Sample records for defects charge transport

  1. Charged Local Defects in Extended Systems

    SciTech Connect (OSTI)

    Schultz, Peter A.

    1999-05-25T23:59:59.000Z

    The conventional approach to treating charged defects in extended systems in first principles calculations is via the supercell approximation using a neutralizing jellium background charge. I explicitly demonstrate shortcomings of this standard approach and discuss the consequences. Errors in the electrostatic potential surface over the volume of a supercell are shown to be comparable to a band gap energy in semiconductor materials, for cell sizes typically used in first principles simulations. I present an alternate method for eliminating the divergence of the Coulomb potential in supercell calculations of charged defects in extended systems that embodies a correct treatment of the electrostatic potential in the local viciniq of the a charged defect, via a mixed boundary condition approach. I present results of first principles calculations of charged vacancies in NaCl that illustrate the importance of polarization effects once an accurate representation of the local potential is obtained. These polarization effects, poorly captured in small supercells, also impact the energetic on the scale of typical band gap energies.

  2. Transport of elliptic intense charged -particle beams

    E-Print Network [OSTI]

    Zhou, J. (Jing), 1978-

    2006-01-01T23:59:59.000Z

    The transport theory of high-intensity elliptic charged-particle beams is presented. In particular, the halo formation and beam loss problem associated with the high space charge and small-aperture structure is addressed, ...

  3. Light defection due to a charged, rotating body

    E-Print Network [OSTI]

    Sarani Chakraborty; A. K. Sen

    2014-06-05T23:59:59.000Z

    According to GTR and subsequent developments in the field, it is known that there are three factors namely mass, rotation and charge that can influence the space-time geometry. Accordingly, we discuss the effect of space-time geometry of a charged, rotating body on the motion of the light ray. We obtained the expression for equatorial defection of light due to such a body up to fourth order term. In our expression for defection angle it is clear that charge can influence the path of light ray. We used the null geodesic approach of light ray for our calculation. If we set the charge to zero our expression of bending angle gets reduced to the Kerr equatorial bending angle.If we set rotation to zero our expression reduces to Resinner-Nordstr$\\ddot{o}$m defection angle and if we set both charge and rotation to zero our expression reduces to Schwarzschild bending angle. However, we get non-zero bending angle for a hypothetical massless, rotating, charged body.

  4. Defects activated photoluminescence in two-dimensional semiconductors: interplay between bound, charged, and free excitons

    E-Print Network [OSTI]

    Tongay, Sefaattin

    Point defects in semiconductors can trap free charge carriers and localize excitons. The interaction between these defects and charge carriers becomes stronger at reduced dimensionalities, and is expected to greatly influence ...

  5. Oxygen sublattice defect in cobalt oxide : formation, migration, charge localization and thermodynamic processes

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    643 Oxygen sublattice defect in cobalt oxide : formation, migration, charge localization of oxygen defects in CoO using classical simulations. The charge localization in the oxygen vacancy has]. The defect concentration in the oxygen sublattice is several orders of magnitude smaller, but never- theless

  6. Transport in Charged Colloids Driven by Thermoelectricity

    E-Print Network [OSTI]

    Alois Würger

    2014-01-29T23:59:59.000Z

    We study the thermal diffusion coefficient DT of a charged colloid in a temperature gradient, and find that it is to a large extent determined by the thermoelectric response of the electrolyte solution. The thermally induced salinity gradient leads in general to a strong increase with temperature. The difference of the heat of transport of coions and counterions gives rise to a thermoelectric field that drives the colloid to the cold or to the warm, depending on the sign of its charge. Our results provide an explanation for recent experimental findings on thermophoresis in colloidal suspensions.

  7. Nanoscale Charge Transport in Excitonic Solar Cells

    SciTech Connect (OSTI)

    Venkat Bommisetty, South Dakota State University

    2011-06-23T23:59:59.000Z

    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.

  8. Defect-Enhanced Charge Transfer by Ion-Solid Interactions in...

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

    transfer effects on recoil atoms. Citation: Gao F, HY Xiao, XT Zu, M Posselt, and WJ Weber.2009."Defect-Enhanced Charge Transfer by Ion-Solid Interactions in SiC using...

  9. Scattering of charge carriers in graphene induced by topological defects

    E-Print Network [OSTI]

    J. M. Fonseca; W. A. Moura-Melo; A. R. Pereira

    2011-08-04T23:59:59.000Z

    We study the scattering of graphene quasiparticles by topological defects, represented by holes, pentagons and heptagons. For holes, we found that at low concentration they give a negligible contribution to the resistivity. Whenever pentagons or heptagons are introduced we realize that a fermionic current is scattered by defects.

  10. Graphene Produces More Efficient Charge Transport Inside an Organic

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

    Graphene Produces More Efficient Charge Transport Inside an Organic Semiconductor Graphene, a two dimensional semi-metal made of sp 2 hybridized carbon, is an outstanding material...

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

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

    Graphene Produces More Efficient Charge Transport Inside an Organic Semiconductor Friday, January 30, 2015 Graphene, a two dimensional semi-metal made of sp2 hybridized carbon, is...

  12. 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...

  13. Aspects of charge recombination and charge transport in organic solar cells and light-emitting devices

    E-Print Network [OSTI]

    Difley, Seth

    2010-01-01T23:59:59.000Z

    In this thesis, aspects of charge reconbination and charge transport in organic solar cells and light-emitting devices are presented. These devices show promise relative to traditional inorganic semiconductors. We show ...

  14. Infrared Charge-Modulation Spectroscopy of Defects in Phosphorus Doped Amorphous Silicon

    E-Print Network [OSTI]

    Schiff, Eric A.

    Infrared Charge-Modulation Spectroscopy of Defects in Phosphorus Doped Amorphous Silicon KAI ZHU Solar, Toano, VA 23168 USA ABSTRACT We present infrared charge-modulation absorption spectra have been developing an infrared modulation spectroscopy technique that probes the optical spectra

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

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

    Surface-Plasmon Assisted Exciton and Charge Carrier Transport in One Dimensional Nanostructures February 21, 2013 at 3pm36-428 Andrei Piryatinski Physics of Condensed Matter and...

  16. CHARACTERIZING COUPLED CHARGE TRANSPORT WITH MULTISCALE MOLECULAR DYNAMICS

    SciTech Connect (OSTI)

    Swanson, Jessica

    2011-08-31T23:59:59.000Z

    This is the final progress report for Award DE-SC0004920, entitled 'Characterizing coupled charge transport with multi scale molecular dynamics'. The technical abstract will be provided in the uploaded report.

  17. Effect of topological defects and Coulomb charge on the low energy quantum dynamics of gapped graphene

    E-Print Network [OSTI]

    Baishali Chakraborty; Kumar S. Gupta; Siddhartha Sen

    2012-08-03T23:59:59.000Z

    We study the combined effect of a conical topological defect and a Coulomb charge impurity on the dynamics of Dirac fermions in gapped graphene. Beyond a certain strength of the Coulomb charge, quantum instability sets in, which demarcates the boundary between sub and supercritical values of the charge. In the subcritical regime, for certain values of the system parameters, the allowed boundary conditions in gapped graphene cone can be classified in terms of a single real parameter. We show that the observables such as local density of states, scattering phase shifts and the bound state spectra are sensitive to the value of this real parameter, which is interesting from an empirical point of view. For a supercritical Coulomb charge, we analyze the system with a regularized potential as well as with a zigzag boundary condition and find the effect of the sample topology on the observable features of the system.

  18. Transport in charged colloids driven by thermoelectricity Alois Wrger

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    . There is no complete description for the underlying physical forces, and even the sign of the thermophoretic mobility negative thermophoretic mobility has been reported for charged latex spheres in a bu¤ered so- lution. Like any linear transport coe¢ cient in a viscous uid, the thermophoretic mobility DT has

  19. Surface-Charge-Governed Ion Transport in Nanofluidic Channels Derek Stein, Maarten Kruithof, and Cees Dekker

    E-Print Network [OSTI]

    Dekker, Cees

    Surface-Charge-Governed Ion Transport in Nanofluidic Channels Derek Stein, Maarten Kruithof the role of surface charge in governing conductance at low salt concentrations. Nanofluidic channels [Fig

  20. Ratchet transport for a chain of interacting charged particles

    E-Print Network [OSTI]

    S. I. Denisov; E. S. Denisova; P. Hänggi

    2006-03-15T23:59:59.000Z

    We study analytically and numerically the overdamped, deterministic dynamics of a chain of {\\it charged}, interacting particles driven by a longitudinal alternating electric field and additionally interacting with a smooth ratchet potential. We derive the equations of motion, analyze the general properties of their solutions and find the drift criterion for chain motion. For ratchet potentials of the form of a double-sine and a phase-modulated sine it is demonstrated that both, a so-called integer and fractional transport of the chain can occur. Explicit results for the directed chain transport for these two classes of ratchet potentials are presented.

  1. Charge transport properties of CdMnTe radiation detectors

    SciTech Connect (OSTI)

    Kim K.; Rafiel, R.; Boardman, M.; Reinhard, I.; Sarbutt, A.; Watt, G.; Watt, C.; Uxa, S.; Prokopovich, D.A.; Belas, E.; Bolotnikov, A.E.; James, R.B.

    2012-04-11T23:59:59.000Z

    Growth, fabrication and characterization of indium-doped cadmium manganese telluride (CdMnTe)radiation detectors have been described. Alpha-particle spectroscopy measurements and time resolved current transient measurements have yielded an average charge collection efficiency approaching 100 %. Spatially resolved charge collection efficiency maps have been produced for a range of detector bias voltages. Inhomogeneities in the charge transport of the CdMnTe crystals have been associated with chains of tellurium inclusions within the detector bulk. Further, it has been shown that the role of tellurium inclusions in degrading chargecollection is reduced with increasing values of bias voltage. The electron transit time was determined from time of flight measurements. From the dependence of drift velocity on applied electric field the electron mobility was found to be n = (718 55) cm2/Vs at room temperature.

  2. Vehicle remote charge-all electric transportation system

    SciTech Connect (OSTI)

    Parise, R.J.

    1998-07-01T23:59:59.000Z

    The development of a pollution-free transportation system that utilizes technology from the defense industry combines two industries in a commercial venture. In conjunction with the abatement of pollution that an all-electric transportation system would realize, the defense industry is looking for a commercial market for the technology that it has developed over the years. This new transportation system will accomplish both these goals. To date, the most reliable electric source has been overhead tethered lines or on-ground tracks in public transportation. But these greatly reduce the convenience of route changes and are at the mercy of small traffic pattern changes which can cause traffic tie-ups. The ideal electric bus would have a completely mobile energy source, such as a battery pack. But the limited range of a battery powered vehicle has diminished its use to only specific cases. In private vehicles also, the limited range of zero-pollution battery power has reduced the desirability of all-electric transportation. The electric transportation system proposed here will eliminate these problems. Buses will be sent out on their routes with convenient in-route charging. There will be minimum route changes to accommodate vehicle recharging. The buses will have full mobility and can avoid any traffic tie-ups. The charging of these on-board electrical energy storage systems will take place via a wireless power transmission network that will be established along the roadside on existing power line (telephone) poles or new stand-alone poles that would be in conjunction with the existing poles. Radio frequency (RF) wavelengths such as a microwave or a millimeterwave system or optical frequencies (OF), a laser based system, are wireless energy transmission systems. Utilizing this means to establish a nationwide transportation system will take a technology that has been defense based and use it in a commercial application.

  3. 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

  4. Charge Transport and Glassy Dynamics in Ionic Liquids

    SciTech Connect (OSTI)

    Sangoro, Joshua R [ORNL; Kremer, Friedrich [University of Leipzig

    2012-01-01T23:59:59.000Z

    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.

  5. 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, Søren; Nørgaard, Kasper; Hassenkam, Tue; Laursen, Bo W. [Nano-Science Center and Department of Chemistry, University of Copenhagen, Universitetparken 5, 2100 Københaven Ø (Denmark)

    2014-09-01T23:59:59.000Z

    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.

  6. Charge transport in micas: The kinetics of FeII/III electron...

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

    transport in micas: The kinetics of FeIIIII electron transfer in the octahedral sheet. Charge transport in micas: The kinetics of FeIIIII electron transfer in the octahedral...

  7. International Journal of Mass Spectrometry 219 (2002) 7377 Protein charge transport in gas phase

    E-Print Network [OSTI]

    Sheu, Sheh-Yi

    temperature limit, the rotational energy can be transferred with very high efficiency and hence one obtainsInternational Journal of Mass Spectrometry 219 (2002) 73­77 Protein charge transport in gas phase high charge transport efficiency. (Int J Mass Spectrom 219 (2002) 73­77) © 2002 Elsevier Science B

  8. Coulomb screening in graphene with topological defects

    E-Print Network [OSTI]

    Baishali Chakraborty; Kumar S. Gupta; Siddhartha Sen

    2015-02-20T23:59:59.000Z

    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.

  9. Temporal and Dose Kinetics of Tunnel Relaxation of Non-Equilibrium Near-Interfacial Charged Defects in Insulators

    E-Print Network [OSTI]

    Zebrev, Gennady I

    2015-01-01T23:59:59.000Z

    This paper is devoted mainly to mathematical aspects of modeling and simulation of tunnel relaxation of nonequilibrium charged oxide traps located at/near the interface insulator - conductive channel, for instance in irradiated MOS devices. The generic form of the tunnel annealing response function was derived from the rate equation for the charged defect buildup and annealing as a linear superposition of the responses of different defects with different time constants. Using this linear response function, a number of important practical problems are analyzed and discussed. Combined tunnel and thermal or RICN annealing, power-like temporal relaxation after a single ion strike into the gate oxide, are described in context of general approach.

  10. 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 Brasília, 70919-970, Brasília-DF (Brazil); Qu, Fanyao [Institute of Physics, University of Brasília, 70919-970, Brasília-DF (Brazil); Department of Physics, The University of Texas at Austin, Austin, Texas 78712 (United States)

    2014-09-21T23:59:59.000Z

    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.

  11. The role of space charge compensation for ion beam extraction and ion beam transport (invited)

    SciTech Connect (OSTI)

    Spädtke, Peter, E-mail: p.spaedtke@gsi.de [GSI Helmholtzzentrum für Schwerionenforschung GmbH (Germany)] [GSI Helmholtzzentrum für Schwerionenforschung GmbH (Germany)

    2014-02-15T23:59:59.000Z

    Depending on the specific type of ion source, the ion beam is extracted either from an electrode surface or from a plasma. There is always an interface between the (almost) space charge compensated ion source plasma, and the extraction region in which the full space charge is influencing the ion beam itself. After extraction, the ion beam is to be transported towards an accelerating structure in most cases. For lower intensities, this transport can be done without space charge compensation. However, if space charge is not negligible, the positive charge of the ion beam will attract electrons, which will compensate the space charge, at least partially. The final degree of Space Charge Compensation (SCC) will depend on different properties, like the ratio of generation rate of secondary particles and their loss rate, or the fact whether the ion beam is pulsed or continuous. In sections of the beam line, where the ion beam is drifting, a pure electrostatic plasma will develop, whereas in magnetic elements, these space charge compensating electrons become magnetized. The transport section will provide a series of different plasma conditions with different properties. Different measurement tools to investigate the degree of space charge compensation will be described, as well as computational methods for the simulation of ion beams with partial space charge compensation.

  12. 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

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

    E-Print Network [OSTI]

    Gian Michele Graf; Gregorio Ortelli

    2007-09-19T23:59:59.000Z

    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.

  14. Parametrization of extended Gaussian disorder models from microscopic charge transport

    E-Print Network [OSTI]

    Schmidt, Volker

    -size effects at small charge densities, the data is fitted to the uncorrelated and correlated extended Gaussian to compound synthesis. 1 Introduction The optimization of organic photovoltaic cells,1,2 light emitting diodes,3 and field effect tran- sistors4 requires the improvement of the charge-carrier mobility, µ

  15. Defect chemistry and transport properties of BaxCe0.85M0.15O3-

    E-Print Network [OSTI]

    by the generation of positively charged defects, typically oxygen vacancies. Oxygen-vacancy content, in turn at vacant oxygen sites. We propose here, on the basis of x-ray powder diffraction studies, electron and derivatives) by both oxygen ions and/ or electrons has been widely studied and such materials find

  16. 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

    2010-09-01T23:59:59.000Z

    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.

  17. Charge Transport through Organized Organic Assemblies in Confined Geometries 

    E-Print Network [OSTI]

    Schuckman, Amanda Eileen

    2012-07-16T23:59:59.000Z

    is the calculated non-space charge limited conductance. This photogated device is an early example of an all- organic molecular electronic. Reproduced from ref. [45] with permission of the copyright holders... for the progression of smaller and faster devices being able to replicate the invaluable techniques to scale down the feature size with little or no modification to their methods. ____________ This dissertation follows the style of the Journal...

  18. Charge Transport through Organized Organic Assemblies in Confined Geometries

    E-Print Network [OSTI]

    Schuckman, Amanda Eileen

    2012-07-16T23:59:59.000Z

    of Advisory Committee: Dr. James D. Batteas Organic molecules such as porphyrins and alkanethiols are currently being investigated for applications such as sensors, light-emitting diodes and single electron transistors. Porphyrins are stable, highly..., molecules have shown their potential for applications such as information storage, charge separation, single electron transistors, current routers and gates and continue to be designed for use in solar cells, organic light-emitting diodes, sensors...

  19. Space Charge Compensation in the Linac4 Low Energy Beam Transport Line with Negative Hydrogen Ions

    E-Print Network [OSTI]

    Valerio-Lizarraga, C; Leon-Monzon, I; Lettry, J; Midttun, O; Scrivens, R

    2013-01-01T23:59:59.000Z

    The space charge effect of low energy, unbunched ion beams can be compensated by the trapping of ions or electrons into the beam potential. This has been studied for the 45 keV negative hydrogen ion beam in the CERN Linac4 Low Energy Beam Tranport (LEBT) using the package IBSimu1, which allows the space charge calculation of the particle trajectories. The results of the beam simulations will be compared to emittance measurements of an H- beam at the CERN Linac4 3 MeV test stand, where the injection of hydrogen gas directly into the beam transport region has been used to modify the space charge compensation degree.

  20. Studies on relative effects of charged and neutral defects in hydrogenated amorphous silicon. Final report, 1 October 1989--31 December 1990

    SciTech Connect (OSTI)

    Silver, M. [North Carolina Univ., Chapel Hill, NC (United States)

    1992-02-01T23:59:59.000Z

    This report covers the third year of a continuing research study to understand the relative importance of charged and neutral defects in amorphous silicon. The objective of the study is to explore the electronic structure, including neutral and charged defects, an optoelectronic effects including the formation of Staebler-Wronski defects. The study concentrated on exploring electroluminescence experimentally and interpreting the results employing a simple guiding model. The simple guiding model assumes an exponential density of states and recombination rate constants (radiative and non-radiative) which are governed by hopping transitions. Measurements were also made as a function of photodegradation of the material. The results implicate that the radiative recombination processes are not distant pair tunneling but rather results from electrons hopping down due to the coulomb interactions. Preliminary experiments have been made on the effect of photodegradation on transient space charge limited currents in n/i/n structures. These experiments can directly yield information on the occupied defects centers induced by the photodegradation and are not a result of recombination processes. To date the results seems to be consistent with a picture which places the doubly occupied defects at quite a high energy ({approx_equal} 0.4 e.v. below the conduction band).

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

    E-Print Network [OSTI]

    Andrey N. Aleshin

    2007-01-31T23:59:59.000Z

    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.

  2. Charge transport in mixed CdSe and CdTe colloidal nanocrystal films

    E-Print Network [OSTI]

    Bawendi, Moungi G.

    We report the influence of trap states on charge transport through films of mixed CdTe and CdSe nanocrystals (NCs) between lateral electrodes, through layered films of CdTe and CdSe NCs in a layered geometry, and through ...

  3. Space charge compensation in the Linac4 low energy beam transport line with negative hydrogen ions

    SciTech Connect (OSTI)

    Valerio-Lizarraga, Cristhian A., E-mail: cristhian.alfonso.valerio.lizarraga@cern.ch [CERN, Geneva (Switzerland); Departamento de Investigación en Física, Universidad de Sonora, Hermosillo (Mexico); Lallement, Jean-Baptiste; Lettry, Jacques; Scrivens, Richard [CERN, Geneva (Switzerland)] [CERN, Geneva (Switzerland); Leon-Monzon, Ildefonso [Facultad de Ciencias Fisico-Matematicas, Universidad Autónoma de Sinaloa, Culiacan (Mexico)] [Facultad de Ciencias Fisico-Matematicas, Universidad Autónoma de Sinaloa, Culiacan (Mexico); Midttun, Øystein [CERN, Geneva (Switzerland) [CERN, Geneva (Switzerland); University of Oslo, Oslo (Norway)

    2014-02-15T23:59:59.000Z

    The space charge effect of low energy, unbunched ion beams can be compensated by the trapping of ions or electrons into the beam potential. This has been studied for the 45 keV negative hydrogen ion beam in the CERN Linac4 Low Energy Beam Transport using the package IBSimu [T. Kalvas et al., Rev. Sci. Instrum. 81, 02B703 (2010)], which allows the space charge calculation of the particle trajectories. The results of the beam simulations will be compared to emittance measurements of an H{sup ?} beam at the CERN Linac4 3 MeV test stand, where the injection of hydrogen gas directly into the beam transport region has been used to modify the space charge compensation degree.

  4. Charge Transport Limitations in Self-Assembled TiO2 Photoanodes for Dye-Sensitized Solar Cells

    E-Print Network [OSTI]

    Steiner, Ullrich

    Charge Transport Limitations in Self-Assembled TiO2 Photoanodes for Dye-Sensitized Solar Cells and Storage; Energy and Charge Transport The dye-sensitized solar cell (DSC) has attracted wide- spread. Thomson Avenue, Cambridge, CB3 0HE, United Kingdom *S Supporting Information ABSTRACT: Solid-state dye-sensitized

  5. Charge Transport Properties in TiO2 Network with Different Particle Sizes for Dye Sensitized Solar Cells

    E-Print Network [OSTI]

    Cao, Guozhong

    the large improvement in performance of dye sensitized solar cells (DSCs) achieved in 1991, mesoporousCharge Transport Properties in TiO2 Network with Different Particle Sizes for Dye Sensitized Solar sensitized solar cells, nanoparticle size, impedance, charge transport properties INTRODUCTION Since

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

    E-Print Network [OSTI]

    McCreary, Kathleen M.

    2012-01-01T23:59:59.000Z

    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……………………………………………………………..

  7. 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.

    2013-01-10T23:59:59.000Z

    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.

  8. PATH: a lumped-element beam-transport simulation program with space charge

    SciTech Connect (OSTI)

    Farrell, J.A.

    1983-01-01T23:59:59.000Z

    PATH is a group of computer programs for simulating charged-particle beam-transport systems. It was developed for evaluating the effects of some aberrations without a time-consuming integration of trajectories through the system. The beam-transport portion of PATH is derived from the well-known program, DECAY TURTLE. PATH contains all features available in DECAY TURTLE (including the input format) plus additional features such as a more flexible random-ray generator, longitudinal phase space, some additional beamline elements, and space-charge routines. One of the programs also provides a simulation of an Alvarez linear accelerator. The programs, originally written for a CDC 7600 computer system, also are available on a VAX-VMS system. All of the programs are interactive with input prompting for ease of use.

  9. 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)

    2014-01-07T23:59:59.000Z

    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.

  10. Effect of conformations on charge transport in a thin elastic tube

    E-Print Network [OSTI]

    Balakrishnan, Radha

    2008-01-01T23:59:59.000Z

    We study the effect of conformations on charge transport in a thin elastic tube. Using the Kirchhoff model for a tube with any given Poisson ratio, cross-sectional shape and intrinsic twist, we obtain a class of exact solutions for its conformation. The tube's torsion is found in terms of its intrinsic twist and its Poisson ratio, while its curvature satisfies a nonlinear differential equation which supports exact {\\it periodic} solutions in the form of Jacobi elliptic functions, which we call {\\it conformon lattice} solutions. These solutions typically describe conformations with loops. Each solution induces a corresponding quantum effective {\\it periodic} potential in the Schr\\"{o}dinger equation for an electron in the tube. The wave function describes the delocalization of the electron along the central axis of the tube. We discuss some possible applications of this novel mechanism of charge transport.

  11. Effect of conformations on charge transport in a thin elastic tube

    E-Print Network [OSTI]

    Radha Balakrishnan; Rossen Dandoloff

    2008-03-24T23:59:59.000Z

    We study the effect of conformations on charge transport in a thin elastic tube. Using the Kirchhoff model for a tube with any given Poisson ratio, cross-sectional shape and intrinsic twist, we obtain a class of exact solutions for its conformation. The tube's torsion is found in terms of its intrinsic twist and its Poisson ratio, while its curvature satisfies a nonlinear differential equation which supports exact {\\it periodic} solutions in the form of Jacobi elliptic functions, which we call {\\it conformon lattice} solutions. These solutions typically describe conformations with loops. Each solution induces a corresponding quantum effective {\\it periodic} potential in the Schr\\"{o}dinger equation for an electron in the tube. The wave function describes the delocalization of the electron along the central axis of the tube. We discuss some possible applications of this novel mechanism of charge transport.

  12. Coulomb screening in graphene with topological defects

    E-Print Network [OSTI]

    Chakraborty, Baishali; Sen, Siddhartha

    2015-01-01T23:59:59.000Z

    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 imp...

  13. Quasi-Ohmic Single Molecule Charge Transport through Highly Conjugated meso-to-meso Ethyne-Bridged Porphyrin Wires

    E-Print Network [OSTI]

    Borguet, Eric

    ),24-29 including oligophenyleneimines (OPIs),7 butadiyne-bridged multi(porphyrin) systems,15(tetrathiafulvalene-pyromellitic- diimide-imine)s.27 Frisbie et al. have chronicled a change in charge transport mechanism in OPIs from

  14. Homogenization of the Poisson-Nernst-Planck Equations for Ion Transport in Charged Porous Media

    E-Print Network [OSTI]

    Markus Schmuck; Martin Z. Bazant

    2014-07-14T23:59:59.000Z

    Effective Poisson-Nernst-Planck (PNP) equations are derived for macroscopic ion transport in charged porous media under periodic fluid flow by an asymptotic multi-scale expansion with drift. The microscopic setting is a two-component periodic composite consisting of a dilute electrolyte continuum (described by standard PNP equations) and a continuous dielectric matrix, which is impermeable to the ions and carries a given surface charge. Four new features arise in the upscaled equations: (i) the effective ionic diffusivities and mobilities become tensors, related to the microstructure; (ii) the effective permittivity is also a tensor, depending on the electrolyte/matrix permittivity ratio and the ratio of the Debye screening length to the macroscopic length of the porous medium; (iii) the microscopic fluidic convection is replaced by a diffusion-dispersion correction in the effective diffusion tensor; and (iv) the surface charge per volume appears as a continuous "background charge density", as in classical membrane models. The coefficient tensors in the upscaled PNP equations can be calculated from periodic reference cell problems. For an insulating solid matrix, all gradients are corrected by the same tensor, and the Einstein relation holds at the macroscopic scale, which is not generally the case for a polarizable matrix, unless the permittivity and electric field are suitably defined. In the limit of thin double layers, Poisson's equation is replaced by macroscopic electroneutrality (balancing ionic and surface charges). The general form of the macroscopic PNP equations may also hold for concentrated solution theories, based on the local-density and mean-field approximations. These results have broad applicability to ion transport in porous electrodes, separators, membranes, ion-exchange resins, soils, porous rocks, and biological tissues.

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

    SciTech Connect (OSTI)

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

    1982-01-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Jiang, Yin; Liao, Jinfeng

    2015-01-01T23:59:59.000Z

    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.

  17. Mode-selective vibrational control of charge transport in $?$-conjugated molecular materials

    E-Print Network [OSTI]

    Artem A. Bakulin; Robert Lovrin?i?; Yu Xi; Oleg Selig; Huib J. Bakker; Yves L. A. Rezus; Pabitra K. Nayak; Alexandr Fonari; Veaceslav Coropceanu; Jean-Luc Brédas; David Cahen

    2015-03-02T23:59:59.000Z

    The soft character of organic materials leads to strong coupling between molecular nuclear and electronic dynamics. This coupling opens the way to control charge transport in organic electronic devices by inducing molecular vibrational motions. However, despite encouraging theoretical predictions, experimental realization of such control has remained elusive. Here we demonstrate experimentally that photoconductivity in a model organic optoelectronic device can be controlled by the selective excitation of molecular vibrations. Using an ultrafast infrared laser source to create a coherent superposition of vibrational motions in a pentacene/C60 photoresistor, we observe that excitation of certain modes in the 1500-1700 cm$^{-1}$ region leads to photocurrent enhancement. Excited vibrations affect predominantly trapped carriers. The effect depends on the nature of the vibration and its mode-specific character can be well described by the vibrational modulation of intermolecular electronic couplings. Vibrational control thus presents a new tool for studying electron-phonon coupling and charge dynamics in (bio)molecular materials.

  18. Gate dielectric degradation: Pre-existing vs. generated defects

    SciTech Connect (OSTI)

    Veksler, Dmitry, E-mail: Dmitry.Veksler@sematech.org, E-mail: gennadi.bersuker@sematech.org; Bersuker, Gennadi, E-mail: Dmitry.Veksler@sematech.org, E-mail: gennadi.bersuker@sematech.org [SEMATECH Inc., 257 Fuller Rd., Albany, New York 12203 (United States)

    2014-01-21T23:59:59.000Z

    We consider the possibility that degradation of the electrical characteristics of high-k gate stacks under low voltage stresses of practical interest is caused primarily by activation of pre-existing defects rather than generation of new ones. In nFETs in inversion, in particular, defect activation is suggested to be associated with the capture of an injected electron: in this charged state, defects can participate in a fast exchange of charge carriers with the carrier reservoir (substrate or gate electrode) that constitutes the physical process underlying a variety of electrical measurements. The degradation caused by the activation of pre-existing defects, as opposed to that of new defect generation, is both reversible and exhibits a tendency to saturate through the duration of stress. By using the multi-phonon assisted charge transport description, it is demonstrated that the trap activation concept allows reproducing a variety of experimental results including stress time dependency of the threshold voltage, leakage current, charge pumping current, and low frequency noise. Continuous, long-term degradation described by the power law time dependency is shown to be determined by the activation of defects located in the interfacial SiO{sub 2} layer of the high-k gate stacks. The findings of this study can direct process optimization efforts towards reduction of as-grown precursors of the charge trapping defects as the major factor affecting reliability.

  19. Transport mechanisms and experimental evidence of positively charged dust particles in an argon plasma

    SciTech Connect (OSTI)

    Brown, D.A.; Hareland, W.A. [Sandia National Labs., Albuquerque, NM (United States); Collins, S.M. [Univ. of Arizona, Tucson, AZ (United States)

    1995-12-31T23:59:59.000Z

    It is well known that dense particle clouds often reside within the steady-state plasma; however, particle transport in the critical post-plasma period has not yet been fully explored. To better understand and characterize particle behavior, charge and transport properties of dust particles in an argon plasma, contained within a Gaseous Electronics Conference (GEC) reference cell, were studied in the steady-state and post-plasma regimes of a 500 mTorr, 25 W argon discharge. Using separate water chillers to control independently the temperatures of the upper and lower electrodes, various temperature gradients were imposed on the plasma and thermophoretic transport of the particle clouds observed for both steady and decaying discharges. Next, using a pulsed rf power supply and a tuned Langmuir probe, the decay times of electrons and ions were measured in the afterglow. Finally, utilizing high-speed video in concert with 10 mW He-Ne laser light, post-plasma particle trajectories were observed for various electric fields and electrode temperatures. Results were then compared to calculations from a net force model that included gravity, the electric field, fluid flow, ion drag, and thermophoresis. It was found that temperature gradients greater than {approximately} 10 C/cm significantly altered particle cloud configurations in steady plasmas, and provided a strong transport mechanism in the afterglow. Electrically, the measured ion density decay time was approximately equal to that of the electrons, consistent with ambipolar diffusion.

  20. 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

    2015-01-07T23:59:59.000Z

    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.

  1. A Generalized Boltzmann Fokker-Planck Method for Coupled Charged Particle Transport

    SciTech Connect (OSTI)

    Prinja, Anil K

    2012-01-09T23:59:59.000Z

    The goal of this project was to develop and investigate the performance of reduced-physics formulations of high energy charged particle (electrons, protons and heavier ions) transport that are computationally more efficient than not only analog Monte Carlo methods but also the established condensed history Monte Carlo technique. Charged particles interact with matter by Coulomb collisions with target nuclei and electrons, by bremsstrahlung radiation loss and by nuclear reactions such as spallation and fission. Of these, inelastic electronic collisions and elastic nuclear collisions are the dominant cause of energy-loss straggling and angular deflection or range straggling of a primary particle. These collisions are characterized by extremely short mean free paths (sub-microns) and highly peaked, near-singular differential cross sections about forward directions and zero energy loss, with the situation for protons and heavier ions more extreme than for electrons. For this reason, analog or truephysics single-event Monte Carlo simulation, while possible in principle, is computationally prohibitive for routine calculation of charged particle interaction phenomena.

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

    E-Print Network [OSTI]

    Gaw?dzki, Krzysztof

    2015-01-01T23:59:59.000Z

    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...

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

    E-Print Network [OSTI]

    Krzysztof Gaw?dzki; Clément Tauber

    2015-01-29T23:59:59.000Z

    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.

  4. Atomic Scale Details of Defect-Boundary Interactions

    E-Print Network [OSTI]

    Chen, Di

    2014-12-18T23:59:59.000Z

    consists of alternately positioned interstitials and vacancies. The subsequent defect annihilation between neighboring defects on the chain leads to the defect transport. We identify three types of defect transport models which involve different chains...

  5. Single charge sensing and transport in double quantum dots fabricated from commercially grown Si/SiGe heterostructures

    E-Print Network [OSTI]

    Payette, C; Koppinen, P J; Dovzhenko, Y; Sturm, J C; Petta, J R

    2011-01-01T23:59:59.000Z

    We perform quantum Hall measurements on three types of commercially available modulation doped Si/SiGe heterostructures to determine their suitability for depletion gate defined quantum dot devices. By adjusting the growth parameters, we are able to achieve electron gases with charge densities 1-3 X 10^{11}/cm^2 and mobilities in excess of 100,000 cm^2/Vs. Double quantum dot devices fabricated on these heterostructures show clear evidence of single charge transitions as measured in dc transport and charge sensing and exhibit electron temperatures of 100 mK in the single quantum dot regime.

  6. Single charge sensing and transport in double quantum dots fabricated from commercially grown Si/SiGe heterostructures

    E-Print Network [OSTI]

    C. Payette; K. Wang; P. J. Koppinen; Y. Dovzhenko; J. C. Sturm; J. R. Petta

    2012-03-21T23:59:59.000Z

    We perform quantum Hall measurements on three types of commercially available modulation doped Si/SiGe heterostructures to determine their suitability for depletion gate defined quantum dot devices. By adjusting the growth parameters, we are able to achieve electron gases with charge densities 1-3 X 10^{11}/cm^2 and mobilities in excess of 100,000 cm^2/Vs. Double quantum dot devices fabricated on these heterostructures show clear evidence of single charge transitions as measured in dc transport and charge sensing and exhibit electron temperatures of 100 mK in the single quantum dot regime.

  7. NEI Workshop, Nice, September 24-26, 2006Peter Peumans (ppeumans@stanford.edu) Energy and Charge Transport on the

    E-Print Network [OSTI]

    1 NEI Workshop, Nice, September 24-26, 2006Peter Peumans (ppeumans@stanford.edu) Energy and Charge Transport on the Nanoscale in Organic and Organic- Metallic Composite Solar Cells Peter Peumans Department@stanford.edu) Acknowledgements Students Shanbin Zhao Mukul Agrawal Jung-Yong Lee Postdoc Shigeo Fujimori Stanford Prof. Mark

  8. Dynamics of charge transport and recombination in ZnO nanorod array dye-sensitized solar cells

    E-Print Network [OSTI]

    Dynamics of charge transport and recombination in ZnO nanorod array dye-sensitized solar cells Alex nanoparticles. Introduction Dye-Sensitized Solar Cells (DSSCs) comprise an increasingly attractive alternative photovoltaic technology.1,2 These photo- electrochemical cells use molecular dyes to sensitize high-area, wide

  9. 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.

    1981-01-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Imran, Z.; Rafiq, M. A., E-mail: aftab@cantab.net; Hasan, M. M. [Micro and Nano Devices Group, Department of Metallurgy and Materials Engineering, Pakistan Institute of Engineering and Applied Sciences (PIEAS), P.O. Nilore, Islamabad, 45650 (Pakistan)

    2014-06-15T23:59:59.000Z

    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.

  11. Low temperature charge transport and microwave absorption of carbon coated iron nanoparticles–polymer composite films

    SciTech Connect (OSTI)

    Prasad, V., E-mail: vishnu@physics.iisc.ernet.in [Department of Physics, Indian Institute of Science, Bangalore 560 012 (India)

    2012-06-15T23:59:59.000Z

    Highlights: ? Carbon coated Fe nanoparticle–PVC composite films were prepared by solution casting method. ? A low electrical percolation threshold of 2.2 was achieved. ? The low temperature electrical conductivity follows variable range hopping type conduction. ? An EMI shielding of 18 dB was achieved in 200 micron thick film. -- Abstract: In this paper, the low temperature electrical conductivity and microwave absorption properties of carbon coated iron nanoparticles–polyvinyl chloride composite films are investigated for different filler fractions. The filler particles are prepared by the pyrolysis of ferrocene at 980 °C and embedded in polyvinyl chloride matrix. The high resolution transmission electron micrographs of the filler material have shown a 5 nm thin layer graphitic carbon covering over iron particles. The room temperature electrical conductivity of the composite film changes by 10 orders of magnitude with the increase of filler concentration. A percolation threshold of 2.2 and an electromagnetic interference shielding efficiency (EMI SE) of ?18.6 dB in 26.5–40 GHz range are observed for 50 wt% loading. The charge transport follows three dimensional variable range hopping conduction.

  12. Resonant charge-exchange involving excited helium atoms and reactive transport of local thermodynamic equilibrium helium plasma

    SciTech Connect (OSTI)

    Kosarim, A. V.; Smirnov, B. M. [Joint Institute for High Temperatures RAS, Moscow (Russian Federation); Laricchiuta, A. [CNR IMIP Bari, Bari (Italy); Capitelli, M. [CNR IMIP Bari, Bari (Italy); Department of Chemistry, University of Bari, Bari (Italy)

    2012-06-15T23:59:59.000Z

    The cross sections for charge-exchange and charge-transfer processes are evaluated for collisions of helium ions with parent-atoms in ground and excited states, with the principal quantum number n= 1-5, in the collision energy range from thermal up to 10 eV. Corresponding diffusion-type collision integrals are derived, and the role of 'abnormal' transport of electronically excited states on the reactive thermal conductivity of equilibrium helium plasma, at atmospheric pressure, estimated in the frame of a simplified approach.

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

    E-Print Network [OSTI]

    Tiefenback, M.G.

    2011-01-01T23:59:59.000Z

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

  14. 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

    2009-01-22T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

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

    2003-12-01T23:59:59.000Z

    The effect of ion mass and charge state on plasma transport through a 90{sup o}-curved magnetic filter is experimentally investigated using a pulsed cathodic arc source. Graphite, copper, and tungsten were selected as test materials. The filter was a bent copper coil biased via the voltage drop across a low-ohm, ''self-bias'' resistor. Ion transport is accomplished via a guiding electric field, whose potential forms a ''trough'' shaped by the magnetic guiding field of the filter coil. Evaluation was done by measuring the filtered ion current and determination of the particle system coefficient, which can be defined as the ratio of filter ion current, divided by the mean ion charge state, to the arc current. It was found that the ion current and particle system coefficient decreased as the mass-to-charge ratio of ions increased. This result can be qualitatively interpreted by a very simply model of ion transport that is based on compensation of the centrifugal force by the electric force associated with the guiding potential trough.

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

    E-Print Network [OSTI]

    Tiefenback, M.G.

    2011-01-01T23:59:59.000Z

    35j. The output voltage droops in time as the charge on thethe ion gun apertures. Any droop in beam energy re­ sults in0.6 msec (0.15% per /zsec droop) is coupled to the various

  17. Charge transport through a SET with a mechanically oscillating island N. M. Chtchelkatchev,1, 2, 3

    E-Print Network [OSTI]

    Bruder, Christoph

    the deviation of the island from its equilibrium position. (b) Equivalent circuit of the device on the mechanical displacement, thus, the vibrations of the island may influence the transport properties. Harmonic oscillations of the island and thermal vibrations change the transport characteristics in different ways

  18. 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)

    2014-11-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Litzelman, Scott J

    2009-01-01T23:59:59.000Z

    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 ...

  20. Non-contact, non-destructive, quantitative probing of interfacial trap sites for charge carrier transport at semiconductor-insulator boundary

    SciTech Connect (OSTI)

    Choi, Wookjin; Miyakai, Tomoyo; Sakurai, Tsuneaki; Saeki, Akinori [Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita 565-0871 (Japan); Yokoyama, Masaaki [Kaneka Fundamental Technology Research Alliance Laboratories, Graduate School of Engineering, Osaka University, Suita 565-0871 (Japan); Seki, Shu, E-mail: seki@chem.eng.osaka-u.ac.jp [Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita 565-0871 (Japan); Kaneka Fundamental Technology Research Alliance Laboratories, Graduate School of Engineering, Osaka University, Suita 565-0871 (Japan)

    2014-07-21T23:59:59.000Z

    The density of traps at semiconductor–insulator interfaces was successfully estimated using microwave dielectric loss spectroscopy with model thin-film organic field-effect transistors. The non-contact, non-destructive analysis technique is referred to as field-induced time-resolved microwave conductivity (FI-TRMC) at interfaces. Kinetic traces of FI-TRMC transients clearly distinguished the mobile charge carriers at the interfaces from the immobile charges trapped at defects, allowing both the mobility of charge carriers and the number density of trap sites to be determined at the semiconductor-insulator interfaces. The number density of defects at the interface between evaporated pentacene on a poly(methylmethacrylate) insulating layer was determined to be 10{sup 12?}cm{sup ?2}, and the hole mobility was up to 6.5?cm{sup 2} V{sup ?1} s{sup ?1} after filling the defects with trapped carriers. The FI-TRMC at interfaces technique has the potential to provide rapid screening for the assessment of interfacial electronic states in a variety of semiconductor devices.

  1. 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

  2. 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)

    2012-01-15T23:59:59.000Z

    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.

  3. Mechanical and charge transport properties of alkanethiol self-assembled monolayers on Au (111) surface: The Role of Molecular Tilt

    SciTech Connect (OSTI)

    Mulleregan, Alice; Qi, Yabing; Ratera, Imma; Park, Jeong Y.; Ashby, Paul D.; Quek, Su Ying; Neaton, J. B.; Salmeron, Miquel

    2007-11-12T23:59:59.000Z

    The relationship between charge transport and mechanical properties of alkanethiol self-assembled monolayers (SAM) on Au(111) films has been investigated using an atomic force microscope with a conductive tip. Molecular tilts induced by the pressure applied by the tip cause stepwise increases in film conductivity. A decay constant {beta} = 0.57 {+-} 0.03 {angstrom}{sup -1} was found for the current passing through the film as a function of tip-substrate separation due to this molecular tilt. This is significantly smaller than the value of {approx} 1 {angstrom}{sup -1} found when the separation is changed by changing the length of the alkanethiol molecules. Calculations indicate that for isolated dithiol molecules S-bonded to hollow sites, the junction conductance does not vary significantly as a function of molecular tilt. The impact of S-Au bonding on SAM conductance is discussed.

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

    SciTech Connect (OSTI)

    Osses-Márquez, Juan; Calderón-Muñoz, Williams R., E-mail: wicalder@ing.uchile.cl [Department of Mechanical Engineering, University of Chile, Beauchef 850, Santiago (Chile)

    2014-10-21T23:59:59.000Z

    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.

  5. Effects of bulk charged impurities on the bulk and surface transport in three-dimensional topological insulators

    SciTech Connect (OSTI)

    Skinner, B.; Chen, T.; Shklovskii, B. I., E-mail: shklovsk@physics.spa.umn.edu [University of Minnesota, Fine Theoretical Physics Institute (United States)

    2013-09-15T23:59:59.000Z

    In the three-dimensional topological insulator (TI), the physics of doped semiconductors exists literally side-by-side with the physics of ultrarelativistic Dirac fermions. This unusual pairing creates a novel playground for studying the interplay between disorder and electronic transport. In this mini-review, we focus on the disorder caused by the three-dimensionally distributed charged impurities that are ubiquitous in TIs, and we outline the effects it has on both the bulk and surface transport in TIs. We present self-consistent theories for Coulomb screening both in the bulk and at the surface, discuss the magnitude of the disorder potential in each case, and present results for the conductivity. In the bulk, where the band gap leads to thermally activated transport, we show how disorder leads to a smaller-than-expected activation energy that gives way to variable-range hopping at low temperatures. We confirm this enhanced conductivity with numerical simulations that also allow us to explore different degrees of impurity compensation. For the surface, where the TI has gapless Dirac modes, we present a theory of disorder and screening of deep impurities, and we calculate the corresponding zero-temperature conductivity. We also comment on the growth of the disorder potential in passing from the surface of the TI into the bulk. Finally, we discuss how the presence of a gap at the Dirac point, introduced by some source of time-reversal symmetry breaking, affects the disorder potential at the surface and the mid-gap density of states.

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

    SciTech Connect (OSTI)

    Zhang, Z. D. [Department of Physics and Astronomy, SUNY Stony Brook, New York 11794 (United States); Wang, J. [Department of Physics and Astronomy, SUNY Stony Brook, New York 11794 (United States); Department of Chemistry, SUNY Stony Brook, New York 11794 (United States); State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022 (China)

    2014-06-28T23:59:59.000Z

    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. Populations of states give the probabilities of individual states and therefore quantify the population landscape. Both curl flux and coherence depend on steady state population landscape. 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. This is in contrast to the previously found linear relationship. For the systems coupled to bosonic (photonic and phononic) reservoirs the flux is significantly promoted at large voltage while for fermionic (electronic) reservoirs the flux reaches a saturation after a significant enhancement at large voltage due to the Pauli exclusion principle. 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.

  7. 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

    new single site molecular dynamics calculations to determine the time development of initialVersitaet Muenchen, Lichtenbergstrasse 4, D-85748 Garching, Germany, and Institute of Atomic and Molecular Science energization at an excitation site moving to a terminus. For this we find the efficiency of charge transport

  8. Received 10 May 2013 | Accepted 10 Oct 2013 | Published 8 Nov 2013 Probing single-to multi-cell level charge transport

    E-Print Network [OSTI]

    -cell level charge transport in Geobacter sulfurreducens DL-1 Xiaocheng Jiang1,*, Jinsong Hu2,*, Emily R energy into electricity, represent a potentially sustainable energy technology for the future. Here we report the single-bacterium level current measurements of Geobacter sulfurreducens DL-1 to elucidate

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

    SciTech Connect (OSTI)

    Wasielewski, Michael R. (NWU)

    2008-10-03T23:59:59.000Z

    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.

  10. Charge-carrier transport and recombination in heteroepitaxial CdTe

    SciTech Connect (OSTI)

    Kuciauskas, Darius, E-mail: Darius.Kuciauskas@nrel.gov; Farrell, Stuart; Dippo, Pat; Moseley, John; Moutinho, Helio; Li, Jian V.; Allende Motz, A. M.; Kanevce, Ana; Zaunbrecher, Katherine; Gessert, Timothy A.; Levi, Dean H.; Metzger, Wyatt K. [National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401-3305 (United States); Colegrove, Eric; Sivananthan, S. [Microphysics Laboratory, Physics Department, University of Illinois at Chicago, Chicago, Illinois 60612 (United States)

    2014-09-28T23:59:59.000Z

    We analyze charge-carrier dynamics using time-resolved spectroscopy and varying epitaxial CdTe thickness in undoped heteroepitaxial CdTe/ZnTe/Si. By employing one-photon and nonlinear two-photon excitation, we assess surface, interface, and bulk recombination. Two-photon excitation with a focused laser beam enables characterization of recombination velocity at the buried epilayer/substrate interface, 17.5??m from the sample surface. Measurements with a focused two-photon excitation beam also indicate a fast diffusion component, from which we estimate an electron mobility of 650?cm{sup 2} (Vs){sup ?1} and diffusion coefficient D of 17?cm{sup 2}?s{sup ?1}. We find limiting recombination at the epitaxial film surface (surface recombination velocity S{sub surface}?=?(2.8?±?0.3)?×?10{sup 5?}cm?s{sup ?1}) and at the heteroepitaxial interface (interface recombination velocity S{sub interface}?=?(4.8?±?0.5)?×?10{sup 5?}cm?s{sup ?1}). The results demonstrate that reducing surface and interface recombination velocity is critical for photovoltaic solar cells and electronic devices that employ epitaxial CdTe.

  11. Transportation

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

    Transportation Home Agenda Awards Exhibitors Lodging Posters Registration Transportation Workshops Contact Us User Meeting Archives Users' Executive Committee Getting to Berkeley...

  12. Transportation

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

    Transportation Print Home Agenda Awards Exhibitors Lodging Posters Registration Transportation Workshops Contact Us User Meeting Archives Users' Executive Committee Getting to...

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

    SciTech Connect (OSTI)

    Puthen-Veettil, B., E-mail: b.puthen-veettil@unsw.edu.au; Patterson, R.; König, D.; Conibeer, G.; Green, M. A. [Australian Centre for Advanced Photovoltaics, UNSW, Sydney 2052 (Australia)

    2014-10-28T23:59:59.000Z

    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/.

  14. Mean carrier transport properties and charge collection dynamics of single-crystal, natural type IIa diamonds from ion-induced conductivity measurements

    SciTech Connect (OSTI)

    Han, S.S.

    1993-09-01T23:59:59.000Z

    Ion-induced conductivity has been used to investigate the detector characteristics of diamond detectors. Both integrated-charge, and time-resolved current measurements were performed to examine the mean carrier transport properties of diamond and the dynamics of charge collection under highly-localized and high-density excitation conditions. The integrated-charge measurements were conducted with a standard pulse-counting system with {sup 241}Am radioactivity as the excitation source for the detectors. The time-resolved current measurements were performed using a 70 GHz random sampling oscilloscope with the detectors incorporated into high-speed microstrip transmission lines and the excitation source for these measurements was an ion beam of either 5-MeV He{sup +} or 10-MeV Si{sup 3+}. The detectors used in both experiments can be described as metal-semiconductor-metal (MSM) devices where a volume of the detector material is sandwiched between two metal plates. A charge collection model was developed to interpret the integrated-charge measurements which enabled estimation of the energy required to produce an electron-hole pair ({epsilon}{sub di}) and the mean carrier transport properties in diamond, such as carrier mobility and lifetime, and the behavior of the electrical contacts to diamond.

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

    SciTech Connect (OSTI)

    Das, B. K., E-mail: bdyt.ds@rediffmail.com; Hazarika, P.; Chakraborty, M. [Centre of Plasma Physics-Institute for Plasma Research, Tepesia-782402, Kamrup, Assam (India); Bandyopadhyay, M., E-mail: mainak@iter-india.org [ITER-India, Institute for Plasma Research, Gandhinagar-382025, Gujarat (India)

    2014-07-15T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

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

    2009-01-19T23:59:59.000Z

    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.

  17. 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)

    2014-02-15T23:59:59.000Z

    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.

  18. Transportation

    E-Print Network [OSTI]

    Vinson, Steve

    2013-01-01T23:59:59.000Z

    Transportation in ancient Egypt entailed the use of boats2007 Land transport in Roman Egypt: A study of economics andDieter 1991 Building in Egypt: Pharaonic stone masonry. New

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

    E-Print Network [OSTI]

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

    2012-01-01T23:59:59.000Z

    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...

  20. Research on defects and transport in amorphous silicon-based semiconductors. Annual subcontract report, 20 February 1991--19 February 1992

    SciTech Connect (OSTI)

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

    1992-04-01T23:59:59.000Z

    This report describes the results from research on two topics: (1) the effects of light-soaking on the electron drift mobility in a-Si:H, and (2) modulated electron spin resonance measurements and their relationship to the electronic correlation energy of the D center in a-Si:H. Both of these projects were undertaken to better determine where the ``standard`` model for a-Si:H breaks down. The standard model is reasonably successful in accounting for the most elementary ``deep trapping`` aspects of electron and hole transport in a-Si:H, and it accounts adequately for the sub-band-gap optical properties. However, it is much less clear whether it provides a sufficient basis for understanding several effects which are crucial in operating solar cells: electron and hole mobilities and recombination in the presence of light-bias and space-charge. In the standard model, one would not expect significant effects on drift mobilities due to light-soaking, which would be envisioned as simply increasing the D-center density. Similarly, in the standard model one would not anticipate a significant temperature dependence to electron spin resonance, because essentially all spins are already detected. Discussions in the available literature on the evidence regarding both effects were inconclusive. The work reported here sets considerably more stringent constraints on the magnitude of the two effects.

  1. Discrete torsion defects

    E-Print Network [OSTI]

    Ilka Brunner; Nils Carqueville; Daniel Plencner

    2014-09-15T23:59:59.000Z

    Orbifolding two-dimensional quantum field theories by a symmetry group can involve a choice of discrete torsion. We apply the general formalism of `orbifolding defects' to study and elucidate discrete torsion for topological field theories. In the case of Landau-Ginzburg models only the bulk sector had been studied previously, and we re-derive all known results. We also introduce the notion of `projective matrix factorisations', show how they naturally describe boundary and defect sectors, and we further illustrate the efficiency of the defect-based approach by explicitly computing RR charges. Roughly half of our results are not restricted to Landau-Ginzburg models but hold more generally, for any topological field theory. In particular we prove that for a pivotal bicategory, any two objects of its orbifold completion that have the same base are orbifold equivalent. Equivalently, from any orbifold theory (including those based on nonabelian groups) the original unorbifolded theory can be obtained by orbifolding via the `quantum symmetry defect'.

  2. 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 [Department of Chemistry, University of Alabama, 250 Hackberry Lane, Shelby hall, Tuscaloosa 35401 Alabama (United States); Yusoff, Mashitah M.; Jose, Rajan, E-mail: rjose@ump.edu.my [Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang, 26300 Kuantan (Malaysia)

    2014-10-13T23:59:59.000Z

    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.

  3. Novel chemical pathways and charge-transport dynamics of electrodes modified with electropolymerized layers of (Co(v-terpy)/sub 2/)/sup 2 +/

    SciTech Connect (OSTI)

    Guadalupe, A.R.; Usifer, D.A.; Potts, K.T.; Hurrell, H.C.; Mogstad, A.E.; Abruna, H.D.

    1988-05-25T23:59:59.000Z

    Electropolymerized films of (Co(v-terpy)/sub 2/)/sup 2 +/ (v-terpy is 4'-vinyl-2,2':6',2''-terpyridinyl) exhibit reactivity patterns, especially with regard to ligand exchange, that differ significantly from those exhibited by (Co(terpy)/sub 2/)/sup 2 +/ in solution. These differences are attributed to the physically constrained environment present in the polymer film. The charge-transport properties follow the model of Dahms and Ruff and the predicted concentration dependence of the diffusion coefficient. These electropolymerized films are also active in the electrocatalytic reduction of carbon dioxide.

  4. Determination of Dose From Light Charged Ions Relevant to Hadron Therapy Using the Particle and Heavy Ion Transport System (PHITS)

    E-Print Network [OSTI]

    Butkus, Michael Patrick

    2011-10-21T23:59:59.000Z

    .................................................................. 10 Quality Factor for Charged Particles .............................................. 13 Effects of Dose Fractionation ......................................................... 15 Fragmentation and Scattering... for Various Ion Beams ...................................................... 33 15 Dose Percentage Rates for Various Ion Beams in a Tumor and in Different Regions of a Body Relative to the Tumor .............................. 36 16 Quality Factors...

  5. 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

  6. The defect chemistry of nitrogen in oxides: A review of experimental and theoretical studies

    SciTech Connect (OSTI)

    Polfus, Jonathan M.; Norby, Truls [University of Oslo, Department of Chemistry, Centre for Materials Science and Nanotechnology (SMN), Gaustadalleen 21, FERMiO, NO-0349 Oslo (Norway)] [University of Oslo, Department of Chemistry, Centre for Materials Science and Nanotechnology (SMN), Gaustadalleen 21, FERMiO, NO-0349 Oslo (Norway); Haugsrud, Reidar, E-mail: reidarha@kjemi.uio.no [University of Oslo, Department of Chemistry, Centre for Materials Science and Nanotechnology (SMN), Gaustadalleen 21, FERMiO, NO-0349 Oslo (Norway)] [University of Oslo, Department of Chemistry, Centre for Materials Science and Nanotechnology (SMN), Gaustadalleen 21, FERMiO, NO-0349 Oslo (Norway)

    2013-02-15T23:59:59.000Z

    Incorporation of nitrogen into oxides has in recent years received increased attention as a variable for tuning their functional properties. A vast number of reports have been devoted to improving the photocatalytic properties of TiO{sub 2}, p-type charge carrier concentration in ZnO and the ionic transport properties of ZrO{sub 2} by nitrogen doping. In comparison, the fundamentals of the nitrogen related defect chemistry for a wider range of oxides have been less focused upon. In the present contribution, we review experimental and computational investigations of the nitrogen related defect chemistry of insulating and semiconducting oxides. The interaction between nitrogen and protons is important and emphasized. Specifically, the stability of nitrogen defects such as N{sub O}{sup /}, NH{sub O}{sup Multiplication-Sign} and (NH{sub 2}){sub O}{sup Bullet} is evaluated under various conditions and their atomistic and electronic structure is presented. A final discussion is devoted to the role of nitrogen with respect to transport properties and photocatalytic activity of oxides. - Graphical abstract: Experimental and theoretical investigations of the nitrogen related defect chemistry of a range of wide band gap oxides is reviewed. The interaction between nitrogen dopants and protons is emphasized and described through the atomistic and electronic structure as well as defect chemical processes involving NH and NH{sub 2} defects. Consequently, the physical properties of oxides containing such species are discussed with respect to e.g., diffusion and photocatalytic properties. Highlights: Black-Right-Pointing-Pointer Experimental and theoretical investigations of the nitrogen and hydrogen related defect chemistry of wide band gap oxides is reviewed. Black-Right-Pointing-Pointer The interaction between nitrogen dopants and protons is important and emphasized. Black-Right-Pointing-Pointer Diffusion and photocatalytic properties of N-doped oxides are discussed.

  7. An improved Monte Carlo study of coherent scattering effects of low energy charged particle transport in Percus-Yevick liquids

    E-Print Network [OSTI]

    Tattersall, W J; Boyle, G J; White, R D

    2015-01-01T23:59:59.000Z

    We generalize a simple Monte Carlo (MC) model for dilute gases to consider the transport behavior of positrons and electrons in Percus-Yevick model liquids under highly non-equilibrium conditions, accounting rigorously for coherent scattering processes. The procedure extends an existing technique [Wojcik and Tachiya, Chem. Phys. Lett. 363, 3--4 (1992)], using the static structure factor to account for the altered anisotropy of coherent scattering in structured material. We identify the effects of the approximation used in the original method, and develop a modified method that does not require that approximation. We also present an enhanced MC technique that has been designed to improve the accuracy and flexibility of simulations in spatially-varying electric fields. All of the results are found to be in excellent agreement with an independent multi-term Boltzmann equation solution, providing benchmarks for future transport models in liquids and structured systems.

  8. Scaling patterns for the suppression of charged hadron yields in Pb+Pb collisions at Root_s = 2.76 TeV: Constraints on transport coefficients

    E-Print Network [OSTI]

    Roy A. Lacey; N. N. Ajitanand; J. M. Alexander; J. Jia; A. Taranenko

    2012-02-24T23:59:59.000Z

    Suppression measurements for charged hadrons are used to investigate the path length (L) and transverse momentum (p_T) dependent jet quenching patterns of the hot and dense QCD medium produced in Pb+Pb collisions at Root_s =2.76 TeV at the LHC. The observed scaling patterns, which are similar to those observed for Au+Au collisions at Root_s = 0.20 TeV at RHIC, show the trends predicted for jet-medium interactions dominated by radiative energy loss. They also allow a simple estimate of the transport coefficient $\\hat{q}$, which suggests that the medium produced in LHC collisions is somewhat less opaque than that produced at RHIC, if the same parton-medium coupling strength is assumed. The higher temperature produced in LHC collisions could reduce the parton-medium coupling strength to give identical values for $\\hat{q}$ in LHC and RHIC collisions.

  9. 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

    2015-01-01T23:59:59.000Z

    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...

  10. Charge detection in semiconductor nanostructures

    E-Print Network [OSTI]

    MacLean, Kenneth (Kenneth MacLean, III)

    2010-01-01T23:59:59.000Z

    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 ...

  11. All optical method for investigation of spin and charge transport in semiconductors: Combination of spatially and time-resolved luminescence

    SciTech Connect (OSTI)

    Cadiz, F.; Paget, D.; Grebenkov, D.; Korb, J. P.; Rowe, A. C. H. [Physique de la matière condensée, Ecole Polytechnique, CNRS, 91128 Palaiseau (France); Barate, P.; Amand, T. [Université de Toulouse, INSA-CNRS-UPS, 31077 Toulouse Cedex (France); Arscott, S.; Peytavit, E. [Institut d'Electronique, de Microélectronique et de Nanotechnologie (IEMN), University of Lille, CNRS, Avenue Poincaré, Cité Scientifique, 59652 Villeneuve d'Ascq (France)

    2014-07-14T23:59:59.000Z

    A new approach is demonstrated for investigating charge and spin diffusion as well as surface and bulk recombination in unpassivated doped semiconductors. This approach consists in using two complementary, conceptually related, techniques, which are time-resolved photoluminescence (TRPL) and spatially resolved microluminescence (?PL) and is applied here to p{sup +} GaAs. Analysis of the sole TRPL signal is limited by the finite risetime. On the other hand, it is shown that joint TRPL and ?PL can be used to determine the diffusion constant, the bulk recombination time, and the spin relaxation time. As an illustration, the temperature variation of these quantities is investigated for p{sup +} GaAs.

  12. On the Defect Group of a 6D SCFT

    E-Print Network [OSTI]

    Michele Del Zotto; Jonathan J. Heckman; Daniel S. Park; Tom Rudelius

    2015-03-16T23:59:59.000Z

    We use the F-theory realization of 6D superconformal field theories (SCFTs) to study the corresponding spectrum of stringlike, i.e. surface defects. On the tensor branch, all of the stringlike excitations pick up a finite tension, and there is a corresponding lattice of string charges, as well as a dual lattice of charges for the surface defects. The defect group is data intrinsic to the SCFT and measures the surface defect charges which are not screened by dynamical strings. When non-trivial, it indicates that the associated theory has a partition vector rather than a partition function. We compute the defect group for all known 6D SCFTs, and find that it is just the abelianization of the discrete subgroup of U(2) which appears in the classification of 6D SCFTs realized in F-theory. We also explain how the defect group specifies defining data in the compactification of a (1,0) SCFT.

  13. International aeronautical user charges

    E-Print Network [OSTI]

    Odoni, Amedeo R.

    1985-01-01T23:59:59.000Z

    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 ...

  14. An Interfacial Complex in ZnO and Its Influence on Charge Transport Johan M Carlsson,1,* Helder S. Domingos,2

    E-Print Network [OSTI]

    Hellsing, Bo

    Physics, Chalmers University of Technology and Go¨teborg University, SE-412 96 Gothenburg, Sweden 2 2003) The segregation of native defects and Bi impurities to a high-angle grain boundary in Zn the concentration of native defects of acceptor type in the grain boundary. This leads to the formation of a Bi

  15. Defects activated photoluminescence in two-dimensional semiconductors

    E-Print Network [OSTI]

    Wu, Junqiao

    Defects activated photoluminescence in two-dimensional semiconductors: interplay between bound of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083, People's Republic of China, 3, Berkeley, California 94720, United States. Point defects in semiconductors can trap free charge carriers

  16. Current leakage relaxation and charge trapping in ultra-porous low-k materials

    SciTech Connect (OSTI)

    Borja, Juan; Plawsky, Joel L., E-mail: plawsky@rpi.edu; Gill, William N. [Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States); Lu, T.-M. [Department of Physics, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States); Bakhru, Hassaram [University at Albany's College of Nanoscale Science and Engineering (CNSE), Albany, New York 12203 (United States)

    2014-02-28T23:59:59.000Z

    Time dependent dielectric failure has become a pivotal aspect of interconnect design as industry pursues integration of sub-22?nm process-technology nodes. Literature has provided key information about the role played by individual species such as electrons, holes, ions, and neutral impurity atoms. However, no mechanism has been shown to describe how such species interact and influence failure. Current leakage relaxation in low-k dielectrics was studied using bipolar field experiments to gain insight into how charge carrier flow becomes impeded by defects within the dielectric matrix. Leakage current decay was correlated to injection and trapping of electrons. We show that current relaxation upon inversion of the applied field can be described by the stretched exponential function. The kinetics of charge trapping events are consistent with a time-dependent reaction rate constant, k=k{sub 0}?(t+1){sup ??1}, where 0?charge trapping reactions in amorphous solids by W. H. Hamill and K. Funabashi, Phys. Rev. B 16, 5523–5527 (1977). We explain the relaxation process in charge trapping events by introducing a nonlinear charge trapping model. This model provides a description on the manner in which the transport of mobile defects affects the long-tail current relaxation processes in low-k films.

  17. Effect of Niobium on the Defect Chemistry and Oxidation Kinetics of Tetragonal ZrO2

    E-Print Network [OSTI]

    Yildiz, Bilge

    Effect of Niobium on the Defect Chemistry and Oxidation Kinetics of Tetragonal ZrO2 Uuganbayar, Massachusetts 02139, United States ABSTRACT: Zirconium-niobium alloys are currently proposed for applications the effect of an extrinsic defect, niobium (Nb) dopant, on the defect equilibria and charge transfer

  18. Brake Defect Causation and Abatement Study (BDCAS)

    E-Print Network [OSTI]

    on various lining materials for comparison study #12;Center for Transportation Analysis 2360 CherahalaBrake Defect Causation and Abatement Study (BDCAS) Oak Ridge National Laboratory managed by UT Based Brake Testers (PBBTs) part of the out-of- service criterion for commercial motor vehicles in 2007

  19. 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)

    2012-10-23T23:59:59.000Z

    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.

  20. Pipeline charging of coke ovens with a preheated charge

    SciTech Connect (OSTI)

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

    1983-01-01T23:59:59.000Z

    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.

  1. 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)

    2014-04-07T23:59:59.000Z

    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.

  2. Quantum Chemical Analysis of Electronic Structure and n-and p-Type Charge Transport in Perfluoroarene-Modified Oligothiophene Semiconductors

    E-Print Network [OSTI]

    Medvedeva, Julia E.

    in Perfluoroarene-Modified Oligothiophene Semiconductors Sharon E. Koh, Bernard Delley, Julia E. Medvedeva isomeric fluoroarene-oligothiophene-based semiconductors. Three oligothiophene systems varying planarity plays a crucial role in the transport properties of these semiconductors. Our calculations

  3. Collective thermoelectrophoresis of charged colloids

    E-Print Network [OSTI]

    Arghya Majee; Alois Würger

    2014-01-29T23:59:59.000Z

    Thermally driven colloidal transport is, to a large extent, due to the thermoelectric or Seebeck effect of the charged solution.We show that, contrary to the generally adopted single-particle picture, the transport coefficient depends on the colloidal concentration. For solutions that are dilute in the hydrodynamic sense, collective effects may significantly affect the thermophoretic mobility. Our results provide an explanation for recent experimental observations on polyelectrolytes and charged particles and suggest that for charged colloids collective behavior is the rule rather than the exception.

  4. Fluctuation bounds on charge and heat diffusion

    E-Print Network [OSTI]

    Pavel Kovtun

    2014-07-02T23:59:59.000Z

    We study thermal fluctuation corrections to charge and heat conductivity in systems with locally conserved energy and charge, but without locally conserved momentum. Thermal fluctuations may naturally lead to a lower bound on diffusion constants for thermoelectric transport, and need to be taken into account when discussing potential bounds on transport coefficients.

  5. 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

    2012-09-03T23:59:59.000Z

    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 $\\sqrt{s_{NN}}$.

  6. 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]

    Heller, Eric

    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

  7. Do the Defects Make It Work? Defect Engineering in Pi-Conjugated Polymers and Their Solar Cells: Preprint

    SciTech Connect (OSTI)

    Wang, D.; Reese, M.; Kopidakis N.; Gregg, B. A.

    2008-05-01T23:59:59.000Z

    The charged defect density in common pi-conjugated polymers such as poly(3-hexylthiophene), P3HT, is around 1018 cm-3. Despite, or perhaps because of, this huge defect density, bulk heterojunction solar cells made from these polymers and a C60 derivative such as PCBM exhibit some of the highest efficiencies (~5%) yet obtained in solid state organic photovoltaic cells. We discuss defects in molecular organic semiconductors and in pi-conjugated polymers. These defects can be grouped in two categories, covalent and noncovalent. Somewhat analogous to treating amorphous silicon with hydrogen, we introduce chemical methods to modify the density and charge of the covalent defects in P3HT by treating it with electrophiles such as dimethyl sulfate and nucleophiles such as sodium methoxide. The effects of these treatments on the electrical and photovoltaic properties and stability of organic PV cells is discussed in terms of the change in the number and chemical properties of the defects. Finally, we address the question of whether the efficiency of OPV cells requires the presence of these defects which function as adventitious p-type dopants. Their presence relieves the resistance limitations usually encountered in cleaner organic semiconductors and can create built-in electric fields at junctions.

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

    DOE Patents [OSTI]

    2013-10-08T23:59:59.000Z

    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.

  9. Analysis of carrier transport and carrier trapping in organic diodes with polyimide-6,13-Bis(triisopropylsilylethynyl)pentacene double-layer by charge modulation spectroscopy and optical second harmonic generation measurement

    SciTech Connect (OSTI)

    Lim, Eunju, E-mail: elim@dankook.ac.kr, E-mail: taguchi.d.aa@m.titech.ac.jp, E-mail: iwamoto@pe.titech.ac.jp [Department of Applied Physics, Institute of Nanosensor and Biotechnology, Dankook University, Jukjeon-dong, Gyeonggi-do 448-701 (Korea, Republic of); Taguchi, Dai, E-mail: elim@dankook.ac.kr, E-mail: taguchi.d.aa@m.titech.ac.jp, E-mail: iwamoto@pe.titech.ac.jp; Iwamoto, Mitsumasa, E-mail: elim@dankook.ac.kr, E-mail: taguchi.d.aa@m.titech.ac.jp, E-mail: iwamoto@pe.titech.ac.jp [Department of Physical Electronics, Tokyo Institute of Technology 2-12-1, O-okayama, Meguro-ku, Tokyo 152-8552 (Japan)

    2014-08-18T23:59:59.000Z

    We studied the carrier transport and carrier trapping in indium tin oxide/polyimide (PI)/6,13-Bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene)/Au diodes by using charge modulation spectroscopy (CMS) and time-resolved electric field induced optical second harmonic generation (TR-EFISHG) measurements. TR-EFISHG directly probes the spatial carrier behaviors in the diodes, and CMS is useful in explaining the carrier motion with respect to energy. The results clearly indicate that the injected carriers move across TIPS-pentacene thorough the molecular energy states of TIPS-pentacene and accumulate at the PI/TIPS-pentacene interface. However, some carriers are trapped in the PI layers. These findings take into account the capacitance-voltage and current-voltage characteristics of the diodes.

  10. Effect of Ferroelectric Polarization on Ionic Transport and Resistance ...

    E-Print Network [OSTI]

    2014-07-18T23:59:59.000Z

    reliability of ceramic capacitors emerges as a critical chal- lenge when operation ... On the other hand, mathematical models of ionic/electronic defect transport ...

  11. Thermophoresis of charged colloidal particles

    E-Print Network [OSTI]

    S. Fayolle; T. Bickel; A. Würger

    2014-01-30T23:59:59.000Z

    Thermally induced particle flow in a charged colloidal suspension is studied in a fluid-mechanical approach. The force density acting on the charged boundary layer is derived in detail. From Stokes' equation with no-slip boundary conditions at the particle surface, we obtain the particle drift velocity and the thermophoretic transport coefficients. The results are discussed in view of previous work and available experimental data.

  12. Affine Defects and Gravitation

    E-Print Network [OSTI]

    R. J. Petti

    2014-12-12T23:59:59.000Z

    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.

  13. Role of defects in BiFeO{sub 3} multiferroic films and their local electronic structure by x-ray absorption spectroscopy

    SciTech Connect (OSTI)

    Ravalia, Ashish; Vagadia, Megha; Solanki, P. S.; Shah, N. A.; Kuberkar, D. G., E-mail: dgkuberkar@rediffmail.com [Department of Physics, Saurashtra University, Rajkot 360 005 (India); Gautam, S.; Chae, K. H. [Nano Material Analysis Centre, Korean Institute of Science and Technology, Seoul 136-79 (Korea, Republic of); Asokan, K. [Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110 067 (India)

    2014-10-21T23:59:59.000Z

    Present study reports the role of defects in the electrical transport in BiFeO{sub 3} (BFO) multiferroic films and its local electronic structure investigated by near-edge X-ray absorption fine structure. Defects created by high energy 200?MeV Ag{sup +15} ion irradiation with a fluence of ?5?×?10{sup 11} ions/cm{sup 2} results in the increase in structural strain and reduction in the mobility of charge carriers and enhancement in resistive (I-V) and polarization (P-E) switching behaviour. At higher fluence of ?5?×?10{sup 12} ions/cm{sup 2}, there is a release in the structural strain due to local annealing effect, resulting in an increase in the mobility of charge carriers, which are released from oxygen vacancies and hence suppression in resistive and polarization switching. Near-edge X-ray absorption fine structure studies at Fe L{sub 3,2}- and O K-edges show a significant change in the spectral features suggesting the modifications in the local electronic structure responsible for changes in the intrinsic magnetic moment and electrical transport properties of BFO.

  14. Piston-assisted charge pumping

    E-Print Network [OSTI]

    Kaur, D; Mourokh, L

    2015-01-01T23:59:59.000Z

    We examine charge transport through a system of three sites connected in series in the situation when an oscillating charged piston modulates the energy of the middle site. We show that with an appropriate set of parameters, charge can be transferred against an applied voltage. In this scenario, when the oscillating piston shifts away from the middle site, the energy of the site decreases and it is populated by a charge transferred from the lower energy site. On the other hand, when the piston returns to close proximity, the energy of the middle site increases and it is depopulated by the higher energy site. Thus through this process, the charge is pumped against the potential gradient. Our results can explain the process of proton pumping in one of the mitochondrial enzymes, Complex I. Moreover, this mechanism can be used for electron pumping in semiconductor nanostructures.

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

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

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

  16. Charged particle rapidity distributions at relativistic energies 

    E-Print Network [OSTI]

    Lin, ZW; Pal, S.; Ko, Che Ming; Li, Ba; Zhang, B.

    2001-01-01T23:59:59.000Z

    Using a multiphase transport model (AMPT), which includes both initial partonic and final hadronic interactions, we study the rapidity distributions of charged particles such as protons, antiprotons, pions, and kaons in heavy ion collisions at RHIC...

  17. Delocalised oxygen as the origin of two-level defects in Josephson junctions

    E-Print Network [OSTI]

    Timothy C. DuBois; Manolo C. Per; Salvy P. Russo; Jared H. Cole

    2012-12-07T23:59:59.000Z

    One of the key problems facing superconducting qubits and other Josephson junction devices is the decohering effects of bi-stable material defects. Although a variety of phenomenological models exist, the true microscopic origin of these defects remains elusive. For the first time we show that these defects may arise from delocalisation of the atomic position of the oxygen in the oxide forming the Josephson junction barrier. Using a microscopic model, we compute experimentally observable parameters for phase qubits. Such defects are charge neutral but have non-zero response to both applied electric field and strain. This may explain the observed long coherence time of two-level defects in the presence of charge noise, while still coupling to the junction electric field and substrate phonons.

  18. Electron tomography of defects

    E-Print Network [OSTI]

    Sharp, Joanne

    2010-10-12T23:59:59.000Z

    . . . . . . . . . . . . . . . . . . . 36 2.6 Limitations of electron tomography . . . . . . . . . . . . . . . 37 2.6.1 The missing wedge . . . . . . . . . . . . . . . . . . . . 37 2.6.2 Minimum reliable spacing of features . . . . . . . . . . 39 3 Tomography of dislocations using weak... ELECTRON TOMOGRAPHY OF DEFECTS This dissertation is submitted for the degree of Doctor of Philosophy by Joanne Sharp Of Wolfson College Submitted 26th April 2010 Acknowledgements This dissertation is the result of my own work and includes nothing...

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

    SciTech Connect (OSTI)

    Kova?evi?, Goran, E-mail: gkova@irb.hr; Pivac, Branko [Department of Materials Physics, Rudjer Boskovic Institute, Bijeni?ka 56, P.O.B. 180, HR-10002 Zagreb (Croatia)

    2014-01-28T23:59:59.000Z

    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.

  20. Defect mapping system

    DOE Patents [OSTI]

    Sopori, B.L.

    1995-04-11T23:59:59.000Z

    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.

  1. Managing Increased Charging Demand

    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 DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetterEconomyDr.Energy University Managing Increased Charging

  2. Electron and phonon renormalization near charged defects in carbon nanotubes

    E-Print Network [OSTI]

    Novotny, Lukas

    Technologies, Clemson University, Clemson, South Carolina 29621, USA 6 Divis~ao de Metrologia de Materiais, Instituto Nacional de Metrologia, Normalizac¸ ~ao e Qualidade Industrial (INMETRO), Duque de Caxias, RJ

  3. Friedel sum rule in the presence of topological defects for graphene

    E-Print Network [OSTI]

    Baishali Chakraborty; Kumar S. Gupta; Siddhartha Sen

    2014-03-20T23:59:59.000Z

    The Friedel sum rule is extended to deal with topological defects for the case of a graphene cone in the presence of an external Coulomb charge. The dependence in the way the number of states change due to both the topological defect as well as the Coulomb charge are studied. Our analysis addresses both the cases of a subcritical as well as a supercritical value of the Coulomb charge. We also discuss the experimental implications of introducing a self-adjoint extension of the system Hamiltonian. We argue that the boundary conditions following from the self-adjoint extension encode the effect of short range interactions present in the system.

  4. Electrochemical characterization of surface-bound redox polymers derived from 1,1'-bis(((3-(triethoxysilyl)propyl)amino)carbonyl)cobaltocenium: charge transport, anion binding, and use in photoelectrochemical hydrogen generation

    SciTech Connect (OSTI)

    Simon, R.A.; Mallouk, T.E.; Daube, K.A.; Wrighton, M.S.

    1985-09-25T23:59:59.000Z

    This paper describes the behavior of electrode-bound redox material derived from the hydrolysis of the -Si(OEt)/sub 3/ groups of 1,1'-bis(((3-(triethoxysilyl)propyl)amino)carbonyl)cobaltocenium (I). Surfaces of the conventional electrodes SnO/sub 2/ and Pt derivatized with I have a reversible electrochemical response in H/sub 2/O/electrolyte; the E/sup 0/' is pH independent at -0.62 V vs. SCE. The photoelectrochemical behavior of p-type Si photocathodes derivatized with I reveals that the photoreduction of the cobaltocenium derivative can be effected at an electrode potential approx. 500 mV more positive than on metallic electrodes, consistent with the known behavior of p-type Si photocathodes. When polymer from I is deposited on p-type Si and subsequently coated with a small amount of Rh or Pd (approx. 10/sup -7/ mol/cm/sup 2/), the photoelectrochemical generation of H/sub 2/ is possible with 632.8-nm (approx. 15 mW/cm/sup 2/) radiation and efficiencies in the vicinity of 2%. The polymer derived from I is more optically transparent and more durable at negative potentials than redox polymers derived from vilogen monomers. Potential-step measurements and steady-state-current measurements for mediated redox processes show that the charge-transport rate for the polymer derived from I is about the same as for polymers from viologen monomers. 32 references, 8 figures.

  5. Customer loyalty in the public transportation context

    E-Print Network [OSTI]

    Webb, Valerie (Valerie Nichole)

    2010-01-01T23:59:59.000Z

    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 ...

  6. A MOLECULAR ANALYSIS OF PROTEIN TRAFFICKING IN THE VERTEBRATE RETINA: IMPLICATIONS FOR INTRAFLAGELLAR TRANSPORT AND DISEASE

    E-Print Network [OSTI]

    Krock, Bryan L.

    2010-07-14T23:59:59.000Z

    trafficking. However, it was unclear whether photoreceptor degeneration in this disease is cell-autonomous, due to defective opsin transport within the photoreceptor, or is noncell-autonomous and a secondary consequence of defective RPE. Utilizing...

  7. AirTAP BriefingsA publication of the AirTAP program of the Center for Transportation Studies at the University of Minnesota Setting rates and charges can be one of

    E-Print Network [OSTI]

    Minnesota, University of

    at the University of Minnesota Setting rates and charges can be one of the most challenging tasks an airport services, and rates and charges can fluctu- ate depending on the types of services that are offered. Finally, if rates and charges are set too high at an airport, pilots can easily relocate their aircraft

  8. Who named the quantum defect?

    SciTech Connect (OSTI)

    Rau, A.R.P. [Louisiana State Univ., Baton Rouge, LA (United States). Dept. of Physics and Astronomy; Inokuti, M. [Argonne National Lab., IL (United States). Physics Div.

    1997-08-01T23:59:59.000Z

    The notion of the quantum defect is important in atomic and molecular spectroscopy and also in unifying spectroscopy with collision theory. In the latter context, the quantum defect may be viewed as an ancestor of the phase shift. However, the origin of the term quantum defect does not seem to be explained in standard textbooks. It occurred in a 1921 paper by Schroedinger, preceding quantum mechanics, yet giving the correct meaning as an index of the short-range interactions with the core of an atom. The authors present the early history of the quantum-defect idea, and sketch its recent developments.

  9. The Charging-Scheduling Problem for Electric Vehicle Networks

    E-Print Network [OSTI]

    The Charging-Scheduling Problem for Electric Vehicle Networks Ming Zhu, Xiao-Yang Liu, Linghe Kong}@sjtu.edu.cn Abstract--Electric vehicle (EV) is a promising transportation with plenty of advantages, e.g., low carbon method to reduce the total charging time for EVs. We study the Electric Vehicle Charging-Scheduling (EVCS

  10. Workplace Charging Challenge: Sample Workplace Charging Policy...

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

    guidelines used by one Workplace Charging Challenge partner to keep their program running safe and successfully. Sample Workplace Charging Policy More Documents & Publications...

  11. Conductivity maximum in a charged colloidal suspension

    SciTech Connect (OSTI)

    Bastea, S

    2009-01-27T23:59:59.000Z

    Molecular dynamics simulations of a charged colloidal suspension in the salt-free regime show that the system exhibits an electrical conductivity maximum as a function of colloid charge. We attribute this behavior to two main competing effects: colloid effective charge saturation due to counterion 'condensation' and diffusion slowdown due to the relaxation effect. In agreement with previous observations, we also find that the effective transported charge is larger than the one determined by the Stern layer and suggest that it corresponds to the boundary fluid layer at the surface of the colloidal particles.

  12. Combined Charge Carrier Transport and Photoelectrochemical Characteriz...

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

    valuable insight into this material as a photoanode. Citation: Rettie AJ, HC Lee, LG Marshall, JF Lin, C Capen, J Lindemuth, JS McCloy, J Zhou, AJ Bard, and CB...

  13. Energy Dissipation and Defect Generation for Nanocrystalline...

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

    Defect Generation for Nanocrystalline Silicon Carbide. Abstract: Large-scale molecular dynamics simulations have been employed to study defect generation and primary damage...

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

    SciTech Connect (OSTI)

    Gorai, Prashun; Seebauer, Edmund G., E-mail: eseebaue@illinois.edu [Department of Chemical and Biomolecular Engineering, University of Illinois, Urbana, Illinois 61801 (United States)

    2014-07-14T23:59:59.000Z

    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.

  15. First-principles core-level X-ray photoelectron spectroscopy calculation on arsenic defects in silicon crystal

    SciTech Connect (OSTI)

    Kishi, Hiroki; Miyazawa, Miki; Matsushima, Naoki; Yamauchi, Jun [Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Yokohama-shi, Kanagawa-ken 223-8522 (Japan)

    2014-02-21T23:59:59.000Z

    We investigate the X-ray photoelectron spectroscopy (XPS) binding energies of As 3d in Si for various defects in neutral and charged states by first-principles calculation. It is found that the complexes of a substitutional As and a vacancy in charged and neutral states explain the experimentally observed unknown peak very well.

  16. Topological Defects from the Multiverse

    E-Print Network [OSTI]

    Zhang, Jun; Garriga, Jaume; Vilenkin, Alexander

    2015-01-01T23:59:59.000Z

    Many theories of the early universe predict the existence of a multiverse where bubbles continuously nucleate giving rise to observers in their interior. In this paper, we point out that topological defects of several dimensionalities will also be produced in de Sitter like regions of the multiverse. In particular, defects could be spontaneously nucleated in our parent vacuum. We study the evolution of these defects as they collide with and propagate inside of our bubble. We estimate the present distribution of defects in the observable part of the universe. The expected number of such nearby defects turns out to be quite small, even for the highest nucleation rate. We also study collisions of strings and domain walls with our bubble in our past light cone. We obtain simulated full-sky maps of the loci of such collisions, and find their angular size distribution. Similarly to what happens in the case of bubble collisions, the prospect of detecting any collisions of our bubble with ambient defects is greatly e...

  17. Topological Defects from the Multiverse

    E-Print Network [OSTI]

    Jun Zhang; Jose J. Blanco-Pillado; Jaume Garriga; Alexander Vilenkin

    2015-01-22T23:59:59.000Z

    Many theories of the early universe predict the existence of a multiverse where bubbles continuously nucleate giving rise to observers in their interior. In this paper, we point out that topological defects of several dimensionalities will also be produced in de Sitter like regions of the multiverse. In particular, defects could be spontaneously nucleated in our parent vacuum. We study the evolution of these defects as they collide with and propagate inside of our bubble. We estimate the present distribution of defects in the observable part of the universe. The expected number of such nearby defects turns out to be quite small, even for the highest nucleation rate. We also study collisions of strings and domain walls with our bubble in our past light cone. We obtain simulated full-sky maps of the loci of such collisions, and find their angular size distribution. Similarly to what happens in the case of bubble collisions, the prospect of detecting any collisions of our bubble with ambient defects is greatly enhanced in the case where the cosmological constant of our parent vacuum is much higher than the vacuum energy density during inflation in our bubble.

  18. Fermion space charge in narrow-band gap semiconductors, Weyl semimetals and around highly charged nuclei

    E-Print Network [OSTI]

    Eugene B. Kolomeisky; Joseph P. Straley; Hussain Zaidi

    2013-10-15T23:59:59.000Z

    The field of charged impurities in narrow-band gap semiconductors and Weyl semimetals can create electron-hole pairs when the total charge $Ze$ of the impurity exceeds a value $Z_{c}e$. The particles of one charge escape to infinity, leaving a screening space charge. The result is that the observable dimensionless impurity charge $Q_{\\infty}$ is less than $Z$ but greater than $Z_{c}$. There is a corresponding effect for nuclei with $Z >Z_{c} \\approx 170$, however in the condensed matter setting we find $Z_{c} \\simeq 10$. Thomas-Fermi theory indicates that $Q_{\\infty} = 0$ for the Weyl semimetal, but we argue that this is a defect of the theory. For the case of a highly-charged recombination center in a narrow band-gap semiconductor (or of a supercharged nucleus), the observable charge takes on a nearly universal value. In Weyl semimetals the observable charge takes on the universal value $Q_{\\infty} = Z_{c}$ set by the reciprocal of material's fine structure constant.

  19. SciTech Connect: Atomistic mechanisms of rapid energy transport...

    Office of Scientific and Technical Information (OSTI)

    (fuels), solid state lighting, charge transport, materials and chemistry by design, optics, synthesis (novel materials), synthesis (self-assembly), synthesis (scalable...

  20. The Value of Flexibility in Robust Location-Transportation Problem

    E-Print Network [OSTI]

    2014-11-24T23:59:59.000Z

    Christensen, Tue R. L., Kim Allan Andersen, Andreas Klose. 2013. Solving the single-sink, fixed-charge, multiple-choice transportation problem by dynamic ...

  1. Nature of Radiation-Induced Defects in Quartz

    E-Print Network [OSTI]

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

    2015-04-10T23:59:59.000Z

    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.

  2. Charging Graphene for Energy Storage

    SciTech Connect (OSTI)

    Liu, Jun

    2014-10-06T23:59:59.000Z

    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.

  3. Defect CFTs and holographic multiverse

    E-Print Network [OSTI]

    Bartomeu Fiol

    2010-04-09T23:59:59.000Z

    We investigate some aspects of a recent proposal for a holographic description of the multiverse. Specifically, we focus on the implications on the suggested duality of the fluctuations of a bubble separating two universes with different cosmological constants. We do so by considering a similar problem in a 2+1 CFT with a codimension one defect, obtained by an M5-brane probe embedding in AdS_4x S^7, and studying its spectrum of fluctuations. Our results suggest that the kind of behavior required by the spectrum of bubble fluctuations is not likely to take place in defect CFTs with an AdS dual, although it might be possible if the defect supports a non-unitary theory.

  4. Defect CFTs and holographic multiverse

    SciTech Connect (OSTI)

    Fiol, Bartomeu, E-mail: bfiol@ub.edu [Departament de Física Fonamental i Institut de Ciències del Cosmos, Universitat de Barcelona, Martí i Franquès 1, 08193 Barcelona (Spain)

    2010-07-01T23:59:59.000Z

    We investigate some aspects of a recent proposal for a holographic description of the multiverse. Specifically, we focus on the implications on the suggested duality of the fluctuations of a bubble separating two universes with different cosmological constants. We do so by considering a similar problem in a 2+1 CFT with a codimension one defect, obtained by an M5-brane probe embedding in AdS{sub 4} × S{sup 7}, and studying its spectrum of fluctuations. Our results suggest that the kind of behavior required by the spectrum of bubble fluctuations is not likely to take place in defect CFTs with an AdS dual, although it might be possible if the defect supports a non-unitary theory.

  5. altered charge selectivity: Topics by E-print Network

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

    QD layer was more. In this study we show that p- and n-type inorganic charge transport thin films can be system- atically selected 5 Electrokinetic Instability near...

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

    E-Print Network [OSTI]

    Dworak, Jennifer

    2013-02-22T23:59:59.000Z

    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...

  7. Particle transport in plasma reactors

    SciTech Connect (OSTI)

    Rader, D.J.; Geller, A.S.; Choi, Seung J. [Sandia National Labs., Albuquerque, NM (United States); Kushner, M.J. [Illinois Univ., Urbana, IL (United States)

    1995-01-01T23:59:59.000Z

    SEMATECH and the Department of Energy have established a Contamination Free Manufacturing Research Center (CFMRC) located at Sandia National Laboratories. One of the programs underway at the CFMRC is directed towards defect reduction in semiconductor process reactors by the application of computational modeling. The goal is to use fluid, thermal, plasma, and particle transport models to identify process conditions and tool designs that reduce the deposition rate of particles on wafers. The program is directed toward defect reduction in specific manufacturing tools, although some model development is undertaken when needed. The need to produce quantifiable improvements in tool defect performance requires the close cooperation among Sandia, universities, SEMATECH, SEMATECH member companies, and equipment manufacturers. Currently, both plasma (e.g., etch, PECVD) and nonplasma tools (e.g., LPCVD, rinse tanks) are being worked on under this program. In this paper the authors summarize their recent efforts to reduce particle deposition on wafers during plasma-based semiconductor manufacturing.

  8. Local Transportation

    E-Print Network [OSTI]

    Local Transportation. Transportation from the Airport to Hotel. There are two types of taxi companies that operate at the airport: special and regular taxis (

  9. Greening Transportation

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

    Transportation Goal 2: Greening Transportation LANL supports and encourages employees to reduce their personal greenhouse gas emissions by offering various commuting and work...

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

    DOE Patents [OSTI]

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

    1995-06-20T23:59:59.000Z

    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.

  11. 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)

    1995-01-01T23:59:59.000Z

    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.

  12. 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.

    1998-07-28T23:59:59.000Z

    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.

  13. Anticorrelation between Surface and Subsurface Point Defects...

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

    between Surface and Subsurface Point Defects and the Impact on the Redox Chemistry of TiO2(110). Anticorrelation between Surface and Subsurface Point Defects and the...

  14. Inspection of lithographic mask blanks for defects

    DOE Patents [OSTI]

    Sommargren, Gary E. (Santa Cruz, CA)

    2001-01-01T23:59:59.000Z

    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.

  15. Chamber transport

    SciTech Connect (OSTI)

    OLSON,CRAIG L.

    2000-05-17T23:59:59.000Z

    Heavy ion beam transport through the containment chamber plays a crucial role in all heavy ion fusion (HIF) scenarios. Here, several parameters are used to characterize the operating space for HIF beams; transport modes are assessed in relation to evolving target/accelerator requirements; results of recent relevant experiments and simulations of HIF transport are summarized; and relevant instabilities are reviewed. All transport options still exist, including (1) vacuum ballistic transport, (2) neutralized ballistic transport, and (3) channel-like transport. Presently, the European HIF program favors vacuum ballistic transport, while the US HIF program favors neutralized ballistic transport with channel-like transport as an alternate approach. Further transport research is needed to clearly guide selection of the most attractive, integrated HIF system.

  16. Congestion control in charging of electric vehicles

    E-Print Network [OSTI]

    Carvalho, Rui; Gibbens, Richard; Kelly, Frank

    2015-01-01T23:59:59.000Z

    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.

  17. 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

    2015-01-01T23:59:59.000Z

    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.

  18. Method for mask repair using defect compensation

    DOE Patents [OSTI]

    Sweeney, Donald W. (San Ramon, CA); Ray-Chaudhuri, Avijit K. (Livermore, CA)

    2001-01-01T23:59:59.000Z

    A method for repair of amplitude and/or phase defects in lithographic masks. The method involves modifying or altering a portion of the absorber pattern on the surface of the mask blank proximate to the mask defect to compensate for the local disturbance (amplitude or phase) of the optical field due to the defect.

  19. Learning Defect Predictors:Lessons from the Trenches Learning Defect Predictors

    E-Print Network [OSTI]

    Menzies, Tim

    Learning Defect Predictors:Lessons from the Trenches Learning Defect Predictors: Lessons from the Trenches Tim Menzies LCSEE, WVU tim@menzies.us October 28, 2008 1 / 40 #12;Learning Defect Predictors:Lessons change the rules of the game. 2 / 40 #12;Learning Defect Predictors:Lessons from the Trenches

  20. Charge regulation circuit

    DOE Patents [OSTI]

    Ball, Don G. (Livermore, CA)

    1992-01-01T23:59:59.000Z

    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.

  1. Gravitational energy of conical defects

    E-Print Network [OSTI]

    J. W. Maluf; A. Kneip

    1996-08-22T23:59:59.000Z

    The energy density of asymptotically flat gravitational fields can be calculated from a simple expression involving the trace of the torsion tensor. Integration of this energy density over the whole space yields the ADM energy. Such expression can be justified within the framework of the teleparallel equivalent of general relativity, which is an alternative geometrical formulation of Einstein's general relativity. In this paper we apply this energy density to the evaluation of the energy per unit length of a class of conical defects of topological nature, which include disclinations and dislocations (in the terminology of crystallography). Disclinations correspond to cosmic strings, and for a spacetime endowed with only such a defect we obtain precisely the well known expression of energy per unit length. However for a pure spacetime dislocation the total gravitational energy is zero.

  2. Effects of topological defects and local curvature on the electronic properties of planar graphene

    E-Print Network [OSTI]

    Alberto Cortijo; María A. H. Vozmediano

    2006-12-14T23:59:59.000Z

    A formalism is proposed to study the electronic and transport properties of graphene sheets with corrugations as the one recently synthesized. The formalism is based on coupling the Dirac equation that models the low energy electronic excitations of clean flat graphene samples to a curved space. A cosmic string analogy allows to treat an arbitrary number of topological defects located at arbitrary positions on the graphene plane. The usual defects that will always be present in any graphene sample as pentagon-heptagon pairs and Stone-Wales defects are studied as an example. The local density of states around the defects acquires characteristic modulations that could be observed in scanning tunnel and transmission electron microscopy.

  3. Nature of Radiation-Induced Defects in Quartz

    E-Print Network [OSTI]

    Wang, Bu; Pignatelli, Isabella; Sant, Gaurav N; Bauchy, Mathieu

    2015-01-01T23:59:59.000Z

    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 dependenc...

  4. Defective flagellar assembly and length regulation in LF3 null mutants in Chlamydomonas

    E-Print Network [OSTI]

    Tam, Lai-Wa; Dentler Jr, William L.; Lefebvre, Paul A.

    2003-11-10T23:59:59.000Z

    defective in intraflagellar transport. We have cloned the wild-type LF3 gene and characterized a hypomorphic mutant allele of LF3. LF3p is a novel protein located predominantly in the cell body. It cosediments with the product of the LF1 gene in sucrose...

  5. Electrically charged pulsars

    E-Print Network [OSTI]

    M. D. Alloy; D. P. Menezes

    2007-04-24T23:59:59.000Z

    n the present work we investigate one possible variation on the usual electrically neutral pulsars: the inclusion of electric charge. We study the effect of electric charge in pulsars assuming that the charge distribution is proportional to the energy density. All calculations were performed for zero temperature and fixed entropy equations of state.

  6. Electric Vehicle Smart Charging Infrastructure

    E-Print Network [OSTI]

    Chung, Ching-Yen

    2014-01-01T23:59:59.000Z

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

  7. Electrostatic charging of lunar dust

    SciTech Connect (OSTI)

    Walch, Bob [Department of Physics, University of Northern Colorado, Greeley, Colorado 80639 (United States); Horanyi, Mihaly [LASP, University of Colorado, Boulder, Colorado 80309-0392 (United States); Robertson, Scott [Department of Physics, University of Colorado, Boulder, Colorado 80309-0391 (United States)

    1998-10-21T23:59:59.000Z

    Transient dust clouds suspended above the lunar surface were indicated by the horizon glow observed by the Surveyor spacecrafts and the Lunar Ejecta and Meteorite Experiment (Apollo 17), for example. The theoretical models cannot fully explain these observations, but they all suggest that electrostatic charging of the lunar surface due to exposure to the solar wind plasma and UV radiation could result in levitation, transport and ejection of small grains. We report on our experimental studies of the electrostatic charging properties of an Apollo-17 soil sample and two lunar simulants MLS-1 and JSC-1. We have measured their charge after exposing individual grains to a beam of fast electrons with energies in the range of 20{<=}E{<=}90 eV. Our measurements indicate that the secondary electron emission yield of the Apollo-17 sample is intermediate between MLS-1 and JSC-1, closer to that of MLS-1. We will also discuss our plans to develop a laboratory lunar surface model, where time dependent illumination and plasma bombardment will closely emulate the conditions on the surface of the Moon.

  8. Conformal nets III: fusion of defects

    E-Print Network [OSTI]

    Arthur Bartels; Christopher L. Douglas; André Henriques

    2015-02-21T23:59:59.000Z

    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. Environment Assisted Quantum Transport in Organic Molecules

    E-Print Network [OSTI]

    Vattay, Gabor

    2015-01-01T23:59:59.000Z

    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...

  10. 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)

    2014-01-01T23:59:59.000Z

    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.

  11. Evolution of Topological Defects During Inflation

    E-Print Network [OSTI]

    R. Basu; A. Vilenkin

    1994-02-22T23:59:59.000Z

    Topological defects can be formed during inflation by phase transitions as well as by quantum nucleation. We study the effect of the expansion of the Universe on the internal structure of the defects. We look for stationary solutions to the field equations, i.e. solutions that depend only on the proper distance from the defect core. In the case of very thin defects, whose core dimensions are much smaller than the de Sitter horizon, we find that the solutions are well approximated by the flat space solutions. However, as the flat space thickness parameter $\\delta_0$ increases we notice a deviation from this, an effect that becomes dramatic as $\\delta_0$ approaches $(H)^{-1}/{\\sqrt 2}$. Beyond this critical value we find no stationary solutions to the field equations. We conclude that only defects that have flat space thicknesses less than the critical value survive, while thicker defects are smeared out by the expansion.

  12. Space-time defects and teleparallelism

    E-Print Network [OSTI]

    J. W. Maluf; A. Goya

    2001-10-24T23:59:59.000Z

    We consider the class of space-time defects investigated by Puntigam and Soleng. These defects describe space-time dislocations and disclinations (cosmic strings), and are in close correspondence to the actual defects that arise in crystals and metals. It is known that in such materials dislocations and disclinations require a small and large amount of energy, respectively, to be created. The present analysis is carried out in the context of the teleparallel equivalent of general relativity (TEGR). We evaluate the gravitational energy of these space-time defects in the framework of the TEGR and find that there is an analogy between defects in space-time and in continuum material systems: the total gravitational energy of space-time dislocations and disclinations (considered as idealized defects) is zero and infinit, respectively.

  13. General Groves takes charge

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

    takes charge Colonel James C. Marshall, head of the DSM project (Development of Substitute Materials), did not make much headway, yet he did accomplish some things that lasted....

  14. Nano watermill driven by the revolving charge

    E-Print Network [OSTI]

    Zhou, Xiaoyan; Nie, Xuechuan; Wu, Fengmin; Liu, Yang; Lu, Hangjun

    2015-01-01T23:59:59.000Z

    Using molecular dynamics simulations, we propose a novel nanoscale watermill for unidirectional transport of water molecules through a curved single-walled carbon nanotube (SWNT). In this nanoscale system, a revolving charge is introduced to drive water chain confined inside the SWNT, which is served as nano waterwheel and nano engine. A resonance-like phenomenon is found that the revolving frequency of the charge plays a key role in pumping water chain. The water flux across the SWNT increases with respect to the revolving frequency of the external charge and reaches the maximum when the frequency is 4 THz. Correspondingly, the number of the hydrogen bonds of water chain inside the SWNT decreases dramatically with the frequency ranging from 4 THz to 25 THz. The mechanism behind the resonant phenomenon has been investigated systematically. Our findings are helpful for designing nanoscale fluidic devices and energy converters.

  15. Electrically charged compact stars

    E-Print Network [OSTI]

    Subharthi Ray; Manuel Malheiro; Jose' P. S. Lemos; Vilson T. Zanchin

    2006-04-17T23:59:59.000Z

    We review here the classical argument used to justify the electrical neutrality of stars and show that if the pressure and density of the matter and gravitational field inside the star are large, then a charge and a strong electric field can be present. For a neutron star with high pressure (~ 10^{33} to 10^{35} dynes /cm^2) and strong gravitational field (~ 10^{14} cm/s^2), these conditions are satisfied. The hydrostatic equation which arises from general relativity, is modified considerably to meet the requirements of the inclusion of the charge. In order to see any appreciable effect on the phenomenology of the neutron stars, the charge and the electrical fields have to be huge (~ 10^{21} Volts/cm). These stars are not however stable from the viewpoint that each charged particle is unbound to the uncharged particles, and thus the system collapses one step further to a charged black hole

  16. Charging Black Saturn?

    E-Print Network [OSTI]

    Brenda Chng; Robert Mann; Eugen Radu; Cristian Stelea

    2008-10-28T23:59:59.000Z

    We construct new charged static solutions of the Einstein-Maxwell field equations in five dimensions via a solution generation technique utilizing the symmetries of the reduced Lagrangian. By applying our method on the multi-Reissner-Nordstrom solution in four dimensions, we generate the multi-Reissner-Nordstrom solution in five dimensions. We focus on the five-dimensional solution describing a pair of charged black objects with general masses and electric charges. This solution includes the double Reissner-Nordstrom solution as well as the charged version of the five-dimensional static black Saturn. However, all the black Saturn configurations that we could find present either a conical singularity or a naked singularity. We also obtain a non-extremal configuration of charged black strings that reduces in the extremal limit to a Majumdar-Papapetrou like solution in five dimensions.

  17. Defect Analysis of Vehicle Compressed Natural Gas

    E-Print Network [OSTI]

    Defect Analysis of Vehicle Compressed Natural Gas Composite Cylinder A China Paper on Type 4;Industrial Computed Tomography (CT) Examination of Composite Gas Cylinder #12;CT of 01-01 Layer at 4.8MPa during the gas compressing and releasing processes are the direct causes for liner defect - Since

  18. DefectDomain Wall Interactions in Trigonal

    E-Print Network [OSTI]

    Gopalan, Venkatraman

    Defect­Domain Wall Interactions in Trigonal Ferroelectrics Venkatraman Gopalan,1 Volkmar Dierolf,2 walls in the trigonal ferroelectrics lithium niobate and lithium tantalate. It is shown that extrinsic questions re- garding intrinsic widths, defect­domain wall interactions, and static versus dynamic wall

  19. Predicting software defects in varying development lifecycles

    E-Print Network [OSTI]

    Bae, Doo-Hwan

    Predicting software defects in varying development lifecycles using Bayesian nets Information and Software Technology (2007) Norman Fenton, Martin Neil, William March, Peter HyeonJeong Kim KAIST SE LAB #12;Contents Introduction Overall approach Analyzing the lifecycle Modeling the defect prediction

  20. Computational Transportation

    E-Print Network [OSTI]

    Illinois at Chicago, University of

    ), in-vehicle computers, and computers in the transportation infrastructure are integrated ride- sharing, real-time multi-modal routing and navigation, to autonomous/assisted driving

  1. 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)

    2014-10-15T23:59:59.000Z

    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.

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

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

    Gasenzer, Thomas [Universitat Heidelberg, Institut fur Theoretische Physik, Heidelberg (Germany); GSI, ExtreMe Matter Institute EMMI, Darmstadt (Germany); McLerran, Larry [Brookhaven National Laboratory, Physics Department, RIKEN BNL Research Center Upton NY (United States); China Central Normal University, Physics Department, Wuhan (China); Pawlowski, Jan M [Universitat Heidelberg, Institut fur Theoretische Physik, Heidelberg (Germany); GSI, ExtreMe Matter Institute EMMI, Darmstadt (Germany); Sexty, Denes [Universitat Heidelberg, Institut fur Theoretische Physik, Heidelberg (Germany); GSI, ExtreMe Matter Institute EMMI, Darmstadt (Germany)

    2014-10-01T23:59:59.000Z

    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 Yang–Mills 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.

  3. 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, Dénes

    2014-10-01T23:59:59.000Z

    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 fixedmore »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 Yang–Mills 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

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

    E-Print Network [OSTI]

    Subramani, Praveen

    2012-01-01T23:59:59.000Z

    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 ...

  5. Synthesis and charge-transport properties of polymers derived from the oxidation of 1-hydro-1'-(6-(pyrrol-1-yl)hexyl)-4,4'-bipyridium Bis(hexafluorophosphate) and demonstration of pH-sensitive microelectrochemical transistor derived from the redox properties of a conventional redox center

    SciTech Connect (OSTI)

    Shu, C.F.; Wrighton, M.S.

    1988-09-08T23:59:59.000Z

    This article describes the synthesis and electrochemical properties of redox polymers, having a polypyrrole backbone and viologen subunits, derived from oxidative electropolymerization of 1-methyl-1'-(6-(pyrrol-1-yl)hexyl)-4,4'-bipyridinium (P-V-Me/sup 2 +/) and 1-hydro-1'-(6-(pyrrol-1-yl)hexyl)-4,4'-bipyridinium (P-V-H/sup 2 +/). Closely spaced (approx. 1.5 ..mu..M) Au microelectrode arrays (approx. 2.5 ..mu..m wide /times/ 50 ..mu..m long /times/ 0.1 ..mu..m high) modified with the polymers can be used to study aspects of the charge-transport behavior of the viologen redox system. Poly(P-V-Me/sup 2 +/) have been used to investigate the characteristics of microelectrochemical transistors based on a viologen redox center and a similar redox center, protonated, monoquaternized bipyridinium, which is pH dependent. The interesting properties from poly(P-V-Me/sup 2 +/) and poly(P-V-H/sup 2 +/) stem from behavior of the pendant viologen redox centers. The device based on poly(P-V-Me/sup 2 +/) has a narrow region (approx. 200 mV) of gate voltage, V/sub G/, where the source-drain current, I/sub D/, is nonzero and has a sharp, pH-independent peak in the I/sub D/-V/sub G/ plot at approx. 0.53 V versus SCE associated with the reversible, one-electron reduction of viologen. This result is consistent with electron self-exchange between redox centers being the mechanism for charge transport. The device based on poly(P-V-H/sup 2 +/) shows a pH-dependent I/sub D/ at fixed V/sub G/, as expected from the electrochemical behavior from reversible protonation of the terminal N of the bipyridinium group of poly(P-V-H/sup 2 +/). The microelectrochemical transistor based on poly(P-V-H/sup 2 +/) illustrates the design of chemically sensitive, molecule-based devices using conventional redox materials.

  6. Radioactive Fission Product Release from Defective Light Water Reactor Fuel Elements

    SciTech Connect (OSTI)

    Konyashov, Vadim V.; Krasnov, Alexander M. [State Scientific Centre of Russian Federation-Research Institute of Atomic Reactors (Russian Federation)

    2002-04-15T23:59:59.000Z

    Results are provided of the experimental investigation of radioactive fission product (RFP) release, i.e., krypton, xenon, and iodine radionuclides from fuel elements with initial defects during long-term (3 to 5 yr) irradiation under low linear power (5 to 12 kW/m) and during special experiments in the VK-50 vessel-type boiling water reactor.The calculation model for the RFP release from the fuel-to-cladding gap of the defective fuel element into coolant was developed. It takes into account the convective transport in the fuel-to-cladding gap and RFP sorption on the internal cladding surface and is in good agreement with the available experimental data. An approximate analytical solution of the transport equation is given. The calculation dependencies of the RFP release coefficients on the main parameters such as defect size, fuel-to-cladding gap, temperature of the internal cladding surface, and radioactive decay constant were analyzed.It is shown that the change of the RFP release from the fuel elements with the initial defects during long-term irradiation is, mainly, caused by fuel swelling followed by reduction of the fuel-to-cladding gap and the fuel temperature. The calculation model for the RFP release from defective fuel elements applicable to light water reactors (LWRs) was developed. It takes into account the change of the defective fuel element parameters during long-term irradiation. The calculation error according to the program does not exceed 30% over all the linear power change range of the LWR fuel elements (from 5 to 26 kW/m)

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

    E-Print Network [OSTI]

    Dworak, Jennifer Lynn

    2004-09-30T23:59:59.000Z

    defect detection. We deterministically maximize the observations of the leastobserved sites while randomly exciting the defects that may be present. The resulting decrease in defective part level is estimated using the MPGD model. This dissertation...

  8. Relativistic Dynamics of a Charged Particle in an Electroscalar Field

    E-Print Network [OSTI]

    D. V. Podgainy; O. A. Zaimidoroga

    2012-03-12T23:59:59.000Z

    This article devoted to relativistic dynamics of a charged massive particle in an electroscalar field. It represents a continuation of paper [1] where the authors constructed a non-relativistic theory which describes transverse electromagnetic waves along with longitudinal electroscalar ones, responsible for the wave transport of the Coulomb field. A new type of relativistic force exerted by electroscalar field on an electrically charged particle and the relativistic law of superposition of electromagnetic transverse and electroscalar longitudinal fields are established. Also, a relativistically invariant form of a Lagrangian describing the interaction between an electroscalar field and massive electrically charged particle is defined.

  9. Relativistic Dynamics of a Charged Particle in an Electroscalar Field

    E-Print Network [OSTI]

    Podgainy, D V

    2012-01-01T23:59:59.000Z

    This article devoted to relativistic dynamics of a charged massive particle in an electroscalar field. It represents a continuation of paper [1] where the authors constructed a non-relativistic theory which describes transverse electromagnetic waves along with longitudinal electroscalar ones, responsible for the wave transport of the Coulomb field. A new type of relativistic force exerted by electroscalar field on an electrically charged particle and the relativistic law of superposition of electromagnetic transverse and electroscalar longitudinal fields are established. Also, a relativistically invariant form of a Lagrangian describing the interaction between an electroscalar field and massive electrically charged particle is defined.

  10. Defect classes - an overdue paradigm for CMOS IC testing

    SciTech Connect (OSTI)

    Hawkins, C.F. [Univ. of New Mexico, Albuquerque, NM (United States); Soden, J.M.; Righter, A.W. [Sandia National Labs., Albuquerque, NM (United States); Ferguson, F.J. [Univ. of California, Santa Cruz, CA (United States)

    1994-09-01T23:59:59.000Z

    The IC test industry has struggled for more than 30 years to establish a test approach that would guarantee a low defect level to the customer. We propose a comprehensive strategy for testing CMOS ICs that uses defect classes based on measured defect electrical properties. Defect classes differ from traditional fault models. Our defect class approach requires that the test strategy match the defect electrical properties, while fault models require that IC defects match the fault definition. We use data from Sandia Labs failure analysis and test facilities and from public literature. We describe test pattern requirements for each defect class and propose a test paradigm.

  11. Defect Distribution and Dissolution Morphologies on Low-Index...

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

    Defect Distribution and Dissolution Morphologies on Low-Index Surfaces of alpha-Quartz . Defect Distribution and Dissolution Morphologies on Low-Index Surfaces of alpha-Quartz ....

  12. Energetics of Defects on Graphene through Fluorination. | EMSL

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

    Defects on Graphene through Fluorination. Energetics of Defects on Graphene through Fluorination. Abstract: In the present study, we used FGS5 as the substrate and implemented...

  13. Exploring the interaction between lithium ion and defective graphene...

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

    Exploring the interaction between lithium ion and defective graphene surface using dispersion corrected DFT studies. Exploring the interaction between lithium ion and defective...

  14. Modification of Defect Structures in Graphene by Electron Irradiation...

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

    Modification of Defect Structures in Graphene by Electron Irradiation: Ab Initio Molecular Dynamics Simulations. Modification of Defect Structures in Graphene by Electron...

  15. Role of Point Defects on the Reactivity of Reconstructed Anatase...

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

    Point Defects on the Reactivity of Reconstructed Anatase Titanium Dioxide (001) Surface. Role of Point Defects on the Reactivity of Reconstructed Anatase Titanium Dioxide (001)...

  16. Transportation Market Distortions

    E-Print Network [OSTI]

    Litman, Todd

    2006-01-01T23:59:59.000Z

    of Highways, Volpe National Transportation Systems Center (Evaluating Criticism of Transportation Costing, VictoriaFrom Here: Evaluating Transportation Diversity, Victoria

  17. Abstract adiabatic charge pumping

    E-Print Network [OSTI]

    A. Joye; V. Brosco; F. Hekking

    2010-02-05T23:59:59.000Z

    This paper is devoted to the analysis of an abstract formula describing quantum adiabatic charge pumping in a general context. We consider closed systems characterized by a slowly varying time-dependent Hamiltonian depending on an external parameter $\\alpha$. The current operator, defined as the derivative of the Hamiltonian with respect to $\\alpha$, once integrated over some time interval, gives rise to a charge pumped through the system over that time span. We determine the first two leading terms in the adiabatic parameter of this pumped charge under the usual gap hypothesis. In particular, in case the Hamiltonian is time periodic and has discrete non-degenerate spectrum, the charge pumped over a period is given to leading order by the derivative with respect to $\\alpha$ of the corresponding dynamical and geometric phases.

  18. Annealing behaviors of vacancy-type defects near interfaces between metal contacts and GaN probed using a monoenergetic positron beam

    SciTech Connect (OSTI)

    Uedono, Akira, E-mail: uedono.akira.gb@u.tsukuba.ac.jp; Yoshihara, Nakaaki [Division of Applied Physics, Faculty of Pure and Applied Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan); Fujishima, Tatsuya; Piedra, Daniel; Palacios, Tomás [Microsystems Technology Laboratories, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307 (United States); Ishibashi, Shoji [Nanosystem Research Institute “RICS,” National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568 (Japan); Sumiya, Masatomo [Wide Bandgap Material Group, National Institute for Materials Science, Tsukuba 305-0044 (Japan); Laboutin, Oleg; Johnson, Wayne [IQE, 200 John Hancock Road, Taunton, Massachusetts 01581 (United States)

    2014-08-04T23:59:59.000Z

    Vacancy-type defects near interfaces between metal contacts and GaN grown on Si substrates by metal organic chemical vapor deposition have been studied using a monoenergetic positron beam. Measurements of Doppler broadening spectra of the annihilation radiation for Ti-deposited GaN showed that optically active vacancy-type defects were introduced below the Ti/GaN interface after annealing at 800?°C. Charge transition of those defects due to electron capture was observed and was found to correlate with a yellow band in the photoluminescence spectrum. The major defect species was identified as vacancy clusters such as three to five Ga-vacancies coupled with multiple nitrogen-vacancies. The annealing behaviors of vacancy-type defects in Ti-, Ni-, and Pt-deposited GaN were also examined.

  19. Electrically charged targets

    DOE Patents [OSTI]

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

    1984-01-01T23:59:59.000Z

    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.

  20. 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)

    2011-12-26T23:59:59.000Z

    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.

  1. Understanding dopant and defect effect on H2S sensing performances of graphene: A first-principles study

    E-Print Network [OSTI]

    Guo, John Zhanhu

    Understanding dopant and defect effect on H2S sensing performances of graphene: A first November 2012 Accepted 29 November 2012 Keywords: Graphene H2S Sensor Electron transport a b s t r a c t The interaction between hydrogen sulfite (H2S) and graphene was investigated by density functional the- ory

  2. Di-interstitial defect in silicon revisited

    SciTech Connect (OSTI)

    Londos, C. A.; Antonaras, G. [Solid State Section, Physics Department, University of Athens, Panepistimiopolis, Zografos, 157 84 Athens (Greece)] [Solid State Section, Physics Department, University of Athens, Panepistimiopolis, Zografos, 157 84 Athens (Greece); Chroneos, A. [Engineering and Innovation, The Open University, Milton Keynes MK7 6AA (United Kingdom) [Engineering and Innovation, The Open University, Milton Keynes MK7 6AA (United Kingdom); Department of Materials, Imperial College London, London SW7 2BP (United Kingdom)

    2013-11-21T23:59:59.000Z

    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.

  3. Generalized quantum defect methods in quantum chemistry

    E-Print Network [OSTI]

    Altunata, Serhan

    2006-01-01T23:59:59.000Z

    The reaction matrix of multichannel quantum defect theory, K, gives a complete picture of the electronic structure and the electron - nuclear dynamics for a molecule. The reaction matrix can be used to examine both bound ...

  4. Sandia National Laboratories: Defect-Carrier Interactions

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

    with SSLS scientist Andy Armstrong using deep level optical spectroscopy to investigate defects in the m-plane GaN. Jim is a professor ... Last Updated: September 6, 2013...

  5. Two-dimensional defects in amorphous materials

    E-Print Network [OSTI]

    Michael Moshe; Eran Sharon; Ido Levin; Hillel Aharoni; Raz Kupferman

    2014-09-09T23:59:59.000Z

    We present a new definition of defects which is based on a Riemannian formulation of incompatible elasticity. Defects are viewed as local deviations of the material's reference metric field, $\\bar{\\mathfrak{g}}$, from a Euclidian metric. This definition allows the description of defects in amorphous materials and the formulation of the elastic problem, using a single field, $\\bar{\\mathfrak{g}}$. We provide a multipole expansion of reference metrics that represent a large family of two-dimensional (2D) localized defects. The case of a dipole, which corresponds to an edge dislocation is studied analytically, experimentally and numerically. The quadrupole term, which is studied analytically, as well as higher multipoles of curvature carry local deformations. These multipoles are good candidates for fundamental strain carrying entities in plasticity theories of amorphous materials and for a continuous modeling of recently developed meta-materials.

  6. Defect analysis using resonant ultrasound spectroscopy 

    E-Print Network [OSTI]

    Flynn, Kevin Joseph

    2009-05-15T23:59:59.000Z

    This thesis demonstrates the practicability of using Resonant Ultrasound Spectroscopy (RUS) in combination with Finite Element Analysis (FEA) to determine the size and location of a defect in a material of known geometry ...

  7. 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)

    2010-02-22T23:59:59.000Z

    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.

  8. electrifyingthefuture transportation

    E-Print Network [OSTI]

    Birmingham, University of

    electrifyingthefuture transportation The UK Government's carbon reduction strategy vehicles and the new Birmingham Science City Energy Systems Integration Laboratory (ESIL) will further enhance this work. The laboratory - unique within the UK and world leading - brings together cutting edge

  9. Quick charge battery

    SciTech Connect (OSTI)

    Parise, R.J.

    1998-07-01T23:59:59.000Z

    Electric and hybrid electric vehicles (EVs and HEVs) will become a significant reality in the near future of the automotive industry. Both types of vehicles will need a means to store energy on board. For the present, the method of choice would be lead-acid batteries, with the HEV having auxiliary power supplied by a small internal combustion engine. One of the main drawbacks to lead-acid batteries is internal heat generation as a natural consequence of the charging process as well as resistance losses. This limits the re-charging rate to the battery pack for an EV which has a range of about 80 miles. A quick turnaround on recharge is needed but not yet possible. One of the limiting factors is the heat buildup. For the HEV the auxiliary power unit provides a continuous charge to the battery pack. Therefore heat generation in the lead-acid battery is a constant problem that must be addressed. Presented here is a battery that is capable of quick charging, the Quick Charge Battery with Thermal Management. This is an electrochemical battery, typically a lead-acid battery, without the inherent thermal management problems that have been present in the past. The battery can be used in an all-electric vehicle, a hybrid-electric vehicle or an internal combustion engine vehicle, as well as in other applications that utilize secondary batteries. This is not restricted to only lead-acid batteries. The concept and technology are flexible enough to use in any secondary battery application where thermal management of the battery must be addressed, especially during charging. Any battery with temperature constraints can benefit from this advancement in the state of the art of battery manufacturing. This can also include nickel-cadmium, metal-air, nickel hydroxide, zinc-chloride or any other type of battery whose performance is affected by the temperature control of the interior as well as the exterior of the battery.

  10. Holographic Charge Oscillations

    E-Print Network [OSTI]

    Mike Blake; Aristomenis Donos; David Tong

    2014-12-05T23:59:59.000Z

    The Reissner-Nordstrom black hole provides the prototypical description of a holographic system at finite density. We study the response of this system to the presence of a local, charged impurity. Below a critical temperature, the induced charge density, which screens the impurity, exhibits oscillations. These oscillations can be traced to the singularities in the density-density correlation function moving in the complex momentum plane. At finite temperature, the oscillations are very similar to the Friedel oscillations seen in Fermi liquids. However, at zero temperature the oscillations in the black hole background remain exponentially damped, while Friedel oscillations relax to a power-law

  11. Overview of charge symmetry

    SciTech Connect (OSTI)

    Miller, G.A. [Department of Physics, FM-15, University of Washington, Seattle, Washington 98195 (United States)

    1995-07-15T23:59:59.000Z

    Charge independence and symmetry are approximate symmetries of nature. The observations of the small charge symmetry breaking effects and the consequences of those effects are reviewed. The effects of the mass difference between up and down quarks and the off shell dependence {ital q}{sup 2} of {rho}{sup 0}-{omega} mixing are stressed. We find that models which predict a strong {ital q}{sup 2} dependence of {rho}{sup 0}-{omega} mixing seem also to predict a strong {ital q}{sup 2} variation for the {rho}{sup 0}-{gamma}* matrix element, in contradiction with experiment.

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

    E-Print Network [OSTI]

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

    2007-01-16T23:59:59.000Z

    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.

  13. Influence of defects on thermal and mechanical properties of metals

    E-Print Network [OSTI]

    Kamani, Sandeep Kumar

    2009-05-15T23:59:59.000Z

    SDen ..................................... 33 13 Copper with 8 interstitials at 1600K ....................................................... 34 14 Temperature Vs time for copper without defects at 1360K .................... 39 15 Potential energy Vs time for copper without defects... at 1360K .............. 40 16 Total energy Vs time for copper without defects at 1360K .................... 40 17 Average volume Vs temperature for pure copper without defects .......... 41 18 Total energy Vs temperature for copper without defects...

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

    E-Print Network [OSTI]

    uni-directional wind turbine fiber-reinforced composite material with an epoxy resin were utilized of wind turbine blades have essentially dictated the use of low cost fiberglass composite materials. Even1 Manufacturing Defects Common to Composite Wind Turbine Blades: Effects of Defects Jared W. Nelson

  15. 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

  16. Gated charged-particle trap

    DOE Patents [OSTI]

    Benner, W. Henry (Danville, CA)

    1999-01-01T23:59:59.000Z

    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.

  17. AVTA: Siemens-VersiCharge AC Level 2 Charging System Testing...

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

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

  18. Structural and energy characteristics of native vacancy-type defects in the biaxially stressed GaN lattice

    SciTech Connect (OSTI)

    Bez'yazychnaya, T. V.; Zelenkovskii, V. M.; Gurskii, A. L.; Ryabtsev, G. I. [National Academy of Sciences of Belarus, Stepanov Institute of Physics (Belarus)], E-mail: ryabtsev@dragon.bas-net.by

    2008-11-15T23:59:59.000Z

    For biaxially stressed GaN clusters, the structure, charges, and energies of the formation of intrinsic Ga and N vacancies are calculated by the quantum-chemical method in the SCF MO LCAO approximation taking into account relaxation of the crystalline surroundings. It is established that the use of substrates introducing compressive or tensile stresses into the epitaxial layer affects the concentrations of intrinsic vacancy-type point defects. This effect most clearly manifests itself in the nitrogen sublattice in the GaN crystal lattice, especially in the case of its tension, i.e., during the epitaxial grown of GaN on the Si substrate. Redistribution of the electron density in the defect region in the case of lattice compression or tension can be the cause of variation in the location of electronic levels of defects in the band gap of the crystal.

  19. The effects of fastener hole defects

    E-Print Network [OSTI]

    Andrews, Scot D.

    1991-01-01T23:59:59.000Z

    ) 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...

  20. Dirac oscillator interacting with a topological defect

    SciTech Connect (OSTI)

    Carvalho, J.; Furtado, C.; Moraes, F. [Unidade Academica de Tecnologia de Alimentos, CCTA, Universidade Federal de Campina Grande, Pereiros, 58840-000, Pombal, Paraiba (Brazil); Departamento de Fisica, CCEN, Universidade Federal da Paraiba, Cidade Universitaria, 58051-970 Joao Pessoa, Paraiba (Brazil)

    2011-09-15T23:59:59.000Z

    In this work we study the interaction problem of a Dirac oscillator with gravitational fields produced by topological defects. The energy levels of the relativistic oscillator in the cosmic string and in the cosmic dislocation space-times are sensible to curvature and torsion associated to these defects and are important evidence of the influence of the topology on this system. In the presence of a localized magnetic field the energy levels acquire a term associated with the Aharonov-Bohm effect. We obtain the eigenfunctions and eigenvalues and see that in the nonrelativistic limit some results known in standard quantum mechanics are reached.

  1. Bistable defect structures in blue phase devices

    E-Print Network [OSTI]

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

    2011-10-28T23:59:59.000Z

    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.

  2. GaN: Defect and Device Issues

    SciTech Connect (OSTI)

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

    1998-11-09T23:59:59.000Z

    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.

  3. Role of collector alternating charged patches on transport of...

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

    microsphere in 2-dimensional micromodels was studied. The cylindrical silica collectors within the micromodels were coated with 0, 10, 20, 50 and 100% Fe2O3 patches. The...

  4. 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.

    2002-01-01T23:59:59.000Z

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

  5. 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)

    2014-11-01T23:59:59.000Z

    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.

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

    Office of Environmental Management (EM)

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 1112011AT&T, Inc.'sEnergyTexas1. Feedstock & ProductionChapter 6 --3078Met-Ocean

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

    Office of Environmental Management (EM)

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 1112011AT&T, Inc.'sEnergyTexas1. Feedstock & ProductionChapter 6 --3078Met-Oceanof

  8. Charge-carrier transport in amorphous organic semiconductors

    E-Print Network [OSTI]

    Limketkai, Benjie, 1982-

    2008-01-01T23:59:59.000Z

    Since the first reports of efficient luminescence and absorption in organic semiconductors, organic light-emitting devices (OLEDs) and photovoltaics (OPVs) have attracted increasing interest. Organic semiconductors have ...

  9. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) EnvironmentalGyroSolé(tm)HydrogenRFP »summerlecturesVortices InfluenceInfluence

  10. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWPSuccessAlamosCharacterization of Selective Binding of2 DOE

  11. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041clothAdvanced Materials Advanced. C o w l i t z CPlasma of the Rotating Wall Machine by

  12. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742Energy China U.S. Department ofJuneWasteDepartmentUtilities in many statesChapter 78Desert3

  13. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del(ANL-IN-03-032) -Less isNFebruaryOctober 2, AlgeriaQ1 Q2you aA Deep Diveinin

  14. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn Other News link to facebookInfinibandVorticesChange

  15. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn Other News link to

  16. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn Other News link toInfluence of Topological Spin Fluctuations

  17. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn Other News link toInfluence of Topological Spin

  18. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn Other News link toInfluence of Topological SpinInfluence of

  19. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.NewofGeothermal Heat Annual Report, 1993Semiconductor | Stanford

  20. Direct observation of the topological charge of a terahertz vortex beam generated by a Tsurupica spiral phase plate

    SciTech Connect (OSTI)

    Miyamoto, K., E-mail: k-miyamoto@faculty.chiba-u.jp [Graduate School of Advanced Integration Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522 (Japan); Suizu, K.; Akiba, T. [Department of Electrical, Electronics and Computer Engineering, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016 (Japan); Omatsu, T. [Graduate School of Advanced Integration Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522 (Japan); CREST Japan Science and Technology Agency, Sanbancho, Chiyoda-ku, Tokyo 102-0075 (Japan)

    2014-06-30T23:59:59.000Z

    A terahertz (THz) spiral phase plate with high transmission (>90% after Fresnel correction) and low dispersion has been developed based on the Tsurupica olefin polymer. Direct observations of the topological charge (both magnitude and sign) of a THz vortex beam are performed by using a THz camera with tilted lens focusing and radial defect introduction. The vortex outputs with a topological charge of ±1 (or ±2) are obtained at a frequency of 2 (or 4) THz.

  1. Texas State Planning Region 3 Report of Regional Transportation Coordination

    E-Print Network [OSTI]

    Nortex Regional Planning Commission

    2006-12-01T23:59:59.000Z

    of the 24 regions studying public transportation in their area was charged with assessing Barriers, Constraints and Best Practices in public transportation. This Coordination Committee addressed this issue with enthusiasm, generating significant topics...DOT requirement that all vehicles be ADA compliant, Medicaid restrictions and Insurance as significant barriers to public transportation. Best practices included sharing of information regarding this project through publication in rural newspapers, inter...

  2. Transportation and its Infrastructure

    E-Print Network [OSTI]

    2007-01-01T23:59:59.000Z

    40 pp. IEA, 2004c: Biofuels for Transport: An Internationalthe ACT Map scenario, transport biofuels production reachesestimates that biofuels’ share of transport fuel could

  3. General 2 charge geometries

    E-Print Network [OSTI]

    Marika Taylor

    2005-07-22T23:59:59.000Z

    Two charge BPS horizon free supergravity geometries are important in proposals for understanding black hole microstates. In this paper we construct a new class of geometries in the NS1-P system, corresponding to solitonic strings carrying fermionic as well as bosonic condensates. Such geometries are required to account for the full microscopic entropy of the NS1-P system. We then briefly discuss the properties of the corresponding geometries in the dual D1-D5 system.

  4. Properties of native defects in InI for potential radiation detector application

    SciTech Connect (OSTI)

    Biswas, Koushik [ORNL; Du, Mao-Hua [ORNL

    2011-01-01T23:59:59.000Z

    Heavy-metal halide semiconductors have attracted much interest recently for their potential applications in radiation detection because the large atomic numbers (high Z) of their constituent elements enable efficient radiation absorption and their large band gaps allow room temperature operation. However, defect properties of these halides and their connection to carrier transport are little known. In this paper, we present first-principles calculations on native defects in InI, which is a promising material for applications in room temperature radiation detection. The important findings are: (1) anion and cation vacancies (Schottky defects) form the dominant low-energy defects that can pin the Fermi level close to midgap, leading to high resistivity that is required for a good radiation detector material; (2) the anion vacancy in InI induces a deep electron trap, which should reduce electron mobility-lifetime product in InI; (3) low diffusion barriers of vacancies could be responsible for the observed polarization phenomenon at room temperature

  5. On the Proton charge extensions

    E-Print Network [OSTI]

    M. Gluck

    2015-02-03T23:59:59.000Z

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

  6. Triplet Transport to and Trapping by Acceptor End Groups on Conjugated Polyfluorene Chains

    SciTech Connect (OSTI)

    Sreearunothai, P.; Miller, J.; Estrada, A.; Asaoka, S.; Kowalczyk, M.; Jang, S.; Cook, A.R.; Preses, J.M.

    2011-08-31T23:59:59.000Z

    Triplet excited states created in polyfluorene (pF) molecules having average lengths up to 170 repeat units were transported to and captured by trap groups at the ends in less {approx}40 ns. Almost all of the triplets attached to the chains reached the trap groups, ruling out the presence of substantial numbers of defects that prevent transport. The transport yields a diffusion coefficient D of at least 3 x 10{sup -4} cm{sup 2} s{sup -1}, which is 30 times typical molecular diffusion and close to a value for triplet transport reported by Keller (J. Am. Chem. Soc.2011, 133, 11289-11298). The triplet states were created in solution by pulse radiolysis; time resolution was limited by the rate of attachment of triplets to the pF chains. Naphthylimide (NI) or anthraquinone (AQ) groups attached to the ends of the chains acted as traps for the triplets, although AQ would not have been expected to serve as a trap on the basis of triplet energies of the separate molecules. The depths of the NI and AQ triplet traps were determined by intermolecular triplet transfer equilibria and temperature dependence. The trap depths are shallow, just a few times thermal energy for both, so a small fraction of the triplets reside in the pF chains in equilibrium with the end-trapped triplets. Trapping by AQ appears to arise from charge transfer interactions between the pF chains and the electron-accepting AQ groups. Absorption bands of the end-trapped triplet states are similar in peak wavelength (760 nm) and shape to the 760 nm bands of triplets in the pF chains but have reduced intensities. When an electron donor, N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD), is added to the solution, it reacts with the end-trapped triplets to remove the 760 nm bands and to make the trapping irreversible. New bands created upon reaction with TMPD may be due to charge transfer states.

  7. Tools for charged Higgs bosons

    E-Print Network [OSTI]

    Oscar Stål

    2010-12-13T23:59:59.000Z

    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.

  8. Increasing the creation yield of shallow single defects in diamond by surface plasma treatment

    SciTech Connect (OSTI)

    Osterkamp, Christian; Scharpf, Jochen; Naydenov, Boris; Jelezko, Fedor [Institut für Quantenoptik, Ulm University, Albert Einstein Allee 11, Ulm 89081 (Germany)] [Institut für Quantenoptik, Ulm University, Albert Einstein Allee 11, Ulm 89081 (Germany); Pezzagna, Sebastien; Meijer, Jan [Institut für Experimentelle Physik II, Abteilung Nukleare Festkörperphysik, Universität Leipzig, Linnestraße 5, Leipzig 04103 (Germany)] [Institut für Experimentelle Physik II, Abteilung Nukleare Festkörperphysik, Universität Leipzig, Linnestraße 5, Leipzig 04103 (Germany); Diemant, Thomas; Jürgen Behm, Rolf [Institut für Oberflächenchemie und Katalyse, Ulm University, Albert-Einstein-Allee 47, Ulm 89081 (Germany)] [Institut für Oberflächenchemie und Katalyse, Ulm University, Albert-Einstein-Allee 47, Ulm 89081 (Germany)

    2013-11-04T23:59:59.000Z

    Single Nitrogen-Vacancy (NV) centers in diamond close to the crystal surface are very promising magnetic field sensors with very high sensitivity. Here, we report the enhanced creation of very shallow (less than 3 nm below the diamond surface) NV centers by using fluorine and oxygen plasma treatment. We observe a four fold increase—from 0.11% to about 0.45% in the production yield when the sample surface is terminated with fluorine or oxygen atoms. This effect is explained by the stabilization of the NV's negative charge state which is influenced by the various defects present on the diamond surface.

  9. Atomic-Level Computer Simulation of SiC: Defect Accumulation...

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

    Atomic-Level Computer Simulation of SiC: Defect Accumulation, Mechanical Properties and Defect Recovery. Atomic-Level Computer Simulation of SiC: Defect Accumulation, Mechanical...

  10. NREL: Transportation Research - Transportation and Hydrogen Newsletter...

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

    The Future of Sustainable Transportation This is the January 2015 issue of the Transportation and Hydrogen Newsletter. Illustration of an electric vehicle Illustration of an...

  11. 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.

    2012-06-01T23:59:59.000Z

    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.

  12. Dynamics of Non-adiabatic Charged Cylindrical Gravitational Collapse

    E-Print Network [OSTI]

    M. Sharif; G. Abbas

    2011-07-30T23:59:59.000Z

    This paper is devoted to study the dynamics of gravitational collapse in the Misner and Sharp formalism. We take non-viscous heat conducting charged anisotropic fluid as a collapsing matter with cylindrical symmetry. The dynamical equations are derived and coupled with the transport equation for heat flux obtained from the M$\\ddot{u}$ller-Israel-Stewart causal thermodynamic theory. We discuss the role of anisotropy, electric charge and radial heat flux over the dynamics of the collapse with the help of coupled equation.

  13. Defect- and Strain-enhanced Cavity Formation and Au Precipitation...

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

    Defect- and Strain-enhanced Cavity Formation and Au Precipitation at nano-crystalline ZrO2SiO2Si Interfaces . Defect- and Strain-enhanced Cavity Formation and Au Precipitation at...

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

    E-Print Network [OSTI]

    Dorsey, David Michael

    2004-09-30T23:59:59.000Z

    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 ...

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

    E-Print Network [OSTI]

    Rice, Marie C

    2014-01-01T23:59:59.000Z

    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 ...

  16. Automated Diagnosis and Classification of Steam Generator Tube Defects

    SciTech Connect (OSTI)

    Dr. Gabe V. Garcia

    2004-10-01T23:59:59.000Z

    A major cause of failure in nuclear steam generators is tube degradation. Tube defects are divided into seven categories, one of which is intergranular attack/stress corrosion cracking (IGA/SCC). Defects of this type usually begin on the outer surface of the tubes and propagate both inward and laterally. In many cases these defects occur at or near the tube support plates. Several different methods exist for the nondestructive evaluation of nuclear steam generator tubes for defect characterization.

  17. 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 DataDepartment of Energy Your Density Isn't Your Destiny: The FutureComments from TarasaName4ServicesTribalWorkplace Charging Summit

  18. NERSC 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |IsLove Your1AllocationsNOVA Portal: Submit2014 2015Charging HPSS

  19. 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)

    2012-05-22T23:59:59.000Z

    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.

  20. NREL: Transportation Research - Transportation News

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for Renewable Energy: Grid IntegrationReportTransmissionResearchNewsTransportation News

  1. Collective phenomena in defect crystals Reimer Kuhn1,

    E-Print Network [OSTI]

    Kühn, Reimer

    by quantum effects. Both thermal and dynamical properties are considered. The influence of interactions Talence cedex, France Received 25 April 2000 We investigate the effects of interactions between substitutional defects on the properties of defect crystals at low temperatures, where defect motion is governed

  2. Critical Area Computation for Missing Material Defects in VLSI Circuits

    E-Print Network [OSTI]

    Papadopoulou, Evanthia

    Critical Area Computation for Missing Material Defects in VLSI Circuits Evanthia Papadopoulou IBM the problem of computing critical area for miss- ing material defects in a circuit layout. The extraction of critical area is the main computational problem in VLSI yield prediction. Missing material defects cause

  3. 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...

  4. Oxygen Transport Ceramic Membranes

    SciTech Connect (OSTI)

    S. Bandopadhyay; N. Nagabhushana; Thomas W. Eagar; Harold R. Larson; Raymundo Arroyave; X.-D Zhou; Y.-W. Shin; H.U. Anderson; Nigel Browning; Alan Jacobson; C.A. Mims

    2003-11-01T23:59:59.000Z

    The present quarterly report describes some of the initial studies on newer compositions and also includes newer approaches to address various materials issues such as in metal-ceramic sealing. The current quarter's research has also focused on developing a comprehensive reliability model for predicting the structural behavior of the membranes in realistic conditions. In parallel to industry provided compositions, models membranes have been evaluated in varying environment. Of importance is the behavior of flaws and generation of new flaws aiding in fracture. Fracture mechanics parameters such as crack tip stresses are generated to characterize the influence of environment. Room temperature slow crack growth studies have also been initiated in industry provided compositions. The electrical conductivity and defect chemistry of an A site deficient compound (La{sub 0.55}Sr{sub 0.35}FeO{sub 3}) was studied. A higher conductivity was observed for La{sub 0.55}Sr{sub 0.35}FeO{sub 3} than that of La{sub 0.60}Sr{sub 0.40}FeO{sub 3} and La{sub 0.80}Sr{sub 0.20}FeO{sub 3}. Defect chemistry analysis showed that it was primarily contributed by a higher carrier concentration in La{sub 0.55}Sr{sub 0.35}FeO{sub 3}. Moreover, the ability for oxygen vacancy generation is much higher in La{sub 0.55}Sr{sub 0.35}FeO{sub 3} as well, which indicates a lower bonding strength between Fe-O and a possible higher catalytic activity for La{sub 0.55}Sr{sub 0.35}FeO{sub 3}. The program continued to investigate the thermodynamic properties (stability and phase separation behavior) and total conductivity of prototype membrane materials. The data are needed together with the kinetic information to develop a complete model for the membrane transport. Previous report listed initial measurements on a sample of La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-x} prepared in-house by Praxair. Subsequently, a second sample of powder from a larger batch of sample were characterized and compared with the results from the previous batch.

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

    Energy Savers [EERE]

    The report also examines when consumers want to recharge vehicles, and to what extent pricing and incentives can encourage consumers to charge during off-peak periods. Evaluating...

  6. Transmissive optomechanical platforms with engineered spatial defects

    E-Print Network [OSTI]

    Edoardo Tignone; Guido Pupillo; Claudiu Genes

    2014-06-23T23:59:59.000Z

    We investigate the optomechanical photon-phonon coupling of a single light mode propagating through an array of vibrating mechanical elements. As recently shown for the particular case of a periodic array of membranes embedded in a high-finesse optical cavity [A. Xuereb, C. Genes and A. Dantan, Phys. Rev. Lett., \\textbf{109}, 223601, (2012)], the intracavity linear optomechanical coupling can be considerably enhanced over the single element value in the so-called \\textit{transmissive regime}, where for motionless membranes the whole system is transparent to light. Here, we extend these investigations to quasi-periodic arrays in the presence of engineered spatial defects in the membrane positions. In particular we show that the localization of light modes induced by the defect combined with the access of the transmissive regime window can lead to additional enhancement of the strength of both linear and quadratic optomechanical couplings.

  7. Metastable light induced defects in pentacene

    SciTech Connect (OSTI)

    Liguori, R.; Aprano, S.; Rubino, A. [Department of Industrial Engineering (DIIn), University of Salerno, via Giovanni Paolo II, 132, 84084 Fisciano (Italy)

    2014-02-21T23:59:59.000Z

    In this study we analyzed one of the environmental factors that could affect organic materials. Pentacene thin film samples were fabricated and the degradation of their electrical characteristics was measured when the devices were exposed to ultraviolet light irradiation. The results have been reported in terms of a trap density model, which provides a description of the dynamics of light induced electrically active defects in an organic semiconductor.

  8. Defect suppression from the compound semiconductor heterointerfaces

    SciTech Connect (OSTI)

    Kalem, S. [TUBITAK-Marmara Research Center, Gebze (Turkey); Curtis, A.; Hartmann, Q.J.; Thomas, S.; Turnbull, D.; Chuang, H.; Bishop, S.G.; Stillman, G.E. [Univ. of Illinois, Urbana, IL (United States). Center for Compound Semiconductor Microelectronics

    1996-12-31T23:59:59.000Z

    The authors report on the effect of inserting ultra-thin InAs layers at the heterointerfaces on physical properties of GaAs/InGaP on GaAs and InP/GaAs on InP grown by MOCVD and MOMBE, respectively. It is shown that the insertion of ultra thin InAs layers at the heterostructure interfaces has a significant effect in eliminating defects from the interfaces.

  9. Topological defects and electronic properties in graphene

    E-Print Network [OSTI]

    Alberto Cortijo; María A. H. Vozmediano

    2006-12-14T23:59:59.000Z

    In this work we will focus on the effects produced by topological disorder on the electronic properties of a graphene plane. The presence of this type of disorder induces curvature in the samples of this material, making quite difficult the application of standard techniques of many body quantum theory. Once we understand the nature of these defects, we can apply ideas belonging to quantum field theory in curved space-time and extract information on physical properties that can be measured experimentally.

  10. 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)

    1996-01-01T23:59:59.000Z

    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.

  11. Further investigation of the characteristics of nodular defects

    SciTech Connect (OSTI)

    Liu Xiaofeng; Li Dawei; Zhao Yuan'an; Li Xiao

    2010-04-01T23:59:59.000Z

    To increase the understanding of the damage sensitivity of nodular defects and provide exact evidence for theoretical study, the structures and the damage behavior of nodular defects in electron-beam deposited mirrors of HfO2/SiO2 are systemically investigated with a double-beam microscope (focused ion beam, scanning electron microscope). Nodular defects are classified into two kinds. In one kind the boundaries between nodules and the surrounding layers have become continuous for the last deposited materials, and in the other there are discontinuous boundaries between nodules and the surrounding layers. Nodular defects of the first kind typically have low domes, and the second have high domes. Laser damage experiments show that nodular defects of the first kind usually have a high laser resistance, and the laser-induced damage thresholds are limited in the second class of nodules. The dominant parameter of nodular defects related to damage is the height of the nodular defect.

  12. Charge exchange molecular ion source

    DOE Patents [OSTI]

    Vella, Michael C.

    2003-06-03T23:59:59.000Z

    Ions, particularly molecular ions with multiple dopant nucleons per ion, are produced by charge exchange. An ion source contains a minimum of two regions separated by a physical barrier and utilizes charge exchange to enhance production of a desired ion species. The essential elements are a plasma chamber for production of ions of a first species, a physical separator, and a charge transfer chamber where ions of the first species from the plasma chamber undergo charge exchange or transfer with the reactant atom or molecules to produce ions of a second species. Molecular ions may be produced which are useful for ion implantation.

  13. 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. [Cornell University, Ithaca, New York 14853 (United States)

    2014-07-28T23:59:59.000Z

    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 ?560–720?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.

  14. Sacrificial Charge and Charge Injection! Evolution of Line Width!

    E-Print Network [OSTI]

    Grant, Catherine E.

    . Similar structures are seen in the energy scale due to sacrificial charge. " Solar Min Solar Max increasing CTI, trailing charge and event/split thresholds Evolution of Energy Scale! · Radiation damage! Catherine Grant, Bev LaMarr, Eric Miller and Mark Bautz (MIT Kavli Institute)! Instruments and Data! · Front

  15. Pulverization Induced Charge: In-Line Dry Coal Cleaning

    SciTech Connect (OSTI)

    Schaefer, J.L.; Stencel, J.M.

    1997-05-13T23:59:59.000Z

    The technical feasibility of separating mineral matter and pyrite from coal as it is transported from pulverizers to boilers in pulverized coal combustion units will be examined. The charge imparted on coal during pulverization and transport to pulverized coal (PC) burners in a utility boiler will be quantified. In addition to field charge measurements, an existing computational model will be extended to numerically simulate charged particle motion in a turbulent gas through an electric field. Results from the field tests and numerical modeling will be employed in design and construction of a laboratory scale pulverizer/classifier. This laboratory unit will be used to quantify the magnitude and differential charge imparted on bituminous and subbituminous coals during pulverization and classification at temperatures and with gaseous constituents typical to utility PC units. An electrostatic separator, designed for in-line operation between pulverizers and PC boilers, will be used to clean prepulverized coals. Theoretical and experimental data are to be used in preparing a preliminary design for a full-scale, (15 ton/hr) in-line, electrostatic coal cleaning device. Finally, the economic potential for application to PC units will be assessed.

  16. PULVERIZATION INDUCED CHARGE: IN-LINE DRY COAL CLEANING

    SciTech Connect (OSTI)

    JOHN M. STENCEL

    1998-07-01T23:59:59.000Z

    The technical feasibility of separating mineral matter and pyrite from coal as it is transported from pulverizers to burners in pulverized coal combustion units will be examined. The charge imparted on coal during pulverization and transport to pulverized coal (PC) burners in a utility boiler will be quantified. In addition to field charge measurements, an existing computational model will be extended to numerically simulate charged particle motion in a turbulent gas through an electric field. Results from the field tests and numerical modeling will be employed in design and construction of a laboratory scale pulverizer/classifier. This laboratory unit will be used to quantify the magnitude and differential charge imparted on bituminous and subbituminous coals during pulverization and classification at temperatures and with gaseous constituents typical to utility PC units. An electrostatic separator, designed for in-line operation between pulverizers and PC boilers, will be used to clean prepulverized coals. Theoretical and experimental data are to be used in preparing a preliminary design for a full-scale, (15 ton/hr) in-line, electrostatic coal cleaning device. Finally, the economic potential for application to PC units will be assessed.

  17. Pulverization Induced Charge: In-Line Dry Coal Cleaning

    SciTech Connect (OSTI)

    John M. Stencel

    1998-05-26T23:59:59.000Z

    The technical feasibility of separating mineral matter and pyrite from coal as it is transported from pulverizers to burners in pulverized coal combustion units will be examined. The charge imparted on coal during pulverization and transport to pulverized coal (PC) burners in a utility boiler will be quantified. In addition to field charge measurements, an existing computational model will be extended to numerically simulate charged particle motion in a turbulent gas through an electric field. Results from the field tests and numerical modeling will be employed in design and construction of a laboratory scale pulverizer/classifier. This laboratory unit will be used to quantify the magnitude and differential charge imparted on bituminous and subbituminous coals during pulverization and classification at temperatures and with gaseous constituents typical to utility PC units. An electrostatic separator, designed for in-line operation between pulverizers and PC boilers, will be used to clean prepulverized coals. Theoretical and experimental data are to be used in preparing a preliminary design for a full-scale, (15 ton/hr) in-line, electrostatic coal cleaning device. Finally, the economic potential for application to PC units will be assessed.

  18. Pulverization Induced Charge: In-Line Dry Coal Cleaning

    SciTech Connect (OSTI)

    John M. Stencel

    1998-01-21T23:59:59.000Z

    The technical feasibility of separating mineral matter and pyrite from coal as it is transported from pulverizers to burners in pulverized coal combustion units will be examined. The charge imparted on coal during pulverization and transport to pulverized coal (PC) burners in a utility boiler will be quantified. In addition to field charge measurements, an existing computational model will be extended to numerically simulate charged particle motion in a turbulent gas through an electric field. Results from the field tests and numerical modeling will be employed in design and construction of a laboratory scale pulverizer/classifier. This laboratory unit will be used to quantify the magnitude and differential charge imparted on bituminous and subbituminous coals during pulverization and classification at temperatures and with gaseous constituents typical to utility PC units. An electrostatic separator, designed for in-line operation between pulverizers and PC boilers, will be used to clean prepulverized coals. Theoretical and experimental data are to be used in preparing a preliminary design for a full-scale, (15 ton/hr) in-line, electrostatic coal cleaning device. Finally, the economic potential for application to PC units will be assessed.

  19. Transporting particulate material

    DOE Patents [OSTI]

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

    2011-08-30T23:59:59.000Z

    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.

  20. Charge exchange recombination spectroscopy on fusion devices

    SciTech Connect (OSTI)

    Duval, B. P. [Centre de Recherches en Physique des Plasmas, EPFL, Lausanne (Switzerland)

    2012-05-25T23:59:59.000Z

    For fusion, obtaining reliable measurements of basic plasma parameters like ion and electron densities and temperatures is a primary goal. For theory, measurements are needed as a function of time and space to understand plasma transport and confinement with the ultimate goal of achieving economic nuclear fusion power. Electron profile measurements and plasma spectroscopy for the plasma ions are introduced. With the advent of Neutral Beam auxiliary plasma heating, Charge Exchange Recombination Spectroscopy provides accurate and time resolved measurements of the ions in large volume fusion devices. In acknowledgement of Nicol Peacock's role in the development of these techniques, still at the forefront of plasma fusion research, this paper describes the evolution of this diagnostic method.

  1. Distinguishing quantum and classical transport through nanostructures

    E-Print Network [OSTI]

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

    2010-08-23T23:59:59.000Z

    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.

  2. Parity Breaking Transport in Lifshitz Hydrodynamics

    E-Print Network [OSTI]

    Carlos Hoyos; Adiel Meyer; Yaron Oz

    2015-05-12T23:59:59.000Z

    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.

  3. Transportation Security | ornl.gov

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

    Transportation Security SHARE Global Threat Reduction Initiative Transportation Security Cooperation Secure Transport Operations (STOP) Box Security of radioactive material while...

  4. 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

    2014-10-01T23:59:59.000Z

    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 statemore »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.« less

  5. 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)

    2014-10-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Samuel L Smith; Alex W Chin

    2014-06-04T23:59:59.000Z

    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.

  7. Flexible cobalt-phthalocyanine thin films with high charge carrier mobility

    SciTech Connect (OSTI)

    Singh, Ajay [Technical Physics Division, Bhabha Atomic Research Center, Mumbai 400 085 (India); Universite Paris Diderot, Sorbonne Paris Cite, ITODYS, UMR 7086, CNRS F-75013 Paris (France); Kumar, Arvind; Kumar, Ashwini; Samanta, Soumen; Debnath, Anil K.; Jha, Purushottam; Prasad, Rajeshwar; Aswal, Dinesh K.; Gupta, Shiv K. [Technical Physics Division, Bhabha Atomic Research Center, Mumbai 400 085 (India); Salmi, Zakaria; Nowak, Sophie; Chehimi, Mohamed M. [Universite Paris Diderot, Sorbonne Paris Cite, ITODYS, UMR 7086, CNRS F-75013 Paris (France)

    2012-11-26T23:59:59.000Z

    The structural and charge transport characteristics of cobalt phthalocyanine (CoPc) films deposited on flexible bi-axially oriented polyethylene terephthalate (BOPET) substrates are investigated. CoPc films exhibited a preferential (200) orientation with charge carrier mobility of {approx}118 cm{sup 2} V{sup -1} s{sup -1} (at 300 K). These films exhibited a reversible resistance changes upon bending them to different radius of curvature. The charge transport in CoPc films is governed by a bias dependent crossover from ohmic (J-V) to trap-free space-charge limited conduction (J-V{sup 2}). These results demonstrate that CoPc films on flexible BOPET having high mobility and high mechanical flexibility are a potential candidate for flexible electronic devices.

  8. Charge Separation for Muon Collider Cooling

    SciTech Connect (OSTI)

    Palmer, R.B.; Fernow; R.C.

    2011-03-28T23:59:59.000Z

    Most schemes for six dimensional muon ionization cooling work for only one sign. It is then necessary to have charge separation prior to that cooling. Schemes of charge separation using bent solenoids are described, and their simulated performances reported. It is found that for efficient separation, it should take place at somewhat higher momenta than commonly used for the cooling. Charge separation using bent solenoids can be effective if carefully designed. Bent solenoids can generate dispersion from 'momentum drift', but can spoil emittance from 'amplitude drift'. Abrupt entry into a bent solenoid causes emittance growth, but matching using integral {lambda} lengths, or Norem's method, corrects this problem. Reverse bending removes the dispersion and reduces 'amplitude drift', but only if there is no rf until after all bending. The main problem is bunch lengthening and distortion from the long transports without rf. At 230 MeV/c, even with a higher field of 3 T, non-linearities increase the 6D emittance by 117% and give 13% loss, which is not acceptable. Raising the momentum from 230 to 300 MeV gives a 6D emittance growth of 38% and the loss 5%, which may be acceptable. Raising the momentum further to 400 MeV/c gives very good results: 6D growth of 24% and 2.5% loss. Further optimization should include the acceleration to the higher momenta prior to the separation, and the higher momentum cooling immediately after it. The longitudinal phase space prior to the separation should be rotated to minimize the total bunch lengthening.

  9. "Educating transportation professionals."

    E-Print Network [OSTI]

    Acton, Scott

    "Educating transportation professionals." Michael Demetsky Henry L. Kinnier Professor mjd of Virginia Charlottesville, VA 434.924.7464 Transportation Engineering & Management Research Our group works closely with the Virginia Center for Transportation Innovation and Research (VCTIR), located

  10. Method of identifying defective particle coatings

    DOE Patents [OSTI]

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

    1986-01-01T23:59:59.000Z

    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.

  11. Capacitive charging system for high power battery charging

    SciTech Connect (OSTI)

    NONE

    1998-12-31T23:59:59.000Z

    This document describes a project to design, build, demonstrate, and document a Level 3 capacitive charging system, and it will be based on the existing PEZIC prototype capacitive coupler. The capacitive coupler will be designed to transfer power at a maximum of 600 kW, and it will transfer power by electric fields. The power electronics will transfer power at 100 kW. The coupler will be designed to function with future increases in the power electronics output power and increases in the amp/hours capacity of sealed batteries. Battery charging algorithms will be programmed into the control electronics. The finished product will be a programmable battery charging system capable of transferring 100 kW via a capacitive coupler. The coupler will have a low power loss of less than 25 watts when transferring 240 kW (400 amps). This system will increase the energy efficiency of high power battery charging, and it will enhance mobility by reducing coupler failures. The system will be completely documented. An important deliverable of this project is information. The information will be distributed to the Army`s TACOM-TARDEC`s Advanced Concept Group, and it will be distributed to commercial organizations by the Society of Automotive Engineers. The information will be valuable for product research, development, and specification. The capacitive charging system produced in this project will be of commercial value for future electric vehicles. The coupler will be designed to rapid charge batteries that have a capacity of several thousand amp/hours at hundreds of volts. The charging system built here will rapid charge batteries with several hundred amp/hours capacity, depending on the charging voltage.

  12. Adiabatic charge pumping in open quantum systems J.E. Avron(a)

    E-Print Network [OSTI]

    Adiabatic charge pumping in open quantum systems J.E. Avron(a) , A. Elgart(b) , G.M. Graf(c) , L for charge transport in quantum pumps connected to a number of external leads. It is proved that under rather the pump is given by a formula of B¨uttiker, Pr^etre, and Thomas, relating it to the frozen S

  13. Sustainability and Transport

    E-Print Network [OSTI]

    Gilbert, Richard

    2006-01-01T23:59:59.000Z

    2005. Integrating Sustainability into the Trans- portationTHOUGHT PIECE Sustainability and Transport by Richardof the concept of sustainability to transport planning. In

  14. Chapter 12 Transportation

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

    2-1 November 2012 Words in bold and acronyms are defined in Chapter 32, Glossary and Acronyms. Chapter 12 Transportation This chapter describes existing transportation resources in...

  15. Transportation | Argonne National Laboratory

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

    Transportation From modeling and simulation programs to advanced electric powertrains, engines, biofuels, lubricants, and batteries, Argonne's transportation research is vital to...

  16. 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...

  17. Computer programs for eddy-current defect studies

    SciTech Connect (OSTI)

    Pate, J. R.; Dodd, C. V. [Oak Ridge National Lab., TN (USA)

    1990-06-01T23:59:59.000Z

    Several computer programs to aid in the design of eddy-current tests and probes have been written. The programs, written in Fortran, deal in various ways with the response to defects exhibited by four types of probes: the pancake probe, the reflection probe, the circumferential boreside probe, and the circumferential encircling probe. Programs are included which calculate the impedance or voltage change in a coil due to a defect, which calculate and plot the defect sensitivity factor of a coil, and which invert calculated or experimental readings to obtain the size of a defect. The theory upon which the programs are based is the Burrows point defect theory, and thus the calculations of the programs will be more accurate for small defects. 6 refs., 21 figs.

  18. Physisorption of molecular hydrogen on carbon nanotube with vacant defects

    SciTech Connect (OSTI)

    Sun, Gang; Shen, Huaze; Wang, Enge; Xu, Limei, E-mail: limei.xu@pku.edu.cn [International Center for Quantum Materials and School of Physics, Peking University, Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter, Beijing (China); Tangpanitanon, Jirawat [University of Cambridge, Cambridge, Cambridgeshire CB2 1TP (United Kingdom); Wen, Bo [International Center for Quantum Materials and School of Physics, Peking University, Beijing 100871 (China); Beijing Computational Science Research Center, Heqing Street, Haidian District, Beijing 100084 (China); Xue, Jianming [State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China); Center for Applied Physics and Technology, Peking University, Beijing 100871 (China)

    2014-05-28T23:59:59.000Z

    Physisorption of molecular hydrogen on single-walled carbon nanotubes (SWCNTs) is important for its engineering applications and hydrogen energy storage. Using molecular dynamics simulation, we study the physisorption of molecular hydrogen on a SWCNT with a vacant defect, focusing on the effect of the vacant defect size and external parameters such as temperature and pressure. We find that hydrogen can be physisorbed inside a SWCNT through a vacant defect when the defect size is above a threshold. By controlling the size of the defects, we are able to extract hydrogen molecules from a gas mixture and store them inside the SWCNT. We also find that external parameters, such as low temperature and high pressure, enhance the physisorption of hydrogen molecules inside the SWCNT. In addition, the storage efficiency can be improved by introducing more defects, i.e., reducing the number of carbon atoms on the SWCNT.

  19. Charge-pump voltage converter

    DOE Patents [OSTI]

    Brainard, John P. (Albuquerque, NM); Christenson, Todd R. (Albuquerque, NM)

    2009-11-03T23:59:59.000Z

    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.

  20. Space charge modeling in electron-beam irradiated polyethylene: Fitting model and experiments

    SciTech Connect (OSTI)

    Le Roy, S.; Laurent, C.; Teyssedre, G. [Universite de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, F-31062 Toulouse cedex 9 (France); CNRS, LAPLACE, F-31062 Toulouse (France); Baudoin, F.; Griseri, V. [Universite de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, F-31062 Toulouse cedex 9 (France)

    2012-07-15T23:59:59.000Z

    A numerical model for describing charge accumulation in electron-beam irradiated low density polyethylene has been put forward recently. It encompasses the generation of positive and negative charges due to impinging electrons and their transport in the insulation. However, the model was not optimized to fit all the data available regarding space charge dynamics obtained using up-to-date pulsed electro-acoustic techniques. In the present approach, model outputs are compared with experimental space charge distribution obtained during irradiation and post-irradiation, the irradiated samples being in short circuit conditions or with the irradiated surface at a floating potential. A unique set of parameters have been used for all the simulations, and it encompasses the transport parameters already optimized for charge transport in polyethylene under an external electric field. The model evolution in itself consists in describing the recombination between positive and negative charges according to the Langevin formula, which is physically more accurate than the previous description and has the advantage of reducing the number of adjustable parameters of the model. This also provides a better description of the experimental behavior underlining the importance of recombination processes in irradiated materials.

  1. Quantification of the solid-state charge mobility in a model radical polymer

    SciTech Connect (OSTI)

    Baradwaj, Aditya G.; Rostro, Lizbeth; Boudouris, Bryan W., E-mail: boudouris@purdue.edu [School of Chemical Engineering, Purdue University, 480 Stadium Mall Drive, West Lafayette, Indiana 47907 (United States); Alam, Muhammad A. [School of Electrical and Computer Engineering, Purdue University, 475 Northwestern Avenue, West Lafayette, Indiana 47907 (United States)

    2014-05-26T23:59:59.000Z

    We establish that an oft-used radical polymer, poly(2,2,6,6-tetramethylpiperidinyloxy methacrylate) (PTMA), has a solid-state hole mobility value on the order of 10{sup ?4} cm{sup 2} V{sup ?1} s{sup ?1} in a space charge-limited device geometry. Despite being completely amorphous and lacking any ?-conjugation, these results demonstrate that the hole mobility of PTMA is comparable to many well-studied conjugated polymers [e.g., poly(3-hexylthiophene)]. Furthermore, we show that the space charge-limited charge carrier mobility of these macromolecules is only a weak function of temperature, in contrast to many thermally-activated models of charge transport in polymeric materials. This key result demonstrates that the charge transport in radical polymers is inherently different than that in semicrystalline, conjugated polymers. These results establish the mechanism of solid-state charge transport in radical polymers and provide macromolecular design principles for this emerging class of organic electronic materials.

  2. Simple intrinsic defects in GaAs : numerical supplement.

    SciTech Connect (OSTI)

    Schultz, Peter Andrew

    2012-04-01T23:59:59.000Z

    This Report presents numerical tables summarizing properties of intrinsic defects in gallium arsenide, GaAs, as computed by density functional theory. This Report serves as a numerical supplement to the results published in: P.A. Schultz and O.A. von Lilienfeld, 'Simple intrinsic defects in GaAs', Modelling Simul. Mater. Sci Eng., Vol. 17, 084007 (2009), and intended for use as reference tables for a defect physics package in device models. The numerical results for density functional theory calculations of properties of simple intrinsic defects in gallium arsenide are presented.

  3. Irradiation-induced defect clustering and amorphization in silicon...

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

    guidance on experimental approaches to reveal the onset of these processes. Citation: Weber WJ, and F Gao.2010."Irradiation-induced defect clustering and amorphization in silicon...

  4. The case against scaling defect models of cosmic structure formation

    E-Print Network [OSTI]

    Andreas Albrecht; Richard A. Battye; James Robinson

    1997-07-11T23:59:59.000Z

    We calculate predictions from defect models of structure formation for both the matter and Cosmic Microwave Background (CMB) over all observable scales. Our results point to a serious problem reconciling the observed large-scale galaxy distribution with the COBE normalization, a result which is robust for a wide range of defect parameters. We conclude that standard scaling defect models are in conflict with the data, and show how attempts to resolve the problem by considering non-scaling defects would require radical departures from the standard scaling picture.

  5. Evolution equation of moving defects: dislocations and inclusions

    E-Print Network [OSTI]

    Markenscoff, Xanthippi

    2010-01-01T23:59:59.000Z

    9483-8 ORIGINAL PAPER Evolution equation of moving defects:Springerlink.com Abstract Evolution equations, or equationsof dissipation, and the evolution equation for a plane

  6. Pipe inspection method gives 3D view of OCTG defects

    SciTech Connect (OSTI)

    Kahil, J. (Baker Hughes Tubular Services, Houston, TX (US))

    1990-07-01T23:59:59.000Z

    A new technique for the nondestructive testing of tubulars is presented. It locates small or oblique defects that are currently going undetected.

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

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

    theoretical capabilities. We are using deep-level optical spectroscopy to quantify defect energy levels and densities. Advanced density functional theory is being used to predict...

  8. annealing radiation defects: Topics by E-print Network

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

    is also investigated. Ionel Lazanu; Sorina Lazanu 2002-08-07 6 Radiation Damage in Silicon -Defect Analysis and Detector Properties - Physics Websites Summary:...

  9. The Energy of Charged Matter

    E-Print Network [OSTI]

    Jan Philip Solovej

    2004-06-07T23:59:59.000Z

    In this talk I will discuss some of the techniques that have been developed over the past 35 years to estimate the energy of charged matter. These techniques have been used to solve stability of (fermionic) matter in different contexts, and to control the instability of charged bosonic matter. The final goal will be to indicate how these techniques with certain improvements can be used to prove Dyson's 1967 conjecture for the energy of a charged Bose gas--the sharp $N^{7/5}$ law.

  10. Robust optimization based EV charging

    E-Print Network [OSTI]

    2015-03-04T23:59:59.000Z

    I. INTRODUC TION. The new paradigm of holistic transportation and power ... and control strategies have been proposed in the literature to capture the potential ...

  11. Efficient wireless charging with gallium nitride FETs

    E-Print Network [OSTI]

    Yeh, Theresa (Theresa I.)

    2014-01-01T23:59:59.000Z

    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 ...

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

    SciTech Connect (OSTI)

    Wakita, Masaki; Suzuki, Kei; Shinozuka, Yuzo [Faculty of Systems Engineering, Wakayama University, 930 Sakaedani, Wakayama 640-8510 (Japan)

    2014-02-21T23:59:59.000Z

    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.

  13. 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

    2010-08-28T23:59:59.000Z

    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.

  14. Parallel Transport of Electrons in Graphene Parallels Gravity

    E-Print Network [OSTI]

    Andrej Mesaros; Darius Sadri; Jan Zaanen

    2009-09-15T23:59:59.000Z

    Geometrically a crystal containing dislocations and disclinations can be envisaged as a `fixed frame' Cartan--Einstein space-time carrying torsion and curvature, respectively. We demonstrate that electrons in defected graphene are transported in the same way as fundamental Dirac fermions in a non-trivial 2+1 dimensional space-time, with the proviso that the graphene electrons remember the lattice constant through the valley quantum numbers. The extra `valley holonomy' corresponds to modified Euclidean symmetry generators.

  15. Turbo-Charged Lighting Design

    E-Print Network [OSTI]

    Clark, W. H. II

    TURBO-CHARGED LIGHTING DESIGN William H. Clark II Design Engineer O'Connell Robertson & Assoc Austin/ Texas ABSTRACT The task of the lighting designer has become very complex, involving thousands of choices for fixture types and hundreds...

  16. Premix charge, compression ignition combustion system optimization...

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

    Premix charge, compression ignition combustion system optimization Premix charge, compression ignition combustion system optimization Presentation given at DEER 2006, August 20-24,...

  17. Structure, Charge Distribution, and Electron Hopping Dynamics...

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

    Charge Distribution, and Electron Hopping Dynamics in Magnetite (Fe3O4) (100) Surfaces from First Principles. Structure, Charge Distribution, and Electron Hopping Dynamics in...

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

    Energy Savers [EERE]

    Charging Equipment (EVSE) Testing Data Vehicle Technologies Office: AVTA - Electric Vehicle Charging Equipment (EVSE) Testing Data Electric vehicle chargers (otherwise known as...

  19. EV Everywhere Grand Challenge - Charging Infrastructure Enabling...

    Office of Environmental Management (EM)

    Charging Infrastructure Enabling Flexible EV Design EV Everywhere Grand Challenge - Charging Infrastructure Enabling Flexible EV Design Presentation given at the EV Everywhere...

  20. Multi-modal Transportation > Highway Transportation > Trucking > Railroad transportation > Public transit > Rural transportation > Rural transit > Freight pipeline transportation > Airport planning and development > Airport maintenance > Bicycle and pedes

    E-Print Network [OSTI]

    Multi-modal Transportation > Highway Transportation > Trucking > Railroad transportation > Public transit > Rural transportation > Rural transit > Freight pipeline transportation > Airport planning and development > Airport maintenance > Bicycle and pedestrian > Ports and waterways >>> Transportation operat

  1. Multi-modal Transportation > Highway Transportation > Trucking > Railroad transportation > Public transit > Rural transportation > Rural transit > Freig pipeline transportation > Airport planning and development > Airport maintenance > Bicycle and pedestr

    E-Print Network [OSTI]

    Multi-modal Transportation > Highway Transportation > Trucking > Railroad transportation > Public transit > Rural transportation > Rural transit > Freig pipeline transportation > Airport planning and development > Airport maintenance > Bicycle and pedestrian > Ports and waterways >>> Transportation ope

  2. Theory of DNA translocation through narrow ion channels and nanopores with charged walls

    E-Print Network [OSTI]

    Tao Hu; B. I. Shklovskii

    2008-06-20T23:59:59.000Z

    Translocation of a single stranded DNA through genetically engineered $\\alpha$-hemolysin channels with positively charged walls is studied. It is predicted that transport properties of such channels are dramatically different from neutral wild type $\\alpha$-hemolysin channel. We assume that the wall charges compensate the fraction $x$ of the bare charge $q_{b}$ of the DNA piece residing in the channel. Our prediction are as follows (i) At small concentration of salt the blocked ion current decreases with $x$. (ii) The effective charge $q$ of DNA piece, which is very small at $x = 0$ (neutral channel) grows with $x$ and at $x=1$ reaches $q_{b}$. (iii) The rate of DNA capture by the channel exponentially grows with $x$. Our theory is also applicable to translocation of a double stranded DNA in narrow solid state nanopores with positively charged walls.

  3. Graduate Certificate in Transportation

    E-Print Network [OSTI]

    Bertini, Robert L.

    Graduate Certificate in Transportation Nohad A. Toulan School of Urban Studies and Planning of Engineering and Computer Science integrated transportation systems. The Graduate Certificate in Transportation their capabilities. Students in the program can choose among a wide range of relevant courses in transportation

  4. TRANSPORTATION Annual Report

    E-Print Network [OSTI]

    Minnesota, University of

    2003 CENTER FOR TRANSPORTATION STUDIES Annual Report #12;Center for Transportation Studies University of Minnesota 200 Transportation and Safety Building 511 Washington Avenue S.E. Minneapolis, MN publication is a report of transportation research, education, and outreach activities for the period July

  5. Jet Charge at the LHC

    E-Print Network [OSTI]

    David Krohn; Tongyan Lin; Matthew D. Schwartz; Wouter J. Waalewijn

    2013-06-14T23:59:59.000Z

    Knowing the charge of the parton initiating a light-quark jet could be extremely useful both for testing aspects of the Standard Model and for characterizing potential beyond-the-Standard-Model signals. We show that despite the complications of hadronization and out-of-jet radiation such as pile-up, a weighted sum of the charges of a jet's constituents can be used at the LHC to distinguish among jets with different charges. Potential applications include measuring electroweak quantum numbers of hadronically decaying resonances or supersymmetric particles, as well as Standard Model tests, such as jet charge in dijet events or in hadronically-decaying W bosons in t-tbar events. We develop a systematically improvable method to calculate moments of these charge distributions by combining multi-hadron fragmentation functions with perturbative jet functions and pertubative evolution equations. We show that the dependence on energy and jet size for the average and width of the jet charge can be calculated despite the large experimental uncertainty on fragmentation functions. These calculations can provide a validation tool for data independent of Monte-Carlo fragmentation models.

  6. Minnesota's Transportation Economic Development (TED)

    E-Print Network [OSTI]

    Minnesota, University of

    Minnesota's Transportation Economic Development (TED) Pilot Program Center for Transportation Studies Transportation Research Conference May 24-25, 2011 #12;Transportation Role in Economic Development · Carefully targeted transportation infrastructure improvements will: ­ Stimulate new economic development

  7. 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

  8. Electric Field-Induced Skyrmion Crystals via Charged Monopoles in Insulating Helimagets

    E-Print Network [OSTI]

    Haruki Watanabe; Ashvin Vishwanath

    2014-10-08T23:59:59.000Z

    Electrons propagating in a magnetically ordered medium experience an additional gauge field associated with the Berry phase of their spin following the local magnetic texture. In contrast to the usual electromagnetic field, this gauge field admits monopole excitations, corresponding to hedgehog defects of the magnetic order. In an insulator, these hedgehogs carry a well-defined electric charge allowing for them to be controlled by electric fields. One particularly robust mechanism that contributes to the charge is the orbital magnetoelectric effect, captured by a $\\theta$ angle, which leads to a charge of $e\\theta/2\\pi$ on hedgehogs. This is a direct consequence of the Witten effect for magnetic monopoles in a $\\theta$ medium. A physical consequence is that external electric fields can induce skyrmion crystal phases in insulating helimagnets.

  9. Spectroscopy of Charge Carriers and Traps in Field-Doped Single Crystal Organic Semiconductors

    SciTech Connect (OSTI)

    Zhu, Xiaoyang

    2014-12-10T23:59:59.000Z

    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?

  10. Simple intrinsic defects in InAs : numerical predictions.

    SciTech Connect (OSTI)

    Schultz, Peter Andrew

    2013-03-01T23:59:59.000Z

    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.

  11. Actinic characterization of EUV bump-type phase defects

    SciTech Connect (OSTI)

    Goldberg, Kenneth A.; Mochi, Iacopo; Liang, Ted

    2011-01-10T23:59:59.000Z

    Despite tremendous progress and learning with EUV lithography, quantitative experimental information about the severity of point-like phase defects remains in short supply. We present a study of measured, EUV aerial images from a series of well-characterized, open-field, bump-type programmed phase defects, created on a substrate before multilayer deposition.

  12. CHARACTERIZATION OF VIBRATIONINDUCED IMAGE DEFECTS IN INPUT SCANNERS

    E-Print Network [OSTI]

    Wolberg, George

    ) by dynamic errors of gears, timing bets, and motors, and indirectly by structural vibrations induced by gearsCHARACTERIZATION OF VIBRATION­INDUCED IMAGE DEFECTS IN INPUT SCANNERS Robert P. Loce George Wolberg. Keywords: image defects, digital documents, scanned documents, vibrations, motion quality 1. INTRODUCTION

  13. Built-In Self Test (BIST) for Realistic Delay Defects

    E-Print Network [OSTI]

    Tamilarasan, Karthik Prabhu

    2012-02-14T23:59:59.000Z

    with the insertion of test points, BIST is able to achieve high coverage of stuck-at and transition faults. The quality of BIST patterns on small delay defects is an open question. In this work we analyze the application of BIST to small delay defects using resistive...

  14. Defect in lung growth* Comparative study of three diagnostic criteria.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Defect in lung growth* Comparative study of three diagnostic criteria. P. DECHELOTTE, A. LABBE, O and fetuses (49 pathological cases and 25 controls) to detect defects in lung growth. In each case lung disease. RA count is low in lung hypoplasia but is not an entirely reliable diagnostic criterion since

  15. Charging effect simulation model used in simulations of plasma etching of silicon

    SciTech Connect (OSTI)

    Ishchuk, Valentyn; Volland, Burkhard E.; Hauguth, Maik; Rangelow, Ivo W. [Department of Micro- and Nanoelectronic Systems, Ilmenau University of Technology, Ilmenau 98693 (Germany); Cooke, Mike [Oxford Instruments Plasma Technology, North End, Yatton, Bristol BS49 4AP (United Kingdom)

    2012-10-15T23:59:59.000Z

    Understanding the consequences of local surface charging on the evolving etching profile is a critical challenge in high density plasma etching. Deflection of the positively charged ions in locally varying electric fields can cause profile defects such as notching, bowing, and microtrenching. We have developed a numerical simulation model capturing the influence of the charging effect over the entire course of the etching process. The model is fully integrated into ViPER (Virtual Plasma Etch Reactor)-a full featured plasma processing simulation software developed at Ilmenau University of Technology. As a consequence, we show that local surface charge concurrently evolves with the feature profile to affect the final shape of the etched feature. Using gas chopping (sometimes called time-multiplexed) etch process for experimental validation of the simulation, we show that the model provides excellent fits to the experimental data and both, bowing and notching effects are captured-as long as the evolving profile and surface charge are simultaneously simulated. In addition, this new model explains that surface scallops, characteristic of gas chopping technique, are eroded and often absent in the final feature profile due to surface charging. The model is general and can be applied across many etching chemistries.

  16. 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)

    2007-03-21T23:59:59.000Z

    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.

  17. Disentangling defects and sound modes in disordered solids

    E-Print Network [OSTI]

    Sven Wijtmans; M. Lisa Manning

    2015-02-05T23:59:59.000Z

    We develop a new method to isolate localized defects from extended vibrational modes in disordered solids. This method augments particle interactions with an artificial potential that acts as a high-pass filter: it preserves small-scale structures while pushing extended vibrational modes to higher frequencies. The low-frequency modes that remain are "bare" defects; they are exponentially localized without the quadrupolar tails associated with elastic interactions. We identify a robust definition for the energy barrier associated with each defect, which is an important parameter in continuum models for plasticity. Surprisingly, we find that the energy barriers associated with "bare" defects are generally higher than those for defects decorated with elastic tails, suggesting that elastic interactions may help to constitutively activate particle rearrangements.

  18. 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

    2013-01-01T23:59:59.000Z

    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 ...

  19. Determination of Electrochemical Performance and Thermo-Mechanical-Chemical Stability of SOFCs from Defect Modeling

    SciTech Connect (OSTI)

    Eric Wachsman; Keith L. Duncan

    2006-09-30T23:59:59.000Z

    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.

  20. Phase stable RF transport system

    DOE Patents [OSTI]

    Curtin, Michael T. (Los Alamos, NM); Natter, Eckard F. (San Francisco, CA); Denney, Peter M. (Los Alamos, NM)

    1992-01-01T23:59:59.000Z

    An RF transport system delivers a phase-stable RF signal to a load, such as an RF cavity of a charged particle accelerator. A circuit generates a calibration signal at an odd multiple frequency of the RF signal where the calibration signal is superimposed with the RF signal on a common cable that connects the RF signal with the load. Signal isolating diplexers are located at both the RF signal source end and load end of the common cable to enable the calibration to be inserted and extracted from the cable signals without any affect on the RF signal. Any phase shift in the calibration signal during traverse of the common cable is then functionally related to the phase shift in the RF signal. The calibration phase shift is used to control a phase shifter for the RF signal to maintain a stable RF signal at the load.

  1. A non-isothermal PEM fuel cell model including two water transport mechanisms in the

    E-Print Network [OSTI]

    Münster, Westfälische Wilhelms-Universität

    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

  2. PHYSICAL REVIEW B 88, 195409 (2013) Effects of disorder and contacts on transport through graphene nanoribbons

    E-Print Network [OSTI]

    Fehske, Holger

    2013-01-01T23:59:59.000Z

    PHYSICAL REVIEW B 88, 195409 (2013) Effects of disorder and contacts on transport through graphene; published 12 November 2013) We study the transport of charge carriers through finite graphene structures samples beyond the Dirac-cone approximation. Particularly we investigate disordered nanoribbons, normal-conductor/graphene

  3. Non-intrusive measurement of particle charge: Electrostatic dry coal cleaning. Technical progress report No. 11, January 1, 1994--March 31, 1994

    SciTech Connect (OSTI)

    Not Available

    1994-06-01T23:59:59.000Z

    As has been previously reported, the charge measurement portion of this project has been broadened to include direct measurement techniques which yield an average particle charge per unit mass. These methods, which now include current measurements from the charging loop, an electrolytic collection solution and a Faraday cage have been employed to expand the charge measurement capabilities over those that were originally developed using the PDPA. The effects of gas velocity, humidity and temperature as well as particle size on charge was evaluated for different coals and silica. The charge accumulated on silica particles was linearly dependent on their velocity in the tribocharger for the velocities and mass loadings which were investigated. For coals, a linear increase in charge occurred over a more limited velocity range. Transport gas humidity had a much stronger effect on the charge established on silica particles than on coal particles.

  4. Final Technical Report for DE-SC0001878 [Theory and Simulation of Defects in Oxide Materials

    SciTech Connect (OSTI)

    Chelikowsky, James R. [University of Texas at Austin] [University of Texas at Austin

    2014-04-14T23:59:59.000Z

    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.

  5. Secure Transportation Management

    SciTech Connect (OSTI)

    Gibbs, P. W. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2014-10-15T23:59:59.000Z

    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.

  6. 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...

  7. Battery Electric Vehicle Driving and Charging Behavior Observed Early in The EV Project

    SciTech Connect (OSTI)

    John Smart; Stephen Schey

    2012-04-01T23:59:59.000Z

    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.

  8. Electrostatic wire stabilizing a charged particle beam

    DOE Patents [OSTI]

    Prono, D.S.; Caporaso, G.J.; Briggs, R.J.

    1983-03-21T23:59:59.000Z

    In combination with a charged particle beam generator and accelerator, apparatus and method are provided for stabilizing a beam of electrically charged particles. A guiding means, disposed within the particle beam, has an electric charge induced upon it by the charged particle beam. Because the sign of the electric charge on the guiding means and the sign of the particle beam are opposite, the particles are attracted toward and cluster around the guiding means to thereby stabilize the particle beam as it travels.

  9. Sacrificial Charge and Charge Injection! Evolution of Line Width!

    E-Print Network [OSTI]

    Grant, Catherine E.

    MeV). Anti-correlated with the solar cycle. Similar structures are seen in the energy scale due background" which depends on solar cycle and activity." XIS energy scale and line width as a function of cut increasing CTI, trailing charge and event/split thresholds Evolution of Energy Scale! · Radiation damage

  10. Charged particle mobility refrigerant analyzer

    DOE Patents [OSTI]

    Allman, S.L.; Chunghsuan Chen; Chen, F.C.

    1993-02-02T23:59:59.000Z

    A method for analyzing a gaseous electronegative species comprises the steps of providing an analysis chamber; providing an electric field of known potential within the analysis chamber; admitting into the analysis chamber a gaseous sample containing the gaseous electronegative species; providing a pulse of free electrons within the electric field so that the pulse of free electrons interacts with the gaseous electronegative species so that a swarm of electrically charged particles is produced within the electric field; and, measuring the mobility of the electrically charged particles within the electric field.

  11. Magnetic moment versus tensor charge

    E-Print Network [OSTI]

    M. Mekhfi

    2005-05-10T23:59:59.000Z

    We express the baryon magnetic moments in terms of the baryon tensor charges, considering the quarks as relativistic interacting objects. Once tensor charges get measured accurately, the formula for the baryon magnetic moment will serve to extract precise information on the quark anomalous magnetic moment, the quark effective mass and the ratio of the quark constituent mass to the quark effective mass. The analogous formula for the baryon electric dipole moment is of no great use as it gets eventually sizable contributions from various CP- violating sources not necessary associated to the quark electric dipole moment.

  12. Transportation Infrastructure and Sustainable Development

    E-Print Network [OSTI]

    Boarnet, Marlon G.

    2008-01-01T23:59:59.000Z

    A Better Forecasting Tool for Transportation Decision-making,” Mineta Transportation Institute, San Jose Stateat the 2008 meeting of the Transportation Research Board and

  13. Transportation Analysis | Clean Energy | ORNL

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

    Transportation Analysis SHARE Transportation Analysis Transportation Analysis efforts at Oak Ridge National Laboratory contribute to the efficient, safe, and free movement of...

  14. Adiabatic charge pumping in open quantum systems J.E. Avron (a) , A. Elgart (b) , G.M. Graf (c) , L. Sadun (d) , K. Schnee (e)

    E-Print Network [OSTI]

    Adiabatic charge pumping in open quantum systems J.E. Avron (a) , A. Elgart (b) , G.M. Graf (c) , L for charge transport in quantum pumps connected to a number of external leads. It is proved that under rather the pump is given by a formula of Buttiker, Pr^etre, and Thomas, relating it to the frozen S

  15. Adiabatic charge pumping in open quantum systems J.E. Avron (a) , A. Elgart (b) , G.M. Graf (c) , L. Sadun (d) , K. Schnee (e)

    E-Print Network [OSTI]

    Adiabatic charge pumping in open quantum systems J.E. Avron (a) , A. Elgart (b) , G.M. Graf (c) , L for charge transport in quantum pumps connected to a number of external leads. It is proved that under rather the pump is given by a formula of BË?uttiker, Prâ??etre, and Thomas, relating it to the frozen S

  16. Transportation Investment and

    E-Print Network [OSTI]

    Levinson, David M.

    Transportation Investment and Economic Development: Has the TIED turned? David Levinson University Transportation Investments was Historically Concomitant with Land and Economic Development #12;Canals Railways Surfaced Roads Crude Oil Pipelines Gas Pipelines Telegraph 1825 1985 Proportion of Maximum Extent Growth

  17. Transportation Management Research Collection /

    E-Print Network [OSTI]

    Handy, Todd C.

    , Peterbilt Motors, and General Electric. He was a national panel member of the American Arbitration, Noise and Environmental Pollution, Transportation Co-ordination and Consolidation, Transportation -- Docket 8613 1957 Civil Aeronautics Board ­ General passenger fare investigation -- Docket 8008 et al

  18. Packaging and Transportation Safety

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1995-09-27T23:59:59.000Z

    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)]

    1995-09-27T23:59:59.000Z

    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

  20. Packaging and Transportation Safety

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1996-10-02T23:59:59.000Z

    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.

  1. 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

  2. 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. ...

  3. Transportation Management Workshop: Proceedings

    SciTech Connect (OSTI)

    Not Available

    1993-10-01T23:59:59.000Z

    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.

  4. Point defect balance in epitaxial GaSb

    SciTech Connect (OSTI)

    Segercrantz, N., E-mail: natalie.segercrantz@aalto.fi; Slotte, J.; Makkonen, I.; Kujala, J.; Tuomisto, F. [Department of Applied Physics, Aalto University, P.O. Box 14100, FIN-00076 Aalto Espoo (Finland); Song, Y.; Wang, S. [Department of Microtechnology and Nanoscience, Chalmers University of Technology, 41296 Göteborg (Sweden); State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences 865 Changning Road, Shanghai 200050 (China)

    2014-08-25T23:59:59.000Z

    Positron annihilation spectroscopy in both conventional and coincidence Doppler broadening mode is used for studying the effect of growth conditions on the point defect balance in GaSb:Bi epitaxial layers grown by molecular beam epitaxy. Positron annihilation characteristics in GaSb are also calculated using density functional theory and compared to experimental results. We conclude that while the main positron trapping defect in bulk samples is the Ga antisite, the Ga vacancy is the most prominent trap in the samples grown by molecular beam epitaxy. The results suggest that the p–type conductivity is caused by different defects in GaSb grown with different methods.

  5. 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)

    2014-01-27T23:59:59.000Z

    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.

  6. Spin Transport in Semiconductor heterostructures

    SciTech Connect (OSTI)

    Domnita Catalina Marinescu

    2011-02-22T23:59:59.000Z

    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.

  7. 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

  8. Indianapolis Public Transportation Corporation

    SciTech Connect (OSTI)

    Not Available

    2004-12-01T23:59:59.000Z

    Fact sheet describes the National Renewable Energy Laboratory's evaluation of Indianapolis Public Transportation Corporation's (IndyGo's) hybrid electric buses.

  9. Lubbock Metropolitan Transportation Plan

    E-Print Network [OSTI]

    Lubbock Metropolitan Planning Organization

    2007-09-18T23:59:59.000Z

    for Users (SAFETEA-LU) and its predecessors, the Transportation Equity Act for the 21st Century (TEA-21) and the Intermodal Surface Transportation Efficiency Act (ISTEA) of 1991, specified the transportation systems on which certain federal funds can... in Chapter 5 ? Streets and Highways; Chapter 6 ? Public Transportation; Chapter 7 ? Bicycle and Pedestrian Plan; Chapter 8 ? Lubbock International Airport and Chapter 9 ? Railroads and Trucking. Federally funded transit projects were developed...

  10. Transportation and its Infrastructure

    E-Print Network [OSTI]

    2007-01-01T23:59:59.000Z

    subsidies on fossil transport fuels, subsidies on commutingC. , 2003: Subsidies that encourage fossil fuel use in

  11. Transportation Secure Data Center: Real-World Data for Transportation Planning and Land Use Analysis (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-01-01T23:59:59.000Z

    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.

  12. Transportation and its Infrastructure

    E-Print Network [OSTI]

    2007-01-01T23:59:59.000Z

    electrical energy if regenerative braking is available (seerecharged only by regenerative braking and engine charging,systems, store regenerative braking energy and to operate

  13. Northwestern University Transportation Center

    E-Print Network [OSTI]

    Bustamante, Fabián E.

    Northwestern University Transportation Center 2011 Business Advisory Committee NUTC #12;#12;I have the pleasure of presenting our Business Advisory Committee members--a distinguished group of transportation industry lead- ers who have partnered with the Transportation Center in advancing the state of knowledge

  14. PalladianDigest Transportation

    E-Print Network [OSTI]

    Farritor, Shane

    PalladianDigest CONNECT. EMPOWER. GROW. Tackling Transportation Challenges Nebraska has been a vital link in the nation's transportation system since the days when carts, wagons to University of Nebraska­Lincoln research. That's fine with UNL transportation researchers, said Larry Rilett

  15. TRANSPORTATION: THE POTENTIAL

    E-Print Network [OSTI]

    Minnesota, University of

    INTERMODAL TRANSPORTATION: THE POTENTIAL AND THE CHALLENGE A Summary Report 2003 #12;June 2003 To the Reader This report summarizes the second James L. Oberstar Forum on Transportation Policy and Technology. Over two days, we explored the chal- lenges and opportunities in intermodal transportation, addressing

  16. Louisiana Transportation Research Center

    E-Print Network [OSTI]

    Harms, Kyle E.

    Louisiana Transportation Research Center LTRC www.ltrc.lsu.edu 2012-13 ANNUALREPORT #12;The Louisiana Transportation Research Center (LTRC) is a research, technology transfer, and training center administered jointly by the Louisiana Department of Transportation and Development (DOTD) and Louisiana State

  17. 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 on a Saturday night, transportation is not an objective in and of itself, but a means to carry out the functions of daily living (i.e., it's a "derived good"). As a consequence, the transportation systems we build

  18. Rural Intelligent Transportation Systems

    E-Print Network [OSTI]

    Minnesota, University of

    Rural Intelligent Transportation Systems In a technical session at the 2011 NACE conference, Dennis Foderberg of SEH Inc. discussed intelligent transportation systems (ITS) developed by SEH in collaboration with Network Transportation Technologies, Inc. These systems address the problem of crashes on low-volume roads

  19. Charge confinement and Klein tunneling from doping graphene

    E-Print Network [OSTI]

    C. Popovici; O. Oliveira; W. de Paula; T. Frederico

    2012-02-14T23:59:59.000Z

    In the present work, we investigate how structural defects in graphene can change its transport properties. In particular, we show that breaking of the sublattice symmetry in a graphene monolayer overcomes the Klein effect, leading to confined states of massless Dirac fermions. Experimentally, this corresponds to chemical bonding of foreign atoms to carbon atoms, which attach themselves to preferential positions on one of the two sublattices. In addition, we consider the scattering off a tensor barrier, which describes the rotation of the honeycomb cells of a given region around an axis perpendicular to the graphene layer. We demonstrate that in this case the intervalley mixing between the Dirac points emerges, and that Klein tunneling occurs.

  20. Phonon-Assisted Ultrafast Charge Separation in a Realistic PCBM Aggregate

    E-Print Network [OSTI]

    Samuel L. Smith; Alex W. Chin

    2014-06-25T23:59:59.000Z

    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.

  1. RETHINKING STANDBY & FIXED COST CHARGES

    E-Print Network [OSTI]

    intended to recover a more significant share of fixed costs solely from solar PV customer- generators rooftop solar PV development at limited to no cost to taxpayers and non-solar utility customers. StandbyPage | i RETHINKING STANDBY & FIXED COST CHARGES: REGULATORY & RATE DESIGN PATHWAYS TO DEEPER SOLAR

  2. RELIABILITY OF CAPACITOR CHARGING UNITS

    E-Print Network [OSTI]

    Sprott, Julien Clinton

    experience little change while those using the electronic cutoff would drift due to ageing components and changing parameters. The first few shots using the electronic cutoff were less reliable than subsequentRELIABILITY OF CAPACITOR CHARGING UNITS Clint Sprott July 30, 1965 University of Wisconsin

  3. Defect reaction network in Si-doped InP : numerical predictions.

    SciTech Connect (OSTI)

    Schultz, Peter Andrew

    2013-10-01T23:59:59.000Z

    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.

  4. Angular neutron transport investigation in the HZETRN free-space ion and nucleon transport and shielding computer program

    SciTech Connect (OSTI)

    Singleterry, R.C. Jr. [Argonne National Lab. - West, Idaho Falls, ID (United States); Wilson, J.W. [National Aeronautics and Space Administration, Hampton, VA (United States). Langley Research Center

    1997-05-01T23:59:59.000Z

    Extension of the high charge and energy (HZE) transport computer program HZETRN for angular transport of neutrons is considered. For this paper, only light ion transport, He{sup 4} and lighter, will be analyzed using a pure solar proton source. The angular transport calculator is the ANISN/PC program which is being controlled by the HZETRN program. The neutron flux values are compared for straight-ahead transport and angular transport in one dimension. The shield material is aluminum and the target material is water. The thickness of these materials is varied; however, only the largest model calculated is reported which is 50 gm/cm{sup 2} of aluminum and 100 gm/cm{sup 2} of water. The flux from the ANISN/PC calculation is about two orders of magnitude lower than the flux from HZETRN for very low energy neutrons. It is only a magnitude lower for the neutrons in the 10 to 20 MeV range in the aluminum and two orders lower in the water. The major reason for this difference is in the transport modes: straight-ahead versus angular. The angular treatment allows a longer path length than the straight-ahead approximation. Another reason is the different cross section sets used by the ANISN/PC-BUGLE-80 mode and the HZETRN mode. The next step is to investigate further the differences between the two codes and isolate the differences to just the angular versus straight-ahead transport mode. Then, create a better coupling between the angular neutron transport and the charged particle transport.

  5. Transportation YOU 2013 DC Youth Summit WTS Transportation YOU

    E-Print Network [OSTI]

    Minnesota, University of

    Transportation YOU 2013 DC Youth Summit WTS Transportation YOU CTS Research Conference May 21, 2014 Lisa Rasmussen, WTS / Kimley-Horn and Associates, Inc #12;Transportation YOU 2013 DC Youth SummitTransportation YOU 2013 DC Youth Summit Agenda What is Transportation YOU? Transportation YOU ­ WTS Local Chapter

  6. Center for Intermodal Transportation Safety

    E-Print Network [OSTI]

    Fernandez, Eduardo

    Center for Intermodal Transportation Safety and Security Panagiotis Scarlatos, Ph.D., Director Transportation Safety and Security #12;Center for Intermodal Transportation Safety and Security Partners #12 evacuations · Tracking systems for hazardous materials Center for Intermodal Transportation Safety

  7. Public Works Transportation Infrastructure Study

    E-Print Network [OSTI]

    Minnesota, University of

    Public Works Transportation Infrastructure Study Minneapolis City of Lakes Minneapolis Public Works Transportation Infrastructure Study #12;Public Works Transportation Infrastructure Study Minneapolis City Works Transportation Infrastructure Study Minneapolis City of Lakes Background: · Currently, funding

  8. Topological defect motifs in two-dimensional Coulomb clusters

    E-Print Network [OSTI]

    Radzvilavi?ius, A; 10.1088/0953-8984/23/38/385301

    2012-01-01T23:59:59.000Z

    The most energetically favourable arrangement of low-density electrons in an infinite two-dimensional plane is the ordered triangular Wigner lattice. However, in most instances of contemporary interest one deals instead with finite clusters of strongly interacting particles localized in potential traps, for example, in complex plasmas. In the current contribution we study distribution of topological defects in two-dimensional Coulomb clusters with parabolic lateral confinement. The minima hopping algorithm based on molecular dynamics is used to efficiently locate the ground- and low-energy metastable states, and their structure is analyzed by means of the Delaunay triangulation. The size, structure and distribution of geometry-induced lattice imperfections strongly depends on the system size and the energetic state. Besides isolated disclinations and dislocations, classification of defect motifs includes defect compounds --- grain boundaries, rosette defects, vacancies and interstitial particles. Proliferatio...

  9. Design and process solutions for decreasing vendor defects

    E-Print Network [OSTI]

    Joyce, Michael (Michael Sagar)

    2013-01-01T23:59:59.000Z

    Why do some new initiatives fail while others succeed? This thesis attempts to answer this complex question by investigating the failure of a defect tracking initiative at Amazon and examining how a reintroduction of the ...

  10. Wave propagation in periodic lattices with defects of smaller dimension

    E-Print Network [OSTI]

    A. A. Kutsenko

    2013-05-20T23:59:59.000Z

    The procedure of evaluating of the spectrum for discrete periodic operators perturbed by operators of smaller dimensions is obtained. This result allows to obtain propagative, guided, localised spectra for different kind of physical operators on graphs with defects.

  11. Defect specific maintenance of SG tubes -- How safe is it?

    SciTech Connect (OSTI)

    Cizelj, L.; Mavko, B.; Dvorsek, T. [Jozef Stefan Institute, Ljubljana (Slovenia)

    1997-02-01T23:59:59.000Z

    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.

  12. Role of defects in III-nitride based electronics

    SciTech Connect (OSTI)

    HAN,JUNG; MYERS JR.,SAMUEL M.; FOLLSTAEDT,DAVID M.; WRIGHT,ALAN F.; CRAWFORD,MARY H.; LEE,STEPHEN R.; SEAGER,CARLETON H.; SHUL,RANDY J.; BACA,ALBERT G.

    2000-01-01T23:59:59.000Z

    The LDRD entitled ``Role of Defects in III-Nitride Based Devices'' is aimed to place Sandia National Laboratory at the forefront of the field of GaN materials and devices by establishing a scientific foundation in areas such as material growth, defect characterization/modeling, and processing (metalization and etching) chemistry. In this SAND report the authors summarize their studies such as (1) the MOCVD growth and doping of GaN and AlGaN, (2) the characterization and modeling of hydrogen in GaN, including its bonding, diffusion, and activation behaviors, (3) the calculation of energetic of various defects including planar stacking faults, threading dislocations, and point defects in GaN, and (4) dry etching (plasma etching) of GaN (n- and p-types) and AlGaN. The result of the first AlGaN/GaN heterojunction bipolar transistor is also presented.

  13. Method and apparatus for inspecting reflection masks for defects

    DOE Patents [OSTI]

    Bokor, Jeffrey (Oakland, CA); Lin, Yun (Berkeley, CA)

    2003-04-29T23:59:59.000Z

    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.

  14. Liability for Defective Documentation FloridaInstitute of Technology

    E-Print Network [OSTI]

    Liability for Defective Documentation Cem Kaner FloridaInstitute of Technology 150 West University behind its claims. False claims in documentation might subject the manufacturer to liability for breach Engineering]: Distribution, Maintenance and Enhancement ­ documentation. General Terms Documentation, Human

  15. 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...

  16. Defects and impurities in graphene-like materials

    E-Print Network [OSTI]

    Terrones, Mauricio

    Graphene-like materials could be used in the fabrication of electronic and optoelectronic devices, gas sensors, biosensors, and batteries for energy storage. Since it is almost impossible to work with defect-free or ...

  17. Built-In Self Test (BIST) for Realistic Delay Defects 

    E-Print Network [OSTI]

    Tamilarasan, Karthik Prabhu

    2012-02-14T23:59:59.000Z

    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 ...

  18. Quality improvement and control based on defect reduction

    E-Print Network [OSTI]

    Dai, Qi, M. Eng. Massachusetts Institute of Technology

    2010-01-01T23:59:59.000Z

    This thesis addresses the quality improvement in a printing process at a food packaging company now experiencing hundreds of printing defects. Methodologies of Define, Measure, Analyze, Improve, and Control (DMAIC), and ...

  19. Modeling rough energy landscapes in defected condensed matter

    E-Print Network [OSTI]

    Monasterio Velásquez, Paul Rene

    2010-01-01T23:59:59.000Z

    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 ...

  20. Role of fluctuations and defects in select condensed matter problems

    E-Print Network [OSTI]

    Pressé, Steve, 1981-

    2008-01-01T23:59:59.000Z

    Defects and fluctuations dominate both static and dynamical properties of systems in the condensed phase. In this work, we focus on three such examples. Firstly, we model the effect of proton fluctuations on the rate of ...

  1. Spin properties of very shallow nitrogen vacancy defects in diamond

    E-Print Network [OSTI]

    Ofori-Okai, Benjamin Kwasi

    We investigate spin and optical properties of individual nitrogen vacancy centers located within 1–10 nm from the diamond surface. We observe stable defects with a characteristic optically detected magnetic-resonance ...

  2. Sandia National Laboratories: Research Challenge 4: Defect-Carrier...

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

    edge. Note that the density is much higher in the rightmost QW1 closest to the n-type GaN region. Our study of defects involves unique experimental and theoretical capabilities....

  3. Heavy and Overweight Vehicle Defects Interim Report

    SciTech Connect (OSTI)

    Siekmann, Adam [ORNL; Capps, Gary J [ORNL

    2012-12-01T23:59:59.000Z

    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.

  4. 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)

    2005-03-15T23:59:59.000Z

    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.

  5. Spectroscopy of Charge Carriers and Traps in Field-Doped Organic Semiconductors

    SciTech Connect (OSTI)

    Zhu, Xiaoyang; Frisbie, C Daniel

    2012-08-13T23:59:59.000Z

    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.

  6. Ultrasonic Tomography for Detecting and Locating Defects in Concrete Structures

    E-Print Network [OSTI]

    White, Joshua

    2012-07-16T23:59:59.000Z

    ....................................................... 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...

  7. Relative projective cover works for Broue's abelian defect group

    E-Print Network [OSTI]

    Thévenaz, Jacques

    University, Chiba, Japan Tue. 22 June, 2010 Joint work with J¨urgen M¨uller and Felix Noeske Brou´e's abelian that A is a block algebra of OG with a defect group P and that AN is a block algebra of ONG(P) which is the Brauer´e's abelian defect group conjecture holds for all primes p and for all block algebras of OG if G = Co3, where

  8. 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.

  9. Recovery Act – Transportation Electrification

    SciTech Connect (OSTI)

    Gogineni, Kumar

    2013-12-31T23:59:59.000Z

    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.

  10. Gradient Improvement by Removal of Identified Local Defects

    SciTech Connect (OSTI)

    R.L. Geng, W.A. Clemens, C.A. Cooper, H. Hayano, K. Watanabe

    2011-07-01T23:59:59.000Z

    Recent experience of ILC cavity processing and testing at Jefferson Lab has shown that some 9-cell cavities are quench limited at a gradient in the range of 15-25 MV/m. Further studies reveal that these quench limits are often correlated with sub-mm sized and highly localized geometrical defects at or near the equator weld. There are increasing evidence to show that these genetic defects have their origin in the material or in the electron beam welding process (for example due to weld irregularities or splatters on the RF surface and welding porosity underneath the surface). A local defect removal method has been proposed at Jefferson Lab by locally re-melting the niobium material. Several 1-cell cavities with known local defects have been treated by using the JLab local e-beam re-melting method, resulting in gradient and Q0 improvement. We also sent 9-cell cavities with known gradient limiting local defects to KEK for local grinding and to FNAL for global mechanical polishing. We report on the results of gradient improvements by removal of local defects in these cavities.

  11. Crystal defect studies using x-ray diffuse scattering

    SciTech Connect (OSTI)

    Larson, B.C.

    1980-01-01T23:59:59.000Z

    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.

  12. A detail study of defect models for cosmic structure formation

    E-Print Network [OSTI]

    A. Albrecht; R. A. Battye; J. Robinson

    1997-11-27T23:59:59.000Z

    We calculate predictions from wide class of `active' models of cosmic structure formation which allows us to scan the space of possible defect models. We calculate the linear cold dark matter power spectrum and Cosmic Microwave Background (CMB) anisotropies over all observable scales using a full linear Einstein-Boltzmann code. Our main result, which has already been reported, points to a serious problem reconciling the observed amplitude of the large-scale galaxy distribution with the COBE normalization. Here, we describe our methods and results in detail. The problem is present for a wide range of defect parameters, which can be used to represent potential differences among defect models, as well as possible systematic numerical errors. We explicitly examine the impact of varying the defect model parameters and we show how the results substantiate these conclusions. The standard scaling defect models are in serious conflict with the current data, and we show how attempts to resolve the problem by considering non-scaling defects or modified stress-energy components would require radical departures from what has become the standard picture.

  13. Charge and magnetic states of Mn-, Fe-, and Co-doped monolayer MoS{sub 2}

    SciTech Connect (OSTI)

    Lin, Xianqing [State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084 (China); Collaborative Innovation Center of Quantum Matter, Beijing 100084 (China); Department of Applied Physics, Zhejiang University of Technology, Hangzhou 310023 (China); Ni, Jun, E-mail: junni@mail.tsinghua.edu.cn [State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084 (China); Collaborative Innovation Center of Quantum Matter, Beijing 100084 (China)

    2014-07-28T23:59:59.000Z

    First-principles calculations have been performed to investigate the electronic and magnetic properties of monolayer MoS{sub 2} substitutionally doped with Mn, Fe, and Co in possible charge states (q). We find that the Mn, Fe, and Co dopants substituting for a Mo atom in monolayer MoS{sub 2} (Mn@Mo, Fe@Mo, and Co@Mo) are all magnetic in their neutral and charge states except in the highest positive charge states. Mn@Mo, Fe@Mo, and Co@Mo have the same highest negative charge states of q=?2 for chemical potential of electron just below the conduction band minimum, which corresponds to the electron doping. In the q=?2 state, Mn@Mo has a much larger magnetic moment than its neutral state with the antiferromagnetic coupling between the Mn dopant and its neighboring S atoms maintained, while Fe@Mo and Co@Mo have equal or smaller magnetic moments than their neutral states. The possible charge states of Mn@Mo, Fe@Mo, and Co@Mo and the variation of the magnetic moments for different dopants and charge states are due to the change of the occupation and energy of the anti-bonding defect levels in the band gap. The rich magnetic properties of the neutral and charge states suggest possible realization of the substitutionally Mn-, Fe-, and Co-doped monolayer MoS{sub 2} as dilute magnetic semiconductors.

  14. Effect of electrostatic field of implanted space charge in the slowing down of fast heavy nonrelativistic particles

    SciTech Connect (OSTI)

    Remizovich, F.S.; Rudenko, A.I.

    1980-08-01T23:59:59.000Z

    An analytic solution is obtained of the transport equation for fast particles allowing for the effect of the space-charge field. We investigate the dependence of the mean free path on the irradiation time, the flux density of the moving particles as a function of depth, and also the time-dependent spatial distribution of the density of the stopped particles. The influence of space charge leakage is analyzed.

  15. Oxygen Transport Membranes

    SciTech Connect (OSTI)

    S. Bandopadhyay

    2008-08-30T23:59:59.000Z

    The focus of this research was to develop new membrane materials by synthesizing different compounds and determining their defect structures, crystallographic structures and electrical properties. In addition to measuring electrical conductivity, oxygen vacancy concentration was also evaluated using thermogravimetry, Neutron diffraction and Moessbauer Spectroscopy. The reducing conditions (CO{sub 2}/CO/H{sub 2} gas mixtures with steam) as encountered in a reactor environment can be expected to have significant influence on the mechanical properties of the oxides membranes. Various La based materials with and without Ti were selected as candidate membrane materials for OTM. The maximum electrical conductivity of LSF in air as a function of temperature was achieved at < 600 C and depends on the concentration of Sr (acceptor dopant). Oxygen occupancy in LSF was estimated using Neutron diffractometry and Moessbauer Spectroscopy by measuring magnetic moment changes depending on the Fe{sup 3+} and Fe{sup 4+} ratio. After extensive studies of candidate materials, lanthanum ferrites (LSF and LSFT) were selected as the favored materials for the oxygen transport membrane (OTM). LSF is a very good material for an OTM because of its high electronic and oxygen ionic conductivity if long term stability and mechanical strength are improved. LSFT not only exhibits p-type behavior in the high oxygen activity regime, but also has n-type conduction in reducing atmospheres. Higher concentrations of oxygen vacancies in the low oxygen activity regime may improve the performance of LSFT as an OTM. The hole concentration is related to the difference in the acceptor and donor concentration by the relation p = [Sr'{sub La}]-[Ti{sm_bullet}{sub Fe}]. The chemical formulation predicts that the hole concentration is, p = 0.8-0.45 or 0.35. Experimental measurements indicated that p is about {approx} 0.35. The activation energy of conduction is 0.2 eV which implies that LSCF conducts via the small polaron conduction mechanism. Scanning transmission electron microscopy (STEM) and electron energy loss spectroscopy (EELS) were used to develop strategies to detect and characterize vacancy creation, dopant segregations and defect association in the oxygen conducting membrane material. The pO{sub 2} and temperature dependence of the conductivity, non-stoichiometry and thermal-expansion behavior of compositions with increasing complexity of substitution on the perovskite A and B sites were studied. Studies with the perovskite structure show anomalous behavior at low oxygen partial pressures (<10{sup -5} atm). The anomalies are due to non-equilibrium effects and can be avoided by using very strict criteria for the attainment of equilibrium. The slowness of the oxygen equilibration kinetics arises from two different mechanisms. In the first, a two phase region occurs between an oxygen vacancy ordered phase such as brownmillerite SrFeO{sub 2.5} and perovskite SrFeO{sub 3-x}. The slow kinetics is associated with crossing the two phase region. The width of the miscibility gap decreases with increasing temperature and consequently the effect is less pronounced at higher temperature. The preferred kinetic pathway to reduction of perovskite ferrites when the vacancy concentration corresponds to the formation of significant concentrations of Fe{sup 2+} is via the formation of a Ruddlesden-Popper (RP) phases as clearly observed in the case of La{sub 0.5}Sr{sub 0.5}FeO{sub 3-x} where LaSrFeO{sub 4} is found together with Fe. In more complex compositions, such as LSFTO, iron or iron rich phases are observed locally with no evidence for the presence of discrete RP phase. Fracture strength of tubular perovskite membranes was determined in air and in reducing atmospheric conditions. The strength of the membrane decreased with temperature and severity of reducing conditions although the strength distribution (Weibull parameter, m) was relatively unaltered. Surface and volume dominated the fracture origins and the overall fracture was purely transgranular. The dual phas

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

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

    to become a part of the Workplace Charging Challenge. "We are delighted to be the first health care institution in Maryland to provide charging stations for our employees, staff...

  17. Methods for reduction of charging emissions

    SciTech Connect (OSTI)

    Schuecker, F.J.; Schulte, H. [Krupp Uhde GmbH, Dortmund (Germany)

    1997-12-31T23:59:59.000Z

    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.

  18. Fast Methods for Bimolecular Charge Optimization

    E-Print Network [OSTI]

    Bardhan, Jaydeep P.

    We report a Hessian-implicit optimization method to quickly solve the charge optimization problem over protein molecules: given a ligand and its complex with a receptor, determine the ligand charge distribution that minimizes ...

  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)

    2002-01-01T23:59:59.000Z

    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. Systems and methods for forming defects on graphitic materials and curing radiation-damaged graphitic materials

    DOE Patents [OSTI]

    Ryu, Sunmin; Brus, Louis E.; Steigerwald, Michael L.; Liu, Haitao

    2012-09-25T23:59:59.000Z

    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.

  1. Free form hemispherical shaped charge

    DOE Patents [OSTI]

    Haselman, Jr., Leonard C. (Livermore, CA)

    1996-01-01T23:59:59.000Z

    A hemispherical shaped charge has been modified such that one side of the hemisphere is spherical and the other is aspherical allowing a wall thickness variation in the liner. A further modification is to use an elongated hemispherical shape. The liner has a thick wall at its pole and a thin wall at the equator with a continually decreasing wall thickness from the pole to the equator. The ratio of the wall thickness from the pole to the equator varies depending on liner material and HE shape. Hemispherical shaped charges have previously been limited to spherical shapes with no variations in wall thicknesses. By redesign of the basic liner thicknesses, the jet properties of coherence, stability, and mass distribution have been significantly improved.

  2. Defect studies in low-temperature-grown GaAs

    SciTech Connect (OSTI)

    Bliss, D.E.

    1992-11-01T23:59:59.000Z

    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.

  3. Charge

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWPSuccessAlamosCharacterization of Selective Binding of

  4. Charge

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWPSuccessAlamosCharacterization of Selective Binding of2 DOE Review of

  5. Charge

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWPSuccessAlamosCharacterization of Selective Binding of2 DOE Review

  6. Charge

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041clothAdvanced Materials Advanced. C o w l i t z CPlasma of the Rotating Wall Machine by David A.1

  7. Quarks with Integer Electric Charge

    E-Print Network [OSTI]

    J. LaChapelle

    2015-01-26T23:59:59.000Z

    Within the context of the Standard Model, quarks are placed in a $(\\mathbf{3},\\mathbf{2})\\oplus (\\mathbf{3},\\bar{\\mathbf{2}})$ matter field representation of $U_{EW}(2)$. Although the quarks carry unit intrinsic electric charge in this construction, anomaly cancellation constrains the Lagrangian in such a way that the quarks' associated currents couple to the photon with the usual 2/3 and 1/3 fractional electric charge associated with conventional quarks. The resulting model is identical to the Standard Model in the $SU_C(3)$ sector: However, in the $U_{EW}(2)$ sector it is similar but not necessarily equivalent. Off hand, the model appears to be phenomenologically equivalent to the conventional quark model in the electroweak sector for experimental conditions that preclude observation of individual constituent currents. On the other hand, it is conceivable that detailed analyses for electroweak reactions may reveal discrepancies with the Standard Model in high energy and/or large momentum transfer reactions. The possibility of quarks with integer electric charge strongly suggests the notion that leptons and quarks are merely different manifestations of the same underlying field. A speculative model is proposed in which a phase transition is assumed to occur between $SU_C(3)\\otimes U_{EM}(1)$ and $U_{EM}(1)$ regimes. This immediately; explains the equality of lepton/quark generations and lepton/hadron electric charge, relates neutrino oscillations to quark flavor mixing, reduces the free parameters of the Standard Model, and renders the issue of quark confinement moot.

  8. tt Charge asymmetry at hadron colliders

    E-Print Network [OSTI]

    Chapelain, Antoine

    2013-01-01T23:59:59.000Z

    We present the current status for the measurements of the ttbar charge asymmetry at the Tevatron and LHC colliders.

  9. Electrochemically controlled charging circuit for storage batteries

    DOE Patents [OSTI]

    Onstott, E.I.

    1980-06-24T23:59:59.000Z

    An electrochemically controlled charging circuit for charging storage batteries is disclosed. The embodiments disclosed utilize dc amplification of battery control current to minimize total energy expended for charging storage batteries to a preset voltage level. The circuits allow for selection of Zener diodes having a wide range of reference voltage levels. Also, the preset voltage level to which the storage batteries are charged can be varied over a wide range.

  10. INL Testing of Wireless Charging Systems

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

    investments and FOAs (Funding Opportunity Announcements) * Provide the charging, automotive, and electric utility industries with independent testing assessments and...

  11. Synchrotron radiation from massless charge

    E-Print Network [OSTI]

    Gal'tsov, D V

    2015-01-01T23:59:59.000Z

    Classical radiation power from an accelerated massive charge diverges in the zero-mass limit, while some general arguments suggest that strictly massless charge does not not radiate at all. On the other hand, the regularized classical radiation reaction force, though looking odd, is non-zero and finite. To clarify this controversy, we consider radiation problem in massless scalar quantum electrodynamics in the external magnetic field. In this framework, synchrotron radiation is found to be non-zero, finite, and essentially quantum. Its spectral distribution is calculated using Schwinger's proper time technique for {\\em ab initio} massless particle of zero spin. Provided $E^2\\gg eH$, the maximum in the spectrum is shown to be at $\\hbar \\omega=E/3$, and the average photon energy is $4E/9$. The normalized spectrum is universal, depending neither on $E$ nor on $H$. Quantum nature of radiation makes classical radiation reaction equation meaningless for massless charge. Our results are consistent with the view (sup...

  12. Electric Vehicle Charging as an Enabling Technology

    E-Print Network [OSTI]

    Electric Vehicle Charging as an Enabling Technology Prepared for the U.S. Department of Energy technologies, electric vehicles and the appurtenant charging infrastructure, is explored in detail to determine regarding system load profiles, vehicle charging strategies, electric vehicle adoption rates, and storage

  13. Optimal Decentralized Protocols for Electric Vehicle Charging

    E-Print Network [OSTI]

    Low, Steven H.

    into the electric power grid. EV charging increases the electricity demand, and potentially amplifies the peak1 Optimal Decentralized Protocols for Electric Vehicle Charging Lingwen Gan Ufuk Topcu Steven Low Abstract--We propose decentralized algorithms for optimally scheduling electric vehicle (EV) charging

  14. A User Programmable Battery Charging System 

    E-Print Network [OSTI]

    Amanor-Boadu, Judy M

    2013-05-07T23:59:59.000Z

    to provide the convenience of rare battery replacement and extend the periods between charges. This thesis proposes a user programmable charging system that can charge a Lithium ion battery from three different input sources, i.e. a wall outlet, a universal...

  15. EBS Radionuclide Transport Abstraction

    SciTech Connect (OSTI)

    J. Prouty

    2006-07-14T23:59:59.000Z

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment (TSPA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers advective transport and diffusive transport from a breached waste package. Advective transport occurs when radionuclides that are dissolved or sorbed onto colloids (or both) are carried from the waste package by the portion of the seepage flux that passes through waste package breaches. Diffusive transport occurs as a result of a gradient in radionuclide concentration and may take place while advective transport is also occurring, as well as when no advective transport is occurring. Diffusive transport is addressed in detail because it is the sole means of transport when there is no flow through a waste package, which may dominate during the regulatory compliance period in the nominal and seismic scenarios. The advective transport rate, when it occurs, is generally greater than the diffusive transport rate. Colloid-facilitated advective and diffusive transport is also modeled and is presented in detail in Appendix B of this report.

  16. Space Charge and Equilibrium Emittances in Damping Rings

    E-Print Network [OSTI]

    Venturini, Marco; Oide, Katsunobu; Wolski, Andy

    2006-01-01T23:59:59.000Z

    SPACE CHARGE AND EQUILIBRIUM EMITTANCES IN DAMPING RINGS ?for the pos- sible impact of space charge on the equilibriumrings. INTRODUCTION Direct space charge effects have the

  17. The high current transport experiment for heavy ion inertial fusion

    SciTech Connect (OSTI)

    Prost, L.R.; Baca, D.; Bieniosek, F.M.; Celata, C.M.; Faltens, A.; Henestroza, E.; Kwan, J.W.; Leitner, M.; Seidl, P.A.; Waldron, W.L.; Cohen, R.; Friedman, A.; Grote, D.; Lund, S.M.; Molvik, A.W.; Morse, E.

    2004-05-01T23:59:59.000Z

    The High Current Experiment (HCX) at Lawrence Berkeley National Laboratory is part of the US program to explore heavy-ion beam transport at a scale representative of the low-energy end of an induction linac driver for fusion energy production. The primary mission of this experiment is to investigate aperture fill factors acceptable for the transport of space-charge-dominated heavy-ion beams at high intensity (line charge density {approx} 0.2 {micro}C/m) over long pulse durations (4 {micro}s) in alternating gradient focusing lattices of electrostatic or magnetic quadrupoles. This experiment is testing transport issues resulting from nonlinear space-charge effects and collective modes, beam centroid alignment and steering, envelope matching, image charges and focusing field nonlinearities, halo and, electron and gas cloud effects. We present the results for a coasting 1 MeV K{sup +} ion beam transported through ten electrostatic quadrupoles. The measurements cover two different fill factor studies (60% and 80% of the clear aperture radius) for which the transverse phase-space of the beam was characterized in detail, along with beam energy measurements and the first halo measurements. Electrostatic quadrupole transport at high beam fill factor ({approx}80%) is achieved with acceptable emittance growth and beam loss, even though the initial beam distribution is not ideal (but the emittance is low) nor in thermal equilibrium. We achieved good envelope control, and rematching may only be needed every ten lattice periods (at 80% fill factor) in a longer lattice of similar design. We also show that understanding and controlling the time dependence of the envelope parameters is critical to achieving high fill factors, notably because of the injector and matching section dynamics.

  18. Quantum transport via evanescent waves in undoped graphene

    E-Print Network [OSTI]

    M. I. Katsnelson

    2011-01-13T23:59:59.000Z

    Charge carriers in graphene are chiral quasiparticles ("massless Dirac fermions"). Graphene provides therefore an amazing opportunity to study subtle quantum relativistic effects in condensed matter experiment. Here I review a theory of one of these unusual features of graphene, a "pseudodiffusive" transport in the limit of zero charge carrier concentration, which is related to existence of zero-modes of the Dirac operator and to the Zitterbewegung of unltrarelativistic particles. A conformal mapping technique is a powerful mathematical tool to study these phenomena, as demonstrated here, using the Aharonov-Bohm effect in graphene rings with Corbino geometry as an example.

  19. Radioactive Material Transportation Practices

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2002-09-23T23:59:59.000Z

    Establishes standard transportation practices for Departmental programs to use in planning and executing offsite shipments of radioactive materials including radioactive waste. Does not cancel other directives.

  20. Alternative Fuel Transportation Program

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

    Merit Review: EPAct State and Alternative Fuel Provider Fleets "Alternative Fuel Transportation Program" Dana O'Hara, DOE Ted Sears, NREL Vehicle Technologies Program June 20,...

  1. Transportation and its Infrastructure

    E-Print Network [OSTI]

    2007-01-01T23:59:59.000Z

    Options for Liquid Biofuels Development in Ireland. SEI, 562006: Outlook for advanced biofuels. Energy Policy, 34(17),40 pp. IEA, 2004c: Biofuels for Transport: An International

  2. Transportation Energy Futures

    E-Print Network [OSTI]

    DeLuchi, Mark A.

    1989-01-01T23:59:59.000Z

    TRANSPORTATION ment of Oil Shale Technology. Washing- ton,interest and investments in oil shale, ethanol, coal liquidsbiomass materials, coal, oil shale, tar sands, natural gas,

  3. Sustainable Transportation (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-09-01T23:59:59.000Z

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

  4. Atomic control and characterization of surface defect states of TiO{sub 2} terminated SrTiO{sub 3} single crystals

    SciTech Connect (OSTI)

    Kareev, M.; Prosandeev, S.; Liu, J.; Gan, C.; Kareev, A.; Xiao, Min; Chakhalian, J. [University of Arkansas, Fayetteville, Arkansas 72701 (United States); Freeland, J. W. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2008-08-11T23:59:59.000Z

    By using an alternative wet-etch procedure, we have obtained high-quality atomically flat TiO{sub 2} terminated surfaces of SrTiO{sub 3} single crystals with the morphology equivalent to that of the conventional wet-etch methods. By applying a combined power of photoluminescence (PL) spectroscopy, reflection high-energy electron diffraction, atomic force microscopy imaging, and soft x-ray absorption (XAS), we were able to identify and monitor the complex evolution of oxygen defect states and Ti valency at the surface and near-surface layers. Our experiments revealed a high level of local defects resulting in the presence of the Ti{sup 3+} states at the surface. We have developed a method to control the defect states capable of a marked reduction of the defect concentration. We have demonstrated that the PL and XAS are able to distinguish the surface-related Ti{sup 3+} states from oxygen vacancies trapping charge transfer vibronic excitons that define the PL intensity. The experimental findings will have important implications for the growth of high-quality ultrathin complex oxide heterostructures.

  5. Atomic control and characterization of surface defect states of TiO(sub 2) terminated SrTiO(sub 3) single crystals.

    SciTech Connect (OSTI)

    Kareev, M.; Prosandeev, S.; Liu, J.; Gan, C.; Kareev, A.; Freeland, J. W.; Xiao, M.; Chakhalian, J.; Univ. of Arkansas

    2008-08-11T23:59:59.000Z

    By using an alternative wet-etch procedure, we have obtained high-quality atomically flat TiO{sub 2} terminated surfaces of SrTiO{sub 3} single crystals with the morphology equivalent to that of the conventional wet-etch methods. By applying a combined power of photoluminescence (PL) spectroscopy, reflection high-energy electron diffraction, atomic force microscopy imaging, and soft x-ray absorption (XAS), we were able to identify and monitor the complex evolution of oxygen defect states and Ti valency at the surface and near-surface layers. Our experiments revealed a high level of local defects resulting in the presence of the Ti{sup 3+} states at the surface. We have developed a method to control the defect states capable of a marked reduction of the defect concentration. We have demonstrated that the PL and XAS are able to distinguish the surface-related Ti{sup 3+} states from oxygen vacancies trapping charge transfer vibronic excitons that define the PL intensity. The experimental findings will have important implications for the growth of high-quality ultrathin complex oxide heterostructures.

  6. Electricity Demand of PHEVs Operated by Private Households and Commercial Fleets: Effects of Driving and Charging Behavior

    SciTech Connect (OSTI)

    John Smart; Matthew Shirk; Ken Kurani; Casey Quinn; Jamie Davies

    2010-11-01T23:59:59.000Z

    Automotive and energy researchers have made considerable efforts to predict the impact of plug-in hybrid vehicle (PHEV) charging on the electrical grid. This work has been done primarily through computer modeling and simulation. The US Department of Energy’s (DOE) Advanced Vehicle Testing Activity (AVTA), in partnership with the University of California at Davis’s Institute for Transportation Stuides, have been collecting data from a diverse fleet of PHEVs. The AVTA is conducted by the Idaho National Laboratory for DOE’s Vehicle Technologies Program. This work provides the opportunity to quantify the petroleum displacement potential of early PHEV models, and also observe, rather than simulate, the charging behavior of vehicle users. This paper presents actual charging behavior and the resulting electricity demand from these PHEVs operating in undirected, real-world conditions. Charging patterns are examined for both commercial-use and personal-use vehicles. Underlying reasons for charging behavior in both groups are also presented.

  7. Residual dust charges in discharge afterglow

    SciTech Connect (OSTI)

    Coueedel, L.; Mikikian, M.; Boufendi, L.; Samarian, A. A. [GREMI - Groupe de Recherches sur l'Energetique des Milieux Ionises, CNRS/Universite d'Orleans, 14 rue d'Issoudun, 45067 Orleans Cedex 2 (France); School of Physics A28, University of Sydney, NSW 2006 (Australia)

    2006-08-15T23:59:59.000Z

    An on-ground measurement of dust-particle residual charges in the afterglow of a dusty plasma was performed in a rf discharge. An upward thermophoretic force was used to balance the gravitational force. It was found that positively charged, negatively charged, and neutral dust particles coexisted for more than 1 min after the discharge was switched off. The mean residual charge for 200-nm-radius particles was measured. The dust particle mean charge is about -5e at a pressure of 1.2 mbar and about -3e at a pressure of 0.4 mbar.

  8. 2006 TRANSPORTATION TOMORROW SURVEY JOINT PROGRAM IN TRANSPORTATION

    E-Print Network [OSTI]

    Toronto, University of

    2006 TRANSPORTATION TOMORROW SURVEY JOINT PROGRAM IN TRANSPORTATION UNIVERSITY OF TORONTO 2006 Transportation Tomorrow Survey Data Presentation #12;2006 TRANSPORTATION TOMORROW SURVEY JOINT PROGRAM IN TRANSPORTATION UNIVERSITY OF TORONTO City of Hamilton City of Kawartha Lakes City of Guelph City of Brantford

  9. Predicting the Occurrence of Cosmetic Defects in Automotive Skin Panels

    SciTech Connect (OSTI)

    Hazra, S.; Williams, D.; Roy, R. [University of Warwick, Gibbet Hill Road, Coventry CV4 7AL (United Kingdom); Aylmore, R.; Allen, M.; Hollingdale, D. [Land Rover, Banbury Rd, Gaydon, Warwick, CV35 0RR (United Kingdom)

    2011-05-04T23:59:59.000Z

    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.

  10. Developmental defects in zebrafish for classification of EGF pathway inhibitors

    SciTech Connect (OSTI)

    Pruvot, Benoist; Curé, Yoann; Djiotsa, Joachim; Voncken, Audrey; Muller, Marc, E-mail: m.muller@ulg.ac.be

    2014-01-15T23:59:59.000Z

    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.

  11. Vacuum charge fractionlization re-examined

    E-Print Network [OSTI]

    Y. Nogami

    2008-08-01T23:59:59.000Z

    We consider a model of a quantized fermion field that is based on the Dirac equation in one dimensional space and re-examine how the fermion number of the vacuum, or the vacuum charge, varies when an external potential is switched on. With this model, fractionization of the vacuum charge has been illustrated in the literature by showing that the external potential can change the vacuum charge from zero to a fractional number. Charge conservation then appears violated in this process. This is because the charge that has been examined in this context is only a part of the total charge of the vacuum. The total charge is conserved. It is not fractionalized unless the Dirac equation has a zero mode. Two other confusing aspects are discussed. One is concerned with the usage of the continuum limit and the other with the regularization of the current operator. Implications of these aspects of the vacuum problem are explored.

  12. Native defects in tetradymite Bi2(TexSe3-x) topological insulators

    SciTech Connect (OSTI)

    Wang, Lin-Lin [Ames Laboratory; Huang, Mianliang [South Dakota School of Mines; Thimmaiah, Srinivasa [Ames Laboratory; Alam, Aftab [Ames Laboratory; Budko, Sergey L. [Ames Laboratory; Kaminski, Adam [Ames Laboratory; Lograsso, Thomas A. [Ames Laboratory; Canfield, Paul [Ames Laboratory; Johnson, Duane D. [Ames Laboratory

    2013-03-08T23:59:59.000Z

    Formation energies of native defects in Bi2(TexSe3-x), with comparison to ideal Bi2Te2S, are calculated in density-functional theory to assess transport properties. Bi2Se3 is found to be n type for both Bi- and Se-rich growth conditions, while Bi2Te3 changes from n to p type going from Te- to Bi-rich conditions, as observed. Bi2Te2Se and Bi2Te2S are generally n type, explaining observed heavily doped n-type behavior in most samples. A (0/-) transition level at 16 meV above valence-band maximum for Bi on Te antisites in Bi2Te2Se is related to the observed thermally active transport gap causing a p-to-n transition at low temperature. Bi2(TexSe3-x) with x>2 are predicted to have high bulk resistivity due to effective carrier compensation when approaching the n-to-p crossover. Predicted behaviors are confirmed from characterization of our grown single crystals.

  13. Demand Charges | Open Energy Information

    Open Energy Info (EERE)

    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 onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand JumpConceptual Model,DOE Facility DatabaseMichigan: Energy Resources Jump to:Delta, Ohio:Charges Jump

  14. LUNAR DUST GRAIN CHARGING BY ELECTRON IMPACT: COMPLEX ROLE OF SECONDARY ELECTRON EMISSIONS IN SPACE ENVIRONMENTS

    SciTech Connect (OSTI)

    Abbas, M. M.; Craven, P. D.; LeClair, A. C.; Spann, J. F. [NASA-Marshall Space Flight Center, Huntsville, AL 35812 (United States); Tankosic, D., E-mail: Mian.M.Abbas@nasa.go [USRA/NASA-Marshall Space Flight Center, Huntsville, AL 35805 (United States)

    2010-08-01T23:59:59.000Z

    Dust grains in various astrophysical environments are generally charged electrostatically by photoelectric emissions with radiation from nearby sources, or by electron/ion collisions by sticking or secondary electron emissions (SEEs). The high vacuum environment on the lunar surface leads to some unusual physical and dynamical phenomena involving dust grains with high adhesive characteristics, and levitation and transportation over long distances. Knowledge of the dust grain charges and equilibrium potentials is important for understanding a variety of physical and dynamical processes in the interstellar medium, and heliospheric, interplanetary/planetary, and lunar environments. It has been well recognized that the charging properties of individual micron-/submicron-size dust grains are expected to be substantially different from the corresponding values for bulk materials. In this paper, we present experimental results on the charging of individual 0.2-13 {mu}m size dust grains selected from Apollo 11 and 17 dust samples, and spherical silica particles by exposing them to mono-energetic electron beams in the 10-200 eV energy range. The dust charging process by electron impact involving the SEEs discussed is found to be a complex charging phenomenon with strong particle size dependence. The measurements indicate substantial differences between the polarity and magnitude of the dust charging rates of individual small-size dust grains, and the measurements and model properties of corresponding bulk materials. A more comprehensive plan of measurements of the charging properties of individual dust grains for developing a database for realistic models of dust charging in astrophysical and lunar environments is in progress.

  15. http://tti.tamu.edu Multi-modal Transportation > Highway Transportation > Trucking > Railroad transportation > Public transit > Rural transportation > Rural transit > Freight

    E-Print Network [OSTI]

    http://tti.tamu.edu Multi-modal Transportation > Highway Transportation > Trucking > Railroad transportation > Public transit > Rural transportation > Rural transit > Freight pipeline transportation >>> Transportation operat > Freight traffic > Commodities > Travel time > Travel demand > http

  16. 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)

    1997-01-01T23:59:59.000Z

    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.

  17. Apparatus and method for defect testing of integrated circuits

    SciTech Connect (OSTI)

    Cole, E.I. Jr.; Soden, J.M.

    2000-02-29T23:59:59.000Z

    An apparatus and method for defect and failure-mechanism testing of integrated circuits (ICs) is disclosed. The apparatus provides an operating voltage, V(DD), to an IC under test and measures a transient voltage component, V(DDT), signal that is produced in response to switching transients that occur as test vectors are provided as inputs to the IC. The amplitude or time delay of the V(DDT) signal can be used to distinguish between defective and defect-free (i.e. known good) ICs. The V(DDT) signal is measured with a transient digitizer, a digital oscilloscope, or with an IC tester that is also used to input the test vectors to the IC. The present invention has applications for IC process development, for the testing of ICs during manufacture, and for qualifying ICs for reliability.

  18. Apparatus and method for defect testing of integrated circuits

    DOE Patents [OSTI]

    Cole, Jr., Edward I. (Albuquerque, NM); Soden, Jerry M. (Placitas, NM)

    2000-01-01T23:59:59.000Z

    An apparatus and method for defect and failure-mechanism testing of integrated circuits (ICs) is disclosed. The apparatus provides an operating voltage, V.sub.DD, to an IC under test and measures a transient voltage component, V.sub.DDT, signal that is produced in response to switching transients that occur as test vectors are provided as inputs to the IC. The amplitude or time delay of the V.sub.DDT signal can be used to distinguish between defective and defect-free (i.e. known good) ICs. The V.sub.DDT signal is measured with a transient digitizer, a digital oscilloscope, or with an IC tester that is also used to input the test vectors to the IC. The present invention has applications for IC process development, for the testing of ICs during manufacture, and for qualifying ICs for reliability.

  19. INLAND PORT TRANSPORTATION EVALUATION GUIDE

    E-Print Network [OSTI]

    Texas at Austin, University of

    INLAND PORT TRANSPORTATION EVALUATION GUIDE by Robert Harrison, Center for Transportation Research Transportation Institute, The Texas A&M University System; and Jolanda Prozzi, Center for Transportation Research, The University of Texas at Austin CENTER FOR TRANSPORTATION RESEARCH Bureau of Engineering Research

  20. MAESTRAEN TRANSPORTE ESPECIALIZACINEN

    E-Print Network [OSTI]

    Vásquez, Carlos

    investigaciones que permitan la comprensión de distintos componentes delsistema del transporte así como para Investigación de Operaciones y Redes de transporte Medidas y Administración del Tránsito Tecnologías de

  1. Packaging and Transportation Safety

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2003-04-04T23:59:59.000Z

    To establish safety requirements for the proper packaging and transportation of Department of Energy (DOE)/National Nuclear Security Administration (NNSA) offsite shipments and onsite transfers of hazardous materials and for modal transport. Cancels DOE O 460.1A. Canceled by DOE O 460.1C.

  2. Packaging and Transportation Safety

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2010-05-14T23:59:59.000Z

    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. Cancels DOE O 460.1B, 5-14-10

  3. Expert systems in transportation

    SciTech Connect (OSTI)

    O'Leary, K.P.

    1988-01-01T23:59:59.000Z

    The 5 papers in the report deal with the following areas: Knowledge representation and software selection for expert-systems design; Expert-system architecture for retaining-wall design; Development of expert-systems technology in the California Department of Transportation; Development of an expert system to assist in the interactive graphic transit system design process; Expert systems development for contingency transportation planing.

  4. DECAY CONSTANTS OF CHARGED PSEUDO-SCALAR MESONS

    E-Print Network [OSTI]

    - and D+ s decays, the existence of a charged Higgs boson (or any other charged object beyond the Standard

  5. DECAY CONSTANTS OF CHARGED PSEUDO-SCALAR MESONS

    E-Print Network [OSTI]

    , the existence of a charged Higgs boson (or any other charged object beyond the Standard Model) would modify

  6. I{sub DDQ} Testing and Defect Classes: A Tutorial

    SciTech Connect (OSTI)

    Soden, J.M. [Sandia National Labs., Albuquerque, NM (United States); Hawkins, C.F. [New Mexico State Univ., Albuquerque, NM (United States). Dept. of Electrical and Computer Engineering

    1994-12-31T23:59:59.000Z

    I{sub DDQ} testing of CMOSICs is a technique for production quality and reliability improvement, design validation, and failure analysis. The origin and basic concepts of I{sub DDQ} testing are reviewed. The relationship of I{sub DDQ} testing to other test methods is considered in the context of the whole IC life cycle from design, fabrication, and test through end use. A comprehensive test strategy is described that uses defect classes based on defect electrical properties rather than traditional fault models.

  7. Multi-level scanning method for defect inspection

    DOE Patents [OSTI]

    Bokor, Jeffrey (Oakland, CA); Jeong, Seongtae (Richmond, CA)

    2002-01-01T23:59:59.000Z

    A method for performing scanned defect inspection of a collection of contiguous areas using a specified false-alarm-rate and capture-rate within an inspection system that has characteristic seek times between inspection locations. The multi-stage method involves setting an increased false-alarm-rate for a first stage of scanning, wherein subsequent stages of scanning inspect only the detected areas of probable defects at lowered values for the false-alarm-rate. For scanning inspection operations wherein the seek time and area uncertainty is favorable, the method can substantially increase inspection throughput.

  8. On the material geometry of continuously defective corrugated graphene sheets

    E-Print Network [OSTI]

    Andrzej Trzesowski

    2014-12-22T23:59:59.000Z

    Geometrical objects describing the material geometry of continuously defective graphene sheets are introduced and their compatibility conditions are formulated. Effective edge dislocations embedded in the Riemann-Cartan material space and defined by their scalar density and by local Burgers vectors, are considered. The case of secondary curvature-type defects created by this distribution of dislocations is analysed in terms of the material space. The variational geometry of the material space closely related with the existence of a characteristic length parameter is proposed. The formula which describes, in a reference temperature, the influence of dislocations on the material Riemannian metric, is given.

  9. Positive muon and the positron as probes of defects

    SciTech Connect (OSTI)

    Lynn, K G

    1980-01-01T23:59:59.000Z

    The positive muon and the positron are each being used nowadays to investigate defects in condensed matter. A brief summary of the experimental methods employed with each particle is given in this paper. Similarities and differences between the behavior of the two leptons when implanted in consensed matter are pointed out, and by means of a comparison between muon and positron data in Al it is shown that the combination of muon and positron experiments can serve as a useful new probe of defects in solids.

  10. On the defect induced gauge and Yukawa fields in graphene

    E-Print Network [OSTI]

    Corneliu Sochichiu

    2011-03-08T23:59:59.000Z

    We consider lattice deformations (both continuous and topological) in the hexagonal lattice Hubbard model in the tight binding approximation to graphene, involving operators with the range up to next-to-neighbor. In the low energy limit, we find that these deformations give rise to couplings of the electronic Dirac field to an external scalar (Yukawa) and gauge fields. The fields are expressed in terms of original defects. As a by-product we establish that the next-to-nearest order is the minimal range of deformations which produces the complete gauge and scalar fields. We consider an example of Stone--Wales defect, and find the associated gauge field.

  11. Effect of dimerization on dynamics of spin-charge separation in Pariser-Parr-Pople model: A time-dependent density matrix renormalization group study

    E-Print Network [OSTI]

    Tirthankar Dutta; S. Ramasesha

    2011-12-29T23:59:59.000Z

    We investigate the effect of static electron-phonon coupling, on real-time dynamics of spin and charge transport in $\\pi$-conjugated polyene chains. The polyene chain is modeled by the Pariser-Parr-Pople Hamiltonian with dimerized nearest-neighbor parameter $t_{0}(1+\\delta)$ for short bonds and $t_{0}(1-\\delta)$ for long bonds, and long-range electron-electron interactions. We follow the time evolution of the spin and charge using time-dependent density matrix renormalization group technique, when a hole is injected at one end of the chain in its ground state. We find that spin and charge dynamics followed through spin and charge velocities, depend both on chain length and extent of dimerization, $\\delta$. Analysis of the results requires focusing on physical quantities such as average spin and charge polarizations, particularly in the large dimerization limit. In the dimerization range 0.0 $\\le$ $\\delta$ $\\le$ 0.15, spin-charge dynamics is found to have a well defined behavior, with spin-charge separation (measured as the ratio of charge velocity to spin velocity) as well as, the total amount of charge and spin transported in a given time, along the chain, decreasing as dimerization increases. However, in the range 0.3 $\\le$ $\\delta$ $\\le$ 0.5, it is observed that the dynamics of spin and charge transport becomes complicated. It is observed that for large $\\delta$ values, spin-charge separation is suppressed and the injected hole fails to travel the entire length of the chain.

  12. Improving Efficiency and Equity in Transportation Finance

    E-Print Network [OSTI]

    Watts, Michael

    2006-01-01T23:59:59.000Z

    Fueling Transportation Finance. ” Ian W. H. Parry andFueling Transportation Finance. ” Transportation ResearchFueling Transportation Finance: A Primer on the Gas Tax •

  13. Sandia Energy - Transportation Energy Systems Analysis

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

    Transportation Energy Systems Analysis Home Transportation Energy Predictive Simulation of Engines Transportation Energy Systems Analysis Transportation Energy Systems AnalysisTara...

  14. Photocharge Transport and Recombination Measurements in Amorphous Silicon Films and Solar Cells by Photoconductive Frequency Mixing: Final Subcontract Report: 13 May 1994 - 15 January 1998

    SciTech Connect (OSTI)

    Braunstein, R.; Tang, Y.; Dong, S.; Liebe, J.; Sun, G.; Kattwinkel, A. (University of California: Los Angeles, California)

    1999-05-04T23:59:59.000Z

    This report describes work performed during this subcontract by the University of California. The photoconductivity, lifetime, and drift mobility of intrinsic hydrogenated amorphous silicon (a-Si:H), hydrogenated amorphous silicon carbide (a-SiC:H), and hydrogenated amorphous silicon germanium (a-SiGe:H) were determined using a photomixing technique in the as prepared and light-soaked states. In addition to the decay of the photoconductivity and electron lifetime, continuous decay of the electron drift mobility was found during the light-soaking process (Staebler-Wronski effect). Experimental data were fitted to a stretched exponential law. Different stretched-exponential parameters for photoconductivity, lifetime, and drift mobility were obtained, which indicates the production of defects with different generation kinetics upon light soaking. The transport properties of intrinsic a-Si:H samples (which were produced by the hot-wire technique at NREL at different substrate temperatures such that the hydrogen content ranged from >10% to <1%), were systematically studied. It was found that with increasing substrate temperature, the lifetime, the drift mobility, and the photoconductivity decreased, but the Urbach energy ({approx} 0.1 eV below the conduction band) increased. These results indicate that for the a-Si:H films with increasing deposition temperature, the density of positively charged, negatively charged, and neutral defects all show a tendency to increase, in agreement with the results observed by other workers employing other measurement techniques. Researchers also found that the drift mobility of these samples increases and the lifetime decreases with increasing electric field, while the mt product is essentially independent of the electric field in the range of 1,000-10,000 V/cm. The electric field dependence of mobility (Dm) /m0/ (DE) in the as-grown or/and annealed states are always larger than that in the light-soaked state. This electric field dependence of mobility can be explained by the existence of long-range potential fluctuations. Photoemission measurements in air were performed on a-Si:H, a-SiC:H, and transparent conducting oxide layers, and revealed inhomogeneities of composition or surface contamination.

  15. Transportation activity analysis using smartphones

    E-Print Network [OSTI]

    Xiao, Yu

    Transportation activity surveys investigate when, where and how people travel in urban areas to provide information necessary for urban transportation planning. In Singapore, the Land Transport Authority (LTA) carries out ...

  16. Theory of transport phenomena in polycrystalline lead chalcogenide films. Mobility. Nondegenerate statistics

    SciTech Connect (OSTI)

    Atakulov, Sh. B., E-mail: atakulovsh@mail.ru; Zaynolobidinova, S. M. [Fergana State University (Uzbekistan); Nabiev, G. A., E-mail: gulamnabi@mail.ru [Fergana Polytechnical Institute (Uzbekistan); Nabiyev, M. B. [Fergana State University (Uzbekistan); Yuldashev, A. A. [Fergana Polytechnical Institute (Uzbekistan)

    2013-07-15T23:59:59.000Z

    The mobility of nondegenerate electrons in quasi-single-crystal and polycrystalline PbTe films is experimentally investigated. The results obtained are compared with the data for bulk crystals at the same charge-carrier concentration. Under the assumption of limitation of the charge-carrier mobility by intercrystallite potential barriers, electron transport in an electric field is theoretically considered. The theoretical results are in good agreement with the experiment.

  17. Fundamental Studies of Charge Migration and Delocalization Relevant to Solar Energy Conversion

    SciTech Connect (OSTI)

    Michael J. Therien

    2012-06-01T23:59:59.000Z

    This program aimed to understand the molecular-level principles by which complex chemical systems carry out photochemical charge separation, transport, and storage, and how these insights could impact the design of practical solar energy conversion and storage devices. Towards these goals, this program focused on: (1) carrying out fundamental mechanistic and transient dynamical studies of proton-coupled electron-transfer (PCET) reactions; (2) characterizing and interrogating via electron paramagnetic resonance (EPR) spectroscopic methods novel conjugated materials that feature large charge delocalization lengths; and (3) exploring excitation delocalization and migration, as well as polaron transport properties of meso-scale assemblies that are capable of segregating light-harvesting antennae, nanoscale wire-like conduction elements, and distinct oxidizing and reducing environments.

  18. Single-electron quantum dot in Si/SiGe with integrated charge sensing C. B. Simmons,a

    E-Print Network [OSTI]

    Coppersmith, Susan N.

    Single-electron quantum dot in Si/SiGe with integrated charge sensing C. B. Simmons,a Madhu that are important for quantum information processing. Si/SiGe is of interest for semiconductor spin qubits and measurement of a top-gated quantum dot occupied by a single electron in a Si/SiGe heterostructure. Transport

  19. Multiphase transport model for heavy ion collisions at RHIC

    E-Print Network [OSTI]

    Zi-wei Lin; Subrata Pal; C. M. Ko; Bao-An Li; Bin Zhang

    2001-05-18T23:59:59.000Z

    Using a multiphase transport model (AMPT) with both partonic and hadronic interactions, we study the multiplicity and transverse momentum distributions of charged particles such as pions, kaons and protons in central Au+Au collisions at RHIC energies. Effects due to nuclear shadowing and jet quenching on these observables are also studied. We further show preliminary results on the production of multistrange baryons from the strangeness-exchange reactions during the hadronic stage of heavy ion collisions.

  20. Study of Electron Transport and Amplification in Diamond

    SciTech Connect (OSTI)

    Muller, Erik M.; Ben-Zvi, Ilan

    2013-03-31T23:59:59.000Z

    As a successful completion of this award, my group has demonstrated world-leading electron gain from diamond for use in a diamond-amplified photocathode. Also, using high-resolution photoemission measurements we were able to uncover exciting new physics of the electron emission mechanisms from hydrogen terminated diamond. Our work, through the continued support of HEP, has resulted in a greater understanding of the diamond material science, including current limits, charge transport modeling, and spatial uniformity.