Sample records for timing trapping mechanism

  1. Investigation of Aging Mechanisms in Lean NOx Traps

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

    Annual Merit Review 1 Investigation of Aging Mechanisms in Lean NOx Traps Mark Crocker Center for Applied Energy Research, University of Kentucky May 20, 2009 This presentation...

  2. Freely floating structures trapping time-harmonic water waves (revisited)

    E-Print Network [OSTI]

    Nikolay Kuznetsov; Oleg Motygin

    2014-10-22T23:59:59.000Z

    We study the coupled small-amplitude motion of the mechanical system consisting of infinitely deep water and a structure immersed in it. The former is bounded above by a free surface, whereas the latter is formed by an arbitrary finite number of surface-piercing bodies floating freely. The mathematical model of time-harmonic motion is a spectral problem in which the frequency of oscillations serves as the spectral parameter. It is proved that there exist axisymmetric structures consisting of $N \\geq 2$ bodies; every structure has the following properties: (i) a time-harmonic wave mode is trapped by it; (ii) some of its bodies (may be none) are motionless, whereas the rest of the bodies (may be none) are heaving at the same frequency as water. The construction of these structures is based on a generalization of the semi-inverse procedure applied earlier for obtaining trapping bodies that are motionless although float freely.

  3. First Exit Times of Harmonically Trapped Particles: A Didactic Review

    E-Print Network [OSTI]

    D. S. Grebenkov

    2014-11-13T23:59:59.000Z

    We revise the classical problem of characterizing first exit times of a harmonically trapped particle whose motion is described by one- or multi-dimensional Ornstein-Uhlenbeck process. We start by recalling the main derivation steps of a propagator using Langevin and Fokker-Planck equations. The mean exit time, the moment-generating function, and the survival probability are then expressed through confluent hypergeometric functions and thoroughly analyzed. We also present a rapidly converging series representation of confluent hypergeometric functions that is particularly well suited for numerical computation of eigenvalues and eigenfunctions of the governing Fokker-Planck operator. We discuss several applications of first exit times such as detection of time intervals during which motor proteins exert a constant force onto a tracer in optical tweezers single-particle tracking experiments; adhesion bond dissociation under mechanical stress; characterization of active periods of trend following and mean-reverting strategies in algorithmic trading on stock markets; relation to the distribution of first crossing times of a moving boundary by Brownian motion. Some extensions are described, including diffusion under quadratic double-well potential and anomalous diffusion.

  4. Spin Self-Rephasing and Very Long Coherence Times in a Trapped Atomic Ensemble

    SciTech Connect (OSTI)

    Deutsch, C.; Reinhard, F.; Schneider, T.; Laloee, F.; Reichel, J. [Laboratoire Kastler Brossel, ENS, UPMC, CNRS, 24 rue Lhomond, 75005 Paris (France); Ramirez-Martinez, F.; Lacroute, C.; Rosenbusch, P. [LNE-SYRTE, Observatoire de Paris, UPMC, CNRS, 61 av de l'Observatoire, 75014 Paris (France); Fuchs, J. N.; Piechon, F. [Laboratoire de Physique des Solides, CNRS UMR 8502, Univ. Paris-Sud, 91405 Orsay (France)

    2010-07-09T23:59:59.000Z

    We perform Ramsey spectroscopy on the ground state of ultracold {sup 87}Rb atoms magnetically trapped on a chip in the Knudsen regime. Field inhomogeneities over the sample should limit the 1/e contrast decay time to about 3 s, while decay times of 58{+-}12 s are actually observed. We explain this surprising result by a spin self-rephasing mechanism induced by the identical spin rotation effect originating from particle indistinguishability. We propose a theory of this synchronization mechanism and obtain good agreement with the experimental observations. The effect is general and may appear in other physical systems.

  5. Drunken robber, tipsy cop: First passage times, mobile traps, and Hopf bifurcations

    E-Print Network [OSTI]

    Justin C. Tzou; Shuangquan Xie; Theodore Kolokolnikov

    2014-10-03T23:59:59.000Z

    For a random walk on a confined one-dimensional domain, we consider mean first passage times (MFPT) in the presence of a mobile trap. The question we address is whether a mobile trap can improve capture times over a stationary trap. We consider two scenarios: a randomly moving trap and an oscillating trap. In both cases, we find that a stationary trap actually performs better (in terms of reducing expected capture time) than a very slowly moving trap; however, a trap moving sufficiently fast performs better than a stationary trap. We explicitly compute the thresholds that separate the two regimes. In addition, we find a surprising relation between the oscillating trap problem and a moving-sink problem that describes reduced dynamics of a single spike in a certain regime of the Gray-Scott model. Namely, the above-mentioned threshold corresponds precisely to a Hopf bifurcation that induces oscillatory motion in the location of the spike. We use this correspondence to prove the uniqueness of the Hopf bifurcation.

  6. High-k shallow traps observed by charge pumping with varying discharging times

    SciTech Connect (OSTI)

    Ho, Szu-Han; Chen, Ching-En; Tseng, Tseung-Yuen [Department of Electronics Engineering, National Chiao Tung University, Hsinchu 300, Taiwan (China); Chang, Ting-Chang, E-mail: tcchang@mail.phys.nsysu.edu.tw [Department of Physics, National Sun Yat-Sen University, Kaohsiung 804, Taiwan (China); Advanced Optoelectronics Technology Center, National Cheng Kung University, Tainan, Taiwan (China); Lu, Ying-Hsin; Lo, Wen-Hung; Tsai, Jyun-Yu; Liu, Kuan-Ju [Department of Physics, National Sun Yat-Sen University, Kaohsiung 804, Taiwan (China); Wang, Bin-Wei; Cao, Xi-Xin [Department of Embedded System Engineering, Peking University, Beijing, P.R.China (China); Chen, Hua-Mao [Department of Photonics and Institute of Electro-Optical Engineering, National Chiao Tung University, Hsinchu, Taiwan (China); Cheng, Osbert; Huang, Cheng-Tung; Chen, Tsai-Fu [Device Department, United Microelectronics Corporation, Tainan Science Park, Taiwan (China)

    2013-11-07T23:59:59.000Z

    In this paper, we investigate the influence of falling time and base level time on high-k bulk shallow traps measured by charge pumping technique in n-channel metal-oxide-semiconductor field-effect transistors with HfO{sub 2}/metal gate stacks. N{sub T}-V{sub high} {sub level} characteristic curves with different duty ratios indicate that the electron detrapping time dominates the value of N{sub T} for extra contribution of I{sub cp} traps. N{sub T} is the number of traps, and I{sub cp} is charge pumping current. By fitting discharge formula at different temperatures, the results show that extra contribution of I{sub cp} traps at high voltage are in fact high-k bulk shallow traps. This is also verified through a comparison of different interlayer thicknesses and different Ti{sub x}N{sub 1?x} metal gate concentrations. Next, N{sub T}-V{sub high} {sub level} characteristic curves with different falling times (t{sub falling} {sub time}) and base level times (t{sub base} {sub level}) show that extra contribution of I{sub cp} traps decrease with an increase in t{sub falling} {sub time}. By fitting discharge formula for different t{sub falling} {sub time}, the results show that electrons trapped in high-k bulk shallow traps first discharge to the channel and then to source and drain during t{sub falling} {sub time}. This current cannot be measured by the charge pumping technique. Subsequent measurements of N{sub T} by charge pumping technique at t{sub base} {sub level} reveal a remainder of electrons trapped in high-k bulk shallow traps.

  7. Extended Coherence Time on the Clock Transition of Optically Trapped Rubidium

    SciTech Connect (OSTI)

    Kleine Buening, G.; Will, J.; Ertmer, W.; Rasel, E.; Klempt, C. [Institut fuer Quantenoptik, Leibniz Universitaet Hannover, Welfengarten 1, 30167 Hannover (Germany); Arlt, J. [QUANTOP, Institut for Fysik og Astronomi, Aarhus Universitet, Ny Munkegade 120, 8000 Aarhus C (Denmark); Ramirez-Martinez, F.; Rosenbusch, P. [LNE-SYRTE, Observatoire de Paris, CNRS, UPMC, 61 av de l'Observatoire, 75014 Paris (France); Piechon, F. [Laboratoire de Physique des Solides, CNRS, UMR 8502, Univ. Paris-Sud, 91405 Orsay (France)

    2011-06-17T23:59:59.000Z

    Optically trapped ensembles are of crucial importance for frequency measurements and quantum memories but generally suffer from strong dephasing due to inhomogeneous density and light shifts. We demonstrate a drastic increase of the coherence time to 21 s on the magnetic field insensitive clock transition of {sup 87}Rb by applying the recently discovered spin self-rephasing [C. Deutsch et al., Phys. Rev. Lett. 105, 020401 (2010)]. This result confirms the general nature of this new mechanism and thus shows its applicability in atom clocks and quantum memories. A systematic investigation of all relevant frequency shifts and noise contributions yields a stability of 2.4x10{sup -11{tau}-1/2}, where {tau} is the integration time in seconds. Based on a set of technical improvements, the presented frequency standard is predicted to rival the stability of microwave fountain clocks in a potentially much more compact setup.

  8. STOPPING TIMES IN QUANTUM MECHANICS

    E-Print Network [OSTI]

    Attal, Stéphane

    (Stinespring, Kraus). 3". Time-dependant case General time evolution of an open quantum sys- tem = (Pt)t0

  9. Quantum mechanical time contradicts the uncertainty principle

    E-Print Network [OSTI]

    Hitoshi Kitada

    1999-11-17T23:59:59.000Z

    The a priori time in conventional quantum mechanics is shown to contradict the uncertainty principle. A possible solution is given.

  10. Real-Time Virus Trapping and Fluorescent Imaging in Microfluidic

    E-Print Network [OSTI]

    Bashir, Rashid

    particles; however, this method requires the samples to be dried, fixed, coated, and laboriously prepared time, the images were collected with a computer running a video image capture

  11. Long-term Variations of CO2 Trapped in Different Mechanisms in Deep Saline Formations: A Case Study of the Songliao Basin, China

    SciTech Connect (OSTI)

    Zhang, Wei; Li, Yilian; Xu, Tianfu; Cheng, Huilin; Zheng, Yan; Xiong, Peng

    2008-06-10T23:59:59.000Z

    The geological storage of CO{sub 2} in deep saline formations is increasing seen as a viable strategy to reduce the release of greenhouse gases to the atmosphere. There are numerous sedimentary basins in China, in which a number of suitable CO{sub 2} geologic reservoirs are potentially available. To identify the multi-phase processes, geochemical changes and mineral alteration, and CO{sub 2} trapping mechanisms after CO{sub 2} injection, reactive geochemical transport simulations using a simple 2D model were performed. Mineralogical composition and water chemistry from a deep saline formation of Songliao Basin were used. Results indicate that different storage forms of CO{sub 2} vary with time. In the CO{sub 2} injection period, a large amount of CO{sub 2} remains as a free supercritical phase (gas trapping), and the amount dissolved in the formation water (solubility trapping) gradually increases. Later, gas trapping decreases, solubility trapping increases significantly due to migration and diffusion of the CO{sub 2} plume, and the amount trapped by carbonate minerals increases gradually with time. The residual CO{sub 2} gas keeps dissolving into groundwater and precipitating carbonate minerals. For the Songliao Basin sandstone, variations in the reaction rate and abundance of chlorite, and plagioclase composition affect significantly the estimates of mineral alteration and CO{sub 2} storage in different trapping mechanisms. The effect of vertical permeability and residual gas saturation on the overall storage is smaller compared to the geochemical factors. However, they can affect the spatial distribution of the injected CO{sub 2} in the formations. The CO{sub 2} mineral trapping capacity could be in the order of ten kilogram per cubic meter medium for the Songliao Basin sandstone, and may be higher depending on the composition of primary aluminosilicate minerals especially the content of Ca, Mg, and Fe.

  12. Time evolution of snow regions and planet traps in an evolving protoplanetary disk

    E-Print Network [OSTI]

    Baillié, Kévin; Pantin, Éric

    2015-01-01T23:59:59.000Z

    Aims. We track the time evolution of planet traps and snowlines in a viscously evolving protoplanetary disk using an opacity table that accounts for the composition of the dust material. Methods. We coupled a dynamical and thermodynamical disk model with a temperature-dependent opacity table (that accounts for the sublimation of the main dust components) to investigate the formation and evolution of snowlines and planet traps during the first million years of disk evolution. Results. Starting from a minimum mass solar nebula (MMSN), we find that the disk mid-plane temperature profile shows several plateaux (0.1-1 AU wide) at the different sublimation temperatures of the species that make up the dust. For water ice, the correspond- ing plateau can be larger than 1 AU, which means that this is a snow "region" rather than a snow "line". As a consequence, the surface density of solids in the snow region may increase gradually, not abruptly. Several planet traps and desert regions appear naturally as a result of a...

  13. Quantum mechanics and the time travel paradox

    E-Print Network [OSTI]

    David T. Pegg

    2005-06-17T23:59:59.000Z

    The closed causal chains arising from backward time travel do not lead to paradoxes if they are self consistent. This raises the question as to how physics ensures that only self-consistent loops are possible. We show that, for one particular case at least, the condition of self consistency is ensured by the interference of quantum mechanical amplitudes associated with the loop. If this can be applied to all loops then we have a mechanism by which inconsistent loops eliminate themselves.

  14. Quantum mechanics and the direction of time

    SciTech Connect (OSTI)

    Hasegawa, H.; Petrosky, T. (Univ. of Texas, Austin (United States)); Prigogine, I. (Univ. of Texas, Austin (United States) International Solvay Inst. for Physics and Chemistry, Brussels (Belgium)); Tasaki, S. (International Solvay Inst. for Physics and Chemistry, Brussels (Belgium))

    1991-03-01T23:59:59.000Z

    In recent papers the authors have discussed the dynamical properties of large Poincare systems (LPS), that is, nonintegrable systems with a continuous spectrum (both classical and quantum). An interesting example of LPS is given by the Friedrichs model of field theory. As is well known, perturbation methods analytic in the coupling constant diverge because of resonant denominators. They show that this Poincare catastrophe can be eliminated by a natural time ordering of the dynamical states. They obtain then a dynamical theory which incorporates a privileged direction of time (and therefore the second law of thermodynamics). However, it is only in very simple situations that his time ordering can be performed in an extended Hilbert space. In general, they need to go to the Liouville space (superspace) and introduce a time ordering of dynamical states according to the number of particles involved in correlations. This leads then to a generalization of quantum mechanics in which the usual Heisenberg's eigenvalue problem is replaced by a complex eigenvalue problem in the Liouville space.

  15. Influence of interlayer trapping and detrapping mechanisms on the electrical characterization of hafnium oxide/silicon nitride stacks on silicon

    SciTech Connect (OSTI)

    Garcia, H.; Duenas, S.; Castan, H.; Gomez, A.; Bailon, L. [Departamento de Electricidad y Electronica, E.T.S.I. Telecomunicacion, Universidad de Valladolid, Campus 'Miguel Delibes', 47011 Valladolid (Spain); Toledano-Luque, M.; Prado, A. del; Martil, I.; Gonzalez-Diaz, G. [Departamento de Fisica Aplicada III (Electricidad y Electronica), Facultad de Ciencias Fisicas, Universidad Complutense, 28040 Madrid (Spain)

    2008-11-01T23:59:59.000Z

    Al/HfO{sub 2}/SiN{sub x}:H/n-Si metal-insulator-semiconductor capacitors have been studied by electrical characterization. Films of silicon nitride were directly grown on n-type silicon substrates by electron cyclotron resonance assisted chemical vapor deposition. Silicon nitride thickness was varied from 3 to 6.6 nm. Afterwards, 12 nm thick hafnium oxide films were deposited by the high-pressure sputtering approach. Interface quality was determined by using current-voltage, capacitance-voltage, deep-level transient spectroscopy (DLTS), conductance transients, and flatband voltage transient techniques. Leakage currents followed the Poole-Frenkel emission model in all cases. According to the simultaneous measurement of the high and low frequency capacitance voltage curves, the interface trap density obtained for all the samples is in the 10{sup 11} cm{sup -2} eV{sup -1} range. However, a significant increase in this density of about two orders of magnitude was obtained by DLTS for the thinnest silicon nitride interfacial layers. In this work we probe that this increase is an artifact that must be attributed to traps existing at the HfO{sub 2}/SiN{sub x}:H intralayer interface. These traps are more easily charged or discharged as this interface comes near to the substrate, that is, as thinner the SiN{sub x}:H interface layer is. The trapping/detrapping mechanism increases the capacitance transient and, in consequence, the DLTS measurements have contributions not only from the insulator/substrate interface but also from the HfO{sub 2}/SiN{sub x}:H intralayer interface.

  16. Influence of Time-Varying External Magnetic Fields on Trapped Fields in Bulk Superconductors

    E-Print Network [OSTI]

    Zou, Jin; Ainslie, Mark D.; Hu, Di; Cardwell, David A.

    2014-12-12T23:59:59.000Z

    Large, single-grain bulk high-temperature superconductors (HTS) can trap magnetic fields over 17 T below 30 K and up to 3 T at 77 K, and have significant potential to replace permanent magnets, the fields from which are limited to significantly less...

  17. Unraveling the Timing of Fluid Migration and Trap Formation in the Brooks Range Foothills: A Key to Discovering Hydrocarbons

    SciTech Connect (OSTI)

    Catherine L. Hanks

    2008-12-31T23:59:59.000Z

    Naturally occurring fractures can play a key role in the evolution and producibility of a hydrocarbon accumulation. Understanding the evolution of fractures in the Brooks Range/Colville basin system of northern Alaska is critical to developing a better working model of the hydrocarbon potential of the region. This study addressed this problem by collecting detailed and regional data on fracture distribution and character, structural geometry, temperature, the timing of deformation along the Brooks Range rangefront and adjacent parts of the Colville basin, and the in situ stress distribution within the Colville basin. This new and existing data then were used to develop a model of how fractures evolved in northern Alaska, both spatially and temporally. The results of the study indicate that fractures formed episodically throughout the evolution of northern Alaska, due to a variety of mechanisms. Four distinct fracture sets were observed. The earliest fractures formed in deep parts of the Colville basin and in the underlying Ellesmerian sequence rocks as these rocks experienced compression associated with the growing Brooks Range fold-and-thrust belt. The orientation of these deep basin fractures was controlled by the maximum in situ horizontal stress in the basin at the time of their formation, which was perpendicular to the active Brooks Range thrust front. This orientation stayed consistently NS-striking for most of the early history of the Brooks Range and Colville basin, but changed to NW-striking with the development of the northeastern Brooks Range during the early Tertiary. Subsequent incorporation of these rocks into the fold-and-thrust belt resulted in overprinting of these deep basin fractures by fractures caused by thrusting and related folding. The youngest fractures developed as rocks were uplifted and exposed. While this general order of fracturing remains consistent across the Brooks Range and adjacent Colville basin, the absolute age at any one location varies. Fracturing started in the southwest deep in the stratigraphic section during the Late Jurassic and Early Cretaceous, moving northeastward and upsection as the Colville basin filled from the west. Active fracturing is occurring today in the northeastern parts of the Colville basin, north of the northeastern Brooks thrust front. Across northern Alaska, the early deep basin fractures were probably synchronous with hydrocarbon generation. Initially, these early fractures would have been good migration pathways, but would have been destroyed where subsequently overridden by the advancing Brooks Range fold-and-thrust belt. However, at these locations younger fracture sets related to folding and thrusting could have enhanced reservoir permeability and/or served as vertical migration pathways to overlying structural traps.

  18. Ion Funnel Trap Interface for Orthogonal Time-of-Flight Mass Spectrometry .

    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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFunInfrared LandResponses toInvestigatingAdaptedInvestor| EMSL Funnel Trap

  19. HP Steam Trap Monitoring

    E-Print Network [OSTI]

    Pascone, S.

    2011-01-01T23:59:59.000Z

    STEAM MONITORING HP Steam Trap Monitoring HP Steam Trap Monitoring ? 12-18 months payback! ? 3-5% permanent reduction in consumption ? LEED Pt.? Innovation in Operations EB O&M ? Saved clients over $1,000,000 Annual consumption... Steam Trap Monitoring ? Real-time monitoring for high-pressure critical traps (>15 PSIG) ? Average total system cost $25K - $50K ? Web-Based or Modbus/BMS Integration Basic Installation Wireless Signal Transmitter Receiver Repeater...

  20. Hydrocarbon trapping mechanisms in the Miller Creek area of the Powder River Basin, Wyoming

    E-Print Network [OSTI]

    Armstrong, Jennifer Ann

    1975-01-01T23:59:59.000Z

    '' 1975 43'W'79 ABSTRACT Hydrocarbon Trapoing Mechanisms in the Miller Creek Area of the Powder River Basin, Wyoming. (May 1975) Jennifer Ann Armstrong, B. S. , University of Texas at Austin Chairman of Advisory Committee: 17r. Robert. R. Berg...

  1. Feedback cooling of a single trapped ion

    E-Print Network [OSTI]

    Pavel Bushev; Daniel Rotter; Alex Wilson; Francois Dubin; Christoph Becher; Juergen Eschner; Rainer Blatt; Viktor Steixner; Peter Rabl; Peter Zoller

    2005-09-19T23:59:59.000Z

    Based on a real-time measurement of the motion of a single ion in a Paul trap, we demonstrate its electro-mechanical cooling below the Doppler limit by homodyne feedback control (cold damping). The feedback cooling results are well described by a model based on a quantum mechanical Master Equation.

  2. Long storage time of collective coherence in an optically trapped Bose-Einstein condensate Yutaka Yoshikawa,1,2,* Kazuyuki Nakayama,2

    E-Print Network [OSTI]

    Torii, Yoshio

    of condensates, a high conversion efficiency of over 70% and a long storage time of about 0.13 ms were achievedLong storage time of collective coherence in an optically trapped Bose-Einstein condensate Yutaka- Einstein condensate Phys. Rev. Lett. 99, 220407 2007 . This time we report the drastic improvement

  3. Trapping Coyotes

    E-Print Network [OSTI]

    Texas Wildlife Services

    2008-04-15T23:59:59.000Z

    to the carcass but well away from it (several hundred yards to a half mile or more). Traps Avarietyoftrapsareavailable.Cagetrapsare generallyineffective.Themosteffectivetrapsare the number three or four double spring leghold with offset jaws (see Fig. 2). Coil... spring traps no smaller than a number three should be set for coyotes. Stakes or drags must be attached to the traps to anchor the trapped coyote. Staking the trap is accomplishedbyattachingan18-inchironrodby a swivel to the trap spring or base with about...

  4. Generic Mechanism of Optimal Energy Transfer Efficiency: A Scaling Theory of the Mean First Passage Time in Exciton Systems

    E-Print Network [OSTI]

    Wu, Jianlan; Silbey, Robert J

    2013-01-01T23:59:59.000Z

    An asymptotic scaling theory is presented using the conceptual basis of trapping-free subspace (i.e., orthogonal subspace) to establish the generic mechanism of optimal efficiency of excitation energy transfer (EET) in light-harvesting systems. Analogous to Kramers' turnover in classical rate theory, the enhanced efficiency in the weak damping limit and the suppressed efficiency in the strong damping limit define two asymptotic scaling regimes, which are interpolated to predict the functional form of optimal efficiency of the trapping-free subspace. In the presence of static disorder, the scaling law of transfer time with respect to dephasing rate changes from linear to square root, suggesting a weaker dependence on the environment. Though formulated in the context of EET, the analysis and conclusions apply in general to open quantum processes, including electron transfer, fluorescence emission, and heat conduction.

  5. Generic Mechanism of Optimal Energy Transfer Efficiency: A Scaling Theory of the Mean First Passage Time in Exciton Systems

    E-Print Network [OSTI]

    Jianlan Wu; Jianshu Cao; Robert J. Silbey

    2012-07-26T23:59:59.000Z

    An asymptotic scaling theory is presented using the conceptual basis of trapping-free subspace (i.e., orthogonal subspace) to establish the generic mechanism of optimal efficiency of excitation energy transfer (EET) in light-harvesting systems. Analogous to Kramers' turnover in classical rate theory, the enhanced efficiency in the weak damping limit and the suppressed efficiency in the strong damping limit define two asymptotic scaling regimes, which are interpolated to predict the functional form of optimal efficiency of the trapping-free subspace. In the presence of static disorder, the scaling law of transfer time with respect to dephasing rate changes from linear to square root, suggesting a weaker dependence on the environment. Though formulated in the context of EET, the analysis and conclusions apply in general to open quantum processes, including electron transfer, fluorescence emission, and heat conduction.

  6. Nonlinear integrable ion traps

    SciTech Connect (OSTI)

    Nagaitsev, S.; /Fermilab; Danilov, V.; /SNS Project, Oak Ridge

    2011-10-01T23:59:59.000Z

    Quadrupole ion traps can be transformed into nonlinear traps with integrable motion by adding special electrostatic potentials. This can be done with both stationary potentials (electrostatic plus a uniform magnetic field) and with time-dependent electric potentials. These potentials are chosen such that the single particle Hamilton-Jacobi equations of motion are separable in some coordinate systems. The electrostatic potentials have several free adjustable parameters allowing for a quadrupole trap to be transformed into, for example, a double-well or a toroidal-well system. The particle motion remains regular, non-chaotic, integrable in quadratures, and stable for a wide range of parameters. We present two examples of how to realize such a system in case of a time-independent (the Penning trap) as well as a time-dependent (the Paul trap) configuration.

  7. Quantum Mechanics and Discrete Time from "Timeless" Classical Dynamics

    E-Print Network [OSTI]

    H. -T. Elze

    2003-07-03T23:59:59.000Z

    We study classical Hamiltonian systems in which the intrinsic proper time evolution parameter is related through a probability distribution to the physical time, which is assumed to be discrete. - This is motivated by the ``timeless'' reparametrization invariant model of a relativistic particle with two compactified extradimensions. In this example, discrete physical time is constructed based on quasi-local observables. - Generally, employing the path-integral formulation of classical mechanics developed by Gozzi et al., we show that these deterministic classical systems can be naturally described as unitary quantum mechanical models. The emergent quantum Hamiltonian is derived from the underlying classical one. It is closely related to the Liouville operator. We demonstrate in several examples the necessity of regularization, in order to arrive at quantum models with bounded spectrum and stable groundstate.

  8. Collisionless Weibel shocks: Full formation mechanism and timing

    SciTech Connect (OSTI)

    Bret, A. [ETSI Industriales, Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain); Instituto de Investigaciones Energéticas y Aplicaciones Industriales, Campus Universitario de Ciudad Real, 13071 Ciudad Real (Spain); Stockem, A. [GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Lisbon (Portugal); Institut für Theoretische Physik, Lehrstuhl IV: Weltraum- und Astrophysik, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Narayan, R. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-51 Cambridge, Massachusetts 02138 (United States); Silva, L. O. [GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Lisbon (Portugal)

    2014-07-15T23:59:59.000Z

    Collisionless shocks in plasmas play an important role in space physics (Earth's bow shock) and astrophysics (supernova remnants, relativistic jets, gamma-ray bursts, high energy cosmic rays). While the formation of a fluid shock through the steepening of a large amplitude sound wave has been understood for long, there is currently no detailed picture of the mechanism responsible for the formation of a collisionless shock. We unravel the physical mechanism at work and show that an electromagnetic Weibel shock always forms when two relativistic collisionless, initially unmagnetized, plasma shells encounter. The predicted shock formation time is in good agreement with 2D and 3D particle-in-cell simulations of counterstreaming pair plasmas. By predicting the shock formation time, experimental setups aiming at producing such shocks can be optimised to favourable conditions.

  9. Effect of trapped electron on the dust ion acoustic waves in dusty plasma using time fractional modified Korteweg-de Vries equation

    SciTech Connect (OSTI)

    Nazari-Golshan, A. [Department of Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of)] [Department of Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Nourazar, S. S. [Department of Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of) [Department of Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Department of Mechanical Engineering, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of)

    2013-10-15T23:59:59.000Z

    The time fractional modified Korteweg-de Vries (TFMKdV) equation is solved to study the nonlinear propagation of small but finite amplitude dust ion-acoustic (DIA) solitary waves in un-magnetized dusty plasma with trapped electrons. The plasma is composed of a cold ion fluid, stationary dust grains, and hot electrons obeying a trapped electron distribution. The TFMKdV equation is derived by using the semi-inverse and Agrawal's methods and then solved by the Laplace Adomian decomposition method. Our results show that the amplitude of the DIA solitary waves increases with the increase of time fractional order ?, the wave velocity v{sub 0}, and the population of the background free electrons ?. However, it is vice-versa for the deviation from isothermality parameter b, which is in agreement with the result obtained previously.

  10. Attonewton force detection using microspheres in a dual-beam optical trap in high vacuum

    E-Print Network [OSTI]

    Gambhir Ranjit; David P. Atherton; Jordan H. Stutz; Mark Cunningham; Andrew A. Geraci

    2015-04-03T23:59:59.000Z

    We describe the implementation of laser-cooled silica microspheres as force sensors in a dual-beam optical dipole trap in high vacuum. Using this system we have demonstrated trap lifetimes exceeding several days, attonewton force detection capability, and wide tunability in trapping and cooling parameters. Measurements have been performed with charged and neutral beads to calibrate the sensitivity of the detector. This work establishes the suitability of dual beam optical dipole traps for precision force measurement in high vacuum with long averaging times, and enables future applications including the study of gravitational inverse square law violations at short range, Casimir forces, acceleration sensing, and quantum opto-mechanics.

  11. Attonewton force detection using microspheres in a dual-beam optical trap in high vacuum

    E-Print Network [OSTI]

    Ranjit, Gambhir; Stutz, Jordan H; Cunningham, Mark; Geraci, Andrew A

    2015-01-01T23:59:59.000Z

    We describe the implementation of laser-cooled silica microspheres as force sensors in a dual-beam optical dipole trap in high vacuum. Using this system we have demonstrated trap lifetimes exceeding several days, attonewton force detection capability, and wide tunability in trapping and cooling parameters. Measurements have been performed with charged and neutral beads to calibrate the sensitivity of the detector. This work establishes the suitability of dual beam optical dipole traps for precision force measurement in high vacuum with long averaging times, and enables future applications including the study of gravitational inverse square law violations at short range, Casimir forces, acceleration sensing, and quantum opto-mechanics.

  12. Attonewton force detection using microspheres in a dual-beam optical trap in high vacuum

    E-Print Network [OSTI]

    Gambhir Ranjit; David P. Atherton; Jordan H. Stutz; Mark Cunningham; Andrew A. Geraci

    2015-03-30T23:59:59.000Z

    We describe the implementation of laser-cooled silica microspheres as force sensors in a dual-beam optical dipole trap in high vacuum. Using this system we have demonstrated trap lifetimes exceeding several days, attonewton force detection capability, and wide tunability in trapping and cooling parameters. Measurements have been performed with charged and neutral beads to calibrate the sensitivity of the detector. This work establishes the suitability of dual beam optical dipole traps for precision force measurement in high vacuum with long averaging times, and enables future applications including the study of gravitational inverse square law violations at short range, Casimir forces, acceleration sensing, and quantum opto-mechanics.

  13. Real-time Health Monitoring of Mechanical Structures

    E-Print Network [OSTI]

    Ray, Asok

    , years for bridges and roads, and number of starts for diesel engines. It is also assumed that the state of damage in a mechanical structure bears a direct correlation with the amount of usage. However, one

  14. Mechanism(s) of Ni Sorption on Al-Hydroxy-Interlayered Vermiculite Using Time-Resolved EXAFS

    E-Print Network [OSTI]

    Sparks, Donald L.

    Mechanism(s) of Ni Sorption on Al-Hydroxy-Interlayered Vermiculite Using Time-Resolved EXAFS D. R and the chemistry of soil clay minerals. In many weathered soils an abundance of Al-hydroxy-interlayered vermiculite (HIV) is present in the clay-size fraction. The Al in the interlayers is potentially quite reactive

  15. Highlighting the mechanism of the quantum speedup by time-symmetric and relational quantum mechanics

    E-Print Network [OSTI]

    Giuseppe Castagnoli

    2014-12-11T23:59:59.000Z

    Bob hides a ball in one of four drawers. Alice is to locate it. Classically she has to open up to three drawers, quantally just one. The fundamental reason for this quantum speedup is not known. We explain it by extending the usual representation of the quantum algorithm, limited to the process of solving the problem, to the process of setting the problem. The number of the drawer with the ball becomes a unitary transformation of the random outcome of the preparation measurement. This brings in relational quantum mechanics: the extension is with respect to Bob and cannot be with respect to Alice. It would tell her the drawer number before she opens any drawer. To Alice, the projection of the quantum state due to the preparation measurement should be retarded at the end of her search; in the input state of the search, the drawer number is determined to Bob and undetermined to Alice. A second consequence is the emergence of an ambiguity. Either the preparation measurement or the final one required to read the solution selects the solution. For reasons of symmetry, we assume that the selection shares evenly between the two measurements. All is as if Alice, by reading the solution, selected half of the information that specifies the drawer number. This selection leaves the input state to Bob unaltered and projects that to Alice on a state of lower entropy where she knows that half in advance. The quantum algorithm is a sum over histories in each of which Alice knows in advance that the ball is in a pair of drawers and locates it by opening one of the two. More in general, given an oracle problem, this explanation of the speedup predicts the number of queries required to solve it in an optimal quantum way.

  16. Reduce Steam Trap Failures at Chambers Works

    E-Print Network [OSTI]

    Kouba, C.

    Ultrasonic Inspection At least 2 times per year Steam Trap Surveyor Submit reports to area management, energy team, and reliability engineers for each area every month Steam Trap Team Leader Control Plan ? Process Owner agrees...Reduce Steam Trap Failures at Chambers Works GB/BB Name: Cyndi Kouba Mentor/MBB: Andrew Degraff Team Members Michael Crowley(Site Energy Lead), (Charlie) Flanigan (Aramids-maintenance), Ben Snyder (Aramids-ATO), Michael Scruggs (Central...

  17. Trapped-ion Lissajous trajectories

    E-Print Network [OSTI]

    R. F. Rossetti; G. D. de Moraes Neto; J. Carlos Egues; M. H. Y. Moussa

    2015-02-25T23:59:59.000Z

    Here we present a protocol for generating Lissajous curves with a trapped ion by engineering Rashba- and the Dresselhaus-type spin-orbit interactions in a Paul trap. The unique anisotropic Rashba $\\alpha_{x}$, $\\alpha_{y}$ and Dresselhaus $\\beta_{x}$, $\\beta_{y}$ couplings afforded by our setup also enables us to obtain an "unusual" Zitterbewegung, i.e., the semiconductor analog of the relativistic trembling motion of electrons, with cycloidal trajectories in the absence of magnetic fields. We have also introduced bounded SO interactions, confined to an upper-bound vibrational subspace of the Fock states, as an additional mechanism to manipulate the Lissajous motion of the trapped ion. Finally, we accounted for dissipative effects on the vibrational degrees of freedom of the ion and find that the Lissajous trajectories are still robust and well defined for realistic parameters.

  18. Microfabricated Ion Traps

    E-Print Network [OSTI]

    Marcus D. Hughes; Bjoern Lekitsch; Jiddu A. Broersma; Winfried K. Hensinger

    2011-06-28T23:59:59.000Z

    Ion traps offer the opportunity to study fundamental quantum systems with high level of accuracy highly decoupled from the environment. Individual atomic ions can be controlled and manipulated with electric fields, cooled to the ground state of motion with laser cooling and coherently manipulated using optical and microwave radiation. Microfabricated ion traps hold the advantage of allowing for smaller trap dimensions and better scalability towards large ion trap arrays also making them a vital ingredient for next generation quantum technologies. Here we provide an introduction into the principles and operation of microfabricated ion traps. We show an overview of material and electrical considerations which are vital for the design of such trap structures. We provide guidance in how to choose the appropriate fabrication design, consider different methods for the fabrication of microfabricated ion traps and discuss previously realized structures. We also discuss the phenomenon of anomalous heating of ions within ion traps, which becomes an important factor in the miniaturization of ion traps.

  19. Schwinger Mechanism for Fermion Pair Production in the Presence of Arbitrary Time Dependent Background Electric Field

    E-Print Network [OSTI]

    Fred Cooper; Gouranga C. Nayak

    2006-12-29T23:59:59.000Z

    We study the Schwinger mechanism for the pair production of fermions in the presence of an arbitrary time-dependent background electric field E(t) by directly evaluating the path integral. We obtain an exact non-perturbative result for the probability of fermion-antifermion pair production per unit time per unit volume per unit transverse momentum (of the fermion or antifermion) from the arbitrary time dependent electric field E(t) via Schwinger mechanism. We find that the exact non-perturbative result is independent of all the time derivatives d^nE(t)/dt^n, where n=1,2,....\\infty. This result has the same functional dependence on E as the Schwinger's constant electric field E result with the replacement: E -> E(t).

  20. Superconducting microfabricated ion traps

    E-Print Network [OSTI]

    Wang, Shannon Xuanyue

    We fabricate superconducting ion traps with niobium and niobium nitride and trap single [superscript 88]Sr ions at cryogenic temperatures. The superconducting transition is verified and characterized by measuring the ...

  1. REVIEW ARTICLE Optical trapping

    E-Print Network [OSTI]

    Block, Steven

    REVIEW ARTICLE Optical trapping Keir C. Neuman and Steven M. Blocka) Department of Biological ago, optical traps have emerged as a powerful tool with broad-reaching applications in biology--and the measurement of nanometer-level displacements of--optically trapped objects. We review progress

  2. Standard Model tests with trapped radioactive atoms

    E-Print Network [OSTI]

    J. A. Behr; G. Gwinner

    2009-03-04T23:59:59.000Z

    We review the use of laser cooling and trapping for Standard Model tests, focusing on trapping of radioactive isotopes. Experiments with neutral atoms trapped with modern laser cooling techniques are testing several basic predictions of electroweak unification. For nuclear $\\beta$ decay, demonstrated trap techniques include neutrino momentum measurements from beta-recoil coincidences, along with methods to produce highly polarized samples. These techniques have set the best general constraints on non-Standard Model scalar interactions in the first generation of particles. They also have the promise to test whether parity symmetry is maximally violated, to search for tensor interactions, and to search for new sources of time reversal violation. There are also possibilites for exotic particle searches. Measurements of the strength of the weak neutral current can be assisted by precision atomic experiments using traps of small numbers of radioactive atoms, and sensitivity to possible time-reversal violating electric dipole moments can be improved.

  3. Superconducting microfabricated ion traps

    E-Print Network [OSTI]

    Shannon X. Wang; Yufei Ge; Jaroslaw Labaziewicz; Eric Dauler; Karl Berggren; Isaac L. Chuang

    2010-12-14T23:59:59.000Z

    We fabricate superconducting ion traps with niobium and niobium nitride and trap single 88Sr ions at cryogenic temperatures. The superconducting transition is verified and characterized by measuring the resistance and critical current using a 4-wire measurement on the trap structure, and observing change in the rf reflection. The lowest observed heating rate is 2.1(3) quanta/sec at 800 kHz at 6 K and shows no significant change across the superconducting transition, suggesting that anomalous heating is primarily caused by noise sources on the surface. This demonstration of superconducting ion traps opens up possibilities for integrating trapped ions and molecular ions with superconducting devices.

  4. Fast ground-state cooling of mechanical resonators with time-dependent optical cavities

    SciTech Connect (OSTI)

    Li Yong [Department of Physics and Center of Theoretical and Computational Physics, University of Hong Kong, Pokfulam Road (Hong Kong); Beijing Computational Science Research Center, Beijing 100084 (China); Wu Lianao [Department of Theoretical Physics and History of Science, The Basque Country University (EHU/UPV), P.O. Box 644, ES-48080 Bilbao (Spain); IKERBASQUE, Basque Foundation for Science, ES-48011 Bilbao (Spain); Wang, Z. D. [Department of Physics and Center of Theoretical and Computational Physics, University of Hong Kong, Pokfulam Road (Hong Kong)

    2011-04-15T23:59:59.000Z

    We propose a feasible scheme to cool down a mechanical resonator (MR) in a three-mirror cavity optomechanical system with controllable external optical driving fields. Under the Born-Oppenheimer approximation, the whole dynamics of the mechanical resonator and cavities is reduced to that of a time-dependent harmonic oscillator, whose effective frequency can be controlled through the optical driving fields. The fast cooling of the MR can be realized by controlling the amplitude of the optical driving fields. Significantly, we further show that the ground-state cooling may be achieved via the three-mirror cavity optomechanical system without the resolved sideband condition.

  5. Laser trapping of {sup 21}Na atoms

    SciTech Connect (OSTI)

    Lu, Zheng-Tian

    1994-09-01T23:59:59.000Z

    This thesis describes an experiment in which about four thousand radioactive {sup 21}Na (t{sub l/2} = 22 sec) atoms were trapped in a magneto-optical trap with laser beams. Trapped {sup 21}Na atoms can be used as a beta source in a precision measurement of the beta-asymmetry parameter of the decay of {sup 21}Na {yields} {sup 21}Ne + {Beta}{sup +} + v{sub e}, which is a promising way to search for an anomalous right-handed current coupling in charged weak interactions. Although the number o trapped atoms that we have achieved is still about two orders of magnitude lower than what is needed to conduct a measurement of the beta-asymmetry parameter at 1% of precision level, the result of this experiment proved the feasibility of trapping short-lived radioactive atoms. In this experiment, {sup 21}Na atoms were produced by bombarding {sup 24}Mg with protons of 25 MeV at the 88 in. Cyclotron of Lawrence Berkeley Laboratory. A few recently developed techniques of laser manipulation of neutral atoms were applied in this experiment. The {sup 21}Na atoms emerging from a heated oven were first transversely cooled. As a result, the on-axis atomic beam intensity was increased by a factor of 16. The atoms in the beam were then slowed down from thermal speed by applying Zeeman-tuned slowing technique, and subsequently loaded into a magneto-optical trap at the end of the slowing path. The last two chapters of this thesis present two studies on the magneto-optical trap of sodium atoms. In particular, the mechanisms of magneto-optical traps at various laser frequencies and the collisional loss mechanisms of these traps were examined.

  6. GRANIT project: a trap for gravitational quantum states of UCN

    E-Print Network [OSTI]

    Pignol, G; Rebreyend, D; Vezzu, F; Nesvizhevsky, V V; Petukhov, A K; Börner, H G; Soldner, T; Schmidt-Wellenburg, P; Kreuz, M; Forest, D; Ganau, P; Mackowski, J M; Michel, C; Montorio, J L; Morgado, N; Pinard, L; Remillieux, A; Gagarski, A M; Petrov, G A; Kusmina, A M; Strelkov, A V; Abele, H; Baeßler, S; Voronin, A Yu

    2007-01-01T23:59:59.000Z

    Previous studies of gravitationally bound states of ultracold neutrons showed the quantization of energy levels, and confirmed quantum mechanical predictions for the average size of the two lowest energy states wave functions. Improvements in position-like measurements can increase the accuracy by an order of magnitude only. We therefore develop another approach, consisting in accurate measurements of the energy levels. The GRANIT experiment is devoted to the study of resonant transitions between quantum states induced by an oscillating perturbation. According to Heisenberg's uncertainty relations, the accuracy of measurement of the energy levels is limited by the time available to perform the transitions. Thus, trapping quantum states will be necessary, and each source of losses has to be controlled in order to maximize the lifetime of the states. We discuss the general principles of transitions between quantum states, and consider the main systematical losses of neutrons in a trap.

  7. GRANIT project: a trap for gravitational quantum states of UCN

    E-Print Network [OSTI]

    G. Pignol; K. V. Protasov; D. Rebreyend; F. Vezzu; V. V. Nesvizhevsky; A. K. Petukhov; H. G. Börner; T. Soldner; P. Schmidt-Wellenburg; M. Kreuz; D. Forest; P. Ganau; J. M. Mackowski; C. Michel; J. L. Montorio; N. Morgado; L. Pinard; A. Remillieux; A. M. Gagarski; G. A. Petrov; A. M. Kusmina; A. V. Strelkov; H. Abele; S. Baeßler; A. Yu. Voronin

    2007-08-19T23:59:59.000Z

    Previous studies of gravitationally bound states of ultracold neutrons showed the quantization of energy levels, and confirmed quantum mechanical predictions for the average size of the two lowest energy states wave functions. Improvements in position-like measurements can increase the accuracy by an order of magnitude only. We therefore develop another approach, consisting in accurate measurements of the energy levels. The GRANIT experiment is devoted to the study of resonant transitions between quantum states induced by an oscillating perturbation. According to Heisenberg's uncertainty relations, the accuracy of measurement of the energy levels is limited by the time available to perform the transitions. Thus, trapping quantum states will be necessary, and each source of losses has to be controlled in order to maximize the lifetime of the states. We discuss the general principles of transitions between quantum states, and consider the main systematical losses of neutrons in a trap.

  8. Microfabricated ion trap array

    DOE Patents [OSTI]

    Blain, Matthew G. (Albuquerque, NM); Fleming, James G. (Albuquerque, NM)

    2006-12-26T23:59:59.000Z

    A microfabricated ion trap array, comprising a plurality of ion traps having an inner radius of order one micron, can be fabricated using surface micromachining techniques and materials known to the integrated circuits manufacturing and microelectromechanical systems industries. Micromachining methods enable batch fabrication, reduced manufacturing costs, dimensional and positional precision, and monolithic integration of massive arrays of ion traps with microscale ion generation and detection devices. Massive arraying enables the microscale ion traps to retain the resolution, sensitivity, and mass range advantages necessary for high chemical selectivity. The reduced electrode voltage enables integration of the microfabricated ion trap array with on-chip circuit-based rf operation and detection electronics (i.e., cell phone electronics). Therefore, the full performance advantages of the microfabricated ion trap array can be realized in truly field portable, handheld microanalysis systems.

  9. Neutral atom traps.

    SciTech Connect (OSTI)

    Pack, Michael Vern

    2008-12-01T23:59:59.000Z

    This report describes progress in designing a neutral atom trap capable of trapping sub millikelvin atom in a magnetic trap and shuttling the atoms across the atom chip from a collection area to an optical cavity. The numerical simulation and atom chip design are discussed. Also, discussed are preliminary calculations of quantum noise sources in Kerr nonlinear optics measurements based on electromagnetically induced transparency. These types of measurements may be important for quantum nondemolition measurements at the few photon limit.

  10. From Discrete Space-Time to Minkowski Space: Basic Mechanisms, Methods and Perspectives

    E-Print Network [OSTI]

    Felix Finster

    2008-02-22T23:59:59.000Z

    This survey article reviews recent results on fermion system in discrete space-time and corresponding systems in Minkowski space. After a basic introduction to the discrete setting, we explain a mechanism of spontaneous symmetry breaking which leads to the emergence of a discrete causal structure. As methods to study the transition between discrete space-time and Minkowski space, we describe a lattice model for a static and isotropic space-time, outline the analysis of regularization tails of vacuum Dirac sea configurations, and introduce a Lorentz invariant action for the masses of the Dirac seas. We mention the method of the continuum limit, which allows to analyze interacting systems. Open problems are discussed.

  11. Structural traps I, tectonic fold traps

    SciTech Connect (OSTI)

    Beaumont, E.A.; Foster, N.H.

    1990-01-01T23:59:59.000Z

    This book contains studies of fields that exist because of the presence of an anticline; without the anticline there would be no trap. The fields described in this volume illustrate the complex nature of a trap type that some explorationists mistakenly regard as simple and therefore not worthy of close scrutiny. Anticlinal traps are like all other fields - each has its own peculiar personality. Many of the fields in this volume are sourced from continentally derived organic matter. All have sandstone reservoirs. Most have shale seals, but one, Sarir, has an evaporite seal. Many are faulted anticlines. Some of the anticlines formed in a compressional tectonic setting, whereas others formed in a tensional tectonic setting.

  12. Neutron-Mirror-Neutron Oscillations in a Trap

    E-Print Network [OSTI]

    B. Kerbikov; O. Lychkovskiy

    2008-04-03T23:59:59.000Z

    We calculate the rate of neutron-mirror-neutron oscillations for ultracold neutrons trapped in a storage vessel. Recent experimental bounds on the oscillation time are discussed.

  13. Chemical dynamics in the gas phase: Time-dependent quantum mechanics of chemical reactions

    SciTech Connect (OSTI)

    Gray, S.K. [Argonne National Laboratory, IL (United States)

    1993-12-01T23:59:59.000Z

    A major goal of this research is to obtain an understanding of the molecular reaction dynamics of three and four atom chemical reactions using numerically accurate quantum dynamics. This work involves: (i) the development and/or improvement of accurate quantum mechanical methods for the calculation and analysis of the properties of chemical reactions (e.g., rate constants and product distributions), and (ii) the determination of accurate dynamical results for selected chemical systems, which allow one to compare directly with experiment, determine the reliability of the underlying potential energy surfaces, and test the validity of approximate theories. This research emphasizes the use of recently developed time-dependent quantum mechanical methods, i.e. wave packet methods.

  14. Time Synchronization Attack in Smart Grid-Part II: Cross Layer Detection Mechanism

    E-Print Network [OSTI]

    Zhang, Zhenghao; Dimitrovski, Aleksandar D; Li, Husheng

    2012-01-01T23:59:59.000Z

    A novel time synchronization attack (TSA) on wide area monitoring systems in smart grid has been identified in the first part of this paper. A cross layer detection mechanism is proposed to combat TSA in part II of this paper. In the physical layer, we propose a GPS carrier signal noise ratio (C/No) based spoofing detection technique. In addition, a patch-monopole hybrid antenna is applied to receive GPS signal. By computing the standard deviation of the C/No difference from two GPS receivers, a priori probability of spoofing detection is fed to the upper layer, where power system state is estimated and controlled. A trustworthiness based evaluation method is applied to identify the PMU being under TSA. Both the physical layer and upper layer algorithms are integrated to detect the TSA, thus forming a cross layer mechanism. Experiment is carried out to verify the effectiveness of the proposed TSA detection algorithm.

  15. Steam Trap Management

    E-Print Network [OSTI]

    Murphy, J. J.; Hirtner, H. H.

    A medium-sized plant of a high technology company is reaping the benefits of a Pro-active Steam Trap Program provided by Yarway's TECH/SERV Division. Initial work began March '84 and the most recent steam trap feasibility study conducted in March...

  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?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. Surface trap for ytterbium ions

    E-Print Network [OSTI]

    Campbell, Jonathan A. (Jonathan Alan)

    2006-01-01T23:59:59.000Z

    We conducted an experiment to load a shallow planar ion trap from a cold atom source of Ytterbium using photoionization. The surface trap consisted of a three-rod radio frequency Paul trap fabricated using standard printed ...

  18. Inertial measurement with trapped particles: A microdynamical system

    SciTech Connect (OSTI)

    Post, E. Rehmi; Popescu, George A.; Gershenfeld, Neil [Center for Bits and Atoms, Massachusetts Institute of Technology, 20 Ames Street, Cambridge, Massachusetts 02139 (United States)

    2010-04-05T23:59:59.000Z

    We describe an inertial measurement device based on an electrodynamically trapped proof mass. Mechanical constraints are replaced by guiding fields, permitting the trap stiffness to be tuned dynamically. Optical readout of the proof mass motion provides a measurement of acceleration and rotation, resulting in an integrated six degree of freedom inertial measurement device. We demonstrate such a device - constructed without microfabrication - with sensitivity comparable to that of commercial microelectromechanical systems technology and show how trapping parameters may be adjusted to increase dynamic range.

  19. Heating of trapped ultracold atoms by collapse dynamics

    E-Print Network [OSTI]

    Franck Laloë; William J. Mullin; Philip Pearle

    2014-11-12T23:59:59.000Z

    {The Continuous Spontaneous Localization (CSL) theory alters the Schr\\"odinger equation. It describes wave function collapse as a dynamical process instead of an ill-defined postulate, thereby providing macroscopic uniqueness and solving the so-called measurement problem of standard quantum theory. CSL contains a parameter $\\lambda$ giving the collapse rate of an isolated nucleon in a superposition of two spatially separated states and, more generally, characterizing the collapse time for any physical situation. CSL is experimentally testable, since it predicts some behavior different from that predicted by standard quantum theory. One example is the narrowing of wave functions, which results in energy imparted to particles. Here we consider energy given to trapped ultra-cold atoms. Since these are the coldest samples under experimental investigation, it is worth inquiring how they are affected by the CSL heating mechanism. We examine the CSL heating of a BEC in contact with its thermal cloud. Of course, other mechanisms also provide heat and also particle loss. From varied data on optically trapped cesium BEC's, we present an energy audit for known heating and loss mechanisms. The result provides an upper limit on CSL heating and thereby an upper limit on the parameter $\\lambda$. We obtain $\\lambda\\lesssim 1(\\pm1)\\times 10^{-7}$sec$^{-1}$.}

  20. Evaluating Steam Trap Performance

    E-Print Network [OSTI]

    Fuller, N. Y.

    ~LmT " TRIf' 1 TRIf' 2 Figure 2 It has become common practice for engineers to oversize steam traps and place more emphasis on first cost than on maintenance cost and operating 766 3 4 ESL-IE-86-06-126 Proceedings from the Eighth Annual Industrial...EVALUATING STEAM TRAP PERFORMANCE Noel Y Fuller, P.E. Holston Defense Corporation Kingsport, Tennessee ABSTRACT Laboratory tests were conducted on several types of steam traps at Holston Defense Corporation in Kingsport, Tennessee. Data...

  1. Transport of hydrogen in metals with occupancy dependent trap energies

    SciTech Connect (OSTI)

    Schmid, K., E-mail: klaus.schmid@ipp.mpg.de; Toussaint, U. von; Schwarz-Selinger, T. [Max-Planck-Institut für Plasmaphysik, Boltzmannstraße 2, D-85748 Garching b. München (Germany)

    2014-10-07T23:59:59.000Z

    Common diffusion trapping models for modeling hydrogen transport in metals are limited to traps with single de-trapping energies and a saturation occupancy of one. While they are successful in predicting typical mono isotopic ion implantation and thermal degassing experiments, they fail at describing recent experiments on isotope exchange at low temperatures. This paper presents a new modified diffusion trapping model with fill level dependent de-trapping energies that can also explain these new isotope exchange experiments. Density function theory (DFT) calculations predict that even mono vacancies can store between 6 and 12?H atoms with de-trapping energies that depend on the fill level of the mono vacancy. The new fill level dependent diffusion trapping model allows to test these DFT results by bridging the gap in length and time scale between DFT calculations and experiment.

  2. System and method for trapping and measuring a charged particle in a liquid

    DOE Patents [OSTI]

    Reed, Mark A; Krstic, Predrag S; Guan, Weihua; Zhao, Xiongce

    2013-07-23T23:59:59.000Z

    A system and method for trapping a charged particle is disclosed. A time-varying periodic multipole electric potential is generated in a trapping volume. A charged particle under the influence of the multipole electric field is confined to the trapping volume. A three electrode configuration giving rise to a 3D Paul trap and a four planar electrode configuration giving rise to a 2D Paul trap are disclosed.

  3. Steam trap monitor

    DOE Patents [OSTI]

    Ryan, M.J.

    1987-05-04T23:59:59.000Z

    A steam trap monitor positioned downstream of a steam trap in a closed steam system includes a first sensor (a hot finger) for measuring the energy of condensate and a second sensor (a cold finger) for measuring the total energy of condensate and steam in the line. The hot finger includes one or more thermocouples for detecting condensate level and energy, while the cold finger contains a liquid with a lower boiling temperature than that of water. Vapor pressure from the liquid is used to do work such as displacing a piston or bellow in providing an indication of total energy (steam + condensate) of the system. Processing means coupled to and responsive to outputs from the hot and cold fingers subtracts the former from the latter to provide an indication of the presence of steam downstream from the trap indicating that the steam trap is malfunctioning. 2 figs.

  4. Mechanisms for the convergence of time-parallelized, parareal turbulent plasma simulations

    SciTech Connect (OSTI)

    Reynolds-Barredo, J. [University of Alaska; University Carlos III de Madrid; Newman, David E [University of Alaska; Sanchez, R. [Universidad Carlos III, Madrid, Spain; Samaddar, D. [ITER Organization, Saint Paul Lez Durance, France; Berry, Lee A [ORNL; Elwasif, Wael R [ORNL

    2012-01-01T23:59:59.000Z

    Parareal is a recent algorithm able to parallelize the time dimension in spite of its sequential nature. It has been applied to several linear and nonlinear problems and, very recently, to a simulation of fully-developed, two-dimensional drift wave turbulence. The mere fact that parareal works in such a turbulent regime is in itself somewhat unexpected, due to the characteristic sensitivity of turbulence to any change in initial conditions. This fundamental property of any turbulent system should render the iterative correction procedure characteristic of the parareal method inoperative, but this seems not to be the case. In addition, the choices that must be made to implement parareal (division of the temporal domain, election of the coarse solver and so on) are currently made using trial-and-error approaches. Here, we identify the mechanisms responsible for the convergence of parareal of these simulations of drift wave turbulence. We also investigate which conditions these mechanisms impose on any successful parareal implementation. The results reported here should be useful to guide future implementations of parareal within the much wider context of fully-developed fluid and plasma turbulent simulations.

  5. Structural traps 5

    SciTech Connect (OSTI)

    Foster, N.H.; Beaumont, E.A.

    1991-01-01T23:59:59.000Z

    This book contains studies of oil and gas fields that are mainly structural in nature. Stratigraphy controls the extend of the reservoir in the traps of several fields, but overall, the main trapping features within the group of fields in this volume are structural. Fields covered in this volume include: Endicott Field, Point Arguello Field, West Puerto Chiquito Field, Dukhan Field, Sendji Field, Ruston Field, Raudhatain Field, Hassi Messaoud Field, Snapper Field, Tirrawarra Field, and Sacha Field.

  6. Microfabricated cylindrical ion trap

    SciTech Connect (OSTI)

    Blain, Matthew G.

    2005-03-22T23:59:59.000Z

    A microscale cylindrical ion trap, having an inner radius of order one micron, can be fabricated using surface micromachining techniques and materials known to the integrated circuits manufacturing and microelectromechanical systems industries. Micromachining methods enable batch fabrication, reduced manufacturing costs, dimensional and positional precision, and monolithic integration of massive arrays of ion traps with microscale ion generation and detection devices. Massive arraying enables the microscale cylindrical ion trap to retain the resolution, sensitivity, and mass range advantages necessary for high chemical selectivity. The microscale CIT has a reduced ion mean free path, allowing operation at higher pressures with less expensive and less bulky vacuum pumping system, and with lower battery power than conventional- and miniature-sized ion traps. The reduced electrode voltage enables integration of the microscale cylindrical ion trap with on-chip integrated circuit-based rf operation and detection electronics (i.e., cell phone electronics). Therefore, the full performance advantages of microscale cylindrical ion traps can be realized in truly field portable, handheld microanalysis systems.

  7. Structural traps 2

    SciTech Connect (OSTI)

    Beaumont, E.A.; Foster, N.H.

    1990-01-01T23:59:59.000Z

    This book contains studies of fields that exist because of the presence of tectonic faulting. Tectonic faulting occurs because of the release of crustal stresses. Nontectonic faulting is due to other factors, such as salt solution and collapse or detachment from sedimentary loading and slumping. The traps responsible for the fields in this volume are related either directly or indirectly to a fault block. The traps of Amposta, Cano Limon, Ninian, Renqiu, and Sarir are directly related to a fault block. Brent and Magnus fields are the result of traps formed by an unconformity truncation and a tilted fault block. Mobeetie field is the result of a trap indirectly related to a fault block. The anticline associated with the trap formed by differential compaction over a basement fault block. Red Oak field comprises traps both in a fault block and in an overlying anticline formed by differential compaction over the same fault block. With the exception of Cano Limon, all the fault blocks associated with these fields formed mainly under tensional stresses. The fault block associated with Cano Limon field formed by shearing in a strike-slip environment. Another aspect described in each field study is the history of its exploration and development.

  8. Single trap dynamics in electrolyte-gated Si-nanowire field effect transistors

    SciTech Connect (OSTI)

    Pud, S.; Li, J.; Offenhäusser, A.; Vitusevich, S. A., E-mail: s.vitusevich@fz-juelich.de [Peter Grünberg Institute (PGI-8), Forschungszentrum Jülich, 52425 Jülich (Germany); Gasparyan, F. [Peter Grünberg Institute (PGI-8), Forschungszentrum Jülich, 52425 Jülich (Germany); Department of Semiconductor Physics and Microelectronics, Yerevan State University, 1 Alex Manoogian St., 0025 Yerevan (Armenia); Petrychuk, M. [Radiophysics Faculty, T. Shevchenko National University of Kyiv, 60 Volodymyrska St., 01601 Kyiv (Ukraine)

    2014-06-21T23:59:59.000Z

    Liquid-gated silicon nanowire (NW) field effect transistors (FETs) are fabricated and their transport and dynamic properties are investigated experimentally and theoretically. Random telegraph signal (RTS) fluctuations were registered in the nanolength channel FETs and used for the experimental and theoretical analysis of transport properties. The drain current and the carrier interaction processes with a single trap are analyzed using a quantum-mechanical evaluation of carrier distribution in the channel and also a classical evaluation. Both approaches are applied to treat the experimental data and to define an appropriate solution for describing the drain current behavior influenced by single trap resulting in RTS fluctuations in the Si NW FETs. It is shown that quantization and tunneling effects explain the behavior of the electron capture time on the single trap. Based on the experimental data, parameters of the single trap were determined. The trap is located at a distance of about 2?nm from the interface Si/SiO{sub 2} and has a repulsive character. The theory of dynamic processes in liquid-gated Si NW FET put forward here is in good agreement with experimental observations of transport in the structures and highlights the importance of quantization in carrier distribution for analyzing dynamic processes in the nanostructures.

  9. Broadband laser cooling of trapped atoms with ultrafast pulses

    E-Print Network [OSTI]

    B. B. Blinov; R. N. Kohn Jr.; M. J. Madsen; P. Maunz; D. L. Moehring; C. Monroe

    2005-07-07T23:59:59.000Z

    We demonstrate broadband laser cooling of atomic ions in an rf trap using ultrafast pulses from a modelocked laser. The temperature of a single ion is measured by observing the size of a time-averaged image of the ion in the known harmonic trap potential. While the lowest observed temperature was only about 1 K, this method efficiently cools very hot atoms and can sufficiently localize trapped atoms to produce near diffraction-limited atomic images.

  10. Cold trapped positrons and progress to cold antihydrogen

    E-Print Network [OSTI]

    Estrada, John Karl, 1970-

    2002-01-01T23:59:59.000Z

    A new physical mechanism for positron accumulation is explained and demonstrated. Strongly magnetized Rydberg positronium is formed and then ionized, allowing us to trap equal numbers of either positrons or electrons over ...

  11. Antihydrogen Trapped in the ALPHA Experiment

    ScienceCinema (OSTI)

    None

    2011-04-25T23:59:59.000Z

    In 2010 the ALPHA collaboration succeeded in trapping antihydrogen atoms for the first time.[i]  Stored antihydrogen promises to be a unique tool for making high precision measurements of the structure of this first anti-atom. Achieving this milestone presented several substantial experimental challenges and this talk will describe how they were overcome.   The unique design features of the ALPHA apparatus will be explained.[ii]  These allow a high intensity positron source and an antiproton imaging detector similar to the one used in the ATHENA[iii] experiment to be combined with an innovative magnet design of the anti-atom trap. This seeks to minimise the perturbations to trapped charged particles which may cause particle loss and heating[iv].   The diagnostic techniques used to measure the diameter, number, density, and temperatures of both plasmas will be presented as will the methods developed to actively compress and cool of both plasma species to sizes and temperatures [v],[vi], [vii] where trapping attempts with a reasonable chance of success can be tried.   The results of the successful trapping experiments will be outlined as well as some subsequent experiments to improve the trapping rate and storage time. [i] 'Trapped antihydrogen' G.B. Andresen et al., Nature 468, 673 (2010) [ii]'A Magnetic Trap for Antihydrogen Confinement' W. Bertsche et al., Nucl. Instr. Meth. Phys. Res. A566, 746 (2006) [iii] Production and detection of cold antihydrogen atoms M.Amoretti et al., Nature 419, 456 (2002). [iv]' Antihydrogen formation dynamics in a multipolar neutral anti-atom trap' G.B. Andresen et al., Phys. Lett. B 685, 141 (2010) [v]' Evaporative Cooling of Antiprotons to Cryogenic Temperatures',                                   G.B. Andresen et al. Phys. Rev. Lett 105, 013003 (2010) [vi]'Compression of Antiproton Clouds for Antihydrogen Trapping' G. B. Andresen et al. Phys. Rev. Lett 100, 203401 (2008) [vii]  'Autoresonant Excitation of Antiproton Plasmas' G.B. Andresen et al., Phys. Rev. Lett. 106, 025002 (2011) Organizer: Ferdinand Hahn PH/DT Detector Seminar webpage  

  12. Thermoelectrically cooled water trap

    DOE Patents [OSTI]

    Micheels, Ronald H. (Concord, MA)

    2006-02-21T23:59:59.000Z

    A water trap system based on a thermoelectric cooling device is employed to remove a major fraction of the water from air samples, prior to analysis of these samples for chemical composition, by a variety of analytical techniques where water vapor interferes with the measurement process. These analytical techniques include infrared spectroscopy, mass spectrometry, ion mobility spectrometry and gas chromatography. The thermoelectric system for trapping water present in air samples can substantially improve detection sensitivity in these analytical techniques when it is necessary to measure trace analytes with concentrations in the ppm (parts per million) or ppb (parts per billion) partial pressure range. The thermoelectric trap design is compact and amenable to use in a portable gas monitoring instrumentation.

  13. Development of a Kingdon ion trap system for trapping externally injected highly charged ions

    SciTech Connect (OSTI)

    Numadate, Naoki; Okada, Kunihiro, E-mail: okada-k@sophia.ac.jp [Department of Physics, Sophia University, 7-1 Kioicho, Chiyoda, Tokyo 102-8554 (Japan); Nakamura, Nobuyuki [Institute for Laser Science, University of Electro-Communications, 1-5-1 Chofugaoka, Chofu, Tokyo 182-0021 (Japan); Tanuma, Hajime [Department of Physics, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397 (Japan)

    2014-10-15T23:59:59.000Z

    We have developed a Kingdon ion trap system for the purpose of the laboratory observation of the x-ray forbidden transitions of highly charged ions (HCIs). Externally injected Ar{sup q+} (q = 5?7) with kinetic energies of 6q keV were successfully trapped in the ion trap. The energy distribution of trapped ions is discussed in detail on the basis of numerical simulations. The combination of the Kingdon ion trap and the time-of-flight mass spectrometer enabled us to measure precise trapping lifetimes of HCIs. As a performance test of the instrument, we measured trapping lifetimes of Ar{sup q+} (q = 5?7) under a constant number density of H{sub 2} and determined the charge-transfer cross sections of Ar{sup q+}(q = 5, 6)-H{sub 2} collision systems at binary collision energies of a few eV. It was confirmed that the present cross section data are consistent with previous data and the values estimated by some scaling formula.

  14. Ion funnel ion trap and process

    DOE Patents [OSTI]

    Belov, Mikhail E [Richland, WA; Ibrahim, Yehia M [Richland, WA; Clowers, Biran H [West Richland, WA; Prior, David C [Hermiston, OR; Smith, Richard D [Richland, WA

    2011-02-15T23:59:59.000Z

    An ion funnel trap is described that includes a inlet portion, a trapping portion, and a outlet portion that couples, in normal operation, with an ion funnel. The ion trap operates efficiently at a pressure of .about.1 Torr and provides for: 1) removal of low mass-to-charge (m/z) ion species, 2) ion accumulation efficiency of up to 80%, 3) charge capacity of .about.10,000,000 elementary charges, 4) ion ejection time of 40 to 200 .mu.s, and 5) optimized variable ion accumulation times. Ion accumulation with low concentration peptide mixtures has shown an increase in analyte signal-to-noise ratios (SNR) of a factor of 30, and a greater than 10-fold improvement in SNR for multiply charged analytes.

  15. Fast optimal frictionless atom cooling in harmonic traps

    E-Print Network [OSTI]

    Xi Chen; A. Ruschhaupt; S. Schmidt; A. del Campo; D. Guery-Odelin; J. G. Muga

    2009-10-05T23:59:59.000Z

    A method is proposed to cool down atoms in a harmonic trap without phase-space compression as in a perfectly slow adiabatic expansion, i.e., keeping the populations of the instantaneous initial and final levels invariant, but in a much shorter time. This may require that the harmonic trap becomes an expulsive parabolic potential in some time interval. The cooling times achieved are also shorter than previous minimal times using optimal-control bang-bang methods and real frequencies.

  16. Asymmetric ion trap

    DOE Patents [OSTI]

    Barlow, S.E.; Alexander, M.L.; Follansbee, J.C.

    1997-12-02T23:59:59.000Z

    An ion trap having two end cap electrodes disposed asymmetrically about a center of a ring electrode is disclosed. The inner surface of the end cap electrodes are conformed to an asymmetric pair of equipotential lines of the harmonic formed by the application of voltages to the electrodes. The asymmetry of the end cap electrodes allows ejection of charged species through the closer of the two electrodes which in turn allows for simultaneously detecting anions and cations expelled from the ion trap through the use of two detectors charged with opposite polarity. 4 figs.

  17. Asymmetric ion trap

    DOE Patents [OSTI]

    Barlow, Stephan E. (Richland, WA); Alexander, Michael L. (Richland, WA); Follansbee, James C. (Pasco, WA)

    1997-01-01T23:59:59.000Z

    An ion trap having two end cap electrodes disposed asymmetrically about a center of a ring electrode. The inner surface of the end cap electrodes are conformed to an asymmetric pair of equipotential lines of the harmonic formed by the application of voltages to the electrodes. The asymmetry of the end cap electrodes allows ejection of charged species through the closer of the two electrodes which in turn allows for simultaneously detecting anions and cations expelled from the ion trap through the use of two detectors charged with opposite polarity.

  18. Optothermal Molecule Trap

    E-Print Network [OSTI]

    Duhr, S; Duhr, Stefan; Braun, Dieter

    2006-01-01T23:59:59.000Z

    Thermophoresis moves molecules along temperature gradients, typically from hot to cold. We superpose fluid flow with thermophoretic molecule flow under well defined microfluidic conditions, imaged by fluorescence microscopy. DNA is trapped and accumulated 16-fold in regions where both flows move in opposite directions. Strong 800-fold accumulation is expected, however with slow trapping kinetics. The experiment is equally described by a three-dimensional and one-dimensional analytical model. As an application, we show how a radially converging temperature field confines short DNA into a 10 um small spot.

  19. CONTINUOUS FLOW "RAIL-AND-TRAP" MICROFLUIDIC PROCESSORS FOR AUTONOMOUS

    E-Print Network [OSTI]

    Lin, Liwei

    CONTINUOUS FLOW "RAIL-AND-TRAP" MICROFLUIDIC PROCESSORS FOR AUTONOMOUS BEAD-BASED MIXING laborious and time intensive fluidic mixing procedures. Although microfluidic platforms offer significant, here we present a microfluidic "rail-and-trap" processor that functions autonomously under continuous

  20. February 1, 1994 / Vol. 19, No. 3 / OPTICS LETTERS Spin relaxation of optically trapped atoms by light scattering

    E-Print Network [OSTI]

    Heinzen, Daniel J.

    February 1, 1994 / Vol. 19, No. 3 / OPTICS LETTERS Spin relaxation of optically trapped atoms of optically trapped atoms that is due to light scattering from the trap laser. We observe relaxation times greater than 2 s for ground-state hyperfine-levelpopulations of 85 Rb atoms trapped in an optical dipole

  1. Steam trap monitor

    DOE Patents [OSTI]

    Ryan, Michael J. (Plainfield, IL)

    1988-01-01T23:59:59.000Z

    A steam trap monitor positioned downstream of a steam trap in a closed steam system includes a first sensor (the combination of a hot finger and thermocouple well) for measuring the energy of condensate and a second sensor (a cold finger) for measuring the total energy of condensate and steam in the line. The hot finger includes one or more thermocouples for detecting condensate level and energy, while the cold finger contains a liquid with a lower boiling temperature than that of water. Vapor pressure from the liquid is used to do work such as displacing a piston or bellows in providing an indication of total energy (steam+condensate) of the system. Processing means coupled to and responsive to outputs from the thermocouple well hot and cold fingers subtracts the condensate energy as measured by the hot finger and thermocouple well from the total energy as measured by the cold finger to provide an indication of the presence of steam downstream from the trap indicating that the steam trap is malfunctioning.

  2. Bose-Einstein Condensation in an electro-pneumatically transformed quadrupole-Ioffe magnetic trap

    E-Print Network [OSTI]

    Sunil Kumar; Sumit Sarkar; Gunjan Verma; Chetan Vishwakarma; Md. Noaman; Umakant Rapol

    2014-08-20T23:59:59.000Z

    We report a novel approach for preparing a Bose-Einstein condensate (BEC) of $^{87}$Rb atoms using electro-pneumatically driven transfer of atoms into a Quadrupole-Ioffe magnetic trap (QUIC Trap). More than 5$\\times$$10^{8}$ atoms from a Magneto-optical trap are loaded into a spherical quadrupole trap and then these atoms are transferred into an Ioffe trap by moving the Ioffe coil towards the center of the quadrupole coil, thereby, changing the distance between quadrupole trap center and the Ioffe coil. The transfer efficiency is more than 80 \\%. This approach is different from a conventional approach of loading the atoms into a QUIC trap wherein the spherical quadrupole trap is transformed into a QUIC trap by changing the currents in the quadrupole and the Ioffe coils. The phase space density is then increased by forced rf evaporative cooling to achieve the Bose-Einstein condensation having more than $10^{5}$ atoms.

  3. Master equation approach to protein folding and kinetic traps

    E-Print Network [OSTI]

    Marek Cieplak; Malte Henkel; Jan Karbowski; Jayanth R. Banavar

    1998-04-21T23:59:59.000Z

    The master equation for 12-monomer lattice heteropolymers is solved numerically and the time evolution of the occupancy of the native state is determined. At low temperatures, the median folding time follows the Arrhenius law and is governed by the longest relaxation time. For good folders, significant kinetic traps appear in the folding funnel whereas for bad folders, the traps also occur in non-native energy valleys.

  4. Final Technical Report of project: "Contactless Real-Time Monitoring of Paper Mechanical Behavior During Papermaking"

    SciTech Connect (OSTI)

    Emmanuel Lafond; Paul Ridgway; Ted Jackson; Rick Russo; Ken Telschow; Vance Deason; Yves Berthelot; David Griggs; Xinya Zhang; Gary Baum

    2005-08-30T23:59:59.000Z

    The early precursors of laser ultrasonics on paper were Prof. Y. Berthelot from the Georgia Institute of Technology/Mechanical Engineering department, and Prof. P. Brodeur from the Institute of Paper Science and Technology, both located in Atlanta, Georgia. The first Ph.D. thesis that shed quite some light on the topic, but also left some questions unanswered, was completed by Mont A. Johnson in 1996. Mont Johnson was Prof. Berthelot's student at Georgia Tech. In 1997 P. Brodeur proposed a project involving himself, Y. Berthelot, Dr. Ken Telschow and Mr. Vance Deason from INL, Honeywell-Measurex and Dr. Rick Russo from LBNL. The first time the proposal was not accepted and P. Brodeur decided to re-propose it without the involvement from LBNL. Rick Russo proposed a separate project on the same topic on his side. Both proposals were finally accepted and work started in the fall of 1997 on the two projects. Early on, the biggest challenge was to find an optical detection method which could detect laser-induced displacements of the web surface that are of the order of .1 micron in the ultrasonic range. This was to be done while the web was having an out-of-plane amplitude of motion in the mm range due to web flutter; while moving at 10 m/s to 30 m/s in the plane of the web, on the paper machine. Both teams grappled with the same problems and tried similar methods in some cases, but came up with two similar but different solutions one year later. The IPST, GT, INL team found that an interferometer made by Lasson Technologies Inc. using the photo-induced electro-motive force in Gallium Arsenide was able to detect ultrasonic waves up to 12-15 m/s. It also developed in house an interferometer using the Two-Wave Mixing effect in photorefractive crystals that showed good promises for on-line applications, and experimented with a scanning mirror to reduce motion-induced texture noise from the web and improve signal to noise ratio. On its side, LBNL had the idea to combine a commercial Mach-Zehnder interferometer to a spinning mirror synchronized to the web speed, in order to make almost stationary measurements. The method was demonstrated at up to 10 m/s. Both teams developed their own version of a web simulator that was driving a web of paper at 10 m/s or higher. The Department of Energy and members of the Agenda 2020 started to make a push for merging the two projects. This made sense because their topics were really identical but this was not well received by Prof. Brodeur. Finally IPST decided to reassign the direction of the IPST-INL-GT project in the spring of 1999 to Prof. Chuck Habeger so that the two teams could work together. Also at this time, Honeywell-Measurex dropped as a member of the team. It was replaced by ABB Industrial Systems whose engineers had extensive previous experience of working with ultrasonic sensors on paperboard. INL also finished its work on the project as its competencies were partly redundant with LBNL. From the summer of 1999, the IPST-GT and LBNL teams were working together and helped each other often by collaborating and visiting either laboratory when was necessary. Around the beginning of 2000, began an effort at IPST to create an off-line laser-ultrasonics instrument that could perform automated measurements of paper and paperboard's bending stiffness. It was widely known that the mechanical bending tests of paper used for years by the paper industry were very inaccurate and exhibited poor reproducibility; therefore the team needed a new instrument of reference to validate its future on-line results. In 1999-2000, the focus of the on-line instrument was on a pre-industrial demonstration on a pilot coater while reducing the damage to the web caused by the generation laser, below the threshold where it could be visible by the naked eye. During the spring of 2000 Paul Ridgway traveled to IPST and brought with him a redesigned system still using the same Mach-Zehnder interferometer as before, but this time employing an electric motor-driven spinning mirror instead of the previously belt-driven m

  5. Wednesday, January 30, 2013 Infrared Trapping the "Greenhouse Effect"

    E-Print Network [OSTI]

    Toohey, Darin W.

    Wednesday, January 30, 2013 Infrared Trapping ­ the "Greenhouse Effect" Goals ­ to look is the same as a 1.8 degree F change. #12;Last time - Greenhouse effect demo Selective absorption. Greenhouse

  6. Time Stamp Attack in Smart Grid: Physical Mechanism and Damage Analysis

    E-Print Network [OSTI]

    Gong, Shuping; Li, Husheng; Dimitrovski, Aleksandar D

    2012-01-01T23:59:59.000Z

    Many operations in power grids, such as fault detection and event location estimation, depend on precise timing information. In this paper, a novel time stamp attack (TSA) is proposed to attack the timing information in smart grid. Since many applications in smart grid utilize synchronous measurements and most of the measurement devices are equipped with global positioning system (GPS) for precise timing, it is highly probable to attack the measurement system by spoofing the GPS. The effectiveness of TSA is demonstrated for three applications of phasor measurement unit (PMU) in smart grid, namely transmission line fault detection, voltage stability monitoring and event locationing.

  7. Nanoantennas for enhanced light trapping in transparent organic solar cells

    E-Print Network [OSTI]

    Voroshilov, Pavel M; Belov, Pavel A

    2014-01-01T23:59:59.000Z

    We propose a light-trapping structure offering a significant enhancement of photovoltaic absorption in transparent organic solar cells operating at infrared while the visible light transmission keeps sufficiently high. The main mechanism of light trapping is related with the excitation of collective oscillations of the metal nanoantenna arrays, characterized by advantageous field distribution in the volume of the solar cell. It allows more than triple increase of infrared photovoltaic absorption.

  8. Simplified motional heating rate measurements of trapped ions

    E-Print Network [OSTI]

    Epstein, R J; Leibfried, D; Wesenberg, J H; Bollinger, J J; Amini, J M; Blakestad, R B; Britton, J; Home, J P; Itano, W M; Jost, J D; Knill, E; Langer, C; Ozeri, R; Shiga, N; Wineland, D J

    2007-01-01T23:59:59.000Z

    We have measured motional heating rates of trapped atomic ions, a factor that can influence multi-ion quantum logic gate fidelities. Two simplified techniques were developed for this purpose: one relies on Raman sideband detection implemented with a single laser source, while the second is even simpler and is based on time-resolved fluorescence detection during Doppler recooling. We applied these methods to determine heating rates in a microfrabricated surface-electrode trap made of gold on fused quartz, which traps ions 40 microns above its surface. Heating rates obtained from the two techniques were found to be in reasonable agreement. In addition, the trap gives rise to a heating rate of 300 plus or minus 30 per second for a motional frequency of 5.25 MHz, substantially below the trend observed in other traps.

  9. Short time scale thermal mechanical shock wave propagation in high performance microelectronic packaging configuration

    E-Print Network [OSTI]

    Nagaraj, Mahavir

    2004-11-15T23:59:59.000Z

    for various combinations of t1 and t2 and the parabolic case..................................... 34 4-2 Time domain plots of normalized displacement at 10 nm for various combinations of t1 and t2 and the parabolic case .................. 35 4...-3 Time domain plots of normalized temperature at 30 nm for various combinations of t1 and t2 and the parabolic case .................. 37 4-4 Time domain plots of normalized displacement at 30 nm for various combinations of t1 and t2...

  10. Time and location differentiated NOX control in competitive electricity markets using cap-and-trade mechanisms

    E-Print Network [OSTI]

    Martin, Katherine C.

    2007-01-01T23:59:59.000Z

    Due to variations in weather and atmospheric chemistry, the timing and location of nitrogen oxide (NOX) reductions determine their effectiveness in reducing ground-level ozone, which adversely impacts human health. Electric ...

  11. Evaluating Policies and Mechanisms for Supporting Embedded, Real-Time Applications with CORBA 3.0

    E-Print Network [OSTI]

    , and weight/power consumption, software techniques used to develop real-time systems have historically lagged,schmidtg@uci.edu Irfan Pyarali, and David L. Levine Electrical & Computer Engineering Dept. ffredk

  12. Steam Trap Application

    E-Print Network [OSTI]

    Murphy, J. J.

    1982-01-01T23:59:59.000Z

    ~ ~ [EMPERATURE ~ -Surface pyrometer may indicate fluctuation due to expected in termittent discharge. -Blow down strainer, -Look for other leaks 5 ~e~7;~~rP~;i;~h~d~~:cer ~ l/month most process ~ l/week critical process ~ and air heaters in winter... valves must be -Small leaks undetected condensate & steam arf being trap line size -Electrical safety-some discharged simultaneorsly -Added cost of test tee,valves devices -Some devices need cal~bration en nipples, etc_ -Infra red devices nee~ cali- Z...

  13. Schwinger Mechanism for Gluon Pair Production in the Presence of Arbitrary Time Dependent Chromo-Electric Field in Arbitrary Gauge

    E-Print Network [OSTI]

    Gouranga C Nayak

    2009-10-02T23:59:59.000Z

    We study non-perturbative gluon pair production from arbitrary time dependent chromo-electric field E^a(t) with arbitrary color index a =1,2,...8 via Schwinger mechanism in arbitrary covariant background gauge \\alpha. We show that the probability of non-perturbative gluon pair production per unit time per unit volume per unit transverse momentum \\frac{dW}{d^4xd^2p_T} is independent of gauge fixing parameter \\alpha. Hence the result obtained in the Fynman-'t Hooft gauge, \\alpha=1, is the correct gauge invariant and gauge parameter \\alpha independent result.

  14. The Elimination of Steam Traps

    E-Print Network [OSTI]

    Dickman, F.

    claims and misinformation gener ated by over thirty-six steam trap manufacturers in the United States alone. A PARTIAL LIST OF STEAM TRAP MANUFACTURERS AAF GESTRA ANDERSON HIROSS ARMSTRONG HOFFMAN BARNES &JONES HONEYWELL BRAUKMANN BESTOBELL... removal had been devised and these same methods, with minor variations, are employed today. The inverted bucket trap was in vented in 1910 by Otto Arner, a friend of Adam Armstrong. Armstrong began his business career by making bicycle spokes...

  15. Trapping triply ionized thorium isotopes.

    E-Print Network [OSTI]

    Churchill, Layne Russell

    2010-01-01T23:59:59.000Z

    ??Cold trapped ions have many applications in quantum information science and precision metrology. In this thesis, we present progress toward two objectives involving ions confined… (more)

  16. Mechanisms of Peptide Fragmentation from Time-and Energy-Resolved

    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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces andMapping the NanoscaleMechanical Behavior ofAPS ... Search

  17. Exciton self-trapping in bulk polyethylene

    E-Print Network [OSTI]

    D. Ceresoli; M. C. Righi; E. Tosatti; S. Scandolo; G. Santoro; S. Serra

    2005-07-13T23:59:59.000Z

    We studied theoretically the behavior of an injected electron-hole pair in crystalline polyethylene. Time-dependent adiabatic evolution by ab-initio molecular dynamics simulations show that the pair will become self-trapped in the perfect crystal, with a trapping energy of about 0.38 eV, with formation of a pair of trans-gauche conformational defects, three C$_2$H$_4$ units apart on the same chain. The electron is confined in the inter-chain pocket created by a local, 120$^\\circ$ rotation of the chain between the two defects, while the hole resides on the chain and is much less bound. Despite the large energy stored in the trapped excitation, there does not appear to be a direct non-radiative channel for electron-hole recombination. This suggests that intrinsic self-trapping of electron-hole pairs inside the ideal quasi-crystalline fraction of PE might not be directly relevant for electrical damage in high-voltage cables.

  18. Mechanisms for mechanical trapping of geologically sequestered carbon dioxide

    E-Print Network [OSTI]

    Cohen, Yossi

    Carbon dioxide (CO[subscript 2]) sequestration in subsurface reservoirs is important for limiting atmospheric CO[subscript 2] concentrations. However, a complete physical picture able to predict the structure developing ...

  19. Physiologically realistic modelling of a mechanism for neural representation of intervals of time

    E-Print Network [OSTI]

    Fukai, Tomoki

    -8610, Japan c CREST, Japan Science and Technology (JST), Saitama 332-0012, Japan Abstract A model, Fuji Xerox Co. Ltd., 430 Sakai, Nakai-machi, Ashigarakami-gun, Kanagawa 259-0157, Japan b Department as well as the difference stated above, will lead us to the idea that an interval of time, T

  20. Meteoritical and dynamical constraints on the growth mechanisms and formation times of asteroids and Jupiter

    E-Print Network [OSTI]

    Edward R. D. Scott

    2006-07-13T23:59:59.000Z

    Peak temperatures inside meteorite parent bodies are closely linked to accretion times. Most iron meteorites come from bodies that accreted 3-5 Myr after CAIs formed. This precludes formation of Jupiter via a gravitational instability <1 Myr after the solar nebula formed, and strongly favors core accretion. Shocks formed by gravitational instabilities in the disk, proto-Jupiter, or by planetary embryos may have produced some chondrules. The minimum lifetime for the solar nebula of 3-5 Myr inferred from CAI and chondrule ages may exceed the median 3 Myr lifetime for protoplanetary disks, but is well within the total 1-10 Myr range. Shorter formation times for extrasolar planets may help to explain why their orbits are unlike those of solar giant planets.

  1. Cryogenic silicon surface ion trap

    E-Print Network [OSTI]

    Michael Niedermayr; Kirill Lakhmanskiy; Muir Kumph; Stefan Partel; Johannes Edlinger; Michael Brownnutt; Rainer Blatt

    2014-03-20T23:59:59.000Z

    Trapped ions are pre-eminent candidates for building quantum information processors and quantum simulators. They have been used to demonstrate quantum gates and algorithms, quantum error correction, and basic quantum simulations. However, to realise the full potential of such systems and make scalable trapped-ion quantum computing a reality, there exist a number of practical problems which must be solved. These include tackling the observed high ion-heating rates and creating scalable trap structures which can be simply and reliably produced. Here, we report on cryogenically operated silicon ion traps which can be rapidly and easily fabricated using standard semiconductor technologies. Single $^{40}$Ca$^+$ ions have been trapped and used to characterize the trap operation. Long ion lifetimes were observed with the traps exhibiting heating rates as low as $\\dot{\\bar{n}}=$ 0.33 phonons/s at an ion-electrode distance of 230 $\\mu$m. These results open many new avenues to arrays of micro-fabricated ion traps.

  2. Optimal traps in graphene

    E-Print Network [OSTI]

    C. A. Downing; A. R. Pearce; R. J. Churchill; M. E. Portnoi

    2015-03-27T23:59:59.000Z

    We transform the two-dimensional Dirac-Weyl equation, which governs the charge carriers in graphene, into a non-linear first-order differential equation for scattering phase shift, using the so-called variable phase method. This allows us to utilize the Levinson Theorem to find zero-energy bound states created electrostatically in realistic structures. These confined states are formed at critical potential strengths, which leads to us posit the use of `optimal traps' to combat the chiral tunneling found in graphene, which could be explored experimentally with an artificial network of point charges held above the graphene layer. We also discuss scattering on these states and find the zero angular momentum states create a dominant peak in scattering cross-section as energy tends towards the Dirac point energy, suggesting a dominant contribution to resistivity.

  3. Precursory signatures of protein folding/unfolding: From time series correlation analysis to atomistic mechanisms

    SciTech Connect (OSTI)

    Hsu, P. J.; Lai, S. K., E-mail: sklai@coll.phy.ncu.edu.tw [Complex Liquids Laboratory, Department of Physics, National Central University, Chungli 320 Taiwan (China); Molecular Science and Technology Program, Taiwan International Graduate Program, Academia Sinica, Taipei 115, Taiwan (China); Cheong, S. A. [Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371 (Singapore)

    2014-05-28T23:59:59.000Z

    Folded conformations of proteins in thermodynamically stable states have long lifetimes. Before it folds into a stable conformation, or after unfolding from a stable conformation, the protein will generally stray from one random conformation to another leading thus to rapid fluctuations. Brief structural changes therefore occur before folding and unfolding events. These short-lived movements are easily overlooked in studies of folding/unfolding for they represent momentary excursions of the protein to explore conformations in the neighborhood of the stable conformation. The present study looks for precursory signatures of protein folding/unfolding within these rapid fluctuations through a combination of three techniques: (1) ultrafast shape recognition, (2) time series segmentation, and (3) time series correlation analysis. The first procedure measures the differences between statistical distance distributions of atoms in different conformations by calculating shape similarity indices from molecular dynamics simulation trajectories. The second procedure is used to discover the times at which the protein makes transitions from one conformation to another. Finally, we employ the third technique to exploit spatial fingerprints of the stable conformations; this procedure is to map out the sequences of changes preceding the actual folding and unfolding events, since strongly correlated atoms in different conformations are different due to bond and steric constraints. The aforementioned high-frequency fluctuations are therefore characterized by distinct correlational and structural changes that are associated with rate-limiting precursors that translate into brief segments. Guided by these technical procedures, we choose a model system, a fragment of the protein transthyretin, for identifying in this system not only the precursory signatures of transitions associated with ? helix and ? hairpin, but also the important role played by weaker correlations in such protein folding dynamics.

  4. Theory and application of planar ion traps

    E-Print Network [OSTI]

    Pearson, Christopher Elliott

    2006-01-01T23:59:59.000Z

    In this thesis, we investigate a new geometry of Paul trap with electrodes in a plane. These planar ion traps are compatible with modern silicon microfabrication, and can be scaled up to large arrays with multiple trapping ...

  5. Schwinger Mechanism for Quark-Antiquark Production in the Presence of Arbitrary Time Dependent Chromo-Electric Field

    E-Print Network [OSTI]

    Gouranga C. Nayak

    2011-05-23T23:59:59.000Z

    We study the Schwinger mechanism in QCD in the presence of an arbitrary time-dependent chromo-electric background field $E^a(t)$ with arbitrary color index $a$=1,2,...8 in SU(3). We obtain an exact result for the non-perturbative quark (antiquark) production from an arbitrary $E^a(t)$ by directly evaluating the path integral. We find that the exact result is independent of all the time derivatives $\\frac{d^nE^a(t)}{dt^n}$ where $n=1,2,...\\infty$. This result has the same functional dependence on two Casimir invariants $[E^a(t)E^a(t)]$ and $[d_{abc}E^a(t)E^b(t)E^c(t)]^2$ as the constant chromo-electric field $E^a$ result with the replacement: $E^a \\rightarrow E^a(t)$. This result relies crucially on the validity of the shift conjecture, which has not yet been established.

  6. Neutron lifetime measurements using gravitationally trapped ultracold neutrons

    SciTech Connect (OSTI)

    Serebrov, A. P.; Varlamov, V. E.; Kharitonov, A. G.; Fomin, A. K.; Krasnoschekova, I. A.; Lasakov, M. S.; Taldaev, R. R.; Vassiljev, A. V.; Zherebtsov, O. M. [Petersburg Nuclear Physics Institute, Russian Academy of Sciences, RU-188300 Gatchina, Leningrad District (Russian Federation); Pokotilovski, Yu. N. [Joint Institute for Nuclear Research, RU-141980 Dubna, Moscow Region (Russian Federation); Geltenbort, P. [Institut Max von Laue Paul Langevin, Boite Postal 156, F-38042 Grenoble Cedex 9 (France)

    2008-09-15T23:59:59.000Z

    Our experiment using gravitationally trapped ultracold neutrons (UCN) to measure the neutron lifetime is reviewed. Ultracold neutrons were trapped in a material bottle covered with perfluoropolyether. The neutron lifetime was deduced from comparison of UCN losses in the traps with different surface-to-volume ratios. The precise value of the neutron lifetime is of fundamental importance to particle physics and cosmology. In this experiment, the UCN storage time is brought closer to the neutron lifetime than in any experiments before: the probability of UCN losses from the trap was only 1% of that for neutron {beta} decay. The neutron lifetime obtained, 878.5{+-}0.7{sub stat}{+-}0.3{sub sys} s, is the most accurate experimental measurement to date.

  7. Neutron lifetime measurements using gravitationally trapped ultracold neutrons

    E-Print Network [OSTI]

    A. P. Serebrov; V. E. Varlamov; A. G. Kharitonov; A. K. Fomin; Yu. N. Pokotilovski; P. Geltenbort; I. A. Krasnoschekova; M. S. Lasakov; R. R. Taldaev; A. V. Vassiljev; O. M. Zherebtsov

    2007-02-06T23:59:59.000Z

    Our experiment using gravitationally trapped ultracold neutrons (UCN) to measure the neutron lifetime is reviewed. Ultracold neutrons were trapped in a material bottle covered with perfluoropolyether. The neutron lifetime was deduced from comparison of UCN losses in the traps with different surface-to-volume ratios. The precise value of the neutron lifetime is of fundamental importance to particle physics and cosmology. In this experiment, the UCN storage time is brought closer to the neutron lifetime than in any experiments before:the probability of UCN losses from the trap was only 1% of that for neutron beta decay. The neutron lifetime obtained,878.5+/-0.7stat+/-0.3sys s, is the most accurate experimental measurement to date.

  8. Rainbow trapping of guided waves

    E-Print Network [OSTI]

    Polanco, Javier; Fitzgerald, Rosa M; Leskova, Tamara A; Maradudin, Alexei A

    2011-01-01T23:59:59.000Z

    Rainbow trapping of guided waves Javier Polanco and Rosa M.the propagation of a wave packet that is a superpositionof three s-polarized guided waves with different frequencies

  9. Inspect and Repair Steam Traps

    SciTech Connect (OSTI)

    Not Available

    2006-01-01T23:59:59.000Z

    This revised ITP tip sheet on inspecting and repairing steam traps provide how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

  10. Sticky Traps for Large Scale House Fly (Diptera: Muscidae) Trapping in New York Poultry Facilities1

    E-Print Network [OSTI]

    Kaufman, Phillip E.

    Sticky Traps for Large Scale House Fly (Diptera: Muscidae) Trapping in New York Poultry Facilities1 traps were evaluated under field conditions in two commercial high-rise, caged-layer poultry facilities-layerpoultry facilities. One side of each poultry facil- ity received traps with 1.2 m of exposed adhesive,whereas traps

  11. Measuring the Neutron Lifetime Using Magnetically Trapped Neutrons

    E-Print Network [OSTI]

    C. M. O'Shaughnessy; R. Golub; K. W. Schelhammer; C. M. Swank; P. -N. Seo; P. R. Huffman; S. N. Dzhosyuk; C. E. H. Mattoni; L. Yang; J. M. Doyle; K. J. Coakley; A. K. Thompson; H. P. Mumm; S. K. Lamoreaux; G. Yang

    2009-03-31T23:59:59.000Z

    The neutron beta-decay lifetime plays an important role both in understanding weak interactions within the framework of the Standard Model and in theoretical predictions of the primordial abundance of 4He in Big Bang Nucleosynthesis. In previous work, we successfully demonstrated the trapping of ultracold neutrons (UCN) in a conservative potential magnetic trap. A major upgrade of the apparatus is nearing completion at the National Institute of Standards and Technology Center for Neutron Research (NCNR). In our approach, a beam of 0.89 nm neutrons is incident on a superfluid 4He target within the minimum field region of an Ioffe-type magnetic trap. A fraction of the neutrons is downscattered in the helium to energies <200 neV, and those in the appropriate spin state become trapped. The inverse process is suppressed by the low phonon density of helium at temperatures less than 200 mK, allowing the neutron to travel undisturbed. When the neutron decays the energetic electron ionizes the helium, producing scintillation light that is detected using photomultiplier tubes. Statistical limitations of the previous apparatus will be alleviated by significant increases in field strength and trap volume resulting in twenty times more trapped neutrons.

  12. Temporally, spatially, and spectrally resolved barrier discharge produced in trapped helium gas at atmospheric pressure

    SciTech Connect (OSTI)

    Chiper, Alina Silvia; Popa, Gheorghe [Faculty of Physics, Alexandru Ioan Cuza University, 700506 Iasi (Romania)] [Faculty of Physics, Alexandru Ioan Cuza University, 700506 Iasi (Romania)

    2013-06-07T23:59:59.000Z

    Experimental study was made on induced effects by trapped helium gas in the pulsed positive dielectric barrier discharge (DBD) operating in symmetrical electrode configuration at atmospheric pressure. Using fast photography technique and electrical measurements, the differences in the discharge regimes between the stationary and the flowing helium are investigated. It was shown experimentally that the trapped gas atmosphere (TGA) has notable impact on the barrier discharge regime compared with the influence of the flowing gas atmosphere. According to our experimental results, the DBD discharge produced in trapped helium gas can be categorized as a multi-glow (pseudo-glow) discharge, each discharge working in the sub-normal glow regime. This conclusion is made by considering the duration of current pulse (few {mu}s), their maximum values (tens of mA), the presence of negative slope on the voltage-current characteristic, and the spatio-temporal evolution of the most representative excited species in the discharge gap. The paper focuses on the space-time distribution of the active species with a view to better understand the pseudo-glow discharge mechanism. The physical basis for these effects was suggested. A transition to filamentary discharge is suppressed in TGA mode due to the formation of supplementary source of seed electrons by surface processes (by desorption of electrons due to vibrationally excited nitrogen molecules, originated from barriers surfaces) rather than volume processes (by enhanced Penning ionisation). Finally, we show that the pseudo-glow discharge can be generated by working gas trapping only; maintaining unchanged all the electrical and constructive parameters.

  13. Integrated photonic structures for light trapping in thin-film Si solar cells

    E-Print Network [OSTI]

    Sheng, Xing

    We explore the mechanisms for an efficient light trapping structure for thin-film silicon solar cells. The design combines a distributed Bragg reflector (DBR) and periodic gratings. Using photonic band theories and numerical ...

  14. Cs-Exchange in Birnessite: Raction Mechanisms Inferred from Time-Resolved X-ray Diffraction and Transmission Electron Microscopy

    SciTech Connect (OSTI)

    Lopano, C.; Heaney, P; Post, J

    2009-01-01T23:59:59.000Z

    We have explored the exchange of Cs for interlayer Na in birnessite using several techniques, including transmission electron microscopy (TEM) and time-resolved synchrotron X-ray diffraction (XRD). Our goal was to test which of two possible exchange mechanisms is operative during the reaction: (1) diffusion of cations in and out of the interlayer or (2) dissolution of Na-birnessite and reprecipitation of Cs-birnessite. The appearance of distinct XRD peaks for Na- and Cs-rich phases in partially exchanged samples offered support for a simple diffusion model, but it was inconsistent with the compositional and crystallographic homogeneity of (Na,Cs)-birnessite platelets from core to rim as ascertained by TEM. Time-resolved XRD revealed systematic changes in the structure of the emergent Cs-rich birnessite phase during exchange, in conflict with a dissolution and reprecipitation model. Instead, we propose that exchange occurred by sequential delamination of Mn oxide octahedral sheets. Exfoliation of a given interlayer region allowed for wholesale replacement of Na by Cs and was rapidly followed by reassembly. This model accounts for the rapidity of metal exchange in birnessite, the co-existence of distinct Na- and Cs-birnessite phases during the process of exchange, and the uniformly mixed Na- and Cs-compositions ascertained from point analyses by selected area electron diffraction and energy dispersive spectroscopy of partially exchanged grains.

  15. Fidelity decay in trapped Bose-Einstein condensates

    E-Print Network [OSTI]

    G. Manfredi; P. -A. Hervieux

    2008-01-29T23:59:59.000Z

    The quantum coherence of a Bose-Einstein condensate is studied using the concept of quantum fidelity (Loschmidt echo). The condensate is confined in an elongated anharmonic trap and subjected to a small random potential such as that created by a laser speckle. Numerical experiments show that the quantum fidelity stays constant until a critical time, after which it drops abruptly over a single trap oscillation period. The critical time depends logarithmically on the number of condensed atoms and on the perturbation amplitude. This behavior may be observable by measuring the interference fringes of two condensates evolving in slightly different potentials.

  16. Optical Trapping by Radiometric Flow

    E-Print Network [OSTI]

    William L. Clarke

    1998-12-13T23:59:59.000Z

    Micron sized, neutral, non-dielectric particles immersed in a viscous fluid can be trapped in the focal plane of a Gaussian beam. A particle can absorb energy from such a beam with a large radial intensity gradient, resulting in substantial temperature gradients and a radiometric torque which causes it to spin rapidly about an axis perpendicular to the flux of radiant energy. The particles are also observed to orbit around the optical axis. Here we investigate the fundamental physics of this system, the Radiometric Particle Trap, and discuss its force laws using gas-kinetic theory.

  17. Hybrid particle traps and conditioning procedure for gas insulated transmission lines

    DOE Patents [OSTI]

    Dale, Steinar J. (Monroeville, PA); Cookson, Alan H. (Churchill, PA)

    1982-01-01T23:59:59.000Z

    A gas insulated transmission line includes an outer sheath, an inner condor within the outer sheath, insulating supports supporting the inner conductor within the outer sheath, and an insulating gas electrically insulating the inner conductor from the outer sheath. An apertured particle trapping ring is disposed within the outer sheath, and the trapping ring has a pair of dielectric members secured at each longitudinal end thereof, with the dielectric members extending outwardly from the trapping ring along an arc. A support sheet having an adhesive coating thereon is secured to the trapping ring and disposed on the outer sheath within the low field region formed between the trapping ring and the outer sheath. A conditioning method used to condition the transmission line prior to activation in service comprises applying an AC voltage to the inner conductor in a plurality of voltage-time steps, with the voltage-time steps increasing in voltage magnitude while decreasing in time duration.

  18. Equilibrium Theory for a Particle Pulled by a Moving Optical Trap

    E-Print Network [OSTI]

    R. Dean Astumian

    2006-08-16T23:59:59.000Z

    The viscous drag on a colloidal particle pulled through solution by an optical trap is large enough that on experimentally relavant time scales the mechanical force exerted by the trap is equal and op- posite the viscous drag force. The rapid mechanical equilibritation allows the system to be modeled using equilibrium theory, where the effects of the energy dissipation (thermodynamic disequilibrium) show up only in the coordinate transformations that map the system from the laboratory frame of reference, relative to which the particle is moving, to a frame of reference in which the particle is, on average, stationary and on which the stochastic dynamics is governed by a canonical equilib- rium distribution function. The simple equations in the stationary frame can be analyzed using the Onsager-Machlup theory for stochastic systems and provide generalizations of equilibrium and near equilibrium concepts such as detailed balance and fluctuation-dissipation relations applicable to a wide range of systems including molecular motors, pumps, and other nano-scale machines.

  19. Charge Trapping in Carbon Nanotube Loops Demonstrated by Electrostatic

    E-Print Network [OSTI]

    Nygård, Jesper

    Charge Trapping in Carbon Nanotube Loops Demonstrated by Electrostatic Force Microscopy Thomas Sand ABSTRACT Electronic devices made from carbon nanotubes (CNTs) can be greatly affected by substrate charges nanotube loops for extended periods of time, showing that nanotubes can act as confining barriers

  20. Electron Trapping in Shear Alfven Waves that Power the Aurora

    SciTech Connect (OSTI)

    Watt, Clare E. J.; Rankin, Robert [University of Alberta, Edmonton, Alberta (Canada)

    2009-01-30T23:59:59.000Z

    Results from 1D Vlasov drift-kinetic plasma simulations reveal how and where auroral electrons are accelerated along Earth's geomagnetic field. In the warm plasma sheet, electrons become trapped in shear Alfven waves, preventing immediate wave damping. As waves move to regions with larger v{sub Te}/v{sub A}, their parallel electric field decreases, and the trapped electrons escape their influence. The resulting electron distribution functions compare favorably with in situ observations, demonstrating for the first time a self-consistent link between Alfven waves and electrons that form aurora.

  1. Optical trapping for undergraduates D. C. Appleyard

    E-Print Network [OSTI]

    Lang, Matthew

    Optical trapping for undergraduates D. C. Appleyard Department of Biological Engineering September 2006 The detailed design of a robust and inexpensive optical trap system is presented. The system experimental modules are described to cover basic concepts in optical trapping and biophysics at a level

  2. Finite element simulations of hydrodynamic trapping in microfluidic particle-trap array systems

    E-Print Network [OSTI]

    Nehorai, Arye

    Finite element simulations of hydrodynamic trapping in microfluidic particle- trap array systems;Finite element simulations of hydrodynamic trapping in microfluidic particle-trap array systems Xiaoxiao) simulation is a powerful tool in the design and implementation of microfluidic systems, especially

  3. Noise and microresonance of critical current in Josephson junction induced by Kondo trap states

    E-Print Network [OSTI]

    Ansari, Mohammad H

    2011-01-01T23:59:59.000Z

    We analyze the impact of trap states in the oxide layer of a superconducting tunnel junctions, on the fluctuation of the Josephson critical current, thus on coherence in superconducting qubits. Two mechanisms are usually considered: the current blockage due to repulsion at the occupied trap states, and the noise from electrons hopping across a trap. We extend previous studies of noninteracting traps to the case where the traps have on-site electron repulsion inside one ballistic channel. The repulsion not only allows the appropriate temperature dependence of 1/f noise, but also is a control to the coupling between the computational qubit and the spurious two-level systems inside the oxide dielectric. We use second order perturbation theory which allows to obtain analytical formulae for the interacting bound states and spectral weights, limited to small and intermediate repulsions. Remarkably, it still reproduces the main features of the model as identified from the Numerical Renormalization Group. We present ...

  4. `Quantum explosion' of a trapped one-dimensional Bose gas

    E-Print Network [OSTI]

    A. S. Campbell; D. M. Gangardt; K. V. Kheruntsyan

    2015-01-15T23:59:59.000Z

    We analyze free expansion of a trapped one-dimensional Bose gas after a sudden release from the confining trap potential. By using the stationary phase and local density approximations, we show that the long-time asymptotic density profile and the momentum distribution of the gas are determined by the initial distribution of Bethe rapidities (quasimomenta) and hence can be obtained from the solutions to the thermodynamic Bethe ansatz equations. For expansion from a harmonic trap, and in the limits of very weak and very strong interactions, we recover the known scaling solutions of the hydrodynamic approach corresponding to self-similar expansion. For all other power-law traps and arbitrary interaction strengths, the expansion is not self-similar and shows strong dependence on the trap anharmonicity of the shape variation of the density profile during evolution. We also characterize dynamical fermionization of an expanding cloud in terms of its first- and second-order coherences describing phase and density fluctuations.

  5. Single Ion Trapping for the Enriched Xenon Observatory

    SciTech Connect (OSTI)

    Waldman, Samuel J.; /Stanford U., Phys. Dept. /SLAC; ,

    2006-03-28T23:59:59.000Z

    In the last decade, a variety of neutrino oscillation experiments have established that there is a mass difference between neutrino flavors, without determining the absolute neutrino mass scale. The Enriched Xenon Observatory for neutrinoless double beta decay (EXO) will search for the rare decays of xenon to determine the absolute value of the neutrino mass. The experiment uses a novel technique to minimize backgrounds, identifying the decay daughter product in real time using single ion spectroscopy. Here, we describe single ion trapping and spectroscopy compatible with the EXO detector. We extend the technique of single ion trapping in ultrahigh vacuum to trapping in xenon gas. With this technique, EXO will achieve a neutrino mass sensitivity of {approx_equal} .010 eV.

  6. Microscale ion trap mass spectrometer

    DOE Patents [OSTI]

    Ramsey, J. Michael (Knoxville, TN); Witten, William B. (Lancing, TN); Kornienko, Oleg (Lansdale, PA)

    2002-01-01T23:59:59.000Z

    An ion trap for mass spectrometric chemical analysis of ions is delineated. The ion trap includes a central electrode having an aperture; a pair of insulators, each having an aperture; a pair of end cap electrodes, each having an aperture; a first electronic signal source coupled to the central electrode; a second electronic signal source coupled to the end cap electrodes. The central electrode, insulators, and end cap electrodes are united in a sandwich construction where their respective apertures are coaxially aligned and symmetric about an axis to form a partially enclosed cavity having an effective radius r.sub.0 and an effective length 2z.sub.0, wherein r.sub.0 and/or z.sub.0 are less than 1.0 mm, and a ratio z.sub.0 /r.sub.0 is greater than 0.83.

  7. Tachyon Physics with Trapped Ions

    E-Print Network [OSTI]

    Lee, Tony E; Cheng, Xiao-Hang; Lamata, Lucas; Solano, Enrique

    2015-01-01T23:59:59.000Z

    It has been predicted that particles with imaginary mass, called tachyons, would be able to travel faster than the speed of light. So far, there has not been any experimental evidence for tachyons in either natural or engineered systems. Here, we propose how to experimentally simulate Dirac tachyons with trapped ions. Quantum measurement on a Dirac particle simulated by a trapped ion causes it to have an imaginary mass so that it may travel faster than the effective speed of light. We show that a Dirac tachyon must have spinor-motion entanglement in order to be superluminal. We also show that it exhibits significantly more Klein tunneling than a normal Dirac particle. We provide numerical simulations with realistic ion systems and show that our scheme is feasible with current technology.

  8. Qualitative analysis of trapped Dirac fermions in graphene

    E-Print Network [OSTI]

    Vit Jakubsky; David Krejcirik

    2014-05-11T23:59:59.000Z

    We study the confinement of Dirac fermions in graphene and in carbon nanotubes by an external magnetic field, mechanical deformations or inhomogeneities in the substrate. By applying variational principles to the square of the Dirac operator, we obtain sufficient and necessary conditions for confinement of the quasi-particles. The rigorous theoretical results are illustrated on the realistic examples of the three classes of traps.

  9. Qualitative analysis of trapped Dirac fermions in graphene

    E-Print Network [OSTI]

    Vit Jakubsky; David Krejcirik

    2015-01-07T23:59:59.000Z

    We study the confinement of Dirac fermions in graphene and in carbon nanotubes by an external magnetic field, mechanical deformations or inhomogeneities in the substrate. By applying variational principles to the square of the Dirac operator, we obtain sufficient and necessary conditions for confinement of the quasi-particles. The rigorous theoretical results are illustrated on the realistic examples of the three classes of traps.

  10. EFFECT OF PORE SIZE ON TRAPPING ZINC VAPORS

    SciTech Connect (OSTI)

    Korinko, P.

    2010-12-17T23:59:59.000Z

    A series of experiments were conducted to determine the effect of pore size on pumping efficiency and zinc vapor trapping efficiency. A simple pumping efficiency test was conducted for all five pore diameters where it was observed that evacuation times were adversely affected by reducing the pore size below 5 {micro}m. Common test conditions for the zinc trapping efficiency experiments were used. These conditions resulted in some variability, to ascribe different efficiencies to the filter media. However, the data suggest that there is no significant difference in trapping efficiency for filter media with pores from 0.2 to 20 {micro}m with a thickness of 0.065-inch. Consequently, the 20 {micro}m pore filter media that is currently used at SRS is a suitable filter material for to utilize for future extractions. There is evidence that smaller pore filter will adversely affect the pumping times for the TEF and little evidence to suggest that a smaller pore diameters have significant impact on the trapping efficiency.

  11. Electromagnetic field generation in the downstream of electrostatic shocks due to electron trapping

    E-Print Network [OSTI]

    Stockem, A; Fonseca, R A; Silva, L O

    2014-01-01T23:59:59.000Z

    A new magnetic field generation mechanism in electrostatic shocks is found, which can produce fields with magnetic energy density as high as 0.01 of the kinetic energy density of the flows on time scales $ \\tilde \\, 10^4 \\, {\\omega}_{pe}^{-1}$. Electron trapping during the shock formation process creates a strong temperature anisotropy in the distribution function, giving rise to the pure Weibel instability. The generated magnetic field is well-confined to the downstream region of the electrostatic shock. The shock formation process is not modified and the features of the shock front responsible for ion acceleration, which are currently probed in laser-plasma laboratory experiments, are maintained. However, such a strong magnetic field determines the particle trajectories downstream and has the potential to modify the signatures of the collisionless shock.

  12. Multi-physics investigation on the failure mechanism and short-time scale wave motion in flip-chip configuration

    E-Print Network [OSTI]

    Oh, Yoonchan

    2005-11-01T23:59:59.000Z

    scale package of 2 Watts steady state power is subjected to 1000 Watts for about 1 ms, junction temperature was seen to rise 50 o C. Mercado et al. [29] did an integrated transient thermal and mechanical analysis for a molded plastic ball grid array...

  13. Electron Trapping by Molecular Vibration

    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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsing Zirconia Nanoparticles as Selective Sorbents .Isotopes (INElectron Trapping by

  14. Electron Trapping by Molecular Vibration

    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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsing Zirconia Nanoparticles as Selective Sorbents .Isotopes (INElectron Trapping

  15. Capturing Energy Savings with Steam Traps

    E-Print Network [OSTI]

    Bockwinkel, R. G.; French, S. A.

    Capturing Energy Savings with Steam Traps Richard C; Bockwinkel General Manager Armstrong Service? A Division of Armstrong International, Inc. Orlando, Florida ABSTRACT This paper will discuss the energy savings potential of steam... Engineer Steam Traps Armstrong International, Inc. Three Rivers, Michigan basis. Finally, it's important to recognize that a steam trap program will reduce steam waste> which will reduce the amount of fuel burned> which will reduce pollutants...

  16. Quantum-enhanced deliberation of learning agents using trapped ions

    E-Print Network [OSTI]

    Vedran Dunjko; Nicolai Friis; Hans J. Briegel

    2015-01-31T23:59:59.000Z

    A scheme that successfully employs quantum mechanics in the design of autonomous learning agents has recently been reported in the context of the projective simulation (PS) model for artificial intelligence. In that approach, the key feature of a PS agent, a specific type of memory which is explored via random walks, was shown to be amenable to quantization. In particular, classical random walks were substituted by Szegedy-type quantum walks, allowing for a speed-up. In this work we propose how such classical and quantum agents can be implemented in systems of trapped ions. We employ a generic construction by which the classical agents are `upgraded' to their quantum counterparts by nested coherent controlization, and we outline how this construction can be realized in ion traps. Our results provide a flexible modular architecture for the design of PS agents. Furthermore, we present numerical simulations of simple PS agents which analyze the robustness of our proposal under certain noise models.

  17. Plant View On Reducing Steam Trap Energy Loss

    E-Print Network [OSTI]

    Vallery, S. J.

    1982-01-01T23:59:59.000Z

    of the steam traps are passing excess steam. This is caused by neglect of aged steam traps which have worn out and misapplication of steam traps by oversizing or using the 'wrong' type trap. Elimination of steam wastes by an effective well engineered steam trap...

  18. Physical Mechanisms of Interaction of Cold Plasma with Polymer Surfaces

    E-Print Network [OSTI]

    Bormashenko, Edward; Multanen, Victor; Shulzinger, Evgeny; Chaniel, Gilad

    2015-01-01T23:59:59.000Z

    Physical mechanisms of the interaction of cold plasmas with organic surfaces are discussed. Trapping of plasma ions by the CH2 groups of polymer surfaces resulting in their electrical charging is treated. Polyethylene surfaces were exposed to the cold radiofrequency air plasma for different intervals of time. The change in the wettability of these surfaces was registered. The experimentally established characteristic time scales of the interaction of cold plasma with polymer surfaces are inversely proportional to the concentration of ions. The phenomenological kinetic model of the electrical charging of polymer surfaces by plasmas is introduced and analyzed.

  19. The Development of a Detailed Chemical Kinetic Mechanism for Diisobutylene and Comparison to Shock Tube Ignition Times

    SciTech Connect (OSTI)

    Metcalfe, W; Curran, H J; Simmie, J M; Pitz, W J; Westbrook, C K

    2005-01-21T23:59:59.000Z

    There is much demand for chemical kinetic models to represent practical fuels such as gasoline, diesel and aviation fuel. These blended fuels contain hundreds of components whose identity and amounts are often unknown. A chemical kinetic mechanism that would represent the oxidation of all these species with accompanying chemical reactions is intractable with current computational capabilities, chemical knowledge and manpower resources. The use of surrogate fuels is an approach to make the development of chemical kinetic mechanisms for practical fuels tractable. A surrogate fuel model consists of a small number of fuel components that can be used to represent the practical fuel and still predict desired characteristics of the practical fuel. These desired fuel characteristics may include ignition behavior, burning velocity, fuel viscosity, fuel vaporization, and fuel emissions (carbon monoxide, hydrocarbons, soot and nitric oxides). Gasoline consists of many different classes of hydrocarbons including n-alkanes, alkenes, iso-alkanes, cycloalkanes, cycloalkenes, and aromatics. One approach is to use a fuel surrogate that has a single component from each class of hydrocarbon in gasoline so that the unique molecular structure of each class is represented. This approach may lead to reliable predictions of many of the combustion properties of the practical fuel. In order to obtain a fuel surrogate mechanism, detailed chemical kinetic mechanisms must be developed for each component in the surrogate. In this study, a detailed chemical kinetic mechanism is developed for diisobutylene, a fuel intended to represent alkenes in practical fuels such as gasoline, diesel, and aviation fuel. The fuel component diisobutylene usually consists of a mixture of two conjugate olefins of iso-octane: 1- or 2-pentene, 2,4,4-trimethyl. Diisobutylene has a similar molecular structure to iso-octane, so that its kinetics offers insight into the effect of including a double bond in the carbon skeletal structure of iso-octane. There are few previous studies on diisobutylene. Kaiser et al. [1] examined the exhaust emission from a production spark ignition engine with neat diisobutylene and with it mixed with gasoline. They found the exhaust emissions of diisobutylene to be similar to that of iso-octane. They saw a significant increase in the amount of 2-methyl-1,3-butadiene measured in the exhaust of the engine. They also found appreciable amount of propene in the exhaust, but could not explain the source of this product as they did others in terms of C-C bond beta scission of alkyl radicals. Risberg et al. [2] studied a number of fuel blends to evaluate their autoignition quality for use in a homogeneous charge compression ignition engine, using diisobutylene to represent olefins in one of their test fuels. In this study, experiments on the shock tube ignition of both isomers of diisobutylene will be described. Then, the development of a detailed chemical kinetic mechanism for the two isomers of diisobutylene will be discussed.

  20. Saving Money with Steam Leak and Steam Trap Surveys

    E-Print Network [OSTI]

    Woodruff, D.

    2010-01-01T23:59:59.000Z

    -sonic equipment. o Having uncorrected steam leaks and faulty traps cost your businesses time and money as well as being environmentally unfriendly. SERVICES ? Air Leak Surveys ? Nitrogen Leak Surveys ?Gas Leak Survey (H2, O2, Natural Gas) ? Steam Leak... productivity ? Processing efficiency ?Provide recommendations for improvement ?Stop profit loss by conserving wasted energy Undetected Steam leaks ? Rob efficiency in manufacturing and processing ? Lose millions of dollars annually ? Add up to very costly...

  1. Rare-earth neutral metal injection into an electron beam ion trap plasma

    SciTech Connect (OSTI)

    Magee, E. W., E-mail: magee1@llnl.gov; Beiersdorfer, P.; Brown, G. V. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Hell, N. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Dr. Remeis-Sternwarte and ECAP, Universität Erlangen-Nürnberg, 96049 Bamberg (Germany)

    2014-11-15T23:59:59.000Z

    We have designed and implemented a neutral metal vapor injector on the SuperEBIT high-energy electron beam ion trap at the Lawrence Livermore National Laboratory. A horizontally directed vapor of a europium metal is created using a thermal evaporation technique. The metal vapor is then spatially collimated prior to injection into the trap. The source's form and quantity constraints are significantly reduced making plasmas out of metal with vapor pressures ?10{sup ?7} Torr at ?1000?°C more obtainable. A long pulsed or constant feed metal vapor injection method adds new flexibility by varying the timing of injection and rate of material being introduced into the trap.

  2. Optical trapping and rotation of airborne absorbing particles with a single focused laser beam

    SciTech Connect (OSTI)

    Lin, Jinda; Li, Yong-qing, E-mail: liy@ecu.edu [Department of Physics, East Carolina University, Greenville, North Carolina 27858-4353 (United States)] [Department of Physics, East Carolina University, Greenville, North Carolina 27858-4353 (United States)

    2014-03-10T23:59:59.000Z

    We measure the periodic circular motion of single absorbing aerosol particles that are optically trapped with a single focused Gaussian beam and rotate around the laser propagation direction. The scattered light from the trapped particle is observed to be directional and change periodically at 0.4–20?kHz. The instantaneous positions of the moving particle within a rotation period are measured by a high-speed imaging technique using a charge coupled device camera and a repetitively pulsed light-emitting diode illumination. The centripetal acceleration of the trapped particle as high as ?20 times the gravitational acceleration is observed and is attributed to the photophoretic forces.

  3. Escaping the poverty trap: modeling the interplay between economic growth and the ecology of infectious disease

    E-Print Network [OSTI]

    Goerg, Georg M; Hébert-Dufresne, Laurent; Althouse, Benjamin M

    2013-01-01T23:59:59.000Z

    The dynamics of economies and infectious disease are inexorably linked: economic well-being influences health (sanitation, nutrition, treatment capacity, etc.) and health influences economic well-being (labor productivity lost to sickness and disease). Often societies are locked into ``poverty traps'' of poor health and poor economy. Here, using a simplified coupled disease-economic model with endogenous capital growth we demonstrate the formation of poverty traps, as well as ways to escape them. We suggest two possible mechanisms of escape both motivated by empirical data: one, through an influx of capital (development aid), and another through changing the percentage of GDP spent on healthcare. We find that a large influx of capital is successful in escaping the poverty trap, but increasing health spending alone is not. Our results demonstrate that escape from a poverty trap may be possible, and carry important policy implications in the world-wide distribution of aid and within-country healthcare spending.

  4. Laser cooling of trapped ions Jurgen Eschner

    E-Print Network [OSTI]

    Blatt, Rainer

    of the art is reported, and several new cooling techniques are outlined. The principles of ion trapping by elucidating several milestone experiments. In addition, a number of special cooling techniques pertainingLaser cooling of trapped ions Ju¨rgen Eschner Institut fu¨ r Experimentalphysik, Universita

  5. Cooling methods in ion traps' Wayne M. Itano, J. C. Bergquist, J. J. Bollinger, D. J. Wineland

    E-Print Network [OSTI]

    techniques, be- cause the ions can be held for long periods in a well- controlled environment. Cooling special cooling techniques. As long as the ions are confined in the trap, they are also confinedCooling methods in ion traps' Wayne M. Itano, J. C. Bergquist, J. J. Bollinger, D. J. Wineland Time

  6. Trapping atoms using nanoscale quantum vacuum forces

    E-Print Network [OSTI]

    D. E. Chang; K. Sinha; J. M. Taylor; H. J. Kimble

    2013-10-22T23:59:59.000Z

    Quantum vacuum forces dictate the interaction between individual atoms and dielectric surfaces at nanoscale distances. For example, their large strengths typically overwhelm externally applied forces, which makes it challenging to controllably interface cold atoms with nearby nanophotonic systems. Here, we show that it is possible to tailor the vacuum forces themselves to provide strong trapping potentials. The trapping scheme takes advantage of the attractive ground state potential and adiabatic dressing with an excited state whose potential is engineered to be resonantly enhanced and repulsive. This procedure yields a strong metastable trap, with the fraction of excited state population scaling inversely with the quality factor of the resonance of the dielectric structure. We analyze realistic limitations to the trap lifetime and discuss possible applications that might emerge from the large trap depths and nanoscale confinement.

  7. Dynamical density functional theory with hydrodynamic interactions and colloids in unstable traps

    E-Print Network [OSTI]

    M. Rex; H. Loewen

    2008-03-13T23:59:59.000Z

    A density functional theory for colloidal dynamics is presented which includes hydrodynamic interactions between the colloidal particles. The theory is applied to the dynamics of colloidal particles in an optical trap which switches periodically in time from a stable to unstable confining potential. In the absence of hydrodynamic interactions, the resulting density breathing mode, exhibits huge oscillations in the trap center which are almost completely damped by hydrodynamic interactions. The predicted dynamical density fields are in good agreement with Brownian dynamics computer simulations.

  8. Theoretical investigation of energy-trapping mechanism by atomic systems

    E-Print Network [OSTI]

    Srivastava, Rajendra P.

    1978-06-01T23:59:59.000Z

    The theoretical results are presented here in detail for the atomic device proposed earlier by the author. This device absorbs energy from a continuous radiation source and stores some of it with atoms in metastable states ...

  9. Investigation of Aging Mechanisms in Lean NOx Traps

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

    2.0 2.5 12 16 20 24 Tim e (s) H 2 concentration (%) In Cat 0.25 Cat 0.50 Cat Out Cat High water-gas shift activity of 30-100 results in greatly increased H 2 production compared to...

  10. Hydrogen trapping in bearing steels: mechanisms and alloy design

    E-Print Network [OSTI]

    Szost, Blanka Angelika

    2013-02-05T23:59:59.000Z

    Hydrogen embrittlement is a problem that offers challenges both to technology and to the theory of metallurgy. In the presence of a hydrogen rich environment, applications such as rolling bearings display a significant decrease in alloy strength...

  11. Benchmark Reaction Mechanisms and Kinetics for Lean NOx Traps | Department

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarly Career Scientists' ResearchTheMarketing,Energy and Natural Resources By:Commerce|Science,

  12. Benchmark Reaction Mechanisms and Kinetics for Lean NOx Traps | Department

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-Up fromDepartmentTie Ltd: ScopeDepartment ofEnergy Victorof Energy Presentationof

  13. Fuel traps: mapping stability via water association.

    SciTech Connect (OSTI)

    Rempe, Susan L.; Clawson, Jacalyn S.; Greathouse, Jeffery A.; Alam, Todd M; Leung, Kevin; Varma, Sameer; Sabo, Dubravko; Martin, Marcus Gary; Cygan, Randall Timothy

    2007-03-01T23:59:59.000Z

    Hydrogen storage is a key enabling technology required for attaining a hydrogen-based economy. Fundamental research can reveal the underlying principles controlling hydrogen uptake and release by storage materials, and also aid in characterizing and designing novel storage materials. New ideas for hydrogen storage materials come from exploiting the properties of hydrophobic hydration, which refers to water s ability to stabilize, by its mode of association, specific structures under specific conditions. Although hydrogen was always considered too small to support the formation of solid clathrate hydrate structures, exciting new experiments show that water traps hydrogen molecules at conditions of low temperatures and moderate pressures. Hydrogen release is accomplished by simple warming. While these experiments lend credibility to the idea that water could form an environmentally attractive alternative storage compound for hydrogen fuel, which would advance our nation s goals of attaining a hydrogen-based economy, much work is yet required to understand and realize the full potential of clathrate hydrates for hydrogen storage. Here we undertake theoretical studies of hydrogen in water to establish a firm foundation for predictive work on clathrate hydrate H{sub 2} storage capabilities. Using molecular simulation and statistical mechanical theories based in part on quantum mechanical descriptions of molecular interactions, we characterize the interactions between hydrogen and liquid water in terms of structural and thermodynamic properties. In the process we validate classical force field models of hydrogen in water and discover new features of hydrophobic hydration that impact problems in both energy technology and biology. Finally, we predict hydrogen occupancy in the small and large cages of hydrogen clathrate hydrates, a property unresolved by previous experimental and theoretical work.

  14. In-situ, Real-Time Monitoring of Mechanical and Chemical Structure Changes in a V2O5 Battery Electrode Using a MEMS Optical Sensor

    SciTech Connect (OSTI)

    Jung, H. [University of Maryland; Gerasopoulos, K. [University of Maryland; Gnerlich, Markus [University of Maryland; Talin, A. Alec [Sandia National Laboratories; Ghodssi, Reza [University of Maryland

    2014-06-01T23:59:59.000Z

    This work presents the first demonstration of a MEMS optical sensor for in-situ, real-time monitoring of both mechanical and chemical structure evolutions in a V2O5 lithium-ion battery (LIB) cathode during battery operation. A reflective membrane forms one side of a Fabry-Perot (FP) interferometer, while the other side is coated with V2O5 and exposed to electrolyte in a half-cell LIB. Using one microscope and two laser sources, both the induced membrane deflection and the corresponding Raman intensity changes are observed during lithium cycling. Results are in good agreement with the expected mechanical behavior and disorder change of the V2O5 layers, highlighting the significant potential of MEMS as enabling tools for advanced scientific investigations.

  15. Charge Trapping in High Efficiency Alternating Copolymers: Implication...

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

    Charge Trapping in High Efficiency Alternating Copolymers: Implications in Organic Photovoltaic Device Efficiency Home > Research > ANSER Research Highlights > Charge Trapping in...

  16. atom trap trace: Topics by E-print Network

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

    1 An atom trap trace analysis system for measuring krypton contamination in xenon dark matter detectors Physics Websites Summary: An atom trap trace analysis system for measuring...

  17. Microfabricated Renewable Beads-Trapping/Releasing Flow Cell...

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

    Microfabricated Renewable Beads-TrappingReleasing Flow Cell for Rapid Antigen-Antibody Reaction in Chemiluminescent Immunoassay Microfabricated Renewable Beads-TrappingReleasing...

  18. Lean NOx Traps - Microstructural Studies of Real World and Model...

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

    Traps - Microstructural Studies of Real World and Model Catalysts Lean NOx Traps - Microstructural Studies of Real World and Model Catalysts 2005 Diesel Engine Emissions Reduction...

  19. Requirements-Driven Diesel Catalyzed Particulate Trap Design...

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

    Requirements-Driven Diesel Catalyzed Particulate Trap Design and Optimization Requirements-Driven Diesel Catalyzed Particulate Trap Design and Optimization 2005 Diesel Engine...

  20. Characterization of Trapped Lignin-Degrading Microbes in Tropical...

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

    Trapped Lignin-Degrading Microbes in Tropical Forest Soil. Characterization of Trapped Lignin-Degrading Microbes in Tropical Forest Soil. Abstract: Lignin is often the most...

  1. H2-Assisted NOx Traps: Test Cell Results Vehicle Installations...

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

    H2-Assisted NOx Traps: Test Cell Results Vehicle Installations H2-Assisted NOx Traps: Test Cell Results Vehicle Installations 2003 DEER Conference Presentation: ArvinMeritor...

  2. The time as an emergent property of quantum mechanics, a synthetic description of a first experimental approach

    E-Print Network [OSTI]

    E Moreva; G Brida; M Gramegna; V Giovannetti; L Maccone; M Genovese

    2015-02-11T23:59:59.000Z

    The "problem of time" in present physics substantially consists in the fact that a straightforward quantization of the general relativistic evolution equation and constraints generates for the Universe wave function the Wheeler-De Witt equation, which describes a static Universe. Page and Wootters considered the fact that there exist states of a system composed by entangled subsystems that are stationary, but one can interpret the component subsystems as evolving: this leads them to suppose that the global state of the universe can be envisaged as one of this static entangled state, whereas the state of the subsystems can evolve. Here we synthetically present an experiment, based on PDC polarization entangled photons, that allows showing with a practical example a situation where this idea works, i.e. a subsystem of an entangled state works as a "clock" of another subsystem.

  3. An Atom Trap Relying on Optical Pumping

    E-Print Network [OSTI]

    P. Bouyer; P. Lemonde; M. Ben Dahan; A. Michaud; C. Salomon; J. Dalibard

    2005-09-21T23:59:59.000Z

    We have investigated a new radiation pressure trap which relies on optical pumping and does not require any magnetic field. It employs six circularly polarized divergent beams and works on the red of a $J_{g} \\longrightarrow J_{e} = J_{g} + 1$ atomic transition with $J_{g} \\geq 1/2$. We have demonstrated this trap with cesium atoms from a vapour cell using the 852 nm $J_{g} = 4 \\longrightarrow J_{e} = 5$ resonance transition. The trap contained up to $3 \\cdot 10^{7}$ atoms in a cloud of $1/\\sqrt{e}$ radius of 330 $\\mu$m.

  4. Steam Trap Maintenance as a Profit Center

    E-Print Network [OSTI]

    Bouchillon, J. L.

    the Eighteenth Industrial Energy Technology Conference, Houston, TX, April 17-18, 1996 EXCUSES Everybody thinks his or her steam trap maintenance is good. Surveysl have shown the following are the most popular excuses encountered when managers are confronted... for steam traps. 192 ESL-IE-96-04-28 Proceedings from the Eighteenth Industrial Energy Technology Conference, Houston, TX, April 17-18, 1996 5. Set up a trap maintenance program C. Prepare and present a report to that will: management on the results...

  5. Nuclear spin qubits in a trapped-ion quantum computer

    E-Print Network [OSTI]

    M. Feng; Y. Y. Xu; F. Zhou; D. Suter

    2009-04-26T23:59:59.000Z

    Physical systems must fulfill a number of conditions to qualify as useful quantum bits (qubits) for quantum information processing, including ease of manipulation, long decoherence times, and high fidelity readout operations. Since these conditions are hard to satisfy with a single system, it may be necessary to combine different degrees of freedom. Here we discuss a possible system, based on electronic and nuclear spin degrees of freedom in trapped ions. The nuclear spin yields long decoherence times, while the electronic spin, in a magnetic field gradient, provides efficient manipulation, and the optical transitions of the ions assure a selective and efficient initialization and readout.

  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. Novel light trapping scheme for thin crystalline cells utilizing deep structures on both wafer sides

    SciTech Connect (OSTI)

    Jorgensen, A.M.; Clausen, T.; Leistiko, O. [Technical Univ. of Denmark, Lyngby (Denmark). Microelectronics Centre

    1997-12-31T23:59:59.000Z

    A new light trapping structure is presented with trapping capabilities comparable to or better than those of the perpendicular grooves structure. The new structure traps a larger fraction of rays for 8--80 passes than the perpendicular grooves structure. The average path length enhancement is about 62 times the average thickness. The structure consists of deep ({approximately}200 {micro}m) inverted pyramids on the front side and deep ({approximately}200 {micro}m) truncated pyramids with eight sides on the back. The structure is realized in crystalline silicon by wet chemical etching using potassium hydroxide (KOH) and isopropanol (IPA). A process for creating thin solar cells with this light trapping scheme is described. The process includes only two main photolithographic steps and features a self aligned front metallization. The process uses 250 {micro}m wafers to create cells that on average are about 70 {micro}m thick.

  8. A quantum information processor with trapped ions

    E-Print Network [OSTI]

    Schindler, Philipp

    Quantum computers hold the promise to solve certain problems exponentially faster than their classical counterparts. Trapped atomic ions are among the physical systems in which building such a computing device seems viable. ...

  9. pH-biased isoelectric trapping separations

    E-Print Network [OSTI]

    Shave, Evan Eric

    2006-10-30T23:59:59.000Z

    The classical isoelectric trapping (IET) technique, using the multicompartment electrolyzer (MCE), has been one of the most successful electrophoretic techniques in preparative-scale protein separations. IET is capable of achieving high resolution...

  10. Use of Bullet Traps and Steel Targets

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

    design criteria and deployment specifications of bullet traps on U.S. Department of Energy (DOE) live-fire ranges. Deviation from these design and deployment criteria must be...

  11. Energy Savings Through Steam Trap Management

    E-Print Network [OSTI]

    Gibbs, C.

    2008-01-01T23:59:59.000Z

    Energy Savings through Steam Trap Management Chris Gibbs, Account Manager, Armstrong International, Inc., Three Rivers, MI ESL-IE-08-05-08 Proceedings from theThirtieth Industrial Energy Technology Conference...-based steam trap management application developed by Armstrong International. The application calculates steam loss, fuel loss, dollar loss and CO 2 emission generation. The database allows for trend analysis, automatic energy report generation...

  12. Exchange of deeply trapped and interstitial hydrogen in silicon Blair Tuttle

    E-Print Network [OSTI]

    Adams, James B

    Exchange of deeply trapped and interstitial hydrogen in silicon Blair Tuttle Department of Physics Engineering, Arizona State University, Tempe, Arizona 85287-6006 Received 22 May 1998; revised manuscript mechanisms between an interstitial hydrogen atom and a deeply bound H at a silicon-hydrogen bond. We

  13. On the Mechanical Interaction of Light With Homogeneous Liquids

    E-Print Network [OSTI]

    de Reus, Michiel

    2013-01-01T23:59:59.000Z

    We investigate one of the consequences of the three competing models describing the mechanical interaction of light with a dielectric medium. According to both the Abraham and Minkowski models the time-averaged force density is zero inside a homogeneous dielectric, whereas the induced-current Lorentz force model predicts a non-zero force density. We argue that the latter force, if exists, could drive a hydrodynamic flow inside a homogeneous fluid. Our numerical experiments show that such flows have distinct spatial patterns and may influence the dynamics of particles in a water-based single-beam optical trap.

  14. Mobility and trapping of hydrogen in high-strength steel Vucko Flavien, Aoufi Asdin, Bosch Cdric, Delafosse David,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    detrimental to the mechanical properties of steels [1,2]. The sensitivity to hydrogen embrittlement increases are due to the presence of hydrogen. Hydrogen embrittlement mechanisms are closely linked to the mobilityMobility and trapping of hydrogen in high-strength steel Vucko Flavien, Aoufi Asdin, Bosch Cédric

  15. Transport of ions in a segmented linear Paul trap in printed-circuit-board technology

    E-Print Network [OSTI]

    G. Huber; T. Deuschle; W. Schnitzler; R. Reichle; K. Singer; F. Schmidt-Kaler

    2007-11-19T23:59:59.000Z

    We describe the construction and operation of a segmented linear Paul trap, fabricated in printed-circuit-board technology with an electrode segment width of 500 microns. We prove the applicability of this technology to reliable ion trapping and report the observation of Doppler cooled ion crystals of Ca-40 with this kind of traps. Measured trap frequencies agree with numerical simulations at the level of a few percent from which we infer a high fabrication accuracy of the segmented trap. To demonstrate its usefulness and versatility for trapped ion experiments we study the fast transport of a single ion. Our experimental results show a success rate of 99.0(1)% for a transport distance of 2x2mm in a round-trip time of T=20us, which corresponds to 4 axial oscillations only. We theoretically and experimentally investigate the excitation of oscillations caused by fast ion transports with error-function voltage ramps: For a slightly slower transport (a round-trip shuttle within T=30us) we observe non-adiabatic motional excitation of 0.89(15)meV.

  16. Loading of a surface electrode ion trap from a remote, pre-cooled source

    E-Print Network [OSTI]

    Sage, Jeremy M; Chiaverini, John

    2012-01-01T23:59:59.000Z

    We demonstrate for the first time the loading of ions into a surface electrode trap (SET) from a remote, laser-cooled source of neutral atoms. We first cool and load $\\sim$ $10^6$ neutral $^{88}$Sr atoms into a magneto-optical trap (MOT) from an oven that has no line-of-sight with the SET. The cold atoms are then pushed with a resonant laser into the trap region where they are subsequently photoionized and trapped in an SET operated at a cryogenic temperature of 4.6 K. We present studies of the loading process and show that our technique achieves ion loading into a shallow (15 meV depth) trap at rates as high as 125 ions/s while drastically reducing the amount of deposition of metal on the trap surface as compared with direct loading from a hot vapor. Furthermore, we note that due to multiple stages of isotopic filtering in our loading process, this technique has enhanced isotopic selectivity over other loading methods. Rapid loading from a clean, isotopically pure, and pre-cooled source will potentially enab...

  17. Photonic assisted light trapping integrated in ultrathin crystalline silicon solar cells by nanoimprint lithography

    E-Print Network [OSTI]

    Trompoukis, Christos; Depauw, Valérie; Gordon, Ivan; Poortmans, Jef; 10.1063/1.4749810.

    2012-01-01T23:59:59.000Z

    We report on the fabrication of two-dimensional periodic photonic nanostructures by nanoimprint lithography and dry etching, and their integration into a 1-{\\mu}m-thin mono-crystalline silicon solar cell. Thanks to the periodic nanopatterning, a better in-coupling and trapping of light is achieved, resulting in an absorption enhancement. The proposed light trapping mechanism can be explained as the superposition of a graded index effect and of the diffraction of light inside the photoactive layer. The absorption enhancement is translated into a 23% increase in short-circuit current, as compared to the benchmark cell, resulting in an increase in energy-conversion efficiency.

  18. Scaling of capillary trapping in unstable two-phase flow: Application to CO[subscript 2] sequestration in deep saline aquifers

    E-Print Network [OSTI]

    Szulczewski, Michael L.

    The effect of flow instabilities on capillary trapping mechanisms is a major source of uncertainty in CO2 sequestration in deep saline aquifers. Standard macroscopic models of multiphase flow in porous media are unable to ...

  19. Energy trapping and shock disintegration in a composite granular medium

    E-Print Network [OSTI]

    C. Daraio; V. F. Nesterenko; E. B. Herbold; S. Jin

    2005-09-24T23:59:59.000Z

    Granular materials demonstrate a strongly nonlinear behavior influencing the wave propagation in the medium. We report the first experimental observation of impulse energy confinement and the resultant disintegration of shock and solitary waves. The medium consists of alternating ensambles of high-modulus vs orders of magnitude lower modulus chains of different masses. The trapped energy is contained within the "softer" portions of the composite chain and is slowly released in the form of weak, separated pulses over an extended period of time. This effect is enhanced by using a specific group assembly and superimposed force.

  20. Superconducting qubits can be coupled and addressed as trapped ions

    E-Print Network [OSTI]

    Yu-xi Liu; L. F. Wei; J. R. Johansson; J. S. Tsai; Franco Nori

    2007-11-20T23:59:59.000Z

    Exploiting the intrinsic nonlinearity of superconducting Josephson junctions, we propose a scalable circuit with superconducting qubits (SCQs) which is very similar to the successful one now being used for trapped ions. The SCQs are coupled to the "vibrational" mode provided by a superconducting LC circuit or its equivalent (e.g., a SQUID). Both single-qubit rotations and qubit-LC-circuit couplings/decouplings can be controlled by the frequencies of the time-dependent magnetic fluxes. The circuit is scalable since the qubit-qubit interactions, mediated by the LC circuit, can be selectively performed, and the information transfer can be realized in a controllable way.

  1. Ball-grid array architecture for microfabricated ion traps

    E-Print Network [OSTI]

    Nicholas D. Guise; Spencer D. Fallek; Kelly E. Stevens; K. R. Brown; Curtis Volin; Alexa W. Harter; Jason M. Amini; Robert E. Higashi; Son Thai Lu; Helen M. Chanhvongsak; Thi A. Nguyen; Matthew S. Marcus; Thomas R. Ohnstein; Daniel W. Youngner

    2014-12-19T23:59:59.000Z

    State-of-the-art microfabricated ion traps for quantum information research are approaching nearly one hundred control electrodes. We report here on the development and testing of a new architecture for microfabricated ion traps, built around ball-grid array (BGA) connections, that is suitable for increasingly complex trap designs. In the BGA trap, through-substrate vias bring electrical signals from the back side of the trap die to the surface trap structure on the top side. Gold-ball bump bonds connect the back side of the trap die to an interposer for signal routing from the carrier. Trench capacitors fabricated into the trap die replace area-intensive surface or edge capacitors. Wirebonds in the BGA architecture are moved to the interposer. These last two features allow the trap die to be reduced to only the area required to produce trapping fields. The smaller trap dimensions allow tight focusing of an addressing laser beam for fast single-qubit rotations. Performance of the BGA trap as characterized with $^{40}$Ca$^+$ ions is comparable to previous surface-electrode traps in terms of ion heating rate, mode frequency stability, and storage lifetime. We demonstrate two-qubit entanglement operations with $^{171}$Yb$^+$ ions in a second BGA trap.

  2. Signal enhancement using a switchable magnetic trap

    DOE Patents [OSTI]

    Beer, Neil Reginald (Pleasanton, CA)

    2012-05-29T23:59:59.000Z

    A system for analyzing a sample including providing a microchannel flow channel; associating the sample with magnetic nanoparticles or magnetic polystyrene-coated beads; moving the sample with said magnetic nanoparticles or magnetic polystyrene-coated beads in the microchannel flow channel; holding the sample with the magnetic nanoparticles or magnetic polystyrene-coated beads in a magnetic trap in the microchannel flow channel; and analyzing the sample obtaining an enhanced analysis signal. An apparatus for analysis of a sample includes magnetic particles connected to the sample, a microchip, a flow channel in the microchip, a source of carrier fluid connected to the flow channel for moving the sample in the flow channel, an electromagnet trap connected to the flow line for selectively magnetically trapping the sample and the magnetic particles, and an analyzer for analyzing the sample.

  3. Enhanced Raman sideband cooling of caesium atoms in a vapour-loaded magneto-optical trap

    E-Print Network [OSTI]

    Li, Y; Feng, G; Nute, J; Piano, S; Hackermuller, L; Ma, J; Xiao, L; Jia, S

    2015-01-01T23:59:59.000Z

    We report enhanced three-dimensional degenerated Raman sideband cooling (3D DRSC) of caesium (Cs) atoms in a standard single-cell vapour-loading magneto-optical trap. Our improved scheme involves using a separate repumping laser and optimized lattice detuning. We load $1.5 \\times 10^7$ atoms into the Raman lattice with a detuning of -15.5 GHz (to the ground F = 3 state). Enhanced 3D DRSC is used to cool them from 60 $\\mu$K to 1.7 $\\mu$K within 12 ms and the number of obtained atoms is about $1.2 \\times 10^7$. A theoretical model is proposed to simulate the measured number of trapped atoms. The result shows good agreement with the experimental data. The technique paves the way for loading a large number of ultracold Cs atoms into a crossed dipole trap and efficient evaporative cooling in a single-cell system.

  4. Thermal electric vapor trap arrangement and method

    DOE Patents [OSTI]

    Alger, T.

    1988-03-15T23:59:59.000Z

    A technique for trapping vapor within a section of a tube is disclosed herein. This technique utilizes a conventional, readily providable thermal electric device having a hot side and a cold side and means for powering the device to accomplish this. The cold side of this device is positioned sufficiently close to a predetermined section of the tube and is made sufficiently cold so that any condensable vapor passing through the predetermined tube section is condensed and trapped, preferably within the predetermined tube section itself. 4 figs.

  5. Physical process Mechanical mechanisms

    E-Print Network [OSTI]

    Berlin,Technische Universität

    1 Physical process Generation · Mechanical mechanisms F = m·a · Electric/Magnetic mechanisms F ­ Quadrupoles......shear stress fluctuations ­ High order poles...... phys. interpretation difficult Governing

  6. Characterization of Trapped Lignin-Degrading Microbes in Tropical Forest Soil

    E-Print Network [OSTI]

    DeAngelis, Kristen

    2012-01-01T23:59:59.000Z

    Characterization of Trapped Lignin-Degrading Microbes inCharacterization of Trapped Lignin-Degrading Microbes inCharacterization of Trapped Lignin-Degrading Microbes in

  7. Quantum Stochastic Heating of a Trapped Ion

    E-Print Network [OSTI]

    L. Horvath; R. Fisher; M. J. Collett; H. J. Carmichael

    2007-11-09T23:59:59.000Z

    The resonant heating of a harmonically trapped ion by a standing-wave light field is described as a quantum stochastic process combining a coherent Schroedinger evolution with Bohr-Einstein quantum jumps. Quantum and semi-quantum treatments are compared.

  8. Energy Conservation Thru Steam Trap Surveys and Preventive Maintenance Programs

    E-Print Network [OSTI]

    Boynton, T.; Dewhirst, B.

    1980-01-01T23:59:59.000Z

    ENERGY CONSERVATION THRU STEAM TRAP SURVEYS AND PREVENTIVE MAINTENANCE PROGRAMS Terry Boynton, Armstrong, Three Rivers, Mich. Bob Dewhirst, Armstrong, New Braunfels, Texas. This paper will deal with steam trap surveys and preventive maintenance...

  9. Effective Steam Trap Selection/Maintenance - Its Payback

    E-Print Network [OSTI]

    Garcia, E.

    1984-01-01T23:59:59.000Z

    In oil refineries and petrochemical plants large number of steam traps are used to discharge condensate from steam mains, tracers and process equipment. Early efforts on steam traps focused almost exclusively on their selection and sizing...

  10. In-Vacuum Active Electronics for Microfabricated Ion Traps

    E-Print Network [OSTI]

    Nicholas D. Guise; Spencer D. Fallek; Harley Hayden; C-S Pai; Curtis Volin; K. R. Brown; J. True Merrill; Alexa W. Harter; Jason M. Amini; Lisa M. Lust; Kelly Muldoon; Doug Carlson; Jerry Budach

    2014-06-02T23:59:59.000Z

    The advent of microfabricated ion traps for the quantum information community has allowed research groups to build traps that incorporate an unprecedented number of trapping zones. However, as device complexity has grown, the number of digital-to-analog converter (DAC) channels needed to control these devices has grown as well, with some of the largest trap assemblies now requiring nearly one hundred DAC channels. Providing electrical connections for these channels into a vacuum chamber can be bulky and difficult to scale beyond the current numbers of trap electrodes. This paper reports on the development and testing of an in-vacuum DAC system that uses only 9 vacuum feedthrough connections to control a 78-electrode microfabricated ion trap. The system is characterized by trapping single and multiple $^{40}$Ca$^+$ ions. The measured axial mode stability, ion heating rates, and transport fidelities for a trapped ion are comparable to systems with external(air-side) commercial DACs.

  11. Towards a cryogenic planar ion trap for Sr-88

    E-Print Network [OSTI]

    Bakr, Waseem (Waseem S.)

    2006-01-01T23:59:59.000Z

    This thesis describes experiments with ion traps constructed with electrodes in a single two-dimensional plane, and ion traps operated in a cryogenic environment at 77K and 4K temperatures. These two technologies address ...

  12. Carbon dioxide dissolution in structural and stratigraphic traps

    E-Print Network [OSTI]

    Hesse, M. A.

    The geologic sequestration of carbon dioxide (CO[subscript 2]) in structural and stratigraphic traps is a viable option to reduce anthropogenic emissions. While dissolution of the CO[subscript 2] stored in these traps ...

  13. Nano-photonic Light Trapping In Thin Film Solar Dennis M. Callahan Jr.

    E-Print Network [OSTI]

    Winfree, Erik

    Nano-photonic Light Trapping In Thin Film Solar Cells Thesis by Dennis M. Callahan Jr. In Partial. Jeremy Munday for helping me get started on the thin-film GaAs project and for all the time we spent to thank Dr. Jonathan Grandidier for working closely with me for a couple years on the nano sphere solar

  14. E B UNA-TRAP FISHERY E E ITERRANEAN SEA

    E-Print Network [OSTI]

    of the bag of the trap to concentrate the tuna prior to capture. Photo supplied by Dr. Alonzo Palau, Genova

  15. Entropic Time

    SciTech Connect (OSTI)

    Caticha, Ariel [Department of Physics, University at Albany-SUNY, Albany, NY 12222 (United States)

    2011-03-14T23:59:59.000Z

    The formulation of quantum mechanics within the framework of entropic dynamics includes several new elements. In this paper we concentrate on one of them: the implications for the theory of time. Entropic time is introduced as a book-keeping device to keep track of the accumulation of changes. One new feature is that, unlike other concepts of time appearing in the so-called fundamental laws of physics, entropic time incorporates a natural distinction between past and future.

  16. Dissipative dynamics of a vortex state in a trapped Bose-condensed gas

    E-Print Network [OSTI]

    P. O. Fedichev; G. V. Shlyapnikov

    1999-06-15T23:59:59.000Z

    We discuss dissipative dynamics of a vortex state in a trapped Bose-condensed gas at finite temperature and draw a scenario of decay of this state in a static trap. The interaction of the vortex with the thermal cloud transfers energy from the vortex to the cloud and induces the motion of the vortex core to the border of the condensate. Once the vortex reaches the border, it immediately decays through the creation of excitations. We calculate the characteristic life-time of a vortex state and address the question of how the dissipative dynamics of vortices can be studied experimentally.

  17. Enhancing entanglement trapping by weak measurement and quantum measurement reversal

    E-Print Network [OSTI]

    Ying-Jie Zhang; Wei Han; Heng Fan; Yun-Jie Xia

    2015-01-13T23:59:59.000Z

    In this paper, we propose a scheme to enhance trapping of entanglement of two qubits in the environment of a photonic band gap material. Our entanglement trapping promotion scheme makes use of combined weak measurements and quantum measurement reversals. The optimal promotion of entanglement trapping can be acquired with a reasonable finite success probability by adjusting measurement strengths.

  18. Magnetic trapping of metastable 3 P2 atomic strontium

    E-Print Network [OSTI]

    Killian, Thomas C.

    Magnetic trapping of metastable 3 P2 atomic strontium S. B. Nagel, C. E. Simien, S. Laha, P. Gupta trapping of metastable 3 P2 atomic strontium. Atoms are cooled in a magneto-optical trap MOT operating cooling on such a transition in strontium may lead to a fast and efficient route to all-optical quantum

  19. Photostability of dye molecules trapped in solid matrices

    E-Print Network [OSTI]

    Boyer, Edmond

    Photostability of dye molecules trapped in solid matrices Arnaud Dubois, Michael Canva, Alain Brun, Fre´de´ric Chaput, and Jean-Pierre Boilot The photostability of dye molecules trapped in transparent that different trapped dye molecules can absorb on average before they are bleached. Dyes such as Perylene Red

  20. Fundamental limit of nanophotonic light trapping in solar cells

    E-Print Network [OSTI]

    Fan, Shanhui

    Fundamental limit of nanophotonic light trapping in solar cells Zongfu Yu1 , Aaswath Raman and is becoming increasingly urgent for current solar cell research. The standard theory of light trapping) Establishing the fundamental limit of nanophotonic light-trapping schemes is of paramount importance

  1. First Attempts at Antihydrogen Trapping in G.B. Andresen

    E-Print Network [OSTI]

    Wurtele, Jonathan

    . The ALPHA apparatus is designed to produce and trap antihydrogen atoms. The de- vice comprises OF EACH PAPER CP1037, Cold Antimatter Plasmas and Application to Fundamental Physics, edited by Y. Kanai captured and cooled antiprotons in the catching trap. The catching trap includes a "rotating wall" electric

  2. An optical trap for relativistic plasmaa... Ping Zhang,b)

    E-Print Network [OSTI]

    Umstadter, Donald

    An optical trap for relativistic plasmaa... Ping Zhang,b) Ned Saleh, Shouyuan Chen, Zhengming Sheng November 2002; accepted 14 February 2003 The first optical trap capable of confining relativistic electrons that the optical trap acted to heat electrons, increasing their temperature by two orders of magnitude

  3. Resonance capture by hydrogenous impurities and losses of ultracold neutrons in solid material traps

    E-Print Network [OSTI]

    G. S. Danilov

    2009-03-03T23:59:59.000Z

    The capture of trapped ultracold neutrons (UCNs) by closed hydrogenous impurities within a solid coating of the trap is discussed as a possible cause of observed anomalously large losses of UCNs in solid material UCN traps. Then significant losses of UCNs arise only if resonances occur in the UCN-impurity scattering amplitude. For a large size impurity, higher partial waves in the UCN-impurity interaction are important, and they are taken into account in the present paper. The method of the calculation is applicable to irregular shape impurities as well. A small distortion of an impurity shape, if it splits the resonance, can increase the UCN losses by a few times. UCN losses in the beryllium trap are calculated assuming they are due to the UCN capture by ice spherical impurities within the coating of the trap walls. Both s- and p-wave resonances contribute significantly to the UCN losses considered. As an example, observed anomalous large UCN losses are achieved if the average radius of the impurity is about 600 Angstroms and the impurity density is about 3*10^{14}/cm^3. A distortion of the spherical shape of the impurity could increase the UCN losses and therefore decrease the impurity density.

  4. Quantum Theory of Cavityless Feedback Cooling of An Optically Trapped Nanoparticle

    E-Print Network [OSTI]

    Rodenburg, B; Vamivakas, A N; Bhattacharya, M

    2015-01-01T23:59:59.000Z

    We present a quantum theory of cavityless feedback cooling of an optically trapped harmonically oscillating subwavelength dielectric particle, a configuration recently realized in several experiments. Specifically, we derive a Markovian master equation that treats the mechanical as well as optical degrees of freedom quantum mechanically. Employing this equation, we solve for the nanoparticle phonon number dynamics exactly, and extract analytic expressions for the cooling timescale and the steady state phonon number. We present experimental data verifying the predictions of our model in the classical regime, and also demonstrate that quantum ground state preparation is within reach of ongoing experiments. Our work provides a quantitative framework for future theoretical modeling of the cavityless quantum optomechanics of optically trapped dielectric particles.

  5. Landau damping and the onset of particle trapping in quantum plasmas

    SciTech Connect (OSTI)

    Daligault, Jérôme [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2014-04-15T23:59:59.000Z

    Using analytical theory and simulations, we assess the impact of quantum effects on non-linear wave-particle interactions in quantum plasmas. We more specifically focus on the resonant interaction between Langmuir waves and electrons, which, in classical plasmas, lead to particle trapping. Two regimes are identified depending on the difference between the time scale of oscillation t{sub B}(k)=?(m/eEk) of a trapped electron and the quantum time scale t{sub q}(k)=2m/?k{sup 2} related to recoil effect, where E and k are the wave amplitude and wave vector. In the classical-like regime, t{sub B}(k)?trapped in the wave troughs and greatly affect the evolution of the system long before the wave has had time to Landau damp by a large amount according to linear theory. In the quantum regime, t{sub B}(k)?>?t{sub q}(k), particle trapping is hampered by the finite recoil imparted to resonant electrons in their interactions with plasmons.

  6. Energy Savings with Computerized Steam Trap Maintenance Program

    E-Print Network [OSTI]

    Klidzejs, A. M.

    by Armstrong International, Inc. Five other manufacturers each have about a 5% share of the tmp population, and about 5 more account for the remaining steam traps. 6,430 STEAM TRAPS COLl3Il~) FIGURE 3 - Steam trap population by application. 8,430 STEAM... standardized using the inverted bucket steam trap made by Armstrong International, Inc. "or equal", with approval, wherever applicable and sensible. I believe the inverted bucket steam trap is the best one for this. The selection of a good manufacturer...

  7. Steam Trap Testing and Evaluation: An Actual Plant Case Study

    E-Print Network [OSTI]

    Feldman, A. L.

    1981-01-01T23:59:59.000Z

    on there is a hydraul ic shock in the forn! of a water hammer. The standard trap used at the Olin-Joliet Plant is an Armstrong carbon steel inverted bucket. The hydraulic shock has not only broken the valve assembly on the inverted buckets, but has also... service is what caused the traps to fail closed. The last set of traps tested was the Armstrong 1013LV stainless steel inverted buckets. The capacity of these units required that for each coil two traps in parallel would be required. The traps do...

  8. Trapped surfaces in vacuum arising dynamically from mild incoming radiation

    E-Print Network [OSTI]

    Xinliang An; Jonathan Luk

    2014-09-22T23:59:59.000Z

    In this paper, we study the "minimal requirement" on the incoming radiation that guarantees a trapped surface to form in vacuum. First, we extend the region of existence in Christodoulou's theorem on the formation of trapped surfaces and consequently show that the lower bound required to form a trapped surface can be relaxed. Second, we demonstrate that trapped surfaces form dynamically from a class of initial data which are large merely in a scaling-critical norm. This result is motivated in part by the scaling in Christodoulou's formation of trapped surfaces theorem for the Einstein-scalar field system in spherical symmetry.

  9. An ion trap built with photonic crystal fibre technology

    E-Print Network [OSTI]

    F. Lindenfelser; B. Keitch; D. Kienzler; D. Bykov; P. Uebel; M. A. Schmidt; P. St. J. Russell; J. P. Home

    2015-01-20T23:59:59.000Z

    We demonstrate a surface-electrode ion trap fabricated using techniques transferred from the manufacture of photonic-crystal fibres. This provides a relatively straightforward route for realizing traps with an electrode structure on the 100 micron scale with high optical access. We demonstrate the basic functionality of the trap by cooling a single ion to the quantum ground state, allowing us to measure a heating rate from the ground state of 787(24) quanta/s. Variation of the fabrication procedure used here may provide access to traps in this geometry with trap scales between 100 um and 10 um.

  10. An ion trap built with photonic crystal fibre technology

    E-Print Network [OSTI]

    Lindenfelser, F; Kienzler, D; Bykov, D; Uebel, P; Schmidt, M A; Russell, P St J; Home, J P

    2015-01-01T23:59:59.000Z

    We demonstrate a surface-electrode ion trap fabricated using techniques transferred from the manufacture of photonic-crystal fibres. This provides a relatively straightforward route for realizing traps with an electrode structure on the 100 micron scale with high optical access. We demonstrate the basic functionality of the trap by cooling a single ion to the quantum ground state, allowing us to measure a heating rate from the ground state of 787(24) quanta/s. Variation of the fabrication procedure used here may provide access to traps in this geometry with trap scales between 100 um and 10 um.

  11. Shortcuts to adiabaticity for trapped ultracold gases

    E-Print Network [OSTI]

    Schaff, Jean-François; Labeyrie, Guillaume; Vignolo, Patrizia

    2011-01-01T23:59:59.000Z

    We study, experimentally and theoretically, the controlled transfer of harmonically trapped ultracold gases between different quantum states. In particular we experimentally demonstrate a fast decompression and displacement of both a non-interacting gas and an interacting Bose-Einstein condensate which are initially at equilibrium. The decompression parameters are engineered such that the final state is identical to that obtained after a perfectly adiabatic transformation despite the fact that the fast decompression is performed in the strongly non-adiabatic regime. During the transfer the atomic sample goes through strongly out-of-equilibrium states while the external confinement is modified until the system reaches the desired stationary state. The scheme is theoretically based on the invariants of motion and scaling equations techniques and can be generalized to decompression trajectories including an arbitrary deformation of the trap. It is also directly applicable to arbitrary initial non-equilibrium sta...

  12. Shortcuts to adiabaticity for trapped ultracold gases

    E-Print Network [OSTI]

    Jean-François Schaff; Pablo Capuzzi; Guillaume Labeyrie; Patrizia Vignolo

    2011-05-11T23:59:59.000Z

    We study, experimentally and theoretically, the controlled transfer of harmonically trapped ultracold gases between different quantum states. In particular we experimentally demonstrate a fast decompression and displacement of both a non-interacting gas and an interacting Bose-Einstein condensate which are initially at equilibrium. The decompression parameters are engineered such that the final state is identical to that obtained after a perfectly adiabatic transformation despite the fact that the fast decompression is performed in the strongly non-adiabatic regime. During the transfer the atomic sample goes through strongly out-of-equilibrium states while the external confinement is modified until the system reaches the desired stationary state. The scheme is theoretically based on the invariants of motion and scaling equations techniques and can be generalized to decompression trajectories including an arbitrary deformation of the trap. It is also directly applicable to arbitrary initial non-equilibrium states.

  13. Magneto-Optical Trapping of Holmium Atoms

    E-Print Network [OSTI]

    J. Miao; J. Hostetter; G. Stratis; M. Saffman

    2014-03-24T23:59:59.000Z

    We demonstrate sub-Doppler laser cooling and magneto-optical trapping of the rare earth element Holmium. Atoms are loaded from an atomic beam source and captured in six-beam $\\sigma_+ - \\sigma_-$ molasses using a strong $J=15/2 \\leftrightarrow J=17/2$ cycling transition at $\\lambda=410.5 \\rm nm$. Due to the small difference in hyperfine splittings and Land\\'e $g$-factors in the lower and upper levels of the cooling transition the MOT is self-repumped without additional repump light, and deep sub-Doppler cooling is achieved with the magnetic trap turned on. We measure the leakage out of the cycling transition to metastable states and find a branching ratio $\\sim 10^{-5}$ which is adequate for state resolved measurements on hyperfine encoded qubits.

  14. Thermodynamics of Interacting Fermions in Atomic Traps

    SciTech Connect (OSTI)

    Chen Qijin; Stajic, Jelena; Levin, K. [James Franck Institute and Department of Physics, University of Chicago, Chicago, Illinois 60637 (United States)

    2005-12-31T23:59:59.000Z

    We calculate the entropy in a trapped, resonantly interacting Fermi gas as a function of temperature for a wide range of magnetic fields between the BCS and Bose-Einstein condensation end points. This provides a basis for the important technique of adiabatic sweep thermometry and serves to characterize quantitatively the evolution and nature of the excitations of the gas. The results are then used to calibrate the temperature in several ground breaking experiments on {sup 6}Li and {sup 40}K.

  15. Ion temperature gradient driven turbulence with strong trapped ion resonance

    SciTech Connect (OSTI)

    Kosuga, Y., E-mail: kosuga@riam.kyushu-u.ac.jp [Institute for Advanced Study, Kyushu University, Fukuoka (Japan); Research Institute for Applied Mechanics, Kyushu University, Fukuoka (Japan); Itoh, S.-I. [Research Center for Plasma Turbulence, Kyushu University, Fukuoka (Japan); Research Institute for Applied Mechanics, Kyushu University, Fukuoka (Japan); Diamond, P. H. [CASS and CMTFO, University of California at San Diego, La Jolla, California 92093 (United States); WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon (Korea, Republic of); Itoh, K. [National Institute for Fusion Science, Gifu (Japan); Research Center for Plasma Turbulence, Kyushu University, Fukuoka (Japan); Lesur, M. [Research Institute for Applied Mechanics, Kyushu University, Fukuoka (Japan)

    2014-10-15T23:59:59.000Z

    A theory to describe basic characterization of ion temperature gradient driven turbulence with strong trapped ion resonance is presented. The role of trapped ion granulations, clusters of trapped ions correlated by precession resonance, is the focus. Microscopically, the presence of trapped ion granulations leads to a sharp (logarithmic) divergence of two point phase space density correlation at small scales. Macroscopically, trapped ion granulations excite potential fluctuations that do not satisfy dispersion relation and so broaden frequency spectrum. The line width from emission due only to trapped ion granulations is calculated. The result shows that the line width depends on ion free energy and electron dissipation, which implies that non-adiabatic electrons are essential to recover non-trivial dynamics of trapped ion granulations. Relevant testable predictions are summarized.

  16. Offline trapping of $^{221}$Fr in a magneto-optical trap from implantation of an $^{225}$Ac ion beam

    E-Print Network [OSTI]

    M. Tandecki; J. Zhang; S. Aubin; J. A. Behr; R. Collister; E. Gomez; G. Gwinner; H. Heggen; J. Lassen; L. A. Orozco; M. R. Pearson; S. Raeder; A. Teigelhöfer

    2014-09-30T23:59:59.000Z

    We demonstrate a new technique to prepare an offline source of francium for trapping in a magneto-optical trap. Implanting a radioactive beam of $^{225}$Ac, $t_{1/2} = 9.920(3)$ days, in a foil, allows use of the decay products, i.e.$^{221}$Fr, $t_{1/2} = 288.0(4)$ s. $^{221}$Fr is ejected from the foil by the $\\alpha$ decay of $^{225}$Ac. This technique is compatible with the online accumulation of a laser-cooled atomic francium sample for a series of planned parity non-conservation measurements at TRIUMF. We obtain a 34% release efficiency for $^{221}$Fr from the recoil source based on particle detector measurements. We find that laser cooling operation with the source is $8^{+10}_{-5}$ times less efficient than from a mass-separated ion beam of $^{221}$Fr in the current geometry. While the flux of this source is two to three orders of magnitude lower than typical francium beams from ISOL facilities, the source provides a longer-term supply of francium for offline studies.

  17. Error Compensation of Single-Qubit Gates in a Surface Electrode Ion Trap Using Composite Pulses

    E-Print Network [OSTI]

    Emily Mount; Chingiz Kabytayev; Stephen Crain; Robin Harper; So-Young Baek; Geert Vrijsen; Steven Flammia; Kenneth R. Brown; Peter Maunz; Jungsang Kim

    2015-04-06T23:59:59.000Z

    The trapped atomic ion qubits feature desirable properties for use in a quantum computer such as long coherence times (Langer et al., 2005), high qubit measurement fidelity (Noek et al., 2013), and universal logic gates (Home et al., 2009). The quality of quantum logic gate operations on trapped ion qubits has been limited by the stability of the control fields at the ion location used to implement the gate operations. For this reason, the logic gates utilizing microwave fields (Brown et al., 2011; Shappert et al., 2013; Harty et al., 2014) have shown gate fidelities several orders of magnitude better than those using laser fields (Knill et al., 2008; Benhelm et al., 2008; Ballance et al., 2014). Here, we demonstrate low-error single-qubit gates performed using stimulated Raman transitions on an ion qubit trapped in a microfabricated chip trap. Gate errors are measured using a randomized benchmarking protocol (Knill et al., 2008; Wallman et al., 2014; Magesan et al., 2012), where amplitude error in the control beam is compensated using various pulse sequence techniques (Wimperis, 1994; Low et al., 2014). Using B2 compensation (Wimperis, 1994), we demonstrate single qubit gates with an average error per randomized Clifford group gate of $3.6(3)\\times10^{-4}$. We also show that compact palindromic pulse compensation sequences (PD$n$) (Low et al., 2014) compensate for amplitude errors as designed.

  18. Subwavelength edge detection through trapped resonances in waveguides

    E-Print Network [OSTI]

    Molerón, Miguel

    2015-01-01T23:59:59.000Z

    Lenses that can collect the perfect image of an object must restore propagative and evanescent waves. However, for efficient information transfer, e.g., in compressed sensing, it is often desirable to detect only the fast spatial variations of the wave field (carried by evanescent waves), as the one created by edges or small details. Image processing edge detection algorithms perform such operation but they add time and complexity to the imaging process. Here, we present a new subwavelength approach that generates an image of only those components of the acoustic field that are equal to or smaller than the operating wavelength. The proposed technique converts evanescent waves into propagative waves exciting trapped resonances in a waveguide, and it uses periodicity to attenuate the propagative components. This approach achieves resolutions about an order of magnitude smaller than the operating wavelength and makes it possible to visualize independently edges aligned along different directions.

  19. Superconducting qubits can be coupled and addressed as trapped ions

    SciTech Connect (OSTI)

    Liu Yuxi; Wei, L. F. [CREST, Japan Science and Technology Agency (JST), Kawaguchi, Saitama 332-0012 (Japan); Frontier Research System, Institute of Physical and Chemical Research (RIKEN), Wako-shi, Saitama 351-0198 (Japan); Johansson, J. R. [Frontier Research System, Institute of Physical and Chemical Research (RIKEN), Wako-shi, Saitama 351-0198 (Japan); Tsai, J. S. [CREST, Japan Science and Technology Agency (JST), Kawaguchi, Saitama 332-0012 (Japan); Frontier Research System, Institute of Physical and Chemical Research (RIKEN), Wako-shi, Saitama 351-0198 (Japan); NEC Fundamental Research Laboratories, Tsukuba, Ibaraki 305-8051 (Japan); Nori, Franco [CREST, Japan Science and Technology Agency (JST), Kawaguchi, Saitama 332-0012 (Japan); Frontier Research System, Institute of Physical and Chemical Research (RIKEN), Wako-shi, Saitama 351-0198 (Japan); Center for Theoretical Physics, Physics Department, Center for the Study of Complex Systems, University of Michigan, Ann Arbor, Michigan 48109-1040 (United States)

    2007-10-01T23:59:59.000Z

    Exploiting the intrinsic nonlinearity of superconducting Josephson junctions, we propose a scalable circuit with superconducting qubits (SCQs) which is very similar to the successful one now being used for trapped ions. The SCQs are coupled to the ''vibrational'' mode provided by a superconducting LC circuit or its equivalent (e.g., a superconducting quantum interference device). Both single-qubit rotations and qubit-LC-circuit couplings and/or decouplings can be controlled by the frequencies of the time-dependent magnetic fluxes. The circuit is scalable since the qubit-qubit interactions, mediated by the LC circuit, can be selectively performed, and the information transfer can be realized in a controllable way.

  20. Trapping and aerogelation of nanoparticles in negative gravity hydrocarbon flames

    SciTech Connect (OSTI)

    Chakrabarty, Rajan K., E-mail: rajan.chakrabarty@gmail.com [Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130 (United States); Laboratory for Aerosol Science, Spectroscopy, and Optics, Desert Research Institute, Nevada System of Higher Education, Reno, Nevada 89512 (United States); Novosselov, Igor V. [Department of Mechanical Engineering, University of Washington, Seattle, Washington 98195 (United States); Enertechnix Inc., Maple Valley, Washington 98068 (United States); Beres, Nicholas D.; Moosmüller, Hans [Laboratory for Aerosol Science, Spectroscopy, and Optics, Desert Research Institute, Nevada System of Higher Education, Reno, Nevada 89512 (United States); Sorensen, Christopher M. [Condensed Matter Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506 (United States); Stipe, Christopher B. [TSI Incorporated, 500 Cardigan Rd, Shoreview, Minnesota 55126 (United States)

    2014-06-16T23:59:59.000Z

    We report the experimental realization of continuous carbon aerogel production using a flame aerosol reactor by operating it in negative gravity (?g; up-side-down configuration). Buoyancy opposes the fuel and air flow forces in ?g, which eliminates convectional outflow of nanoparticles from the flame and traps them in a distinctive non-tipping, flicker-free, cylindrical flame body, where they grow to millimeter-size aerogel particles and gravitationally fall out. Computational fluid dynamics simulations show that a closed-loop recirculation zone is set up in ?g flames, which reduces the time to gel for nanoparticles by ?10{sup 6}?s, compared to positive gravity (upward rising) flames. Our results open up new possibilities of one-step gas-phase synthesis of a wide variety of aerogels on an industrial scale.

  1. An optically trapped mirror for reaching the standard quantum limit

    E-Print Network [OSTI]

    Nobuyuki Matsumoto; Yuta Michimura; Yoichi Aso; Kimio Tsubono

    2014-05-19T23:59:59.000Z

    The preparation of a mechanical oscillator driven by quantum back-action is a fundamental requirement to reach the standard quantum limit (SQL) for force measurement, in optomechanical systems. However, thermal fluctuating force generally dominates a disturbance on the oscillator. In the macroscopic scale, an optical linear cavity including a suspended mirror has been used for the weak force measurement, such as gravitational-wave detectors. This configuration has the advantages of reducing the dissipation of the pendulum (i.e., suspension thermal noise) due to a gravitational dilution by using a thin wire, and of increasing the circulating laser power. However, the use of the thin wire is weak for an optical torsional anti-spring effect in the cavity, due to the low mechanical restoring force of the wire. Thus, there is the trade-off between the stability of the system and the sensitivity. Here, we describe using a triangular optical cavity to overcome this limitation for reaching the SQL. The triangular cavity can provide a sensitive and stable system, because it can optically trap the mirror's motion of the yaw, through an optical positive torsional spring effect. To show this, we demonstrate a measurement of the torsional spring effect caused by radiation pressure forces.

  2. Characterization of Trapped Lignin-Degrading Microbes in Tropical Forest Soil

    SciTech Connect (OSTI)

    DeAngelis, Kristen; Allgaier, Martin; Chavarria, Yaucin; Fortney, Julian; Hugenholtz, Phillip; Simmons, Blake; Sublette, Kerry; Silver, Whendee; Hazen, Terry

    2011-07-14T23:59:59.000Z

    Lignin is often the most difficult portion of plant biomass to degrade, with fungi generally thought to dominate during late stage decomposition. Lignin in feedstock plant material represents a barrier to more efficient plant biomass conversion and can also hinder enzymatic access to cellulose, which is critical for biofuels production. Tropical rain forest soils in Puerto Rico are characterized by frequent anoxic conditions and fluctuating redox, suggesting the presence of lignin-degrading organisms and mechanisms that are different from known fungal decomposers and oxygen-dependent enzyme activities. We explored microbial lignin-degraders by burying bio-traps containing lignin-amended and unamended biosep beads in the soil for 1, 4, 13 and 30 weeks. At each time point, phenol oxidase and peroxidase enzyme activity was found to be elevated in the lignin-amended versus the unamended beads, while cellulolytic enzyme activities were significantly depressed in lignin-amended beads. Quantitative PCR of bacterial communities showed more bacterial colonization in the lignin-amended compared to the unamended beads after one and four weeks, suggesting that the lignin supported increased bacterial abundance. The microbial community was analyzed by small subunit 16S ribosomal RNA genes using microarray (PhyloChip) and by high-throughput amplicon pyrosequencing based on universal primers targeting bacterial, archaeal, and eukaryotic communities. Community trends were significantly affected by time and the presence of lignin on the beads. Lignin-amended beads have higher relative abundances of representatives from the phyla Actinobacteria, Firmicutes, Acidobacteria and Proteobacteria compared to unamended beads. This study suggests that in low and fluctuating redox soils, bacteria could play a role in anaerobic lignin decomposition.

  3. Characterization of trapped lignin-degrading microbes in tropical forest soil

    SciTech Connect (OSTI)

    DeAngelis, K.M.; Allgaier, M.; Chavarria, Y.; Fortney, J.L.; Hugenholz, P.; Simmons, B.; Sublette, K.; Silver, W.L.; Hazen, T.C.

    2011-03-01T23:59:59.000Z

    Lignin is often the most difficult portion of plant biomass to degrade, with fungi generally thought to dominate during late stage decomposition. Lignin in feedstock plant material represents a barrier to more efficient plant biomass conversion and can also hinder enzymatic access to cellulose, which is critical for biofuels production. Tropical rain forest soils in Puerto Rico are characterized by frequent anoxic conditions and fluctuating redox, suggesting the presence of lignin-degrading organisms and mechanisms that are different from known fungal decomposers and oxygen-dependent enzyme activities. We explored microbial lignin-degraders by burying bio-traps containing lignin-amended and unamended biosep beads in the soil for 1, 4, 13 and 30 weeks. At each time point, phenol oxidase and peroxidase enzyme activity was found to be elevated in the lignin-amended versus the unamended beads, while cellulolytic enzyme activities were significantly depressed in lignin-amended beads. Quantitative PCR of bacterial communities showed more bacterial colonization in the lignin-amended compared to the unamended beads after one and four weeks, suggesting that the lignin supported increased bacterial abundance. The microbial community was analyzed by small subunit 16S ribosomal RNA genes using microarray (PhyloChip) and by high-throughput amplicon pyrosequencing based on universal primers targeting bacterial, archaeal, and eukaryotic communities. Community trends were significantly affected by time and the presence of lignin on the beads. Lignin-amended beads have higher relative abundances of representatives from the phyla Actinobacteria, Firmicutes, Acidobacteria and Proteobacteria compared to unamended beads. This study suggests that in low and fluctuating redox soils, bacteria could play a role in anaerobic lignin decomposition.

  4. Characterization of Trapped Lignin-Degrading Microbes in Tropical Forest Soil

    SciTech Connect (OSTI)

    DeAngelis, Kristen M.; Allgaier, Martin; Chavarria, Yaucin; Fortney, Julian L.; Hugenholtz, Philip; Simmons, Blake A.; Sublette, Kerry; Silver, Whendee; Hazen, Terry C.

    2011-04-29T23:59:59.000Z

    Lignin is often the most difficult portion of plant biomass to degrade, with fungi generally thought to dominate during late stage decomposition. Lignin in feedstock plant material represents a barrier to more efficient plant biomass conversion and can also hinder enzymatic access to cellulose, which is critical for biofuels production. Tropical rain forest soils in Puerto Rico are characterized by frequent anoxic conditions and fluctuating redox, suggesting the presence of lignin-degrading organisms and mechanisms that are different from known fungal decomposers and oxygen-dependent enzyme activities. We explored microbial lignin-degraders by burying bio-traps containing lignin-amended and unamended biosep beads in the soil for 1, 4, 13 and 30 weeks. At each time point, phenol oxidase and peroxidase enzyme activity was found to be elevated in the lignin-amended versus the unamended beads, while cellulolytic enzyme activities were significantly depressed in lignin-amended beads. Quantitative PCR of bacterial communities showed more bacterial colonization in the lignin-amended compared to the unamended beads after one and four weeks, suggesting that the lignin supported increased bacterial abundance. The microbial community was analyzed by small subunit 16S ribosomal RNA genes using microarray (PhyloChip) and by high-throughput amplicon pyrosequencing based on universal primers targeting bacterial, archaeal, and eukaryotic communities. Community trends were significantly affected by time and the presence of lignin on the beads. Lignin-amended beads have higher relative abundances of representatives from the phyla Actinobacteria, Firmicutes, Acidobacteria and Proteobacteria compared to unamended beads. This study suggests that in low and fluctuating redox soils, bacteria could play a role in anaerobic lignin decomposition.

  5. Isotopic abundance in atom trap trace analysis

    DOE Patents [OSTI]

    Lu, Zheng-Tian; Hu, Shiu-Ming; Jiang, Wei; Mueller, Peter

    2014-03-18T23:59:59.000Z

    A method and system for detecting ratios and amounts of isotopes of noble gases. The method and system is constructed to be able to measure noble gas isotopes in water and ice, which helps reveal the geological age of the samples and understand their movements. The method and system uses a combination of a cooled discharge source, a beam collimator, a beam slower and magneto-optic trap with a laser to apply resonance frequency energy to the noble gas to be quenched and detected.

  6. Gas turbine engines with particle traps

    DOE Patents [OSTI]

    Boyd, Gary L. (Tempe, AZ); Sumner, D. Warren (Phoenix, AZ); Sheoran, Yogendra (Scottsdale, AZ); Judd, Z. Daniel (Phoenix, AZ)

    1992-01-01T23:59:59.000Z

    A gas turbine engine (10) incorporates a particle trap (46) that forms an entrapment region (73) in a plenum (24) which extends from within the combustor (18) to the inlet (32) of a radial-inflow turbine (52, 54). The engine (10) is thereby adapted to entrap particles that originate downstream from the compressor (14) and are otherwise propelled by combustion gas (22) into the turbine (52, 54). Carbonaceous particles that are dislodged from the inner wall (50) of the combustor (18) are incinerated within the entrapment region (73) during operation of the engine (10).

  7. HiTrap Affinity columns HiTrap Wheat Germ Lectin, 1 ml INSTRUCTIONS

    E-Print Network [OSTI]

    Lebendiker, Mario

    be operated with a syringe, peristaltic pump or a chromatography system. Buffer preparation Water. The column can be operated with a syringe, peristaltic pump or liquid chromatography system such as Ã?KTATM for HiTrap Wheat Germ Lectin include separation and purification of glycoproteins and polysaccharides

  8. Energy Efficient Steam Trapping of Trace Heating Systems

    E-Print Network [OSTI]

    Krueger, R. G.; Wilt, G. W.

    1981-01-01T23:59:59.000Z

    orifices. However, each orifice is limited to an operating range of 15-25 PSI pressure variations since an inlet pressure higher than the range for a given orifice size will cause the trap to remain closed. This will cause heavy wear on linkages... rate of 100 lbs/hr gave the best balance between trap sizing and tracer length. For anything less than that, the trap would be very inefficient. The reason for this approach was based on the fact that orifice sizes available in all traps were very...

  9. Ratchet Cellular Automata for Colloids in Dynamic Traps

    E-Print Network [OSTI]

    C. J. Olson Reichhardt; C. Reichhardt

    2006-02-13T23:59:59.000Z

    We numerically investigate the transport of kinks in a ratchet cellular automata geometry for colloids interacting with dynamical traps. We find that thermal effects can enhance the transport efficiency in agreement with recent experiments. At high temperatures we observe the creation and annihilation of thermally induced kinks that degrade the signal transmission. We consider both the deterministic and stochastic cases and show how the trap geometry can be adjusted to switch between these two cases. The operation of the dynamical trap geometry can be achieved with the adjustment of fewer parameters than ratchet cellular automata constructed using static traps.

  10. adult trapping program: Topics by E-print Network

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

    Annual Industrial...EVALUATING STEAM TRAP PERFORMANCE Noel Y Fuller, P.E. Holston Defense Corporation Kingsport, Tennessee ABSTRACT Laboratory tests were conducted on several types...

  11. acid phosphatase trap: Topics by E-print Network

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

    Annual Industrial...EVALUATING STEAM TRAP PERFORMANCE Noel Y Fuller, P.E. Holston Defense Corporation Kingsport, Tennessee ABSTRACT Laboratory tests were conducted on several types...

  12. Requirements-Driven Diesel Catalyzed Particulate Trap Design...

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

    Requirements Driven Diesel Catalyzed Particulate Trap (DCPT) Design and Optimization Tom Harris, Donna McConnell and Danan Dou Delphi Catalyst Tulsa, Oklahoma 2 Euro 45 Light Duty...

  13. Location Of Hole And Electron Traps On Nanocrystalline Anatase...

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

    to two overlapping distributions: hole trap emission associated with oxygen vacancies on (101) exposed surfaces, which peaks in the green, and a broader emission...

  14. A Microscale Gas Trapping Investigation Markus Buchgraber, Anthony R. Kovscek

    E-Print Network [OSTI]

    Stanford University

    A Microscale Gas Trapping Investigation Markus Buchgraber, Anthony R. Kovscek Department of Energy=water saturation In-outlet ports Parameters Experimental Work Setup Experimental Results The purpose

  15. H2-Assisted NOx Traps: Test Cell Results Vehicle Installations

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

    * New Power Supply * Under 250W consumption * Minimal heat rejected * Compact transformer * High-temperature flange seals * Reduced leakage 4 H2-Assisted NOx Trap: Test...

  16. Characterisation of Dust Particles Trapped in Silica Aerogels.

    E-Print Network [OSTI]

    Liu, Bing

    2011-01-01T23:59:59.000Z

    ?? This thesis involves the study of dust particles trapped in silica aerogel for fusion dust diagnostics purpose. The low velocity impact experiments are done… (more)

  17. Storage of Ultracold Neutrons in the Magneto-Gravitational Trap of the UCN Experiment

    SciTech Connect (OSTI)

    Salvat, D. J. [Indiana University] [Indiana University; Adamek, E. R. [Indiana University] [Indiana University; Barlow, D. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Bowman, James D [ORNL] [ORNL; Broussard, L. J. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Callahan, N. B. [Indiana University] [Indiana University; Clayton, S. M. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Cude-Woods, C. [Indiana University] [Indiana University; Currie, S. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Dees, E. B. [North Carolina State University, Raleigh] [North Carolina State University, Raleigh; Fox, W. [Indiana University] [Indiana University; Geltenbort, P. [Inst Max Von Laue Paul Langevin, Grenoble, France] [Inst Max Von Laue Paul Langevin, Grenoble, France; Hickerson, K. P. [University of California, Los Angeles] [University of California, Los Angeles; Holley, A. T. [Indiana University] [Indiana University; Liu, C.-Y. [Indiana University] [Indiana University; Makela, M. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Medina, J. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Morley, D. J. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Morris, C. L. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Penttila, Seppo I [ORNL] [ORNL; Ramsey, J. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Saunders, A. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Seestrom, S. J. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Sharapov, E. I. [Joint Institute for Nuclear Research, Dubna, Russia] [Joint Institute for Nuclear Research, Dubna, Russia; Sjue, S. K. L. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Slaughter, B. A. [Indiana University] [Indiana University; Vanderwerp, J. [Indiana University] [Indiana University; VornDick, B. [North Carolina State University, Raleigh] [North Carolina State University, Raleigh; Walstrom, P. L. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Wang, Z. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Womack, T. L. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Young, A. R. [North Carolina State University, Raleigh] [North Carolina State University, Raleigh

    2014-01-01T23:59:59.000Z

    The UCN experiment is designed to measure the lifetime n of the free neutron by trapping ultracold neutrons (UCN) in a magneto-gravitational trap. An asymmetric bowl-shaped NdFeB magnet Halbach array confines low-field-seeking UCN within the apparatus, and a set of electromagnetic coils in a toroidal geometry provides a background holding field to eliminate depolarization-induced UCN loss caused by magnetic field nodes. We present a measurement of the storage time store of the trap by storing UCN for various times and counting the survivors. The data are consistent with a single exponential decay, and we find store = 860 19 s, within 1 of current global averages for n. The storage time with the holding field deactivated is found to be store = 470 160 s; this decreased storage time is due to the loss of UCN, which undergo Majorana spin flips while being stored. We discuss plans to increase the statistical sensitivity of the measurement and investigate potential systematic effects.

  18. Parallel heat flux and flow acceleration in open field line plasmas with magnetic trapping

    SciTech Connect (OSTI)

    Guo, Zehua; Tang, Xian-Zhu; McDevitt, Chris [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2014-10-15T23:59:59.000Z

    The magnetic field strength modulation in a tokamak scrape-off layer (SOL) provides both flux expansion next to the divertor plates and magnetic trapping in a large portion of the SOL. Previously, we have focused on a flux expander with long mean-free-path, motivated by the high temperature and low density edge anticipated for an absorbing boundary enabled by liquid lithium surfaces. Here, the effects of magnetic trapping and a marginal collisionality on parallel heat flux and parallel flow acceleration are examined. The various transport mechanisms are captured by kinetic simulations in a simple but representative mirror-expander geometry. The observed parallel flow acceleration is interpreted and elucidated with a modified Chew-Goldberger-Low model that retains temperature anisotropy and finite collisionality.

  19. Thermodynamics analogue for self-trapped spinning-stationary Madelung fluid

    E-Print Network [OSTI]

    Agung Budiyono

    2010-06-25T23:59:59.000Z

    We discuss two-dimensional Madelung fluid dynamics whose irrotational case reduces into the Schr\\"odinger equation for a free single particle. We show that the self-trapped spinning-stationary Madelung fluid reported in the previous paper can be analogically identified as an equilibrium thermodynamics system. This is done by making correspondence between Shannon entropy over Madelung density and internal energy to be defined in the main text, respectively with thermal-entropy and thermal-internal energy of equilibrium thermodynamics system. This leads us to identify a Madelung fluid analog of thermal-temperature at the vanishing value of which the stationary Madelung fluid will be no more spinning and is equal to the quantum mechanical ground state of a particle trapped inside a cylindrical tube external potential.

  20. ECOLOGY AND BEHAVIOR Treating Panel Traps With a Fluoropolymer Enhances Their Efficiency

    E-Print Network [OSTI]

    Hanks, Lawrence M.

    ECOLOGY AND BEHAVIOR Treating Panel Traps With a Fluoropolymer Enhances Their Efficiency to improve trap capture and retention, researchers have treated intercept traps with Rain-X, a polysiloxane that are deployed to capture cerambycid beetles, using untreated traps as controls. Fluon-treated traps captured

  1. An Energy Signature Scheme for Steam Trap Assessment and Flow Rate Estimation Using Pipe-Induced Acoustic Measurements

    SciTech Connect (OSTI)

    Olama, Mohammed M [ORNL; Allgood, Glenn O [ORNL; Kuruganti, Phani Teja [ORNL; Lake, Joe E [ORNL

    2012-01-01T23:59:59.000Z

    The US Congress has passed legislation dictating that all government agencies establish a plan and process for improving energy efficiencies at their sites. In response to this legislation, Oak Ridge National Laboratory (ORNL) has recently conducted a pilot study to explore the deployment of a wireless sensor system for a real-time measurement-based energy efficiency optimization framework within the steam distribution system within the ORNL campus. We make assessments on the real-time status of the distribution system by observing the state measurements of acoustic sensors mounted on the steam pipes/traps/valves. In this paper, we describe a spectral-based energy signature scheme that interprets acoustic vibration sensor data to estimate steam flow rates and assess steam traps health status. Experimental results show that the energy signature scheme has the potential to identify different steam trap health status and it has sufficient sensitivity to estimate steam flow rate. Moreover, results indicate a nearly quadratic relationship over the test region between the overall energy signature factor and flow rate in the pipe. The analysis based on estimated steam flow and steam trap status helps generate alerts that enable operators and maintenance personnel to take remedial action. The goal is to achieve significant energy-saving in steam lines by monitoring and acting on leaking steam pipes/traps/valves.

  2. Optimal control of entangling operations for trapped-ion quantum computing V. Nebendahl,1

    E-Print Network [OSTI]

    Blatt, Rainer

    . In the quantum circuit model, information is encoded in quantum bits qu- bits and manipulated by applying unitary to a vibrational mode of the ions' motion in the trap. To achieve a gate on either a specific ion or a pair of ions that it interacts only with a single ion at a time 6 . Then, a CNOT gate or an equivalent entangling gate between

  3. Successful Implementation of a Sustainable Trap Management Program.

    E-Print Network [OSTI]

    Walter, J.

    2013-01-01T23:59:59.000Z

    significant cost penalty in delaying implementation of a program to manage the steam trap population. Plants typically embark on a trap management initiative by focusing on a survey, but may not maximize returns because they fail to execute or sustain possible...

  4. Steam Traps-The Oft Forgotten Energy Conservation Treasure

    E-Print Network [OSTI]

    Pychewicz, F. S.

    In these days of high technology, the steam trap is often treated as a commodity item, forgotten by many and respected by a relative few. Yet, in many facilities, widespread undetected failure of steam traps has wasted 5-15% of a plant's total steam...

  5. Novel Dipole Trapped Spheromak Configuration M. R. Brown,1,

    E-Print Network [OSTI]

    Brown, Michael R.

    Novel Dipole Trapped Spheromak Configuration M. R. Brown,1, * C. D. Cothran,1 J. Fung,1 M. J. Schaffer,2 and E. Belova3 We report the observation and characterization of a spheromak formed in the Swarthmore Spheromak Experiment (SSX) and trapped in a simple dipole magnetic field. The spheromak is studied

  6. Solar cell efficiency enhancement via light trapping in printable resonant

    E-Print Network [OSTI]

    Atwater, Harry

    Solar cell efficiency enhancement via light trapping in printable resonant dielectric nanosphere for addressing the key challenge of light trapping in thin-film solar cells. We experimentally and theoretically the absorber, junction, and passivation layers. Recently, a number of innovative solar cell light

  7. Dielectric nanostructures for broadband light trapping in organic solar cells

    E-Print Network [OSTI]

    Fan, Shanhui

    Dielectric nanostructures for broadband light trapping in organic solar cells Aaswath Raman, Zongfu light trapping configuration for thin-film solar cells," Appl. Phys. Lett. 91, 243501 (2007). 8. M@stanford.edu Abstract: Organic bulk heterojunction solar cells are a promising candidate for low-cost next

  8. Solar cell efficiency enhancement via light trapping in printable resonant

    E-Print Network [OSTI]

    Grandidier, Jonathan

    Solar cell efficiency enhancement via light trapping in printable resonant dielectric nanosphere for addressing the key challenge of light trapping in thin-film solar cells. We experimentally and theoretically, photovoltaics, resonant dielectric structures, solar cells * Corresponding author: e-mail jgrandid

  9. Broadband laser cooling of trapped atoms with ultrafast pulses

    E-Print Network [OSTI]

    Blinov, Boris

    Broadband laser cooling of trapped atoms with ultrafast pulses B. B. Blinov,* R. N. Kohn, Jr., M. J ions in an rf trap using ultrafast pulses from a mode-locked laser. The temperature of a single ion On the other hand, an ultrafast laser whose pulse is a few picoseconds long will naturally have a bandwidth

  10. Blue Crab, Callinectes sapidus, Trap Selectivity Studies: Mesh Size

    E-Print Network [OSTI]

    Blue Crab, Callinectes sapidus, Trap Selectivity Studies: Mesh Size VINCENT GUILLORY and PAUL had replaced drop nets and trot lines as the dominant gear in the commercial blue crab, Callinectes, LA 70343. ABSTRACT-Catch rates and sizes of blue crabs, Callinectes sapidus, were com pared in traps

  11. Biodiversity Conservation and Poverty Traps December 2, 2009

    E-Print Network [OSTI]

    Angenent, Lars T.

    Biodiversity Conservation and Poverty Traps December 2, 2009 Co-organizers Alex Travis and Chris biodiversity conservation and poverty traps. Multiple participants observed that Cornell has relatively large. A good deal of discussion concerned the emphasis on biodiversity conservation as opposed to broader

  12. Particle-optical self-trapping

    SciTech Connect (OSTI)

    Gordon, R.; Blakely, J. T.; Sinton, D. [Department of Electrical and Computer Engineering, University of Victoria, Victoria, British Columbia, Canada V8P 5C2 (Canada); Department of Mechanical Engineering, University of Victoria, Victoria, British Columbia, Canada V8W 2Y2 (Canada)

    2007-05-15T23:59:59.000Z

    The formation of a self-guided beam pattern via optical trapping in a suspension of Rayleigh scatterers is studied. An analytic self-guided solution is presented that is valid for low intensities. A numerical solution of the coupled diffusion and optical-wave equations is presented, which shows an evolution toward a steady state that is independent of the initial optical beam shape. At higher intensities, the numerical solution shows the influence of higher-order nonlinearities, which lead to instability. We define a critical optical intensity, in terms of the particle size, refractive index contrast, and thermal energy, that characterizes the onset of higher-order effects. Instability is found that is consistent with past parametric studies of solitons.

  13. Switchable cell trapping using superparamagnetic beads

    SciTech Connect (OSTI)

    Bryan, M. T.; Smith, K. H.; Real, M. E.; Bashir, M. A.; Fry, P. W.; Fischer, P.; Im, M.-Y.; Schrefl, T.; Allwood, D. A.; Haycock, J. W.

    2010-04-30T23:59:59.000Z

    Ni{sub 81}Fe{sub 19} microwires are investigated as the basis of a switchable template for positioning magnetically-labeled neural Schwann cells. Magnetic transmission X-ray microscopy and micromagnetic modeling show that magnetic domain walls can be created or removed in zigzagged structures by an applied magnetic field. Schwann cells containing superparamagnetic beads are trapped by the field emanating from the domain walls. The design allows Schwann cells to be organized on a surface to form a connected network and then released from the surface if required. As aligned Schwann cells can guide nerve regeneration, this technique is of value for developing glial-neuronal co-culture models in the future treatment of peripheral nerve injuries.

  14. Contaminant trap for gas-insulated apparatus

    DOE Patents [OSTI]

    Adcock, James L. (Knoxville, TN); Pace, Marshall O. (Knoxville, TN); Christophorou, Loucas G. (Oak Ridge, TN)

    1984-01-01T23:59:59.000Z

    A contaminant trap for a gas-insulated electrical conductor is provided. A resinous dielectric body such as Kel-F wax, grease or other sticky polymeric or oligomeric compound is disposed on the inside wall of the outer housing for the conductor. The resinous body is sufficiently sticky at ambient temperatures to immobilize contaminant particles in the insulating gas on the exposed surfaces thereof. An electric resistance heating element is disposed in the resinous body to selectively raise the temperature of the resinous body to a molten state so that the contaminant particles collected on the surface of the body sink into the body so that the surface of the resinous body is renewed to a particle-less condition and, when cooled, returns to a sticky collecting surface.

  15. Debris trap in a turbine cooling system

    DOE Patents [OSTI]

    Wilson, Ian David (Clifton Park, NY)

    2002-01-01T23:59:59.000Z

    In a turbine having a rotor and a plurality of stages, each stage comprising a row of buckets mounted on the rotor for rotation therewith; and wherein the buckets of at least one of the stages are cooled by steam, the improvement comprising at least one axially extending cooling steam supply conduit communicating with an at least partially annular steam supply manifold; one or more axially extending cooling steam feed tubes connected to the manifold at a location radially outwardly of the cooling steam supply conduit, the feed tubes arranged to supply cooling steam to the buckets of at least one of the plurality of stages; the manifold extending radially beyond the feed tubes to thereby create a debris trap region for collecting debris under centrifugal loading caused by rotation of the rotor.

  16. Electrostatic particle trap for ion beam sputter deposition

    DOE Patents [OSTI]

    Vernon, Stephen P. (Pleasanton, CA); Burkhart, Scott C. (Livermore, CA)

    2002-01-01T23:59:59.000Z

    A method and apparatus for the interception and trapping of or reflection of charged particulate matter generated in ion beam sputter deposition. The apparatus involves an electrostatic particle trap which generates electrostatic fields in the vicinity of the substrate on which target material is being deposited. The electrostatic particle trap consists of an array of electrode surfaces, each maintained at an electrostatic potential, and with their surfaces parallel or perpendicular to the surface of the substrate. The method involves interception and trapping of or reflection of charged particles achieved by generating electrostatic fields in the vicinity of the substrate, and configuring the fields to force the charged particulate material away from the substrate. The electrostatic charged particle trap enables prevention of charged particles from being deposited on the substrate thereby enabling the deposition of extremely low defect density films, such as required for reflective masks of an extreme ultraviolet lithography (EUVL) system.

  17. A Pneumatic Actuated Microfluidic Beads-Trapping Device

    SciTech Connect (OSTI)

    Shao, Guocheng; Cai, Ziliang; Wang, Jun; Wang, Wanjun; Lin, Yuehe

    2011-08-20T23:59:59.000Z

    The development of a polydimethylsiloxane (PDMS) microfluidic microbeads trapping device is reported in this paper. Besides fluid channels, the proposed device includes a pneumatic control chamber and a beads-trapping chamber with a filter array structure. The pneumatic flow control chamber and the beads-trapping chamber are vertically stacked and separated by a thin membrane. By adjusting the pressure in the pneumatic control chamber, the membrane can either be pushed against the filter array to set the device in trapping mode or be released to set the device in releasing mode. In this paper, a computational fluid dynamics simulation was conducted to optimize the geometry design of the filter array structure; the device fabrication was also carried out. The prototype device was tested and the preliminary experimental results showed that it can be used as a beads-trapping unit for various biochemistry and analytical chemistry applications, especially for flow injection analysis systems.

  18. AMEAerospace & Mechanical

    E-Print Network [OSTI]

    Wang, Hai

    AMEAerospace & Mechanical Engineering #12;Aerospace and Mechanical Engineers design complex mechanical, thermal, fluidic, acousti- cal, optical, and electronic systems, with char- acteristic sizes space. Aerospace and Mechanical Engineering (AME) students conduct basic and applied research within

  19. Measurements of electric field noise and light-induced charging in cryogenic surface electrode ion traps

    E-Print Network [OSTI]

    Lachenmyer, Nathan S. (Nathan Scott)

    2010-01-01T23:59:59.000Z

    Ion traps provide an excellent tool for controlling and observing the state of a single trapped ion. For this reason, ion traps have been proposed as a possible system for large-scale quantum computation. However, many ...

  20. Demonstration of a Scalable, Multiplexed Ion Trap for Quantum Information Processing

    E-Print Network [OSTI]

    Leibrandt, David R.

    A scalable, multiplexed ion trap for quantum information processing is fabricated and tested. The trap design and fabrication process are optimized for scalability to small trap size and large numbers of interconnected ...

  1. Laser Cooling of Trapped Ions. W. M. ITANO,J. C. BERGQUIST,J. J. BOLLINGERand D. J. WINELAND

    E-Print Network [OSTI]

    techniques, because the ions can be held for long peri- ods in a well-controlled environment. CoolingLaser Cooling of Trapped Ions. W. M. ITANO,J. C. BERGQUIST,J. J. BOLLINGERand D. J. WINELAND Time ordered structures of ions, can be observed only at low temperatures. We use the term cooling*to mean

  2. Properties of Trapped Electron Bunches in a Plasma Wakefield Accelerator

    SciTech Connect (OSTI)

    Kirby, Neil; /SLAC

    2009-10-30T23:59:59.000Z

    Plasma-based accelerators use the propagation of a drive bunch through plasma to create large electric fields. Recent plasma wakefield accelerator (PWFA) experiments, carried out at the Stanford Linear Accelerator Center (SLAC), successfully doubled the energy for some of the 42 GeV drive bunch electrons in less than a meter; this feat would have required 3 km in the SLAC linac. This dissertation covers one phenomenon associated with the PWFA, electron trapping. Recently it was shown that PWFAs, operated in the nonlinear bubble regime, can trap electrons that are released by ionization inside the plasma wake and accelerate them to high energies. These trapped electrons occupy and can degrade the accelerating portion of the plasma wake, so it is important to understand their origins and how to remove them. Here, the onset of electron trapping is connected to the drive bunch properties. Additionally, the trapped electron bunches are observed with normalized transverse emittance divided by peak current, {epsilon}{sub N,x}/I{sub t}, below the level of 0.2 {micro}m/kA. A theoretical model of the trapped electron emittance, developed here, indicates that the emittance scales inversely with the square root of the plasma density in the non-linear 'bubble' regime of the PWFA. This model and simulations indicate that the observed values of {epsilon}{sub N,x}/I{sub t} result from multi-GeV trapped electron bunches with emittances of a few {micro}m and multi-kA peak currents. These properties make the trapped electrons a possible particle source for next generation light sources. This dissertation is organized as follows. The first chapter is an overview of the PWFA, which includes a review of the accelerating and focusing fields and a survey of the remaining issues for a plasma-based particle collider. Then, the second chapter examines the physics of electron trapping in the PWFA. The third chapter uses theory and simulations to analyze the properties of the trapped electron bunches. Chapters four and five present the experimental diagnostics and measurements for the trapped electrons. Next, the sixth chapter introduces suggestions for future trapped electron experiments. Then, Chapter seven contains the conclusions. In addition, there is an appendix chapter that covers a topic which is extraneous to electron trapping, but relevant to the PWFA. This chapter explores the feasibility of one idea for the production of a hollow channel plasma, which if produced could solve some of the remaining issues for a plasma-based collider.

  3. Phase-Space Volume of Regions of Trapped Motion: Multiple Ring Components and Arcs

    E-Print Network [OSTI]

    L. Benet; O. Merlo

    2008-10-30T23:59:59.000Z

    The phase--space volume of regions of regular or trapped motion, for bounded or scattering systems with two degrees of freedom respectively, displays universal properties. In particular, sudden reductions in the phase-space volume or gaps are observed at specific values of the parameter which tunes the dynamics; these locations are approximated by the stability resonances. The latter are defined by a resonant condition on the stability exponents of a central linearly stable periodic orbit. We show that, for more than two degrees of freedom, these resonances can be excited opening up gaps, which effectively separate and reduce the regions of trapped motion in phase space. Using the scattering approach to narrow rings and a billiard system as example, we demonstrate that this mechanism yields rings with two or more components. Arcs are also obtained, specifically when an additional (mean-motion) resonance condition is met. We obtain a complete representation of the phase-space volume occupied by the regions of trapped motion.

  4. Progress towards high precision measurements on ultracold metastable hydrogen and trapping deuterium

    E-Print Network [OSTI]

    Steinberger, Julia K., 1974-

    2004-01-01T23:59:59.000Z

    (cont.) not achieve deuterium trapping through helium-surface cooling. It is proposed that buffer gas loading can be used to cryogenically cool and trap deuterium.

  5. Quantum Mechanics and Gravitation

    E-Print Network [OSTI]

    A. Westphal

    2003-04-08T23:59:59.000Z

    In summer 1999 an experiment at ILL, Grenoble was conducted. So-called ultra-cold neutrons (UCN) were trapped in the vertical direction between the Fermi-potential of a smooth mirror below and the gravitational potential of the earth above [Ne00, Ru00]. If quantum mechanics turns out to be a sufficiently correct description of the phenomena in the regime of classical, weak gravitation, one should observe the forming of quantized bound states in the vertical direction above a mirror. Already in a simplified view, the data of the experiment provides strong evidence for the existence of such gravitationally bound quantized states. A successful quantum-mechanical description would then provide a convincing argument, that the socalled first quantization can be used for gravitation as an interaction potential, as this is widely expected. Furthermore, looking at the characteristic length scales of about 10 mikron of such bound states formed by UCN, one sees, that a complete quantum mechanical description of this experiment additionally would enable one to check for possible modifications of Newtonian gravitation on distance scales being one order of magnitude below currently available tests [Ad00]. The work presented here deals mainly with the development of a quantum mechanical description of the experiment.

  6. First Use of High Charge States for Mass Measurements of Short-lived Nuclides in a Penning Trap

    E-Print Network [OSTI]

    S. Ettenauer; M. C. Simon; A. T. Gallant; T. Brunner; U. Chowdhury; V. V. Simon; M. Brodeur; A. Chaudhuri; E. Mané; C. Andreoiu; G. Audi; J. R. Crespo López-Urrutia; P. Delheij; G. Gwinner; A. Lapierre; D. Lunney; M. R. Pearson; R. Ringle; J. Ullrich; J. Dilling

    2011-09-15T23:59:59.000Z

    Penning trap mass measurements of short-lived nuclides have been performed for the first time with highly-charged ions (HCI), using the TITAN facility at TRIUMF. Compared to singly-charged ions, this provides an improvement in experimental precision that scales with the charge state q. Neutron-deficient Rb-isotopes have been charge bred in an electron beam ion trap to q = 8 - 12+ prior to injection into the Penning trap. In combination with the Ramsey excitation scheme, this unique setup creating low energy, highly-charged ions at a radioactive beam facility opens the door to unrivalled precision with gains of 1-2 orders of magnitude. The method is particularly suited for short-lived nuclides such as the superallowed {\\beta} emitter 74Rb (T1/2 = 65 ms). The determination of its atomic mass and an improved QEC-value are presented.

  7. Charge-trapping characteristics of fluorinated thin ZrO{sub 2} film for nonvolatile memory applications

    SciTech Connect (OSTI)

    Huang, X. D., E-mail: eexdhuang@gmail.com, E-mail: laip@eee.hku.hk [Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing 210096 (China); Shi, R. P.; Lai, P. T., E-mail: eexdhuang@gmail.com, E-mail: laip@eee.hku.hk [Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (China)

    2014-04-21T23:59:59.000Z

    The effects of fluorine treatment on the charge-trapping characteristics of thin ZrO{sub 2} film are investigated by physical and electrical characterization techniques. The formation of silicate interlayer at the ZrO{sub 2}/SiO{sub 2} interface is effectively suppressed by fluorine passivation. However, excessive fluorine diffusion into the Si substrate deteriorates the quality of the SiO{sub 2}/Si interface. Compared with the ZrO{sub 2}-based memory devices with no or excessive fluorine treatment, the one with suitable fluorine-treatment time shows higher operating speed and better retention due to less resistance of built-in electric field (formed by trapped electrons) against electron injection from the substrate and smaller trap-assisted tunneling leakage, resulting from improved ZrO{sub 2}/SiO{sub 2} and SiO{sub 2}/Si interfaces.

  8. Two-dimensional water waves in the presence of a freely floating body: conditions for the absence of trapped modes

    E-Print Network [OSTI]

    Nikolay Kuznetsov

    2015-03-07T23:59:59.000Z

    The coupled motion is investigated for a mechanical system consisting of water and a body freely floating in it. Water occupies either a half-space or a layer of constant depth into which an infinitely long surface-piercing cylinder is immersed, thus allowing us to study two-dimensional modes. Under the assumption that the motion is of small amplitude near equilibrium, a linear setting is applicable and for the time-harmonic oscillations it reduces to a spectral problem with the frequency of oscillations as the spectral parameter. It is essential that one of the problem's relations is linear with respect to the parameter, whereas two others are quadratic with respect to it. Within this framework, it is shown that the total energy of the water motion is finite and the equipartition of energy holds for the whole system. On this basis, it is proved that no wave modes can be trapped provided their frequencies exceed a bound depending on cylinder's properties, whereas its geometry is subject to some restrictions and, in some cases, certain restrictions are imposed on the type of mode.

  9. Measurement of the Neutron Lifetime by Counting Trapped Protons in a Cold Neutron Beam

    E-Print Network [OSTI]

    J. S. Nico; M. S. Dewey; D. M. Gilliam; F. E. Wietfeldt; X. Fei; W. M. Snow; G. L. Greene; J. Pauwels; R. Eykens; A. Lamberty; J. Van Gestel; R. D. Scott

    2004-11-19T23:59:59.000Z

    A measurement of the neutron lifetime $\\tau_{n}$ performed by the absolute counting of in-beam neutrons and their decay protons has been completed. Protons confined in a quasi-Penning trap were accelerated onto a silicon detector held at a high potential and counted with nearly unit efficiency. The neutrons were counted by a device with an efficiency inversely proportional to neutron velocity, which cancels the dwell time of the neutron beam in the trap. The result is $\\tau_{n} = (886.6\\pm1.2{\\rm [stat]}\\pm3.2{\\rm [sys]})$ s, which is the most precise measurement of the lifetime using an in-beam method. The systematic uncertainty is dominated by neutron counting, in particular the mass of the deposit and the $^{6}$Li({\\it{n,t}}) cross section. The measurement technique and apparatus, data analysis, and investigation of systematic uncertainties are discussed in detail.

  10. Storage of fiber-guided light in a nanofiber-trapped ensemble of cold atoms

    E-Print Network [OSTI]

    C. Sayrin; C. Clausen; B. Albrecht; P. Schneeweiss; A. Rauschenbeutel

    2015-02-04T23:59:59.000Z

    Tapered optical fibers with a nanofiber waist are versatile tools for interfacing light and matter. In this context, laser-cooled atoms trapped in the evanescent field surrounding the optical nanofiber are of particular interest: They exhibit both long ground-state coherence times and efficient coupling to fiber-guided fields. Here, we demonstrate electromagnetically induced transparency, slow light, and the storage of fiber-guided optical pulses in an ensemble of cold atoms trapped in a nanofiber-based optical lattice. We measure a slow-down of light pulses to group velocities of 50 m/s. Moreover, we store optical pulses at the single photon level and retrieve them on demand in the fiber after 2 microseconds with an overall efficiency of (3.0 +/- 0.4) %. Our results show that nanofiber-based interfaces for cold atoms have great potential for the realization of building blocks for future optical quantum information networks.

  11. Using malaise traps to sample ground beetles (Coleoptera: Carabidae).

    SciTech Connect (OSTI)

    Ulyshen, Michael D., James L. Hanula, and Scott Horn

    2005-01-01T23:59:59.000Z

    Pitfall traps provide an easy and inexpensive way to sample ground-dwelling arthropods (Spence and Niemela 1994; Spence et al. 1997; Abildsnes and Tommeras 2000) and have been used exclusively in many studies of the abundance and diversity of ground beetles (Coleoptera: Carabidae). Despite the popularity of this trapping technique, pitfall traps have many disadvantages. For example, they often fail to collect both small (Spence and Niemela 1994) and �¢����trap-shy�¢��� species (Benest 1989), eventually deplete the local carabid population (Digweed et al. 1995), require a species to be ground-dwelling in order to be captured (Liebherr and Mahar 1979), and produce different results depending on trap diameter and material, type of preservative used, and trap placement (Greenslade 1964; Luff 1975; Work et al. 2002). Further complications arise from seasonal patterns of movement among the beetles themselves (Maelfait and Desender 1990), as well as numerous climatic factors, differences in plant cover, and variable surface conditions (Adis 1979). Because of these limitations, pitfall trap data give an incomplete picture of the carabid community and should be interpreted carefully. Additional methods, such as use of Berlese funnels and litter washing (Spence and Niemela 1994), collection from lights (Usis and MacLean 1998), and deployment of flight intercept devices (Liebherr and Mahar 1979; Paarmann and Stork 1987), should be incorporated in surveys to better ascertain the species composition and relative numbers of ground beetles. Flight intercept devices, like pitfall traps, have the advantage of being easy to use and replicate, but their value to carabid surveys is largely unknown. Here we demonstrate the effectiveness of Malaise traps for sampling ground beetles in a bottomland hardwood forest.

  12. Trap seal for open circuit liquid cooled turbines

    DOE Patents [OSTI]

    Grondahl, Clayton M. (Clifton Park, NY); Germain, Malcolm R. (Ballston Lake, NY)

    1980-01-01T23:59:59.000Z

    An improved trap seal for open circuit liquid cooled turbines is disclosed. The trap seal of the present invention includes an annular recess formed in the supply conduit of cooling channels formed in the airfoil of the turbine buckets. A cylindrical insert is located in the annular recesses and has a plurality of axial grooves formed along the outer periphery thereof and a central recess formed in one end thereof. The axial grooves and central recess formed in the cylindrical insert cooperate with the annular recess to define a plurality of S-shaped trap seals which permit the passage of liquid coolant but prohibit passage of gaseous coolant.

  13. Constitutive Model for the Time-Dependent Mechanical Behavior of 430 Stainless Steel and FeCrAlY Foams in Sulfur-Bearing Environments

    SciTech Connect (OSTI)

    Hemrick, James Gordon [ORNL; Lara-Curzio, Edgar [ORNL

    2013-01-01T23:59:59.000Z

    The mechanical behavior of 430 stainless steel and pre-oxidized FeCrAlY open-cell foam materials of various densities was evaluated in compression at temperatures between 450 C and 600 C in an environment containing hydrogen sulfide and water vapor. Both materials showed negligible corrosion due to the gaseous atmosphere for up to 168 hours. The monotonic stress-strain response of these materials was found to be dependent on both the strain rate and their density, and the 430 stainless steel foam materials exhibited less stress relaxation than FeCrAlY for similar experimental conditions. Using the results from multiple hardening-relaxation and monotonic tests, an empirical constitutive equation was derived to predict the stress-strain behavior of FeCrAlY foams as a function of temperature and strain rate. These results are discussed in the context of using these materials in a black liquor gasifier to accommodate the chemical expansion of the refractory liner resulting from its reaction with the soda in the black liquor.

  14. Novel trapping techniques for shaping Bose-Einstein condensates

    E-Print Network [OSTI]

    Boyd, Micah (Micah Scott)

    2007-01-01T23:59:59.000Z

    A combination of radio frequency radiation and magnetic field gradients was used to trap atoms in dressed states. In a magnetic field with a quadrupole minimum. RF fields resonant with the (I F. m)) 11. -1) -- 1, 0) ...

  15. Mass Spectrometer: Linear Ion Trap Quadrupole (LTQ) Orbitrap...

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

    Ion Trap Quadrupole (LTQ) Orbitrap MS - for environmental research (nanoDESI) Instrument ID: 34068 Availability: 10 hours a day, 5 days a week Quick Specs Science Contact Science...

  16. A bosonic Josephson junction controlled by a single trapped ion

    E-Print Network [OSTI]

    Gerritsma, R; Doerk, H; Idziaszek, Z; Calarco, T; Schmidt-Kaler, F

    2011-01-01T23:59:59.000Z

    We theoretically investigate the properties of a double-well bosonic Josephson junction coupled to a single trapped ion. We find that the coupling between the wells can be controlled by the internal state of the ion, which can be used for studying mesoscopic entanglement between the two systems and to measure their interaction with high precision. As a particular example we consider a small $^{87}$Rb Bose-Einstein condensate controlled by a single $^{171}$Yb$^+$ ion. We calculate interwell coupling rates reaching 100 Hz, while the state dependence amounts to 10s of Hz for plausible values of the currently unknown s-wave scattering length between the atom and the ion. The system could be realized in an experiment by combining trapped ions with optical dipole traps for cold atoms or in a combined atom-ion micro trap, where both approaches are within reach using current technology.

  17. NOx Adsorber (Lean NOx Trap) Fundamentals (Agreement #10049 ...

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

    on catalyst structure changes * Roles of catalyst promoters (e.g., J.R. Theis, et al., "The effect of Ceria Content on the Performance of a NOx Trap", SAE 2003-01-1160) - On...

  18. Brief Communication 1195 A gene trap approach in Xenopus

    E-Print Network [OSTI]

    Amaya, Enrique

    developed several gene trap vectors, using the green fluorescent protein (GFP) as a marker. Using, including expression in the epiphysis, the olfactory bulb and placodes, the eyes, ear, brain, muscles, tail

  19. advanced ion trap: Topics by E-print Network

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

    geometry that generates a two dimensional lattice of point Paul traps. C. E. Pearson; D. R. Leibrandt; W. S. Bakr; W. J. Mallard; K. R. Brown; I. L. Chuang 2005-11-02 17 Cold...

  20. Light trapping limits in plasmonic solar cells: an analytical investigation

    E-Print Network [OSTI]

    Sheng, Xing

    We analytically investigate the light trapping performance in plasmonic solar cells with Si/metallic structures. We consider absorption enhancements for surface plasmon polaritons (SPPs) at planar Si/metal interfaces and ...

  1. Quantum gates, sensors, and systems with trapped ions

    E-Print Network [OSTI]

    Wang, Shannon Xuanyue

    2012-01-01T23:59:59.000Z

    Quantum information science promises a host of new and useful applications in communication, simulation, and computational algorithms. Trapped atomic ions are one of the leading physical systems with potential to implement ...

  2. Light Trapping, Absorption and Solar Energy Harvesting by Artificial Materials

    SciTech Connect (OSTI)

    John, Sajeev [University of Toronto

    2014-08-15T23:59:59.000Z

    We provide designs of thin-film solar cells utilizing optimized photonic-crystal light-trapping and numerical simulations of their solar-to-electrical power conversion efficiencies.

  3. Laser ablation loading of a surface-electrode ion trap

    E-Print Network [OSTI]

    David R. Leibrandt; Robert J. Clark; Jaroslaw Labaziewicz; Paul Antohi; Waseem Bakr; Kenneth R. Brown; Isaac L. Chuang

    2007-06-22T23:59:59.000Z

    We demonstrate loading by laser ablation of $^{88}$Sr$^+$ ions into a mm-scale surface-electrode ion trap. The laser used for ablation is a pulsed, frequency-tripled Nd:YAG with pulse energies of 1-10 mJ and durations of 3-5 ns. An additional laser is not required to photoionize the ablated material. The efficiency and lifetime of several candidate materials for the laser ablation target are characterized by measuring the trapped ion fluorescence signal for a number of consecutive loads. Additionally, laser ablation is used to load traps with a trap depth (40 meV) below where electron impact ionization loading is typically successful ($\\gtrsim$ 500 meV).

  4. Low temperature cold trapping of uranium hexafluoride containing hydrogen fluoride

    SciTech Connect (OSTI)

    Hobbs, W.E.; Barber, E.J.; Jones, C.G.

    1990-10-01T23:59:59.000Z

    The use of a freezer-sublimer system operating at low desublimation pressures to replace 10-in. nuclearly safe cold traps for low assay (<5% U-235) uranium hexafluoride (UF{sub 6}) would significantly simplify operations and is economically attractive provided the nuclear safety of the system can be assured. A major requirement of such assurance is the availability of conditions guaranteeing that the nuclear safety design criterion, which requires that the H/U atomic ratio in the condensate in the freezer-sublimer always be less than 0.33 for assays up to 5%, will never be violated. A general vapor pressure equation giving the vapor pressure of HF-UF{sub 6} solutions as a function of temperature and mole fraction UF{sub 6} has been developed. The precision of the data at the 95% confidence level is {plus minus}0.1 torr at temperatures between {minus}100{degree}F and {minus}121{degree}F. The calculated vapor pressure of pure HF is 4.6 torr at {minus}100{degree}F and 3.1 torr at {minus}108{degree}F. Theoretical considerations suggest that the true value will be slightly lower. In experimental studies of the cold trapping operation at {minus}108{degree}F and at a trap pressure of 2.2 torr, only 7.3% of the HF entering the trap was retained in the trap. At a trap pressure of 4.6 torr, over 80% of the HF entering the trap was retained. The data obtained in this study confirms that the physical chemistry of the HF-UF{sub 6} system previously developed accurately describes the behavior of the system and that so long as the pressure in the trap is maintained below the vapor pressure of pure HF at the trap temperatures, there is no way that sufficient HF can be trapped to give an H/U ratio of 0.33 regardless of the HF/UF{sub 6} ratio in the feed to the trap. 5 refs., 4 tabs.

  5. Trapped surfaces in Oppenheimer-Snyder black holes

    E-Print Network [OSTI]

    Ingemar Bengtsson; Emma Jakobsson; José M. M. Senovilla

    2013-06-27T23:59:59.000Z

    The Oppenheimer-Snyder solution models a homogeneous round dust cloud collapsing to a black hole. Inside its event horizon there is a region through which trapped surfaces pass. We try to determine exactly where the boundary of this region meets the centre of the cloud. We present explicit examples of the relevant trapped (topological) spheres; they extend into the exterior vacuum region, and are carefully matched at the junction between the cloud and the vacuum.

  6. The Engineered Approach to Energy and Maintenance Effective Steam Trapping

    E-Print Network [OSTI]

    Krueger, R. G.; Wilt, G. W.

    1980-01-01T23:59:59.000Z

    ., Chemical Engineering 9/1/75. 4. Maintenance Engineering, May 1976. 5. "How Much Does Lost Steam Cost",Armstrong Machine works, Hydrocarbon Processing, p.129, Jan. 1976. 6. "Setter Steam Trapping Cuts Energy Waste", wesley Yates, Yarway Corp..., Georgia Tech Industrial Energy Extension Service, Chemical Engineering, 2/11/80. 10. ''Basic Facts & Enerqv Saving Tips" ,Lawrence R. O'Dell, Armstrong Machine Works, Heating/Piping/ Air Conditioning, May 1977. 11. Steam Trap Report - Energy Loss...

  7. Design and operation of the electron beam ion trap

    SciTech Connect (OSTI)

    Vogel, D.

    1990-05-30T23:59:59.000Z

    This report describes the basic features and operating principles of the Electron Beam Ion Trap. The differences between EBIT and other sources of highly charged ions are outlined. Its features and operating parameters are discussed. The report also explains why certain design choices were necessary and the constraints involved in building an electron beam ion trap. EBIT's evaporation cooling system is described in detail. 13 refs., 8 figs.

  8. Laser induced rotation of trapped chiral and achiral nematic droplets

    E-Print Network [OSTI]

    Marjan Mosallaeipour; Yashodhan Hatwalne; N. V. Madhusudana; Sharath Ananthamurthy

    2010-02-05T23:59:59.000Z

    We study the response of optically trapped achiral and chiralised nematic liquid crystal droplets to linear as well as circular polarised light. We find that there is internal dissipation in rotating achiral nematic droplets trapped in glycerine. We also demonstrate that some chiralised droplets rotate under linearly polarised light. The best fit to our data on chiralised droplets indicates that rotational frequency of these droplets with radius R is approximately proportional to1/R^2, rather than to 1/R^3.

  9. Global sound modes in mirror traps with anisotropic pressure

    SciTech Connect (OSTI)

    Skovorodin, D. I.; Zaytsev, K. V.; Beklemishev, A. D. [Budker Institute of Nuclear Physics, Novosibirsk State University, Novosibirsk 630090 (Russian Federation)] [Budker Institute of Nuclear Physics, Novosibirsk State University, Novosibirsk 630090 (Russian Federation)

    2013-10-15T23:59:59.000Z

    Global oscillations of inhomogeneous plasma with frequencies close to the bounce frequency of ions in mirror traps have been studied. It has been shown that, in some cases, the sound can be reflected from the axial plasma inhomogeneity. The ideal magnetohydrodynamic (MHD) model with Chew-Goldberger-Low approximation has been utilized to determine conditions of existence of the standing waves in the mirror-confined plasma. Linearized wave equation for the longitudinal plasma oscillations in thin anisotropic inhomogeneous plasma with finite ? has been derived. The wave equation has been treated numerically. The oscillations are studied for the case of the trap with partially filled loss-cone and the trap with sloshing ions. It has been shown that in cells of the multiple-mirror trap standing waves can exist. The frequency of the wave is of the order of the mean bounce-frequency of ions. In the trap with sloshing ions, the mode supported by the pressure of fast ions could exist. The results of oscillations observation in the experiment on the Gas Dynamic Trap have been presented.

  10. Thermal Trap for DNA Replication Christof B. Mast and Dieter Braun*

    E-Print Network [OSTI]

    Kersting, Roland

    and simultaneously accumulates the replicated molecules in an efficient thermophoretic trap. The non- equilibrium

  11. Trapping of Single Nano-objects in Dynamic Temperature Fields Marco Braun and Frank Cichos

    E-Print Network [OSTI]

    Boyer, Edmond

    is considered. The present study complements the dynamic thermophoretic trapping with a theoretical basis

  12. Trapped-ion cell with improved DC potential harmonicity for FT-ICR MS

    SciTech Connect (OSTI)

    Tolmachev, Aleksey V.; Robinson, Errol W.; Wu, Si; Kang, Hyuk; Lourette, Natacha M.; Pasa-Tolic, Ljiljana; Smith, Richard D.

    2008-04-01T23:59:59.000Z

    The trapped-ion cell is a key component critical for optimal performance in Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry (MS). We have upgraded our 12 Tesla FT-ICR instrument with a new open cylindrical cell that includes four additional cylindrical segments that serve as compensation electrodes. The DC potential on the additional segments can be set to specific pre-calculated values to suppress DC trapping field anharmonicity, in an effort to improve coherence of the ion cyclotron motion and minimize deviations from the calibration function of the ideal cell. Alternatively, the compensation potentials can be set equal to potentials of adjacent cell electrodes, which creates a DC potential distribution equivalent to that of a regular open cylindrical cell. The initial experimental characterization of both the compensated and open cell configurations was performed using ESI direct infusion of a peptide mixture. Operating the compensated cell at increased post-excitation radii resulted in improved mass measurement accuracy together with increased signal intensity, while the regular configuration exhibited peak splitting and reduced signal life time under these operating conditions. The observed improvement of the compensated cell performance was consistent with the expected behavior due to the improved DC potential harmonicity. These results confirm that the trapping DC potential harmonicity is significant for optimizing FT-ICR MS performance.

  13. Ion-trap measurements of electric-field noise near surfaces

    E-Print Network [OSTI]

    M. Brownnutt; M. Kumph; P. Rabl; R. Blatt

    2014-09-23T23:59:59.000Z

    Electric-field noise near surfaces is a common problem in diverse areas of physics, and a limiting factor for many precision measurements. There are multiple mechanisms by which such noise is generated, many of which are poorly understood. Laser-cooled, trapped ions provide one of the most sensitive systems to probe electric-field noise at MHz frequencies and over a distance range 30 - 3000 $\\mu$m from the surface. Over recent years numerous experiments have reported spectral densities of electric-field noise inferred from ion heating-rate measurements and several different theoretical explanations for the observed noise characteristics have been proposed. This paper provides an extensive summary and critical review of electric-field noise measurements in ion traps, and compares these experimental findings with known and conjectured mechanisms for the origin of this noise. This reveals that the presence of multiple noise sources, as well as the different scalings added by geometrical considerations, complicate the interpretation of these results. It is thus the purpose of this review to assess which conclusions can be reasonably drawn from the existing data, and which important questions are still open. In so doing it provides a framework for future investigations of surface-noise processes.

  14. Respiratory Mechanisms of Support

    E-Print Network [OSTI]

    Kay, Mark A.

    Respiratory Mechanisms of Support Nasal Cannula Hi Flow Nasal Cannula CPAP Continuous positive the respiratory system is working to compensate for a metabolic issue so as to normalize the blood pH. HCO3 - 22 uses PIP Mechanical Ventilation: Volume vs. Pressure: Volume Control Pressure Control Cycle Volume Time

  15. Quantum Mechanical Clock and Classical Relativistic Clock

    E-Print Network [OSTI]

    Hitoshi Kitada

    2004-07-08T23:59:59.000Z

    A cyclic nature of quantum mechanical clock is discussed as ``quantization of time." Quantum mechanical clock is seen to be equivalent to the relativistic classical clock.

  16. Characteristics of trap-filled gallium arsenide photoconductive switches used in high gain pulsed power applications

    SciTech Connect (OSTI)

    ISLAM,N.E.; SCHAMILOGLU,E.; MAR,ALAN; LOUBRIEL,GUILLERMO M.; ZUTAVERN,FRED J.; JOSHI,R.P.

    2000-05-30T23:59:59.000Z

    The electrical properties of semi-insulating (SI) Gallium Arsenide (GaAs) have been investigated for some time, particularly for its application as a substrate in microelectronics. Of late this material has found a variety of applications other than as an isolation region between devices, or the substrate of an active device. High resistivity SI GaAs is increasingly being used in charged particle detectors and photoconductive semiconductor switches (PCSS). PCSS made from these materials operating in both the linear and non-linear modes have applications such as firing sets, as drivers for lasers, and in high impedance, low current Q-switches or Pockels cells. In the non-linear mode, it has also been used in a system to generate Ultra-Wideband (UWB) High Power Microwaves (HPM). The choice of GaAs over silicon offers the advantage that its material properties allow for fast, repetitive switching action. Furthermore photoconductive switches have advantages over conventional switches such as improved jitter, better impedance matching, compact size, and in some cases, lower laser energy requirement for switching action. The rise time of the PCSS is an important parameter that affects the maximum energy transferred to the load and it depends, in addition to other parameters, on the bias or the average field across the switch. High field operation has been an important goal in PCSS research. Due to surface flashover or premature material breakdown at higher voltages, most PCSS, especially those used in high power operation, need to operate well below the inherent breakdown voltage of the material. The lifetime or the total number of switching operations before breakdown, is another important switch parameter that needs to be considered for operation at high bias conditions. A lifetime of {approximately} 10{sup 4} shots has been reported for PCSS's used in UWB-HPM generation [5], while it has exceeded 10{sup 8} shots for electro-optic drivers. Much effort is currently being channeled in the study related to improvements of these two parameters high bias operation and lifetime improvement for switches used in pulsed power applications. The contact material and profiles are another important area of study. Although these problems are being pursued through the incorporation of different contact materials and introducing doping near contacts, it is important that the switch properties and the conduction mechanism in these switches be well understood such that the basic nature of the problems can be properly addressed. In this paper the authors report on these two basic issues related to the device operation, i.e., mechanisms for increasing the hold-off characteristics through neutron irradiation, and the analysis of transport processes at varying field conditions in trap dominated SI GaAs in order to identify the breakdown mechanism during device operation. It is expected that this study would result in a better understanding of photoconductive switches, specifically those used in high power operation.

  17. Born-Oppenheimer description of two atoms in a combined oscillator and lattice trap

    E-Print Network [OSTI]

    Ole Søe Sørensen; Klaus Mølmer

    2012-06-26T23:59:59.000Z

    We analyze the quantum states of two atoms in a combined harmonic oscillator and periodic lattice trap in one spatial dimension. In the case of tight-binding and only nearest neighbor tunneling, the equations of motion are conveniently represented in the momentum representation. We show that in the case of strong attraction between the particles, the di?erent time scales of relative and center-of-mass motion validate a separation of the problem similar to the Born-Oppenheimer approximation applied in the description of electronic and nuclear motion in molecules.

  18. Quantum feedback cooling of a single trapped ion in front of a mirror

    E-Print Network [OSTI]

    V. Steixner; P. Rabl; P. Zoller

    2005-06-22T23:59:59.000Z

    We develop a theory of quantum feedback cooling of a single ion trapped in front of a mirror. By monitoring the motional sidebands of the light emitted into the mirror mode we infer the position of the ion, and act back with an appropriate force to cool the ion. We derive a feedback master equation along the lines of the quantum feedback theory developed by Wiseman and Milburn, which provides us with cooling times and final temperatures as a function of feedback gain and various system parameters.

  19. Revealing the escape mechanism of three-dimensional orbits in a tidally limited star cluster

    E-Print Network [OSTI]

    Euaggelos E. Zotos

    2014-11-18T23:59:59.000Z

    The aim of this work is to explore the escape process of three-dimensional orbits in a star cluster rotating around its parent galaxy in a circular orbit. The gravitational field of the cluster is represented by a smooth, spherically symmetric Plummer potential, while the tidal approximation was used to model the steady tidal field of the galaxy. We conduct a thorough numerical analysis distinguishing between regular and chaotic orbits as well as between trapped and escaping orbits, considering only unbounded motion for several energy levels. It is of particular interest to locate the escape basins towards the two exit channels and relate them with the corresponding escape times of the orbits. For this purpose, we split our investigation into three cases depending on the initial value of the $z$ coordinate which was used for launching the stars. The most noticeable finding is that the majority of stars initiated very close to the primary $(x,y)$ plane move in chaotic orbits and they remain trapped for vast time intervals, while orbits with relatively high values of $z_0$ on the other hand, form well-defined basins of escape. It was also observed, that for energy levels close to the critical escape energy the escape rates of orbits are large, while for much higher values of energy most of the orbits have low escape periods or they escape immediately to infinity. We hope our outcomes to be useful for a further understanding of the dissolution process and the escape mechanism in open star clusters.

  20. Trapped-flux internal-dipole superconducting motor/generator.

    SciTech Connect (OSTI)

    Hull, J. R.

    1998-09-03T23:59:59.000Z

    A new class of motor/generator (M/G) utilizes the magnetic flux trapping capability of high-temperature superconductors (HTSs). The rotor, consists of a cylindrical shell composed of HTS segments. These segments act as trapped-field magnets, magnetized in such a way that a dipole magnetic field is produced in the interior of the shell. A stator coil assembly is placed in the interior of the shell and current passing through the conductors of the coil produce a rotational torque, either as a hysteresis motor or as a synchronous motor. The coil may be either conventional, with copper wires and an iron core, or composed of superconductors and can be used to establish the trapped fields in the HTSs.

  1. Absorption by cold Fermi atoms in a harmonic trap

    E-Print Network [OSTI]

    Gediminas Juzeliunas; Marius Masalas

    2000-11-10T23:59:59.000Z

    We study the absorption spectrum for a strongly degenerate Fermi gas confined in a harmonic trap. The spectrum is calculated using both the exact summation and also the Thomas-Fermi (TF) approximation. In the latter case, relatively simple analytical expressions are obtained for the absorption lineshape at large number of trapped atoms. At zero temperature, the approximated lineshape is characterized by a $(1-z^2)^{5/2}$ dependence which agrees well with the exact numerical calculations. At non-zero temperature, the spectrum becomes broader, although remains non-Gaussian as long as the fermion gas is degenerate. The changes in the trap frequency for an electronically excited atom can introduce an additional line broadening.

  2. Recent progress in tailoring trap-based positron beams

    SciTech Connect (OSTI)

    Natisin, M. R.; Hurst, N. C.; Danielson, J. R.; Surko, C. M. [Physics Department, University of California, San Diego La Jolla CA 92093-0319 (United States)

    2013-03-19T23:59:59.000Z

    Recent progress is described to implement two approaches to specially tailor trap-based positron beams. Experiments and simulations are presented to understand the limits on the energy spread and pulse duration of positron beams extracted from a Penning-Malmberg (PM) trap after the particles have been buffer-gas cooled (or heated) in the range of temperatures 1000 {>=} T {>=} 300 K. These simulations are also used to predict beam performance for cryogenically cooled positrons. Experiments and simulations are also presented to understand the properties of beams formed when plasmas are tailored in a PM trap in a 5 tesla magnetic field, then non-adiabatically extracted from the field using a specially designed high-permeability grid to create a new class of electrostatically guided beams.

  3. Coulomb crystal mass spectrometry in a digital ion trap

    E-Print Network [OSTI]

    Deb, Nabanita; Smith, Alexander D; Keller, Matthias; Rennick, Christopher J; Heazlewood, Brianna R; Softley, Timothy P

    2015-01-01T23:59:59.000Z

    We present a mass spectrometric technique for identifying the masses and relative abundances of Coulomb-crystallized ions held in a linear Paul trap. A digital radiofrequency waveform is employed to generate the trapping potential, as this can be cleanly switched off, and static dipolar fields subsequently applied to the trap electrodes for ion ejection. Excellent detection efficiency is demonstrated for Ca+ and CaF+ ions from bi-component Ca+/CaF+ Coulomb crystals prepared by reaction of Ca+ with CH3F. A quantitative linear relationship is observed between ion number and the corresponding integrated TOF peak, independent of the ionic species. The technique is applicable to a diverse range of multi-component Coulomb crystals - demonstrated here for Ca+/NH3+/NH4+ and Ca+/CaOH+/CaOD+ crystals - and will facilitate the measurement of ion-molecule reaction rates and branching ratios in complicated reaction systems.

  4. Cascade phonon-assisted trapping of positrons by divacancies in n-FZ-Si(P) single crystals irradiated with 15 MeV protons

    SciTech Connect (OSTI)

    Arutyunov, N. Yu., E-mail: n-arutyunov@yahoo.com [Martin Luther University Halle, Department of Physics, 06120 Halle, Germany and Inst. of Ion-Plasma and Laser Technologies (Inst. of Electronics), 700187 Tashkent (Uzbekistan); Emtsev, V. V.; Oganesyan, G. A. [Ioffe Physico-Technical Institute, 194021 St. Petersburg (Russian Federation); Krause-Rehberg, R.; Kessler, C. [Martin Luther University Halle, Department of Physics, 06120 Halle (Germany); Elsayed, M. [Martin Luther University Halle, Department of Physics, 06120 Halle, Germany and Minia university, Faculty of Science, Physics Department, P.O. box 61519 Minia (Egypt); Kozlovski, V. V. [St. Petersburg State Polytechnic University, 195251 St. Petersburg (Russian Federation)

    2014-02-21T23:59:59.000Z

    The trapping of positrons by the radiation defects in moderately doped oxygen-lean n-FZ-Si(P) single crystal irradiated with 15 MeV protons has been investigated in a comparative way using the positron lifetime spectroscopy and Hall effect measurements. The experiments were carried out within a wide temperature interval ranging from 25 K – 29 K to 300 K. The positron trapping rate for divacancies was reconstructed in the course of many-stage isochronal annealing. The concentration and the charged states of divacancies (V{sub 2}{sup ?} and V{sub 2}{sup ??}) were estimated. The temperature dependency of the trapping cross section of positrons by the negatively charged divacancies is in a good agreement with the data of calculations based on the assumptions of the cascade phonon-assisted mechanism of exchange of the energy between the positron and acoustic long-wave phonons. Obeying ? T{sup ?3} law, the cross-section of the trapping of positrons by divacancies changes considerably ranging from ?1.7×10{sup ?12} cm{sup 2} (66 – 100 K) to ?2×10{sup ?14} cm{sup 2} (? 250 K). The characteristic length of trapping of the positron by V{sub 2}{sup ??} divacancy was estimated to be l{sub 0}(V{sub 2}{sup ??})?(3.4±0.2)×10{sup ?8} cm.

  5. Selection, Sizing, and Testing of Stream Traps in Commercial Buildings

    E-Print Network [OSTI]

    Armer, A.; Risko, J. R.

    1984-01-01T23:59:59.000Z

    waterhammer exists, and until it is erad- icated, the use of the float and thermostatic trap is to be avoSded because the ball float can be damaged by waterhammer. Inverted bucket traps can also discharge conden- sate at steam temperature, almost... is acceptable, and encourage using the steam's sensible heat as well as the latent heat. Typical uses are some storage coils, but they also can be used to drain condensate from dead ends in systems to prevent freezing when steam is shut down, or waterhammer...

  6. What To Do With Cold Traps and Why

    E-Print Network [OSTI]

    Risko, J. R.; Walter, J. P.

    2012-01-01T23:59:59.000Z

    of the 2012 Industrial Energy Technology Conference New Orleans, Louisiana, May 29-June 1, 2012 TABLE!1 Failure!Event Historical!Value Flare!Nozzle!Replacement $750,000! Analyzer!Failure!Plant!Shutdown $1,000,000! Flare"out!Fine $1,700,000! Gas... Orleans, Louisiana, May 29-June 1, 2012 TABLE!7 Failure!Events Annual!Cost!/!Trap (360!Traps!in!Unit) Flare!Nozzle!Replacement $694 Analyzer!Failure!Shuts!Plant $1,389 Flare"out!Fine $3,148 Gas!Compressor!Failure $5,000 Main!Turbine!Failure $11...

  7. Ion trapping in the emitter sheath in thermionic converters

    SciTech Connect (OSTI)

    Lundgren, L.

    1985-12-01T23:59:59.000Z

    The effect of ion trapping in the emitter sheath in ignited thermionic converters is studied. The ion trapping prevents the emitter-sheath barrier from being higher than approximately 0.1 eV, when the current decreases in the converter. This gives a condition for the constriction of the arc. I-V curves are calculated for an ignited thermionic converter with a hydrodynamic plasma theory that takes into account the effect of Coulomb scattering and volume recombination, but assumes that the electron temperature is constant in the plasma.

  8. Independent trapping and manipulation of microparticles using dexterous acoustic tweezers

    SciTech Connect (OSTI)

    Courtney, Charles R. P., E-mail: c.r.p.courtney@bath.ac.uk [Department of Mechanical Engineering, University of Bath, Bath (United Kingdom); Demore, Christine E. M.; Wu, Hongxiao; Cochran, Sandy [Institute of Medical Science and Technology, University of Dundee, Dundee (United Kingdom); Grinenko, Alon; Wilcox, Paul D.; Drinkwater, Bruce W. [Department of Mechanical Engineering, University of Bristol, Bristol (United Kingdom)

    2014-04-14T23:59:59.000Z

    An electronically controlled acoustic tweezer was used to demonstrate two acoustic manipulation phenomena: superposition of Bessel functions to allow independent manipulation of multiple particles and the use of higher-order Bessel functions to trap particles in larger regions than is possible with first-order traps. The acoustic tweezers consist of a circular 64-element ultrasonic array operating at 2.35?MHz which generates ultrasonic pressure fields in a millimeter-scale fluid-filled chamber. The manipulation capabilities were demonstrated experimentally with 45 and 90-?m-diameter polystyrene spheres. These capabilities bring the dexterity of acoustic tweezers substantially closer to that of optical tweezers.

  9. Magneto-optical trapping of potassium isotopes

    E-Print Network [OSTI]

    Walker, Thad G.

    managed to fool nearly everyone with outrageous but nearly believable stories. On the more serious side and good spirits have made the past few demanding months of this project much more bearable. Of course, he've thoroughly enjoyed the time spent working with both of these guys in the labs, building and learning. Ren

  10. Narrowing of the coherent population trapping resonance under zone pumping in cells with different characteristics of the wall coating

    SciTech Connect (OSTI)

    Kazakov, G A; Litvinov, A N; Matisov, B G [St. Petersburg State Polytechnic University, St. Petersburg (Russian Federation)

    2012-02-28T23:59:59.000Z

    It is shown that when coherent population trapping (CPT) resonance is excited by a narrow laser beam, the presence of elastic collisions with the cell wall significantly affects the line shape of the CPT-resonance. We have constructed a theoretical model, which is based on averaging over the random Ramsey sequences of the atom dwell time in the beam and dark zones and takes into account the probability of elastic bounce of an atom from the wall.

  11. Enhancing DNA binding rate using optical trapping of high-density gold nanodisks

    SciTech Connect (OSTI)

    Lin, En-Hung; Pan, Ming-Yang [Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, Taiwan 30013 (China) [Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, Taiwan 30013 (China); Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan 11529 (China); Lee, Ming-Chang [Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, Taiwan 30013 (China)] [Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, Taiwan 30013 (China); Wei, Pei-Kuen, E-mail: pkwei@sinica.edu.tw [Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan 11529 (China) [Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan 11529 (China); Institute of Biophotonics, National Yang-Ming University, Taipei 11221, Taiwan (China)

    2014-03-15T23:59:59.000Z

    We present the dynamic study of optical trapping of fluorescent molecules using high-density gold nanodisk arrays. The gold nanodisks were fabricated by electron beam lithography with a diameter of 500 nm and a period of 1 ?m. Dark-field illumination showed ?15 times enhancement of fluorescence near edges of nanodisks. Such enhanced near-field generated an optical trapping force of ?10 fN under 3.58 × 10{sup 3} W/m{sup 2} illumination intensity as calculated from the Brownian motions of 590 nm polystyrene beads. Kinetic observation of thiolated DNA modified with Cy5 dye showed different binding rates of DNA under different illumination intensity. The binding rate increased from 2.14 × 10{sup 3} s{sup ?1} (I = 0.7 × 10{sup 3} W/m{sup 2}) to 1.15 × 10{sup 5} s{sup ?1} (I = 3.58 × 10{sup 3} W/m{sup 2}). Both enhanced fluorescence and binding rate indicate that gold nanodisks efficiently improve both detection limit and interaction time for microarrays.

  12. Measuring the Neutron Lifetime Using Magnetically Trapped Neutrons

    E-Print Network [OSTI]

    O'Shaughnessy, C M; Schelhammer, K W; Swank, C M; Seo, P -N; Huffman, P R; Dzhosyuk, S N; Mattoni, C E H; Yang, L; Doyle, J M; Coakley, K J; Thompson, A K; Mumm, H P; Lamoreaux, S K; Yang, G

    2009-01-01T23:59:59.000Z

    The neutron beta-decay lifetime plays an important role both in understanding weak interactions within the framework of the Standard Model and in theoretical predictions of the primordial abundance of 4He in Big Bang Nucleosynthesis. In previous work, we successfully demonstrated the trapping of ultracold neutrons (UCN) in a conservative potential magnetic trap. A major upgrade of the apparatus is nearing completion at the National Institute of Standards and Technology Center for Neutron Research (NCNR). In our approach, a beam of 0.89 nm neutrons is incident on a superfluid 4He target within the minimum field region of an Ioffe-type magnetic trap. A fraction of the neutrons is downscattered in the helium to energies <200 neV, and those in the appropriate spin state become trapped. The inverse process is suppressed by the low phonon density of helium at temperatures less than 200 mK, allowing the neutron to travel undisturbed. When the neutron decays the energetic electron ionizes the helium, producing sci...

  13. Non-Diversification Traps in Catastrophe Insurance Markets Rustam Ibragimov

    E-Print Network [OSTI]

    Chaudhuri, Sanjay

    markets, even though there is a large enough market capacity to reach full risk sharing throughNon-Diversification Traps in Catastrophe Insurance Markets Rustam Ibragimov Dwight Jaffee Johan Walden§ Abstract We develop a model for markets for catastrophic risk. The model explains why insurance

  14. The TITAN in-trap decay spectroscopy facility at TRIUMF

    E-Print Network [OSTI]

    K. G. Leach; A. Grossheim; A. Lennarz; T. Brunner; J. R. Crespo López-Urrutia; A. T. Gallant; M. Good; R. Klawitter; A. A. Kwiatkowski; T. Ma; T. D. Macdonald; S. Seeraji; M. C. Simon; C. Andreoiu; J. Dilling; D. Frekers

    2014-11-22T23:59:59.000Z

    This article presents an upgraded in-trap decay spectroscopy apparatus which has been developed and constructed for use with TRIUMF's Ion Trap for Atomic and Nuclear science (TITAN). This device consists of an open-access electron-beam ion-trap (EBIT), which is surrounded radially by seven low-energy planar Si(Li) detectors. The environment of the EBIT allows for the detection of low-energy photons by providing backing-free storage of the radioactive ions, while guiding charged decay particles away from the trap centre via the strong (up to 6 T) magnetic field. In addition to excellent ion confinement and storage, the EBIT also provides a venue for performing decay spectroscopy on highly-charged radioactive ions. Recent technical advancements have been able to provide a significant increase in sensitivity for low-energy photon detection, towards the goal of measuring weak electron-capture branching ratios of the intermediate nuclei in the two-neutrino double beta ($2\

  15. Trapping and Frequency Variability in Electron Acoustic Waves

    E-Print Network [OSTI]

    California at San Diego, University of

    Trapping and Frequency Variability in Electron Acoustic Waves C.F. Driscoll, F. Anderegg, D 92093 USA Abstract. Electron Acoustic Waves (EAWs) with a phase velocity less than twice the plasma Langmuir waves, and at large excitations resonance is observed over a broad range. Laser Induced

  16. Light Trapping in Solar Cells Using Resonant Nanostructures P. Spinelli

    E-Print Network [OSTI]

    van Rooij, Robert

    Light Trapping in Solar Cells Using Resonant Nanostructures P. Spinelli #12;Summary Photovoltaics solar cell is reduced, due to incomplete absorption of light. In this thesis, we investigate new ways of enhancing light absorption in Si solar cells by using nanostructures that show resonant interaction

  17. Low-density instability of multicomponent matter with trapped neutrinos

    SciTech Connect (OSTI)

    Mart, T.; Sulaksono, A. [Departemen Fisika, FMIPA, Universitas Indonesia, Depok 16424 (Indonesia)

    2008-08-15T23:59:59.000Z

    The effect of neutrino trapping on the longitudinal dielectric function at low densities has been investigated by using different relativistic mean-field models. Parameter sets G2 of Furnstahl-Serot-Tang and Z271 of Horowitz-Piekarewicz, along with the adjusted parameter sets of both models, have been used in this study. The role of the isovector adjustment and the effect of the Coulomb interaction have also been studied. The effect of the isovector adjustment is found to be more significant in the Horowitz-Piekarewicz model, not only in neutrinoless matter but also in matter with neutrino trapping. Although almost independent to the variation of the leptonic fraction, the instability region of matter with neutrino trapping is found to be larger. The presence of more protons and electrons compared to the neutrinoless case is the reason behind this finding. For parameter sets with soft equations of state at low density, the appearance of a large and negative {epsilon}{sub L}(q,q{sub 0}=0) in some parts of the edge of the instability region in matter with neutrino trapping is understood as a consequence of the fact that the Coulomb interaction produced by electron and proton interaction is larger than the repulsive isovector interaction created by the asymmetry between the proton and neutron numbers.

  18. Novel devices for analytical-scale isoelectric trapping separations

    E-Print Network [OSTI]

    Lim, Peniel Jason

    2009-05-15T23:59:59.000Z

    through buffering membranes whose pH values bracket the pI of the ampholytic component to be trapped in the compartment. The present small-scale instruments use plastics as their structural materials, which causes poor Joule heat dissipation...

  19. Classical thermodynamics of particles in harmonic traps Martin Ligarea

    E-Print Network [OSTI]

    Ligare, Martin

    , and the heat capacities. I also consider cyclic thermodynamic processes in a harmonically confined gas. © 2010 of state for a gas of N noninteract- ing particles in a rigid volume V is derived in almost every text and pressure vary with position within such traps, and the volume of the gas is not well defined

  20. Loading a planar RF Paul Trap from a cold Yb? source

    E-Print Network [OSTI]

    Shields, Brendan John

    2006-01-01T23:59:59.000Z

    In this thesis, we demonstrate a functioning planar radio frequency, three-rod Paul Trap, loaded with Yb+ ions that have been photoionized from a source of neutral atoms, which were cooled in a magneto-optical trap. Planar ...

  1. Comparison of traps and baits for censusing small mammals in Neotropical lowlands.

    E-Print Network [OSTI]

    Woodman, Neal; Timm, Robert M.; Slade, Norman A.; Doonan, Terry J.

    1996-02-01T23:59:59.000Z

    Snap-traps, live-traps, and baits affect the ability to capture small mammals, but few previous studies have involved sampling communities of small mammals in tropical environments. We tested differences in captures of small marsupials and rodents...

  2. Intra-catalyst Reductant Chemistry in Lean NOx Traps: A Study...

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

    Intra-catalyst Reductant Chemistry in Lean NOx Traps: A Study on Sulfur Effects Intra-catalyst Reductant Chemistry in Lean NOx Traps: A Study on Sulfur Effects Presentation given...

  3. Excellent Sulfur Resistance of Pt/BaO/CeO2 Lean NOx Trap Catalysts...

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

    NOx Trap Catalysts. Excellent Sulfur Resistance of PtBaOCeO2 Lean NOx Trap Catalysts. Abstract: In this work, we investigated the NOx storage behavior of Pt-BaOCeO2 catalysts,...

  4. Solar energy trapping with modulated silicon nanowire photonic crystals Guillaume Demsy and Sajeev John

    E-Print Network [OSTI]

    John, Sajeev

    Solar energy trapping with modulated silicon nanowire photonic crystals Guillaume Demésy and Sajeev://jap.aip.org/about/rights_and_permissions #12;Solar energy trapping with modulated silicon nanowire photonic crystals Guillaume Demesya

  5. Enumeration of Juvenile Salmonids in the Okanogan Basin Using Rotary Screw Traps, Performance Period: March 15, 2006 - July 15, 2006.

    SciTech Connect (OSTI)

    Johnson, Peter N.; Rayton, Michael D.

    2007-05-01T23:59:59.000Z

    The Colville Tribes identified the need for collecting baseline census data on the timing and abundance of juvenile salmonids in the Okanogan River basin for the purpose of documenting local fish populations, augmenting existing fishery data and assessing natural production trends of salmonids. This report documents and assesses the pilot year of rotary trap capture of salmonid smolts on the Okanogan River. The project is a component of the Colville Tribes Okanogan Basin Monitoring and Evaluation Program (OBMEP) which began in 2004. Trapping for outmigrating fish began on 14 March 2006 and continued through 11 July 2006. Anadromous forms of Oncorhynchus, including summer steelhead (O. mykiss), Chinook (O. tshawytscha), and sockeye (O. nerka), were targeted for this study; all have verified, natural production in the Okanogan basin. Both 8-ft and 5-ft rotary screw traps were deployed on the Okanogan River from the Highway 20 Bridge and typically fished during evening hours or 24 hours per day, depending upon trap position and discharge conditions. Juvenile Chinook salmon were the most abundant species trapped in 2006 (10,682 fry and 2,024 smolts), followed by sockeye (205 parr and 3,291 smolts) and steelhead (1 fry and 333 smolts). Of the trapped Chinook, all fry were wild origin and all but five of the smolts were hatchery-reared. All trapped sockeye were wild origin and 88% of the steelhead smolts were hatchery-reared. Mark-recapture experiments were conducted using Chinook fry and hatchery-reared steelhead smolts (sockeye were not used in 2006 because the peak of the juvenile migration occurred prior to the onset of the mark-recapture experiments). A total of 930 chinook fry were marked and released across eight separate release dates (numbers of marked Chinook fry released per day ranged from 34 to 290 fish). A total of 11 chinook fry were recaptured for an overall trap efficiency of 1.18%. A total of 710 hatchery-reared steelhead were marked and released across three separate release dates (numbers of steelhead released per day ranged from 100 to 500 fish). A total of 12 steelhead were recaptured for an overall trap efficiency of 1.69%. A pooled Peterson estimator with a Chapman modification was used to produce population estimates for wild Chinook fry and hatchery-reared steelhead based on the results of the mark-recapture experiments. The 2006 populations for Chinook and steelhead were estimated to be 381,554 (95% confidence intervals: 175,731-587,377) and 14,164 (6,999-21,330), respectively. The population estimates were based on the periods in which mark-recapture experiments were initialized through the end of the trapping season (10 May for steelhead and 1 June for Chinook).

  6. Quantum Energy Teleportation with Trapped Ions

    E-Print Network [OSTI]

    Hotta, Masahiro

    2009-01-01T23:59:59.000Z

    We analyze a protocol of quantum energy teleportation that transports energy from the left edge of a linear ion crystal to the right edge by local operations and classical communication at a speed much higher than the speed of the phonon in the crystal. A probe qubit is strongly coupled with the phonon fluctuation in the ground state during short time and is projectively measured in order to get information about this phonon fluctuation. During the measurement process, phonons are excited by the time-dependent measurement interaction and energy of the excited phonons must be infused from outside the system. The obtained information is announced to the right edge of the crystal through a classical channel. Even though the phonons excited at the left edge do not arrive at the right edge yet when the information arrives at the right edge, we are able to soon extract energy from the ion at the right edge by using the announced information. Because the intermediate ions of the crystal are not excited during the ex...

  7. Trapping and hysteresis in two-phase flow in porous media: A pore-network study

    E-Print Network [OSTI]

    Wildenschild, Dorthe

    of hydrocarbon, and carbon sequestration problems where trap- ping of CO2 leads to safe underground storage. [4

  8. Ring of BEC pools as a trap for persistent flow

    SciTech Connect (OSTI)

    Dziarmaga, Jacek; Tylutki, Marek [Instytut Fizyki Uniwersytetu Jagiellonskiego, ul. Reymonta 4, PL-30-059 Krakow (Poland); Zurek, Wojciech H. [Theory Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2011-09-01T23:59:59.000Z

    Mott insulator-superfluid transition in a periodic lattice of Josephson junctions can be driven by tunneling rate increase. The resulting winding numbers W of the condensate wave function decrease with increasing quench time in accord with the Kibble-Zurek mechanism (KZM). However, in very slow quenches, Bose-Hubbard dynamics rearranges the wave-function phase so that its random walk cools, W{sup 2} decreases and eventually the wave function becomes too cold to overcome potential barriers separating different W. Thus, in contrast with KZM, in very slow quenches W{sup 2} is set by random walk with ''critical'' step size, independently of {tau}{sub Q}. As our study requires use of the truncated Wigner approximation (TWA) over relatively long time intervals, we investigate the validity of TWA by comparing its predictions with exact calculations for suitably small quantum systems.

  9. Light trapping for emission from a photovoltaic cell under normally incident monochromatic illumination

    SciTech Connect (OSTI)

    Takeda, Yasuhiko, E-mail: takeda@mosk.tytlabs.co.jp; Iizuka, Hideo; Mizuno, Shintaro; Hasegawa, Kazuo; Ichikawa, Tadashi; Ito, Hiroshi; Kajino, Tsutomu [Toyota Central Research and Development Laboratories, Inc., 41-1, Yokomichi, Nagakute, Aichi 480-1192 (Japan); Ichiki, Akihisa; Motohiro, Tomoyoshi [Green Mobility Collaborative Research Center, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601 (Japan)

    2014-09-28T23:59:59.000Z

    We have theoretically demonstrated a new light-trapping mechanism to reduce emission from a photovoltaic (PV) cell used for a monochromatic light source, which improves limiting conversion efficiency determined by the detailed balance. A multilayered bandpass filter formed on the surface of a PV cell has been found to prevent the light generated inside by radiative recombination from escaping the cell, resulting in a remarkable decrease of the effective solid angle for the emission. We have clarified a guide to design a suitable configuration of the bandpass filter and achieved significant reduction of the emission. The resultant gain in monochromatic conversion efficiency in the radiative limit due to the optimally designed 18-layerd bandpass filters is as high as 6% under normally incident 1064?nm illumination of 10 mW/cm{sup 2?}??1?kW/cm{sup 2}, compared with the efficiency for the perfect anti-reflection treatment to the surface of a conventional solar cell.

  10. FLUCTUATION IN TRAP-NET CATCHES IN THE UPPER MISSISSIPPI RIVER

    E-Print Network [OSTI]

    FLUCTUATION IN TRAP-NET CATCHES IN THE UPPER MISSISSIPPI RIVER if; Marine Biological LabofdiuryKay, Secretary Fish and Wildlife Service, Albert M. Day, Director FLUCTUATION IN TRAP NET CATCHES IN THE UPPER Gear used 3 Methods 5 Statistical considerations 5 Season trends in catch of trap nets 6 Black crappie

  11. Farmer on a farm in the Moamba district. the jatropha trap?

    E-Print Network [OSTI]

    Farmer on a farm in the Moamba district. the jatropha trap? the realities of farming jatropha in mozambique may 2010 | issue 118 © dino ribeiro agrofuels #12;the jatropha trap? the realities of farming jatropha in mozambique may 2010 | issue 118 the jatropha trap the realities of farming jatropha

  12. Solar Cell Light Trapping beyond the Ray Optic Limit Dennis M. Callahan,* Jeremy N. Munday,

    E-Print Network [OSTI]

    Atwater, Harry

    Solar Cell Light Trapping beyond the Ray Optic Limit Dennis M. Callahan,* Jeremy N. Munday: Photovoltaic cell, solar cell, local density of optical states (LDOS), light trapping, plasmonic, nanophotonic light trapping, as the solar cell absorber layer thickness is reduced, absorption is also reduced

  13. Angular constraint on light-trapping absorption enhancement in solar cells and Shanhui Fan

    E-Print Network [OSTI]

    Fan, Shanhui

    Angular constraint on light-trapping absorption enhancement in solar cells Zongfu Yua and Shanhui 2010; accepted 5 December 2010; published online 4 January 2011 Light trapping for solar cells can to both random tex- tured and periodic absorbers. To model light trapping in solar cells, we consider

  14. Note and Record A note on polyvinyl chloride (PVC) pipe traps for

    E-Print Network [OSTI]

    Pretoria, University of

    Note and Record A note on polyvinyl chloride (PVC) pipe traps for sampling vegetation of traditional traps, and many are furtive (Myers et al., 2007; Pittman et al., 2008). PVC pipe traps, which and Hyperolius (see Channing, 2001; du Preez & Carruthers, 2009), may be attracted to artificial refugia of PVC

  15. The Impact of Simple Institutions in Experimental Economies with Poverty Traps

    E-Print Network [OSTI]

    Greer, Julia R.

    The Impact of Simple Institutions in Experimental Economies with Poverty Traps C. Mónica Capra a threshold. The threshold externality generates two equilibria--a suboptimal "poverty trap" and an optimal typically sink into the poverty trap and the optimal equilibrium is never reached. However, the ability

  16. Efficient Dynamic Contracts: Enabling A Poor borrower To Get Out of Poverty Trap

    E-Print Network [OSTI]

    Bandyopadhyay, Antar

    Efficient Dynamic Contracts: Enabling A Poor borrower To Get Out of Poverty Trap Dyotona Dasgupta, New Delhi 110016, India Keywords: Dynamic Contracts, Progressive Lending, Collateral, Poverty Trap exists which enables a poor borrower to get out of poverty trap. Though progressive lending is a common

  17. With Exhaustible Resources, Can A Developing Country Escape From The Poverty Trap?

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    With Exhaustible Resources, Can A Developing Country Escape From The Poverty Trap? Cuong Le Van is convex-concave, so that the economy may be locked into a poverty trap. We show that the extent to which the country will escape from the poverty trap depends, besides the interactions between its technology and its

  18. Simulation of diffusion and trapping in digitized heterogeneous media David A. Coke@ and Salvatore Torquatob)

    E-Print Network [OSTI]

    Torquato, Salvatore

    Simulation of diffusion and trapping in digitized heterogeneous media David A. Coke@ and Salvatore of a Brownian particle diffusing among a, digitized lattice-based domain of traps. Following the first, the inverse of the trapping rate, is obtained for a variety of configurations involving digitized spheres

  19. An all-glass microfluidic cell for the ABEL trap: fabrication and Adam E. Cohen

    E-Print Network [OSTI]

    Shapiro, Benjamin

    An all-glass microfluidic cell for the ABEL trap: fabrication and modeling Adam E. Cohen Department trap is a microfluidic cell. In previous incarnations of the ABEL trap, the microfluidic cell microfluidic cell, made entirely out of glass. This new design significantly decreases the rate

  20. Mechanisms for Fluorescence Blinking and Charge Carrier Trapping in Single Semiconductor Nanocrystals

    E-Print Network [OSTI]

    Cordones, Amy Ashbrook

    2012-01-01T23:59:59.000Z

    photovoltaics and higher radiative recombination efficienciesfor example, in photovoltaics) or the high efficiency ofefficiencies much lower than is theorized for nanocrystal-based photovoltaics,

  1. Thermal Deactivation Mechanisms of Fully-Formed Lean NOx Trap Catalysts

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion |Energy Usage »of EnergyThe EnergyDepartment of Energy TheAged by Lean/Rich Cycling |

  2. Investigation of Aging Mechanisms in Lean NOx Traps | Department of Energy

    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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarly Career Scientists'Montana.ProgramJulietipDepartmentJune 20,AmongDevelopmentJuly 12, 2007

  3. Investigation of Aging Mechanisms in Lean NOx Traps | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeatMulti-Dimensionalthe10 DOE VehicleStationary FuelPresentation from the U.S. DOE2009

  4. Features of conduction mechanisms in Si/oligo-{beta}-naphthol/metal heterostructures

    SciTech Connect (OSTI)

    Hasannli, Sh. M., E-mail: Hasanli_sh@rambler.ru; Mursakulov, N. N.; Samedova, U. F.; Abdulzade, N. N.; Mamedov, B. A. [National Academy of Sciences of Azerbaijan, Institute of Physics (Azerbaijan); Guseynov, R. K. [Ganja State University (Azerbaijan)

    2010-07-15T23:59:59.000Z

    Conduction mechanisms in Si-polymer-metal heterostructures with oligo-{beta}-naphthol as a wide band-gap polymer have been studied. The results obtained are explained within the models of hopping transport via trap levels, Schottky emission, and field tunneling emission. Different charge transport mechanisms operate in different temperature ranges and under different electric fields.

  5. Electronic quantum effects mapped onto non-Born-Oppenheimer nuclear paths: Nonclassical surmounting over potential barriers and trapping above the transition states due to nonadiabatic path-branching

    SciTech Connect (OSTI)

    Yamamoto, Kentaro, E-mail: kyamamoto@mns2.c.u-tokyo.ac.jp; Takatsuka, Kazuo, E-mail: kaztak@mns2.c.u-tokyo.ac.jp [Department of Basic Science, The University of Tokyo, Komaba, 153-8902 Tokyo (Japan)] [Department of Basic Science, The University of Tokyo, Komaba, 153-8902 Tokyo (Japan)

    2014-03-28T23:59:59.000Z

    We develop the path-branching representation for nonadiabatic electron wavepacket dynamics [T. Yonehara and K. Takatsuka, J. Chem. Phys. 132, 244102 (2010)] so as to treat dynamics in an energy range comparable to the barrier height of adiabatic potential energy curves. With this representation two characteristic chemical reaction dynamics are studied, in which an incident nuclear wavepacket encounters a potential barrier, on top of which lies another nonadiabatically coupled adiabatic potential curve: (1) Dynamics of initial paths coming into the nonadiabatic interaction region with energy lower than the barrier height. They branch into two pieces (and repeat branching subsequently), the upper counterparts of which can penetrate into a classically inaccessible high energy region and eventually branch back to the product region on the ground state curve. This is so to say surmounting the potential barrier via nonadiabatically coupled excited state, and phenomenologically looks like the so-called deep tunneling. (2) Dynamics of classical paths whose initial energies are a little higher than the barrier but may be lower than the bottom of the excited state. They can undergo branching and some of those components are trapped on top of the potential barrier, being followed by the population decay down to the lower state flowing both to product and reactant sites. Such expectations arising from the path-branching representation are numerically confirmed with full quantum mechanical wavepacket dynamics. This phenomenon may be experimentally observed as time-delayed pulses of wavepacket trains.

  6. Mechanical memory

    DOE Patents [OSTI]

    Gilkey, Jeffrey C. (Albuquerque, NM); Duesterhaus, Michelle A. (Albuquerque, NM); Peter, Frank J. (Albuquerque, NM); Renn, Rosemarie A. (Albuquerque, NM); Baker, Michael S. (Albuquerque, NM)

    2006-05-16T23:59:59.000Z

    A first-in-first-out (FIFO) microelectromechanical memory apparatus (also termed a mechanical memory) is disclosed. The mechanical memory utilizes a plurality of memory cells, with each memory cell having a beam which can be bowed in either of two directions of curvature to indicate two different logic states for that memory cell. The memory cells can be arranged around a wheel which operates as a clocking actuator to serially shift data from one memory cell to the next. The mechanical memory can be formed using conventional surface micromachining, and can be formed as either a nonvolatile memory or as a volatile memory.

  7. Mechanical memory

    DOE Patents [OSTI]

    Gilkey, Jeffrey C. (Albuquerque, NM); Duesterhaus, Michelle A. (Albuquerque, NM); Peter, Frank J. (Albuquerque, NM); Renn, Rosemarie A. (Alburquerque, NM); Baker, Michael S. (Albuquerque, NM)

    2006-08-15T23:59:59.000Z

    A first-in-first-out (FIFO) microelectromechanical memory apparatus (also termed a mechanical memory) is disclosed. The mechanical memory utilizes a plurality of memory cells, with each memory cell having a beam which can be bowed in either of two directions of curvature to indicate two different logic states for that memory cell. The memory cells can be arranged around a wheel which operates as a clocking actuator to serially shift data from one memory cell to the next. The mechanical memory can be formed using conventional surface micromachining, and can be formed as either a nonvolatile memory or as a volatile memory.

  8. A comb-sampling method for enhanced mass analysis in linear electrostatic ion traps

    SciTech Connect (OSTI)

    Greenwood, J. B.; Kelly, O.; Calvert, C. R.; Duffy, M. J.; King, R. B.; Belshaw, L.; Graham, L.; Alexander, J. D.; Williams, I. D. [Centre for Plasma Physics, School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN (United Kingdom); Bryan, W. A. [Department of Physics, Swansea University, Swansea SA2 8PP (United Kingdom); Turcu, I. C. E.; Cacho, C. M.; Springate, E. [Central Laser Facility, STFC Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0QX (United Kingdom)

    2011-04-15T23:59:59.000Z

    In this paper an algorithm for extracting spectral information from signals containing a series of narrow periodic impulses is presented. Such signals can typically be acquired by pickup detectors from the image-charge of ion bunches oscillating in a linear electrostatic ion trap, where frequency analysis provides a scheme for high-resolution mass spectrometry. To provide an improved technique for such frequency analysis, we introduce the CHIMERA algorithm (Comb-sampling for High-resolution IMpulse-train frequency ExtRAaction). This algorithm utilizes a comb function to generate frequency coefficients, rather than using sinusoids via a Fourier transform, since the comb provides a superior match to the data. This new technique is developed theoretically, applied to synthetic data, and then used to perform high resolution mass spectrometry on real data from an ion trap. If the ions are generated at a localized point in time and space, and the data is simultaneously acquired with multiple pickup rings, the method is shown to be a significant improvement on Fourier analysis. The mass spectra generated typically have an order of magnitude higher resolution compared with that obtained from fundamental Fourier frequencies, and are absent of large contributions from harmonic frequency components.

  9. Measurement of the beta-neutrino correlation in laser trapped {sup 21}Na

    SciTech Connect (OSTI)

    Scielzo, Nicholas David

    2003-06-01T23:59:59.000Z

    Trapped radioactive atoms are an appealing source for precise measurements of the beta-neutrino correlation coefficient, a, since the momentum of the neutrino can be inferred from the detection of the unperturbed low-energy recoil daughter nucleus. Sodium-21 is produced on-line at the 88'' cyclotron at Lawrence Berkeley National Laboratory, and 8e5 atoms have been maintained in a magneto-optical trap. A static electric field draws daughter Neon-21 ions to a microchannel plate detector and betas are detected in coincidence with a plastic scintillator beta detector. The Neon-21 time-of-flight distribution determines the beta neutrino correlation coefficient, a. The resulting charge-state distribution is compared to a simple model based on the sudden approximation which suggests a small but important contribution from nuclear recoil-induced ionization. A larger than expected fraction of the daughters are detected in positive charge-states, but no dependence on either the beta or recoil nucleus energy was observed. We find a = 0.5243 plus or minus 0.0092, which is in 3.6 sigma disagreement with the Standard Model prediction of a = 0.559 plus or minus 0.003. Aside from a deviation from the Standard Model, a possible explanation for the discrepancy is that the branching ratio to the first excited state is in error.

  10. Electromagnetic two-dimensional analysis of trapped-ion eigenmodes

    SciTech Connect (OSTI)

    Kim, D.; Rewoldt, G.

    1984-11-01T23:59:59.000Z

    A two-dimensional electromagnetic analysis of the trapped-ion instability for the tokamak case with ..beta.. not equal to 0 has been made, based on previous work in the electrostatic limit. The quasineutrality condition and the component of Ampere's law along the equilibrium magnetic field are solved for the perturbed electrostatic potential and the component of the perturbed vector potential along the equilibrium magnetic field. The general integro-differential equations are converted into a matrix eigenvalue-eigenfunction problem by expanding in cubic B-spline finite elements in the minor radius and in Fourier harmonics in the poloidal angle. A model MHD equilibrium with circular, concentric magnetic surfaces and large aspect ratio is used which is consistent with our assemption that B << 1. The effect on the trapped-ion mode of including these electromagnetic extensions to the calculation is considered, and the temperature (and ..beta..) scaling of the mode frequency is shown and discussed.

  11. Photoionization of strontium for trapped-ion quantum information processing

    E-Print Network [OSTI]

    K. Vant; J. Chiaverini; W. Lybarger; D. J. Berkeland

    2006-07-07T23:59:59.000Z

    We report a demonstration of simple and effective loading of strontium ions into a linear radio frequency Paul trap using photoionization. The ionization pathway is 5s2 1S0 -- 5s5p 1P1 -- 5p2 1D2, and the 5p2 1D2 final state is auto-ionizing. Both transitions are driven using diode lasers: a grating-stabilized 922 nm diode doubled in a single pass through potassium niobate to 461 nm and a bare diode at 405 nm. Using this technique, we have reduced the background pressure during the ion loading process by a factor of 2 compared to the conventional technique of electron bombardment. Initial ion temperatures are low enough that the ions immediately form crystals. It is also possible to observe the trapping region with a CCD camera during ion creation, allowing specific ion number loading with high probability.

  12. A bosonic Josephson junction controlled by a single trapped ion

    E-Print Network [OSTI]

    R. Gerritsma; A. Negretti; H. Doerk; Z. Idziaszek; T. Calarco; F. Schmidt-Kaler

    2012-07-25T23:59:59.000Z

    We theoretically investigate the properties of a double-well bosonic Josephson junction coupled to a single trapped ion. We find that the coupling between the wells can be controlled by the internal state of the ion, which can be used for studying mesoscopic entanglement between the two systems and to measure their interaction with high precision. As a particular example we consider a single $^{87}$Rb atom and a small Bose-Einstein condensate controlled by a single $^{171}$Yb$^+$ ion. We calculate inter-well coupling rates reaching hundreds of Hz, while the state dependence amounts to tens of Hz for plausible values of the currently unknown s-wave scattering length between the atom and the ion. The analysis shows that it is possible to induce either the self-trapping or the tunneling regime, depending on the internal state of the ion. This enables the generation of large scale ion-atomic wavepacket entanglement within current technology.

  13. Inertial particle trapping in an open vortical flow

    E-Print Network [OSTI]

    Jean-Regis Angilella; Rafael D. Vilela; Adilson E. Motter

    2014-03-28T23:59:59.000Z

    Recent numerical results on advection dynamics have shown that particles denser than the fluid can remain trapped indefinitely in a bounded region of an open fluid flow. Here, we investigate this counterintuitive phenomenon both numerically and analytically to establish the conditions under which the underlying particle-trapping attractors can form. We focus on a two-dimensional open flow composed of a pair of vortices and its specular image, which is a system we represent as a vortex pair plus a wall along the symmetry line. Considering particles that are much denser than the fluid, we show that two point attractors form in the neighborhood of the vortex pair provided that the particle Stokes number is smaller than a critical value of order unity. In the absence of the wall, the boundaries of the basins of the attracting points are smooth. When the wall is present, the point attractors describe counter-rotating ellipses in this frame, with a period equal to half the period of one isolated vortex pair. However, their boundaries are shown to become fractal if the distance to the wall is smaller than a critical distance that scales with the inverse square root of the Stokes number. This transformation is related to the breakdown of a separatrix that gives rise to a heteroclinic tangle close to the vortices, which we describe using a Melnikov function. For an even smaller distance to the wall, we demonstrate that a second separatrix breaks down and a new heteroclinic tangle forms farther away from the vortices. Particles released in the open part of the flow can approach the attractors and be trapped permanently provided that they cross the two separatrices. Furthermore, the trapping of heavy particles from the open flow is shown to be robust to the presence of gravity, viscosity, and noise.

  14. Adiabatic trapping in coupled kinetic Alfven-acoustic waves

    SciTech Connect (OSTI)

    Shah, H. A.; Ali, Z. [Department of Physics, G.C. University, 54000 Lahore (Pakistan); Masood, W. [COMSATS, Institute of Information Technology, Park Road, Chak Shahzad, Islamabad 44000 (Pakistan); National Centre for Physics (NCP), Shahdara Valley Road, 44000 Islamabad (Pakistan); Theoretical Plasma Physics Division, P. O. Nilore, Islamabad (Pakistan)

    2013-03-15T23:59:59.000Z

    In the present work, we have discussed the effects of adiabatic trapping of electrons on obliquely propagating Alfven waves in a low {beta} plasma. Using the two potential theory and employing the Sagdeev potential approach, we have investigated the existence of arbitrary amplitude coupled kinetic Alfven-acoustic solitary waves in both the sub and super Alfvenic cases. The results obtained have been analyzed and presented graphically and can be applied to regions of space where the low {beta} assumption holds true.

  15. Fabrication and heating rate study of microscopic surface electrode ion traps

    E-Print Network [OSTI]

    N. Daniilidis; S. Narayanan; S. A. Möller; R. Clark; T. E. Lee; P. J. Leek; A. Wallraff; St. Schulz; F. Schmidt-Kaler; H. Häffner

    2010-09-15T23:59:59.000Z

    We report heating rate measurements in a microfabricated gold-on-sapphire surface electrode ion trap with trapping height of approximately 240 micron. Using the Doppler recooling method, we characterize the trap heating rates over an extended region of the trap. The noise spectral density of the trap falls in the range of noise spectra reported in ion traps at room temperature. We find that during the first months of operation the heating rates increase by approximately one order of magnitude. The increase in heating rates is largest in the ion loading region of the trap, providing a strong hint that surface contamination plays a major role for excessive heating rates. We discuss data found in the literature and possible relation of anomalous heating to sources of noise and dissipation in other systems, namely impurity atoms adsorbed on metal surfaces and amorphous dielectrics.

  16. Single microbe trap and release in sub-microfluidics

    SciTech Connect (OSTI)

    Vasdekis, Andreas E.

    2013-05-08T23:59:59.000Z

    Lab-on-a-chip systems have substantially impacted the way life-sciences are explored; life on earth, however, comprises mostly of microbes, which due to their sub-micron dimensions and high mobility are more challenging to dynamically manipulate on-a-chip. To address this challenge, we developed a high resolution microfluidic system (submicrofluidics) fabricated by direct electron beam lithography that is capable of trapping single microbes and releasing them upon demand. The fabrication method enabled the integration of sub-micron indentations (400 nm) with millimetre-scale fluidic channels rapidly in a single processing step. The larger channels deliver the cell suspension and reagents, while the sub-micron indentations immobilize the cells by locally increasing the hydrodynamic resistance. By volume exclusion, single cell trapping was possible in this system without any surface treatment. By increasing the flow rate, the microbes overcome the trap barrier and pass through the narrow indentation without undergoing lysis with kinetics that depend on their size. The fabrication method and its performance are described, along with microbial characterisations using E. coli.

  17. FORMATION OF PLANETARY CORES AT TYPE I MIGRATION TRAPS

    SciTech Connect (OSTI)

    Sandor, Zsolt; Dullemond, Cornelis P. [Max Planck Research Group, Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, 69117 Heidelberg (Germany); Lyra, Wladimir, E-mail: sandor@mpia.de [Department of Astrophysics, American Museum of Natural History, 79th Street at Central Park West, New York, NY 10024 (United States)

    2011-02-10T23:59:59.000Z

    One of the long-standing unsolved problems of planet formation is how solid bodies of a few decimeters in size can 'stick' to form large planetesimals. This is known as the 'meter-size barrier'. In recent years, it has become increasingly clear that some form of 'particle trapping' must have played a role in overcoming the meter-size barrier. Particles can be trapped in long-lived local pressure maxima, such as those in anticyclonic vortices, zonal flows, or those believed to occur near ice lines or at dead zone boundaries. Such pressure traps are the ideal sites for the formation of planetesimals and small planetary embryos. Moreover, they likely produce large quantities of such bodies in a small region, making it likely that subsequent N-body evolution may lead to even larger planetary embryos. The goal of this Letter is to show that this indeed happens, and to study how efficient it is. In particular, we wish to find out if rocky/icy bodies as large as 10 M{sub +} can form within 1 Myr, since such bodies are the precursors of gas giant planets in the core accretion scenario.

  18. Injection of CO2 with H2S and SO2 and Subsequent Mineral Trapping in Sandstone-Shale Formation

    SciTech Connect (OSTI)

    Xu, Tianfu; Apps, John A.; Pruess, Karsten; Yamamoto, Hajime

    2004-09-07T23:59:59.000Z

    Carbon dioxide (CO{sub 2}) injection into deep geologic formations can potentially reduce atmospheric emissions of greenhouse gases. Sequestering less-pure CO{sub 2} waste streams (containing H{sub 2}S and/or SO{sub 2}) would be less expensive or would require less energy than separating CO{sub 2} from flue gas or a coal gasification process. The long-term interaction of these injected acid gases with shale-confining layers of a sandstone injection zone has not been well investigated. We therefore have developed a conceptual model of injection of CO{sub 2} with H{sub 2}S and/or SO{sub 2} into a sandstone-shale sequence, using hydrogeologic properties and mineral compositions commonly encountered in Gulf Coast sediments of the United States. We have performed numerical simulations of a 1-D radial well region considering sandstone alone and a 2-D model using a sandstone-shale sequence under acid-gas injection conditions. Results indicate that shale plays a limited role in mineral alteration and sequestration of gases within a sandstone horizon for short time periods (10,000 years in present simulations). The co-injection of SO{sub 2} results in different pH distribution, mineral alteration patterns, and CO{sub 2} mineral sequestration than the co-injection of H{sub 2}S or injection of CO{sub 2} alone. Simulations generate a zonal distribution of mineral alteration and formation of carbon and sulfur trapping minerals that depends on the pH distribution. The co-injection of SO{sub 2} results in a larger and stronger acidified zone close to the well. Precipitation of carbon trapping minerals occurs within the higher pH regions beyond the acidified zones. In contrast, sulfur trapping minerals are stable at low pH ranges (below 5) within the front of the acidified zone. Corrosion and well abandonment due to the co-injection of SO{sub 2} could be important issues. Significant CO{sub 2} is sequestered in ankerite and dawsonite, and some in siderite. The CO{sub 2} mineral-trapping capability can reach 80 kg per cubic meter of medium. Most sulfur is trapped through alunite precipitation, although some is trapped by anhydrite precipitation and minor amount of pyrite. The addition of the acid gases and induced mineral alteration result in changes in porosity. The limited information currently available on the mineralogy of natural high-pressure acid-gas reservoirs is generally consistent with our simulations.

  19. Mechanical engineering Department Seminar

    E-Print Network [OSTI]

    Lin, Xi

    Mechanical engineering Department Seminar Eric Suuberg Professor Brown University Another Reason, chemicals of anthropogenic origin can migrate from soil into houses, invis- ibly, over time, impacting the soil gas migration problem, and used these to develop simple analytical approaches to estimating

  20. Computational mechanics

    SciTech Connect (OSTI)

    Goudreau, G.L.

    1993-03-01T23:59:59.000Z

    The Computational Mechanics thrust area sponsors research into the underlying solid, structural and fluid mechanics and heat transfer necessary for the development of state-of-the-art general purpose computational software. The scale of computational capability spans office workstations, departmental computer servers, and Cray-class supercomputers. The DYNA, NIKE, and TOPAZ codes have achieved world fame through our broad collaborators program, in addition to their strong support of on-going Lawrence Livermore National Laboratory (LLNL) programs. Several technology transfer initiatives have been based on these established codes, teaming LLNL analysts and researchers with counterparts in industry, extending code capability to specific industrial interests of casting, metalforming, and automobile crash dynamics. The next-generation solid/structural mechanics code, ParaDyn, is targeted toward massively parallel computers, which will extend performance from gigaflop to teraflop power. Our work for FY-92 is described in the following eight articles: (1) Solution Strategies: New Approaches for Strongly Nonlinear Quasistatic Problems Using DYNA3D; (2) Enhanced Enforcement of Mechanical Contact: The Method of Augmented Lagrangians; (3) ParaDyn: New Generation Solid/Structural Mechanics Codes for Massively Parallel Processors; (4) Composite Damage Modeling; (5) HYDRA: A Parallel/Vector Flow Solver for Three-Dimensional, Transient, Incompressible Viscous How; (6) Development and Testing of the TRIM3D Radiation Heat Transfer Code; (7) A Methodology for Calculating the Seismic Response of Critical Structures; and (8) Reinforced Concrete Damage Modeling.

  1. Combining Capillary Electrochromatography with Ion Trap Accumulation and Time-of-Flight Mass Spectrometry 

    E-Print Network [OSTI]

    Simpson, David C

    metre, an average chromatographic efficiency of 95,000 was obtained with a test mixture that consisted of acenaphthene, biphenyl, fluorene, naphthalene and phenanthrene. Furthermore, using the leak inlet, naphthalene was detected as a 100 nM solution...

  2. Real-Time Measurement of Diesel Trap Efficiency | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion | Department ofT ib l L dDepartment ofList? |EnergyDepartmentMilestone

  3. Consequences of three-dimensional physical and electromagnetic structures on dust particle trapping in high plasma density

    E-Print Network [OSTI]

    Kushner, Mark

    gradients are present, which introduce fluid drag and thermophoretic forces, dust particle traps may

  4. Long-time evolution of sequestered CO$_2$ in porous media

    E-Print Network [OSTI]

    Cohen, Yossi

    2014-01-01T23:59:59.000Z

    CO$_2$ sequestration in subsurface reservoirs is important for limiting atmospheric CO$_2$ concentrations. However, a complete physical picture able to predict the structure developing within the porous medium is lacking. We investigate theoretically reactive transport in the long-time evolution of carbon in the brine-rock environment. As CO$_2$ is injected into a brine-rock environment, a carbonate-rich region is created amid brine. Within the carbonate-rich region minerals dissolve and migrate from regions of high concentration to low concentration, along with other dissolved carbonate species. This causes mineral precipitation at the interface between the two regions. We argue that precipitation in a small layer reduces diffusivity, and eventually causes mechanical trapping of the CO$_2$. Consequently, only a small fraction of the CO$_2$ is converted to solid mineral; the remainder either dissolves in water or is trapped in its original form. We also study the case of a pure CO$_2$ bubble surrounded by bri...

  5. Matter: Space without Time

    E-Print Network [OSTI]

    Yousef Ghazi-Tabatabai

    2012-11-19T23:59:59.000Z

    While Quantum Gravity remains elusive and Quantum Field Theory retains the interpretational difficulties of Quantum Mechanics, we have introduced an alternate approach to the unification of particles, fields, space and time, suggesting that the concept of matter as space without time provides a framework which unifies matter with spacetime and in which we anticipate the development of complete theories (ideally a single unified theory) describing observed 'particles, charges, fields and forces' solely with the geometry of our matter-space-time universe.

  6. 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.

  7. Ground-state cooling of a trapped ion using long-wavelength radiation

    E-Print Network [OSTI]

    Weidt, S; Webster, S C; Standing, E D; Rodriguez, A; Webb, A E; Lekitsch, B; Hensinger, W K

    2015-01-01T23:59:59.000Z

    We demonstrate ground-state cooling of a trapped ion using long-wavelength radiation. This is a powerful tool for the implementation of quantum operations, where long-wavelength radiation instead of lasers is used for motional quantum state engineering. We measure a mean phonon number of $\\overline{n} = 0.13(4)$ after sideband cooling, corresponding to a ground-state occupation probability of 88(7)\\%. After preparing in the vibrational Fock state $\\left|n=0\\right\\rangle$, we implement sideband Rabi oscillations which last for more than 10 ms, demonstrating the long coherence time of our system. We also use the ability to ground-state cool to accurately measure the motional heating rate and report a reduction by almost two orders of magnitude compared to our previously measured result, which we attribute to carefully eliminating sources of electrical noise in the system.

  8. Ground-state cooling of a trapped ion using long-wavelength radiation

    E-Print Network [OSTI]

    S. Weidt; J. Randall; S. C. Webster; E. D. Standing; A. Rodriguez; A. E. Webb; B. Lekitsch; W. K. Hensinger

    2015-01-07T23:59:59.000Z

    We demonstrate ground-state cooling of a trapped ion using long-wavelength radiation. This is a powerful tool for the implementation of quantum operations, where long-wavelength radiation instead of lasers is used for motional quantum state engineering. We measure a mean phonon number of $\\overline{n} = 0.13(4)$ after sideband cooling, corresponding to a ground-state occupation probability of 88(7)\\%. After preparing in the vibrational Fock state $\\left|n=0\\right\\rangle$, we implement sideband Rabi oscillations which last for more than 10 ms, demonstrating the long coherence time of our system. We also use the ability to ground-state cool to accurately measure the motional heating rate and report a reduction by almost two orders of magnitude compared to our previously measured result, which we attribute to carefully eliminating sources of electrical noise in the system.

  9. Precision lifetime measurements of a single trapped ion with ultrafast laser pulses

    E-Print Network [OSTI]

    D. L. Moehring; B. B. Blinov; D. W. Gidley; R. N. Kohn Jr.; M. J. Madsen; T. D. Sanderson; R. S. Vallery; C. Monroe

    2005-05-15T23:59:59.000Z

    We report precision measurements of the excited state lifetime of the $5p$ $^2P_{1/2}$ and $5p$ $^2P_{3/2}$ levels of a single trapped Cd$^+$ ion. The ion is excited with picosecond laser pulses from a mode-locked laser and the distribution of arrival times of spontaneously emitted photons is recorded. The resulting lifetimes are 3.148 $\\pm$ 0.011 ns and 2.647 $\\pm$ 0.010 ns for $^2P_{1/2}$ and $^2P_{3/2}$ respectively. With a total uncertainty of under 0.4%, these are among the most precise measurements of any atomic state lifetimes to date.

  10. Formation of molecular ions by radiative association of cold trapped atoms and ions

    E-Print Network [OSTI]

    Humberto Da Silva Jr; Maurice Raoult; Mireille Aymar; Olivier Dulieu

    2015-01-26T23:59:59.000Z

    Radiative emission during cold collisions between trapped laser-cooled Rb atoms and alkaline-earth ions (Ca + , Sr + , Ba +) and Yb + are studied theoretically, using accurate effective-core-potential based quantum chemistry calculations of potential energy curves and transition dipole moments of the related molecular ions. Radiative association of molecular ions is predicted to occur for all systems with a cross section two to ten times larger than the radiative charge transfer one. Partial and total rate constants are also calculated and compared to available experiments. Narrow shape resonances are expected, which could be detectable at low temperature with an experimental resolution at the limit of the present standards. Vibrational distributions are also calculated, showing that the final molecular ions are not created in their ground state level.

  11. Formation of molecular ions by radiative association of cold trapped atoms and ions

    E-Print Network [OSTI]

    Silva, Humberto Da; Aymar, Mireille; Dulieu, Olivier

    2015-01-01T23:59:59.000Z

    Radiative emission during cold collisions between trapped laser-cooled Rb atoms and alkaline-earth ions (Ca + , Sr + , Ba +) and Yb + are studied theoretically, using accurate effective-core-potential based quantum chemistry calculations of potential energy curves and transition dipole moments of the related molecular ions. Radiative association of molecular ions is predicted to occur for all systems with a cross section two to ten times larger than the radiative charge transfer one. Partial and total rate constants are also calculated and compared to available experiments. Narrow shape resonances are expected, which could be detectable at low temperature with an experimental resolution at the limit of the present standards. Vibrational distributions are also calculated, showing that the final molecular ions are not created in their ground state level.

  12. Parametric self pulsing in a quantum opto-mechanical system

    E-Print Network [OSTI]

    Holmes, C A

    2009-01-01T23:59:59.000Z

    We describe an opto-mechanical system in which the coupling between optical and mechanical degrees of freedom takes the form of a fully quantised third-order parametric interaction. Two physical realisations are proposed: a harmonically trapped atom in a standing wave and the `membrane in the middle' model. The dominant resonant interaction corresponds to a stimulated Raman process in which two phonons are converted into a single cavity photon. We show that this system can exhibit a stable limit cycle in which energy is periodically exchanged between optical and mechanical degrees of freedom. This is equivalently described as a parametric self-pulsing.

  13. Mass fluctuations and diffusion in time-dependent random environments

    E-Print Network [OSTI]

    Giorgio Krstulovic; Rehab Bitane; Jeremie Bec

    2012-03-27T23:59:59.000Z

    A mass ejection model in a time-dependent random environment with both temporal and spatial correlations is introduced. When the environment has a finite correlation length, individual particle trajectories are found to diffuse at large times with a displacement distribution that approaches a Gaussian. The collective dynamics of diffusing particles reaches a statistically stationary state, which is characterized in terms of a fluctuating mass density field. The probability distribution of density is studied numerically for both smooth and non-smooth scale-invariant random environments. A competition between trapping in the regions where the ejection rate of the environment vanishes and mixing due to its temporal dependence leads to large fluctuations of mass. These mechanisms are found to result in the presence of intermediate power-law tails in the probability distribution of the mass density. For spatially differentiable environments, the exponent of the right tail is shown to be universal and equal to -3/2. However, at small values, it is found to depend on the environment. Finally, spatial scaling properties of the mass distribution are investigated. The distribution of the coarse-grained density is shown to posses some rescaling properties that depend on the scale, the amplitude of the ejection rate, and the H\\"older exponent of the environment.

  14. Effect of Trapped Energetic Particles on the Resistive Wall Mode

    SciTech Connect (OSTI)

    Hao, G. Z.; Wang, A. K.; Qiu, X. M. [Southwestern Institute of Physics, Post Office Box 432, Chengdu 610041 (China); Liu, Y. Q. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom)

    2011-07-01T23:59:59.000Z

    A stability analysis for the resistive wall mode is studied in the presence of trapped energetic particles (EPs). When the EPs' beta exceeds a critical value, a fishbonelike bursting mode (FLM) with an external kink eigenstructure can exist. This offers the first analytic interpretation of the experimental observations [Phys. Rev. Lett. 103, 045001 (2009)]. The mode-particle resonances for the FLM and the q=1 fishbone occur in different regimes of the precession frequency of EPs. In certain ranges of the plasma rotation speed and the EPs' beta, a mode conversion can occur between the resistive wall mode and FLM.

  15. Simulation of dust streaming in toroidal traps: Stationary flows

    SciTech Connect (OSTI)

    Reichstein, Torben; Piel, Alexander [IEAP, Christian-Albrechts-Universitaet, D-24098 Kiel (Germany)

    2011-08-15T23:59:59.000Z

    Molecular-dynamic simulations were performed to study dust motion in a toroidal trap under the influence of the ion drag force driven by a Hall motion of the ions in E x B direction, gravity, inter-particle forces, and friction with the neutral gas. This article is focused on the inhomogeneous stationary streaming motion. Depending on the strength of friction, the spontaneous formation of a stationary shock or a spatial bifurcation into a fast flow and a slow vortex flow is observed. In the quiescent streaming region, the particle flow features a shell structure which undergoes a structural phase transition along the flow direction.

  16. Wolf Trap, Virginia: Energy Resources | 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 on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia:FAQ < RAPID Jump to:SeadovCooperative JumpWilliamson County,Bay,°Trap, Virginia: Energy Resources Jump to:

  17. Single microbe trap and release in sub-microfluidics. | EMSL

    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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administrationcontroller systemsBi (2)Sharing Smart GridShiftMethodSimwYpes(tm)Single microbe trap

  18. Stabilization of the resistive wall mode instability by trapped energetic particles

    SciTech Connect (OSTI)

    Hao, G. Z.; Wang, A. K.; Jiang, H. B.; Lu, Gaimin; He, H. D.; Qiu, X. M. [Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041 (China); Liu, Y. Q. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom)

    2011-03-15T23:59:59.000Z

    A theoretical model for investigating the effect of the trapped energetic particles (EPs) on the resistive wall mode (RWM) instability is proposed. The results demonstrate that the trapped EPs have a dramatic stabilizing effect on the RWM because of resonant interaction between the mode and the magnetic precession drift motion of the trapped EPs. The results also show that the effect of the trapped EPs depends on the wall position. In addition, the stabilizing effect becomes stronger when the plasma rotation is taken into account. For sufficiently fast plasma rotation, the trapped EPs can lead to the complete stabilization of the RWM. Furthermore, the trapped EPs can induce a finite real frequency of the RWM in the absence of plasma rotation.

  19. Conformal mechanics

    SciTech Connect (OSTI)

    Gonera, Joanna, E-mail: jgonera@uni.lodz.pl

    2013-08-15T23:59:59.000Z

    The SL(2,R) invariant Hamiltonian systems are discussed within the framework of the orbit method. It is shown that both the dynamics and the symmetry transformations are globally well-defined on phase space. The flexibility in the choice of the time variable and the Hamiltonian function described in the paper by de Alfaro et al. [Nuovo Cimento 34A (1976) 569] is related to the nontrivial global structure of 1+0-dimensional space–time. The operational definition of time is discussed.

  20. Agreement Mechanisms

    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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc Documentation RUCProductstwrmrAre theAdministratorCFM LEAPAgenda AgendaAgreement Mechanisms

  1. Angular constraint on light-trapping absorption enhancement in solar cells

    E-Print Network [OSTI]

    Yu, Zongfu

    2010-01-01T23:59:59.000Z

    Light trapping for solar cells can reduce production cost and improve energy conversion efficiency. Understanding some of the basic theoretical constraints on light trapping is therefore of fundamental importance. Here, we develop a general angular constraint on the absorption enhancement in light trapping. We show that there is an upper limit for the angular integration of absorption enhancement factors. This limit is determined by the number of accessible resonances supported by an absorber.

  2. Light trapping and near-unity solar absorption in a three-dimensional photonic-crystal

    E-Print Network [OSTI]

    John, Sajeev

    Light trapping and near-unity solar absorption in a three-dimensional photonic-crystal Ping Kuang,1 opens up a new door for light trapping and near-unity solar absorption over broad s and wide angles://dx.doi.org/10.1364/OL.38.004200 There is a great deal of interest in efficient light trapping in thin film solar

  3. Measuring molecular electric dipoles using trapped atomic ions and ultrafast laser pulses

    E-Print Network [OSTI]

    Jordi Mur-Petit; Juan José García-Ripoll

    2015-01-12T23:59:59.000Z

    We study a hybrid quantum system composed of an ion and an electric dipole. We show how a trapped ion can be used to measure the small electric field generated by a classical dipole. We discuss the application of this scheme to measure the electric dipole moment of cold polar molecules, whose internal state can be controlled with ultrafast laser pulses, by trapping them in the vicinity of a trapped ion.

  4. Variation of carrier concentration and interface trap density in 8MeV electron irradiated c-Si solar cells

    SciTech Connect (OSTI)

    Bhat, Sathyanarayana, E-mail: asharao76@gmail.com; Rao, Asha, E-mail: asharao76@gmail.com [Department of Physics, Mangalore Institute of Technology and Engineering, Moodabidri, Mangalore-574225 (India); Krishnan, Sheeja [Department of Physics, Sri Devi Institute of Technology, Kenjar, Mangalore-574142 (India); Sanjeev, Ganesh [Microtron Centre, Department of Physics, Mangalore University, Mangalagangothri-574199 (India); Suresh, E. P. [Solar Panel Division, ISRO Satellite Centre, Bangalore-560017 (India)

    2014-04-24T23:59:59.000Z

    The capacitance and conductance measurements were carried out for c-Si solar cells, irradiated with 8 MeV electrons with doses ranging from 5kGy – 100kGy in order to investigate the anomalous degradation of the cells in the radiation harsh environments. Capacitance – Voltage measurements indicate that there is a slight reduction in the carrier concentration upon electron irradiation due to the creation of radiation induced defects. The conductance measurement results reveal that the interface state densities and the trap time constant increases with electron dose due to displacement damages in c-Si solar cells.

  5. Two-stream cyclotron radiative instabilities due to the marginally mirror-trapped fraction for fustion alphas in tokamaks

    SciTech Connect (OSTI)

    Arunasalam, V.

    1995-07-01T23:59:59.000Z

    It is shown here that the marginally mirror-trapped fraction of the newly-born fusion alpha particles in the deuterium-tritium (DT) reaction dominated tokamak plasmas can induce a two-stream cyclotron radiative instability for the fast Alfven waves propagating near the harmonics of the alpha particle cyclotron frequency {omega}{sub c{alpha}}. This can explain both the experimentally observed time behavior and the spatially localized origin of the fusion product ion cyclotron emission (ICE) in TFTR at frequencies {omega} {approx} m{omega}{sub c{alpha}}.

  6. Characterization of particle- and vapor-phase organic fraction emissions from a heavy-duty diesel engine equipped with a particle trap and regeneration controls

    SciTech Connect (OSTI)

    Bagley, S.T.; Gratz, L.D.; Leddy, D.G.; Johnson, J.H. (Michigan Technological Univ., Houghton, MI (United States))

    1993-07-01T23:59:59.000Z

    The effects of a ceramic particle trap on the chemical and biological character of the exhaust from a heavy-duty diesel engine have been studied during steady-state operation and during periods of trap regeneration. Phase I of this project involved developing and refining the methods using a Caterpillar 3208 engine, and Phase II involved more detailed experiments with a Cummins LTA10-300 engine, which met Federal 1988 particulate matter standards, and a ceramic particle trap with built-in regeneration controls. During the Phase I experiments, samples wee collected at the Environmental Protection Agency (EPA)* steady-state mode 4 (50% load at intermediate speed). Varying the dilution ratio to obtain a constant filter-face temperature resulted in less variability in total particulate matter (TPM), particle-associated soluble organic fraction (SOF), solids (SOL), and polynuclear aromatic hydrocarbon (PAH) levels than sampling with a constant dilution ratio and allowing filter-face temperature to vary. A modified microsuspension Ames assay detected mutagenicity in the SOF samples, and in the semivolatile organic fraction extracted from XAD-2 resin (XAD-2 resin organic component, XOC) with at least 10 times less sample mass than the standard plate incorporation assay. Measurement techniques for PAH and nitro-PAH in the SOF and XOC also were developed during this portion of the project. For the Phase II work, two EPA steady-state rated speed modes were selected: mode 11 (25% load) and mode 9 (75% load). With or without the trap, filter-face temperatures were kept at 45 degrees +/- 2 degrees C, nitrogen dioxide (NO2) levels less than 5 parts per million (ppm), and sampling times less than 60 minutes. Particle sizes were determined using an electrical aerosol analyzer. Similar sampling methods were used when the trap was regenerated, except that a separate dilution tunnel and sampling system was designed and built to collect all of the regeneration emissions.

  7. Synergies of High-Efficiency Clean Combustion and Lean NOx Trap...

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

    Combustion and Lean NOx Trap Catalysts investigation of potential synergies of low emission advanced combustion techniques and advanced lean exhaust catalytic aftertreatment....

  8. E-Print Network 3.0 - aggregation pheromone traps Sample Search...

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

    pheromone-baited traps... of WPB caught in ... Source: Erbilgin, Nadir - Department of Renewable Resources, University of Alberta Collection: Biology and Medicine ;...

  9. Bose-Einstein condensate in traps: A Diffusion Monte Carlo analysis

    E-Print Network [OSTI]

    Glyde, Henry R.

    Bosons, we note that the energy of a single particle in a typical harmonic trap (e.g. 87 Rb) is (3/2)¯hho

  10. E-Print Network 3.0 - ap-8 trapped proton Sample Search Results

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

    J. Bebek, Armin Karcher, William F. Kolbe, Natalie A. Roe, Summary: Charge trap identification for proton-irradiated p+ channel CCDs Nick J. Mostek, Christopher J... , we...

  11. E-Print Network 3.0 - antiproton trap hipat Sample Search Results

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

    of - Department of Physics, Non-Neutral Plasma Project Collection: Plasma Physics and Fusion 12 Cold Trapped Positrons and Progress to Cold Antihydrogen Summary: over a wide...

  12. E-Print Network 3.0 - aerosol trapping effect Sample Search Results

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

    of this infrared radiation is trapped... 'S TEMPERATURE IS RISING This is the greenhouse effect. Without it, the Earths climate would be ... Source: Brookhaven National...

  13. Comparison of methods to quantify interface trap densities at dielectric/IIIV semiconductor interfaces

    E-Print Network [OSTI]

    Stemmer, Susanne

    2010-01-01T23:59:59.000Z

    and a series resistance R s . ?c? Equivalent circuit of theresistance, R s . The in- terface trap density contributes an equivalent

  14. QUANTUM SIMULATIONS OF THE ISING MODEL WITH TRAPPED IONS: DEVIL'S STAIRCASE AND ARBITRARY LATTICE PROPOSAL .

    E-Print Network [OSTI]

    Korenblit, Simcha

    2013-01-01T23:59:59.000Z

    ??A collection of trapped atomic ions represents one of the most attractive platforms for the quantum simulation of interacting spin networks and quantum magnetism. Spin-dependent… (more)

  15. Effect of atomic scale plasticity on hydrogen diffusion in iron: Quantum mechanically informed and on-the-fly kinetic

    E-Print Network [OSTI]

    Ortiz, Michael

    viewpoints, is futile. Among several mechanisms proposed for hydrogen embrittlement (HE) of metals, hydrogenEffect of atomic scale plasticity on hydrogen diffusion in iron: Quantum mechanically informed-assisted diffusion and trapping of hydrogen by crystalline defects in iron. Given an embedded atom (EAM) potential

  16. Mechanical Engineering ME 3720 FLUID MECHANICS

    E-Print Network [OSTI]

    Panchagnula, Mahesh

    Mechanical Engineering ME 3720 FLUID MECHANICS Pre-requisite: ME 2330 Co-requisite: ME 3210) to develop an understanding of the physical mechanisms and the mathematical models of fluid mechanics of fluid mechanics problems in engineering practice. The basic principles of fluid mechanics

  17. Intrinsic Time Quantum Geometrodynamics

    E-Print Network [OSTI]

    Eyo Eyo Ita III; Chopin Soo; Hoi-Lai Yu

    2015-02-06T23:59:59.000Z

    Quantum Geometrodynamics with intrinsic time development and momentric variables is presented. An underlying SU(3) group structure at each spatial point regulates the theory. The intrinsic time behavior of the theory is analyzed, together with its ground state and primordial quantum fluctuations. Cotton-York potential dominates at early times when the universe was small; the ground state naturally resolves Penrose's Weyl Curvature Hypothesis, and thermodynamic and gravitational `arrows of time' point in the same direction. Ricci scalar potential corresponding to Einstein's General Relativity emerges as a zero-point energy contribution. A new set of fundamental commutation relations without Planck's constant emerges from the unification of Gravitation and Quantum Mechanics.

  18. Intrinsic Time Quantum Geometrodynamics

    E-Print Network [OSTI]

    Eyo Eyo Ita III; Chopin Soo; Hoi-Lai Yu

    2015-01-26T23:59:59.000Z

    Quantum Geometrodynamics with intrinsic time development and momentric variables is presented. An underlying SU(3) group structure at each spatial point regulates the theory. The intrinsic time behavior of the theory is analyzed, together with its ground state and primordial quantum fluctuations. Cotton-York potential dominates at early times when the universe was small; the ground state naturally resolves Penrose's Weyl Curvature Hypothesis, and thermodynamic and gravitational `arrows of time' point in the same direction. Ricci scalar potential corresponding to Einstein's General Relativity emerges as a zero-point energy contribution. A new set of fundamental canonical commutation relations without Planck's constant emerges from the unification of Gravitation and Quantum Mechanics.

  19. Dudley Ridge, a geomorphic trap - lacustrine gas in California

    SciTech Connect (OSTI)

    Sugden, H.E.

    1986-04-01T23:59:59.000Z

    The Dudley Ridge gas field is about 6 mi southeast of Kettleman City, California. The abandoned field straddles the boundary between T23S, R19E, and T23S, R20E, MDBM, in Kings County, California. The Tulare Lake depression was formed during the Pleistocene. It is bounded by the Temblor Range on the west, the Sierra Nevada rise on the east, the north tilt of the San Joaquin Valley to the south, and a gentle rise in the San Joaquin Valley floor to the north. The depression is almost circular except for the west side where North Kettleman dome formed a peninsula. The prevailing longshore current was to the south due to Coriolis-directed winds. Dudley Ridge was formed as a spit, trailing south off the side of North Kettleman dome. The spit is sandy, silty clay, with sand lense onlaps. The geomorphic trap formed by the sand lenses serves as a trap for the methane gas being produced in the organic-rich lake-bed sediments.

  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. Mechanical & Aerospace Engineering

    E-Print Network [OSTI]

    Mechanical & Aerospace Engineering An experimental methodology is presented for mechanism verification of physics-based prognosis of mechanical damage, such as fatigue. The proposed experimental methodology includes multi-resolution in-situ mechanical testing, advanced imaging analysis, and mechanism

  2. On the foundation of Mechanics

    E-Print Network [OSTI]

    Ricardo J. Alonso-Blanco; Jesús Muñoz-Díaz

    2014-12-09T23:59:59.000Z

    This note is an extended version of "A note on the foundations of Mechanics", arXiv: 1404.1321 [math-ph]. A presentation of its contents was given in a talk in memorial homage to the professor Juan B. Sancho Guimer\\'a. For this reason, it was written in spanish language. The matter of the note is a systematic foundation of the most classical part of Mechanics. The content by sections is: 0) Notions and basic results, 1) Conservative systems 2) Time. Time constraints, 3) Proper time. Relativistic forces, 4) Electromagnetic fields, 5) On the Hamilton-Noether Principle, 6) Schr\\"odinger equation.

  3. Ion Crystals Produced by Laser and Sympathetic Cooling in a Linear RF Ion Trap

    E-Print Network [OSTI]

    Zhu, Feng

    2012-02-14T23:59:59.000Z

    A detailed investigation of ion crystals produced by laser and sympathetic cooling in a linear RF trap has been conducted. The laser cooling methods were examined and applied to the trapped ^24Mg^(positive) ions. The crystals produced by the laser...

  4. Trapping cold atoms using surface-grown carbon nanotubes P. G. Petrov,1,* S. Machluf,1

    E-Print Network [OSTI]

    Joselevich, Ernesto

    Trapping cold atoms using surface-grown carbon nanotubes P. G. Petrov,1,* S. Machluf,1 S. Younis,1 atomic clouds into magnetic traps created by single-wall carbon nanotubes grown directly onto dielectric surfaces. We show that atoms may be captured for experimen- tally sustainable nanotube currents, generating

  5. Optica Applicata Vol. XXVIII, No. 3, str. 239, 1998 Magneto-Optical Trap for Rubidium Atoms

    E-Print Network [OSTI]

    1 Optica Applicata Vol. XXVIII, No. 3, str. 239, 1998 Magneto-Optical Trap for Rubidium Atoms Jerzy of the lasers used in the set-up. 1. Introduction Atomic physics has noticed recently a rapid development of research on different methods of cooling and trapping of atoms with use of optical forces (light pressure

  6. Cooling and Trapping Atoms Atoms are slowed and cooled by radiation pressure from laser light

    E-Print Network [OSTI]

    Johannesson, Henrik

    Cooling and Trapping Atoms Atoms are slowed and cooled by radiation pressure from laser light and then trapped in a bottle whose "walls" are magnetic fields. Cooled atoms are ideal for exploring basic. research has traditionally been the study of the intrinsic prop erties of isolated atoms. In the early part

  7. VOLUME 6S, NUMBER 13 PHYSICAL REVIEW LETTERS Very Cold Trapped Atoms in a Vapor Cell

    E-Print Network [OSTI]

    Monroe, Christopher

    VOLUME 6S, NUMBER 13 PHYSICAL REVIEW LETTERS Very Cold Trapped Atoms in a Vapor Cell 24 SEPTEMBER sample of spin-polarized trapped atoms. The technique used dramati- cally simplifies the production of laser-cooled atoms. In this experiment, 1.8x10' neutral cesium atoms were optically captured directly

  8. Cooling and Heating of the Quantum Motion of Trapped Cd+ Louis Deslauriers

    E-Print Network [OSTI]

    Monroe, Christopher

    of fluctuating electric fields with the motional state of the ion leads to heating and thus to decoherence of decoherence in ion traps and possibly other charge-based quantum systems. #12;Cooling and HeatingABSTRACT Cooling and Heating of the Quantum Motion of Trapped Cd+ Ions by Louis Deslauriers Chair

  9. PHYSICAL REVIEW E 84, 031108 (2011) Noise associated with nonconservative forces in optical traps

    E-Print Network [OSTI]

    La Porta, Arthur

    nonconservative fluctuations to direct thermal fluctuations scales inversely with the square root of trap power) It is known that for a particle held in an optical trap the interaction of thermal fluctuations by a force Fg proportional to the optical intensity gradient. The force exerted on the particle

  10. M4C3 precipitation in FeCMoV steels and relationship to hydrogen trapping

    E-Print Network [OSTI]

    Cambridge, University of

    , Pembroke Street, Cambridge CB2 3QZ, UK Strong steels suffer from embrittlement due to dissolved hydrogenM4C3 precipitation in Fe­C­Mo­V steels and relationship to hydrogen trapping BY S. YAMASAKI AND H, a phenomenon which can be mitigated by trapping the hydrogen at carbide particles, where it is rendered benign

  11. MATERIALS, METHODS, AND INSTRUMENTATION FOR PREPARATIVE-SCALE ISOELECTRIC TRAPPING SEPARATIONS

    E-Print Network [OSTI]

    North, Robert Yates

    2011-08-08T23:59:59.000Z

    MATERIALS, METHODS, AND INSTRUMENTATION FOR PREPARATIVE- SCALE ISOELECTRIC TRAPPING SEPARATIONS A Dissertation by ROBERT YATES NORTH Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of DOCTOR OF PHILOSOPHY May 2009 Major Subject: Chemistry MATERIALS, METHODS, AND INSTRUMENTATION FOR PREPARATIVE- SCALE ISOELECTRIC TRAPPING SEPARATIONS A Dissertation by ROBERT YATES NORTH...

  12. Joule heating effects on electrokinetic focusing and trapping of particles in constriction microchannels

    E-Print Network [OSTI]

    Xuan, Xiangchun "Schwann"

    Joule heating effects on electrokinetic focusing and trapping of particles in constriction for more Home Search Collections Journals About Contact us My IOPscience #12;IOP PUBLISHING JOURNAL.1088/0960-1317/22/7/075011 Joule heating effects on electrokinetic focusing and trapping of particles in constriction microchannels

  13. Fundamental limit of light trapping in grating Zongfu Yu, Aaswath Raman and Shanhui Fan+

    E-Print Network [OSTI]

    Fan, Shanhui

    ­305 (1982). 5. M. A. Green, "Lambertian light trapping in textured solar cells and light-emitting diodes. I. Tobías, A. Luque, and A. Marti, "Light intensity enhancement by diffracting structures in solar of nanophotonic light trapping for solar cells," arXiv:1004.2902v2 [physics.optics] (2010). http

  14. Silicon Solar Cell Light-Trapping Using Defect Mode Photonic Kelsey A. Whitesell*a

    E-Print Network [OSTI]

    Atwater, Harry

    Silicon Solar Cell Light-Trapping Using Defect Mode Photonic Crystals Kelsey A. Whitesell to enhance performance of thin film solar cells because of their unique ability to control light. We show for light trapping in thin film photovoltaics. Keywords: photonic crystals, defect, silicon, solar cell

  15. Light Trapping Textures Designed by Electromagnetic Optimization for Sub-Wavelength Thick Solar Cells

    E-Print Network [OSTI]

    California at Irvine, University of

    Light Trapping Textures Designed by Electromagnetic Optimization for Sub-Wavelength Thick Solar Sciences Division, Lawrence Berkeley National Laboratory July 23, 2013 Abstract Light trapping in solar the surface of the solar cell, where n is the material refractive index. This ray-optics absorption

  16. Light trapping design for low band-gap polymer solar cells

    E-Print Network [OSTI]

    John, Sajeev

    Light trapping design for low band-gap polymer solar cells Stephen Foster1,* and Sajeev John1,2 1 demonstrate numerically a 2-D nanostructured design for light trapping in a low band-gap polymer solar cell, "Light harvesting improvement of organic solar cells with self- enhanced active layer designs," Opt

  17. Title of dissertation: ULTRAFAST CONTROL OF SPIN AND MOTION IN TRAPPED IONS

    E-Print Network [OSTI]

    Monroe, Christopher

    , I report here on the first experiments using ultrafast laser pulses to control the internalABSTRACT Title of dissertation: ULTRAFAST CONTROL OF SPIN AND MOTION IN TRAPPED IONS Jonathan and external states of a single trapped ion. I begin with experiments in ultrafast spin control, showing how

  18. 3D modeling of magnetic atom traps on type-II superconductor chips

    E-Print Network [OSTI]

    Prigozhin, Leonid

    Israel 2 A. Yersin Department of Solar Energy and Environmental Physics, The Blaustein Institutes. The proposed approach allows us to predict important characteristics of the magnetic traps (their depth, shape, and in the usage of trapped atoms to probe local irregularities of magnetic and electric fields near conductive

  19. NEUTRON LIFETIME EXPERIMENT USING UCN STORAGE IN AN `ACCORDION-LIKE' TRAP

    E-Print Network [OSTI]

    Steyerl, Albert

    NEUTRON LIFETIME EXPERIMENT USING UCN STORAGE IN AN `ACCORDION-LIKE' TRAP BY ASHISH M. DESAI determination of the neutron lifetime has an impact on particle physics and cosmology. We report progress towards a measurement of the neutron lifetime using an accordion-like storage trap. Ultracold neutrons

  20. Poverty Trap with Convex Production Function: The role of Public and Private Capital

    E-Print Network [OSTI]

    Bandyopadhyay, Antar

    Poverty Trap with Convex Production Function: The role of Public and Private Capital Kumar Aniket University of Cambridge 20 September 2014 Abstract. The objective of the paper is to explain why poverty, there is a poverty trap region or a threshold below which the economy is in a low steady state. The paper shows

  1. NREL experiments show that disordered inverse opals significantly scatter and trap near-infrared light, with

    E-Print Network [OSTI]

    NREL experiments show that disordered inverse opals significantly scatter and trap near-infrared wavelengths in the near-infrared (NIR), which is important to a number of technologies. This discovery.neale@nrel.gov Reference: N.R. Neale, B.G. Lee, S.H. Kang, and A.J. Frank."Near-Infrared Light Trapping in Disordered

  2. Dynamical quantum noise in trapped Bose-Einstein condensates M. J. Steel,1,2

    E-Print Network [OSTI]

    Queensland, University of

    Dynamical quantum noise in trapped Bose-Einstein condensates M. J. Steel,1,2 M. K. Olsen,1, * L. I introduce the study of dynamical quantum noise in Bose-Einstein condensates through numerical simu- lation equations for a single trapped condensate in both the positive-P and Wigner representations and perform

  3. Kinetics for evaporative cooling of a trapped gas Kirstine BergSrensen \\Lambda

    E-Print Network [OSTI]

    Berg-Sørensen, Kirstine

    the kinetic theory for evaporative cooling of a dilute collisional gas in a trap. The analysis in 0. J. Luiten and increase the phase­space density of an atomic, bosonic gas towards a Bose­Einstein condensate (BECKinetics for evaporative cooling of a trapped gas Kirstine Berg­Sørensen \\Lambda The Rowland

  4. Laser Stabilization for Quantum Computing with Trapped Barium ions Corey Adams

    E-Print Network [OSTI]

    Blinov, Boris

    Laser Stabilization for Quantum Computing with Trapped Barium ions Corey Adams University of Rochester (Dated: November 11, 2009) ABSTRACT The goal of this project was to stabilize a laser cooling system used to trap and cool Ba+ ions used for quantum computation research. The lasers, at 650 and 985

  5. Quantum Reactive Scattering of Ultracold NHX 3 Radicals in a Magnetic Trap

    E-Print Network [OSTI]

    trap using Stark deceleration [23,24] and buffer gas cooling techniques [15,25,26], and earlier cooling more difficult than previously anticipated. DOI: 10.1103/PhysRevLett.110.063201 PACS numbers: 34 cooling. These second-stage cooling methods, which rely on strong elastic collisions between trapped

  6. Ultracold molecules for the masses: evaporative cooling and magneto-optical trapping

    E-Print Network [OSTI]

    Jin, Deborah

    cooling, until now none of these techniques have been applicable to molecules. In this thesis, two majorUltracold molecules for the masses: evaporative cooling and magneto-optical trapping by B. K. Stuhl for the masses: evaporative cooling and magneto-optical trapping written by B. K. Stuhl has been approved

  7. ccsd00000593 Collective modes of a trapped Lieb-Liniger gas

    E-Print Network [OSTI]

    ccsd­00000593 (version 1) : 11 Sep 2003 Collective modes of a trapped Lieb-Liniger gas September 11, 2003) We consider a trapped repulsive one-dimensional (1D) Bose gas at very low temperature, where the gas is locally described by the Lieb-Liniger model of bosons interacting via a repulsive delta

  8. Title of dissertation: QUANTUM SIMULATIONS OF THE ISING MODEL WITH TRAPPED IONS

    E-Print Network [OSTI]

    Monroe, Christopher

    are intractable. #12;QUANTUM SIMULATIONS OF THE ISING MODEL WITH TRAPPED IONS: DEVIL'S STAIRCASE AND ARBITRARYABSTRACT Title of dissertation: QUANTUM SIMULATIONS OF THE ISING MODEL WITH TRAPPED IONS: DEVIL'S STAIRCASE AND ARBITRARY LATTICE PROPOSAL Simcha Korenblit, Doctor of Philosophy 2013 Dissertation directed

  9. Spontaneous recoil effects of optical pumping on trapped atoms

    E-Print Network [OSTI]

    S. Wallentowitz; P. E. Toschek

    2008-08-08T23:59:59.000Z

    The recoil effects of spontaneous photon emissions during optical pumping of a trapped three-level atom are exactly calculated. Without resort to the Lamb-Dicke approximation, and considering arbitrary detuning and saturation of the pump laser, the density of recoil shifts in phase space is derived. It is shown that this density is not of Gaussian shape, and that it becomes isotropic in phase space only for a branching ratio corresponding to fluorescence scattering but unfavorable for optical pumping. The dependence of its anisotropy on the laser saturation is discussed in the resonant case, and the mapping of moments of the atom's center-of-mass motion due to the pumping is presented. Moreover, it is shown how optimum parameters for protecting the center-of-mass quantum state from pump-induced disturbance depend on the specific property to be protected.

  10. Weakly bound molecules trapped with discrete scaling symmetries

    E-Print Network [OSTI]

    Yusuke Nishida; Dean Lee

    2012-09-12T23:59:59.000Z

    When the scattering length is proportional to the distance from the center of the system, two particles are shown to be trapped about the center. Furthermore, their spectrum exhibits discrete scale invariance, whose scale factor is controlled by the slope of the scattering length. While this resembles the Efimov effect, our system has a number of advantages when realized with ultracold atoms. We also elucidate how the emergent discrete scaling symmetry is violated for more than two bosons, which may shed new light on Efimov physics. Our system thus serves as a tunable model system to investigate universal physics involving scale invariance, quantum anomaly, and renormalization group limit cycle, which are important in a broad range of quantum physics.

  11. Lean NOx Trap Catalysis for Lean Natural Gas Engine Applications

    SciTech Connect (OSTI)

    Parks, II, James E [ORNL; Storey, John Morse [ORNL; Theiss, Timothy J [ORNL; Ponnusamy, Senthil [ORNL; Ferguson, Harley Douglas [ORNL; Williams, Aaron M [ORNL; Tassitano, James B [ORNL

    2007-09-01T23:59:59.000Z

    Distributed energy is an approach for meeting energy needs that has several advantages. Distributed energy improves energy security during natural disasters or terrorist actions, improves transmission grid reliability by reducing grid load, and enhances power quality through voltage support and reactive power. In addition, distributed energy can be efficient since transmission losses are minimized. One prime mover for distributed energy is the natural gas reciprocating engine generator set. Natural gas reciprocating engines are flexible and scalable solutions for many distributed energy needs. The engines can be run continuously or occasionally as peak demand requires, and their operation and maintenance is straightforward. Furthermore, system efficiencies can be maximized when natural gas reciprocating engines are combined with thermal energy recovery for cooling, heating, and power applications. Expansion of natural gas reciprocating engines for distributed energy is dependent on several factors, but two prominent factors are efficiency and emissions. Efficiencies must be high enough to enable low operating costs, and emissions must be low enough to permit significant operation hours, especially in non-attainment areas where emissions are stringently regulated. To address these issues the U.S. Department of Energy and the California Energy Commission launched research and development programs called Advanced Reciprocating Engine Systems (ARES) and Advanced Reciprocating Internal Combustion Engines (ARICE), respectively. Fuel efficiency and low emissions are two primary goals of these programs. The work presented here was funded by the ARES program and, thus, addresses the ARES 2010 goals of 50% thermal efficiency (fuel efficiency) and <0.1 g/bhp-hr emissions of oxides of nitrogen (NOx). A summary of the goals for the ARES program is given in Table 1-1. ARICE 2007 goals are 45% thermal efficiency and <0.015 g/bhp-hr NOx. Several approaches for improving the efficiency and emissions of natural gas reciprocating engines are being pursued. Approaches include: stoichiometric engine operation with exhaust gas recirculation and three-way catalysis, advanced combustion modes such as homogeneous charge compression ignition, and extension of the lean combustion limit with advanced ignition concepts and/or hydrogen mixing. The research presented here addresses the technical approach of combining efficient lean spark-ignited natural gas combustion with low emissions obtained from a lean NOx trap catalyst aftertreatment system. This approach can be applied to current lean engine technology or advanced lean engines that may result from related efforts in lean limit extension. Furthermore, the lean NOx trap technology has synergy with hydrogen-assisted lean limit extension since hydrogen is produced from natural gas during the lean NOx trap catalyst system process. The approach is also applicable to other lean engines such as diesel engines, natural gas turbines, and lean gasoline engines; other research activities have focused on those applications. Some commercialization of the technology has occurred for automotive applications (both diesel and lean gasoline engine vehicles) and natural gas turbines for stationary power. The research here specifically addresses barriers to commercialization of the technology for large lean natural gas reciprocating engines for stationary power. The report presented here is a comprehensive collection of research conducted by Oak Ridge National Laboratory (ORNL) on lean NOx trap catalysis for lean natural gas reciprocating engines. The research was performed in the Department of Energy's ARES program from 2003 to 2007 and covers several aspects of the technology. All studies were conducted at ORNL on a Cummins C8.3G+ natural gas engine chosen based on industry input to simulate large lean natural gas engines. Specific technical areas addressed by the research include: NOx reduction efficiency, partial oxidation and reforming chemistry, and the effects of sulfur poisons on the partial oxidation

  12. Gyrotactic trapping in laminar and turbulent Kolmogorov flow

    E-Print Network [OSTI]

    Francesco Santamaria; Filippo De Lillo; Massimo Cencini; Guido Boffetta

    2014-10-07T23:59:59.000Z

    Phytoplankton patchiness, namely the heterogeneous distribution of microalgae over multiple spatial scales, dramatically impacts marine ecology. A spectacular example of such heterogeneity occurs in thin phytoplankton layers (TPLs), where large numbers of photosynthetic microorganisms are found within a small depth interval. Some species of motile phytoplankton can form TPLs by gyrotactic trapping due to the interplay of their particular swimming style (directed motion biased against gravity) and the transport by a flow with shear along the direction of gravity. Here we consider gyrotactic swimmers in numerical simulations of the Kolmogorov shear flow, both in laminar and turbulent regimes. In the laminar case, we show that the swimmer motion is integrable and the formation of TPLs can be fully characterized by means of dynamical systems tools. We then study the effects of rotational Brownian motion or turbulent fluctuations (appearing when the Reynolds number is large enough) on TPLs. In both cases we show that TPLs become transient, and we characterize their persistence.

  13. Gas turbine engine combustor can with trapped vortex cavity

    DOE Patents [OSTI]

    Burrus, David Louis; Joshi, Narendra Digamber; Haynes, Joel Meier; Feitelberg, Alan S.

    2005-10-04T23:59:59.000Z

    A gas turbine engine combustor can downstream of a pre-mixer has a pre-mixer flowpath therein and circumferentially spaced apart swirling vanes disposed across the pre-mixer flowpath. A primary fuel injector is positioned for injecting fuel into the pre-mixer flowpath. A combustion chamber surrounded by an annular combustor liner disposed in supply flow communication with the pre-mixer. An annular trapped dual vortex cavity located at an upstream end of the combustor liner is defined between an annular aft wall, an annular forward wall, and a circular radially outer wall formed therebetween. A cavity opening at a radially inner end of the cavity is spaced apart from the radially outer wall. Air injection first holes are disposed through the forward wall and air injection second holes are disposed through the aft wall. Fuel injection holes are disposed through at least one of the forward and aft walls.

  14. Lean Gasoline Engine Reductant Chemistry During Lean NOx Trap Regeneration

    SciTech Connect (OSTI)

    Choi, Jae-Soon [ORNL] [ORNL; Prikhodko, Vitaly Y [ORNL] [ORNL; Partridge Jr, William P [ORNL] [ORNL; Parks, II, James E [ORNL; Norman, Kevin M [ORNL] [ORNL; Huff, Shean P [ORNL] [ORNL; Chambon, Paul H [ORNL] [ORNL; Thomas, John F [ORNL] [ORNL

    2010-01-01T23:59:59.000Z

    Lean NOx Trap (LNT) catalysts can effectively reduce NOx from lean engine exhaust. Significant research for LNTs in diesel engine applications has been performed and has led to commercialization of the technology. For lean gasoline engine applications, advanced direct injection engines have led to a renewed interest in the potential for lean gasoline vehicles and, thereby, a renewed demand for lean NOx control. To understand the gasoline-based reductant chemistry during regeneration, a BMW lean gasoline vehicle has been studied on a chassis dynamometer. Exhaust samples were collected and analyzed for key reductant species such as H2, CO, NH3, and hydrocarbons during transient drive cycles. The relation of the reductant species to LNT performance will be discussed. Furthermore, the challenges of NOx storage in the lean gasoline application are reviewed.

  15. Laser cooling of a trapped particle with increased Rabi frequencies

    E-Print Network [OSTI]

    Tony Blake; Andreas Kurcz; Norah S. Saleem; Almut Beige

    2011-10-14T23:59:59.000Z

    This paper analyses the cooling of a single particle in a harmonic trap with red-detuned laser light with fewer approximations than previously done in the literature. We avoid the adiabatic elimination of the excited atomic state but are still interested in Lamb-Dicke parameters $\\eta \\ll 1$. Our results show that the Rabi frequency of the cooling laser can be chosen higher than previously assumed, thereby increasing the effective cooling rate but {\\em not} affecting the final outcome of the cooling process. Since laser cooling is already a well established experimental technique, the main aim of this paper is to present a model which can be extended to more complex scenarios, like cavity-mediated laser cooling.

  16. Loopless non-trapping invasion percolation model for fracking

    E-Print Network [OSTI]

    Norris, J Quinn; Rundle, John B

    2014-01-01T23:59:59.000Z

    Recent developments in hydraulic fracturing (fracking) have enabled the recovery of large quantities of natural gas and oil from old, low permeability shales. These developments include a change from low-volume, high-viscosity fluid injection to high-volume, low-viscosity injection. The injected fluid introduces distributed damage that provides fracture permeability for the extraction of the gas and oil. In order to model this process, we utilize a loopless non-trapping invasion percolation previously introduced to model optimal polymers in a strongly disordered medium, and for determining minimum energy spanning trees on a lattice. We performed numerical simulations on a 2D square lattice and find significant differences from other percolation models. Additionally, we find that the growing fracture network satisfies both Horton-Strahler and Tokunaga network statistics. As with other invasion percolation models, our model displays burst dynamics, in which the cluster extends rapidly into a connected region. W...

  17. Efficient Photoionization-Loading of Trapped Cadmium Ions with Ultrafast Pulses

    E-Print Network [OSTI]

    L. Deslauriers; M. Acton; B. B. Blinov; K. -A. Brickman; P. C. Haljan; W. K. Hensinger; D. Hucul; S. Katnik; R. N. Kohn, Jr.; P. J. Lee; M. J. Madsen; P. Maunz; S. Olmschenk; D. L. Moehring; D. Stick; J. Sterk; M. Yeo; K. C. Younge; C. Monroe

    2006-08-04T23:59:59.000Z

    Atomic cadmium ions are loaded into radiofrequency ion traps by photoionization of atoms in a cadmium vapor with ultrafast laser pulses. The photoionization is driven through an intermediate atomic resonance with a frequency-quadrupled mode-locked Ti:Sapphire laser that produces pulses of either 100 fsec or 1 psec duration at a central wavelength of 229 nm. The large bandwidth of the pulses photoionizes all velocity classes of the Cd vapor, resulting in high loading efficiencies compared to previous ion trap loading techniques. Measured loading rates are compared with a simple theoretical model, and we conclude that this technique can potentially ionize every atom traversing the laser beam within the trapping volume. This may allow the operation of ion traps with lower levels of background pressures and less trap electrode surface contamination. The technique and laser system reported here should be applicable to loading most laser-cooled ion species.

  18. Penning traps with unitary architecture for storage of highly charged ions

    E-Print Network [OSTI]

    Tan, Joseph N; Guise, Nicholas D; 10.1063/1.3685246

    2012-01-01T23:59:59.000Z

    Penning traps are made extremely compact by embedding rare-earth permanent magnets in the electrode structure. Axially-oriented NdFeB magnets are used in unitary architectures that couple the electric and magnetic components into an integrated structure. We have constructed a two- magnet Penning trap with radial access to enable the use of laser or atomic beams, as well as the collection of light. An experimental apparatus equipped with ion optics is installed at the NIST electron beam ion trap (EBIT) facility, constrained to fit within 1 meter at the end of a horizontal beamline for transporting highly charged ions. Highly charged ions of neon and argon, extracted with initial energies up to 4000 eV per unit charge, are captured and stored to study the confinement properties of a one-magnet trap and a two-magnet trap. Design considerations and some test results are discussed.

  19. Adiabatic electron response and solitary wave generation by trapped particle nonlinearity in a hydrogen plasma

    SciTech Connect (OSTI)

    Mandal, Debraj; Sharma, Devendra [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

    2014-10-15T23:59:59.000Z

    The finite amplitude ion acoustic waves that trap electrons modify the structure of the evolving nonlinear soliton solutions. In the numerical simulations, self-consistently generated solitary waves are studied that emerge as a result of a current driven microinstability growing the ion acoustic mode in a collisionless Vlasov plasma. The growth saturates as a result of nonlinear effects governed by a combination of nonlinearities originating from the hydrodynamic model and kinetic particle trapping effects. The resulting solitary waves also coexist with a finite current and an electron plasma wave capable of perturbing the trapping potential. The results of multiscale simulation are analyzed and characterized following the kinetic prescription of undamped trapped particle mode in the form of phase space vortex solutions that are generalized form of Sagdeev's solitons and obey the solutions of a modified Korteweg-de Vries equation, accounting for a stronger nonlinearity originating from the electron trapping.

  20. Low-temperature Bessel beam trap for single submicrometer aerosol particle studies

    SciTech Connect (OSTI)

    Lu, Jessica W.; Chasovskikh, Egor; Stapfer, David [Laboratory of Physical Chemistry, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich (Switzerland); Isenor, Merrill; Signorell, Ruth [Laboratory of Physical Chemistry, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich (Switzerland); Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1 (Canada)

    2014-09-01T23:59:59.000Z

    We report on a new instrument for single aerosol particle studies at low temperatures that combines an optical trap consisting of two counter-propagating Bessel beams (CPBBs) and temperature control down to 223 K (?50?°C). The apparatus is capable of capturing and stably trapping individual submicrometer- to micrometer-sized aerosol particles for up to several hours. First results from studies of hexadecane, dodecane, and water aerosols reveal that we can trap and freeze supercooled droplets ranging in size from ?450 nm to 5500 nm (radius). We have conducted homogeneous and heterogeneous freezing experiments, freezing-melting cycles, and evaporation studies. To our knowledge, this is the first reported observation of the freezing process for levitated single submicrometer-sized droplets in air using optical trapping techniques. These results show that a temperature-controlled CPBB trap is an attractive new method for studying phase transitions of individual submicrometer aerosol particles.

  1. PEBBLES Mechanics Simulation Speedup

    SciTech Connect (OSTI)

    Joshua J. Cogliati; Abderrafi M. Ougouag

    2010-05-01T23:59:59.000Z

    Pebble bed reactors contain large numbers of spherical fuel elements arranged randomly. Determining the motion and location of these fuel elements is required for calculating certain parameters of pebble bed reactor operation. These simulations involve hundreds of thousands of pebbles and involve determining the entire core motion as pebbles are recirculated. Single processor algorithms for this are insufficient since they would take decades to centuries of wall-clock time. This paper describes the process of parallelizing and speeding up the PEBBLES pebble mechanics simulation code. Both shared memory programming with the Open Multi-Processing API and distributed memory programming with the Message Passing Interface API are used in simultaneously in this process. A new shared memory lock-less linear time collision detection algorithm is described. This method allows faster detection of pebbles in contact than generic methods. These combine to make full recirculations on AVR sized reactors possible in months of wall clock time.

  2. Schwinger Mechanism with Stochastic Quantization

    E-Print Network [OSTI]

    Kenji Fukushima; Tomoya Hayata

    2014-06-23T23:59:59.000Z

    We prescribe a formulation of the particle production with real-time Stochastic Quantization. To construct the retarded and the time-ordered propagators we decompose the stochastic variables into positive- and negative-energy parts. In this way we demonstrate how to derive a standard formula for the Schwinger mechanism under time-dependent electric fields. We discuss a mapping to the Schwinger-Keldysh formalism and a relation to the classical statistical simulation.

  3. Relativistic viscoelastic fluid mechanics

    E-Print Network [OSTI]

    Masafumi Fukuma; Yuho Sakatani

    2011-09-01T23:59:59.000Z

    A detailed study is carried out for the relativistic theory of viscoelasticity which was recently constructed on the basis of Onsager's linear nonequilibrium thermodynamics. After rederiving the theory using a local argument with the entropy current, we show that this theory universally reduces to the standard relativistic Navier-Stokes fluid mechanics in the long time limit. Since effects of elasticity are taken into account, the dynamics at short time scales is modified from that given by the Navier-Stokes equations, so that acausal problems intrinsic to relativistic Navier-Stokes fluids are significantly remedied. We in particular show that the wave equations for the propagation of disturbance around a hydrostatic equilibrium in Minkowski spacetime become symmetric hyperbolic for some range of parameters, so that the model is free of acausality problems. This observation suggests that the relativistic viscoelastic model with such parameters can be regarded as a causal completion of relativistic Navier-Stokes fluid mechanics. By adjusting parameters to various values, this theory can treat a wide variety of materials including elastic materials, Maxwell materials, Kelvin-Voigt materials, and (a nonlinearly generalized version of) simplified Israel-Stewart fluids, and thus we expect the theory to be the most universal description of single-component relativistic continuum materials. We also show that the presence of strains and the corresponding change in temperature are naturally unified through the Tolman law in a generally covariant description of continuum mechanics.

  4. Construction and Operational Experience with a Superconducting Octupole Used to Trap Antihydrogen

    SciTech Connect (OSTI)

    Wanderer P.; Escallier, J.; Marone, A.; Parker, B.

    2011-09-06T23:59:59.000Z

    A superconducting octupole magnet has seen extensive service as part of the ALPHA experiment at CERN. ALPHA has trapped antihydrogen, a crucial step towards performing precision measurements of anti-atoms. The octupole was made at the Direct Wind facility by the Superconducting Magnet Division at Brookhaven National Laboratory. The magnet was wound with a six-around-one NbTi cable about 1 mm in diameter. It is about 300 mm long, with a radius of 25 mm and a peak field at the conductor of 4.04 T. Specific features of the magnet, including a minimal amount of material in the coil and coil ends with low multipole content, were advantageous to its use in ALPHA. The magnet was operated for six months a year for five years. During this time it underwent about 900 thermal cycles (between 4K and 100K). A novel operational feature is that during the course of data-taking the magnet was repeatedly shut off from its 950 A operating current. The magnet quenches during the shutoff, with a decay constant of 9 ms. Over the course of the five years, the magnet was deliberately quenched many thousands of times. It still performs well.

  5. Initial Data for General Relativity Containing a Marginally Outer Trapped Torus

    E-Print Network [OSTI]

    Sascha Husa

    1996-06-15T23:59:59.000Z

    Asymptotically flat, time-symmetric, axially symmetric and conformally flat initial data for vacuum general relativity are studied numerically on $R^3$ with the interior of a standard torus cut out. By the choice of boundary condition the torus is marginally outer trapped, and thus a surface of minimal area. Apart from pure scaling the standard tori are parameterized by a radius $a\\in [0,1]$, where $a=0$ corresponds to the limit where the boundary torus degenerates to a circle and $a=1$ to a torus that touches the axis of symmetry. Noting that these tori are the orbits of a $U(1)\\times U(1)$ conformal isometry allows for a simple scheme to solve the constraint, involving numerical solution of only ordinary differential equations.The tori are unstable minimal surfaces (i.e. only saddle points of the area functional) and thus can not be apparent horizons, but are always surrounded by an apparent horizon of spherical topology, which is analyzed in the context of the hoop conjecture and isoperimetric inequality for black holes.

  6. PhD position in trapped ion quantum technology and nanoscience at the University of Sussex, Brighton, UK

    E-Print Network [OSTI]

    Hensinger, Winfried

    PhD position in trapped ion quantum technology and nanoscience at the University of Sussex a quantum computer with trapped ions. Research in the group focuses on the borderland of nanoscience

  7. MECH 502: Fluid Mechanics Winter semester 2010

    E-Print Network [OSTI]

    MECH 502: Fluid Mechanics Winter semester 2010 Instructor: I.A. Frigaard Times: Tuesdays week of semester. Location: CHBE 103 Synopsis: This course will focus primarily on fluid mechanics will be to look at fluid mechanics fundamentals, and at the mathematical modeling & analysis of simplified flow

  8. Black Silicon Solar Thin-film Microcells Integrating Top Nanocone Structures for Broadband and Omnidirectional Light-Trapping

    E-Print Network [OSTI]

    Xu, Zhida; Brueckner, Eric P; Li, Lanfang; Jiang, Jing; Nuzzo, Ralph G; Liu, Gang L

    2014-01-01T23:59:59.000Z

    Recently developed classes of monocrystalline silicon solar microcells (u-cell) can be assembled into modules with characteristics (i.e., mechanically flexible forms, compact concentrator designs, and high-voltage outputs) that would be impossible to achieve using conventional, wafer-based approaches. In this paper, we describe a highly dense, uniform and non-periodic nanocone forest structure of black silicon (bSi) created on optically-thin (30 um) u-cells for broadband and omnidirectional light-trapping with a lithography-free and high-throughput plasma texturizing process. With optimized plasma etching conditions and a silicon nitride passivation layer, black silicon u-cells, when embedded in a polymer waveguiding layer, display dramatic increases of as much as 65.7% in short circuit current, as compared to a bare silicon device. The conversion efficiency increases from 8% to 11.5% with a small drop in open circuit voltage and fill factor.

  9. Herpetological Review 36(3), 2005 277 in pipe-traps inserted upright into the ground, placed open-ended

    E-Print Network [OSTI]

    Johnson, Michele A.

    Herpetological Review 36(3), 2005 277 in pipe-traps inserted upright into the ground, placed open, Tregger 2004) similar pipe-trap designs have not succeeded in capturing large numbers of treefrogs. The large number of captures reported in this study indicate that this new pipe-trap design may be more

  10. Bose-Einstein condensation in dark power-law laser traps

    SciTech Connect (OSTI)

    Jaouadi, A. [Universite Paris-Sud, Institut des Sciences Moleculaires d'Orsay (ISMO), F-91405 Orsay (France); CNRS, Orsay, F-91405 France (France); Laboratoire de Spectroscopie Atomique, Moleculaire et Applications (LSAMA), Department of Physics, Faculty of Science of Tunis, University of Tunis El Manar, T-2092 Tunis (Tunisia); Gaaloul, N. [Institut fuer Quantenoptik, Welfengarten 1, Gottfried Wilhelm Leibniz Universitaet, D-30167 Hannover (Germany); Viaris de Lesegno, B.; Pruvost, L. [CNRS, Laboratoire Aime Cotton (LAC), F-91405 Orsay (France); Universite Paris-Sud, Orsay, F-91405 France (France); Telmini, M. [Laboratoire de Spectroscopie Atomique, Moleculaire et Applications (LSAMA), Department of Physics, Faculty of Science of Tunis, University of Tunis El Manar, T-2092 Tunis (Tunisia); Charron, E. [Universite Paris-Sud, Institut des Sciences Moleculaires d'Orsay (ISMO), F-91405 Orsay (France); CNRS, Orsay, F-91405 (France)

    2010-08-15T23:59:59.000Z

    We investigate theoretically an original route to achieve Bose-Einstein condensation using dark power-law laser traps. We propose to create such traps with two crossing blue-detuned Laguerre-Gaussian optical beams. Controlling their azimuthal order l allows for the exploration of a multitude of power-law trapping situations in one, two, and three dimensions, ranging from the usual harmonic trap to an almost square-well potential, in which a quasihomogeneous Bose gas can be formed. The usual cigar-shaped and disk-shaped Bose-Einstein condensates obtained in a 1D or 2D harmonic trap take the generic form of a 'finger' or of a 'hockey puck' in such Laguerre-Gaussian traps. In addition, for a fixed atom number, higher transition temperatures are obtained in such configurations when compared with a harmonic trap of the same volume. This effect, which results in a substantial acceleration of the condensation dynamics, requires a better but still reasonable focusing of the Laguerre-Gaussian beams.

  11. Calculation of geometric phases in electric dipole searches with trapped spin-1/2 particles based on direct solution of the Schrödinger equation

    E-Print Network [OSTI]

    A. Steyerl; C. Kaufman; G. Müller; S. S. Malik; A. M. Desai; R. Golub

    2014-05-23T23:59:59.000Z

    Pendlebury $\\textit{et al.}$ [Phys. Rev. A $\\textbf{70}$, 032102 (2004)] were the first to investigate the role of geometric phases in searches for an electric dipole moment (EDM) of elementary particles based on Ramsey-separated oscillatory field magnetic resonance with trapped ultracold neutrons and comagnetometer atoms. Their work was based on the Bloch equation and later work using the density matrix corroborated the results and extended the scope to describe the dynamics of spins in general fields and in bounded geometries. We solve the Schr\\"odinger equation directly for cylindrical trap geometry and obtain a full description of EDM-relevant spin behavior in general fields, including the short-time transients and vertical spin oscillation in the entire range of particle velocities. We apply this method to general macroscopic fields and to the field of a microscopic magnetic dipole.

  12. Smolt Condition and Timing of Arrival at Lower Granite Reservoir, 1987 Annual Report.

    SciTech Connect (OSTI)

    Buettner, Edwin W.; Nelson, V. Lance

    1990-01-01T23:59:59.000Z

    This project monitored the daily passage of smolts during the 1988 spring outmigration at two migrant traps; one each on the Snake and Clearwater rivers. Due to the low runoff year, chinook salmon catch at the Snake River trap was very low. Steelhead trout catch was higher than normal, probably due to trap modifications and because the trap was moved to the east side of the river. Chinook salmon and steelhead trout catch at the Clearwater River trap was similar to 1987. Total cumulative recovery of PIT tagged fish at the three dams, with PIT tag detection systems was: 55% for chinook salmon, 73% for hatchery steelhead trout, and 75% for wild steelhead trout. Travel time through Lower Granite Reservoir for PIT tagged chinook salmon and steelhead trout, marked at the head of the reservoir, was affected by discharge. Statistical analysis showed that as discharge increased from 40 kcfs to 80 kcfs, chinook salmon travel time decreased three fold, and steelhead trout travel time decreased two fold. There was a statistical difference between estimates of travel time through Lower Granite Reservoir for PIT tagged and freeze branded steelhead trout, but not for chinook salmon. These differences may be related to the estimation techniques used for PIT tagged and freeze branded groups, rather than real differences in travel time. 10 figs, 15 tabs.

  13. Mechanical and Aerospace Engineering

    E-Print Network [OSTI]

    Mechanical and Aerospace Engineering seminar Three Dimensional Traction Force Microscopy with Applications in Cell Mechanics abstract The interactions between biochemical and mechanical signals during-dimensional measurement techniques are needed to investigate the effect of mechanical properties of the substrate

  14. Mechanical Engineer Company Description

    E-Print Network [OSTI]

    Kostic, Milivoje M.

    Mechanical Engineer Company Description Control Solutions Inc. is a small, dynamic, and rapidly. Position Description The Mechanical Engineer is responsible for all aspects associated with the mechanical enclosures, brackets, cabling assemblies among others. Systems include mechanisms, sensors, hydraulics, among

  15. MECHANICAL ENGINEERING Ross Schlueter

    E-Print Network [OSTI]

    MECHANICAL ENGINEERING Ross Schlueter Engineering Deputy For Mechanical Engineering Russ Wells Mechanical Engineering Department Deputy ELECTRONICS, SOFTWARE & INSTRUMENTATION ENGINEERING Henrik von Der Sen Mechanical Admin. Assist. Joan Wolter Electronics Admin. Assist. Marilyn Wong Division Admin

  16. 2-photon ionization and necessary laser and vacuum systems for experiments with trapped strontium ions

    E-Print Network [OSTI]

    E. Kirilov; S. Putterman

    2007-12-03T23:59:59.000Z

    We describe a efficient way to photoionize strontium atoms in a linear radio-frequency trap. We use a 2-photon second order process to excite the autoionization resonance (4d2 + 5p2) 1D2. A doubled pulsed Ti:Saphire laser system is used at 431nm to provide 100fsec pulses at 82Mhz. The fabrication of the laser systems for addressing the Sr+ transitions necessary for laser cooling and excitation of quantum jumps, vacuum system and ion trap structure are also described in detail. With the current setup a easy and repeatable trapping of linear ion chains is achieved at UHV pressures.

  17. Light Trapping for Thin Silicon Solar Cells by Femtosecond Laser Texturing: Preprint

    SciTech Connect (OSTI)

    Lee, B. G.; Lin, Y. T.; Sher, M. J.; Mazur, E.; Branz, H. M.

    2012-06-01T23:59:59.000Z

    Femtosecond laser texturing is used to create nano- to micron-scale surface roughness that strongly enhances light-trapping in thin crystalline silicon solar cells. Light trapping is crucial for thin solar cells where a single light-pass through the absorber is insufficient to capture the weakly absorbed red and near-infrared photons, especially with an indirect-gap semiconductor absorber layer such as crystalline Si which is less than 20 um thick. We achieve enhancement of the optical absorption from light-trapping that approaches the Yablonovitch limit.

  18. Photoionization rates of Cs Rydberg atoms in a 1064-nm far-off-resonance trap

    SciTech Connect (OSTI)

    Tallant, J.; Booth, D.; Shaffer, J. P. [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 West Brooks Street, Norman, Oklahoma 73019 (United States)

    2010-12-15T23:59:59.000Z

    Experimental measurements of photoionization rates of nD{sub 5/2} Rydberg states of Cs (50{<=}n{<=}75) in a 1064-nm far off-resonance dipole trap are presented. The photoionization rates are obtained by measuring the lifetimes of Rydberg atoms produced inside of a 1064-nm far off-resonance trap and comparing the lifetimes to corresponding control experiments in a magneto-optical trap. Experimental results for the control experiments agree with recent theoretical predictions for Rydberg state lifetimes and measured photoionization rates are in agreement with transition rates calculated from a model potential.

  19. Manipulation of the magnetron orbit of a positron cloud in a Penning trap

    SciTech Connect (OSTI)

    Mortensen, T.; Deller, A.; Isaac, C. A.; Werf, D. P. van der; Charlton, M. [Department of Physics, College of Science, Swansea University, Singleton Park, Swansea SA2 8PP (United Kingdom); Machacek, J. R. [Centre for Matter-Antimatter Studies, Physics Laboratories, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia)

    2013-01-15T23:59:59.000Z

    We describe a simple and versatile method to manipulate the amplitude of the magnetron orbit of ions stored in a Penning trap, applied here to a cloud of low energy positrons. By applying a pulsed voltage to a split electrode in the trap, which is normally used for rotating wall compression of the particles, the size of the magnetron orbit can be changed at will. The modified orbit has been shown to be stable for many magnetron periods. The technique could find use in applications which require off-axis ejection of particles, for instance in the filling of arrays of traps for multicell positron storage.

  20. Radial transport of energetic ions in the presence of trapped electron mode turbulence

    SciTech Connect (OSTI)

    Chowdhury, J.; Wang, W.; Ethier, S.; Manickam, J. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Ganesh, R. [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

    2011-11-15T23:59:59.000Z

    The nature of transport of hot ions is studied in the presence of microturbulence generated by the trapped electron mode in a Tokamak using massively parallel, first principle based global nonlinear gyrokinetic simulation, and with the help of a passive tracer method. Passing and trapped hot ions are observed to exhibit inverse and inverse square scaling with energy, while those with isotropic pitch distribution are found to exhibit inverse dependence on energy. For all types of hot ions, namely, isotropic, passing, and trapped, the radial transport appears to be subdiffusive for the parameters considered.

  1. Biexciton emission from single isoelectronic traps formed by nitrogen-nitrogen pairs in GaAs

    SciTech Connect (OSTI)

    Takamiya, Kengo; Fukushima, Toshiyuki; Yagi, Shuhei; Hijikata, Yasuto; Yaguchi, Hiroyuki [Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku , Saitama 338-8570 (Japan); Mochizuki, Toshimitsu; Yoshita, Masahiro; Akiyama, Hidefumi [Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan); Kuboya, Shigeyuki; Onabe, Kentaro [Department of Advanced Materials Science, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan); Katayama, Ryuji [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)

    2013-12-04T23:59:59.000Z

    We have studied photoluminescence (PL) from individual isoelectronic traps formed by nitrogen-nitrogen (NN) pairs in GaAs. Sharp emission lines due to exciton and biexciton were observed from individual isoelectronic traps in nitrogen atomic-layer doped (ALD) GaAs. The binding energy of biexciton bound to individual isoelectronic traps was approximately 8 meV. Both the exciton and biexciton luminescence lines show completely random polarization and no fine-structure splitting. These results are desirable to the application to the quantum cryptography used in the field of quantum information technology.

  2. Zurek-Kibble Mechanism for the Spontaneous Vortex Formation in Nb-Al/Al{sub ox}/Nb Josephson Tunnel Junctions: New Theory and Experiment

    SciTech Connect (OSTI)

    Monaco, R. [Istituto di Cibernetica del C.N.R., 80078, Pozzuoli (Italy) and Unita INFM-Dipartimento di Fisica, Universita di Salerno, 84081 Baronissi (Italy); Mygind, J.; Aaroe, M. [Department of Physics, B309, Technical University of Denmark, DK-2800 Lyngby (Denmark); Rivers, R.J. [Blackett Laboratory, Imperial College London, London SW7 2AZ (United Kingdom); Koshelets, V.P. [Institute of Radio Engineering and Electronics, Russian Academy of Science, Mokhovaya 11, Building 7, 125009, Moscow (Russian Federation)

    2006-05-12T23:59:59.000Z

    New scaling behavior has been both predicted and observed in the spontaneous production of fluxons in quenched Nb-Al/Al{sub ox}/Nb annular Josephson tunnel junctions (JTJs) as a function of the quench time, {tau}{sub Q}. The probability f{sub 1} to trap a single defect during the normal-metal-superconductor phase transition clearly follows an allometric dependence on {tau}{sub Q} with a scaling exponent {sigma}=0.5, as predicted from the Zurek-Kibble mechanism for realistic JTJs formed by strongly coupled superconductors. This definitive experiment replaces one reported by us earlier, in which an idealized model was used that predicted {sigma}=0.25, commensurate with the then much poorer data. Our experiment remains the only condensed matter experiment to date to have measured a scaling exponent with any reliability.

  3. Certification Framework Based on Effective Trapping for Geologic Carbon Sequestration

    SciTech Connect (OSTI)

    Oldenburg, Curtis M.; Bryant, Steven L.; Nicot, Jean-Philippe

    2009-01-15T23:59:59.000Z

    We have developed a certification framework (CF) for certifying the safety and effectiveness of geologic carbon sequestration (GCS) sites. Safety and effectiveness are achieved if CO{sub 2} and displaced brine have no significant impact on humans, other living things, resources, or the environment. In the CF, we relate effective trapping to CO{sub 2} leakage risk which takes into account both the impact and probability of leakage. We achieve simplicity in the CF by using (1) wells and faults as the potential leakage pathways, (2) compartments to represent environmental resources that may be impacted by leakage, (3) CO{sub 2} fluxes and concentrations in the compartments as proxies for impact to vulnerable entities, (4) broad ranges of storage formation properties to generate a catalog of simulated plume movements, and (5) probabilities of intersection of the CO{sub 2} plume with the conduits and compartments. We demonstrate the approach on a hypothetical GCS site in a Texas Gulf Coast saline formation. Through its generality and flexibility, the CF can contribute to the assessment of risk of CO{sub 2} and brine leakage as part of the certification process for licensing and permitting of GCS sites around the world regardless of the specific regulations in place in any given country.

  4. Operation of the Lower Granite Dam Adult Trap, 2008.

    SciTech Connect (OSTI)

    Harmon, Jerrel R.

    2009-01-01T23:59:59.000Z

    During 2008 we operated the adult salmonid trap at Lower Granite Dam from 7 March through 25 November, except during a short summer period when water temperatures were too high to safely handle fish. We collected and handled a total of 20,463 steelhead Oncorhynchus mykiss and radio-tagged 34 of the hatchery steelhead. We took scale samples from 3,724 spring/summer Chinook salmon O. tshawytscha for age and genetic analysis. We collected and handled a total of 8,254 fall Chinook salmon. Of those fish, 2,520 adults and 942 jacks were transported to Lyons Ferry Hatchery on the Snake River in Washington. In addition, 961 adults and 107 jacks were transported to the Nez Perce Tribal Hatchery on the Clearwater River in Idaho. The remaining 3,724 fall Chinook salmon were passed upstream. Scales samples were taken from 780 fall Chinook salmon tagged with passive integrated transponder (PIT) tags and collected by the sort-by-code system.

  5. Three-dimensional light trap for reflective particles

    DOE Patents [OSTI]

    Neal, Daniel R. (Tijeras, NM)

    1999-01-01T23:59:59.000Z

    A system for containing either a reflective particle or a particle having an index of refraction lower than that of the surrounding media in a three-dimensional light cage. A light beam from a single source illuminates an optics system and generates a set of at least three discrete focussed beams that emanate from a single exit aperture and focus on to a focal plane located close to the particle. The set of focal spots defines a ring that surrounds the particle. The set of focussed beams creates a "light cage" and circumscribes a zone of no light within which the particle lies. The surrounding beams apply constraining forces (created by radiation pressure) to the particle, thereby containing it in a three-dimensional force field trap. A diffractive element, such as an aperture multiplexed lens, or either a Dammann grating or phase element in combination with a focusing lens, may be used to generate the beams. A zoom lens may be used to adjust the size of the light cage, permitting particles of various sizes to be captured and contained.

  6. Particle trap for compressed gas insulated transmission systems

    DOE Patents [OSTI]

    Cookson, A.H.

    1984-04-26T23:59:59.000Z

    A particle trap is provided for gas insulated transmission lines having a central high voltage conductor supported within an outer coaxial conductive sheath by a dielectric support member. A cavity between the inner conductor and outer sheath is filled with a dielectric insulating gas. A cone-like particle deflector, mounted to the inner conductor, deflects moving particles away from the support member, to radially outer portions of the cavity. A conductive shield is disposed adjacent the outer sheath to form a field-free region in radially outer portions of the cavity, between the shield and the sheath. Particles traveling along the cavity are deflected by the cone-like deflector into the field-free region where they are held immobile. In a vertical embodiment, particles enter the field-free region through an upper end of a gap formed between shield and sheath members. In a horizontal embodiment, the deflector cone has a base which is terminated radially internally of the shield. Apertures in the shield located adjacent the deflector allow passage of deflected particles into the field-free region. The dielectric support member is thereby protected from contaminating particles that may otherwise come to rest thereon.

  7. Particle trap for compressed gas insulated transmission systems

    DOE Patents [OSTI]

    Cookson, Alan H. (Pittsburgh, PA)

    1985-01-01T23:59:59.000Z

    A particle trap is provided for gas insulated transmission lines having a central high voltage conductor supported within an outer coaxial conductive sheath by a dielectric support member. A cavity between the inner conductor and outer sheath is filled with a dielectric insulating gas. A cone-like particle deflector, mounted to the inner conductor, deflects moving particles away from the support member, to radially outer portions of the cavity. A conductive shield is disposed adjacent the outer sheath to form a field-free region in radially outer portions of the cavity, between the shield and the sheath. Particles traveling along the cavity are deflected by the cone-like deflector into the field-free region where they are held immobile. In a vertical embodiment, particles enter the field-free region through an upper end of a gap formed between shield and sheath members. In a horizontal embodiment, the deflector cone has a base which is terminated radially internally of the shield. Apertures in the shield located adjacent the deflector allow passage of deflected particles into the field-free region. The dielectric support member is thereby protected from contaminating particles that may otherwise come to rest thereon.

  8. Dynamical Friction and Resonance Trapping in Planetary Systems

    E-Print Network [OSTI]

    Nader Haghighipour

    1998-12-05T23:59:59.000Z

    A restricted planar circular three-body system, consisting of the Sun and two planets, is studied as a simple model for a planetary system. The mass of the inner planet is considered to be larger and the system is assumed to be moving in a uniform interplanetary medium with constant density. Numerical integrations of this system indicate a resonance capture when the dynamical friction of the interplanetary medium is taken into account. As a result of this resonance trapping, the ratio of orbital periods of the two planets becomes nearly commensurate and the eccentricity and semimajor axis of the orbit of the outer planet and also its angular momentum and total energy become constant. It appears from the numerical work that the resulting commensurability and also the resonant values of the orbital elements of the outer planet are essentially independent of the initial relative positions of the two bodies. The results of numerical integrations of this system are presented and the first-order partially averaged equations are studied in order to elucidate the behavior of the system while captured in resonance.

  9. Variable residence time vortex combustor

    DOE Patents [OSTI]

    Melconian, Jerry O. (76 Beaver Rd., Reading, MA 01867)

    1987-01-01T23:59:59.000Z

    A variable residence time vortex combustor including a primary combustion chamber for containing a combustion vortex, and a plurality of louvres peripherally disposed about the primary combustion chamber and longitudinally distributed along its primary axis. The louvres are inclined to impel air about the primary combustion chamber to cool its interior surfaces and to impel air inwardly to assist in driving the combustion vortex in a first rotational direction and to feed combustion in the primary combustion chamber. The vortex combustor also includes a second combustion chamber having a secondary zone and a narrowed waist region in the primary combustion chamber interconnecting the output of the primary combustion chamber with the secondary zone for passing only lower density particles and trapping higher density particles in the combustion vortex in the primary combustion chamber for substantial combustion.

  10. Maximization of permanent trapping of CO{sub 2} and co-contaminants in the highest-porosity formations of the Rock Springs Uplift (Southwest Wyoming): experimentation and multi-scale modeling

    SciTech Connect (OSTI)

    Piri, Mohammad

    2014-03-31T23:59:59.000Z

    Under this project, a multidisciplinary team of researchers at the University of Wyoming combined state-of-the-art experimental studies, numerical pore- and reservoir-scale modeling, and high performance computing to investigate trapping mechanisms relevant to geologic storage of mixed scCO{sub 2} in deep saline aquifers. The research included investigations in three fundamental areas: (i) the experimental determination of two-­?phase flow relative permeability functions, relative permeability hysteresis, and residual trapping under reservoir conditions for mixed scCO{sub 2}-­?brine systems; (ii) improved understanding of permanent trapping mechanisms; (iii) scientifically correct, fine grid numerical simulations of CO{sub 2} storage in deep saline aquifers taking into account the underlying rock heterogeneity. The specific activities included: (1) Measurement of reservoir-­?conditions drainage and imbibition relative permeabilities, irreducible brine and residual mixed scCO{sub 2} saturations, and relative permeability scanning curves (hysteresis) in rock samples from RSU; (2) Characterization of wettability through measurements of contact angles and interfacial tensions under reservoir conditions; (3) Development of physically-­?based dynamic core-­?scale pore network model; (4) Development of new, improved high-­? performance modules for the UW-­?team simulator to provide new capabilities to the existing model to include hysteresis in the relative permeability functions, geomechanical deformation and an equilibrium calculation (Both pore-­? and core-­?scale models were rigorously validated against well-­?characterized core-­? flooding experiments); and (5) An analysis of long term permanent trapping of mixed scCO{sub 2} through high-­?resolution numerical experiments and analytical solutions. The analysis takes into account formation heterogeneity, capillary trapping, and relative permeability hysteresis.

  11. Exciton trapping in vibrationally excited organic molecules near a ZnO surface

    E-Print Network [OSTI]

    Foglia, Laura; Wolf, Martin; Stähler, Julia

    2014-01-01T23:59:59.000Z

    We present a systematic study of the exciton population dynamics at the interface of the spirobifluorene derivative 2,7-bis(biphenyl-4-yl)-2',7'-ditertbutyl-9.9'-spirobifluorene (SP6) and the non-polar (10-10) surface of ZnO, using time-resolved excited state optical transmission spectroscopy. The photoexcited dye first undergoes intramolecular vibrational relaxation in the S1 state on a 2 to 9 ps timescale. Subsequently, the excited state transmission reveals transitions from two distinct vibrational levels of S1, with a lifetime of the vibrationally excited state that is comparable to the one of the vibrational ground state (vGS). The electronic population relaxes by (i) decay to the electronic ground state (ii) transfer to a long-lived dark state that remains populated for longer than 5 microseconds, and (iii) diffusion-limited charge transfer to the ZnO conduction band. Remarkably, the lifetime of the vibratioanlly trapped excition (exciton-vibron) and vGS exciton are not equally affected by a change of s...

  12. Overview of the current spectroscopy effort on the Livermore electron beam ion traps

    SciTech Connect (OSTI)

    Beiersdorfer, P.; Lopez-Urrutia, J.C. [Lawrence Livermore National Lab., CA (United States); Brown, G. [Auburn Univ., AL (United States)] [and others

    1995-06-29T23:59:59.000Z

    An overview is given of the current spectroscopic effort on the Livermore electron beam ion trap facilities. The effort focuses on four aspects: spectral line position, line intensity, temporal evolution, and line shape. Examples of line position measurements include studies of the K-shell transitions in heliumlike Kr{sup 34+} and the 2s-2p intrashell transitions in lithiumlike Th{sup 87+} and U{sup 89+}, which provide benchmark values for testing the theory of relativistic and quantum electrodynamical contributions in high-Z ions. Examples of line intensity measurements are provided by measurements of the electron-impact excitation and dielectronic recombination cross sections of heliumlike transition-metal ions Ti{sup 20+} through CO{sup 25+}. A discussion of radiative lifetime measurements of metastable levels in heliumlike ions is given to illustrate the time-resolved spectroscopy techniques in the microsecond range. The authors also present a measurement of the spectral lineshape that illustrates the very low ion temperatures that can be achieved in an EBIT.

  13. Trapping and Assembly of Living Colloids at Water/Water Interfaces

    E-Print Network [OSTI]

    Sarah D. Hann; Mark Goulian; Daeyeon Lee; Kathleen J. Stebe

    2014-12-11T23:59:59.000Z

    We study the assembly of colloids in a two phase water-water system that provides an environment that can sustain bacteria, providing a new structure with rich potential to confine and structure living colloids. The water-water system, formed via phase separation of a casein and xanthan mixture, forms a 3-D structure of coexisting casein-rich and xanthan-rich phases. Fluorescent labelling and confocal microscopy reveal the attachment of these living colloids, including Escherichia coli and Pseudomonas aeruginosa, at the interface between the two phases. Inert colloids also become trapped at the interfaces, suggesting that the observed attachment can be attributed to capillarity. Over time, these structures coarsen and eventually degrade, illustrating the dynamic nature of these systems. This system lays the foundation for future studies of the interplay of physicochemical properties of the fluid interfaces and bulk phases and microbial responses they provoke to induce complex spatial organization, to study species which occupy distinct niches, and to optimize efficient microbial cross-feeding or protection from competitors.

  14. Simulator of the elementary evolution operator with the motional states of an ion in an anharmonic trap

    E-Print Network [OSTI]

    Ludovic Santos; Yves Justum; Nathalie Vaeck; M. Desouter-Lecomte

    2015-01-10T23:59:59.000Z

    Following a recent proposal of L. Wang and D. Babikov, J. Chem. Phys. 137, 064301 (2012), we theoretically illustrate the possibility of using the motional states of a $Cd^+$ ion trapped in a slightly anharmonic potential to realize a quantum dynamics simulator of a single-particle time-dependent Schr\\"odinger equation. The simulated wave packet is discretized on a spatial grid and the grid points are mapped on the ion motional states which define the qubit network. The localization probability at each grid point is obtained from the population in the corresponding motional state. The quantum gate is the elementary evolution operator corresponding to the time dependant Schr\\"odinger equation of the simulated system. The corresponding matrix can be estimated by any numerical algorithm. The radio-frequency field able to drive this unitary transformation among the qubit states of the ion is obtained by multi target optimal control theory. The ion is assumed to be cooled in the ground motional state 1and the preliminary step consists in initializing the qubits with the amplitudes of the initial simulated wave packet. Then the time evolution of the localization probability at the grids points is obtained by successive applications of the gate and reading out the motional state population. The gate field is unique for a given simulated potential. Only the field preparing the initial wave packet has to be optimized for different simulations. We check the stability of the simulation against decoherence due to fluctuating electric fields in the trap electrodes by a dissipative Lindblad dynamics.

  15. Simulation of the elementary evolution operator with the motional states of an ion in an anharmonic trap

    E-Print Network [OSTI]

    Ludovic Santos; Yves Justum; Nathalie Vaeck; M. Desouter-Lecomte

    2015-03-03T23:59:59.000Z

    Following a recent proposal of L. Wang and D. Babikov, J. Chem. Phys. 137, 064301 (2012), we theoretically illustrate the possibility of using the motional states of a $Cd^+$ ion trapped in a slightly anharmonic potential to simulate the single-particle time-dependent Schr\\"odinger equation. The simulated wave packet is discretized on a spatial grid and the grid points are mapped on the ion motional states which define the qubit network. The localization probability at each grid point is obtained from the population in the corresponding motional state. The quantum gate is the elementary evolution operator corresponding to the time-dependent Schr\\"odinger equation of the simulated system. The corresponding matrix can be estimated by any numerical algorithm. The radio-frequency field able to drive this unitary transformation among the qubit states of the ion is obtained by multi-target optimal control theory. The ion is assumed to be cooled in the ground motional state and the preliminary step consists in initializing the qubits with the amplitudes of the initial simulated wave packet. The time evolution of the localization probability at the grids points is then obtained by successive applications of the gate and reading out the motional state population. The gate field is always identical for a given simulated potential, only the field preparing the initial wave packet has to be optimized for different simulations. We check the stability of the simulation against decoherence due to fluctuating electric fields in the trap electrodes by applying dissipative Lindblad dynamics.

  16. An injection-locked 674 nm laser for Strontium-88 ion trapping

    E-Print Network [OSTI]

    Katz, Rena J. (Rena Jenelle)

    2012-01-01T23:59:59.000Z

    Energy levels of the valence electron of a single trapped ??Sr+ ion can be harnessed as an effective qubit for quantum information processing. The qubit transition to a metastable energy state can be stimulated by a laser ...

  17. WAVELENGTH DEPENDENT EFFECTIVE TRAP DENSITY IN CdTe : EVIDENCE FOR THE PRESENCE OF TWO

    E-Print Network [OSTI]

    1 WAVELENGTH DEPENDENT EFFECTIVE TRAP DENSITY IN CdTe : EVIDENCE FOR THE PRESENCE OF TWO.1016/S0030-4018(96)00516-0 #12;2 Photorefractive semiconductors like CdTe are characterized by a low

  18. Coastal Trapped Waves Generated By Hurricane Andrew on the Texas-Louisiana Shelf

    E-Print Network [OSTI]

    Pearce, Stuart

    2012-02-14T23:59:59.000Z

    in observations as far south as Port Isabel, Texas. The prominent frequencies determined from wavelet analysis are compared with predicted coastal trapped wave dispersion modes and show good agreement in the predicted group speed and cross-shelf structure...

  19. Vertically aligned gas-insulated transmission line having particle traps at the inner conductor

    DOE Patents [OSTI]

    Dale, Steinar J. (Monroeville, PA)

    1984-01-01T23:59:59.000Z

    Gas insulated electrical apparatus having first and second conductors separated by an insulating support within an insulating gas environment, and particle traps disposed along the surface of the high potential conductor for trapping and inactivating foreign particles which may be present within the insulating gas medium. Several embodiments of the invention were developed which are particularly suited for vertically aligned gas insulated transmission lines. The particle traps are grooves or cavities formed into the walls of the tubular inner conductor, without extending into the hollow portion of the conductor. In other embodiments, the traps are appendages or insert flanges extending from the inner conductor, with the insulator supports contacting the appendages instead of the inner conductor.

  20. E-Print Network 3.0 - atom traps atomic Sample Search Results

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

    for: atom traps atomic Page: << < 1 2 3 4 5 > >> 1 An output coupler for Bose condensed atoms The observations of BEC have stimulated interest in atom lasers, coherent sources of...

  1. Destabilization of low-n peeling modes by trapped energetic particles

    SciTech Connect (OSTI)

    Hao, G. Z.; Wang, A. K.; Mou, Z. Z.; Qiu, X. M. [Southwestern Institute of Physics, PO Box 432, Chengdu 610041 (China)] [Southwestern Institute of Physics, PO Box 432, Chengdu 610041 (China); Liu, Y. Q. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom)] [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Matsunaga, G. [Japan Atomic Energy Agency, 801-1, Mukouyama, Naka, Ibaraki 311-0193 (Japan)] [Japan Atomic Energy Agency, 801-1, Mukouyama, Naka, Ibaraki 311-0193 (Japan); Okabayashi, M. [Princeton Plasma Physics Laboratory, PO Box 451, Princeton, New Jersey 08543-0451 (United States)] [Princeton Plasma Physics Laboratory, PO Box 451, Princeton, New Jersey 08543-0451 (United States)

    2013-06-15T23:59:59.000Z

    The kinetic effect of trapped energetic particles (EPs), arising from perpendicular neutral beam injection, on the stable low-n peeling modes in tokamak plasmas is investigated, through numerical solution of the mode's dispersion relation derived from an energy principle. A resistive-wall peeling mode with m/n=6/1, with m and n being the poloidal and toroidal mode numbers, respectively, is destabilized by trapped EPs as the EPs' pressure exceeds a critical value ?{sub c}{sup *}, which is sensitive to the pitch angle of trapped EPs. The dependence of ?{sub c}{sup *} on the particle pitch angle is eventually determined by the bounce average of the mode eigenfunction. Peeling modes with higher m and n numbers can also be destabilized by trapped EPs. Depending on the wall distance, either a resistive-wall peeling mode or an ideal-kink peeling mode can be destabilized by EPs.

  2. Poly(vinyl alcohol)-based buffering membranes for isoelectric trapping separations

    E-Print Network [OSTI]

    Craver, Helen C.

    2009-05-15T23:59:59.000Z

    Isoelectric trapping (IET) in multicompartment electrolyzers (MCE) has been widely used for the electrophoretic separation of ampholytic compounds such as proteins. In IET, the separation occurs in the buffering membranes that form a step-wise p...

  3. Phase-slippage and self-trapping in a self-induced bosonic Josephson junction

    E-Print Network [OSTI]

    Abad, M; Mayol, R; Pi, M; Jezek, D M

    2011-01-01T23:59:59.000Z

    A dipolar condensate confined in a toroidal trap constitutes a self-induced Josepshon junction when the dipoles are oriented perpendicularly to the trap symmetry axis and the s-wave scattering length is small enough. The ring-shaped double-well potential coming from the anisotropic character of the mean-field dipolar interaction is robust enough to sustain self-trapping dynamics, which takes place when the initial population imbalance between the two wells is large. We show that in this system the self-trapping regime is directly related to a vortex-induced phase-slip dynamics. A vortex and antivortex are spontaneously nucleated in the low density regions, before a minimum of the population imbalance is reached, and then cross the toroidal section in opposite directions through the junctions.This vortex dynamics yields a phase slip between the two weakly linked condensates causing an inversion of the particle flux.

  4. Neutral carbohydrate geochemistry of particulate material (trap and core sediments) in an eutrophic lake (Aydat,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Neutral carbohydrate geochemistry of particulate material (trap and core sediments) in an eutrophic Carbohydrate compositions were determined on sinking particles and core samples from eutrophic lake Aydat; Eutrophic lake; Aydat lake 1. Introduction Polysaccharides are common structural and storage polymers

  5. Molecular-bond hardening and dynamics of molecular stabilization and trapping in intense laser pulses

    E-Print Network [OSTI]

    Yao, Guanhua; Chu, Shih-I

    1993-07-01T23:59:59.000Z

    stabilization and population trapping of high-lying vibrational states and chemical bond hardening are predicted for both continuous-wave (cw) lasers and short laser pulses. While the intensity dependences of the laser-induced stabilization are essentially...

  6. Engineering optical traps for new environments and applications in the measurement of biological adhesives and motors

    E-Print Network [OSTI]

    Appleyard, David Collins

    2009-01-01T23:59:59.000Z

    Optical traps have played a central role in the exploration of biological systems through the examination of molecular motors, biopolymers, and many other interactions at the nano and micro length scales. This thesis seeks ...

  7. Depletion, quantum jumps, and temperature measurements of ??Sr? ions in a linear Paul Trap

    E-Print Network [OSTI]

    Richerme, Philip J

    2006-01-01T23:59:59.000Z

    This thesis describes the design and construction of two laser systems to probe the 674nm transition of ??Sr? ions in a linear Paul trap. The first laser system made use of a molecular transition in Iodine to stabilize the ...

  8. Technological assessment of light-trapping technology for thin-film Si solar cell

    E-Print Network [OSTI]

    Susantyoko, Rahmat Agung

    2009-01-01T23:59:59.000Z

    The proposed light trapping technology of Distributed Bragg Reflector (DBR) with Diffraction Grating (DG) and Anti-Reflection Coating (ARC) for thin film Si solar cell was analyzed from the technology, market, and ...

  9. Light trapping in thin film solar cells using textured photonic crystal

    DOE Patents [OSTI]

    Yi, Yasha (Somerville, MA); Kimerling, Lionel C. (Concord, MA); Duan, Xiaoman (Amesbury, MA); Zeng, Lirong (Cambridge, MA)

    2009-01-27T23:59:59.000Z

    A solar cell includes a photoactive region that receives light. A photonic crystal is coupled to the photoactive region, wherein the photonic crystal comprises a distributed Bragg reflector (DBR) for trapping the light.

  10. Combining Low-Temperature Combustion with Lean-NOx Trap Yields...

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

    and Posters 2005deerhuff.pdf More Documents & Publications Intra-catalyst Reductant Chemistry in Lean NOx Traps: A Study on Sulfur Effects Reductant Utilization in a LNT + SCR...

  11. Intra-catalyst Reductant Chemistry in Lean NOx Traps: A Study...

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

    Intra-catalyst Reductant Chemistry in Lean NOx Traps: A Study on Sulfur Effects Jim Parks (parksjeii@ornl.gov), Matt Swartz, Shean Huff, Brian West Oak Ridge National Laboratory...

  12. EXPERIMENTAL RESULTS ON TRAPPING A GUN PLASMA IN TORMAC P-l

    E-Print Network [OSTI]

    Pincosy, P.A.

    2012-01-01T23:59:59.000Z

    P.A. Pincosy, A Toroidal Plasma Gun, 11 LBL-9507, (1979),RESULTS ON TRAPPING A GUN PLASMA IN TORMAC P-~1* P. A.further work on the higher gun p13sma energy may lead to

  13. Study of electron trapping by a transversely ellipsoidal bubble in the laser wake-field acceleration

    SciTech Connect (OSTI)

    Cho, Myung-Hoon [School of Natural Science, UNIST, BanYeon-Ri 100, Ulju-gun, Ulsan 689-798 (Korea, Republic of)] [School of Natural Science, UNIST, BanYeon-Ri 100, Ulju-gun, Ulsan 689-798 (Korea, Republic of); Kim, Young-Kuk; Hur, Min Sup [School of Electrical and Computer Engineering, UNIST, BanYeon-Ri 100, Ulju-gun, Ulsan 689-798 (Korea, Republic of)] [School of Electrical and Computer Engineering, UNIST, BanYeon-Ri 100, Ulju-gun, Ulsan 689-798 (Korea, Republic of)

    2013-09-15T23:59:59.000Z

    We present electron trapping in an ellipsoidal bubble which is not well explained by the spherical bubble model by [Kostyukov et al., Phys. Rev. Lett. 103, 175003 (2009)]. The formation of an ellipsoidal bubble, which is elongated transversely, frequently occurs when the spot size of the laser pulse is large compared to the plasma wavelength. First, we introduce the relation between the bubble size and the field slope inside the bubble in longitudinal and transverse directions. Then, we provide an ellipsoidal model of the bubble potential and investigate the electron trapping condition by numerical integration of the equations of motion. We found that the ellipsoidal model gives a significantly less restrictive trapping condition than that of the spherical bubble model. The trapping condition is compared with three-dimensional particle-in-cell simulations and the electron trajectory in test potential simulations.

  14. Phase slippage and self-trapping in a self-induced bosonic Josephson junction

    SciTech Connect (OSTI)

    Abad, M.; Guilleumas, M.; Mayol, R.; Pi, M. [Departament d'Estructura i Constituents de la Materia, Facultat de Fisica, Universitat de Barcelona, E-08028 Barcelona (Spain); Jezek, D. M. [IFIBA-CONICET and Departamento de Fisica, FCEN-UBA Pabellon 1, Ciudad Universitaria, 1428 Buenos Aires (Argentina)

    2011-09-15T23:59:59.000Z

    A dipolar condensate confined in a toroidal trap constitutes a self-induced Josephson junction when the dipoles are oriented perpendicularly to the trap symmetry axis and the s-wave scattering length is small enough. The ring-shaped double-well potential coming from the anisotropic character of the mean-field dipolar interaction is robust enough to sustain self-trapping dynamics, which takes place when the initial population imbalance between the two wells is large. We show that, in this system, the self-trapping regime is directly related to a vortex-induced phase-slip dynamics. A vortex and antivortex are spontaneously nucleated in the low-density regions before a minimum of the population imbalance is reached and then cross the toroidal section in opposite directions through the junctions. This vortex dynamics yields a phase slip between the two weakly linked condensates causing an inversion of the particle flux.

  15. Situ Discovery Electrostatic Potential, Trapping Electrons and Mediating Fast Reconnection Earth's Magnetotail

    E-Print Network [OSTI]

    Egedal, Jan

    Situ Discovery Electrostatic Potential, Trapping Electrons and Mediating Fast Reconnection Earth phase distributions, measured Wind spacecraft a rare crossing diffusion region in Earth's magnetotail, the presence a strong electrostatic potential within ion diffusion region is revealed. potential reaching

  16. High-Q superconducting coplanar waveguide resonators for integration into molecule ion traps

    E-Print Network [OSTI]

    McCaughan, Adam Nykoruk

    2010-01-01T23:59:59.000Z

    Over the last decade, quantum information experiments with trapped ions have demonstrated essential steps towards quantum computing and quantum simulation. Large fields are required to achieve strong coupling to the ions ...

  17. Emittance and Current of Electrons Trapped in a Plasma Wakefield Accelerator

    SciTech Connect (OSTI)

    Kirby, N; Blumenfeld, I; Clayton, C.E.; Decker, F.J.; Hogan, M.J.; Huang, C.; Ischebeck, R.; Iverson, R.H.; Joshi, C.; Katsouleas, T.; Lu, W.; Marsh, K.A.; Mori, W.B.; Muggli, P; Oz, E.; Siemann, R.H.; Walz, D.R.; Zhou, M.; /SLAC /UCLA /USC

    2008-09-24T23:59:59.000Z

    In recent experiments plasma electrons became trapped in a plasma wakefield accelerator (PWFA). The transverse size of these trapped electrons on a downstream diagnostic yields an upper limit measurement of transverse normalized emittance divided by peak current, {var_epsilon}{sub N,x}/I. The lowest upper limit for {var_epsilon}{sub N,x}/I measured in the experiment is 1.3 {center_dot} 10{sup -10} m/A.

  18. Extending Penning trap mass measurements with SHIPTRAP to the heaviest elements

    SciTech Connect (OSTI)

    Block, M.; Ackermann, D.; Herfurth, F.; Hofmann, S. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Blaum, K. [Max-Planck-Institut fuer Kernphysik, 69117 Heidelberg, Germany and Ruprecht-Karls-Universitaet, 69120 Heidelberg (Germany); Droese, C.; Marx, G.; Schweikhard, L. [Ernst-Moritz-Arndt-Universitaet, 17487 Greifswald (Germany); Duellmann, Ch. E. [Johannes Gutenberg-Universitaet, 55099 Mainz, Germany and GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, 64291 Darmstadt, Germany and Helmholtz-Institut Mainz, 55099 Mainz (Germany); Eibach, M. [Ruprecht-Karls-Universitaet, 69120 Heidelberg, Germany and Johannes Gutenberg-Universitaet, 55099 Mainz (Germany); Eliseev, S. [Max-Planck-Institut fuer Kernphysik, 69117 Heidelberg (Germany); Haettner, E.; Plass, W. R.; Scheidenberger, C. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, 64291 Darmstadt, Germany and Justus-Liebig-Universitaet, 35392 Giessen (Germany); Hessberger, F. P. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, 64291 Darmstadt, Germany and Helmholtz-Institut Mainz, 55099 Mainz (Germany); Ramirez, E. Minaya [Helmholtz-Institut Mainz, 55099 Mainz, Germany and GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Nesterenko, D. [Petersburg Nuclear Physics Institute, Gatchina, 188300 St. Petersburg (Russian Federation); and others

    2013-03-19T23:59:59.000Z

    Penning-trap mass spectrometry of radionuclides provides accurate mass values and absolute binding energies. Such mass measurements are sensitive indicators of the nuclear structure evolution far away from stability. Recently, direct mass measurements have been extended to the heavy elements nobelium (Z=102) and lawrencium (Z=103) with the Penning-trap mass spectrometer SHIPTRAP. The results probe nuclear shell effects at N=152. New developments will pave the way to access even heavier nuclides.

  19. Computation of the Field in an Axial Gap, Trapped-Flux Type Superconducting Electric Machine

    E-Print Network [OSTI]

    Shen, Zejun; Ainslie, Mark D.; Campbell, Archie M.; Cardwell, David A.

    2014-11-04T23:59:59.000Z

    Abstract—The Bulk Superconductivity Group at the University of Cambridge is currently investigating the use of high temper- ature superconductors in wire and bulk form to increase the electrical and magnetic loading of an axial gap, trapped flux... electric machines are an importantapplication of superconducting materials in both bulk and wire forms. Bulk high temperature superconductors, in partic- ular, are capable of trapping magnetic fields greater than 17 T below 30 K [1], [2], as well as up to 3...

  20. Laser cooling and sympathetic cooling in a linear quadrupole rf trap

    E-Print Network [OSTI]

    Ryjkov, Vladimir Leonidovich

    2005-02-17T23:59:59.000Z

    LASER COOLING AND SYMPATHETIC COOLING IN A LINEAR QUADRUPOLE RF TRAP A Dissertation by VLADIMIR LEONIDOVICH RYJKOV Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree... of DOCTOR OF PHILOSOPHY December 2003 Major Subject: Physics LASER COOLING AND SYMPATHETIC COOLING IN A LINEAR QUADRUPOLE RF TRAP A Dissertation by VLADIMIR LEONIDOVICH RYJKOV Submitted to Texas A&M University in partial fulfillment of the requirements...