded inside the continuous spectrum, and they can bifurcate out from edges of the continuous spectrum algebraically rather than exponentially.

  14. Defect equilibria and electrode kinetics in Prx?Ce1?-?x?O2?-?[?d?e?l?t?a?]? mixed conducting thin films : an in-situ optical and electrochemical investigation

    E-Print Network [OSTI]

    Kim Jae Jin, Ph. D

    2015-01-01

    An improved fundamental understanding of oxygen defect equilibria and transport kinetics in oxides is essential for achieving enhanced performance and longevity in many oxide-based practical applications. The ability to ...

  15. Femtosecond-laser Microstructuring of Silicon: Dopants and Defects

    E-Print Network [OSTI]

    Mazur, Eric

    -laser Microstructuring of Silicon: Dopants and Defects Cynthia Friend Michael A. Sheehy Abstract This dissertation deals

  16. Trends in Workplace Charging

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Donofrio Ford Motor Company Trends in Workplace Charging Est EV NA NA approx 21 70-100 Miles: What Types of Chargers are Being Used? Considerations for Campus Installations *...

  17. Vehicle Technologies Office: AVTA - Electric Vehicle Charging...

    Broader source: Energy.gov (indexed) [DOE]

    Fast Charge - November 2012 WirelessInductive Charging Inductive charging, also known as wireless charging, uses an electromagnetic field to transfer electricity to a PEV without...

  18. Electrically charged targets

    DOE Patents [OSTI]

    Goodman, Ronald K. (Livermore, CA); Hunt, Angus L. (Alamo, CA)

    1984-01-01

    Electrically chargeable laser targets and method for forming such charged targets in order to improve their guidance along a predetermined desired trajectory. This is accomplished by the incorporation of a small amount of an additive to the target material which will increase the electrical conductivity thereof, and thereby enhance the charge placed upon the target material for guidance thereof by electrostatic or magnetic steering mechanisms, without adversely affecting the target when illuminated by laser energy.

  19. Strongly coupled plasma with electric and magnetic charges

    E-Print Network [OSTI]

    Jinfeng Liao; Edward Shuryak

    2006-12-12

    A number of theoretical and lattice results lead us to believe that Quark-Gluon Plasma not too far from $T_c$ contains not only electrically charged quasiparticles -- quarks and gluons -- but magnetically charged ones -- monopoles and dyons -- as well. Although binary systems like charge-monopole and charge-dyon were considered in details before in both classical and quantum settings, it is the first study of coexisting electric and magnetic particles in many-body context. We perform Molecular Dynamics study of strongly coupled plasmas with $\\sim 1000$ particles and different fraction of magnetic charges. Correlation functions and Kubo formulae lead to such transport properties as diffusion constant, shear viscosity and electric conductivity: we compare the first two with empirical data from RHIC experiments as well as results from AdS/CFT correspondence. We also study a number of collective excitations in these systems.

  20. Manufacturing Defects Common to Composite Wind Turbine Blades: Effects of Defects

    E-Print Network [OSTI]

    1 Manufacturing Defects Common to Composite Wind Turbine Blades: Effects of Defects Jared W. Nelson The Blade Reliability Collaborative has been formed to perform comprehensive studies to improve wind turbine uni-directional wind turbine fiber-reinforced composite material with an epoxy resin were utilized

  1. A topological point defect regulates the evolution of extended defects in irradiated silicon

    E-Print Network [OSTI]

    Wilkins, John

    functional theory calculations establish formation energies, activation barriers, and electronic structures structure. Compared to the experimental gap of 1.16 eV for bulk Si,16 the calculated HSE gap, 1.15 eV, shows interstitial defects in irradiated silicon. Molecular dynamics simulations reveal the role of the bond defect

  2. Climate change mitigation and co-benefits of feasible transport demand policies in Beijing

    E-Print Network [OSTI]

    Kammen, Daniel M.

    Climate change mitigation and co-benefits of feasible transport demand policies in Beijing Felix i n f o Keywords: Climate change mitigation Transport demand management External costs Urban transportation Road charging a b s t r a c t Urban car transportation is a cause of climate change but is also

  3. Low energy charged particles interacting with amorphous solid water layers

    SciTech Connect (OSTI)

    Horowitz, Yonatan; Asscher, Micha

    2012-04-07

    The interaction of charged particles with condensed water films has been studied extensively in recent years due to its importance in biological systems, ecology as well as interstellar processes. We have studied low energy electrons (3-25 eV) and positive argon ions (55 eV) charging effects on amorphous solid water (ASW) and ice films, 120-1080 ML thick, deposited on ruthenium single crystal under ultrahigh vacuum conditions. Charging the ASW films by both electrons and positive argon ions has been measured using a Kelvin probe for contact potential difference (CPD) detection and found to obey plate capacitor physics. The incoming electrons kinetic energy has defined the maximum measurable CPD values by retarding further impinging electrons. L-defects (shallow traps) are suggested to be populated by the penetrating electrons and stabilize them. Low energy electron transmission measurements (currents of 0.4-1.5 {mu}A) have shown that the maximal and stable CPD values were obtained only after a relatively slow change has been completed within the ASW structure. Once the film has been stabilized, the spontaneous discharge was measured over a period of several hours at 103 {+-} 2 K. Finally, UV laser photo-emission study of the charged films has suggested that the negative charges tend to reside primarily at the ASW-vacuum interface, in good agreement with the known behavior of charged water clusters.

  4. Paradox of Peroxy Defects and Positive Holes in Rocks - Part I: Effect of Temperature

    E-Print Network [OSTI]

    Freund, Friedemann T

    2015-01-01

    Though ubiquitous in minerals of igneous and high-grade metamorphic rocks, peroxy defects have been widely overlooked in the past. The charge carriers of interest are positive holes, chemically equivalent to O$^-$ in a matrix of O$^{2-}$, physically defect electrons in the O$^{2-}$ sublattice, highly mobile, able to propagate fast and far. O$^-$ are oxidized relative to O$^{2-}$. As such O$^-$ are not supposed to exist in minerals and rocks that come from deep within the Earth crust or upper mantle, where the environments are overwhelmingly reduced. In order to understand how peroxy defects are introduced, we look at peroxy defects in a crystallographically and compositionally well characterized model system: single crystals of nominally high-purity MgO, grown from the melt under highly reducing conditions. During crystallization the MgO crystals incorporate OH$^-$ through dissolution of traces of H$_2$O into the MgO matrix, leading to a solid solution (ss) Mg$_{1-\\delta}$(OH)$_{2\\delta}$O$_{1-2\\delta}$, wher...

  5. Displacement fields of point defects in two-dimensional colloidal crystals

    E-Print Network [OSTI]

    Wolfgang Lechner; Elisabeth Schll-Paschinger; Christoph Dellago

    2008-05-20

    Point defects such as interstitials, vacancies, and impurities in otherwise perfect crystals induce complex displacement fields that are of long-range nature. In the present paper we study numerically the response of a two-dimensional colloidal crystal on a triangular lattice to the introduction of an interstitial particle. While far from the defect position the resulting displacement field is accurately described by linear elasticity theory, lattice effects dominate in the vicinity of the defect. In comparing the results of particle based simulations with continuum theory, it is crucial to employ corresponding boundary conditions in both cases. For the periodic boundary condition used here, the equations of elasticity theory can be solved in a consistent way with the technique of Ewald summation familiar from the electrostatics of periodically replicated systems of charges and dipoles. Very good agreement of the displacement fields calculated in this way with those determined in particle simulations is observed for distances of more than about 10 lattice constants. Closer to the interstitial, strongly anisotropic displacement fields with exponential behavior can occur for certain defect configurations. Here we rationalize this behavior with a simple bead-spring that relates the exponential decay constant to the elastic constants of the crystal.

  6. Collision integrals for charged-charged interaction in two-temperature non-equilibrium plasma

    SciTech Connect (OSTI)

    Ghorui, S.; Das, A. K.

    2013-09-15

    Choice of an appropriate form of shielding distance in the estimation of collision integrals under screened coulomb potential for two-temperature non-equilibrium plasma is addressed. Simple expressions for collision integrals for charged-charged interactions are derived. It is shown that while some of the formalisms used earlier completely ignore the presence of ions, the others incorporating it may result in negative collision integrals for the interactions involving particles at higher charged states. The parametric regimes of concern and impact of different formalisms on the computed transport properties are investigated with specific reference to nitrogen plasma. A revised definition of the shielding distance is proposed, which incorporates both electrons and ions, avoids the problem of negative collision integrals in all practical regimes of interest and results in calculated property values in close agreement with experimentally observed results.

  7. Electron transport in pure and substituted iron oxyhydroxides by small-polaron migration

    SciTech Connect (OSTI)

    Alexandrov, Vitali Y.; Rosso, Kevin M.

    2014-08-12

    Iron oxyhydroxides (FeOOH) are common crystalline forms of iron that play a critical role in technology and the natural environment via a variety of important reduction-oxidation reactions, including electrical semiconduction as an aspect. However, a basic understanding of the electron transport properties of these systems is still lacking. We examine the electron mobility in goethite (?-FeOOH), akaganite (?-FeOOH), and lepidocrocite (? -FeOOH) polymorphs by means of density functional theory based (DFT+U) calculations.We show that room temperature charge transport should be dominated by the small-polaron hopping type, and that the attendant mobility should be highest for pure goethite and akaganite. Hopping pathways through the various lattices are discussed in terms of individual electron exchange steps and rates for each. Given the usual occurrence of compositional impurities in natural iron oxyhydroxides, we also investigate the effect of common stoichiometric defects on the electron hopping activation energies such as Al and Cr substitutional cations in goethite, and Cl anions in the channels of akaganite.

  8. Correlation between Charge Inhomogeneities and Structure in Graphene and Other Electronic Crystalline Membranes

    E-Print Network [OSTI]

    Doron Gazit

    2009-10-05

    Only one atom thick and not inclined to lattice defects, graphene represents the ultimate crystalline membrane. However, its structure reveals unique features not found in other crystalline membranes, in particular the existence of ripples with wavelength of 100-300 Angstroms. Here, I trace the origin of this difference to the free electrons in the membrane. The deformation energy of the lattice creates a coupling between charge fluctuations and the structure, resulting in ripples on the membrane, correlated with charge inhomogeneities. In graphene this mechanism reproduces the experimental result for both charge puddles and ripples.

  9. Transportation Plan

    E-Print Network [OSTI]

    Boreo, Andrea; Li, Wei; Wunnenbuger, Douglas; Giusti, Cecilia; Cooper, John T.; Masterson, Jaimie

    2015-01-01

    Mobility throughout a community ensures freedom of movement and enhances quality of life. Traffic congestion, pollution, urban sprawl, social exclusion, safety and health can decrease mobility and should be a part of a sustainable transportation...

  10. electrifyingthefuture transportation

    E-Print Network [OSTI]

    Birmingham, University of

    programme of electrification and the potential introduction of diesel hybrids. The Department for Transport vehicles Wind turbine systems Industrial equipment The lab has full ethernet capability which will enable

  11. Bistable defect structures in blue phase devices

    E-Print Network [OSTI]

    A. Tiribocchi; G. Gonnella; D. Marenduzzo; E. Orlandini; F. Salvadore

    2011-10-28

    Blue phases (BPs) are liquid crystals made up by networks of defects, or disclination lines. While existing phase diagrams show a striking variety of competing metastable topologies for these networks, very little is known as to how to kinetically reach a target structure, or how to switch from one to the other, which is of paramount importance for devices. We theoretically identify two confined blue phase I systems in which by applying an appropriate series of electric field it is possible to select one of two bistable defect patterns. Our results may be used to realise new generation and fast switching energy-saving bistable devices in ultrathin surface treated BPI wafers.

  12. GaN: Defect and Device Issues

    SciTech Connect (OSTI)

    Pearton, S.J.; Ren, F.; Shul, R.J.; Zolper, J.C.

    1998-11-09

    The role of extended and point defects, and key impurities such as C, O and H, on the electrical and optical properties of GaN is reviewed. Recent progress in the development of high reliability contacts, thermal processing, dry and wet etching techniques, implantation doping and isolation and gate insulator technology is detailed. Finally, the performance of GaN-based electronic and photonic devices such as field effect transistors, UV detectors, laser diodes and light-emitting diodes is covered, along with the influence of process-induced or grown-in defects and impurities on the device physics.

  13. The effects of fastener hole defects

    E-Print Network [OSTI]

    Andrews, Scot D.

    1991-01-01

    ) August 1991 ABSTRACT The Effects of Fastener Hole Defects. (August 1991) Scot D. Andrews, B. S. , Texas A8rM University Chair of Advisory Committee: Dr. Orden O. Ochoa The influence of drilling-induced defects, such as delamination, on the fatigue... ambient and elevated temperature wet conditions. Specimens were tested in a bearing tension frame to static failure in order to measure the failure load and to calculate pin bearing stress. From static test results, a fatigue load was selected as 66...

  14. Point Defect Dynamics in Two-Dimensional Colloidal Crystals

    E-Print Network [OSTI]

    A. Libal; C. Reichhardt; C. J. Olson Reichhardt

    2006-12-16

    We study the topological configurations and dynamics of individual point defect vacancies and interstitials in a two-dimensional colloidal crystal. Our Brownian dynamics simulations show that the diffusion mechanism for vacancy defects occurs in two phases. The defect can glide along the crystal lattice directions, and it can rotate during an excited topological transition configuration to assume a different direction for the next period of gliding. The results for the vacancy defects are in good agreement with recent experiments. For the interstitial point defects, which were not studied in the experiments, we find several of the same modes of motion as in the vacancy defect case along with two additional diffusion pathways. The interstitial defects are more mobile than the vacancy defects due to the more two-dimensional nature of the diffusion of the interstitial defects.

  15. Spontaneous symmetry breaking, and strings defects in hypercomplex gauge field theories

    E-Print Network [OSTI]

    Cartas-Fuentevilla, R

    2015-01-01

    Inspired by the appearance of split-complex structures in the dimensional reduction of string theory, and in the theories emerging as byproducts, we study the hyper-complex formulation of Abelian gauge field theories, by incorporating a new complex unit to the usual complex one. The hypercomplex version of the traditional Mexican hat potential associated with the $U(1)$ gauge field theory, corresponds to a {\\it hybrid} potential with two real components, and with $U(1)\\times SO(1,1)$ as symmetry group. Each component corresponds to a deformation of the hat potential, with the appearance of a new degenerate vacuum. Hypercomplex electrodynamics will show novel properties, such as the spontaneous symmetry breaking scenarios with running masses for the vectorial and scalar Higgs fields, and the Aharonov-Bohm type strings defects as exact solutions; these topological defects may be detected only by quantum interference of charged particles through gauge invariant loop integrals. In a particular limit, the {\\it hyp...

  16. Point defects and p-type conductivity in Zn{sub 1x}Mn{sub x}GeAs{sub 2}

    SciTech Connect (OSTI)

    Kilanski, L.; Podgrni, A.; Dynowska, E.; Dobrowolski, W.

    2014-07-14

    Positron annihilation spectroscopy is used to study point defects in Zn{sub 1x}Mn{sub x}GeAs{sub 2} crystals with low Mn content 0?x?0.042 with disordered zincblende and chalcopyrite structure. The role of negatively charged vacancies and non-open-volume defects is discussed with respect to the high p-type conductivity with carrier concentration 10{sup 19}?p?10{sup 21}cm{sup ?3} in our samples. Neutral As vacancies, together with negatively charged Zn vacancies and non-open-volume defects with concentrations around 10{sup 16}?10{sup 18}cm{sup ?3}, are observed to increase with increasing Mn content in the alloy. The observed concentrations of defects are not sufficient to be responsible for the strong p-type conductivity of our crystals. Therefore, we suggest that other types of defects, such as extended defects, have a strong influence on the conductivity of Zn{sub 1x}Mn{sub x}GeAs{sub 2} crystals.

  17. Charged Vacuum Bubble Stability

    E-Print Network [OSTI]

    J. R. Morris

    1998-10-20

    A type of scenario is considered where electrically charged vacuum bubbles, formed from degenerate or nearly degenerate vacuua separated by a thin domain wall, are cosmologically produced due to the breaking of a discrete symmetry, with the bubble charge arising from fermions residing within the domain wall. Stability issues associated with wall tension, fermion gas, and Coulombic effects for such configurations are examined. The stability of a bubble depends upon parameters such as the symmetry breaking scale and the fermion coupling. A dominance of either the Fermi gas or the Coulomb contribution may be realized under certain conditions, depending upon parameter values.

  18. The electrically charged universe

    E-Print Network [OSTI]

    Michael Dren

    2012-01-31

    The paper discusses the possibility of a universe that is not electrically neutral but has a net positive charge. It is claimed that such a universe contains a homogeneous distribution of protons that are not bound to galaxies and fill up the intergalactic space. This proton `gas' charges macroscopic objects like stars and planets, but it does not generate electrostatic or magnetic fields that affect the motion of these bodies significantly. However, the proton gas may contribute significantly to the total dark matter of the universe and its electrostatic potential may contribute to the dark energy and to the expansion of the universe.

  19. Space-charge and emittance blowup in linacs

    SciTech Connect (OSTI)

    Jameson, R.A.

    1982-01-01

    Recent work leading to better understanding of beam emittance under space-charge conditions in linear transport and accelerating channels is reviewed. Some practical considerations are outlined for minimizing emittance growth by properly matching the input beam, including equipartitioning the energy balance, and by avoiding certain areas of tune-shift.

  20. Fermi level control of compensating point defects during metalorganic chemical vapor deposition growth of Si-doped AlGaN

    SciTech Connect (OSTI)

    Bryan, Z; Bryan, I; Gaddy, BE; Reddy, P; Hussey, L; Bobea, M; Guo, W; Hoffmann, M; Kirste, R; Tweedie, J; Gerhold, M; Irving, DL; Sitar, Z; Collazo, R

    2014-12-01

    A Fermi-level control scheme for point defect management using above-bandgap UV illumination during growth is presented. We propose an extension to the analogy between the Fermi level and the electrochemical potential such that the electrochemical potential of a charged defect in a material with steady-state populations of free charge carriers may be expressed in terms of the quasi-Fermi levels. A series of highly Si-doped Al0.65Ga0.35N films grown by metalorganic chemical vapor deposition with and without UV illumination showed that samples grown under UV illumination had increased free carrier concentration, free carrier mobility, and reduced midgap photoluminescence all indicating a reduction in compensating point defects. (c) 2014 AIP Publishing LLC.

  1. NEST Scientific Report 2007-2009 Transport phenomena in self-assembled nanowires

    E-Print Network [OSTI]

    Abbondandolo, Alberto

    and heat transport in nanoscale self-assembled structures is being pursued by the development of hybrid charge and heat transport at the nanoscale. The first aim has started to be pursued in mid 2008 at NEST while an example of SAW-induced charge pumping can be seen in panel (b). In the studied devices both

  2. Defect Analysis of Vehicle Compressed Natural Gas

    E-Print Network [OSTI]

    Cylinder, translated and presented by J. P. Hsu, PhD, Smart Chemistry #12;Reason for Defect Analysis of CNG Composite Cylinder Safety Issue - Four explosion accidents of auto used CNG composite material cylinders resulting huge personnel and vehicles loss. Low Compliance Rate Inspect 12119 Auto used CNG composite

  3. Premelting at Defects Within Bulk Colloidal Crystals

    E-Print Network [OSTI]

    Collings, Peter

    Premelting at Defects Within Bulk Colloidal Crystals A. M. Alsayed,1 M. F. Islam,1 J. Zhang,1 P. J at grain boundaries and dislocations within bulk colloidal crystals using real- time video microscopy. The crystals are equilibrium close-packed, three- dimensional colloidal structures made from thermally

  4. Defect-free ultrahigh flux asymmetric membranes

    DOE Patents [OSTI]

    Pinnau, Ingo (Austin, TX); Koros, William J. (Austin, TX)

    1990-01-01

    Defect-free, ultrahigh flux integrally-skinned asymmetric membranes having extremely thin surface layers (<0.2 .mu.m) comprised of glassy polymers are disclosed. The membranes are formed by casting an appropriate drope followed by forced convective evaporation of solvent to obtain a dry phase separated asymmetrical structure. The structure is then washed in a precipitation liquid and dried.

  5. Charge mobility of discotic mesophases: A multiscale quantum/classical study

    E-Print Network [OSTI]

    J. Kirkpatrick; V. Marcon; J. Nelson; K. Kremer; D. Andrienko

    2007-01-16

    A correlation is established between the molecular structure and charge mobility of discotic mesophases of hexabenzocoronene derivatives by combining electronic structure calculations, Molecular Dynamics, and kinetic Monte Carlo simulations. It is demonstrated that this multiscale approach can provide an accurate ab-initio description of charge transport in organic materials.

  6. Point defect distribution in high-mobility conductive SrTiO{sub 3} crystals

    SciTech Connect (OSTI)

    Gentils, A. [Centre de Spectrometrie Nucleaire et de Spectrometrie de Masse, CNRS-IN2P3-Universite Paris-Sud 11, 91405 Orsay Campus (France); CEMHTI Site Cyclotron, CNRS, 3A rue de la Ferollerie, 45071 Orleans Cedex 2 (France); Copie, O.; Bibes, M.; Bouzehouane, K.; Jacquet, E.; Carretero, C.; Barthelemy, A. [Unite Mixte de Physique CNRS/Thales associee a l'Universite Paris-Sud, Campus de Polytechnique, 1 Avenue A. Fresnel, 91767 Palaiseau (France); Herranz, G. [Unite Mixte de Physique CNRS/Thales associee a l'Universite Paris-Sud, Campus de Polytechnique, 1 Avenue A. Fresnel, 91767 Palaiseau (France); Institut de Ciencia de Materials de Barcelona, ICMAB-CSIC, Campus de la UAB, Bellaterra 08193, Catalonia (Spain); Fortuna, F. [Centre de Spectrometrie Nucleaire et de Spectrometrie de Masse, CNRS-IN2P3-Universite Paris-Sud 11, 91405 Orsay Campus (France); Basletic, M.; Tafra, E.; Hamzic, A. [Department of Physics, Faculty of Science, University of Zagreb, Bijenicka 32, P.O. Box 331, HR-10002 Zagreb (Croatia)

    2010-04-01

    We have carried out positron-annihilation spectroscopy to characterize the spatial distribution and the nature of vacancy defects in insulating as-received as well as in reduced SrTiO{sub 3} substrates exhibiting high-mobility conduction. The substrates were reduced either by ion etching the substrate surfaces or by doping with vacancies during thin-film deposition at low pressure and high temperature. We show that Ti vacancies are native defects homogeneously distributed in as-received substrates. In contrast, the dominant vacancy defects are the same both in ion etched crystals and substrates reduced during the film growth, and they consist of nonhomogeneous distributions of cation-oxygen vacancy complexes. Their spatial extension is tuned from a few microns in ion-etched samples to the whole substrate in specimens reduced during film deposition. Our results shed light on the transport mechanisms of conductive SrTiO{sub 3} crystals and on strategies for defect-engineered oxide quantum wells, wires, and dots.

  7. Image Charge Differential

    E-Print Network [OSTI]

    Weston, Ken

    Image Charge Differential Amplifier FT 0 Crude Oil Time (s) 543210 Frequency (kHz) m/z m q B f organic molecules such as heavy crude oils. Heavy crudes are some of the most complex organic mixtures found in nature. As the crude oil industry grows in size and demand for crude oil increases, techniques

  8. Meningeal Defects alter the tangential migration of cortical interneurons in Foxc1hith/hith mice

    E-Print Network [OSTI]

    Zarbalis, Konstantinos; Choe, Youngshik; Siegenthaler, Julie A; Orosco, Lori A; Pleasure, Samuel J

    2012-01-01

    migration presents the primary mode of migration of corticalbe the primary cause for the observed migration defects.tangen- tial migration defects being a primary defect rather

  9. Strain effects on oxygen transport in tetragonal zirconium dioxide

    SciTech Connect (OSTI)

    Xian-Ming Bai; Yongfeng Zhang; Michael R. Tonks

    2013-11-01

    Temperature accelerated dynamics and molecular dynamics simulations are used to investigate the strain effects on oxygen interstitial and vacancy migration in tetragonal zirconium dioxide. At zero external strain, the anisotropic migration mechanisms of oxygen defects are characterized. At non-zero strains, both the crystal structure and defect migration barriers are modified by strain. Under compressive strains, the defect migration barrier increases with the increasing strain for both interstitials and vacancies. The crystal structure transforms from a tetragonal to a nearly cubic fluorite structure. Accordingly, the defect migration becomes nearly isotropic. Under dilative strains, the migration barrier first decreases then increases with increasing strain for both types of defects. The tetragonal phase transforms to a lower symmetry structure that is close to the orthorhombic phase. In turn, the defect migration becomes highly anisotropic. Under both compressive and dilative strains, interstitials respond to strain more strongly than vacancies. At small dilative strains, an oxygen interstitial has comparable diffusivity to a vacancy, suggesting that both types of defects can contribute to oxygen transport, if they are present. Although currently no previous result is available to validate oxygen interstitial diffusion behavior, the trend of strain effects on oxygen vacancy diffusion is in good agreement with available experimental and theoretical studies in the literature.

  10. Healing of defects in a two-dimensional granular crystal

    E-Print Network [OSTI]

    Rice, Marie C

    2014-01-01

    Using a macroscopic analog for a two dimensional hexagonal crystal, we perform an experimental investigation of the self-healing properties of circular grain defects with an emphasis on defect orientation. A circular grain ...

  11. Estimating the expected latency to failure due to manufacturing defects

    E-Print Network [OSTI]

    Dorsey, David Michael

    2004-09-30

    Manufacturers of digital circuits test their products to find defective parts so they are not sold to customers. Despite extensive testing, some of their products that are defective pass the testing process. To combat ...

  12. Defect site prediction based upon statistical analysis of fault signatures

    E-Print Network [OSTI]

    Trinka, Michael Robert

    2004-09-30

    Good failure analysis is the ability to determine the site of a circuit defect quickly and accurately. We propose a method for defect site prediction that is based on a site's probability of excitation, making no assumptions about the type...

  13. Sandia Energy - Research Challenge 4: Defect-Carrier Interactions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    technology challenges. research-challenge-4-defect-carrier-interactions-5001 Measured density of an InGaN quantum well (QW) deep-level defect located 0.15 eV above the valence...

  14. Gated charged-particle trap

    DOE Patents [OSTI]

    Benner, W. Henry (Danville, CA)

    1999-01-01

    The design and operation of a new type of charged-particle trap provides simultaneous measurements of mass, charge, and velocity of large electrospray ions. The trap consists of a detector tube mounted between two sets of center-bored trapping plates. Voltages applied to the trapping plates define symmetrically-opposing potential valleys which guide axially-injected ions to cycle back and forth through the charge-detection tube. A low noise charge-sensitive amplifier, connected to the tube, reproduces the image charge of individual ions as they pass through the detector tube. Ion mass is calculated from measurement of ion charge and velocity following each passage through the detector.

  15. Transport in holographic superfluids

    E-Print Network [OSTI]

    Christopher P. Herzog; Nir Lisker; Piotr Surowka; Amos Yarom

    2011-01-17

    We construct a slowly varying space-time dependent holographic superfluid and compute its transport coefficients. Our solution is presented as a series expansion in inverse powers of the charge of the order parameter. We find that the shear viscosity associated with the motion of the condensate vanishes. The diffusion coefficient of the superfluid is continuous across the phase transition while its third bulk viscosity is found to diverge at the critical temperature. As was previously shown, the ratio of the shear viscosity of the normal component to the entropy density is 1/(4 pi). As a consequence of our analysis we obtain an analytic expression for the backreacted metric near the phase transition for a particular type of holographic superfluid.

  16. Excited states and optical absorption of small semiconducting clusters: Dopants, defects and charging

    E-Print Network [OSTI]

    lasers,14 and photovoltaic cells.15,16 Understanding of the nature of electronic excitations in NCs, then a phenomenon known as multiple exciton generation (MEG) can occur, in which more than one exciton is created current in a material and thus increase the maximum efficiency of solar cells by about a third,17

  17. AVTA: ChargePoint AC Level 2 Charging System Testing Results...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ChargePoint AC Level 2 Charging System Testing Results AVTA: ChargePoint AC Level 2 Charging System Testing Results The Vehicle Technologies Office's Advanced Vehicle Testing...

  18. Workplace Charging Challenge: Sample Municipal Workplace Charging Agreement

    Broader source: Energy.gov [DOE]

    Review the agreement proposed by one municipality to register PEV drivers and inform staff of charging policy.

  19. Charging effects and quantum crossover in granular superconductors

    SciTech Connect (OSTI)

    Granato, E. (LAS, Instituto Nacional de Pesquisas Espaciais, 12.225 Sao Jose dos Campos, Sao Paulo (Brazil)); Continentino, M.A. (Instituto de Fisica, Universidade Federal Fluminense, Outeiro de S.J. Batista s/n, Niteroi, 24.020, Rio de Janeiro (Brazil))

    1993-12-01

    The effects of the charging energy in the superconducting transition of granular materials or Josephson-junction arrays are investigated using a pseudo-spin-one model. Within a mean-field renormalization-group approach, we obtain the phase diagram as a function of temperature and charging energy. In contrast to earlier treatments, we find no sign of a reentrant transition in agreement with more recent studies. A crossover line is identified in the nonsuperconducting side of the phase diagram and along which we expect to observe anomalies in the transport and thermodynamic properties. We also study a charge ordering phase, which can appear for large nearest-neighbor Coulomb interaction, and show that it leads to first-order transitions at low temperatures. We argue that, in the presence of charge ordering, a nonmonotonic behavior with decreasing temperature is possible with a maximum in the resistance just before entering the superconducting phase.

  20. Evaluating Static Analysis Defect Warnings On Production Software

    E-Print Network [OSTI]

    Cortes, Corinna

    , software quality 1. Introduction Static analysis for software defect detection has become a popular topicEvaluating Static Analysis Defect Warnings On Production Software Nathaniel Ayewah, William Pugh,jpenix,zhou@google.com Abstract Static analysis tools for software defect detection are becoming widely used in practice. However

  1. Clustering Static Analysis Defect Reports to Reduce Maintenance Costs

    E-Print Network [OSTI]

    Weimer, Westley

    Clustering Static Analysis Defect Reports to Reduce Maintenance Costs Zachary P. Fry and Westley, for large systems, these tools often produce an overwhelming number of defect reports. Many of these defect reports are conceptually similar, but addressing each report separately costs developer effort

  2. Research in transportation: the shape of the future

    SciTech Connect (OSTI)

    Chenea, P.F.

    1981-01-01

    The individual mobility now enjoyed due to advancements in the transportation sector is being threatened by higher fuel costs and declining petroleum resources. Transportation research approaches must address these problems. Automotive engineers must redesign existing vehicles to make them smaller, lighter, and so more fuel efficient. Alternatives to the gasoline engine, such as gas turbine and stratified charge engines, must be commercialized.

  3. Turbulence and Transport The Secrets of Magnetic Confinement

    E-Print Network [OSTI]

    Greenwald, Martin

    Magnetic Confinement Takes advantage of the motion of charged particles in a magnetic field. HOW DO WE DO. In Toroidal devices, plasma is confined by Poloidal magnetic fields #12;\\COLLISIONAL TRANSPORT ITurbulence and Transport The Secrets of Magnetic Confinement Presented by Martin Greenwald MIT

  4. "Light-Induced Charge Transport within a Single Asymmetric Nanowire"

    E-Print Network [OSTI]

    LIU, CHONG

    2013-01-01

    and the overall solar energy conversion efficiency cansolar spectrum, 7 and it was predicted that such a scheme could lead to a PEC system with energy conversion

  5. Quasipercolation: Charge transport in fluctuating systems Robert Schiller

    E-Print Network [OSTI]

    Vertes, Akos

    distribution of continuous time random walk, formulas for relative mobility as a function of the expectation value of proportion of high mobility regions are suggested. The results compare reasonably well such a system only if the proportion of conduct- ing elements is high enough to form at least one con- tiguous

  6. Charge Transport through Organized Organic Assemblies in Confined Geometries

    E-Print Network [OSTI]

    Schuckman, Amanda Eileen

    2012-07-16

    . ........................................................................................................ 122 4.10 Bias-induced switching of 5 day soaked zinc porphyrin thiol in dodecanethiol matrix. UHV-STM images of the (a) OFF state at 1.4 V and 20 pA and (c) the corresponding 3-D version. (b) The ON state of zinc porphyrin thiol molecules...,B) Representative UHV-STM images of 1 day pure free-base cis- bipodal porphyrin thiol SAM; imaging conditions: 1.4 V and 20 pA. ....... 149 5.9 (A ? D) AFM topography images of 3 day free-base cis-bipodal porphyrin thiol/C12 mixed SAM...

  7. Charge transport in hybrid nanorod-polymer composite photovoltaic cells

    E-Print Network [OSTI]

    Huynh, Wendy U.; Dittmer, Janke J.; Teclemariam, Nerayo; Milliron, Delia; Alivisatos, A. Paul; Barnham, Keith W.J.

    2002-01-01

    circuit diagram for a photovoltaic cell under illumination.devices such as photovoltaic cells and light-emitting-Polymer Composite Photovoltaic Cells Wendy U. Huynh ,

  8. Graphene Produces More Efficient Charge Transport Inside an Organic...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    integrated into opto-electronic devices, enabling the formation of efficient thin film and flexible devices. There is a growing interest in "blending" graphene with...

  9. A Simple Index for Characterizing Charge Transport in Molecular...

    Office of Scientific and Technical Information (OSTI)

    University Research Org: Energy Frontier Research Centers (EFRC); Argonne-Northwestern Solar Energy Research Center (ANSER) Sponsoring Org: USDOE SC Office of Basic Energy...

  10. Comprehensive computer model for magnetron sputtering. II. Charged particle transport

    SciTech Connect (OSTI)

    Jimenez, Francisco J., E-mail: fjimenez@ualberta.ca; Dew, Steven K. [Department of Electrical and Computer Engineering, University of Alberta, Edmonton T6G 2V4 (Canada); Field, David J. [Smith and Nephew (Alberta) Inc., Fort Saskatchewan T8L 4K4 (Canada)

    2014-11-01

    Discharges for magnetron sputter thin film deposition systems involve complex plasmas that are sensitively dependent on magnetic field configuration and strength, working gas species and pressure, chamber geometry, and discharge power. The authors present a numerical formulation for the general solution of these plasmas as a component of a comprehensive simulation capability for planar magnetron sputtering. This is an extensible, fully three-dimensional model supporting realistic magnetic fields and is self-consistently solvable on a desktop computer. The plasma model features a hybrid approach involving a Monte Carlo treatment of energetic electrons and ions, along with a coupled fluid model for thermalized particles. Validation against a well-known one-dimensional system is presented. Various strategies for improving numerical stability are investigated as is the sensitivity of the solution to various model and process parameters. In particular, the effect of magnetic field, argon gas pressure, and discharge power are studied.

  11. The impact of disorder on charge transport in three dimensional...

    Office of Scientific and Technical Information (OSTI)

    B., E-mail: b.puthen-veettil@unsw.edu.au ; Patterson, R. ; Knig, D. ; Conibeer, G. ; Green, M. A. 1 + Show Author Affiliations Australian Centre for Advanced Photovoltaics,...

  12. Microstructure and charge carrier transport in phthalocyanine based semiconductor blends

    E-Print Network [OSTI]

    Schreiber, Frank

    the field of organic photovoltaics: Yu et al. reported a polymeric solar cell with an interpenetrating donor. The application of distributed interfaces in organic solar cells has the advantage that excitons can efficiently comprises ambipolar field-effect transistors as well as organic photovoltaic cells. Structural, optical

  13. Influence of Topological Spin Fluctuations on Charge Transport

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    hexagonal Brillouin zone. Solid curves are from mean-field calculations D. J. Singh, Phys. Rev. B 61, 13397 (2000). Co t2g and O 2p indicate the origin of the bands is...

  14. Charged Particle Energization and Transport in the Magnetotail during Substorms

    E-Print Network [OSTI]

    Pan, Qingjiang

    2015-01-01

    Owen (2011), Plasma jet braking: energy dissipation and non-Hones Jr. (1979), High-energy magnetospheric protons andof energetic electrons energy ( E ? 200 keV ) in the earths

  15. Charged Particle Energization and Transport in the Magnetotail during Substorms

    E-Print Network [OSTI]

    Pan, Qingjiang

    2015-01-01

    Maxwellian and high-energy power law electrons is consistentdistribution with a high-energy power law tail [Pan et al. ,that adding a high- energy power law tail with E ? ~ 10 keV

  16. Charge Transport Anisotropy Due to Grain Boundaries in Directionally

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D BGene Network ShapingDate:CharacterizationCrystallized Thin Films

  17. A General Relationship between Disorder, Aggregation, and Charge Transport

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach HomeA Better Anode Design to Improve Lithium-Ion Batteries Print Lithium-ionA First Look atin BiNiO3GCMin

  18. Charge Transport in Thin Film Ionomers | Argonne Leadership Computing

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room News PublicationsAudits &BradburyMayARM-0501 Marine Stratus Radiation, Aerosol, and001

  19. Charge Transport within a Three-Dimensional DNA Nanostructure Framework

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room News PublicationsAudits &BradburyMayARM-0501 Marine Stratus Radiation, Aerosol,

  20. Charge Transport Across Insulating Self-Assembled Mono layers:

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing Bacteria (TechnicalTransmission,TextitSciTech Connect TechnicalChanges

  1. A Simple Index for Characterizing Charge Transport in Molecular Materials

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield MunicipalTechnicalInformation4563 LLNL(Technical Report) |(Conference) | SciTechofTechnical

  2. Workplace Charging Challenge Partner: U.S. Department of Transportation |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematics And Statistics » USAJobs SearchAMERICA'SEnergyofThe Hartford Workplace

  3. Influence of Topological Spin Fluctuations on Charge Transport

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACT EVALUATION PLAN FOR THEVortices Influence of DomainChange

  4. Influence of Topological Spin Fluctuations on Charge Transport

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACT EVALUATION PLAN FOR THEVortices Influence of DomainChangeInfluence

  5. Influence of Topological Spin Fluctuations on Charge Transport

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACT EVALUATION PLAN FOR THEVortices Influence of

  6. Influence of Topological Spin Fluctuations on Charge Transport

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACT EVALUATION PLAN FOR THEVortices Influence ofInfluence of

  7. Influence of Topological Spin Fluctuations on Charge Transport

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACT EVALUATION PLAN FOR THEVortices Influence ofInfluence ofInfluence

  8. Influence of Topological Spin Fluctuations on Charge Transport

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation CurrentHenry Bellamy,ImpactScientificInfluence of Topological Spin Fluctuations

  9. Graphene Produces More Efficient Charge Transport Inside an Organic

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverse (Journalvivo Low-Dose Low LETUsefulJorgeAtlDay DraftReport,Mansfield

  10. Modeling defective part level due to static and dynamic defects based upon site observation and excitation balance

    E-Print Network [OSTI]

    Dworak, Jennifer Lynn

    2004-09-30

    a subset that detects a high percentage of the defective parts and produces a low defective part level. Historically, test pattern generation has often been seen as a deterministic endeavor. Test sets are generated to deterministically ensure that a...

  11. Enhancing metal-insulator-insulator-metal tunnel diodes via defect enhanced direct tunneling

    SciTech Connect (OSTI)

    Alimardani, Nasir; Conley, John F.

    2014-08-25

    Metal-insulator-insulator-metal tunnel diodes with dissimilar work function electrodes and nanolaminate Al{sub 2}O{sub 3}-Ta{sub 2}O{sub 5} bilayer tunnel barriers deposited by atomic layer deposition are investigated. This combination of high and low electron affinity insulators, each with different dominant conduction mechanisms (tunneling and Frenkel-Poole emission), results in improved low voltage asymmetry and non-linearity of current versus voltage behavior. These improvements are due to defect enhanced direct tunneling in which electrons transport across the Ta{sub 2}O{sub 5} via defect based conduction before tunneling directly through the Al{sub 2}O{sub 3}, effectively narrowing the tunnel barrier. Conduction through the device is dominated by tunneling, and operation is relatively insensitive to temperature.

  12. Means and method for the focusing and acceleration of parallel beams of charged particles

    DOE Patents [OSTI]

    Maschke, Alfred W. (East Moriches, NY)

    1983-07-05

    A novel apparatus and method for focussing beams of charged particles comprising planar arrays of electrostatic quadrupoles. The quadrupole arrays may comprise electrodes which are shared by two or more quadrupoles. Such quadrupole arrays are particularly adapted to providing strong focussing forces for high current, high brightness, beams of charged particles, said beams further comprising a plurality of parallel beams, or beamlets, each such beamlet being focussed by one quadrupole of the array. Such arrays may be incorporated in various devices wherein beams of charged particles are accelerated or transported, such as linear accelerators, klystron tubes, beam transport lines, etc.

  13. Automakers and Workplace Charging

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum Based Fuels Research atDepartmentAudits and6AuidtWorkplace Charging Summit

  14. On the Proton charge extensions

    E-Print Network [OSTI]

    M. Gluck

    2015-02-03

    It is shown that the recent determination of the various proton charge extensions is compatible with Standard Model expectations.

  15. The ATLAS Data Quality Defect Database System

    E-Print Network [OSTI]

    T. Golling; H. S. Hayward; P. U. E. Onyisi; H. J. Stelzer; P. Waller

    2012-05-14

    The ATLAS experiment at the Large Hadron Collider has implemented a new system for recording information on detector status and data quality, and for transmitting this information to users performing physics analysis. This system revolves around the concept of "defects," which are well-defined, fine-grained, unambiguous occurrences affecting the quality of recorded data. The motivation, implementation, and operation of this system is described.

  16. Tools for charged Higgs bosons

    E-Print Network [OSTI]

    Oscar Stl

    2010-12-13

    We review the status of publicly available software tools applicable to charged Higgs physics. A selection of codes are highlighted in more detail, focusing on new developments that have taken place since the previous charged Higgs workshop in 2008. We conclude that phenomenologists now have the tools ready to face the LHC data. A new webpage collecting charged Higgs resources is presented.

  17. Dark matter from decaying topological defects

    SciTech Connect (OSTI)

    Hindmarsh, Mark [Helsinki Institute of Physics, Gustaf Hllstrmin katu, P.O. Box 64, 00014 Helsinki University (Finland); Kirk, Russell; West, Stephen M., E-mail: m.b.hindmarsh@sussex.ac.uk, E-mail: russell.kirk.2008@live.rhul.ac.uk, E-mail: stephen.west@rhul.ac.uk [Dept. of Physics, Royal Holloway University of London, Egham Hill, Egham, Surrey, TW20 0EX (United Kingdom)

    2014-03-01

    We study dark matter production by decaying topological defects, in particular cosmic strings. In topological defect or ''top-down'' (TD) scenarios, the dark matter injection rate varies as a power law with time with exponent p?4. We find a formula in closed form for the yield for all p < 3/2, which accurately reproduces the solution of the Boltzmann equation. We investigate two scenarios (p = 1, p = 7/6) motivated by cosmic strings which decay into TeV-scale states with a high branching fraction into dark matter particles. For dark matter models annihilating either by s-wave or p-wave, we find the regions of parameter space where the TD model can account for the dark matter relic density as measured by Planck. We find that topological defects can be the principal source of dark matter, even when the standard freeze-out calculation under-predicts the relic density and hence can lead to potentially large ''boost factor'' enhancements in the dark matter annihilation rate. We examine dark matter model-independent limits on this scenario arising from unitarity and discuss example model-dependent limits coming from indirect dark matter search experiments. In the four cases studied, the upper bound on G? for strings with an appreciable channel into TeV-scale states is significantly more stringent than the current Cosmic Microwave Background limits.

  18. Workplace Charging Challenge Progress Update 2014

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    4 Progress Update 2014: Employers Take Charge Available at energy.goveerevehiclesev-everywhere-workplace-charging-challenge Workplace Charging Challenge 5 Cumulative...

  19. Preface: Nonclassical Transport

    E-Print Network [OSTI]

    Bolshov, L.

    2010-01-01

    models of solute transport in highly heterogeneous geologicSemenov. 2008b. Nonclassical transport processes in geologicand L. Matveev. 2008. Transport regimes and concentration

  20. Intelligent Transport Systems

    E-Print Network [OSTI]

    Deakin, Elizabeth; Frick, Karen Trapenberg; Skabardonis, Alexander

    2009-01-01

    in Sustainable Urban Transport: City Interview Synthesis (of Leeds, Institute for Transport Studies, forthcoming.I NTELLIGENT TRANSPORT SYSTEMS LINKING TECHNOLOGY AND

  1. Sustainability and Transport

    E-Print Network [OSTI]

    Gilbert, Richard

    2006-01-01

    Gilbert is a Toronto-based transport and energy consultantof the forthcoming book Transport Revolutions: Making theand substantial transition to transport systems based on

  2. Sandia Energy - Transportation Safety

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Transportation Safety Home Stationary Power Nuclear Fuel Cycle Nuclear Energy Safety Technologies Risk and Safety Assessment Transportation Safety Transportation SafetyTara...

  3. Determination of Grain Boundary Charging in Cu(In,Ga)Se2 Thin Films: Preprint

    SciTech Connect (OSTI)

    Jiang, C. S.; Contreras, M. A.; Repins, I.; Moutinho, H. R.; Noufi, R.; Al-Jassim, M. M.

    2012-06-01

    Surface potential mapping of Cu(In,Ga)Se2 (CIGS) thin films using scanning Kelvin probe force microscopy (SKPFM) aims to understand the minority-carrier recombination at the grain boundaries (GBs) of this polycrystalline material by examining GB charging, which has resulted in a number of publications. However, the reported results are highly inconsistent. In this paper, we report on the potential mapping by measuring wide-bandgap or high-Ga-content films and by using a complementary atomic force microscopy-based electrical technique of scanning capacitance microscopy (SCM). The results demonstrate consistent, positively charged GBs on our high-quality films with minimal surface defects/charges. The potential image taken on a low-quality film with a 1.2-eV bandgap shows significantly degraded potential contrast on the GBs and degraded potential uniformity on grain surfaces, resulting from the surface defects/charges of the low-quality film. In contrast, the potential image on an improved high-quality film with the same wide bandgap shows significantly improved GB potential contrast and surface potential uniformity, indicating that the effect of surface defects is critical when examining GB charging using surface potential data. In addition, we discuss the effect of the SKPFM setup on the validity of potential measurement, to exclude possible artifacts due to improper SKPFM setups. The SKPFM results were corroborated by using SCM measurements on the films with a CdS buffer layer. The SCM image shows clear GB contrast, indicating different electrical impedance on the GB from the grain surface. Further, we found that the GB contrast disappeared when the CdS window layer was deposited after the CIGS film was exposed extensively to ambient, which was caused by the creation of CIGS surface defects by the ambient exposure.

  4. Fractional charges and Misner-Wheeler charge without charge effect in metamaterials

    E-Print Network [OSTI]

    Igor I. Smolyaninov

    2014-12-08

    Optical space in metamaterials may be engineered to emulate four dimensional Kaluza-Klein theory. Nonlinear optics of such metamaterials mimics interaction of quantized electric charges. An electromagnetic wormhole is designed, which connects two points of such an optical space and changes its effective topology. Electromagnetic field configurations which exhibit fractional charges appear as a result of such topology change. Moreover, such effects as Misner-Wheeler charge without charge may be replicated.

  5. A single-molecule approach to ZnO defect studies: Single photons and single defects

    SciTech Connect (OSTI)

    Jungwirth, N. R.; Pai, Y. Y.; Chang, H. S.; MacQuarrie, E. R.; Nguyen, K. X.; Fuchs, G. D.

    2014-07-28

    Investigations that probe defects one at a time offer a unique opportunity to observe properties and dynamics that are washed out of ensemble measurements. Here, we present confocal fluorescence measurements of individual defects in ZnO nanoparticles and sputtered films that are excited with sub-bandgap energy light. Photon correlation measurements yield both antibunching and bunching, indicative of single-photon emission from isolated defects that possess a metastable shelving state. The single-photon emission is in the range of ?560720?nm and typically exhibits two broad spectral peaks separated by ?150?meV. The excited state lifetimes range from 1 to 13?ns, consistent with the finite-size and surface effects of nanoparticles and small grains. We also observe discrete jumps in the fluorescence intensity between a bright state and a dark state. The dwell times in each state are exponentially distributed and the average dwell time in the bright (dark) state does (may) depend on the power of the exciting laser. Taken together, our measurements demonstrate the utility of a single-molecule approach to semiconductor defect studies and highlight ZnO as a potential host material for single-defect based applications.

  6. Spontaneous symmetry breaking, and strings defects in hypercomplex gauge field theories

    E-Print Network [OSTI]

    R. Cartas-Fuentevilla; O. Meza-Aldama

    2015-06-14

    Inspired by the appearance of split-complex structures in the dimensional reduction of string theory, and in the theories emerging as byproducts, we study the hyper-complex formulation of Abelian gauge field theories, by incorporating a new complex unit to the usual complex one. The hypercomplex version of the traditional Mexican hat potential associated with the $U(1)$ gauge field theory, corresponds to a {\\it hybrid} potential with two real components, and with $U(1)\\times SO(1,1)$ as symmetry group. Each component corresponds to a deformation of the hat potential, with the appearance of a new degenerate vacuum. Hypercomplex electrodynamics will show novel properties, such as the spontaneous symmetry breaking scenarios with running masses for the vectorial and scalar Higgs fields, and the Aharonov-Bohm type strings defects as exact solutions; these topological defects may be detected only by quantum interference of charged particles through gauge invariant loop integrals. In a particular limit, the {\\it hyperbolic} electrodynamics does not admit topological defects associated with continuous symmetries

  7. The role of point defects and defect complexes in silicon device processing. Summary report and papers

    SciTech Connect (OSTI)

    Sopori, B.; Tan, T.Y.

    1994-08-01

    This report is a summary of a workshop hold on August 24--26, 1992. Session 1 of the conference discussed characteristics of various commercial photovoltaic silicon substrates, the nature of impurities and defects in them, and how they are related to the material growth. Session 2 on point defects reviewed the capabilities of theoretical approaches to determine equilibrium structure of defects in the silicon lattice arising from transitional metal impurities and hydrogen. Session 3 was devoted to a discussion of the surface photovoltaic method for characterizing bulk wafer lifetimes, and to detailed studies on the effectiveness of various gettering operations on reducing the deleterious effects of transition metals. Papers presented at the conference are also included in this summary report.

  8. Statistics of non-affine defect precursors: tailoring defect densities in colloidal crystals using external fields

    E-Print Network [OSTI]

    Saswati Ganguly; Surajit Sengupta; Peter Sollich

    2015-01-30

    Coarse-graining atomic displacements in a solid produces both local affine strains and "non-affine" fluctuations. Here we study the equilibrium dynamics of these coarse grained quantities to obtain space-time dependent correlation functions. We show how a subset of these thermally excited, non-affine fluctuations act as precursors for the nucleation of lattice defects and suggest how defect probabilities may be altered by an {\\it experimentally realisable} "external" field conjugate to the global non-affinity parameter. Our results are amenable to verification in experiments on colloidal crystals using commonly available holographic laser tweezer and video microscopy techniques, and may lead to simple ways of controlling the defect density of a colloidal solid.

  9. SUSTAINABLE TRANSPORTATION ENERGY PATHWAYS

    E-Print Network [OSTI]

    California at Davis, University of

    SUSTAINABLE TRANSPORTATION ENERGY PATHWAYS A Research Summary for Decision Makers Edited by Joan Ogden and Lorraine Anderson #12;SUSTAINABLE TRANSPORTATION ENERGY PATHWAYS #12;SUSTAINABLE;6 SUSTAINABLE TRANSPORTATION ENERGY PATHWAYS ACKNOWLEDGEMENTS #12;1 SUSTAINABLE TRANSPORTATION ENERGY PATHWAYS

  10. Too expensive to meter: The influence of transaction costs in transportation and

    E-Print Network [OSTI]

    Odlyzko, Andrew M.

    , London Underground, London railways, collection costs, transaction costs, public transport 1 IntroductionToo expensive to meter: The influence of transaction costs in transportation and communication, and that in many cases such charging may lead to undesirable outcomes. Keywords: Transport, Telecommunications

  11. Battery charging control methods, electric vehicle charging methods, battery charging apparatuses and rechargeable battery systems

    DOE Patents [OSTI]

    Tuffner, Francis K. (Richland, WA); Kintner-Meyer, Michael C. W. (Richland, WA); Hammerstrom, Donald J. (West Richland, WA); Pratt, Richard M. (Richland, WA)

    2012-05-22

    Battery charging control methods, electric vehicle charging methods, battery charging apparatuses and rechargeable battery systems. According to one aspect, a battery charging control method includes accessing information regarding a presence of at least one of a surplus and a deficiency of electrical energy upon an electrical power distribution system at a plurality of different moments in time, and using the information, controlling an adjustment of an amount of the electrical energy provided from the electrical power distribution system to a rechargeable battery to charge the rechargeable battery.

  12. Sewerage service charges

    E-Print Network [OSTI]

    Wright, Samuel Robert

    1946-01-01

    of Sewerage Revenues to Water Revenues in 192 Texas Cities. ? ? ? ? ? ? ? ? ? ? ? ? ? 56 X. Population Equivalents of Some Industrial Wastes. . . . 71 XI. Population Equivalents of Some Industrial Wastes. . . . 72 XII. Population Equivalents of Some... be severely criticized, yet they often think it quite proper to take the waste products from the industry, transport them away, purify them, and dispose of them at the taxpayers' expense* Many cities have fixed their tax rates at the maximum permitted...

  13. Efficiency Considerations of Diesel Premixed Charge Compression...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Efficiency Considerations of Diesel Premixed Charge Compression Ignition Combustion Efficiency Considerations of Diesel Premixed Charge Compression Ignition Combustion Poster...

  14. Workplace Charging Challenge Partner: University of Maryland...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Maryland Baltimore Washington Medical Center Workplace Charging Challenge Partner: University of Maryland Baltimore Washington Medical Center Workplace Charging Challenge Partner:...

  15. EV Everywhere Consumer Acceptance and Charging Infrastructure...

    Broader source: Energy.gov (indexed) [DOE]

    dreportoutcaci.pdf More Documents & Publications EV Everywhere Consumer Acceptance and Charging Infrastructure Workshop: Charging Infrastructure Group E...

  16. Workplace Charging Challenge Partner: Bosch Automotive Service...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Bosch Automotive Service Solutions, Inc. Workplace Charging Challenge Partner: Bosch Automotive Service Solutions, Inc. Workplace Charging Challenge Partner: Bosch Automotive...

  17. Workplace Charging Challenge Partner: University of California...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    California, Santa Barbara Workplace Charging Challenge Partner: University of California, Santa Barbara Workplace Charging Challenge Partner: University of California, Santa...

  18. Charge Collection Efficiency Simulations of Irradiated Silicon Strip Detectors

    E-Print Network [OSTI]

    T. Peltola

    2014-11-25

    During the scheduled high luminosity upgrade of LHC, the world's largest particle physics accelerator at CERN, the position sensitive silicon detectors installed in the vertex and tracking part of the CMS experiment will face more intense radiation environment than the present system was designed for. Thus, to upgrade the tracker to required performance level, comprehensive measurements and simulations studies have already been carried out. Essential information of the performance of an irradiated silicon detector is obtained by monitoring its charge collection efficiency (CCE). From the evolution of CCE with fluence, it is possible to directly observe the effect of the radiation induced defects to the ability of the detector to collect charge carriers generated by traversing minimum ionizing particles (mip). In this paper the numerically simulated CCE and CCE loss between the strips of irradiated silicon strip detectors are presented. The simulations based on Synopsys Sentaurus TCAD framework were performed before and after irradiation for fluences up to $1.5\\times10^{15}$ $\\textrm{n}_{\\textrm{eq}}$cm$^{-2}$ for the n-on-p sensors. A two level and non-uniform three level defect models were applied for the proton irradiation simulations and two level model for neutrons. The results are presented together with the measurements of strip detectors irradiated by different particles and fluences and show considerable agreement for both CCE and its position dependency.

  19. Beam Transport

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room News PublicationsAudits & Inspections AuditsBarbara McClintockSecurityBeam Transport Beam

  20. Stochastic Transport

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effect Photovoltaics -7541C.3X-rays3 Prepared by:'!Transport in PPCD Discharges by

  1. Greening Transportation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HABFESOpportunitiesNERSC GettingGraphene's 3DGreenGreenTransportation

  2. Method of identifying defective particle coatings

    DOE Patents [OSTI]

    Cohen, Mark E. (San Diego, CA); Whiting, Carlton D. (San Diego, CA)

    1986-01-01

    A method for identifying coated particles having defective coatings desig to retain therewithin a build-up of gaseous materials including: (a) Pulling a vacuum on the particles; (b) Backfilling the particles at atmospheric pressure with a liquid capable of wetting the exterior surface of the coated particles, said liquid being a compound which includes an element having an atomic number higher than the highest atomic number of any element in the composition which forms the exterior surface of the particle coating; (c) Drying the particles; and (d) Radiographing the particles. By television monitoring, examination of the radiographs is substantially enhanced.

  3. Integrated circuit failure analysis by low-energy charge-induced voltage alteration

    DOE Patents [OSTI]

    Cole, E.I. Jr.

    1996-06-04

    A scanning electron microscope apparatus and method are described for detecting and imaging open-circuit defects in an integrated circuit (IC). The invention uses a low-energy high-current focused electron beam that is scanned over a device surface of the IC to generate a charge-induced voltage alteration (CIVA) signal at the location of any open-circuit defects. The low-energy CIVA signal may be used to generate an image of the IC showing the location of any open-circuit defects. A low electron beam energy is used to prevent electrical breakdown in any passivation layers in the IC and to minimize radiation damage to the IC. The invention has uses for IC failure analysis, for production-line inspection of ICs, and for qualification of ICs. 5 figs.

  4. Integrated circuit failure analysis by low-energy charge-induced voltage alteration

    DOE Patents [OSTI]

    Cole, Jr., Edward I. (2116 White Cloud St., NE., Albuquerque, NM 87112)

    1996-01-01

    A scanning electron microscope apparatus and method are described for detecting and imaging open-circuit defects in an integrated circuit (IC). The invention uses a low-energy high-current focused electron beam that is scanned over a device surface of the IC to generate a charge-induced voltage alteration (CIVA) signal at the location of any open-circuit defects. The low-energy CIVA signal may be used to generate an image of the IC showing the location of any open-circuit defects. A low electron beam energy is used to prevent electrical breakdown in any passivation layers in the IC and to minimize radiation damage to the IC. The invention has uses for IC failure analysis, for production-line inspection of ICs, and for qualification of ICs.

  5. Charge density stabilised local electron spin pair states in insulating polymers

    SciTech Connect (OSTI)

    Serra, S.; Dissado, L. A.

    2014-12-14

    A model is presented that addresses the energy stability of localized electron states in insulating polymers with respect to delocalized free electron-like states at variable charge densities. The model was derived using an effective Hamiltonian for the total energy of electrons trapped in large polarons and spin-paired bipolarons, which includes the electrostatic interaction between charges that occurs when the charge density exceeds the infinite dilution limit. The phase diagram of the various electronic states with respect to the charge density is derived using parameters determined from experimental data for polyethylene, and it is found that a phase transition from excess charge in the form of stable polarons to a stable state of bipolarons with charge?=?2 and spin number S?=?0 is predicted for a charge density between 0.2?C/m{sup 3} and ?2?C/m{sup 3}. This transition is consistent with a change from low mobility charge transport to charge transport in the form of pulses with a mobility orders of magnitude higher that has been observed in several insulating polymers.

  6. Evaluating Electric Vehicle Charging Impacts and Customer Charging...

    Office of Environmental Management (EM)

    in annual sales of plug-in electric vehicles by 2023, which may substantially increase electricity usage and peak demand in high adoption areas. Understanding customer charging...

  7. U.S. Department of Energy's EV Everywhere Workplace Charging Challenge, Mid-Program Review: Employees Plug In

    SciTech Connect (OSTI)

    2015-12-01

    This Program Review takes an unprecedented look at the state of workplace charging in the United States -- a report made possible by U.S. Department of Energy leadership and valuable support from our partners as they share their progress in developing robust workplace charging programs. Through the Workplace Charging Challenge, more than 250 participants are accelerating the development the nation's worksite PEV charging infrastructure and are supporting cleaner, more convenient transportation options within their communities. Challenge partners are currently providing access to PEV charging stations at more than 440 worksites across the country and are influencing countless other organizations to do the same.

  8. Charge noise, spin-orbit coupling, and dephasing of single-spin qubits

    SciTech Connect (OSTI)

    Bermeister, Adam; Keith, Daniel; Culcer, Dimitrie

    2014-11-10

    Quantum dot quantum computing architectures rely on systems in which inversion symmetry is broken, and spin-orbit coupling is present, causing even single-spin qubits to be susceptible to charge noise. We derive an effective Hamiltonian for the combined action of noise and spin-orbit coupling on a single-spin qubit, identify the mechanisms behind dephasing, and estimate the free induction decay dephasing times T{sub 2}{sup *} for common materials such as Si and GaAs. Dephasing is driven by noise matrix elements that cause relative fluctuations between orbital levels, which are dominated by screened whole charge defects and unscreened dipole defects in the substrate. Dephasing times T{sub 2}{sup *} differ markedly between materials and can be enhanced by increasing gate fields, choosing materials with weak spin-orbit, making dots narrower, or using accumulation dots.

  9. Correlation between the electronic structures and diffusion paths of interstitial defects in semiconductors: The case in CdTe

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ma, Jie; Yang, Jihui; Da Silva, J. L.F.; Wei, Su-Huai

    2014-10-30

    Using first-principles calculations, we study the diffusions of interstitial defects Cd, Cu, Te, and Cl in CdTe. We find that the diffusion behavior is strongly correlated with the electronic structure of the interstitial diffuser. For Cd and Cu, because the defect state is the non-degenerated slike state under Td symmetry, the diffusions are almost along the [111] directions between the tetrahedral sites, although the diffusion of Cu shows some deviation due to the s - d coupling. The diffusions of the neutral and charged Cd and Cu follow similar paths. However, for Te and Cl atoms, because the defect statemoreis the degenerated p-like state under Td symmetry, large distortions occur. Therefore, the diffusion paths are very different from those of Cd and Cu interstitials, and depend strongly on the charge states of the interstitial atoms. For Te, we find that the distortion is mostly stabilized by the crystal-field splitting, but for Cl, the exchange splitting plays a more important role.less

  10. Correlation between the electronic structures and diffusion paths of interstitial defects in semiconductors: The case in CdTe

    SciTech Connect (OSTI)

    Ma, Jie; Yang, Jihui; Da Silva, J. L.F.; Wei, Su-Huai

    2014-10-30

    Using first-principles calculations, we study the diffusions of interstitial defects Cd, Cu, Te, and Cl in CdTe. We find that the diffusion behavior is strongly correlated with the electronic structure of the interstitial diffuser. For Cd and Cu, because the defect state is the non-degenerated slike state under Td symmetry, the diffusions are almost along the [111] directions between the tetrahedral sites, although the diffusion of Cu shows some deviation due to the s - d coupling. The diffusions of the neutral and charged Cd and Cu follow similar paths. However, for Te and Cl atoms, because the defect state is the degenerated p-like state under Td symmetry, large distortions occur. Therefore, the diffusion paths are very different from those of Cd and Cu interstitials, and depend strongly on the charge states of the interstitial atoms. For Te, we find that the distortion is mostly stabilized by the crystal-field splitting, but for Cl, the exchange splitting plays a more important role.

  11. Correlation between the electronic structures and diffusion paths of interstitial defects in semiconductors: The case in CdTe

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ma, Jie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Yang, Jihui [National Renewable Energy Lab. (NREL), Golden, CO (United States); Da Silva, J. L.F. [Univ. of Sao Paulo, Sao Carlos (Brazil). Sao Carlos Institute of Chemistry; Wei, Su-Huai [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-10-01

    Using first-principles calculations, we study the diffusions of interstitial defects Cd, Cu, Te, and Cl in CdTe. We find that the diffusion behavior is strongly correlated with the electronic structure of the interstitial diffuser. For Cd and Cu, because the defect state is the non-degenerated slike state under Td symmetry, the diffusions are almost along the [111] directions between the tetrahedral sites, although the diffusion of Cu shows some deviation due to the s - d coupling. The diffusions of the neutral and charged Cd and Cu follow similar paths. However, for Te and Cl atoms, because the defect state is the degenerated p-like state under Td symmetry, large distortions occur. Therefore, the diffusion paths are very different from those of Cd and Cu interstitials, and depend strongly on the charge states of the interstitial atoms. For Te, we find that the distortion is mostly stabilized by the crystal-field splitting, but for Cl, the exchange splitting plays a more important role.

  12. Structural phase transitions and topological defects in ion Coulomb crystals

    SciTech Connect (OSTI)

    Partner, Heather L.; Nigmatullin, Ramil; Burgermeister, Tobias; Keller, Jonas; Pyka, Karsten; Plenio, Martin B.; Retzker, Alex; Zurek, Wojciech Hubert; del Campo, Adolfo; Mehlstaubler, Tanja E.

    2014-11-19

    We use laser-cooled ion Coulomb crystals in the well-controlled environment of a harmonic radiofrequency ion trap to investigate phase transitions and defect formation. Topological defects in ion Coulomb crystals (kinks) have been recently proposed for studies of nonlinear physics with solitons and as carriers of quantum information. Defects form when a symmetry breaking phase transition is crossed non-adiabatically. For a second order phase transition, the Kibble-Zurek mechanism predicts that the formation of these defects follows a power law scaling in the rate of the transition. We demonstrate a scaling of defect density and describe kink dynamics and stability. We further discuss the implementation of mass defects and electric fields as first steps toward controlled kink preparation and manipulation.

  13. Charge, from EM fields only

    E-Print Network [OSTI]

    R. L. Collins

    2007-03-04

    Consider the electric field E about an electron. Its source has been thought a substance called charge, enclosed within a small volume that defines the size of the electron. Scattering experiments find no size at all. Charge is useful, but mysterious. This study concludes that charge is not real. Useful, but not real. Absent real charge, the electric field must look to a different source. We know another electric field, vxB, not sourced by charge. A simple model of the electron, using EM fields only, has been found that generates an electric field vxB very like E. Gauss' law finds the model contains charge, but div vxB cannot find the charge density. The model contains a permanent magnetic flux quantum, configured as a dipole. The dipolar B fields spin around the symmetry axis, accounting for angular momentum. Spin stabilizes the magnetic flux quantum, and creates the vxB electric field. Stability in this model is dynamic. Energy is exchanged between the dipolar magnetic moment and an encircling toroidal displacement current, at the Compton frequency, mc^2/h = 1.24x10^20 Hz. The electric field undulates at this rate, instead of being static like E associated with charge. Absent any real charge, we have to abandon the notion that size of a charged particle is that of a small sack full of charge. The only electric field is vxB, and its source is not charge. What is the size of an electron? Coulomb scattering finds it point-like, but its spinning B fields extend to infinity.

  14. Instantons and the fixed point topological charge in the two-dimensional O(3) {sigma} model

    SciTech Connect (OSTI)

    Blatter, M.; Burkhalter, R.; Hasenfratz, P.; Niedermayer, F.

    1996-01-01

    We define a fixed point topological charge for the two-dimensional O(3) lattice {sigma} model which is free of topological defects. We use this operator in combination with the fixed point action to measure the topological susceptibility for a wide range of correlation lengths. The results strongly suggest that it is not a physical quantity in this model. The procedure, however, can be applied to other asymptotically free theories as well. {copyright} {ital 1996 The American Physical Society.}

  15. Stable Charged Cosmic Strings

    SciTech Connect (OSTI)

    Weigel, H. [Physics Department, Stellenbosch University, Matieland 7602 (South Africa); Quandt, M. [Institute for Theoretical Physics, Tuebingen University, D-72076 Tuebingen (Germany); Graham, N. [Department of Physics, Middlebury College , Middlebury, Vermont 05753 (United States)

    2011-03-11

    We study the quantum stabilization of a cosmic string by a heavy fermion doublet in a reduced version of the standard model. We show that charged strings, obtained by populating fermionic bound state levels, become stable if the electroweak bosons are coupled to a fermion that is less than twice as heavy as the top quark. This result suggests that extraordinarily large fermion masses or unrealistic couplings are not required to bind a cosmic string in the standard model. Numerically we find the most favorable string profile to be a simple trough in the Higgs vacuum expectation value of radius {approx_equal}10{sup -18} m. The vacuum remains stable in our model, because neutral strings are not energetically favored.

  16. Electric Vehicle Smart Charging Infrastructure

    E-Print Network [OSTI]

    Chung, Ching-Yen

    2014-01-01

    technology provides PEV chargers that simultaneously connectall types, from public fast chargers that will relieve rangeto home and garage chargers used for everyday charging. As a

  17. AUTOMATED DEFECT CLASSIFICATION USING AN ARTIFICIAL NEURAL NETWORK

    SciTech Connect (OSTI)

    Chady, T.; Caryk, M. [Szczecin University of Technology, Department of Electrical Engineering (Poland); Piekarczyk, B. [Technic-Control, Szczecin (Poland)

    2009-03-03

    The automated defect classification algorithm based on artificial neural network with multilayer backpropagation structure was utilized. The selected features of flaws were used as input data. In order to train the neural network it is necessary to prepare learning data which is representative database of defects. Database preparation requires the following steps: image acquisition and pre-processing, image enhancement, defect detection and feature extraction. The real digital radiographs of welded parts of a ship were used for this purpose.

  18. Configuration of ripple domains and their topological defects...

    Office of Scientific and Technical Information (OSTI)

    their topological defects formed under local mechanical stress on hexagonal monolayer graphene Citation Details In-Document Search Title: Configuration of ripple domains and their...

  19. Improved, Defect-Free Electrode Materials - Energy Innovation...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and Fuels Vehicles and Fuels Find More Like This Return to Search Improved, Defect-Free Electrode Materials Brookhaven National Laboratory Contact BNL About This Technology...

  20. Multiple Exciton Generation and Charge Extraction in All-Inorganic Nanostructured Solar Cells (DMR-1035468 -SOLAR Collaborative)

    E-Print Network [OSTI]

    Multiple Exciton Generation and Charge Extraction in All-Inorganic Nanostructured Solar Cells (DMR a comparative analysis of the results in relation to PbS NP solar cells (E3) Optimize the charge transport-equilibrium rate equations will be developed to determine the full rate of MEG Mathematical framework (M1) Lanczos

  1. Nonradiative coherent carrier captures and defect reaction at deep-level defects via phonon-kick mechanism

    SciTech Connect (OSTI)

    Wakita, Masaki; Suzuki, Kei; Shinozuka, Yuzo

    2014-02-21

    We simulated the time evolution of electron-lattice coupling mode, and a series of nonradiative carrier captures by a deep-level defect in a semiconductor. For lattice relaxation energy of the order of the band gap, a series of coherent (athermal) electron and hole captures by a defect is possible for high carrier densities, which results in an inflation in the induced lattice vibration, which in turn enhances a defect reaction.

  2. Transporting particulate material

    DOE Patents [OSTI]

    Aldred, Derek Leslie (North Hollywood, CA); Rader, Jeffrey A. (North Hollywood, CA); Saunders, Timothy W. (North Hollywood, CA)

    2011-08-30

    A material transporting system comprises a material transporting apparatus (100) including a material transporting apparatus hopper structure (200, 202), which comprises at least one rotary transporting apparatus; a stationary hub structure (900) constraining and assisting the at least one rotary transporting apparatus; an outlet duct configuration (700) configured to permit material to exit therefrom and comprising at least one diverging portion (702, 702'); an outlet abutment configuration (800) configured to direct material to the outlet duct configuration; an outlet valve assembly from the material transporting system venting the material transporting system; and a moving wall configuration in the material transporting apparatus capable of assisting the material transporting apparatus in transporting material in the material transporting system. Material can be moved from the material transporting apparatus hopper structure to the outlet duct configuration through the at least one rotary transporting apparatus, the outlet abutment configuration, and the outlet valve assembly.

  3. Parity Breaking Transport in Lifshitz Hydrodynamics

    E-Print Network [OSTI]

    Carlos Hoyos; Adiel Meyer; Yaron Oz

    2015-08-31

    We derive the constitutive relations of first order charged hydrodynamics for theories with Lifshitz scaling and broken parity in $2+1$ and $3+1$ spacetime dimensions. In addition to the anomalous (in $3+1$) or Hall (in $2+1$) transport of relativistic hydrodynamics, there is an additional non-dissipative transport allowed by the absence of boost invariance. We analyze the non-relativistic limit and use a phenomenological model of a strange metal to argue that these effects can be measured in principle by using electromagnetic fields with non-zero gradients.

  4. Distinguishing quantum and classical transport through nanostructures

    E-Print Network [OSTI]

    Neill Lambert; Clive Emary; Yueh-Nan Chen; Franco Nori

    2010-08-23

    We consider the question of how to distinguish quantum from classical transport through nanostructures. To address this issue we have derived two inequalities for temporal correlations in nonequilibrium transport in nanostructures weakly coupled to leads. The first inequality concerns local charge measurements and is of general validity; the second concerns the current flow through the device and is relevant for double quantum dots. Violation of either of these inequalities indicates that physics beyond that of a classical Markovian model is occurring in the nanostructure.

  5. Transportation Data Programs:Transportation Energy Data Book...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Transportation Data Programs:Transportation Energy Data Book,Vehicle Technologies Market Report, and VT Fact of the Week Transportation Data Programs:Transportation Energy Data...

  6. Energetics of Defects on Graphene through Fluorination

    SciTech Connect (OSTI)

    Xiao, Jie; Meduri, Praveen; Chen, Honghao; Wang, Zhiguo; Gao, Fei; Hu, Jian Z.; Feng, Ju; Hu, Mary Y.; Dai, Sheng; Brown, Suree; Adcock, Jamie L.; Deng, Zhiqun; Liu, Jun; Graff, Gordon L.; Aksay, Ilhan A.; Zhang, Jiguang

    2014-04-01

    In the present study, we used FGS[5] as the substrate and implemented low temperature (<=150 oC) direct fluorination on graphene sheets. The fluorine content has been modulated to investigate the formation mechanism of different functional groups such as C-F, CF2, O-CF2 and (C=O)F during the fluorination process. The detailed structure and chemical bonds were simulated theoretically and quantified experimentally by using density function theory (DFT) calculations and NMR techniques, respectively. The adjustable power/energy ratio from fluorinated graphene as cathode for primary lithium batteries is also discussed. From a combination of NMR spectroscopy and theoretical calculation, we conclude that the topological defects without oxygen containing groups provide most of the reactive sites to react with F. FGS also contain a small number of COOH groups which contribute for the fluorination reaction. Hydroxyl or epoxy groups contribute to another fraction of the reaction products.

  7. Holographic thermalization of charged operators

    E-Print Network [OSTI]

    Alejandro Giordano; Nicolas E. Grandi; Guillermo A. Silva

    2014-12-26

    We study a light-like charged collapsing shell in AdS-Reissner-Nordstrom spacetime, investigating whether the corresponding Vaidya metric is supported by matter that satisfies the null energy condition. We find that, if the absolute value of the charge decreases during the collapse, energy conditions are fulfilled everywhere in spacetime. On the other hand, if the absolute value of the charge increases, the metric does not satisfy energy conditions in the IR region. Therefore, from the gauge/gravity perspective, this last case is only useful to study the thermalization of the UV degrees of freedom. For all these geometries, we probe the thermalization process with two point correlators of charged operators, finding that the thermalization time grows with the charge of the operator, as well as with the dimension of space.

  8. Stratified charge internal combustion engine

    SciTech Connect (OSTI)

    Skopil, A.O.

    1991-01-01

    This patent describes an internal combustion engine. It comprises: a main cylinder, a main piston within the main cylinder, and means for delivering a combustible charge into the main cylinder; a smaller idle cylinder, and idle piston within the idle cylinder, and means for delivering a combustible charge into the idle cylinder; an ignition passageway leading from the idle cylinder to the main cylinder; and an ignition device within the ignition passageway operable to ignite a compressed charge discharged by the idle cylinder into the ignition passageway. The passageway being positioned to discharge the ignited compressed charge from the idle cylinder into the main cylinder to ignite the compressed charge within the main cylinder.

  9. Defect behavior of polycrystalline solar cell silicon

    SciTech Connect (OSTI)

    Schroder, D.K.; Park, S.H.; Hwang, I.G.; Mohr, J.B.; Hanly, M.P.

    1993-05-01

    The major objective of this study, conducted from October 1988 to September 1991, was to gain an understanding of the behavior of impurities in polycrystalline silicon and the influence of these impurities on solar cell efficiency. The authors studied edge-defined film-fed growth (EFG) and cast poly-Si materials and solar cells. With EFG Si they concentrated on chromium-doped materials and cells to determine the role of Cr on solar cell performance. Cast poly-Si samples were not deliberately contaminated. Samples were characterized by cell efficiency, current-voltage, deep-level transient spectroscopy (DLTS), surface photovoltage (SPV), open-circuit voltage decay, secondary ion mass spectrometry, and Fourier transform infrared spectroscopy measurements. They find that Cr forms Cr-B pairs with boron at room temperature and these pairs dissociate into Cr{sub i}{sup +} and B{sup {minus}} during anneals at 210{degrees}C for 10 min. Following the anneal, Cr-B pairs reform at room temperature with a time constant of 230 h. Chromium forms CrSi{sub 2} precipitates in heavily contaminated regions and they find evidence of CrSi{sub 2} gettering, but a lack of chromium segregation or precipitation to grain boundaries and dislocations. Cr-B pairs have well defined DLTS peaks. However, DLTS spectra of other defects are not well defined, giving broad peaks indicative of defects with a range of energy levels in the band gap. In some high-stress, low-efficiency cast poly-Si they detect SiC precipitates, but not in low-stress, high-efficiency samples. SPV measurements result in nonlinear SPV curves in some materials that are likely due to varying optical absorption coefficients due to locally varying stress in the material.

  10. Ultrafast Charge Separation and Nongeminate Electron-Hole Recombination in Organic Photovoltaics

    E-Print Network [OSTI]

    Samuel L Smith; Alex W Chin

    2014-06-04

    The mechanism of electron-hole separation in organic solar cells is currently hotly debated. Recent experimental work suggests that these charges can separate on extremely short timescales (<100 fs). This can be understood in terms of delocalised transport within fullerene aggregates, which is thought to emerge on short timescales before vibronic relaxation induces polaron formation. However, in the optimal heterojunction morphology, electrons and holes will often re-encounter each other before reaching the electrodes. If such charges trap and cannot separate, then device efficiency will suffer. Here we extend the theory of ultrafast charge separation to incorporate polaron formation, and find that the same delocalised transport used to explain ultrafast charge separation can account for the suppression of nongeminate recombination in the best devices.

  11. Asymptotic Expansions of Defective Renewal Equations with Applications to Perturbed

    E-Print Network [OSTI]

    Blanchet, Jose H.

    Asymptotic Expansions of Defective Renewal Equations with Applications to Perturbed Risk Models. These expansions are applied to the analysis of Processor Sharing queues and perturbed risk models, and yield Introduction A defective renewal equation for a function ap () takes the form ap (t) = bp (t) + (1 - p) [0,t

  12. Fluctuations from edge defects in superconducting resonators A. Megrant,1

    E-Print Network [OSTI]

    Martinis, John M.

    Fluctuations from edge defects in superconducting resonators C. Neill,1 A. Megrant,1 R. Barends,1 August 2013) Superconducting resonators, used in astronomy and quantum computation, couple strongly to microscopic two-level defects. We monitor the microwave response of superconducting resonators and observe

  13. Simple intrinsic defects in InAs : numerical predictions.

    SciTech Connect (OSTI)

    Schultz, Peter Andrew

    2013-03-01

    This Report presents numerical tables summarizing properties of intrinsic defects in indium arsenide, InAs, as computed by density functional theory using semi-local density functionals, intended for use as reference tables for a defect physics package in device models.

  14. Measuring Point Defect Density in Individual Carbon Nanotubes Using

    E-Print Network [OSTI]

    Hitchcock, Adam P.

    Defects are known to reduce mechanical strength and Young modulus of the CNT and disrupt their electrical, and bending of the basal planes. Prolonged ex- posure shrinks MWCNTs and eventually re- moves their central not quantitative or show limited spatial resolution. In this paper, we demonstrate a new method to visualize defect

  15. Inflaton fluctuations in the presence of cosmological defects

    E-Print Network [OSTI]

    Hing-Tong Cho; Kin-Wang Ng; I-Chin Wang

    2014-10-06

    We study quantum fluctuations of a free massless scalar field during inflation in the presence of a point, line, or plane defect such as a black hole, cosmic string, or domain wall, using a perturbative expansion in powers of small defect parameters. We provide results for the scalar two-point correlation functions that show explicitly a small violation of translational invariance during inflation.

  16. Erosion and Optimal Transport

    E-Print Network [OSTI]

    Birnir, Bjorn; Rowlett, Julie

    2010-01-01

    383 pp. EROSION AND OPTIMAL TRANSPORT [23] I. Ekeland and T.and D. Simons, Sediment transport capacity of overland ?ow,measure spaces via optimal transport, Ann. of Math. (2),

  17. Spin from defects in two-dimensional quantum field theory

    E-Print Network [OSTI]

    Sebastian Novak; Ingo Runkel

    2015-06-24

    We build two-dimensional quantum field theories on spin surfaces starting from theories on oriented surfaces with networks of topological defect lines and junctions. The construction uses a combinatorial description of the spin structure in terms of a triangulation equipped with extra data. The amplitude for the spin surfaces is defined to be the amplitude for the underlying oriented surface together with a defect network dual to the triangulation. Independence of the triangulation and of the other choices follows if the line defect and junctions are obtained from a Delta-separable Frobenius algebra with involutive Nakayama automorphism in the monoidal category of topological defects. For rational conformal field theory we can give a more explicit description of the defect category, and we work out two examples related to free fermions in detail: the Ising model and the so(n) WZW model at level 1.

  18. Spin from defects in two-dimensional quantum field theory

    E-Print Network [OSTI]

    Novak, Sebastian

    2015-01-01

    We build two-dimensional quantum field theories on spin surfaces starting from theories on oriented surfaces with networks of topological defect lines and junctions. The construction uses a combinatorial description of the spin structure in terms of a triangulation equipped with extra data. The amplitude for the spin surfaces is defined to be the amplitude for the underlying oriented surface together with a defect network dual to the triangulation. Independence of the triangulation and of the other choices follows if the line defect and junctions are obtained from a Delta-separable Frobenius algebra with involutive Nakayama automorphism in the monoidal category of topological defects. For rational conformal field theory we can give a more explicit description of the defect category, and we work out two examples related to free fermions in detail: the Ising model and the so(n) WZW model at level 1.

  19. Eddy Current Testing for Detecting Small Defects in Thin Films

    SciTech Connect (OSTI)

    Obeid, Simon; Tranjan, Farid M. [Electrical and Computer Engineering Department, UNCC (United States); Dogaru, Teodor [Albany Instruments, 426-O Barton Creek, Charlotte, NC 28262 (United States)

    2007-03-21

    Presented here is a technique of using Eddy Current based Giant Magneto-Resistance sensor (GMR) to detect surface and sub-layered minute defects in thin films. For surface crack detection, a measurement was performed on a copper metallization of 5-10 microns thick. It was done by scanning the GMR sensor on the surface of the wafer that had two scratches of 0.2 mm, and 2.5 mm in length respectively. In another experiment, metal coatings were deposited over the layers containing five defects with known lengths such that the defects were invisible from the surface. The limit of detection (resolution), in terms of defect size, of the GMR high-resolution Eddy Current probe was studied using this sample. Applications of Eddy Current testing include detecting defects in thin film metallic layers, and quality control of metallization layers on silicon wafers for integrated circuits manufacturing.

  20. Nonlinear beam deflection in photonic lattices with negative defects

    SciTech Connect (OSTI)

    Wang Jiandong [College of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China); Ye Zhuoyi; Lou Cibo [TEDA Applied Physical School, Nankai University, Tianjin 300457 (China); Miller, Alexandra; Zhang Peng [Department of Physics and Astronomy, San Francisco State University, San Francisco, California 94132 (United States); Hu Yi; Chen Zhigang [TEDA Applied Physical School, Nankai University, Tianjin 300457 (China); Department of Physics and Astronomy, San Francisco State University, San Francisco, California 94132 (United States); Yang Jianke [Department of Mathematics and Statistics, University of Vermont, Burlington, Vermont 05401 (United States)

    2011-03-15

    We demonstrate both theoretically and experimentally that a nonlinear beam can be reflected by a negative defect in a photonic lattice if the incident angle is below a threshold value. Above this threshold angle, the beam simply passes through the defect. This phenomenon occurs in both one- and two-dimensional photonic lattices, and it provides a way to use the incident angle to control beam propagation in a lattice network. If the defect is absent or positive, no evident transition from reflection to transmission occurs. These nonlinear phenomena are also compared with linear nondiffracting-beam propagation in a photonic lattice with a defect, and both similarities and differences are observed. In addition, some important features in linear and nonlinear beam propagations are explained analytically by using a linear model with a delta-function defect.

  1. Charge-pump voltage converter

    DOE Patents [OSTI]

    Brainard, John P. (Albuquerque, NM); Christenson, Todd R. (Albuquerque, NM)

    2009-11-03

    A charge-pump voltage converter for converting a low voltage provided by a low-voltage source to a higher voltage. Charge is inductively generated on a transfer rotor electrode during its transit past an inductor stator electrode and subsequently transferred by the rotating rotor to a collector stator electrode for storage or use. Repetition of the charge transfer process leads to a build-up of voltage on a charge-receiving device. Connection of multiple charge-pump voltage converters in series can generate higher voltages, and connection of multiple charge-pump voltage converters in parallel can generate higher currents. Microelectromechanical (MEMS) embodiments of this invention provide a small and compact high-voltage (several hundred V) voltage source starting with a few-V initial voltage source. The microscale size of many embodiments of this invention make it ideally suited for MEMS- and other micro-applications where integration of the voltage or charge source in a small package is highly desirable.

  2. Transporting Hazardous Materials

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Transporting Hazardous Materials The procedures given below apply to all materials that are considered to be hazardous by the U.S. Department of Transportation (DOT). Consult your...

  3. Sustainability and Transport

    E-Print Network [OSTI]

    Gilbert, Richard

    2006-01-01

    2005. Integrating Sustainability into the Trans- portationTHOUGHT PIECE Sustainability and Transport by Richardof the concept of sustainability to transport planning. In

  4. Lubrication by charged polymers , Suzanne Giasson2

    E-Print Network [OSTI]

    Klein, Jacob

    .............................................................. Lubrication by charged polymers Uri lubricants between sliding charged surfaces8 . Here we show that brushes of charged polymers (polyelectro- lytes) attached to surfaces rubbing across an aqueous medium result in superior lubrication compared

  5. Efficient wireless charging with gallium nitride FETs

    E-Print Network [OSTI]

    Yeh, Theresa (Theresa I.)

    2014-01-01

    Though wireless charging is more convenient than traditional wired charging methods, it is currently less efficient. This not only wastes power but can also result in a longer charging time. Improving the efficiency of ...

  6. Charge Diagnostics for Laser Plasma Accelerators

    E-Print Network [OSTI]

    Nakamura, K.

    2011-01-01

    electron spectrometer [24] before sending the e-beam to charge diagnostics,electron beams from the laser plasma accelerator, a comprehensive study of charge diagnosticselectron spectrom- eter was turned off to send e-beams to charge diagnostics.

  7. Determination of Electrochemical Performance and Thermo-Mechanical-Chemical Stability of SOFCs from Defect Modeling

    SciTech Connect (OSTI)

    Eric Wachsman; Keith L. Duncan

    2006-09-30

    This research was focused on two distinct but related issues. The first issue concerned using defect modeling to understand the relationship between point defect concentration and the electrochemical, thermo-chemical and mechano-chemical properties of typical solid oxide fuel cell (SOFC) materials. The second concerned developing relationships between the microstructural features of SOFC materials and their electrochemical performance. To understand the role point defects play in ceramics, a coherent analytical framework was used to develop expressions for the dependence of thermal expansion and elastic modulus on point defect concentration in ceramics. These models, collectively termed the continuum-level electrochemical model (CLEM), were validated through fits to experimental data from electrical conductivity, I-V characteristics, elastic modulus and thermo-chemical expansion experiments for (nominally pure) ceria, gadolinia-doped ceria (GDC) and yttria-stabilized zirconia (YSZ) with consistently good fits. The same values for the material constants were used in all of the fits, further validating our approach. As predicted by the continuum-level electrochemical model, the results reveal that the concentration of defects has a significant effect on the physical properties of ceramic materials and related devices. Specifically, for pure ceria and GDC, the elastic modulus decreased while the chemical expansion increased considerably in low partial pressures of oxygen. Conversely, the physical properties of YSZ remained insensitive to changes in oxygen partial pressure within the studied range. Again, the findings concurred exactly with the predictions of our analytical model. Indeed, further analysis of the results suggests that an increase in the point defect content weakens the attractive forces between atoms in fluorite-structured oxides. The reduction treatment effects on the flexural strength and the fracture toughness of pure ceria were also evaluated at room temperature. The results reveal that the flexural strength decreases significantly after heat treatment in very low oxygen partial pressure environments; however, in contrast, fracture toughness is increased by 30-40% when the oxygen partial pressure was decreased to 10{sup -20} to 10{sup -22} atm range. Fractographic studies show that microcracks developed at 800 oC upon hydrogen reduction are responsible for the decreased strength. To understand the role of microstructure on electrochemical performance, electrical impedance spectra from symmetric LSM/YSZ/LSM cells was de-convoluted to obtain the key electrochemical components of electrode performance, namely charge transfer resistance, surface diffusion of reactive species and bulk gas diffusion through the electrode pores. These properties were then related to microstructural features, such as triple-phase boundary length and tortuosity. From these experiments we found that the impedance due to oxygen adsorption obeys a power law with pore surface area, while the impedance due to charge transfer is found to obey a power-law with respect to triple phase boundary length. A model based on kinetic theory explaining the power-law relationships observed was then developed. Finally, during our EIS work on the symmetric LSM/YSZ/LSM cells a technique was developed to improve the quality of high-frequency impedance data and their subsequent de-convolution.

  8. Effect of charge carrier relaxation during hopping process on electroluminescence in organic solids

    E-Print Network [OSTI]

    Arunandan Kumar; Priyanka Tyagi; Ritu Srivastava; M. N. Kamalasanan

    2014-10-03

    Energetic disorder in disordered organic solids has been found to alter their physical parameters. Here, we have demonstrated, by means of Monte-Carlo simulation and experiments, that the electroluminescence (EL) spectrum is dependent on energetic disorder. This dependence has been attributed to the charge carrier relaxation during hopping process. The dependence of EL spectrum on energetic disorder makes it temperature dependent and temperature dependence has been found to vary with energetic disorder in a variety of materials. The simulation has been performed by taking the relaxation of charge carriers via transport energy in the Gaussian density of states. An analytical equation was established for spectral shift as a function of transport energy.

  9. Operating Experience Level 3: Radcalc V4.1 Software Defect |...

    Office of Environmental Management (EM)

    Operating Experience Level 3: Radcalc V4.1 Software Defect Operating Experience Level 3: Radcalc V4.1 Software Defect September 6, 2011 OE-3 2011-01: Radcalc V4.1 Software Defect...

  10. Clifford Residues and Charge Quantization

    E-Print Network [OSTI]

    Marcus S. Cohen

    2002-07-26

    We derive the quantization of action, particle number, and electric charge in a Lagrangian spin bundle over M equivalent M_# union D_J, Penrose's conformal compactification of Minkowsky space, with the world tubes of massive particles removed.

  11. Electrokinetic concentration of charged molecules

    DOE Patents [OSTI]

    Singh, Anup K. (Berkeley, CA); Neyer, David W. (Castro Valley, CA); Schoeniger, Joseph S. (Oakland, CA); Garguilo, Michael G. (Livermore, CA)

    2002-01-01

    A method for separating and concentrating charged species from uncharged or neutral species regardless of size differential. The method uses reversible electric field induced retention of charged species, that can include molecules and molecular aggregates such as dimers, polymers, multimers, colloids, micelles, and liposomes, in volumes and on surfaces of porous materials. The retained charged species are subsequently quantitatively removed from the porous material by a pressure driven flow that passes through the retention volume and is independent of direction thus, a multi-directional flow field is not required. Uncharged species pass through the system unimpeded thus effecting a complete separation of charged and uncharged species and making possible concentration factors greater than 1000-fold.

  12. Mapping Particle Charges in Battery Electrodes

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    battery charging and discharging. Researchers first charged commercial-grade battery cells to 50% full in 30 minutes, mimicking real world conditions. Then, the battery cell...

  13. A Spintronic Semiconductor with Selectable Charge Carriers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A Spintronic Semiconductor with Selectable Charge Carriers A Spintronic Semiconductor with Selectable Charge Carriers Print Wednesday, 28 August 2013 00:00 Accentuating the...

  14. EV Everywhere Grand Challenge - Charging Infrastructure Enabling...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Charging Infrastructure Enabling Flexible EV Design EV Everywhere Grand Challenge - Charging Infrastructure Enabling Flexible EV Design Presentation given at the EV Everywhere...

  15. EV Everywhere Consumer Acceptance and Charging Infrastructure...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    E Breakout Report EV Everywhere Consumer Acceptance and Charging Infrastructure Workshop: Charging Infrastructure Group E Breakout Report Breakout session presentation for the EV...

  16. Bringing Your Workplace Charging Story to Life

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    charging workshops * Other community events 10 Shannon.shea@ee.doe.gov http:energy.goveerevehiclesvehicle-technologies-office-ev-everywhere- workplace-charging-challenge 11...

  17. Workplace Charging Challenge Partner: Vermont Energy Investment...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    More Information VEIC's Mission Workplace Charging News June 23, 2014 VEIC now an EV Everywhere Workplace Charging Challenge Partner The use of Electric Vehicles (EVs) is...

  18. Workplace Charging Challenge Partner: Purchase College, State...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Purchase College, State University of New York Workplace Charging Challenge Partner: Purchase College, State University of New York Workplace Charging Challenge Partner: Purchase...

  19. Mapping Particle Charges in Battery Electrodes

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Mapping Particle Charges in Battery Electrodes Mapping Particle Charges in Battery Electrodes Print Friday, 26 July 2013 14:18 The deceivingly simple appearance of batteries masks...

  20. Final Technical Report for DE-SC0001878 [Theory and Simulation of Defects in Oxide Materials

    SciTech Connect (OSTI)

    Chelikowsky, James R.

    2014-04-14

    We explored a wide variety of oxide materials and related problems, including materials at the nanoscale and generic problems associated with oxide materials such as the development of more efficient computational tools to examine these materials. We developed and implemented methods to understand the optical and structural properties of oxides. For ground state properties, our work is predominantly based on pseudopotentials and density functional theory (DFT), including new functionals and going beyond the local density approximation (LDA): LDA+U. To study excited state properties (quasiparticle and optical excitations), we use time dependent density functional theory, the GW approach, and GW plus Bethe-Salpeter equation (GW-BSE) methods based on a many-body Green function approaches. Our work focused on the structural, electronic, optical and magnetic properties of defects (such as oxygen vacancies) in hafnium oxide, titanium oxide (both bulk and clusters) and related materials. We calculated the quasiparticle defect states and charge transition levels of oxygen vacancies in monoclinic hafnia. we presented a milestone G0W0 study of two of the crystalline phases of dye-sensitized TiO{sub 2} clusters. We employed hybrid density functional theory to examine the electronic structure of sexithiophene/ZnO interfaces. To identify the possible effect of epitaxial strain on stabilization of the ferromagnetic state of LaCoO{sub 3} (LCO), we compare the total energy of the magnetic and nonmagnetic states of the strained theoretical bulk structure.

  1. Junction Transport in Epitaxial Film Silicon Heterojunction Solar Cells

    SciTech Connect (OSTI)

    Young, D. L.; Li, J. V.; Teplin, C. W.; Stradins, P.; Branz, H. M.

    2011-01-01

    We report our progress toward low-temperature HWCVD epitaxial film silicon solar cells on inexpensive seed layers, with a focus on the junction transport physics exhibited by our devices. Heterojunctions of i/p hydrogenated amorphous Si (a-Si) on our n-type epitaxial crystal Si on n{sup ++} Si wafers show space-charge-region recombination, tunneling or diffusive transport depending on both epitaxial Si quality and the applied forward voltage.

  2. Junction Transport in Epitaxial Film Silicon Heterojunction Solar Cells: Preprint

    SciTech Connect (OSTI)

    Young, D. L.; Li, J. V.; Teplin, C. W.; Stradins, P.; Branz, H. M.

    2011-07-01

    We report our progress toward low-temperature HWCVD epitaxial film silicon solar cells on inexpensive seed layers, with a focus on the junction transport physics exhibited by our devices. Heterojunctions of i/p hydrogenated amorphous Si (a-Si) on our n-type epitaxial crystal Si on n++ Si wafers show space-charge-region recombination, tunneling or diffusive transport depending on both epitaxial Si quality and the applied forward voltage.

  3. AVTA: Bidirectional Fast Charging Report

    Broader source: Energy.gov [DOE]

    The Vehicle Technologies Office's Advanced Vehicle Testing Activity carries out testing on a wide range of advanced vehicles and technologies on dynamometers, closed test tracks, and on-the-road. These results provide benchmark data that researchers can use to develop technology models and guide future research and development. The following report is an analysis of bi-directional fast charging, as informed by the AVTA's testing on plug-in electric vehicle charging equipment. This research was conducted by Idaho National Laboratory.

  4. Nematic cells with defect-patterned alignment layers

    E-Print Network [OSTI]

    Adam S. Backer; A. C. Callan-Jones; Robert A. Pelcovits

    2007-08-29

    Using Monte Carlo simulations of the Lebwohl--Lasher model we study the director ordering in a nematic cell where the top and bottom surfaces are patterned with a lattice of $\\pm 1$ point topological defects of lattice spacing $a$. We find that the nematic order depends crucially on the ratio of the height of the cell $H$ to $a$. When $H/a \\gtrsim 0.9$ the system is very well--ordered and the frustration induced by the lattice of defects is relieved by a network of half--integer defect lines which emerge from the point defects and hug the top and bottom surfaces of the cell. When $H/a \\lesssim 0.9$ the system is disordered and the half--integer defect lines thread through the cell joining point defects on the top and bottom surfaces. We present a simple physical argument in terms of the length of the defect lines to explain these results. To facilitate eventual comparison with experimental systems we also simulate optical textures and study the switching behavior in the presence of an electric field.

  5. A Graphene Quantum Dot with a Single Electron Transistor as Integrated Charge Sensor

    E-Print Network [OSTI]

    Ling-Jun Wang; Gang Cao; Tao Tu; Hai-Ou Li; Cheng Zhou; Xiao-Jie Hao; Zhan Su; Guang-Can Guo; Guo-Ping Guo; Hong-Wen Jiang

    2010-08-28

    We have developed an etching process to fabricate a quantum dot and a nearby single electron transistor as a charge detector in a single layer graphene. The high charge sensitivity of the detector is used to probe Coulomb diamonds as well as excited spectrum in the dot, even in the regime where the current through the quantum dot is too small to be measured by conventional transport means. The graphene based quantum dot and integrated charge sensor serve as an essential building block to form a solid-state qubit in a nuclear-spin-free quantum world.

  6. Transport Equations Thomas Hillen

    E-Print Network [OSTI]

    Hillen, Thomas

    Transport Equations Thomas Hillen supported by NSERC University of Alberta, Edmonton Transport V , V compact and symmetric. Transport Equations p.2/33 #12;Directed Movement The equation pt(t, x of v. Transport Equations p.3/33 #12;With Directional Changes : turning rate. T(v, v ): probability

  7. Motor Transport Co.

    E-Print Network [OSTI]

    Unknown

    2011-09-05

    METROPOLITAN TRANSPORTATION PLAN Prepared by: The Longview Metropolitan Planning Organization In cooperation with: o City of Longview o City of White Oak o Gregg County o Harrison County o Texas Department of Transportation o U.S. Department... of Transportation o Federal Highway Administration o Federal Transit Administration Adopted November 12, 2009 TRANSPORTATION 2035 TABLE OF CONTENTS INTRODUCTION...

  8. Modeling and experimental characterization of stepped and v-shaped (311) defects in silicon

    SciTech Connect (OSTI)

    Marqus, Luis A. Aboy, Mara; Dudeck, Karleen J.; Botton, Gianluigi A.; Knights, Andrew P.; Gwilliam, Russell M.

    2014-04-14

    We propose an atomistic model to describe extended (311) defects in silicon. It is based on the combination of interstitial and bond defect chains. The model is able to accurately reproduce not only planar (311) defects but also defect structures that show steps, bends, or both. We use molecular dynamics techniques to show that these interstitial and bond defect chains spontaneously transform into extended (311) defects. Simulations are validated by comparing with precise experimental measurements on actual (311) defects. The excellent agreement between the simulated and experimentally derived structures, regarding individual atomic positions and shape of the distinct structural (311) defect units, provides strong evidence for the robustness of the proposed model.

  9. Accounting for Localized Defects in the Optoelectronic Design of Thin-Film Solar Cells

    E-Print Network [OSTI]

    Deceglie, Michael G.

    2014-01-01

    Accounting for Localized Defects in the OptoelectronicH solar cells. Explicitly accounting for local variations inthe importance of accounting for defect geometry, and that

  10. Probing graphene defects and estimating graphene quality with optical microscopy

    SciTech Connect (OSTI)

    Lai, Shen [SKKU Advanced Institute of Nanotechnology (SAINT), Suwon 440-746 (Korea, Republic of); Center for Human Interface Nanotechnology (HINT), Suwon 440-746 (Korea, Republic of); Kyu Jang, Sung [SKKU Advanced Institute of Nanotechnology (SAINT), Suwon 440-746 (Korea, Republic of); Jae Song, Young, E-mail: yjsong@skku.edu [SKKU Advanced Institute of Nanotechnology (SAINT), Suwon 440-746 (Korea, Republic of); Department of Physics, Sungkyunkwan University (SKKU), Suwon 440-746 (Korea, Republic of); Lee, Sungjoo, E-mail: leesj@skku.edu [SKKU Advanced Institute of Nanotechnology (SAINT), Suwon 440-746 (Korea, Republic of); Center for Human Interface Nanotechnology (HINT), Suwon 440-746 (Korea, Republic of); College of Information and Communication Engineering, Sungkyunkwan University (SKKU), Suwon 440-746 (Korea, Republic of)

    2014-01-27

    We report a simple and accurate method for detecting graphene defects that utilizes the mild, dry annealing of graphene/Cu films in air. In contrast to previously reported techniques, our simple approach with optical microscopy can determine the density and degree of dislocation of defects in a graphene film without inducing water-related damage or functionalization. Scanning electron microscopy, confocal Raman and atomic force microscopy, and X-ray photoelectron spectroscopy analysis were performed to demonstrate that our nondestructive approach to characterizing graphene defects with optimized thermal annealing provides rapid and comprehensive determinations of graphene quality.

  11. Introduction Transport in disordered graphene

    E-Print Network [OSTI]

    Fominov, Yakov

    Introduction Transport in disordered graphene Summary Ballistic transport in disordered graphene P, Gornyi, Mirlin Ballistic transport in disordered graphene #12;Introduction Transport in disordered graphene Summary Outline 1 Introduction Model Experimental motivation Transport in clean graphene 2

  12. Spectroscopy of Charge Carriers and Traps in Field-Doped Single Crystal Organic Semiconductors

    SciTech Connect (OSTI)

    Zhu, Xiaoyang

    2014-12-10

    The proposed research aims to achieve quantitative, molecular level understanding of charge carriers and traps in field-doped crystalline organic semiconductors via in situ linear and nonlinear optical spectroscopy, in conjunction with transport measurements and molecular/crystal engineering. Organic semiconductors are emerging as viable materials for low-cost electronics and optoelectronics, such as organic photovoltaics (OPV), organic field effect transistors (OFETs), and organic light emitting diodes (OLEDs). Despite extensive studies spanning many decades, a clear understanding of the nature of charge carriers in organic semiconductors is still lacking. It is generally appreciated that polaron formation and charge carrier trapping are two hallmarks associated with electrical transport in organic semiconductors; the former results from the low dielectric constants and weak intermolecular electronic overlap while the latter can be attributed to the prevalence of structural disorder. These properties have lead to the common observation of low charge carrier mobilities, e.g., in the range of 10-5 - 10-3 cm2/Vs, particularly at low carrier concentrations. However, there is also growing evidence that charge carrier mobility approaching those of inorganic semiconductors and metals can exist in some crystalline organic semiconductors, such as pentacene, tetracene and rubrene. A particularly striking example is single crystal rubrene (Figure 1), in which hole mobilities well above 10 cm2/Vs have been observed in OFETs operating at room temperature. Temperature dependent transport and spectroscopic measurements both revealed evidence of free carriers in rubrene. Outstanding questions are: what are the structural features and physical properties that make rubrene so unique? How do we establish fundamental design principles for the development of other organic semiconductors of high mobility? These questions are critically important but not comprehensive, as the nature of charge carriers is known to evolve as the carrier concentration increases, due to the presence of intrinsic disorder in organic semiconductors. Thus, a complementary question is: how does the nature of charge transport change as a function of carrier concentration?

  13. Optimization of Ultrasonic Rail-Defect Inspection for Improving Railway Transportation Safety and Efficiency

    E-Print Network [OSTI]

    Barkan, Christopher P.L.

    D. Little (ADL 1996) is used, in which related cause codes were combined into groups based on expert, and several others within the track group. In this paper, a variation of the FRA subgroups developed by Arthur

  14. Transport and Defect Mechanisms in Cuprous Delafossites. 1. Comparison of Hydrothermal and

    E-Print Network [OSTI]

    Poeppelmeier, Kenneth R.

    flat-panel displays, ultraviolet light emitting diodes, heterojunctions for solar cells, and all- oxide are utilized in a variety of commercial applications, such as flat-panel displays, photovoltaic devices there are no commercially viable p-type TCOs. The development of a high figure-of-merit p-type TCO would enable improved

  15. Optimizing Ultrasonic Rail Defect Inspection to Improve Transportation Safety and Efficiency

    E-Print Network [OSTI]

    Barkan, Christopher P.L.

    inspection frequency is a critical decision in railway infrastructure management. The objective of this paper is a high priority for the rail industry and government. The current practice is to periodically inspect to cyclic loading of the rail by the passage of trains (Jeong and Gordon 2009). As rail fatigue fracture

  16. Heavy and Overweight Vehicle Defects Interim Report

    SciTech Connect (OSTI)

    Siekmann, Adam [ORNL; Capps, Gary J [ORNL

    2012-12-01

    The Federal Highway Administration (FHWA), along with the Federal Motor Carrier Safety Administration (FMCSA), has an interest in overweight commercial motor vehicles, how they affect infrastructure, and their impact on safety on the nation s highways. To assist both FHWA and FMCSA in obtaining more information related to this interest, data was collected and analyzed from two separate sources. A large scale nationwide data collection effort was facilitated by the Commercial Vehicle Safety Alliance as part of a special study on overweight vehicles and an additional, smaller set, of data was collected from the state of Tennessee which included a much more detailed set of data. Over a six-month period, 1,873 Level I inspections were performed in 18 different states that volunteered to be a part of this study. Of the 1,873 inspections, a vehicle out-of-service (OOS) violation was found on 44.79% of the vehicles, a rate significantly higher than the national OOS rate of 27.23%. The main cause of a vehicle being placed OOS was brake-related defects, with approximately 30% of all vehicles having an OOS brake violation. Only about 4% of vehicles had an OOS tire violation, and even fewer had suspension and wheel violations. Vehicle weight violations were most common on an axle group as opposed to a gross vehicle weight violation. About two thirds of the vehicles cited with a weight violation were overweight on an axle group with an average amount of weight over the legal limit of about 2,000 lbs. Data collection is scheduled to continue through January 2014, with more potentially more states volunteering to collect data. More detailed data collections similar to the Tennessee data collection will also be performed in multiple states.

  17. Defect reaction network in Si-doped InP : numerical predictions.

    SciTech Connect (OSTI)

    Schultz, Peter Andrew

    2013-10-01

    This Report characterizes the defects in the defect reaction network in silicon-doped, n-type InP deduced from first principles density functional theory. The reaction network is deduced by following exothermic defect reactions starting with the initially mobile interstitial defects reacting with common displacement damage defects in Si-doped InP until culminating in immobile reaction products. The defect reactions and reaction energies are tabulated, along with the properties of all the silicon-related defects in the reaction network. This Report serves to extend the results for intrinsic defects in SAND 2012-3313: %E2%80%9CSimple intrinsic defects in InP: Numerical predictions%E2%80%9D to include Si-containing simple defects likely to be present in a radiation-induced defect reaction sequence.

  18. Electron Beam Guides Engineering of Functional Defects | ornl...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Materials Characterization Electron Beam Guides Engineering of Functional Defects May 20, 2015 Shown is a Z-contrast image of a vacancy-induced inversion domain (highlighted by the...

  19. 2005 May JOM 29 Casting DefectsOverview

    E-Print Network [OSTI]

    Beckermann, Christoph

    2005 May JOM 29 Casting DefectsOverview Casting designs are generally based factors of safety, which leadtoincreasedcomponentweightsand inefficient use of materials. In castings in castings and determine their effect on performance. INTRODUCTION Designers are responsible for the per

  20. Re-entrant Lithium Local Environments and Defect Driven Electrochemist...

    Office of Scientific and Technical Information (OSTI)

    Lithium Local Environments and Defect Driven Electrochemistry of Li- and Mn-Rich Li-Ion Battery Cathodes Citation Details In-Document Search This content will become publicly...

  1. Defect specific maintenance of SG tubes -- How safe is it?

    SciTech Connect (OSTI)

    Cizelj, L.; Mavko, B.; Dvorsek, T. [Jozef Stefan Institute, Ljubljana (Slovenia)

    1997-02-01

    The efficiency of the defect specific plugging criterion for outside diameter stress corrosion cracking at tube support plates is assessed. The efficiency is defined by three parameters: (1) number of plugged tubes, (2) probability of steam generator tube rupture and (3) predicted accidental leak rate through the defects. A probabilistic model is proposed to quantify the probability of tube rupture, while procedures available in literature were used to define the accidental leak rates. The defect specific plugging criterion was then compared to the performance of traditional (45%) plugging criterion using realistic data from Krsko nuclear power plant. Advantages of the defect specific approach over the traditional one are clearly shown. Some hints on the optimization of safe life of steam generator are also given.

  2. Built-In Self Test (BIST) for Realistic Delay Defects

    E-Print Network [OSTI]

    Tamilarasan, Karthik Prabhu

    2012-02-14

    Testing of delay defects is necessary in deep submicron (DSM) technologies. High coverage delay tests produced by automatic test pattern generation (ATPG) can be applied during wafer and package tests, but are difficult ...

  3. Modeling rough energy landscapes in defected condensed matter

    E-Print Network [OSTI]

    Monasterio Velsquez, Paul Rene

    2010-01-01

    This dissertation is a computational and theoretical investigation of the behavior of defected condensed matter and its evolution over long time scales. The thesis provides original contributions to the methodology used ...

  4. New Composite Silicon-Defect Graphene Anode Architecture

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A New Composite Silicon-Defect Graphene Anode Architecture for High Capacity, High-Rate Li-ion Batteries Xin Zhao, Cary Hayner, Mayfair Kung, and Harold Kung, Northwestern...

  5. Method and apparatus for inspecting reflection masks for defects

    DOE Patents [OSTI]

    Bokor, Jeffrey (Oakland, CA); Lin, Yun (Berkeley, CA)

    2003-04-29

    An at-wavelength system for extreme ultraviolet lithography mask blank defect detection is provided. When a focused beam of wavelength 13 nm is incident on a defective region of a mask blank, three possible phenomena can occur. The defect will induce an intensity reduction in the specularly reflected beam, scatter incoming photons into an off-specular direction, and change the amplitude and phase of the electric field at the surface which can be monitored through the change in the photoemission current. The magnitude of these changes will depend on the incident beam size, and the nature, extent and size of the defect. Inspection of the mask blank is performed by scanning the mask blank with 13 nm light focused to a spot a few .mu.m in diameter, while measuring the reflected beam intensity (bright field detection), the scattered beam intensity (dark-field detection) and/or the change in the photoemission current.

  6. Temperature Anisotropies in a Universe with Global Defects

    E-Print Network [OSTI]

    David Coulson

    1994-07-15

    We present a technique of calculating microwave anisotropies from global defects in a reionised universe. We concentrate on angular scales down to one degree where we expect the nongaussianity of the temperature anisotropy in these models to become apparent.

  7. Atomic Scale Details of Defect-Boundary Interactions

    E-Print Network [OSTI]

    Chen, Di

    2014-12-18

    The study is aimed to understand atomic scale details of defect-boundary interactions, which are critical to develop radiation tolerant fuel cladding materials for harsher neutron environments. By means of molecular dynamics simulations, we...

  8. Design and optimization of a defect tolerant processor array

    E-Print Network [OSTI]

    Lakkapragada, Bhavani S

    1995-01-01

    In this thesis we design and optimization of a defect tolerant MIMD processor array, for maximum performance per wafer area, targeted at applications that have a large number of operations per memory word, is described. The optimization includes...

  9. Influence of defects on thermal and mechanical properties of metals

    E-Print Network [OSTI]

    Kamani, Sandeep Kumar

    2009-05-15

    ) and surface defects (grain boundary) using molecular dynamics simulations. Constant stress-constant temperature ensemble with atmospheric pressures is employed. Various properties like average volume, density, potential energy and total energy are obtained...

  10. Mitigation of substrate defects in reticles using multilayer buffer layers

    DOE Patents [OSTI]

    Mirkarimi, Paul B. (Sunol, CA); Bajt, Sasa (Livermore, CA); Stearns, Daniel G. (Los Altos, CA)

    2001-01-01

    A multilayer film is used as a buffer layer to minimize the size of defects on a reticle substrate prior to deposition of a reflective coating on the substrate. The multilayer buffer layer deposited intermediate the reticle substrate and the reflective coating produces a smoothing of small particles and other defects on the reticle substrate. The reduction in defect size is controlled by surface relaxation during the buffer layer growth process and by the degree of intermixing and volume contraction of the materials at the multilayer interfaces. The buffer layers are deposited at near-normal incidence via a low particulate ion beam sputtering process. The growth surface of the buffer layer may also be heated by a secondary ion source to increase the degree of intermixing and improve the mitigation of defects.

  11. Luminescence properties of defects in GaN

    SciTech Connect (OSTI)

    Reshchikov, Michael A.; Morkoc, Hadis [Department of Electrical Engineering and Physics Department, Virginia Commonwealth University, Richmond, Virginia 23284 (United States)

    2005-03-15

    Gallium nitride (GaN) and its allied binaries InN and AIN as well as their ternary compounds have gained an unprecedented attention due to their wide-ranging applications encompassing green, blue, violet, and ultraviolet (UV) emitters and detectors (in photon ranges inaccessible by other semiconductors) and high-power amplifiers. However, even the best of the three binaries, GaN, contains many structural and point defects caused to a large extent by lattice and stacking mismatch with substrates. These defects notably affect the electrical and optical properties of the host material and can seriously degrade the performance and reliability of devices made based on these nitride semiconductors. Even though GaN broke the long-standing paradigm that high density of dislocations precludes acceptable device performance, point defects have taken the center stage as they exacerbate efforts to increase the efficiency of emitters, increase laser operation lifetime, and lead to anomalies in electronic devices. The point defects include native isolated defects (vacancies, interstitial, and antisites), intentional or unintentional impurities, as well as complexes involving different combinations of the isolated defects. Further improvements in device performance and longevity hinge on an in-depth understanding of point defects and their reduction. In this review a comprehensive and critical analysis of point defects in GaN, particularly their manifestation in luminescence, is presented. In addition to a comprehensive analysis of native point defects, the signatures of intentionally and unintentionally introduced impurities are addressed. The review discusses in detail the characteristics and the origin of the major luminescence bands including the ultraviolet, blue, green, yellow, and red bands in undoped GaN. The effects of important group-II impurities, such as Zn and Mg on the photoluminescence of GaN, are treated in detail. Similarly, but to a lesser extent, the effects of other impurities, such as C, Si, H, O, Be, Mn, Cd, etc., on the luminescence properties of GaN are also reviewed. Further, atypical luminescence lines which are tentatively attributed to the surface and structural defects are discussed. The effect of surfaces and surface preparation, particularly wet and dry etching, exposure to UV light in vacuum or controlled gas ambient, annealing, and ion implantation on the characteristics of the defect-related emissions is described.

  12. Equilibria of EV Charging Benny Lutati1

    E-Print Network [OSTI]

    Yeoh, William

    Equilibria of EV Charging Benny Lutati1 , Vadim Levit1 , Tal Grinshpoun2 , and Amnon Meisels1 1 games · EV charging · V2G · Distributed search 1 Introduction Electric Vehicles (EVs) are an important to be charged daily. When parked during office hours, EVs are expected to charge in a well-balanced pattern

  13. Rapid Coarsening of Ion Beam Ripple Patterns by Defect Annihilation

    SciTech Connect (OSTI)

    Hansen, Henri; Messlinger, Sebastian; Stoian, Georgiana [I. Physikalisches Institut, RWTH Aachen, 52056 Aachen (Germany); Redinger, Alex [I. Physikalisches Institut, RWTH Aachen, 52056 Aachen (Germany); II. Physikalisches Institut, Universitaet zu Koeln, 50937 Koeln, Zuelpicher Strasse 77 (Germany); Krug, Joachim [Institut fuer Theoretische Physik, Universitaet zu Koeln, 50937 Koeln, Zuelpicher Strasse 77 (Germany); Michely, Thomas [II. Physikalisches Institut, Universitaet zu Koeln, 50937 Koeln, Zuelpicher Strasse 77 (Germany)

    2009-04-10

    Ripple patterns formed on Pt(111) through grazing incidence ion beam erosion coarsen rapidly. At and below 450 K coarsening of the patterns is athermal and kinetic, unrelated to diffusion and surface free energy. Similar to the situation for sand dunes, coarsening takes place through annihilation reactions of mobile defects in the pattern. The defect velocity derived on the basis of a simple model agrees quantitatively with the velocity of monatomic steps illuminated by the ion beam.

  14. Ultrasonic Tomography for Detecting and Locating Defects in Concrete Structures

    E-Print Network [OSTI]

    White, Joshua

    2012-07-16

    ....................................................... 18 Figure 6 Typical C-scans for simulated defects in shotcrete slabs: Specimens D, E, I, and M ............................................................................................... 19 Figure 7 Clay lump slab construction... and shotcrete s labs. Figs. 5 and 6 delaminations, are shown in Figs. 5 and 6. The images in these figures are representative 19 19 Fig. 6. Typical C-scans for simulated defects in shotcrete slabs: Specimens D (top left), E (top right), I (bottom...

  15. Building model systems to understand Proton-Coupled Electron Transfer in heme : spectroscopic investigation of charge transfer to axially bound diimide acceptors

    E-Print Network [OSTI]

    Hanson, Christina J

    2013-01-01

    Proton-Coupled Electron Transfer (PCET) is an important mechanistic motif in chemistry, which allows for efficient charge transport in many biological systems. We seek to understand how the proton and electron motions are ...

  16. Crystal defect studies using x-ray diffuse scattering

    SciTech Connect (OSTI)

    Larson, B.C.

    1980-01-01

    Microscopic lattice defects such as point (single atom) defects, dislocation loops, and solute precipitates are characterized by local electronic density changes at the defect sites and by distortions of the lattice structure surrounding the defects. The effect of these interruptions of the crystal lattice on the scattering of x-rays is considered in this paper, and examples are presented of the use of the diffuse scattering to study the defects. X-ray studies of self-interstitials in electron irradiated aluminum and copper are discussed in terms of the identification of the interstitial configuration. Methods for detecting the onset of point defect aggregation into dislocation loops are considered and new techniques for the determination of separate size distributions for vacancy loops and interstitial loops are presented. Direct comparisons of dislocation loop measurements by x-rays with existing electron microscopy studies of dislocation loops indicate agreement for larger size loops, but x-ray measurements report higher concentrations in the smaller loop range. Methods for distinguishing between loops and three-dimensional precipitates are discussed and possibilities for detailed studies considered. A comparison of dislocation loop size distributions obtained from integral diffuse scattering measurements with those from TEM show a discrepancy in the smaller sizes similar to that described above.

  17. A HIERARCHY OF EMPIRICAL MODELS OF PLASMA PROFILES AND TRANSPORT

    E-Print Network [OSTI]

    average density, #22; n e (in 10 19 =m 3 ), the absorbed power, P (in MW), the e#11;ective ion charge, ZA HIERARCHY OF EMPIRICAL MODELS OF PLASMA PROFILES AND TRANSPORT Kaya Imre and Kurt S. Riedel New, Oxon, OX14 3EA, UK Abstract Two families of statistical models of increasing statistical complexity

  18. Testimony of Ginger Goodin Transportation Policy Research Center

    E-Print Network [OSTI]

    case implementing, fees based on actual travel as a transportation funding replacement to the fuel tax. These fees go by many different names: Road User Charges (RUC), Mileage-based User Fees (MBUF) and Vehicle-term sustainability of fuel taxes is uncertain. Fuel taxes are levied on a per-gallon basis and have not been raised

  19. MATERIALS WITH ENGINEERED MESOPOROSITY FOR PROGRAMMED MASS TRANSPORT

    E-Print Network [OSTI]

    Braun, Paul

    , artificial photosynthesis and energy storage. This thesis will present work on the transport of molecular electrode. Finally, a model !-bactiophage was developed to study the electromigration of charged molecules porous gold film and a higher surface area than a gold opal. An equivalent circuit model was presented

  20. Turbulence, Transport and the Density Limit in Magnetic Fusion Experiments

    E-Print Network [OSTI]

    Greenwald, Martin

    Program) 3 Magnetic Confinement Takes advantage of the motion of charged particles in a magnetic field) In toroidal devices, plasma is confined by Poloidal magnetic fields #12;DESPITE THE CHALLENGES, PROGRESS HAS AND MAGNETIC CONFINEMENT THE DENSITY LIMIT PROBLEM INTERLUDE ON TRANSPORT AND TURBULENCE TOWARDS

  1. Alternator control for battery charging

    DOE Patents [OSTI]

    Brunstetter, Craig A.; Jaye, John R.; Tallarek, Glen E.; Adams, Joseph B.

    2015-07-14

    In accordance with an aspect of the present disclosure, an electrical system for an automotive vehicle has an electrical generating machine and a battery. A set point voltage, which sets an output voltage of the electrical generating machine, is set by an electronic control unit (ECU). The ECU selects one of a plurality of control modes for controlling the alternator based on an operating state of the vehicle as determined from vehicle operating parameters. The ECU selects a range for the set point voltage based on the selected control mode and then sets the set point voltage within the range based on feedback parameters for that control mode. In an aspect, the control modes include a trickle charge mode and battery charge current is the feedback parameter and the ECU controls the set point voltage within the range to maintain a predetermined battery charge current.

  2. A non-isothermal PEM fuel cell model including two water transport mechanisms in the

    E-Print Network [OSTI]

    Mnster, Westflische Wilhelms-Universitt

    A non-isothermal PEM fuel cell model including two water transport mechanisms in the membrane K Freiburg Germany A dynamic two-phase flow model for proton exchange mem- brane (PEM) fuel cells and the species concentrations. In order to describe the charge transport in the fuel cell the Poisson equations

  3. Transport in inhomogeneous quantum critical fluids and in the Dirac fluid in graphene

    E-Print Network [OSTI]

    -impurity scattering. We use this formalism to compute transport coe cients in the Dirac fluid in clean sampleseaster egg Transport in inhomogeneous quantum critical fluids and in the Dirac fluid in graphene-perturbative in the strength of long wavelength fluctuations in the background charge density of the electronic fluid

  4. NUMERICAL COUPLING OF ELECTRIC CIRCUIT EQUATIONS AND ENERGY-TRANSPORT MODELS FOR SEMICONDUCTORS

    E-Print Network [OSTI]

    Jngel, Ansgar

    NUMERICAL COUPLING OF ELECTRIC CIRCUIT EQUATIONS AND ENERGY-TRANSPORT MODELS FOR SEMICONDUCTORS effects is proposed. The charged particle flow in the semiconductor devices is described by the energy-transport equations for the electrons and the drift-diffusion equations for the holes. The electric circuit is modeled

  5. Battery Electric Vehicle Driving and Charging Behavior Observed Early in The EV Project

    SciTech Connect (OSTI)

    John Smart; Stephen Schey

    2012-04-01

    As concern about society's dependence on petroleum-based transportation fuels increases, many see plug-in electric vehicles (PEV) as enablers to diversifying transportation energy sources. These vehicles, which include plug-in hybrid electric vehicles (PHEV), range-extended electric vehicles (EREV), and battery electric vehicles (BEV), draw some or all of their power from electricity stored in batteries, which are charged by the electric grid. In order for PEVs to be accepted by the mass market, electric charging infrastructure must also be deployed. Charging infrastructure must be safe, convenient, and financially sustainable. Additionally, electric utilities must be able to manage PEV charging demand on the electric grid. In the Fall of 2009, a large scale PEV infrastructure demonstration was launched to deploy an unprecedented number of PEVs and charging infrastructure. This demonstration, called The EV Project, is led by Electric Transportation Engineering Corporation (eTec) and funded by the U.S. Department of Energy. eTec is partnering with Nissan North America to deploy up to 4,700 Nissan Leaf BEVs and 11,210 charging units in five market areas in Arizona, California, Oregon, Tennessee, and Washington. With the assistance of the Idaho National Laboratory, eTec will collect and analyze data to characterize vehicle consumer driving and charging behavior, evaluate the effectiveness of charging infrastructure, and understand the impact of PEV charging on the electric grid. Trials of various revenue systems for commercial and public charging infrastructure will also be conducted. The ultimate goal of The EV Project is to capture lessons learned to enable the mass deployment of PEVs. This paper is the first in a series of papers documenting the progress and findings of The EV Project. This paper describes key research objectives of The EV Project and establishes the project background, including lessons learned from previous infrastructure deployment and PEV demonstrations. One such previous study was a PHEV demonstration conducted by the U.S. Department of Energy's Advanced Vehicle Testing Activity (AVTA), led by the Idaho National Laboratory (INL). AVTA's PHEV demonstration involved over 250 vehicles in the United States, Canada, and Finland. This paper summarizes driving and charging behavior observed in that demonstration, including the distribution of distance driven between charging events, charging frequency, and resulting proportion of operation charge depleting mode. Charging demand relative to time of day and day of the week will also be shown. Conclusions from the PHEV demonstration will be given which highlight the need for expanded analysis in The EV Project. For example, the AVTA PHEV demonstration showed that in the absence of controlled charging by the vehicle owner or electric utility, the majority of vehicles were charged in the evening hours, coincident with typical utility peak demand. Given this baseline, The EV Project will demonstrate the effects of consumer charge control and grid-side charge management on electricity demand. This paper will outline further analyses which will be performed by eTec and INL to documenting driving and charging behavior of vehicles operated in a infrastructure-rich environment.

  6. Secure Transportation Management

    SciTech Connect (OSTI)

    Gibbs, P. W.

    2014-10-15

    Secure Transport Management Course (STMC) course provides managers with information related to procedures and equipment used to successfully transport special nuclear material. This workshop outlines these procedures and reinforces the information presented with the aid of numerous practical examples. The course focuses on understanding the regulatory framework for secure transportation of special nuclear materials, identifying the insider and outsider threat(s) to secure transportation, organization of a secure transportation unit, management and supervision of secure transportation units, equipment and facilities required, training and qualification needed.

  7. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    synthesis (scalable processing) (2) accuracy (1) cathodes (1) charge transport (1) coatings (1) coherence length (1) comparative evaluations (1) defects (1) electrochemical...

  8. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    nanoscience and nanotechnology solar (photovoltaic), solar (fuels), solid state lighting, bio-inspired, electrodes - solar, defects, charge transport, materials and chemistry...

  9. Fano Resonances in Plasmonic Nanoclusters: Geometrical and Chemical...

    Office of Scientific and Technical Information (OSTI)

    77 NANOSCIENCE AND NANOTECHNOLOGY solar (photovoltaic), solar (fuels), solid state lighting, bio-inspired, electrodes - solar, defects, charge transport, materials and chemistry...

  10. Two types of luminescence blinking revealed by spectroelectrochemistry...

    Office of Scientific and Technical Information (OSTI)

    77 NANOSCIENCE AND NANOTECHNOLOGY solar (photovoltaic), solar (fuels), solid state lighting, bio-inspired, electrodes - solar, defects, charge transport, materials and chemistry...

  11. Plexciton Dynamics: Exciton-Plasmon Coupling in a J-Aggregate...

    Office of Scientific and Technical Information (OSTI)

    77 NANOSCIENCE AND NANOTECHNOLOGY solar (photovoltaic); solar (fuels); solid state lighting; bio-inspired; electrodes - solar; defects; charge transport; materials and chemistry...

  12. Near-Unity Quantum Yields of Biexciton Emission from CdSe=CdS...

    Office of Scientific and Technical Information (OSTI)

    77 NANOSCIENCE AND NANOTECHNOLOGY solar (photovoltaic), solar (fuels), solid state lighting, bio-inspired, electrodes - solar, defects, charge transport, materials and chemistry...

  13. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    solar (fuels), photosynthesis (natural and artificial), bio-inspired, hydrogen and fuel cells, electrodes - solar, defects, charge transport, spin dynamics, membrane,...

  14. Electric Charge in Interaction with Magnetically Charged Black Holes

    E-Print Network [OSTI]

    J. H. Kim; Sei-Hoon Moon

    2007-10-02

    We examine the angular momentum of an electric charge e placed at rest outside a dilaton black hole with magnetic charge Q. The electromagnetic angular momentum which is stored in the electromagnetic field outside the black hole shows several common features regardless of the dilaton coupling strength, though the dilaton black holes are drastically different in their spacetime structure depending on it. First, the electromagnetic angular momentum depends on the separation distance between the two objects and changes monotonically from eQ to 0 as the charge goes down from infinity to the horizon, if rotational effects of the black hole are discarded. Next, as the black hole approaches extremality, however, the electromagnetic angular momentum tends to be independent of the distance between the two objects. It is then precisely $eQ$ as in the electric charge and monopole system in flat spacetime. We discuss why these effects are exhibited and argue that the above features are to hold in widely generic settings including black hole solutions in theories with more complicated field contents, by addressing the no hair theorem for black holes and the phenomenon of field expulsion exhibited by extremal black holes.

  15. Water Transport Within the STack: Water Transport Exploratory...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Within the STack: Water Transport Exploratory Studies Water Transport Within the STack: Water Transport Exploratory Studies Part of a 100 million fuel cell award announced by DOE...

  16. Transport Coefficients for Holographic Hydrodynamics at Finite Energy Scale

    E-Print Network [OSTI]

    Xian-Hui Ge; Hong-Qiang Leng; Li Qing Fang; Guo-Hong Yang

    2014-08-19

    We investigate the relations between black hole thermodynamics and holographic transport coefficients in this paper. The formulae for DC conductivity and diffusion coefficient are verified for electrically single-charged black holes. We examine the correctness of the proposed expressions by taking charged dilatonic and single-charged STU black holes as two concrete examples, and compute the flows of conductivity and diffusion coefficient by solving the linear order perturbation equations. We then check the consistence by evaluating the Brown-York tensor at a finite radial position. Finally, we find that the retarded Green functions for the shear modes can be expressed easily in terms of black hole thermodynamic quantities and transport coefficients.

  17. Possible applications of the steering of charged particles by bent single crystals

    SciTech Connect (OSTI)

    Carrigan, R.A. Jr.; Gibson, W.M.; Sun, C.R.; Tsyganov, E.N.

    1981-01-01

    This article reviews some aspects of the steering of charged particles using channeling in bent crystals. Crystal angular and spatial acceptance, deflection dechanneling, and radiation damage are discussed. Examples of possible bent transport, focusing, the possibility of charm particle separated beams, and magnetic moment determination.

  18. Defect studies in low-temperature-grown GaAs

    SciTech Connect (OSTI)

    Bliss, D.E.

    1992-11-01

    High content of excess As is incorporated in GaAs grown by low-temperature molecular-beam-epitaxy (LTMBE). The excess As exists primarily as As antisite defects AsGa and a lesser extent of gallium vacancies V[sub Ga]. The neutral AsGa-related defects were measured by infrared absorption at 1[mu]m. Gallium vacancies, V[sub Ga], was investigated by slow positron annihilation. Dependence of defect contents on doping was studied by Si and Be dopants. No free carriers are generated by n-type or p-type doping up to 10[sup 19] cm[sup [minus]3] Si or Be. Raman data indicate Be occupies Ga substitutional sites but Si atom is not substitutional. Si induces more As[sub Ga] in the layer. As As[sub Ga] increases, photoquenchable As[sub Ga] decreases. Fraction of photoquenchable defects correlates to defects within 3 nearest neighbor separations disrupting the metastability. Annealing reduces neutral As[sub Ga] content around 500C, similar to irradiation damaged and plastically deformed Ga[sub As], as opposed to bulk grown GaAs in which As[sub Ga]-related defects are stable up to 1100C. The lower temperature defect removal is due to V[sub Ga] enhanced diffusion of As[sub Ga] to As precipitates. The supersaturated V[sub GA] and also decreases during annealing. Annealing kinetics for As[sub Ga]-related defects gives 2.0 [plus minus] 0.3 eV and 1.5 [plus minus] 0.3 eV migration enthalpies for the As[sub Ga] and V[sub Ga]. This represents the difference between Ga and As atoms hopping into the vacancy. The non-photoquenchable As[sub Ga]-related defects anneal with an activation energy of 1.1 [plus minus] 0.3eV. Be acceptors can be activated by 800C annealing. Temperature difference between defect annealing and Be activation formation of As[sub Ga]-Be[sub Ga] pairs. Si donors can only be partially activated.

  19. Context-based automated defect classification system using multiple morphological masks

    DOE Patents [OSTI]

    Gleason, Shaun S. (Knoxville, TN); Hunt, Martin A. (Knoxville, TN); Sari-Sarraf, Hamed (Lubbock, TX)

    2002-01-01

    Automatic detection of defects during the fabrication of semiconductor wafers is largely automated, but the classification of those defects is still performed manually by technicians. This invention includes novel digital image analysis techniques that generate unique feature vector descriptions of semiconductor defects as well as classifiers that use these descriptions to automatically categorize the defects into one of a set of pre-defined classes. Feature extraction techniques based on multiple-focus images, multiple-defect mask images, and segmented semiconductor wafer images are used to create unique feature-based descriptions of the semiconductor defects. These feature-based defect descriptions are subsequently classified by a defect classifier into categories that depend on defect characteristics and defect contextual information, that is, the semiconductor process layer(s) with which the defect comes in contact. At the heart of the system is a knowledge database that stores and distributes historical semiconductor wafer and defect data to guide the feature extraction and classification processes. In summary, this invention takes as its input a set of images containing semiconductor defect information, and generates as its output a classification for the defect that describes not only the defect itself, but also the location of that defect with respect to the semiconductor process layers.

  20. Observation of lower to higher bandgap transition of one-dimensional defect modes

    E-Print Network [OSTI]

    Chen, Zhigang

    Observation of lower to higher bandgap transition of one-dimensional defect modes Xiaosheng Wang with a negative defect and observe linear bandgap guidance in such a defect. We show that a defect mode moves from and links 1. J. D. Joannopoulos, R. D. Meade, and J. N. Winn, Photonic Crystals: Molding the Flow of Light

  1. Mechanical properties of carbon nanotubes with vacancies and related defects M. Sammalkorpi,1,

    E-Print Network [OSTI]

    Nordlund, Kai

    mechanical characteris- tics. Likewise, defects may enhance the overall characteris- tics of bundles

  2. Use of relative code churn measures to predict system defect density

    E-Print Network [OSTI]

    Bae, Doo-Hwan

    Use of relative code churn measures to predict system defect density Nachiappan Nagappan and Thomas for potential defects Research goal Create a set of relative code churn measures as early indicators of defects Validate defect prediction power of the measures Code churn Measure of the amount of code change

  3. Systems and methods for forming defects on graphitic materials and curing radiation-damaged graphitic materials

    SciTech Connect (OSTI)

    Ryu, Sunmin; Brus, Louis E.; Steigerwald, Michael L.; Liu, Haitao

    2012-09-25

    Systems and methods are disclosed herein for forming defects on graphitic materials. The methods for forming defects include applying a radiation reactive material on a graphitic material, irradiating the applied radiation reactive material to produce a reactive species, and permitting the reactive species to react with the graphitic material to form defects. Additionally, disclosed are methods for removing defects on graphitic materials.

  4. Midwestern Radioactive Materials Transportation Committee Agenda...

    Office of Environmental Management (EM)

    Midwestern Radioactive Materials Transportation Committee Agenda Midwestern Radioactive Materials Transportation Committee Agenda Midwestern Radioactive Materials Transportation...

  5. Transportation | ornl.gov

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    use of non-petroleum-based fuels through the advancement of bio-based products and natural gas. Developments in energy storage technologies, charging methods, and advanced...

  6. Transportation and its Infrastructure

    E-Print Network [OSTI]

    2007-01-01

    electrical energy if regenerative braking is available (seerecharged only by regenerative braking and engine charging,systems, store regenerative braking energy and to operate

  7. Analysis of electron capture process in charge pumping sequence using time domain measurements

    SciTech Connect (OSTI)

    Hori, Masahiro Watanabe, Tokinobu; Ono, Yukinori; Tsuchiya, Toshiaki

    2014-12-29

    A method for analyzing the electron capture process in the charge pumping (CP) sequence is proposed and demonstrated. The method monitors the electron current in the CP sequence in time domain. This time-domain measurements enable us to directly access the process of the electron capture to the interface defects, which are obscured in the conventional CP method. Using the time-domain measurements, the rise time dependence of the capture process is systematically investigated. We formulate the capture process based on the rate equation and derive an analytic form of the current due to the electron capture to the defects. Based on the formula, the experimental data are analyzed and the capture cross section is obtained. In addition, the time-domain data unveil that the electron capture process completes before the electron channel opens, or below the threshold voltage in a low frequency range of the pulse.

  8. Packaging and Transportation Safety

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1995-09-27

    Establishes safety requirements for the proper packaging and transportation of Department of Energy (DOE) offsite shipments and onsite transfers of hazardous materials and for modal transport. Canceled by DOE 460.1A

  9. Packaging and Transportation Safety

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2010-05-14

    The order establishes safety requirements for the proper packaging and transportation of DOE, including NNSA, offsite shipments and onsite transfers of radioactive and other hazardous materials and for modal transportation. Supersedes DOE O 460.1B.

  10. Sustainability and Transport

    E-Print Network [OSTI]

    Gilbert, Richard

    2006-01-01

    also known there as sustainable mobility. This de?nition wasfor De?ning Sustainable Transport and Mobility. [cited 13Sustainable transporta- tion is de?ned as a means to satisfy current transport and mobility

  11. Transportation Management Workshop: Proceedings

    SciTech Connect (OSTI)

    Not Available

    1993-10-01

    This report is a compilation of discussions presented at the Transportation Management Workshop held in Gaithersburg, Maryland. Topics include waste packaging, personnel training, robotics, transportation routing, certification, containers, and waste classification.

  12. Linear Motor Powered Transportation

    E-Print Network [OSTI]

    Thornton, Richard D.

    This special issue on linear-motor powered transportation covers both supporting technologies and innovative transport systems in various parts of the World, as this technology moves from the lab to commercial operations. ...

  13. Transportation Conference Speakers - 4

    E-Print Network [OSTI]

    Unknown

    2011-08-17

    Laboratory experiments were performed to study and improve longshore sediment transport rate predictions. Measured total longshore transport in the laboratory was approximately three times greater for plunging breakers than spilling breakers. Three...

  14. Transportation Energy Futures Study

    Office of Energy Efficiency and Renewable Energy (EERE)

    Transportation accounts for 71% of total U.S. petroleum consumption and 33% of total greenhouse gas emissions. The Transportation Energy Futures (TEF)study examines underexplored oil-savings and...

  15. Transportation Market Distortions

    E-Print Network [OSTI]

    Litman, Todd

    2006-01-01

    roads and parking facilities is exempt from rent and taxes,road transport relative to rail (which pays rent and taxesroad tolls, parking fees, and Litman, Transportation Market Distortions higher fuel taxes

  16. Introduction to Transportation Planning

    E-Print Network [OSTI]

    Tipple, Brett

    Introduction to Transportation Planning CMP 4710/6710 Fall 2012 3 Credit Hours Room: ARCH 229 of City & Metropolitan Planning; Associate Dean, College of Architecture + Planning; former associate, social equity, fiscal health, and public health. Unfortunately, most transportation planning processes

  17. Transportation Conference Speakers - 1

    E-Print Network [OSTI]

    Unknown

    2011-08-17

    Thiamin transport in Escherichia coli is a model system to establish the tolerance of derivatives for transport into the cell. Since little is known about what types of thiamin derivatives may be successfully taken into the cell through...

  18. Packaging and Transportation Safety

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1995-09-27

    Establishes safety requirements for the proper packaging and transportation of offsite shipments and onsite transfers of hazardous materials andor modal transport. Cancels DOE 1540.2 and DOE 5480.3

  19. Packaging and Transportation Safety

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1996-10-02

    Establishes safety requirements for the proper packaging and transportation of Department of Energy (DOE) offsite shipments and onsite transfers of hazardous materials and for modal transport. Cancels DOE O 460.1.

  20. Biofuels and Transportation

    E-Print Network [OSTI]

    Minnesota, University of

    Biofuels and Transportation Impacts and Uncertainties Some Observations of a Reformed Ethanol and Logistics Symposium 3 Topics Why Biofuels Ethanol Economics Ethanol Transportation Equipment Biofuels? National Security Reduce Imports of oil Peak Oil Replace Fossil Resources

  1. Spin Transport in Semiconductor heterostructures

    SciTech Connect (OSTI)

    Domnita Catalina Marinescu

    2011-02-22

    The focus of the research performed under this grant has been the investigation of spin transport in magnetic semiconductor heterostructures. The interest in these systems is motivated both by their intriguing physical properties, as the physical embodiment of a spin-polarized Fermi liquid, as well as by their potential applications as spintronics devices. In our work we have analyzed several different problems that affect the spin dynamics in single and bi-layer spin-polarized two-dimensional (2D) systems. The topics of interests ranged from the fundamental aspects of the electron-electron interactions, to collective spin and charge density excitations and spin transport in the presence of the spin-orbit coupling. The common denominator of these subjects is the impact at the macroscopic scale of the spin-dependent electron-electron interaction, which plays a much more subtle role than in unpolarized electron systems. Our calculations of several measurable parameters, such as the excitation frequencies of magneto-plasma modes, the spin mass, and the spin transresistivity, propose realistic theoretical estimates of the opposite-spin many-body effects, in particular opposite-spin correlations, that can be directly connected with experimental measurements.

  2. Indianapolis Public Transportation Corporation

    SciTech Connect (OSTI)

    Not Available

    2004-12-01

    Fact sheet describes the National Renewable Energy Laboratory's evaluation of Indianapolis Public Transportation Corporation's (IndyGo's) hybrid electric buses.

  3. Transport coefficients of D1-D5-P system and the membrane paradigm

    E-Print Network [OSTI]

    Yuya Sasai

    2012-01-12

    I discuss a correspondence between string theory and the black hole membrane paradigm in the context of the D1-D5-P system. By using the Kubo formula, I calculate transport coefficients of the effective string model induced by two kinds of minimal scalars. Then, I show that these transport coefficients exactly agree with the corresponding membrane transport coefficients of a five-dimensional near-extremal black hole with three charges.

  4. Stability of charged thin shells

    SciTech Connect (OSTI)

    Eiroa, Ernesto F.; Simeone, Claudio

    2011-05-15

    In this article we study the mechanical stability of spherically symmetric thin shells with charge, in Einstein-Maxwell and Einstein-Born-Infeld theories. We analyze linearized perturbations preserving the symmetry, for shells around vacuum and shells surrounding noncharged black holes.

  5. Controlled Spin Transport in Planar Systems Through Topological Exciton

    E-Print Network [OSTI]

    Kumar Abhinav; Prasanta K. Panigrahi

    2015-07-01

    It is shown that a charge-neutral spin-1 exciton, realizable only in planar systems like graphene, can effectively be used for controlled spin transport in such media. The excitonic bound state is destabilized by quantum fluctuations, characterized by a threshold for excitation and melts in a smooth manner under thermal fluctuations. This planar exciton differs from the conventional ones, as it owes its existence to the topological Chern-Simons (CS) term. The parity and time-reversal violating CS term can arise from quantum effects in systems with parity-breaking mass-gap. The spinning exciton naturally couples to magnetic field, leading to the possibility of controlled spin transport. Being neutral, it is immune to adverse effects, afflicting spin transport by charged fermions.

  6. Limitation of the Open-Circuit Voltage Due to Metastable Intrinsic Defects in Cu(In,Ga)Se2 and Strategies to Avoid These Defects: Preprint

    SciTech Connect (OSTI)

    Lany, S.; Zunger, A.

    2008-05-01

    This paper summarizes using first-principles defect theory to investigate the role of intrinsic point defects in the limitation of the open-circuit voltage (VOC) in Cu(In,Ga)Se2 solar cells.

  7. Parking & Transportation Services Sustainability &

    E-Print Network [OSTI]

    Minnesota, University of

    : 2011 #12;As a long-time leader in the areas of waste abatement, pollution reduction, energy management Metro Commuter Services Infinity Award in recognition of alternative transportation programs. 1996 to maintaining impressive and viable alternative transportation programs. TRANSPORTATION SYSTEM DESIGNS

  8. When Like Charges Attract: Interactions and Dynamics in Charge-Stabilized Colloidal

    E-Print Network [OSTI]

    Grier, David

    When Like Charges Attract: Interactions and Dynamics in Charge-Stabilized Colloidal Suspensions as protein folding, DNA complexation, and the stability of industrial suspensions. Since the goal highly charged colloidal spheres dispersed in simple electrolytes yield several surprises. Isolated pairs

  9. Simulation of radiation-induced defects

    E-Print Network [OSTI]

    Timo Peltola

    2015-09-29

    Mainly due to their outstanding performance the position sensitive silicon detectors are widely used in the tracking systems of High Energy Physics experiments such as the ALICE, ATLAS, CMS and LHCb at LHC, the world's largest particle physics accelerator at CERN, Geneva. The foreseen upgrade of the LHC to its high luminosity (HL) phase (HL-LHC scheduled for 2023), will enable the use of maximal physics potential of the facility. After 10 years of operation the expected fluence will expose the tracking systems at HL-LHC to a radiation environment that is beyond the capacity of the present system design. Thus, for the required upgrade of the all-silicon central trackers extensive measurements and simulation studies for silicon sensors of different designs and materials with sufficient radiation tolerance have been initiated within the RD50 Collaboration. Supplementing measurements, simulations are in vital role for e.g. device structure optimization or predicting the electric fields and trapping in the silicon sensors. The main objective of the device simulations in the RD50 Collaboration is to develop an approach to model and predict the performance of the irradiated silicon detectors using professional software. The first successfully developed quantitative models for radiation damage, based on two effective midgap levels, are able to reproduce the experimentally observed detector characteristics like leakage current, full depletion voltage and charge collection efficiency (CCE). Recent implementations of additional traps at the SiO$_2$/Si interface or close to it have expanded the scope of the experimentally agreeing simulations to such surface properties as the interstrip resistance and capacitance, and the position dependency of CCE for strip sensors irradiated up to $\\sim$$1.5\\times10^{15}$ n$_{\\textrm{eq}}\\textrm{cm}^{-2}$.

  10. Transportation Secure Data Center: Real-World Data for Transportation Planning and Land Use Analysis (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-01-01

    The National Renewable Energy Laboratory (NREL) and the U.S. Department of Transportation (DOT) have launched the free, web-based Transportation Secure Data Center (TSDC). The TSDC (www.nrel.gov/tsdc) preserves respondent anonymity while making vital transportation data available to a broad group of users through secure, online access. The TSDC database provides free-of-charge web-based access to valuable transportation data that can be used for: Transit planning, Travel demand modeling, Homeland Security evacuation planning, Alternative fuel station planning, and Validating transportation data from other sources. The TSDC's two levels of access make composite data available with simple online registration, and allow researchers to use detailed spatial data after completing a straight forward application process.

  11. Phonon-Assisted Ultrafast Charge Separation in a Realistic PCBM Aggregate

    E-Print Network [OSTI]

    Samuel L. Smith; Alex W. Chin

    2014-06-25

    Organic solar cells must separate strongly bound electron-hole pairs into free charges. This is achieved at interfaces between electron donor and acceptor organic semiconductors. The most popular electron acceptor is the fullerene derivative PCBM. Electron-hole separation has been observed on femtosecond timescales, which is incompatible with conventional Marcus theories of organic transport. In this work we show that ultrafast charge transport in PCBM arises from its broad range of electronic eigenstates, provided by the presence of three closely spaced delocalised bands near the LUMO level. Vibrational fluctuations enable rapid transitions between these bands, which drives an electron transport of $\\sim$3 nm within 100 fs. All this is demonstrated within a realistic tight binding Hamiltonian containing transfer integrals no larger than 8 meV.

  12. Predicting the Occurrence of Cosmetic Defects in Automotive Skin Panels

    SciTech Connect (OSTI)

    Hazra, S.; Williams, D.; Roy, R.; Aylmore, R.; Allen, M.; Hollingdale, D.

    2011-05-04

    The appearance of defects such as 'hollows' and 'shock lines' can affect the perceived quality and attractiveness of automotive skin panels. These defects are the result of the stamping process and appear as small, localized deviations from the intended styling of the panels. Despite their size, they become visually apparent after the application of paint and the perceived quality of a panel may become unacceptable. Considerable time is then dedicated to minimizing their occurrence through tool modifications. This paper will investigate the use of the wavelet transform as a tool to analyze physically measured panels. The transform has two key aspects. The first is its ability to distinguish small scale local defects from large scale styling curvature. The second is its ability to characterize the shape of a defect in terms of its wavelength and a 'correlation value'. The two features of the transform enable it to be used as a tool for locating and predicting the severity of defects. The paper will describe the transform and illustrate its application on test cases.

  13. Developmental defects in zebrafish for classification of EGF pathway inhibitors

    SciTech Connect (OSTI)

    Pruvot, Benoist; Cur, Yoann; Djiotsa, Joachim; Voncken, Audrey; Muller, Marc

    2014-01-15

    One of the major challenges when testing drug candidates targeted at a specific pathway in whole animals is the discrimination between specific effects and unwanted, off-target effects. Here we used the zebrafish to define several developmental defects caused by impairment of Egf signaling, a major pathway of interest in tumor biology. We inactivated Egf signaling by genetically blocking Egf expression or using specific inhibitors of the Egf receptor function. We show that the combined occurrence of defects in cartilage formation, disturbance of blood flow in the trunk and a decrease of myelin basic protein expression represent good indicators for impairment of Egf signaling. Finally, we present a classification of known tyrosine kinase inhibitors according to their specificity for the Egf pathway. In conclusion, we show that developmental indicators can help to discriminate between specific effects on the target pathway from off-target effects in molecularly targeted drug screening experiments in whole animal systems. - Highlights: We analyze the functions of Egf signaling on zebrafish development. Genetic blocking of Egf expression causes cartilage, myelin and circulatory defects. Chemical inhibition of Egf receptor function causes similar defects. Developmental defects can reveal the specificity of Egf pathway inhibitors.

  14. AVTA: ChargePoint America Recovery Act Charging Infrastructure Reports

    Broader source: Energy.gov [DOE]

    The Vehicle Technologies Office's Advanced Vehicle Testing Activity carries out testing on a wide range of advanced vehicles and technologies on dynamometers, closed test tracks, and on-the-road. These results provide benchmark data that researchers can use to develop technology models and guide future research and development. The American Recovery and Reinvestment Act supported a number of projects that together made up the largest ever deployment of plug-in electric vehicles and charging infrastructure in the U.S. The following reports describe results of data collected through the Chargepoint America project, which deployed 4,600 public and home charging stations throughout the U.S. This research was conducted by Idaho National Laboratory.

  15. Recovery Act Transportation Electrification

    SciTech Connect (OSTI)

    Gogineni, Kumar

    2013-12-31

    ChargePoint America demonstrated the viability, economic and environmental benefits of an electric vehicle-charging infrastructure. Electric vehicles (EVs) and plug-in electric vehicles (PHEVs) arrived in late 2010, there was a substantial lack of infrastructure to support these vehicles. ChargePoint America deployed charging infrastructure in ten (10) metropolitan regions in coordination with vehicle deliveries targeting those same regions by our OEM partners: General Motors, Nissan, Fisker Automotive, Ford, smart USA, and BMW. The metropolitan regions include Central Texas (Austin/San Antonio), Bellevue/Redmond (WA), Southern Michigan, Los Angeles area (CA), New York Metro (NY), Central Florida (Orlando/Tampa), Sacramento (CA), San Francisco/San Jose (CA), Washington DC and Boston (MA). ChargePoint America installed more than 4,600 Level 2 (220v) SAE J1772 UL listed networked charging ports in home, public and commercial locations to support approximately 2000 program vehicles. ChargePoint collected data to analyze how individuals, businesses and local governments used their vehicles. Understanding driver charging behavior patterns will provide the DoE with critical information as EV adoption increases in the United States.

  16. Spectroscopy of Charge Carriers and Traps in Field-Doped Organic Semiconductors

    SciTech Connect (OSTI)

    Zhu, Xiaoyang; Frisbie, C Daniel

    2012-08-13

    This research project aims to achieve quantitative and molecular level understanding of charge carriers and traps in field-doped organic semiconductors via in situ optical absorption spectroscopy, in conjunction with time-resolved electrical measurements. During the funding period, we have made major progress in three general areas: (1) probed charge injection at the interface between a polymeric semiconductor and a polymer electrolyte dielectric and developed a thermodynamic model to quantitatively describe the transition from electrostatic to electrochemical doping; (2) developed vibrational Stark effect to probe electric field at buried organic semiconductor interfaces; (3) used displacement current measurement (DCM) to study charge transport at organic/dielectric interfaces and charge injection at metal/organic interfaces.

  17. Ultrasonic imaging system for in-process fabric defect detection

    DOE Patents [OSTI]

    Sheen, Shuh-Haw (Naperville, IL); Chien, Hual-Te (Naperville, IL); Lawrence, William P. (Downers Grove, IL); Raptis, Apostolos C. (Downers Grove, IL)

    1997-01-01

    An ultrasonic method and system are provided for monitoring a fabric to identify a defect. A plurality of ultrasonic transmitters generate ultrasonic waves relative to the fabric. An ultrasonic receiver means responsive to the generated ultrasonic waves from the transmitters receives ultrasonic waves coupled through the fabric and generates a signal. An integrated peak value of the generated signal is applied to a digital signal processor and is digitized. The digitized signal is processed to identify a defect in the fabric. The digitized signal processing includes a median value filtering step to filter out high frequency noise. Then a mean value and standard deviation of the median value filtered signal is calculated. The calculated mean value and standard deviation are compared with predetermined threshold values to identify a defect in the fabric.

  18. UNIVERSALITY OF PHASE TRANSITION DYNAMICS: TOPOLOGICAL DEFECTS FROM SYMMETRY BREAKING

    SciTech Connect (OSTI)

    Zurek, Wojciech H.; Del Campo, Adolfo

    2014-02-13

    In the course of a non-equilibrium continuous phase transition, the dynamics ceases to be adiabatic in the vicinity of the critical point as a result of the critical slowing down (the divergence of the relaxation time in the neighborhood of the critical point). This enforces a local choice of the broken symmetry and can lead to the formation of topological defects. The Kibble-Zurek mechanism (KZM) was developed to describe the associated nonequilibrium dynamics and to estimate the density of defects as a function of the quench rate through the transition. During recent years, several new experiments investigating formation of defects in phase transitions induced by a quench both in classical and quantum mechanical systems were carried out. At the same time, some established results were called into question. We review and analyze the Kibble-Zurek mechanism focusing in particular on this surge of activity, and suggest possible directions for further progress.

  19. FADEC: Fast Authentication for Dynamic Electric Vehicle Charging

    E-Print Network [OSTI]

    Nahrstedt, Klara

    charging [1], [2] is a promising technol- ogy for charging electric vehicles (EV) while driving. The basic idea is to place charging coils under the charging pads on the road and attach charging coils to the EV the road and the coils in the EV can charge the EV battery. Dynamic charging is only possible with proper

  20. Methods for reduction of charging emissions

    SciTech Connect (OSTI)

    Schuecker, F.J.; Schulte, H. [Krupp Uhde GmbH, Dortmund (Germany)

    1997-12-31

    One of the most critical subjects in coking plants are charging emissions. The paper reviews the systems that have been used over the years to reduce charging emissions. The advantages and disadvantages are summarized for the following systems: Double collecting main with aspiration on both oven sides; Single collecting main with/without aspiration via standpipe, and extraction and cleaning of charging gas on charging car; Single collecting main with aspiration via standpipe and pretreatment of charging gas on the charging car as well as additional stationary exhaust and cleaning of charging gas; Single collecting main with aspiration via single standpipe; and Single collecting main with simultaneous aspiration via two standpipes and a U-tube connecting the oven chamber with the neighboring oven. The paper then briefly discusses prerequisites for reduction of charging emissions.