Sample records for lava flows trap

  1. Initial advance of long lava flows in open channels Daisuke Takagi, Herbert E. Huppert

    E-Print Network [OSTI]

    Huppert, Herbert

    cooling-limited when it reaches a maximum length attainable for a given supply of lava from the vent to cooling become important. Theoretical results are applied to the study of long lava flows that descended the dynamic properties of the bulk flow. In contrast, effects due to cooling played a major role throughout

  2. Plio-Pleistocene time-averaged field in southern Patagonia recorded in lava flows

    E-Print Network [OSTI]

    Singer, Bradley S.

    Plio-Pleistocene time-averaged field in southern Patagonia recorded in lava flows V. Mejia and N. D of 53 lava flows from southern Patagonia (latitudes 49.5°­52.1°S) that include the Pali-Aike volcanic, 7 figures, 3 tables. Keywords: paleomagnetic secular variation; Patagonia; Pali-Aike Volcanic Field

  3. Using infrared satellite data to drive a thermo-rheological/stochastic lava flow emplacement model: A method for near-real-time volcanic

    E-Print Network [OSTI]

    Wright, Robert

    Using infrared satellite data to drive a thermo-rheological/stochastic lava flow emplacement model the downhill paths that a lava flow could possibly follow and a thermorheological model to terminate, and A. J. L. Harris (2008), Using infrared satellite data to drive a thermo-rheological/stochastic lava

  4. 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.

  5. 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...

  6. Can aerosols be trapped in open flows?

    E-Print Network [OSTI]

    Rafael D. Vilela; Adilson E. Motter

    2008-01-22T23:59:59.000Z

    The fate of aerosols in open flows is relevant in a variety of physical contexts. Previous results are consistent with the assumption that such finite-size particles always escape in open chaotic advection. Here we show that a different behavior is possible. We analyze the dynamics of aerosols both in the absence and presence of gravitational effects, and both when the dynamics of the fluid particles is hyperbolic and nonhyperbolic. Permanent trapping of aerosols much heavier than the advecting fluid is shown to occur in all these cases. This phenomenon is determined by the occurrence of multiple vortices in the flow and is predicted to happen for realistic particle-fluid density ratios.

  7. NEW MEXICO BUREAU OF GEOLOGY & MINERAL RESOURCES, BULLETIN 160, 2004 Cosmogenic 36Cl ages of lava flows in the ZuniBandera

    E-Print Network [OSTI]

    Dunbar, Nelia W.

    309 NEW MEXICO BUREAU OF GEOLOGY & MINERAL RESOURCES, BULLETIN 160, 2004 Cosmogenic 36Cl ages of lava flows in the Zuni­Bandera volcanic field, northcentral New Mexico, U.S.A. Nelia W. Dunbar1 and Fred M. Phillips2 1New Mexico Bureau of Geology and Mineral Resources, New Mexico Institute of Mining

  8. Ancient Lava Flows Trap CO2 for Long-Term Storage in Big Sky Injection |

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: The Future of1Albuquerque, NMPerformanceof Energy4 * August 2004Anatomy of

  9. How many paleointensity determinations are required from a single lava flow to constitute a reliable average?

    E-Print Network [OSTI]

    Utrecht, Universiteit

    is currently the norm in order to ensure that the calculated mean paleointensity does not differ significantly from the true flow mean. Furthermore, they indicate that a low measured dispersion for a small number flows to avoid biasing of the mean. INDEX TERMS: 1533 Geomagnetism and Paleomagnetism: Remagnetization

  10. 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.

  11. 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.

  12. Visualizing multiphase flow and trapped fluid configurations in a model three-dimensional porous medium

    E-Print Network [OSTI]

    Amber T. Krummel; Sujit S. Datta; Stefan Mnster; David A. Weitz

    2013-01-21T23:59:59.000Z

    We report an approach to fully visualize the flow of two immiscible fluids through a model three-dimensional (3D) porous medium at pore-scale resolution. Using confocal microscopy, we directly image the drainage of the medium by the non-wetting oil and subsequent imbibition by the wetting fluid. During imbibition, the wetting fluid pinches off threads of oil in the narrow crevices of the medium, forming disconnected oil ganglia. Some of these ganglia remain trapped within the medium. By resolving the full 3D structure of the trapped ganglia, we show that the typical ganglion size, and the total amount of residual oil, decreases as the capillary number Ca increases; this behavior reflects the competition between the viscous pressure in the wetting fluid and the capillary pressure required to force oil through the pores of the medium. This work thus shows how pore-scale fluid dynamics influence the trapped fluid configurations in multiphase flow through 3D porous media.

  13. Peak discharge of a Pleistocene lava-dam outburst flood in Grand Canyon, Arizona, USA

    E-Print Network [OSTI]

    Received 6 May 2005 Availble online 7 February 2006 Abstract The failure of a lava dam 165,000 yr ago dam-failure and unsteady flow modeling to estimate a peak discharge and flow hydrograph. FailurePeak discharge of a Pleistocene lava-dam outburst flood in Grand Canyon, Arizona, USA Cassandra R

  14. Diesel particulate trap protection against uncontrolled regeneration via selective flow modulation

    SciTech Connect (OSTI)

    Pattas, K.; Samaras, Z.; Kyriakis, N.; Mihaildis, A.; Manikas, T. [Aristotle Univ. of Thessaloniki (Greece)

    1996-09-01T23:59:59.000Z

    Possible techniques to protect the filter against a failure scenario, so far reported, include filter by-passing and limiting the engine A/F ratio. Both techniques aim at controlling the oxygen content of the exhaust gas and thus reducing the oxidation rate in the filter. In this paper a new method for the protection of the trap is presented. This method, called Selective Flow Modulation (SFM) aims at controlling the reaction rate via the modulation of the exhaust gas flow through the filter. For the practical application of such a method, it is necessary to split the filter into at least two parts and to use at least one device for the flow modulation. In addition, a number of different possible SFM configurations are presented and their characteristics are analyzed together with the experimental results of the technique applied on two engines, one heavy and one light duty.

  15. 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.

  16. Cooling rate of some active lavas determined using an orbital imaging spectrometer

    E-Print Network [OSTI]

    Wright, Robert

    Click Here for Full Article Cooling rate of some active lavas determined using an orbital imaging flow is an important physical property to measure. Through its influence on lava crystallinity, cooling modeling problem that will aid in the analysis of data acquired by future hyperspectral remote sensing

  17. 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 ...

  18. 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

  19. Microfabricated Renewable Beads-Trapping/Releasing Flow Cell for Rapid Antigen-Antibody Reaction in Chemiluminescent Immunoassay

    SciTech Connect (OSTI)

    Fu, Zhifeng; Shao, Guocheng; Wang, Jun; Lu, Donglai; Wang, Wanjun; Lin, Yuehe

    2011-04-01T23:59:59.000Z

    A filter pillar-array microstructure was coupled with a pneumatic micro-valve to fabricate a reusable miniaturized beads-trapping/releasing flow cell, in which trapping and releasing beads can be conveniently realized by switching the micro-valve. This miniaturized device was suitable to construct automatic fluidic system for renewable surface analysis. The renewable surface strategy based on pneumatic micro-valve enabled capture of beads in beads chamber prior to each assay, and release of the used beads after the assay. Chemiluminescent competitive immunoassay of 3,5,6-trichloropyridinol (TCP) was performed as a model to demonstrate the application potential of this reusable miniaturized flow cell. The whole fluidic assay process including beads trapping, immuno-binding, beads washing, beads releasing and signal collection could be completed in 10 min. Immunoassay of TCP using this miniaturized device showed a linear range of 0.20-70 ng/mL with a limit of detection of 0.080 ng/mL. The device had been successfully used for detection of TCP spiked in rat serum with average recovery of 97%. This investigation provides a rapid, sensitive, reusable, low-cost and automatic miniaturized device for solid-phase biochemical analysis for various purposes.

  20. Idaho_LavaHotSprings

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh School footballHydrogenIT |Hot Springs Site #0104 Latitude: N. Lava

  1. Impact of background flow on dissolution trapping of carbon dioxide injected into saline aquifers

    E-Print Network [OSTI]

    Rapaka, Saikiran

    2011-01-01T23:59:59.000Z

    While there has been a large interest in studying the role of dissolution-driven free convection in the context of geological sequestration, the contribution of forced convection has been largely ignored. This manuscript considers CO$_2$ sequestration in saline aquifers with natural background flow and uses theoretical arguments to compute the critical background velocity needed to establish the forced convective regime. The theoretical arguments are supported by two dimensional high-resolution numerical simulations which demonstrate the importance of forced convection in enhancing dissolution in aquifers characterised by low Rayleigh numbers.

  2. Development of a Digital Fringe Projection Technique to Characterize the Transient Behavior of Wind-Driven Droplet/Rivulet Flows

    E-Print Network [OSTI]

    Hu, Hui

    endeavor, including lava flows in geology, tertiary oil recovery, lubricant oil films in tribology, surface and environmental problems ranging from microchip manufacturing, structured packing to lava flows in geology

  3. LAVA (Los Alamos Vulnerability and Risk Assessment Methodology): A conceptual framework for automated risk analysis

    SciTech Connect (OSTI)

    Smith, S.T.; Lim, J.J.; Phillips, J.R.; Tisinger, R.M.; Brown, D.C.; FitzGerald, P.D.

    1986-01-01T23:59:59.000Z

    At Los Alamos National Laboratory, we have developed an original methodology for performing risk analyses on subject systems characterized by a general set of asset categories, a general spectrum of threats, a definable system-specific set of safeguards protecting the assets from the threats, and a general set of outcomes resulting from threats exploiting weaknesses in the safeguards system. The Los Alamos Vulnerability and Risk Assessment Methodology (LAVA) models complex systems having large amounts of ''soft'' information about both the system itself and occurrences related to the system. Its structure lends itself well to automation on a portable computer, making it possible to analyze numerous similar but geographically separated installations consistently and in as much depth as the subject system warrants. LAVA is based on hierarchical systems theory, event trees, fuzzy sets, natural-language processing, decision theory, and utility theory. LAVA's framework is a hierarchical set of fuzzy event trees that relate the results of several embedded (or sub-) analyses: a vulnerability assessment providing information about the presence and efficacy of system safeguards, a threat analysis providing information about static (background) and dynamic (changing) threat components coupled with an analysis of asset ''attractiveness'' to the dynamic threat, and a consequence analysis providing information about the outcome spectrum's severity measures and impact values. By using LAVA, we have modeled our widely used computer security application as well as LAVA/CS systems for physical protection, transborder data flow, contract awards, and property management. It is presently being applied for modeling risk management in embedded systems, survivability systems, and weapons systems security. LAVA is especially effective in modeling subject systems that include a large human component.

  4. Cooling of Kilauea Iki lava lake

    SciTech Connect (OSTI)

    Hills, R.G.

    1982-02-01T23:59:59.000Z

    In 1959 Kilauea Iki erupted leaving a 110 to 120 m lake of molten lava in its crater. The resulting lava lake has provided a unique opportunity to study the cooling dynamics of a molten body and its associated hydrothermal system. Field measurements taken at Kilauea Iki indicate that the hydrothermal system above the cooling magma body goes through several stages, some of which are well modeled analytically. Field measurements also indicate that during most of the solidification period of the lake, cooling from above is controlled by 2-phase convection while conduction dominates the cooling of the lake from below. A summary of the field work related to the study of the cooling dynamics of Kilauea Iki is presented. Quantitative and qualitative cooling models for the lake are discussed.

  5. 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.

  6. Analytical-Numerical Modeling Of Komatiite Lava Emplacement And...

    Open Energy Info (EERE)

    Modeling Of Komatiite Lava Emplacement And Thermal Erosion At Perseverance, Western Australia Jump to: navigation, search OpenEI Reference LibraryAdd to library...

  7. Seismic Structure And Seismicity Of The Cooling Lava Lake Of...

    Open Energy Info (EERE)

    Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Seismic Structure And Seismicity Of The Cooling Lava Lake Of Kilauea Iki, Hawaii Abstract The...

  8. Managing the Steam Trap Population

    E-Print Network [OSTI]

    Atlas, R. D.

    1983-01-01T23:59:59.000Z

    item? .However, some converts to the gospel of enlighten ed steam trap management expect to achieve the following benefits: A 95% trap performance level which is a better than 30% improvement over the industry norm. Plus, we have found a well... trained. This may six surveys per year with a guaf'8nteed performance level involve two days of training per man including of better than 9596. This program usually has the best cash classroom and field instruction plus periodic flow, and faster...

  9. Site name: Khorgo Lava Pine, Mongolia Collectors: A. Hessl, N. Pederson, Kevin Anchukaitis, John Burkhart,

    E-Print Network [OSTI]

    Pederson, Neil

    Site name: Khorgo Lava Pine, Mongolia Collectors: A. Hessl, N. Pederson Empire, and modern Mongolia. Proceedings of the National Academy of Science collected in 2010 and 2012 across the Khorgo lava field near Tariat, Mongolia

  10. Basics of lava-lamp convection Balzs Gyre1

    E-Print Network [OSTI]

    Jnosi, Imre M.

    marketed only since the sixties 1 . The most essential ingredients are two immis- cible fluids of densities function, the lava lamp has been used also as visual aid in geoscience courses 2 demonstrat- ing phenomena such as the transformation of energy, force and motion, adiabatic circulations in the atmosphere and oceans, or magma

  11. Helium isotopes in historical lavas from Mount Vesuvius Comment on `Noble gas isotopic ratios from historical lavas

    E-Print Network [OSTI]

    Graham, David W.

    Discussion Helium isotopes in historical lavas from Mount Vesuvius Comment on `Noble gas isotopic. Introduction Helium isotope results recently published by Tedesco et al. [1] appear to show a decrease in 3 He. Results Helium isotope results from our laboratory are reported in Table 1. The 3 He/4 He ratio has been

  12. 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.

  13. Interaction of trapped ions with trapped atoms

    E-Print Network [OSTI]

    Grier, Andrew T. (Andrew Todd)

    2011-01-01T23:59:59.000Z

    In this thesis, I present results from two Paul-trap based ion traps carried out in the Vuleti? laboratory: the Atom-Ion trap for collision studies between cold atoms and cold ions, and the Cavity-Array trap for studying ...

  14. Porosity, Permeability, And Fluid Flow In The Yellowstone Geothermal...

    Open Energy Info (EERE)

    section of the 0.6-Ma Lava Creek ash-flow tuff. In this core, the degree of welding appears to be responsible for most of the variations in porosity, matrix...

  15. Consequences of melt transport for uranium series disequilibrium in young lavas

    E-Print Network [OSTI]

    Spiegelman, Marc W.

    Consequences of melt transport for uranium series disequilibrium in young lavas Marc Spiegelman do not actu- ally include melt transport. Here we explore the be- haviour of short

  16. Steam Trap Management

    E-Print Network [OSTI]

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

    problemA of water hammer and high back pressure. ? Exorbitantly hi~h percentage of cold trapA. ? External steam leaks within the steam trap stations, bypasA valves and/or strainer blowdown valvefl open, blowin~ steam. ! I ? Dirt nssociated... Trapping 2 Trap Installed Backwards 1 Misapplication of Technology 1 Strainer Blowdown Connections Capped 285 (*b) Test Tee Connections Capped 11 Trap Inlet Connected to Steam Line Strainer Blowdown Connection 3 Water Logged Coils (Vacuum Present) 7...

  17. Evaluating Steam Trap Performance

    E-Print Network [OSTI]

    Fuller, N. Y.

    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... that live steam loss is the heaviest contributor to the annual operating cost of any steam trap and that maintenance frequency and repair cost are also more important than a trap's first cost. INTRODUCTION Steam traps used on distribution line drip...

  18. Two-component Bose gas trapped by harmonic and annular potentials: Supercurrent, vortex flow and instability of superfluidity by Rabi coupling

    E-Print Network [OSTI]

    Ino, Hayato; Ichinose, Ikuo

    2015-01-01T23:59:59.000Z

    In this paper, we study a system of two-component Bose gas in an artificial magnetic field trapped by concentric harmonic and annular potentials, respectively. The system is realized by gases with two-internal states like the hyperfine states of $^{87}$Rb. We are interested in effects of a Rabi oscillation between them. Two-component Bose Hubbard model is introduced to describe the system, and Gross-Pitaevskii equations are used to study the system. We first study the Bose gas system in the annular trap by varying the width of the annulus and strength of the magnetic field, in particular, we focus on the phase slip and superflow. Then we consider the coupled Bose gas system in a magnetic field. In a strong magnetic field, vortices form a Abrikosov triangular lattice in both Bose-Einstein condensates (BECs), and locations of vortices in the BECs correlate with each other by the Rabi coupling. However, as the strength of the Rabi coupling is increased, vortices start to vibrate around their equilibrium location...

  19. 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 ...

  20. 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...

  1. 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.

  2. 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.

  3. 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.

  4. 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 ...

  5. 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.

  6. Steam Trap Application

    E-Print Network [OSTI]

    Murphy, J. J.

    1982-01-01T23:59:59.000Z

    Equipment Collecting leg, same size as equip ment connection but not less than Install a Yarway Process Trap below be drained. Install a Provide vacuum strainer with a blow down valve. Use and Yarway Aldrain valves full ported stop valves, (gate... and Corrosion Problems Like any critical control device the steam trap should be protected from dirt and scale if optimum operation and adequate service life are to be attained. Strainers should be equipped with blowdown valves to provide an effective...

  7. Ar/Ar ages from transitionally magnetized lavas on La Palma, Canary Islands, and the geomagnetic instability timescale

    E-Print Network [OSTI]

    Singer, Bradley S.

    Ar/Ar ages from transitionally magnetized lavas on La Palma, Canary Islands, and the geomagnetic the north and south walls of Barranco de los Tilos on the island of La Palma, Canary Islands, reveals from transitionally magnetized lavas on La Palma, Canary Islands, and the geomagnetic instability

  8. Microfabricated cylindrical ion trap

    DOE Patents [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.

  9. Short communication Origins and implications of zigzag rift patterns on lava lakes

    E-Print Network [OSTI]

    Manga, Michael

    the zigzags. Similar patterns are observed in analog wax experiments in which molten wax acts as cooling and solidifying lava. We perform a series of these wax experiments to find the relationship between , A of spreading and solidification speeds; the amplitude A is limited by the thickness of the solid wax crust

  10. JOURNAL OF PETROLOGY VOLUME 39 NUMBER 1 PAGES 125154 1998 Chemical and Isotopic Composition of Lavas

    E-Print Network [OSTI]

    Stern, Robert J.

    of the Mariana Trough extension axis. The source, reflecting the arc-like nature of the source region and isotopic compositions of igneous rocks the mantle. `True' back-arc basin basalts are generated upwelling in mature ex-basalts in the south which become increasingly similar to arc lavas tensional

  11. 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.

  12. 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.

  13. 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.

  14. APRIL 2009 FERNANDINA VOLCANO ERUPTION, GALAPAGOS ISLANDS, ECUADOR: THERMAL MAPPING OF THE LAVA FLOWS EMITTED

    E-Print Network [OSTI]

    Geist, Dennis

    , with a maximum subsidence of about 300m [Simkin and Howard,1970]. Recent activity at Fernandina includes

  15. 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.

  16. Energy Conservation Through Effective Steam Trapping

    E-Print Network [OSTI]

    Diamante, L.; Nagengast, C.

    1979-01-01T23:59:59.000Z

    fixed at one end with the valve plug on the other. The bellows are fillediwith the valve plug on the other. The bellows are filled with a liquid whose boiling temperature/pressure relationship parallels that of water only a few degrees be~ow it... resistance to the flow based on valve plug position. This promotes smooth control and additionally by allowing the pressure drop to occur in steps reduces wear on the critical seating surfaces. This trap provides excellent proportional control without...

  17. Gated charged-particle trap

    DOE Patents [OSTI]

    Benner, W. Henry (Danville, CA)

    1999-01-01T23:59:59.000Z

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

  18. Cryogenic Ion Trapping Systems with Surface-Electrode Traps

    E-Print Network [OSTI]

    P. B. Antohi; D. Schuster; G. M. Akselrod; J. Labaziewicz; Y. Ge; Z. Lin; W. S. Bakr; I. L. Chuang

    2008-07-29T23:59:59.000Z

    We present two simple cryogenic RF ion trap systems in which cryogenic temperatures and ultra high vacuum pressures can be reached in as little as 12 hours. The ion traps are operated either in a liquid helium bath cryostat or in a low vibration closed cycle cryostat. The fast turn around time and availability of buffer gas cooling made the systems ideal for testing surface-electrode ion traps. The vibration amplitude of the closed cycled cryostat was found to be below 106 nm. We evaluated the systems by loading surface-electrode ion traps with $^{88}$Sr$^+$ ions using laser ablation, which is compatible with the cryogenic environment. Using Doppler cooling we observed small ion crystals in which optically resolved ions have a trapped lifetime over 2500 minutes.

  19. Subduction Controls of Hf and Nd Isotopes in Lavas of the Aleutian Island Arc

    SciTech Connect (OSTI)

    Yogodzinski, Gene; Vervoort, Jeffery; Brown, Shaun Tyler; Gerseny, Megan

    2010-08-29T23:59:59.000Z

    The Hf and Nd isotopic compositions of 71 Quaternary lavas collected from locations along the full length of the Aleutian island arc are used to constrain the sources of Aleutian magmas and to provide insight into the geochemical behavior of Nd and Hf and related elements in the Aleutian subduction-magmatic system. Isotopic compositions of Aleutian lavas fall approximately at the center of, and form a trend parallel to, the terrestrial Hf-Nd isotopic array with {var_epsilon}{sub Hf} of +12.0 to +15.5 and {var_epsilon}{sub Nd} of +6.5 to +10.5. Basalts, andesites, and dacites within volcanic centers or in nearby volcanoes generally all have similar isotopic compositions, indicating that there is little measurable effect of crustal or other lithospheric assimilation within the volcanic plumbing systems of Aleutian volcanoes. Hafnium isotopic compositions have a clear pattern of along-arc increase that is continuous from the eastern-most locations near Cold Bay to Piip Seamount in the western-most part of the arc. This pattern is interpreted to reflect a westward decrease in the subducted sediment component present in Aleutian lavas, reflecting progressively lower rates of subduction westward as well as decreasing availability of trench sediment. Binary bulk mixing models (sediment + peridotite) demonstrate that 1-2% of the Hf in Aleutian lavas is derived from subducted sediment, indicating that Hf is mobilized out of the subducted sediment with an efficiency that is similar to that of Sr, Pb and Nd. Low published solubility for Hf and Nd in aqueous subduction fluids lead us to conclude that these elements are mobilized out of the subducted component and transferred to the mantle wedge as bulk sediment or as a silicate melt. Neodymium isotopes also generally increase from east to west, but the pattern is absent in the eastern third of the arc, where the sediment flux is high and increases from east to west, due to the presence of abundant terrigenous sediment in the trench east of the Amlia Fracture Zone, which is being subducting beneath the arc at Seguam Island. Mixing trends between mantle wedge and sediment end members become flatter in Hf-Nd isotope space at locations further west along the arc, indicating that the sediment end member in the west has either higher Nd/Hf or is more radiogenic in Hf compared to Nd. This pattern is interpreted to reflect an increase in pelagic clay relative to the terrigenous subducted sedimentary component westward along the arc. Results of this study imply that Hf does not behave as a conservative element in the Aleutian subduction system, as has been proposed for some other arcs.

  20. Cryogenic silicon surface ion trap

    E-Print Network [OSTI]

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

    2015-05-01T23:59:59.000Z

    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.

  1. Radiation trapping in coherent media

    E-Print Network [OSTI]

    A. B. Matsko; I. Novikova; M. O. Scully; G. R. Welch

    2001-01-31T23:59:59.000Z

    We show that the effective decay rate of Zeeman coherence, generated in a Rb87 vapor by linearly polarized laser light, increases significantly with the atomic density. We explain this phenomenon as the result of radiation trapping. Our study shows that radiation trapping must be taken into account to fully understand many electromagnetically induced transparency experiments with optically thick media.

  2. 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 ...

  3. 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.

  4. JOURNAL DE PHYSIQUE Colloque C6, supplkment au no 12, Tome 37, De'cembre 1976, page C6-829 MOSSBAUER STUDIES OF ICELANDIC LAVAS

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    -829 MOSSBAUER STUDIES OF ICELANDIC LAVAS 0. HELGASON, S. STEINTHORSSON Science Institute, University of Iceland ktudiks par la spectroscopie Mossbauer. On a trouvk qu'une haute vitesse de solidification cause un plus. Abstract. - Two samples of lava from Iceland have been studied by use of Mossbauer spec- troscopy

  5. Mini ion trap mass spectrometer

    DOE Patents [OSTI]

    Dietrich, Daniel D. (Livermore, CA); Keville, Robert F. (Valley Springs, CA)

    1995-01-01T23:59:59.000Z

    An ion trap which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10.sup.9 and commercial mass spectrometers requiring 10.sup.4 ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products.

  6. Mini ion trap mass spectrometer

    DOE Patents [OSTI]

    Dietrich, D.D.; Keville, R.F.

    1995-09-19T23:59:59.000Z

    An ion trap is described which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10{sup 9} and commercial mass spectrometers requiring 10{sup 4} ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products. 10 figs.

  7. 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.

  8. [The Journal of Geology, 2004, volume 112, p. 91110] No copyright is claimed for this article. It remains in the public domain. Geochemical Discrimination of Five Pleistocene Lava-Dam Outburst-

    E-Print Network [OSTI]

    Poreda, Robert J.

    . It remains in the public domain. 91 Geochemical Discrimination of Five Pleistocene Lava-Dam Outburst- Flood@usgs.gov) A B S T R A C T Pleistocene basaltic lava dams and outburst-flood deposits in the western Grand Canyon outburst-flood deposit came from a common source, a lava dam. With these data, it is possible

  9. 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.

  10. Debris Flows the Rapids of

    E-Print Network [OSTI]

    Shale of the Tonto Group (fig. 2a). Other prominent sources include the Dox Sandstone, Cardenas Lava

  11. Microfabricated linear Paul-Straubel ion trap

    DOE Patents [OSTI]

    Mangan, Michael A. (Albuquerque, NM); Blain, Matthew G. (Albuquerque, NM); Tigges, Chris P. (Albuquerque, NM); Linker, Kevin L. (Albuquerque, NM)

    2011-04-19T23:59:59.000Z

    An array of microfabricated linear Paul-Straubel ion traps can be used for mass spectrometric applications. Each ion trap comprises two parallel inner RF electrodes and two parallel outer DC control electrodes symmetric about a central trap axis and suspended over an opening in a substrate. Neighboring ion traps in the array can share a common outer DC control electrode. The ions confined transversely by an RF quadrupole electric field potential well on the ion trap axis. The array can trap a wide array of ions.

  12. Surface-electrode point Paul trap

    SciTech Connect (OSTI)

    Kim, Tony Hyun; Herskind, Peter F.; Chuang, Isaac L. [Center for Ultracold Atoms, Department of Physics, Massachusetts Institute of Technology 77 Massachusetts Avenue, Cambridge, Massachusetts 02139 (United States); Kim, Taehyun; Kim, Jungsang [Department of Electrical and Computer Engineering, Duke University Durham, North Carolina 27708 (United States)

    2010-10-15T23:59:59.000Z

    We present a model as well as experimental results for a surface electrode radiofrequency Paul trap that has a circular electrode geometry well suited for trapping single ions and two-dimensional planar ion crystals. The trap design is compatible with microfabrication and offers a simple method by which the height of the trapped ions above the surface may be changed in situ. We demonstrate trapping of single {sup 88}Sr{sup +} ions over an ion height range of 200-1000 {mu}m for several hours under Doppler laser cooling and use these to characterize the trap, finding good agreement with our model.

  13. A study of the regeneration process in diesel particulate traps using a copper fuel additive

    SciTech Connect (OSTI)

    Tan, J.C.; Opris, C.N.; Baumgard, K.J.; Johnson, J.H. [Michigan Technological Univ., Houghton, MI (United States)

    1996-09-01T23:59:59.000Z

    The goals of this research are to understand the regeneration process in ceramic (Cordierite) monolith traps using a copper fuel additive and to investigate the various conditions that lead to trap regeneration failure. The copper additive lowers the trap regeneration temperature from approximately 500 C to 375 C and decreases the time necessary for regeneration. Because of these characteristics, it is important to understand the effect of the additive on regeneration when excessive particulate matter accumulation occurs in the trap. The effects of particulate mass loading on regeneration temperatures and regeneration time were studied for both the controlled (engine operated at full load rated speed) and uncontrolled conditions. The trap peak temperatures were higher for the uncontrolled than the controlled regeneration. The higher peak trap temperatures were predominantly controlled by the effect of the exhaust flow rates on the energy transfer processes. The total regeneration time was faster for the controlled regeneration compared to the uncontrolled regeneration. All traps passed the controlled regeneration tests having maximum temperatures less than 900 C. During the uncontrolled regeneration tests, trap failure occurred at 135 and 139 g particulate matter loadings. The maximum temperatures were in excess of 1,150 C. The pressure drop across the trap was modeled using the one dimensional Darcy`s law which accounted for the pressure drop due to the ceramic wall and the particulate layer. The experimental results for the substrate correlate well with the empirical substrate pressure drop models available in the literature. The models also enable an estimate to be made regarding trap mass loading. These data along with the laboratory data have indicated that mass loadings greater than 110 g followed by high temperature operation and subsequent engine idling can result in trap failures during regeneration.

  14. Thickness distribution of a cooling pyroclastic flow deposit on Augustine Volcano, Alaska: Optimization using InSAR,

    E-Print Network [OSTI]

    Thickness distribution of a cooling pyroclastic flow deposit on Augustine Volcano, Alaska of Volcanology and Geothermal Research 150 (2006) 186­201 www.elsevier.com/locate/jvolgeores #12;imagery have al., 2001), poroelastic rebound (Peltzer et al., 1996), cooling lava (Stevens et al., 2001

  15. Combined U-Th/He and 40Ar/39Ar geochronology of post-shield lavas from the Mauna Kea and Kohala volcanoes, Hawaii

    E-Print Network [OSTI]

    Aciego, S.M.

    2010-01-01T23:59:59.000Z

    to Mineralogy and Petrology 84(4), 390-405. Frey F. A. ,to Mineralogy and Petrology 100, 383-397. Williams A.J. ,series lavas. Journal of Petrology 38(7), 911-939. Dunai T.

  16. Fiber optic integration in planar ion traps

    E-Print Network [OSTI]

    George, Elizabeth Marie

    2008-01-01T23:59:59.000Z

    Atomic ion traps are are excellent tools in atomic physics for studying single ions. Accurate measurement of the ion's electronic state in these ion traps is required by both atomic clocks and quantum computation. Quantum ...

  17. instructions HisTrap FF crude,

    E-Print Network [OSTI]

    Lebendiker, Mario

    p1 instructions HisTrap FF crude, 1 ml and 5 ml i 11-0012-38 Edition AA HisTrapTM FF crude, such as degradation and oxidation of sensitive target proteins, and is therefore of great importance. HisTrap FF crude properties HisTrap FF crude 1-ml and 5-ml columns are prepacked with the affinity medium Ni Sepharose 6 Fast

  18. Syn-eruptive degassing of a single submarine lava flow : constraints on MORB CO? variability, vesiculation, and eruption dynamics

    E-Print Network [OSTI]

    Nakata, Dorene Samantha

    2010-01-01T23:59:59.000Z

    Mid-ocean ridge basalts (MORBs) exhibit a wide range of CO2 concentrations, reflecting saturation to supersaturation (and rarely undersaturation) relative to their emplacement depths. In this study, we explore the mechanisms ...

  19. 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.

  20. 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.

  1. Cooling Techniques for Trapped Ions

    E-Print Network [OSTI]

    Daniel M. Segal; Christof Wunderlich

    2014-09-24T23:59:59.000Z

    This book chapter gives an introduction to, and an overview of, methods for cooling trapped ions. The main addressees are researchers entering the field. It is not intended as a comprehensive survey and historical account of the extensive literature on this topic. We present the physical ideas behind several cooling schemes, outline their mathematical description, and point to relevant literature useful for a more in-depth study of this topic.

  2. Uranium potential of southwestern New Mexico (southern Hidalgo County), including observations on crystallization history of lavas and ash tuffs and the release of uranium from them. Final report

    SciTech Connect (OSTI)

    Walton, A.W.; Salter, T.L.; Zetterlund, D.

    1980-08-01T23:59:59.000Z

    Geological environments present in southwestern New Mexico include thick sequences of sedimentary rock including limestone, conglomerates, sandstone, and shale: igneous intrusions with associated metal deposits; caldera centers, margins, and outflow facies; and basins with marginal faults and thick late Cenozoic sedimentary fillings. Predominant rock types are Paleozoic carbonates, Mesozoic terrigeneous rocks and carbonates, and Cenozoic volcanic rocks and basin-filling terrigeneous rocks. Consideration of information available in Preliminary Reconnaissance Reports and in Hydrogeochemical and Stream Reconnaissance Reports together with 347 new whole rock chemical analyses points to three areas of anomalous uranium abundance in Hidalgo County, New Mexico. The area has experienced three major periods of igneous activity in Phanerozoic time: one associated with the Laramide cycle of the Late Cretaceous and early Tertiary, mid-Tertiary cycle of silicic volcanism with abundant calderas, and a late Tertiary cycle of mafic volcanism. Silicic volcanic rocks are the most common exposed rock type in the area, and the most enriched in uranium (range, 0.4 to 19 ppM). The most likely source for any uranium ore-forming solutions lies with this cycle of volcanism. Solutions might have been introduced during volcanism or formed later by groundwater leaching of cooled volcanic rocks. Results indicate that groundwater leaching of cooled volcanic rocks was not an effective means of mobilizing uranium in the area. Study of several rhyolite lava flows indicates that they were emplaced in supercooled condition and may have crystallized completely at temperatures well below their liquids, or they may have warmed as crystallization released latent heat. Statistical comparison of the uranium concentration revealed no differences between vitrophyres and associated felsites.

  3. The Footprint of the CO[subscript 2] Plume during Carbon Dioxide Storage in Saline Aquifers: Storage Efficiency for Capillary Trapping at the Basin Scale

    E-Print Network [OSTI]

    Juanes, Ruben

    We study a sharp-interface mathematical model of CO[subscript 2] migration in deep saline aquifers, which accounts for gravity override, capillary trapping, natural groundwater flow, and the shape of the plume during the ...

  4. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField Campaign:INEAWater UseC Supports - Energy3 PierreElectron Trapping by

  5. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField Campaign:INEAWater UseC Supports - Energy3 PierreElectron Trapping

  6. State-insensitive bichromatic optical trapping

    E-Print Network [OSTI]

    Bindiya Arora; M. S. Safronova; Charles W. Clark

    2010-05-07T23:59:59.000Z

    We propose a scheme for state-insensitive trapping of neutral atoms by using light with two independent wavelengths. In particular, we describe the use of trapping and control lasers to minimize the variance of the potential experienced by a trapped Rb atom in ground and excited states. We present calculated values of wavelength pairs for which the 5s and 5p_{3/2} levels have the same ac Stark shifts in the presence of two laser fields.

  7. Cavity sideband cooling of trapped molecules

    SciTech Connect (OSTI)

    Kowalewski, Markus; Vivie-Riedle, Regina de [Department of Chemistry, Ludwig-Maximilian-Universitaet, D-81377 Munich (Germany); Morigi, Giovanna [Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); Theoretische Physik, Universitaet des Saarlandes, D-66041 Saarbruecken (Germany); Pinkse, Pepijn W. H. [MESA Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500AE Enschede (Netherlands)

    2011-09-15T23:59:59.000Z

    The efficiency of cavity sideband cooling of trapped molecules is theoretically investigated for the case in which the infrared transition between two rovibrational states is used as a cycling transition. The molecules are assumed to be trapped either by a radiofrequency or optical trapping potential, depending on whether they are charged or neutral, and confined inside a high-finesse optical resonator that enhances radiative emission into the cavity mode. Using realistic experimental parameters and COS as a representative molecular example, we show that in this setup, cooling to the trap ground state is feasible.

  8. 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.

  9. 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.

  10. Can We Accurately Model Fluid Flow in Shale?

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

    2013 00:00 Over 20 trillion cubic meters of natural gas are trapped in shale, but many shale oil and gas producers still use models of underground fluid flow that date back to...

  11. 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 Jurgen Eschner Institut fu r Experimentalphysik, Universita

  12. Holographic optical trapping David G. Grier

    E-Print Network [OSTI]

    Grier, David

    Holographic optical trapping David G. Grier Yael Roichman Department of Physics and Center for Soft Matter Research, New York University, 4 Washington Place, New York, NY 10003 Holographic optical tweezersbeam optical traps use ful for capturing, moving and transforming mesoscopic objects. Through a combination

  13. Holographic optical trapping David G. Grier

    E-Print Network [OSTI]

    Grier, David

    Holographic optical trapping David G. Grier Yael Roichman Department of Physics and Center for Soft Matter Research, New York University, 4 Washington Place, New York, NY 10003 Holographic optical tweezers-beam optical traps use- ful for capturing, moving and transforming mesoscopic objects. Through a combination

  14. Compression of Antiproton Clouds for Antihydrogen Trapping

    E-Print Network [OSTI]

    G. B. Andresen; W. Bertsche; P. D. Bowe; C. C. Bray; E. Butler; C. L. Cesar; S. Chapman; M. Charlton; J. Fajans; M. C. Fujiwara; R. Funakoshi; D. R. Gill; J. S. Hangst; W. N. Hardy; R. S. Hayano; M. E. Hayden; R. Hydomako; M. J. Jenkins; L. V. Jorgensen; L. Kurchaninov; R. Lambo; N. Madsen; P. Nolan; K. Olchanski; A. Olin; A. Povilus; P. Pusa; F. Robicheaux; E. Sarid; S. Seif El Nasr; D. M. Silveira; J. W. Storey; R. I. Thompson; D. P. van der Werf; J. S. Wurtele; Y. Yamazaki

    2008-06-30T23:59:59.000Z

    Control of the radial profile of trapped antiproton clouds is critical to trapping antihydrogen. We report the first detailed measurements of the radial manipulation of antiproton clouds, including areal density compressions by factors as large as ten, by manipulating spatially overlapped electron plasmas. We show detailed measurements of the near-axis antiproton radial profile and its relation to that of the electron plasma.

  15. 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.

  16. Ion Trap in a Semiconductor Chip

    E-Print Network [OSTI]

    D. Stick; W. K. Hensinger; S. Olmschenk; M. J. Madsen; K. Schwab; C. Monroe

    2006-01-09T23:59:59.000Z

    The electromagnetic manipulation of isolated atoms has led to many advances in physics, from laser cooling and Bose-Einstein condensation of cold gases to the precise quantum control of individual atomic ion. Work on miniaturizing electromagnetic traps to the micrometer scale promises even higher levels of control and reliability. Compared with 'chip traps' for confining neutral atoms, ion traps with similar dimensions and power dissipation offer much higher confinement forces and allow unparalleled control at the single-atom level. Moreover, ion microtraps are of great interest in the development of miniature mass spectrometer arrays, compact atomic clocks, and most notably, large scale quantum information processors. Here we report the operation of a micrometer-scale ion trap, fabricated on a monolithic chip using semiconductor micro-electromechanical systems (MEMS) technology. We confine, laser cool, and measure heating of a single 111Cd+ ion in an integrated radiofrequency trap etched from a doped gallium arsenide (GaAs) heterostructure.

  17. Control considerations for an on-line, active regeneration system for diesel particulate traps

    SciTech Connect (OSTI)

    Stiglic, P.; Hardy, J.; Gabelman, B. (Garrett Automotive Group, Allied-Singal, Torrance, CA (US))

    1989-07-01T23:59:59.000Z

    The authors are developing an exhaust aftertreatment system aimed at particulate emissions reduction from commercial diesel engines. The system uses a ceramic wall flow filter to trap the particulates, and regeneration is effected by raising gas temperature by throttling the exhaust downstream of the turbocharger. Lab testing at steady conditions demonstrated good performance with both catalyzed and uncatalyzed traps. Road testing shows the regeneration must be accomplished under severe transient conditions created by the normal vehicle operating modes. Primary efforts are to accommodate those transients using advanced control and digital computational techniques. Some of those techniques are described and are shown to yield improved control performance.

  18. When a trap is not a trap: converging entry and exit rates and their effect on trap saturation of black sea bass (Centropristis striata)

    E-Print Network [OSTI]

    When a trap is not a trap: converging entry and exit rates and their effect on trap saturation entries and exits of black sea bass (Centropristis striata) from chevron traps (n 26) to quantify catch at50 min, when the entry ratedeclined and the exit rate increased to a point where their confidence

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

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

    (Lean NOx Trap) Fundamentals (Agreement 10049 - PNNL Project 47120) NOx Adsorber (Lean NOx Trap) Fundamentals (Agreement 10049 - PNNL Project 47120) Presentation from the U.S....

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

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

    Sam Crane August 28, 2003 H 2 -Assisted NOx Traps: Test Cell Results Vehicle Installations 2 Project Objectives * Determine Advantages of H 2 Assisted NO x Trap Regeneration *...

  1. 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...

  2. Vibrational Cooling in A Cold Ion Trap: Vibrationally Resolved...

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

    Vibrational Cooling in A Cold Ion Trap: Vibrationally Resolved Photoelectron Spectroscopy of Cold C60- Anions. Vibrational Cooling in A Cold Ion Trap: Vibrationally Resolved...

  3. 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...

  4. 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...

  5. Correlation of Cycles in Lava Lake Motion and Degassing at Erebus Volcano, Antarctica

    E-Print Network [OSTI]

    Peters, Nial; Oppenheimer, Clive; Killingsworth, Drea Rae; Frechette, Jed; Kyle, Philip

    2014-08-19T23:59:59.000Z

    the figure for clarity.314 5. Discussion Given the apparent complexity of Erebuss shallow magmatic system [e.g. Zandomeneghi315 et al., 2013] and the sensitivity of multi-phase flows to small changes in system parameters316 [e.g. Molina et al., 2012... :24 on 17 December 2012) have been omitted from the figure for clarity. 5. Discussion Given the apparent complexity of Erebuss shallow magmatic system [e.g., Zandomeneghi et al., 2013] and the sensitivity of multiphase flows to small changes in system...

  6. Parameter exploration of optically trapped liquid aerosols

    E-Print Network [OSTI]

    D. R. Burnham; P. J. Reece; D. McGloin

    2010-06-24T23:59:59.000Z

    When studying the motion of optically trapped particles on the $\\mu s$ time scale, in low viscous media such as air, inertia cannot be neglected. Resolution of unusual and interesting behaviour not seen in colloidal trapping experiments is possible. In attempt to explain the phenomena we use power spectral methods to perform a parameter study of the Brownian motion of optically trapped liquid aerosol droplets concentrated around the critically damped regime. We present evidence that the system is suitably described by a simple harmonic oscillator model which must include a description of Fax\\'{e}n's correction, but not necessarily frequency dependent hydrodynamic corrections to Stokes' law. We also provide results describing how the system behaves under several variables and discuss the difficulty in decoupling the parameters responsible for the observed behaviour. We show that due to the relatively low dynamic viscosity and high trap stiffness it is easy to transfer between over- and under-damped motion by experimentally altering either trap stiffness or damping. Our results suggest stable aerosol trapping may be achieved in under-damped conditions, but the onset of deleterious optical forces at high trapping powers prevents the probing of the upper stability limits due to Brownian motion.

  7. 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.

  8. Trapping efficiency depending on particulate size

    SciTech Connect (OSTI)

    Mayer, A.; Czerwinski, J.; Scheidegger, P.

    1996-09-01T23:59:59.000Z

    There is growing concern about the risk potential of Diesel particulates. This prompted two Swiss R and D projects focused on the capabilities of different soot trap concepts for filtering finest particulates. Eight different filter media, some in numerous variants, were tested on four different Diesel engines. All traps attained their gravimetric target. However, there are noticeable performance differences for finest particulates at or smaller than 50 nm. Fiber deep filters seem to be noticeably better than other filter types. If the carcinogens are mainly the finest particulates, then this criterion may become important in future trap evaluation.

  9. 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.

  10. Nonlinear Spectroscopy of Trapped Ions

    E-Print Network [OSTI]

    Frank Schlawin; Manuel Gessner; Shaul Mukamel; Andreas Buchleitner

    2014-10-07T23:59:59.000Z

    Nonlinear spectroscopy employs a series of laser pulses to interrogate dynamics in large interacting many-body systems, and has become a highly successful method for experiments in chemical physics. Current quantum optical experiments approach system sizes and levels of complexity which require the development of efficient techniques to assess spectral and dynamical features with scalable experimental overhead. However, established methods from optical spectroscopy of macroscopic ensembles cannot be applied straightforwardly to few-atom systems. Based on the ideas proposed in [M. Gessner et al. New J. Phys. 16 092001 (2014)], we develop a diagrammatic approach to construct nonlinear measurement protocols for controlled quantum systems and discuss experimental implementations with trapped ion technology in detail. These methods in combination with distinct features of ultra-cold matter systems allow us to monitor and analyze excitation dynamics in both the electronic and vibrational degrees of freedom. They are independent of system size, and can therefore reliably probe systems where, e.g., quantum state tomography becomes prohibitively expensive. We propose signals that can probe steady state currents, detect the influence of anharmonicities on phonon transport, and identify signatures of chaotic dynamics near a quantum phase transition in an Ising-type spin chain.

  11. 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. ...

  12. Molten Hydroxide Trapping Process for Radioiodine

    SciTech Connect (OSTI)

    Trowbridge, L.D.

    2003-01-28T23:59:59.000Z

    A molten hydroxide trapping process has been considered for removing radioiodine species from off-gas streams whereby iodine is reacted directly with molten hydroxides such as NaOH or KOH. The resulting product is the corresponding iodide, which can be separated by simple cooling of the molten mixture to grow the iodide primary phase once the mixture reaches 70-80 mol% in the iodide component. Thermodynamic analysis indicates that such a chemical process is highly favorable. Experimental testing of the trapping process using molecular iodine showed trapping of up to 96% of the volatile iodine. The trapping efficiency was dependent on operational parameters such as temperature and gas-melt contact efficiency, and higher efficiencies are expected as the process is further developed. While an iodide phase could be effectively isolated by slow cooling of a molten iodide-hydroxide mixture, the persistent appearance of hydroxide indicated that an appreciable solubility of hydroxide occurred in the iodide phase.

  13. 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...

  14. Capturing Energy Savings with Steam Traps

    E-Print Network [OSTI]

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

    , it's important to select and install the correct type and size steam trap for each application. This means a corruninnent must be made to training those who select, install, test and maintain steam traps on a. daily Scott A. French Application... generated. This paper will review each of these topics and then explore some of the new services, products, practices and technology available to help you maintain or improve the efficiency of your steam system. COSTLY STEAM LEAKS ENERGY RESOURCES...

  15. 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, 55235527 (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.

  16. RICE UNIVERSITY A New Optical Trap System for

    E-Print Network [OSTI]

    Killian, Thomas C.

    profiles . . . . . . . . . . . . . . . . . . . . 14 2.1.3 Alignment of the loading trap beams . . . . . . . . . . . . . . 14 2.1.4 Power locking system for loading trap . . . . . . . . . . . . . . 15 2.2 Loading trap depth . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 3.1.1 Description of trap optical design and beam profiles . . . . . . 22 3.1.2 Power locking

  17. 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

  18. Hydrodynamic and statistical parameters of slug flow Lev Shemer *

    E-Print Network [OSTI]

    Shemer, Lev

    distribution within the pipeline is of utmost importance and requires proper knowledge of the relevant and dispersed gas bubbles in pipelines of various inclina- tions. In vertical slug flow most of the gas-phase slug flow pattern, the bulk of the gas is trapped inside large bubbles that are separated by liquid

  19. Chapter 44. Cooling and Trapping Neutral Atoms Cooling and Trapping Neutral Atoms

    E-Print Network [OSTI]

    transition. This year, we made progress in developing novel detection and cooling techniques. 1. SpinChapter 44. Cooling and Trapping Neutral Atoms 44-1 Cooling and Trapping Neutral Atoms RLE Groups in optical lattices. Additional cooling methods will be needed to reach this very interesting temperature

  20. 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.

  1. 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.; Moosmller, 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.

  2. Hydrodynamic effect on oil accumulation in a stratigraphic trap, Kitty Field, Powder River Basin, Wyoming

    E-Print Network [OSTI]

    Larberg, Gregory Martin

    1976-01-01T23:59:59.000Z

    stratigraphic traps in the Lower Cretaceous Muddy Sandstones on the east flank of the basin (Figure 1). The nine ? township area immediately surrounding Kitty in- cludes Kingsbury and Mill ? Gillette fields and is well ? suited for hydrodynamic study because... understanding of the relationships between pressures, flow, and the rocks themselves. 14 Nethods Subsurface data from the nine township area surround- ing Kitty field is abundant and readily available from in- dustry sources. Over 530 class "A" (analyzable...

  3. 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

    2015-05-05T23:59:59.000Z

    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.

  4. 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.

  5. Controlling fast transport of cold trapped ions

    E-Print Network [OSTI]

    Andreas Walther; Frank Ziesel; Thomas Ruster; Sam T. Dawkins; Konstantin Ott; Max Hettrich; Kilian Singer; Ferdinand Schmidt-Kaler; Ulrich Poschinger

    2012-06-02T23:59:59.000Z

    We realize fast transport of ions in a segmented micro-structured Paul trap. The ion is shuttled over a distance of more than 10^4 times its groundstate wavefunction size during only 5 motional cycles of the trap (280 micro meter in 3.6 micro seconds). Starting from a ground-state-cooled ion, we find an optimized transport such that the energy increase is as low as 0.10 $\\pm$ 0.01 motional quanta. In addition, we demonstrate that quantum information stored in a spin-motion entangled state is preserved throughout the transport. Shuttling operations are concatenated, as a proof-of-principle for the shuttling-based architecture to scalable ion trap quantum computing.

  6. Screening the Hanford tanks for trapped gas

    SciTech Connect (OSTI)

    Whitney, P.

    1995-10-01T23:59:59.000Z

    The Hanford Site is home to 177 large, underground nuclear waste storage tanks. Hydrogen gas is generated within the waste in these tanks. This document presents the results of a screening of Hanford`s nuclear waste storage tanks for the presence of gas trapped in the waste. The method used for the screening is to look for an inverse correlation between waste level measurements and ambient atmospheric pressure. If the waste level in a tank decreases with an increase in ambient atmospheric pressure, then the compressibility may be attributed to gas trapped within the waste. In this report, this methodology is not used to estimate the volume of gas trapped in the waste. The waste level measurements used in this study were made primarily to monitor the tanks for leaks and intrusions. Four measurement devices are widely used in these tanks. Three of these measure the level of the waste surface. The remaining device measures from within a well embedded in the waste, thereby monitoring the liquid level even if the liquid level is below a dry waste crust. In the past, a steady rise in waste level has been taken as an indicator of trapped gas. This indicator is not part of the screening calculation described in this report; however, a possible explanation for the rise is given by the mathematical relation between atmospheric pressure and waste level used to support the screening calculation. The screening was applied to data from each measurement device in each tank. If any of these data for a single tank indicated trapped gas, that tank was flagged by this screening process. A total of 58 of the 177 Hanford tanks were flagged as containing trapped gas, including 21 of the 25 tanks currently on the flammable gas watch list.

  7. Parametric Resonance of Optically Trapped Aerosols

    E-Print Network [OSTI]

    R. Di Leonardo; G. Ruocco; J. Leach; M. J. Padgett; A. J. Wright; J. M. Girkin; D. R. Burnham; D. McGloin

    2007-02-23T23:59:59.000Z

    The Brownian dynamics of an optically trapped water droplet are investigated across the transition from over to under-damped oscillations. The spectrum of position fluctuations evolves from a Lorentzian shape typical of over-damped systems (beads in liquid solvents), to a damped harmonic oscillator spectrum showing a resonance peak. In this later under-damped regime, we excite parametric resonance by periodically modulating the trapping power at twice the resonant frequency. The power spectra of position fluctuations are in excellent agreement with the obtained analytical solutions of a parametrically modulated Langevin equation.

  8. Reduce Steam Trap Failures at Chambers Works

    E-Print Network [OSTI]

    Kouba, C.

    Maintenance Mechanic), Rick Ragsdale (Fluor), Joyce Finkle (PC), Denis P Humphreys (Fluoroproducts), Jack Hemmert, Charlie Brown 10/20/2010 2 Steam trap failures are nothing new Steam trap programs are nothing new WHAT makes this program have such a huge... impact and How is it sustainable HOW we went about finding a solution What do you have learn from this 10/20/2010 3 Six Sigma Methodology was KEY to success Savings: $1MM annualized in only 6 months! 10/20/2010 4Define: Project CTQ?s Customer...

  9. 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.

  10. Thermal electric vapor trap arrangement and method

    DOE Patents [OSTI]

    Alger, Terry (Tracy, CA)

    1988-01-01T23:59:59.000Z

    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.

  11. 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.

  12. Impact of structured heterogeneities on reactive two-phase porous flow

    E-Print Network [OSTI]

    Reeves, Daniel

    Two-phase flow through heterogeneous media leads to scale-free distributions of irregularly shaped pockets of one fluid trapped within the other. Although reactions within these fluids are often modeled at the homogeneous ...

  13. INFLUENCE OF LOCAL CAPILLARY TRAPPING ON CONTAINMENT SYSTEM EFFECTIVENESS

    SciTech Connect (OSTI)

    Bryant, Steven

    2014-03-31T23:59:59.000Z

    Immobilization of CO2 injected into deep subsurface storage reservoirs is a critical component of risk assessment for geologic CO2 storage (GCS). Local capillary trapping (LCT) is a recently established mode of immobilization that arises when CO2 migrates due to buoyancy through heterogeneous storage reservoirs. This project sought to assess the amount and extent of LCT expected in storage formations under a range of injection conditions, and to confirm the persistence of LCT if the seal overlying the reservoir were to lose its integrity. Numerical simulation using commercial reservoir simulation software was conducted to assess the influence of injection. Laboratory experiments, modeling and numerical simulation were conducted to assess the effect of compromised seal integrity. Bench-scale (0.6 m by 0.6 m by 0.03 m) experiments with surrogate fluids provided the first empirical confirmation of the key concepts underlying LCT: accumulation of buoyant nonwetting phase at above residual saturations beneath capillary barriers in a variety of structures, which remains immobile under normal capillary pressure gradients. Immobilization of above-residual saturations is a critical distinction between LCT and the more familiar residual saturation trapping. To estimate the possible extent of LCT in a storage reservoir an algorithm was developed to identify all potential local traps, given the spatial distribution of capillary entry pressure in the reservoir. The algorithm assumes that the driving force for CO2 migration can be represented as a single value of critical capillary entry pressure Pc,entrycrit, such that cells with capillary entry pressure greater/less than Pc,entrycrit act as barriers/potential traps during CO2 migration. At intermediate values of Pc,entrycrit, the barrier regions become more laterally extensive in the reservoir, approaching a percolation threshold while non-barrier regions remain numerous. The maximum possible extent of LCT thus occurs at Pc,entrycrit near this threshold. Testing predictions of this simple algorithm against full-physics simulations of buoyancy-driven CO2 migration support the concept of critical capillary entry pressure. However, further research is needed to determine whether a single value of critical capillary entry pressure always applies and how that value can be determined a priori. Simulations of injection into high-resolution (cells 0.3 m on a side) 2D and 3D heterogeneous domains show two characteristic behaviors. At small gravity numbers (vertical flow velocity much less than horizontal flow velocity) the CO2 fills local traps as well as regions that would act as local barriers if CO2 weremoving only due to buoyancy. When injection ceases, the CO2 migrates vertically to establish large saturations within local traps and residual saturation elsewhere. At large gravity numbers, the CO2 invades a smaller portion of the perforated interval. Within this smaller swept zone the local barriers are not invaded, but local traps are filled to large saturation during injection and remain during post-injection gravity-driven migration. The small gravity number behavior is expected in the region within 100 m of a vertical injection well at anticipated rates of injection for commercial GCS. Simulations of leakage scenarios (through-going region of large permeability imposed in overlying seal) indicate that LCT persists (i.e. CO2 remains held in a large fraction of the local iv traps) and the persistence is independent of injection rate during storage. Simulations of leakage for the limiting case of CO2 migrating vertically from an areally extensive emplacement in the lower portion of a reservoir showed similar strong persistence of LCT. This research has two broad implications for GCS. The first is that LCT can retain a significant fraction of the CO2 stored in a reservoir above and beyond the residual saturation -- if the overlying seal were to fail. Thus frameworks for risk assessment should be extended to account for LCT. The second implication is that compared to press

  14. 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 ...

  15. Ideal Multipole Ion Traps from Planar Ring Electrodes

    E-Print Network [OSTI]

    Robert J. Clark

    2012-08-21T23:59:59.000Z

    We present designs for multipole ion traps based on a set of planar, annular, concentric electrodes which require only rf potentials to confine ions. We illustrate the desirable properties of the traps by considering a few simple cases of confined ions. We predict that mm-scale surface traps may have trap depths as high as tens of electron volts, or micromotion amplitudes in a 2-D ion crystal as low as tens of nanometers, when parameters of a magnitude common in the field are chosen. Several example traps are studied, and the scaling of those properties with voltage, frequency, and trap scale, for small numbers of ions, is derived. In addition, ions with very high charge-to-mass ratios may be confined in the trap, and species of very different charge-to-mass ratios may be simultaneously confined. Applications of these traps include quantum information science, frequency metrology, and cold ion-atom collisions.

  16. 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.

  17. 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 ...

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

    E-Print Network [OSTI]

    Boynton, T.; Dewhirst, B.

    1980-01-01T23:59:59.000Z

    This paper will deal with steam trap surveys and preventive maintenance programs and the energy savings that may be realized from such efforts. Trap survey organization, flexibility, simplicity, and mechanics will be reviewed, including the economic...

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

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

    Single microbe trap and release in sub-microfluidics. Single microbe trap and release in sub-microfluidics. Abstract: Lab-on-a-chip systems have substantially impacted the way...

  20. 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.

  1. Simulating a quantum magnet with trapped ions

    E-Print Network [OSTI]

    Loss, Daniel

    systems we need a quantum leap in computer simulations. We cannot translate quantum behaviour arising from dynamics, we need a `quantum leap' in simulation efficiency. As proposed in ref. 1, a universal quantumLETTERS Simulating a quantum magnet with trapped ions A. FRIEDENAUER*, H. SCHMITZ*, J. T. GLUECKERT

  2. 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.

  3. Dynamical Localization in the Paul Trap

    E-Print Network [OSTI]

    M. El Ghafar; P. Torma; V. Savichev; E. Mayr; A. Zeiler; W. P. Schleich

    1996-12-18T23:59:59.000Z

    We show that quantum localization occurs in the center-of-mass motion of an ion stored in a Paul trap and interacting with a standing laser field. The present experimental state of the art makes the observation of this phenomenon feasible.

  4. Trapping Light With Mirrors David Milovich Jr.

    E-Print Network [OSTI]

    Milovich, David

    Trapping Light With Mirrors David Milovich Jr. February 20, 2004 Abstract. We show that, given finitely many line-segment mirrors in the plane, that do not touch, and an arbitrary point source of light emitted light beams escape. This result is shown to imply that, for a given point source of light

  5. Acceleration of trapped particles and beams

    E-Print Network [OSTI]

    Er'el Granot; Boris Malomed

    2011-07-30T23:59:59.000Z

    The dynamics of a quantum particle bound by an accelerating delta-functional potential is investigated. Three cases are considered, using the reference frame moving along with the {\\delta}-function, in which the acceleration is converted into the additional linear potential. (i) A stationary regime, which corresponds to a resonance state, with a minimum degree of delocalization, supported by the accelerating potential trap. (ii) A pulling scenario: an initially bound particle follows the accelerating delta-functional trap, within a finite time. (iii) The pushing scenario: the particle, which was initially localized to the right of the repulsive delta-function, is shoved to the right by the accelerating potential. For the two latter scenarios, the life time of the trapped particle, and the largest velocity to which it can be accelerated while staying trapped, are found. Analytical approximations are developed for the cases of small and large accelerations in the pulling regime, and also for a small acceleration in the stationary situation, and in the regime of pushing. The same regimes may be realized by Airy-like planar optical beams guided by a narrow bending potential channel or crest. Physical estimates are given for an atom steered by a stylus of a scanning tunneling microscope (STM), and for the optical beam guided by a bending stripe.

  6. Pore-scale study of capillary trapping mechanism during CO2 injection in geological formations

    SciTech Connect (OSTI)

    Bandara, Uditha C.; Tartakovsky, Alexandre M.; Palmer, Bruce J.

    2011-11-01T23:59:59.000Z

    Geological sequestration of CO{sub 2} gas emerged as a promising solution for reducing amount of green house gases in atmosphere. A number of continuum scale models are available to describe the transport phenomena of CO{sub 2} sequestration. These models rely heavily on a phenomenological description of subsurface transport phenomena and the predictions can be highly uncertain. Pore-scale models provide a better understanding of fluid displacement processes, nonetheless such models are rare. In this work we use a Smoothed Particle Hydrodynamics (SPH) model to study pore-scale displacement and capillary trapping mechanisms of super-critical CO{sub 2} in the subsurface. Simulations are carried out to investigate the effects of gravitational, viscous, and capillary forces in terms of Gravity, Capillary, and Bond numbers. Contrary to the other published continuum scale investigations, we found that not only Gravity number but also Capillary number plays an important role on the fate of injected CO{sub 2}. For large Gravity numbers (on the order of 10), most of the injected CO{sub 2} reaches the cap-rock due to gravity segregation. A significant portion of CO{sub 2} gets trapped by capillary forces when Gravity number is small (on the order of 0.1). When Gravity number is moderately high (on the order of 1), trapping patterns are heavily dependent on Capillary number. If Capillary number is very small (less than 0.001), then capillary forces dominate the buoyancy forces and a significant fraction of injected CO{sub 2} is trapped by the capillary forces. Conversely, if Capillary number is high (higher than 0.001), capillary trapping is relatively small since buoyancy dominates the capillary forces. In addition, our simulations reveal different types of capillary trapping and flow displacement mechanisms during and after injection. In gravity dominated cases leave behind was the widespread trapping mechanism. Division was the primary trapping mechanism in viscous dominated cases. In capillary dominated cases, snap-off of the CO{sub 2} plume is the most commonly observed displacement mechanism. Large CO{sub 2} blobs are created due to coalescence mechanism.

  7. A system for trapping barium ions in a microfabricated surface trap

    SciTech Connect (OSTI)

    Graham, R. D., E-mail: rdgraham@uw.edu; Sakrejda, T.; Wright, J.; Zhou, Z.; Blinov, B. B., E-mail: blinov@uw.edu [University of Washington, Department of Physics, Box 351560, Seattle, WA 98195-1560 (United States); Chen, S.-P. [University of Washington, Department of Electrical Engineering, 185 Stevens Way, Paul Allen Center - Room AE100R, Campus Box 352500, Seattle, WA 98195-2500 (United States)

    2014-05-15T23:59:59.000Z

    We have developed a vacuum chamber and control system for rapid testing of microfabricated surface ion traps. Our system is modular in design and is based on an in-vacuum printed circuit board with integrated filters. We have used this system to successfully trap and cool barium ions and have achieved ion dark' lifetimes of 31.6s 3.4s with controlled shuttling of ions. We provide a detailed description of the ion trap system including the in-vacuum materials used, control electronics and neutral atom source. We discuss the challenges presented in achieving a system which can work reliably over two years of operations in which the trap under test was changed at least 10 times.

  8. Trap Design for Vibratory Bowl Feeders Robert-Paul Berretty

    E-Print Network [OSTI]

    Utrecht, Universiteit

    devices such as wiper blades, grooves and traps. Most of these devices are filters Research is supported

  9. 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

  10. 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

  11. 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.

  12. Light trapping in photonic crystals Ken Xingze Wang,ab

    E-Print Network [OSTI]

    Cui, Yi

    Light trapping in photonic crystals Ken Xingze Wang,ab Zongfu Yu,bc Victor Liu,bd Aaswath Raman,b Yi Cuief and Shanhui Fan*b We consider light trapping in photonic crystals in the weak material-integrated absorption enhancement by light trapping is proportional to the photonic density of states. The tight bound

  13. Commons as insurance: safety nets or poverty traps? Philippe Delacote

    E-Print Network [OSTI]

    Langerhans, Brian

    Commons as insurance: safety nets or poverty traps? Philippe Delacote Economics Department, EUI. The aim of this paper is to consider the potential poverty-trap implications of this use. If the capacity, the introduction of an insurance scheme could be an exit to the poverty trap and relax pressure on the resource

  14. Fluctuation characteristics and transport properties of collisionless trapped electron mode turbulence

    SciTech Connect (OSTI)

    Xiao Yong; Holod, Ihor; Zhang Wenlu; Lin Zhihong [Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States); Klasky, Scott [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    2010-02-15T23:59:59.000Z

    The collisionless trapped electron mode turbulence is investigated by global gyrokinetic particle simulation. The zonal flow dominated by low frequency and short wavelength acts as a very important saturation mechanism. The turbulent eddies are mostly microscopic, but with a significant portion in the mesoscale. The ion heat transport is found to be diffusive and follows the local radial profile of the turbulence intensity. However, the electron heat transport demonstrates some nondiffusive features and only follows the global profile of the turbulence intensity. The nondiffusive features of the electron heat transport is further confirmed by nonlognormal statistics of the flux-surface-averaged electron heat flux. The radial and time correlation functions are calculated to obtain the radial correlation length and autocorrelation time. Characteristic time scale analysis shows that the zonal flow shearing time and eddy turnover time are very close to the effective decorrelation time, which suggests that the trapped electrons move with the fluid eddies. The fluidlike behaviors of the trapped electrons and the persistence of the mesoscale eddies contribute to the transition of the electron turbulent transport from gyro-Bohm scaling to Bohm scaling when the device size decreases.

  15. Energy Efficient Steam Trapping of Trace Heating Systems

    E-Print Network [OSTI]

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

    1981-01-01T23:59:59.000Z

    to insure low back pressure. Caution: Make certain the trap you select can handle the system back pressure. Each trap has specific limitations in this regard. 8. A Y-Strainer is considered mandatory for use on any Tracer Trap to reduce the potential... for plugging based on the small orifice sizes being employed. (Refer to Fig. 3). 9. Freeze-proofing each trap should be in accord with each manufacturer's recommendations. 10. When multiple traps are installed to discharge into a common manifold, check...

  16. 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.

  17. 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.

  18. 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.

  19. 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 fr Plasmaphysik, Boltzmannstrae 2, D-85748 Garching b. Mnchen (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.

  20. 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.

  1. Effect of trapping in degenerate quantum plasmas

    SciTech Connect (OSTI)

    Shah, H. A.; Qureshi, M. N. S. [Department of Physics, GC University, Lahore 54000 (Pakistan); Tsintsadze, N. [Department of Physics, GC University, Lahore 54000 (Pakistan); Salam Chair, GC University, Lahore 54000 (Pakistan)

    2010-03-15T23:59:59.000Z

    In the present work we consider the effect of trapping as a microscopic process in a plasma consisting of quantum electrons and nondegenerate ions. The formation of solitary structures is investigated in two cases: first when the electrons are fully degenerate and second when small temperature effects are taken into account. It is seen that not only rarefactive but coupled rarefactive and compressive solitons are obtained under different temperature conditions.

  2. 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.

  3. Reduce Steam Trap Failures at Chambers Works

    E-Print Network [OSTI]

    Kouba, C.

    2010-01-01T23:59:59.000Z

    automatically within SAP ? Survey performed and work orders created ? Surveyor/Team Leader coordinates repair work ? Use backlog of work to justify number of mechanics ? Prioritize work for mechanics ? Repair Mechanics work across the site ? SAP Work Order... history updated for individual traps ? Surveyor updates excel spreadsheet with repair history ? Monthly reports sent to area and site management 10/20/2010 11Piloted Solution Key Learnings ? SAP Cumbersome and slows repair process ? Use SAP...

  4. Steam Trap Maintenance as a Profit Center

    E-Print Network [OSTI]

    Bouchillon, J. L.

    of the proper piping arrangements to all your basic equipment showing the traps, strainers, air vents, vacuum breakers, etc. These diagrams need to apply only to your plant, not to the hundreds of possibilities found in an all-purpose publication. See Fig... and rust ("dirt") E Size L Mechanical failure usually is... OJ Recommended design factor 2-3 Loud, popping condensate discharge No Renewable wlo piping disassembly No Requires strainer No Tbennal efficiency (low steam loss) Fair Condensate Wscharge...

  5. The relative efficiency of the Malaise trap and animal-baited traps for collecting biting flies in Southwest Texas

    E-Print Network [OSTI]

    Easton, Emmett Richard

    1967-01-01T23:59:59.000Z

    to laboratory animals. A trap model was desired that would require little or no handling of the trapped animal. Disney (1966) placed a metal sheet around a cubical rat cage and liberally applied castor oil to the metal sheet so that phlebotomine sand flies... could be caught and trapped in the castor oil. Since this sand fly moves in a hopping fashion the trap would seem to be more efficient for this fly than for mosquitoes. Bellamy and Res~ca (1952) employed a 110-lb. lard can as a portable baited trap...

  6. Zinc-oxide charge trapping memory cell with ultra-thin chromium-oxide trapping layer

    SciTech Connect (OSTI)

    El-Atab, Nazek; Rizk, Ayman; Nayfeh, Ammar [Institute Center for Microsystems iMicro, Department of Electrical Engineering and Computer Science (EECS), Masdar Institute of Science and Technology Abu Dhabi (United Arab Emirates)] [Institute Center for Microsystems iMicro, Department of Electrical Engineering and Computer Science (EECS), Masdar Institute of Science and Technology Abu Dhabi (United Arab Emirates); Okyay, Ali K. [Department of Electrical and Electronics Engineering, Bilkent University, 06800 Ankara (Turkey) [Department of Electrical and Electronics Engineering, Bilkent University, 06800 Ankara (Turkey); UNAM-National Nanotechnology Research Center and Institute of Materials Science and Nanotechnology, Bilkent University, 06800 Ankara (Turkey)

    2013-11-15T23:59:59.000Z

    A functional zinc-oxide based SONOS memory cell with ultra-thin chromium oxide trapping layer was fabricated. A 5 nm CrO{sub 2} layer is deposited between Atomic Layer Deposition (ALD) steps. A threshold voltage (V{sub t}) shift of 2.6V was achieved with a 10V programming voltage. Also for a 2V V{sub t} shift, the memory with CrO{sub 2} layer has a low programming voltage of 7.2V. Moreover, the deep trapping levels in CrO{sub 2} layer allows for additional scaling of the tunnel oxide due to an increase in the retention time. In addition, the structure was simulated using Physics Based TCAD. The results of the simulation fit very well with the experimental results providing an understanding of the charge trapping and tunneling physics.

  7. 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).

  8. Cooling trapped atoms in optical resonators

    E-Print Network [OSTI]

    Stefano Zippilli; Giovanna Morigi

    2007-03-20T23:59:59.000Z

    We derive an equation for the cooling dynamics of the quantum motion of an atom trapped by an external potential inside an optical resonator. This equation has broad validity and allows us to identify novel regimes where the motion can be efficiently cooled to the potential ground state. Our result shows that the motion is critically affected by quantum correlations induced by the mechanical coupling with the resonator, which may lead to selective suppression of certain transitions for the appropriate parameters regimes, thereby increasing the cooling efficiency.

  9. Parallel ion strings in linear multipole traps

    E-Print Network [OSTI]

    Mathieu Marciante; Caroline Champenois; J. Pedregosa-Gutierrez; Annette Calisti; Martina Knoop

    2011-03-13T23:59:59.000Z

    Additional radio-frequency (rf) potentials applied to linear multipole traps create extra field nodes in the radial plane which allow one to confine single ions, or strings of ions, in totally rf field-free regions. The number of nodes depends on the order of the applied multipole potentials and their relative distance can be easily tuned by the amplitude variation of the applied voltages. Simulations using molecular dynamics show that strings of ions can be laser cooled down to the Doppler limit in all directions of space. Once cooled, organized systems can be moved with very limited heating, even if the cooling process is turned off.

  10. 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.

  11. Measurements of PM 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 DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment3311, 3312), October 20122Technologies |Measurements of PM Traps

  12. Effective Steam Trap Selection/Maintenance - Its Payback

    E-Print Network [OSTI]

    Garcia, E.

    1984-01-01T23:59:59.000Z

    trap location, service, manufacturer, model, steam pressures, pipe size, type of connect ion, associated valves, strainer, and insulation. The condition in which each trap was found in the plant was reported and summarized as in Table 1. Other... leaks and any unsafe situations were also noted. Of the 5,000 surveyed traps, approximately 20% had failed open or were in another failure mode where live steam was leaking, 5% were found plugged, and 10% were found not losing steam but needing...

  13. 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.

  14. 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.

  15. Flow in channels with superhydrophobic trapezoidal textures

    E-Print Network [OSTI]

    Nizkaya, Tatiana V; Vinogradova, Olga I

    2013-01-01T23:59:59.000Z

    Superhydrophobic one-dimensional surfaces reduce drag and generate transverse hydrodynamic phenomena by combining hydrophobicity and roughness to trap gas bubbles in a microscopic textures. Recent work in this area has focused on specific cases of superhydrophobic stripes. Here we study theoretically and numerically the hydrodynamic flow in a channel with a superhydrophobic trapezoidal texture. These allow us to evaluate the drag reduction and anisotropy of the flow for various trapezoidal reliefs. Our results provide a framework for the rational design of superhydrophobic surfaces for microfluidic applications.

  16. 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.

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

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

    extending into the red which results from electron traps on under-coordinated titanium atoms, which are prevalent on (001) facets. The results of this study suggest how...

  18. 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...

  19. ap-8 trapped proton: 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...

  20. 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...

  1. 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...

  2. Wavebreaking and Particle Trapping in Collisionless Plasmas: Final Report

    SciTech Connect (OSTI)

    Shadwick, Bradley A [University of Nebraska-Lincoln

    2013-08-01T23:59:59.000Z

    The final report describing accomplishments in understanding phase-space processes involved in particle trapping and in developing advance numerical models of laser-plasma interactions.

  3. Cooling by Flow Through Narrow Pores W. J. Mullin1

    E-Print Network [OSTI]

    Mullin, William J.

    Cooling by Flow Through Narrow Pores W. J. Mullin1 and Neal Kalechofsky2 1 Physics Department., 130A Baker Avenue, Concord, MA, 01742, USA Abstract. We consider the possibility of cooling 3 He atoms or channels. The proposed method is somewhat analogous to that employed to evaporatively cool trapped gases

  4. Great Lakes Ecosystems Flow of energy through ecosystems; recycling of

    E-Print Network [OSTI]

    Cochran-Stafira, D. Liane

    --> light energy there is a loss of "useful" energy during transformation: heat The sun is the ultimate Sun to producer to consumer to decomposer Solar energy is trapped by photosynthesis as chemical1 Great Lakes Ecosystems Part I Flow of energy through ecosystems; recycling of matter within

  5. Flow chamber

    DOE Patents [OSTI]

    Morozov, Victor (Manassas, VA)

    2011-01-18T23:59:59.000Z

    A flow chamber having a vacuum chamber and a specimen chamber. The specimen chamber may have an opening through which a fluid may be introduced and an opening through which the fluid may exit. The vacuum chamber may have an opening through which contents of the vacuum chamber may be evacuated. A portion of the flow chamber may be flexible, and a vacuum may be used to hold the components of the flow chamber together.

  6. Geological flows

    E-Print Network [OSTI]

    Yu. N. Bratkov

    2008-11-19T23:59:59.000Z

    In this paper geology and planetology are considered using new conceptual basis of high-speed flow dynamics. Recent photo technics allow to see all details of a flow, 'cause the flow is static during very short time interval. On the other hand, maps and images of many planets are accessible. Identity of geological flows and high-speed gas dynamics is demonstrated. There is another time scale, and no more. All results, as far as the concept, are new and belong to the author. No formulae, pictures only.

  7. ORIGINAL PAPER Flow Dynamics and Plasma Heating of Spheromaks in SSX

    E-Print Network [OSTI]

    Brown, Michael R.

    ORIGINAL PAPER Flow Dynamics and Plasma Heating of Spheromaks in SSX M. R. Brown ? C. D. Cothran ? from single dipole- trapped spheromaks and spheromak merging studies at SSX. Single spheromaks) copper flux conserver. Local spheromak flow is studied with two Mach probes (r1 £ qi, r2 qi) calibrated

  8. OPTIMAL CONTROL OF PARTIALLY MISCIBLE TWO-PHASE FLOW WITH APPLICATIONS TO SUBSURFACE CO2 SEQUESTRATION

    E-Print Network [OSTI]

    Ulbrich, Michael

    control problems that are governed by multiphase multicomponent flow in porous media. The concrete in porous media. The objective is, e.g., to maximize the amount of trapped CO2 in an underground reservoir/FV methods for multiphase multicomponent flows in porous media we refer to [11] and references therein

  9. Spacetime near isolated and dynamical trapping horizons

    E-Print Network [OSTI]

    Ivan Booth

    2014-06-02T23:59:59.000Z

    We study the near-horizon spacetime for isolated and dynamical trapping horizons (equivalently marginally outer trapped tubes). The metric is expanded relative to an ingoing Gaussian null coordinate and the terms of that expansion are explicitly calculated to second order. For the spacelike case, knowledge of the intrinsic and extrinsic geometry of the (dynamical) horizon is sufficient to determine the near-horizon spacetime, while for the null case (an isolated horizon) more information is needed. In both cases spacetime is allowed to be of arbitrary dimension and the formalism accomodates both general relativity as well as more general field equations. The formalism is demonstrated for two applications. First, spacetime is considered near an isolated horizon and the construction is both checked against the Kerr-Newman solution and compared to the well-known near-horizon limit for stationary extremal black hole spacetimes. Second, spacetime is examined in the vicinity of a slowly evolving horizon and it is demonstrated that there is always an event horizon candidate in this region. The geometry and other properties of this null surface match those of the slowly evolving horizon to leading order and in this approximation the candidate evolves in a locally determined way. This generalizes known results for Vaidya as well as certain spacetimes known from studies of the fluid-gravity correspondence.

  10. Energy trapping from Hagedorn densities of states

    E-Print Network [OSTI]

    Connor Behan; Klaus Larjo; Nima Lashkari; Brian Swingle; Mark Van Raamsdonk

    2013-04-26T23:59:59.000Z

    In this note, we construct simple stochastic toy models for holographic gauge theories in which distributions of energy on a collection of sites evolve by a master equation with some specified transition rates. We build in only energy conservation, locality, and the standard thermodynamic requirement that all states with a given energy are equally likely in equilibrium. In these models, we investigate the qualitative behavior of the dynamics of the energy distributions for different choices of the density of states for the individual sites. For typical field theory densities of states (\\log(\\rho(E)) ~ E^{\\alphaenergy spread out relatively quickly. For large N gauge theories with gravitational duals, the density of states for a finite volume of field theory degrees of freedom typically includes a Hagedorn regime (\\log(\\rho(E)) ~ E). We find that this gives rise to a trapping of energy in subsets of degrees of freedom for parametrically long time scales before the energy leaks away. We speculate that this Hagedorn trapping may be part of a holographic explanation for long-lived gravitational bound states (black holes) in gravitational theories.

  11. 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

  12. Aqueous carrier waveguide in a flow cytometer

    DOE Patents [OSTI]

    Mariella, R.P. Jr.; Engh, G. van den; Northrup, M.A.

    1995-12-12T23:59:59.000Z

    The liquid of a flow cytometer itself acts as an optical waveguide, thus transmitting the light to an optical filter/detector combination. This alternative apparatus and method for detecting scattered light in a flow cytometer is provided by a device which views and detects the light trapped within the optical waveguide formed by the flow stream. A fiber optic or other light collecting device is positioned within the flow stream. This provides enormous advantages over the standard light collection technique which uses a microscope objective. The signal-to-noise ratio is greatly increased over that for right-angle-scattered light collected by a microscope objective, and the alignment requirements are simplified. 6 figs.

  13. Magnetic multipole induced zero-rotation frequency bounce-resonant loss in a PenningMalmberg trap used for antihydrogen trapping

    E-Print Network [OSTI]

    Wurtele, Jonathan

    Magnetic multipole induced zero-rotation frequency bounce-resonant loss in a PenningMalmberg trap of the antiprotons around the trap axis to pass through zero. In the presence of a transverse magnetic multipole into the trap wall when the trap also employs a magnetic multipole. The multipole's function is to confine H

  14. Fundamental limit of nanophotonic light trapping in solar cells

    E-Print Network [OSTI]

    Fan, Shanhui

    -generation solar cells. The ultimate success of photovoltaic (PV) cell technology requires great advancementsFundamental 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

  15. 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

  16. 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

  17. 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 unit Residual Trapping Sgi Sg,max krg krg Sgt(Soi) Sgt,max Gas Saturation Gas relative Land Model * * ** 1 )( gi gi gigt CS S SS + = Sgf Sg Sgt,max kd rg Sg Gas Saturation

  18. Surface-electrode ion trap with integrated light source

    E-Print Network [OSTI]

    Kim, Tony Hyun

    An atomic ion is trapped at the tip of a single-mode optical fiber in a cryogenic (8 K) surface-electrode ion trap. The fiber serves as an integrated source of laser light, which drives the quadrupolequbit transition of ...

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

    E-Print Network [OSTI]

    Feldman, A. L.

    1981-01-01T23:59:59.000Z

    With rising steam costs and a high failure rate on the Joliet Plants standard steam trap, a testing and evaluation program was begun to find a steam trap that would work at Olin-Joliet. The basis was to conduct the test on the actual process...

  20. 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

  1. Simulations of plasma confinement in an antihydrogen trap

    SciTech Connect (OSTI)

    Gomberoff, K.; Fajans, J.; Friedman, A.; Grote, D.; Vay, J.-L.; Wurtele, J.S.

    2007-10-15T23:59:59.000Z

    The three-dimensional particle-in-cell (3-D PIC) simulation code WARP is used to study positron confinement in antihydrogen traps. The magnetic geometry is close to that of a UC Berkeley experiment conducted, with electrons, as part of the ALPHA collaboration (W. Bertsche et al., AIP Conf. Proc. 796, 301 (2005)). In order to trap antihydrogen atoms, multipole magnetic fields are added to a conventional Malmberg-Penning trap. These multipole fields must be strong enough to confine the antihydrogen, leading to multipole field strengths at the trap wall comparable to those of the axial magnetic field. Numerical simulations reported here confirm recent experimental measurements of reduced particle confinement when a quadrupole field is added to a Malmberg-Penning trap. It is shown that, for parameters relevant to various antihydrogen experiments, the use of an octupole field significantly reducesthe positron losses seen with a quadrupole field. A unique method for obtaining a 3-D equilibrium of the positrons in the trap with a collisionless PIC code was developed especially for the study of the antihydrogen trap; however, it is of practical use for other traps as well.

  2. Hydrodynamic trapping in Mission Canyon Formation (Mississippian) reservoirs: Elkhorn Ranch field, North Dakota

    SciTech Connect (OSTI)

    Demis, W.D. (Marathon Oil Co., Houston, TX (United States))

    1991-03-01T23:59:59.000Z

    Hydrocarbons in Mission Canyon dolomite reservoirs in the Elkhorn Ranch field are trapped by downdip flow of formation water to the northeast. Elkhorn Ranch field is located on a north-plunging anticline with only 10 ft (3 m) of crestal closure. The Mission Canyon is a regressive, shallowing upward sequence of subtidal dolomitized mudstones and wackestones grading upward into sebkha-salina evaporites. Mission Canyon oil production is localized on the north and northeast side of the structure. Maps of porosity pinch-outs and permeability barriers defined from core data, superimposed upon the Mission Canyon structure, show that most of the oil cannot be trapped by stratigraphic facies change. Southwest-trending, updip porosity pinch-outs cross the north-plunging structural axis at an angle so low that hydrocarbons would leak out to the southwest under hydrostatic conditions. Downdip hydrodynamic flow to the northeast provides the critical trapping component. Regional maps of apparent formation water resistivity and water salinity show a region of fresher water south and southwest of the field. A regional potentiometric map constructed using Horner-plot extrapolated shut-in pressure data indicates a head gradient of about 20 ft/mi (4 m/km) to the northeast at Elkhorn Ranch field. This gradient corresponds to a calculated water-oil tilt of about 50 ft/mi (20 m/km). Observed tilt of the oil accumulation is actually about 25 ft/mi (5 m/km) to the northeast. This discrepancy might be the result of the field having not yet reached equilibrium with the invading water.

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

    E-Print Network [OSTI]

    Daniilidis, N.

    We report heating rate measurements in a microfabricated gold-on-sapphire surface electrode ion trap with a trapping height of approximately 240 ?m. Using the Doppler recooling method, we characterize the trap heating rates ...

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. Synergies of High-Efficiency Clean Combustion and Lean NOx Trap...

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

    Synergies of High-Efficiency Clean Combustion and Lean NOx Trap Catalysts Synergies of High-Efficiency Clean Combustion and Lean NOx Trap Catalysts investigation of potential...

  9. Nanoscale interfacial structure for Novel Opto-electronic and Ion-trapping Devices

    E-Print Network [OSTI]

    Ulin-Avila, Erick

    2013-01-01T23:59:59.000Z

    SEM pictures of Aluminum alloy trap A,B. ) trap details C. )including Graphene, Aluminum alloys, Copper, Gold andwe use an specific aluminum alloy, which annealed increases

  10. 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.

  11. 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.

  12. Cooling Flows or Heating Flows?

    E-Print Network [OSTI]

    James Binney

    2003-10-08T23:59:59.000Z

    It is now clear that AGN heat cooling flows, largely by driving winds. The winds may contain a relativistic component that generates powerful synchrotron radiation, but it is not clear that all winds do so. The spatial and temporal stability of the AGN/cooling flow interaction are discussed. Collimation of the winds probably provides spatial stability. Temporal stability may be possible only for black holes with masses above a critical value. Both the failure of cooling flows to have adiabatic cores and the existence of X-ray cavities confirm the importance of collimated outflows. I quantify the scale of the convective flow that the AGN Hydra would need to drive if it balanced radiative inward flow by outward flow parallel to the jets. At least in Virgo any such flow must be confined to r<~20 kpc. Hydrodynamical simulations suggest that AGN outbursts cannot last longer than ~25 Myr. Data for four clusters with well studied X-ray cavities suggests that heating associated with cavity formation approximately balances radiative cooling. The role of cosmic infall and the mechanism of filament formation are briefly touched on.

  13. Stability and dynamics of ion rings in linear multipole traps

    E-Print Network [OSTI]

    Florian Cartarius; Cecilia Cormick; Giovanna Morigi

    2013-01-10T23:59:59.000Z

    Trapped singly-charged ions can crystallize as a result of laser cooling. The emerging structure depends on the number of particles and on the geometry of the trapping potential. In linear multipole radiofrequency traps, the geometry of the radial potential can lead to the formation of single-ring structures. We analyse the conditions and stability of single rings as a function of the number of poles. For larger numbers of ions the rings form tubes in which the arrangement of the ions corresponds to a triangular lattice folded onto a cylinder. The stability of these tubular structures is numerically studied for different lattice constants and their normal mode spectrum is determined.

  14. Commissioning of the Francium Trapping Facility at TRIUMF

    E-Print Network [OSTI]

    M. Tandecki; J. Zhang; R. Collister; S. Aubin; J. A. Behr; E. Gomez; G. Gwinner; L. A. Orozco; M. R. Pearson

    2013-12-12T23:59:59.000Z

    We report on the successful commissioning of the Francium Trapping Facility at TRIUMF. Large laser-cooled samples of francium are produced from a francium ion beam delivered by the ISAC radioactive ion beam facility. The ion beam is neutralized on an yttrium foil, which is subsequently heated to transfer the atoms into the magneto-optical trapping region. We have successfully trapped $^{207}$Fr, $^{209}$Fr and $^{221}$Fr, with a maximum of $2.5 \\times 10^5$ $^{209}$Fr atoms. The neutral cold atoms will be used in studies of the weak interaction through measurements of atomic parity non-conservation.

  15. 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.

  16. Quantum information processing with trapped electrons and superconducting electronics

    E-Print Network [OSTI]

    Nikos Daniilidis; Dylan J Gorman; Lin Tian; Hartmut Hffner

    2013-04-17T23:59:59.000Z

    We describe a parametric frequency conversion scheme for trapped charged particles which enables a coherent interface between atomic and solid-state quantum systems. The scheme uses geometric non-linearities of the potential of a coupling electrode near a trapped particle. Our scheme does not rely on actively driven solid-state devices, and is hence largely immune to noise in such devices. We present a toolbox which can be used to build electron-based quantum information processing platforms, as well as quantum interfaces between trapped electrons and superconducting electronics.

  17. Pressure grouting of fractured basalt flows

    SciTech Connect (OSTI)

    Shaw, P.; Weidner, J.; Phillips, S.; Alexander, J.

    1996-04-01T23:59:59.000Z

    This report describes a field trial of pressure grouting in basalt and the results of subsequent coring and permeability measurement activities. The objective was to show that the hydraulic conductivity of fractured basalt bedrock can be significantly reduced by pressure injection of cementitious materials. The effectiveness of the pressure grout procedure was evaluated by measuring the change in the hydraulic conductivity of the bedrock. The extent of grout penetration was established by analyzing postgrout injection drilling chips for the presence of a tracer in the grout and also by examining cores of the treated basalt. Downhole radar mapping was used to establish major lava flow patterns and follow water movement during a surface infiltration test. A site called Box Canyon, which is located northwest of the INEL, was chosen for this study due to the similarity of this surface outcrop geology to that of the underlying bedrock fracture system found at the Radioactive Waste Management Complex. This study showed that hydraulic conductivity of basalt can be reduced through pressure grouting of cementitious material.

  18. Flow and axial dispersion in a sinusoidal-walled tube: Effects of inertial and unsteady flows

    SciTech Connect (OSTI)

    Richmond, Marshall C.; Perkins, William A.; Scheibe, Timothy D.; Lambert, Adam; Wood, Brian D.

    2013-12-01T23:59:59.000Z

    Dispersion in porous media flows has been the subject of much experimental, theoretical and numerical study. Here we consider a wavy-walled tube (a three-dimensional tube with sinusoidally-varying diameter) as a simplified conceptualization of flow in porous media, where constrictions represent pore throats and expansions pore bodies. A theoretical model for effective (macroscopic) longitudinal dispersion in this system has been developed by volume averaging the microscale velocity field. Direct numerical simulation using computational fluid dynamics (CFD) methods was used to compute velocity fields by solving the Navier-Stokes equations, and also to numerically solve the volume averaging closure problem, for a range of Reynolds numbers (Re) spanning the low-Re to inertial flow regimes, including one simulation at Re = 449 for which unsteady flow was observed. Dispersion values were computed using both the volume averaging solution and a random walk particle tracking method, and results of the two methods were shown to be consistent. Our results are compared to experimental measurements of dispersion in porous media and to previous theoretical results for the low-Re, Stokes flow regime. In the steady inertial regime we observe an power-law increase in effective longitudinal dispersion (DL) with Re, consistent with previous results. This rapid rate of increase is caused by trapping of solute in expansions due to flow separation (eddies). For the unsteady case (Re = 449), the rate of increase of DL with Re was smaller than that observed at lower Re. Velocity fluctuations in this regime lead to increased rates of solute mass transfer between the core flow and separated flow regions, thus diminishing the amount of tailing caused by solute trapping in eddies and thereby reducing longitudinal dispersion.

  19. ablation 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 15...

  20. 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...

  1. acoustic waves trapped: Topics by E-print Network

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

    in a magnetoplasma with a pair of trapped ions CERN Preprints Summary: The nonlinear propagation of dust-acoustic (DA) waves in a magnetized dusty plasma with a pair of...

  2. 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 ...

  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. The Release of Trapped Gases from Amorphous Solid Water Films...

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

    I. Top-Down" Crystallization-Induced Crack Propagation Probed The Release of Trapped Gases from Amorphous Solid Water Films: I. Top-Down" Crystallization-Induced Crack Propagation...

  5. Coherent control of a qubit is trap-free

    E-Print Network [OSTI]

    Alexander Pechen; Nikolay Il'in

    2014-07-19T23:59:59.000Z

    There is a strong interest in optimal manipulating of quantum systems by external controls. Traps are controls which are optimal only locally but not globally. If they exist, they can be serious obstacles to the search of globally optimal controls in numerical and laboratory experiments, and for this reason the analysis of traps attracts considerable attention. In this paper we prove that for a wide range of control problems for two-level quantum systems all locally optimal controls are also globally optimal. Hence we conclude that two-level systems in general are trap-free. In particular, manipulating qubits---two-level quantum systems forming a basic building block for quantum computation---is free of traps for fundamental problems such as the state preparation and gate generation.

  6. Lean NOx Trap Regeneration Selectivity Towards N2O -- Similarities...

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

    Regeneration Selectivity Towards N2O -- Similarities and Differences Between H2, CO and C3H6 Reductants Lean NOx Trap Regeneration Selectivity Towards N2O -- Similarities and...

  7. Time-optimal controls for frictionless cooling in harmonic traps

    E-Print Network [OSTI]

    Salamon, Peter

    OFFPRINT Time-optimal controls for frictionless cooling in harmonic traps K. H. Hoffmann, P payment Details on preparing, submitting and tracking the progress of your manuscript from submission

  8. 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.

  9. 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

  10. 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) ...

  11. Electron source for a mini ion trap mass spectrometer

    DOE Patents [OSTI]

    Dietrich, D.D.; Keville, R.F.

    1995-12-19T23:59:59.000Z

    An ion trap is described which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10{sup 9} and commercial mass spectrometers requiring 10{sup 4} ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products. 10 figs.

  12. Electron source for a mini ion trap mass spectrometer

    DOE Patents [OSTI]

    Dietrich, Daniel D. (Livermore, CA); Keville, Robert F. (Valley Springs, CA)

    1995-01-01T23:59:59.000Z

    An ion trap which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10.sup.9 and commercial mass spectrometers requiring 10.sup.4 ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products.

  13. 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 ...

  14. 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 nanospherederale de Lausanne (EPFL), Institute of Microengineering (IMT), Photovoltaics and Thin Film Electronics, photovoltaics, resonant dielectric structures, solar cells * Corresponding author: e-mail jgrandid

  15. 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 ...

  16. 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.

  17. 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.

  18. 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.

  19. What To Do With Cold Traps and Why

    E-Print Network [OSTI]

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

    2012-01-01T23:59:59.000Z

    . Individual CDL often consist of up to a full-size tee on a distribution line, inlet strainer, isolation valves, steam trap, check valve, mud leg, blowdown valve, bypass line, tagging, and pipe insulation. The initial cost for designing and installing... or resource to periodically blow down strainers / drip pockets? 14. Is there a ?one size fits all? approach towards steam trap selection; using the same model for all drip and tracer applications? 15. Does the site remove strainer screens from steam...

  20. Optical Trapping and Control of a Nanowire by a Nanoaperture

    E-Print Network [OSTI]

    Aporvari, Mehdi Shafiei; Volpe, Giovanni

    2015-01-01T23:59:59.000Z

    We demonstrate that a single sub-wavelength nanoaperture in a metallic thin film can be used to achieve dynamic optical trapping and control of a single dielectric nanowire. A nanoaperture can trap a nanowire, control its orientation when illuminated by a linearly-polarized incident field, and also rotate the nanowire when illuminated by a circularly-polarized incident field. Compared to other designs, this approach has the advantages of a low-power driving field entailing low heating and photodamage.

  1. 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.

  2. 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.

  3. 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

  4. 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

  5. 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.

  6. 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.

  7. Combined U-Th/He and 40Ar/39Ar geochronology of post-shield lavas from the Mauna Kea and Kohala volcanoes, Hawaii

    SciTech Connect (OSTI)

    Aciego, S.M.; Jourdan, F.; DePaolo, D.J.; Kennedy, B.M.; Renne, P.R.; Sims, K.W.W.

    2009-10-01T23:59:59.000Z

    Late Quaternary, post-shield lavas from the Mauna Kea and Kohala volcanoes on the Big Island of Hawaii have been dated using the {sup 40}Ar/{sup 39}Ar and U-Th/He methods. The objective of the study is to compare the recently demonstrated U-Th/He age method, which uses basaltic olivine phenocrysts, with {sup 40}Ar/{sup 39}Ar ages measured on groundmass from the same samples. As a corollary, the age data also increase the precision of the chronology of volcanism on the Big Island. For the U-Th/He ages, U, Th and He concentrations and isotopes were measured to account for U-series disequilibrium and initial He. Single analyses U-Th/He ages for Hamakua lavas from Mauna Kea are 87 {+-} 40 ka to 119 {+-} 23 ka (2{sigma} uncertainties), which are in general equal to or younger than {sup 40}Ar/{sup 39}Ar ages. Basalt from the Polulu sequence on Kohala gives a U-Th/He age of 354 {+-} 54 ka and a {sup 40}Ar/{sup 39}Ar age of 450 {+-} 40 ka. All of the U-Th/He ages, and all but one spurious {sup 40}Ar/{sup 39}Ar ages conform to the previously proposed stratigraphy and published {sup 14}C and K-Ar ages. The ages also compare favorably to U-Th whole rock-olivine ages calculated from {sup 238}U - {sup 230}Th disequilibria. The U-Th/He and {sup 40}Ar/{sup 39}Ar results agree best where there is a relatively large amount of radiogenic {sup 40}Ar (>10%), and where the {sup 40}Ar/{sup 36}Ar intercept calculated from the Ar isochron diagram is close to the atmospheric value. In two cases, it is not clear why U-Th/He and {sup 40}Ar/{sup 39}Ar ages do not agree within uncertainty. U-Th/He and {sup 40}Ar/{sup 39}Ar results diverge the most on a low-K transitional tholeiitic basalt with abundant olivine. For the most alkalic basalts with negligible olivine phenocrysts, U-Th/He ages were unattainable while {sup 40}Ar/{sup 39}Ar results provide good precision even on ages as low as 19 {+-} 4 ka. Hence, the strengths and weaknesses of the U-Th/He and {sup 40}Ar/{sup 39}Ar methods are complimentary for basalts with ages of order 100-500 ka.

  8. 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.

  9. 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

    2012-10-23T23:59:59.000Z

    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.

  10. The Laser Ion Source Trap (LIST) coupled to a gas cell catcher

    E-Print Network [OSTI]

    T. Sonoda; T. E. Cocolios; J. Gentens; M. Huyse; O. Ivanov; Yu. Kudryavtsev; D. Pauwels; P. Van den Bergh; P. Van Duppen

    2009-06-18T23:59:59.000Z

    The proof of principle of the Laser Ion Source Trap (LIST) coupled to a gas cell catcher system has been demonstrated at the Leuven Isotope Separator On-Line (LISOL). The experiments were carried out by using the modified gas cell-based laser ion source and the SextuPole Ion Guide (SPIG). Element selective resonance laser ionization of neutral atoms was taking place inside the cold jet expanding out of the gas cell catcher. The laser path was oriented in longitudinal as well as transverse geometries with respect to the atoms flow. The enhancement of beam purity and the feasibility for in-source laser spectroscopy were investigated in off-line and on-line conditions.

  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. Effect of molybdenum plus chromium on the corrosion of iron-, nickel-, and cobalt-base alloys in basaltic lava and simulated magmatic gas at 1150/sup 0/C

    SciTech Connect (OSTI)

    Ehrlich, S.A.; Douglass, D.L.

    1982-06-01T23:59:59.000Z

    The compatibility of several binary and ternary alloys in a magma environment was studied. Binary alloys containing molybdenum and ternary alloys containing chromium and molybdenum were exposed to basaltic lava at 1150/sup 0/C for periods of 24 and 96 hours. A cover gas was used to produce oxygen and sulfur fugacities corresponding to those of the gases dissolved in basaltic melts. Three base metals were used. These included iron, nickel, and cobalt. The primary reactions in binary alloys were found to be sulfidation. Oxide scales with a spinel layer formed on ternary alloys. The synergistic effect of molybdenum and chromium additions in ternary alloys exhibited superior corrosion resistance to binary alloys which formed base-metal sulfides down grain-boundaries. Extensive analyses of the reaction products by scanning electron microscopy, X-ray energy dispersive analysis, electron microprobe analysis, and metallography are presented for each alloys. The products formed are discussed with reference to thermodynamic stability diagrams, and the reaction path concept is used to explain some of the corrosion.

  13. 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.

  14. A simple segregated flow model for a WAG process

    E-Print Network [OSTI]

    Hopkins, Christopher Wright

    1985-01-01T23:59:59.000Z

    integration, a volumetric balance of the injectants and the initial reservoir fluids is obtained. The model was developed with several simplifying assumptions including immiscible water and gas phases, incompressible fluid f'low, no trapped oil volumes... with the process are the relatively higher sweep efficiencies of water floods and the low residual oil saturations of miscible gas injection. The mechanism oP water flooding is generally well understood. Many Pields have been and still are being waterflooded...

  15. 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.

  16. 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.

  17. Plasma-beam traps and radiofrequency quadrupole beam coolers

    SciTech Connect (OSTI)

    Maggiore, M., E-mail: mario.maggiore@lnl.infn.it; Cavenago, M.; Comunian, M.; Chirulotto, F.; Galat, A.; De Lazzari, M.; Porcellato, A. M.; Roncolato, C.; Stark, S. [INFN-LNL, viale dellUniversit 2, 35020 Legnaro (Italy)] [INFN-LNL, viale dellUniversit 2, 35020 Legnaro (Italy); Caruso, A.; Longhitano, A. [INFN-LNS, via S. Sofia 54, 95123 Catania (Italy)] [INFN-LNS, via S. Sofia 54, 95123 Catania (Italy); Cavaliere, F.; Maero, G.; Paroli, B.; Pozzoli, R.; Rom, M. [INFN Sezione di Milano and Dipartimento di Fisica, Universit degli Studi di Milano, via Celoria 16, 20133 Milano (Italy)] [INFN Sezione di Milano and Dipartimento di Fisica, Universit degli Studi di Milano, via Celoria 16, 20133 Milano (Italy)

    2014-02-15T23:59:59.000Z

    Two linear trap devices for particle beam manipulation (including emittance reduction, cooling, control of instabilities, dust dynamics, and non-neutral plasmas) are here presented, namely, a radiofrequency quadrupole (RFQ) beam cooler and a compact Penning trap with a dust injector. Both beam dynamics studies by means of dedicated codes including the interaction of the ions with a buffer gas (up to 3 Pa pressure), and the electromagnetic design of the RFQ beam cooler are reported. The compact multipurpose Penning trap is aimed to the study of multispecies charged particle samples, primarily electron beams interacting with a background gas and/or a micrometric dust contaminant. Using a 0.9 T solenoid and an electrode stack where both static and RF electric fields can be applied, both beam transport and confinement operations will be available. The design of the apparatus is presented.

  18. Scalable Digital Hardware for a Trapped Ion Quantum Computer

    E-Print Network [OSTI]

    Mount, Emily; Vrijsen, Geert; Adams, Michael; Baek, So-Young; Hudek, Kai; Isabella, Louis; Crain, Stephen; van Rynbach, Andre; Maunz, Peter; Kim, Jungsang

    2015-01-01T23:59:59.000Z

    Many of the challenges of scaling quantum computer hardware lie at the interface between the qubits and the classical control signals used to manipulate them. Modular ion trap quantum computer architectures address scalability by constructing individual quantum processors interconnected via a network of quantum communication channels. Successful operation of such quantum hardware requires a fully programmable classical control system capable of frequency stabilizing the continuous wave lasers necessary for trapping and cooling the ion qubits, stabilizing the optical frequency combs used to drive logic gate operations on the ion qubits, providing a large number of analog voltage sources to drive the trap electrodes, and a scheme for maintaining phase coherence among all the controllers that manipulate the qubits. In this work, we describe scalable solutions to these hardware development challenges.

  19. 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.

  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. 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.

  2. Interface-trap charge-pump temperature sensor

    E-Print Network [OSTI]

    Sharifi, Reza

    2001-01-01T23:59:59.000Z

    and connections. If the source is kept at a constant voltage to allow the area underneath the gate to move between inversion and accumulation the following relations must hold: VGP & VFB+ VW Voa ? Vs & Vr (2) Where VFs is flat band voltage, Vr is Threshold... occupied energy level in conduction band corresponds to free electron energy. These two bands are separated by bandgap where traps energy levels are located. The density of traps in the bandgap is a process dependent quality. vo vw Source vs N (well...

  3. 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.

  4. Use of a Novel Fluidics Microbead Trap/Flow-cell Enhances Speed...

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

    Sensitivity of Bead-Based Bioassays."JALA. Journal of the Association for Laboratory Automation 12(5):303-310. doi:10.1016j.jala.2007.05.002 Authors: RM Ozanich KC Antolick CJ...

  5. Hydrogen and helium entrapment in flowing liquid metal plasma-facing surfaces

    E-Print Network [OSTI]

    Harilal, S. S.

    Hydrogen and helium entrapment in flowing liquid metal plasma-facing surfaces Ahmed Hassanein the PFC surface (helium and hydrogen isotopes) while accommodating high heat loads. To study this problem. Hydrogen isotope (DT) particles are likely be trapped in the liquid metal surface (e.g., lithium) due

  6. Recurrent Shocks, Poverty Traps and the Degradation of the Social Capital Base of Pastoralism: A Case Study from Southern Ethiopia

    E-Print Network [OSTI]

    Berhanu, Wassie

    2009-01-01T23:59:59.000Z

    2009 Recurrent Shocks, Poverty Traps and the Degradation of2009) Recurrent Shocks, Poverty Traps and the Degradation ofMay J, 2006. Exploring Poverty Traps and Social Exclusion in

  7. 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 ...

  8. Combining Low-Temperature Combustion with Lean-NOx Trap Yields...

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

    Low-Temperature Combustion with Lean-NOx Trap Yields Progress Toward Targets of Efficient NOx Control for Diesels Combining Low-Temperature Combustion with Lean-NOx Trap Yields...

  9. 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...

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

  11. Design of superconducting transmission line integrated surface-electrode ion-traps

    E-Print Network [OSTI]

    Meyer, David Thomas

    2011-01-01T23:59:59.000Z

    We fabricated superconducting surface electrode ion traps with integrated microwave coplanar waveguides using direct-write optical lithography and a niobium on sapphire process. We then tested these traps in a closed cycle ...

  12. Trapping capacity of fault zones, downdip Yegua Formation, Texas Gulf Coast basin

    E-Print Network [OSTI]

    Hintz, Jena Christine

    2001-01-01T23:59:59.000Z

    The homogenization of sediment from shearing forms traps in both the hanging wall and footwall due to capillary pressure differences. The sheared zone associated with large faults can form traps. Sheared zones associated ...

  13. 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.

  14. Coronal Trapping of Energetic Flare Particles: Yohkoh/HXT Observations

    E-Print Network [OSTI]

    Metcalf, Thomas R.

    the energization of the solar corona. The most common interpretation for the production of the observed HXR fluxes Alexander Lockheed Martin Solar and Astrophysics Laboratory, Department H1­12, Bldg. 252, 3251 Hanover St in a search for spectral evidence of the coronal trapping of energetic particles during solar flares. Two

  15. 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

  16. Steam Traps-The Oft Forgotten Energy Conservation Treasure

    E-Print Network [OSTI]

    Pychewicz, F. S.

    on the part of several vendors to design trap internals to our specifications; namely, a thermostatic bellows with a restricted orifice (5/64") and an internal strainer screen. Another criteria was a fail closed design. The vendors primarily feared use...

  17. Progress in year 1995 1. Optically plugged magnetic quadrupole trap

    E-Print Network [OSTI]

    Progress in year 1995 1. Optically plugged magnetic quadrupole trap In 1995, we have demonstrated samples of ultracold atoms at unprecedented densities (>1014 cm-3) and to evaporatively cool atoms to Bose Dressed-StateEnergyMagneticField Atoms During evaporative cooling, the cloud shrunk and finally split up

  18. 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 Lpez-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\

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

    E-Print Network [OSTI]

    van Rooij, Robert

    and by improving their photovoltaic conversion efficiency. For Si solar cells, both challenges can be achievedLight Trapping in Solar Cells Using Resonant Nanostructures P. Spinelli #12;Summary Photovoltaics of energy for our society. In order for this to happen, photovoltaics needs to be economically competitive

  20. Radiation trapping in a cold atomic gas Guillaume Labeyrie,1

    E-Print Network [OSTI]

    field of study deals with the transport of near resonant light in such media. Using cold atoms, one can at the end of the 20th century that studies of light transport in optically thick clouds of cold atomsRadiation trapping in a cold atomic gas Guillaume Labeyrie,1 Robin Kaiser,1, and Dominique Delande

  1. 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@stanford.edu Abstract: Organic bulk heterojunction solar cells are a promising candidate for low-cost next lying on top of the organic solar cell stack produce a 8-15% increase in photocurrent for a model

  2. Towards electron-electron entanglement in Penning traps

    E-Print Network [OSTI]

    L. Lamata; D. Porras; J. I. Cirac; J. Goldman; G. Gabrielse

    2010-02-05T23:59:59.000Z

    Entanglement of isolated elementary particles other than photons has not yet been achieved. We show how building blocks demonstrated with one trapped electron might be used to make a model system and method for entangling two electrons. Applications are then considered, including two-qubit gates and more precise quantum metrology protocols.

  3. Theory and Simulation of Neoclassical Transport Processes, with Local Trapping

    E-Print Network [OSTI]

    California at San Diego, University of

    Theory and Simulation of Neoclassical Transport Processes, with Local Trapping Daniel H. E. Dubin of a plasma with static electric and/or magnetic fields are of central importance in plasma theory and experiment. For exam- ple, in the theory of neoclassical transport, a magnetically confined plasma interacts

  4. Simulation of lean NOx trap performance with microkinetic chemistry and without mass transfer.

    SciTech Connect (OSTI)

    Larson, Rich; Daw, C. Stuart (Oak Ridge National Laboratory, Knoxville, TN); Pihl, Josh A. (Oak Ridge National Laboratory, Knoxville, TN); Chakravarthy, V. Kalyana (Oak Ridge National Laboratory, Knoxville, TN)

    2011-08-01T23:59:59.000Z

    A microkinetic chemical reaction mechanism capable of describing both the storage and regeneration processes in a fully formulated lean NO{sub x} trap (LNT) is presented. The mechanism includes steps occurring on the precious metal, barium oxide (NO{sub x} storage), and cerium oxide (oxygen storage) sites of the catalyst. The complete reaction set is used in conjunction with a transient plug flow reactor code to simulate not only conventional storage/regeneration cycles with a CO/H{sub 2} reductant, but also steady flow temperature sweep experiments that were previously analyzed with just a precious metal mechanism and a steady state code. The results show that NO{sub x} storage is not negligible during some of the temperature ramps, necessitating a re-evaluation of the precious metal kinetic parameters. The parameters for the entire mechanism are inferred by finding the best overall fit to the complete set of experiments. Rigorous thermodynamic consistency is enforced for parallel reaction pathways and with respect to known data for all of the gas phase species involved. It is found that, with a few minor exceptions, all of the basic experimental observations can be reproduced with these purely kinetic simulations, i.e., without including mass-transfer limitations. In addition to accounting for normal cycling behavior, the final mechanism should provide a starting point for the description of further LNT phenomena such as desulfation and the role of alternative reductants.

  5. On the Design of Traps for Feeding 3D Parts on Vibratory Tracks

    E-Print Network [OSTI]

    Utrecht, Universiteit

    a sequence of mechanical devices such as wiper blades, grooves and traps. Most of these devices are filters

  6. Minimal Trap Design Pankaj K. Agarwal, Anne D. Collinsy, and John L. Harerz

    E-Print Network [OSTI]

    Agarwal, Pankaj K.

    ].) Along this track is placed a sequence of obstacles (ramps, wiper blades, traps, etc.) designed to allow

  7. Trap Design for Vibratory Bowl Feeders # RobertPaul Berretty +# Ken Goldberg Mark H. Overmars +

    E-Print Network [OSTI]

    Utrecht, Universiteit

    devices such as wiper blades, grooves and traps. Most of these devices are filters # Research is supported

  8. Planetary magnetism : investigations of paleomagnetic properties of the Earth and Moon

    E-Print Network [OSTI]

    Lawrence, Kristin Portle

    2008-01-01T23:59:59.000Z

    del Lago Buenos Aires, Patagonia, Geochemistry Geophysicsaveraged field in southern Patagonia recorded in lava flows,

  9. Waveguide detection of right-angle-scattered light in flow cytometry

    DOE Patents [OSTI]

    Mariella, Jr., Raymond P. (Danville, CA)

    2000-01-01T23:59:59.000Z

    A transparent flow cell is used as an index-guided optical waveguide. A detector for the flow cell but not the liquid stream detects the Right-Angle-Scattered (RAS) Light exiting from one end of the flow cell. The detector(s) could view the trapped RAS light from the flow cell either directly or through intermediate optical light guides. If the light exits one end of the flow cell, then the other end of the flow cell can be given a high-reflectivity coating to approximately double the amount of light collected. This system is more robust in its alignment than the traditional flow cytometry systems which use imaging optics, such as microscope objectives.

  10. Low volume flow meter

    DOE Patents [OSTI]

    Meixler, Lewis D. (East Windsor, NJ)

    1993-01-01T23:59:59.000Z

    The low flow monitor provides a means for determining if a fluid flow meets a minimum threshold level of flow. The low flow monitor operates with a minimum of intrusion by the flow detection device into the flow. The electrical portion of the monitor is externally located with respect to the fluid stream which allows for repairs to the monitor without disrupting the flow. The electronics provide for the adjustment of the threshold level to meet the required conditions. The apparatus can be modified to provide an upper limit to the flow monitor by providing for a parallel electronic circuit which provides for a bracketing of the desired flow rate.

  11. Characteristics of Pt-K/MgAl2O4 lean NOx trap catalysts. | EMSL

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

    Pt-KMgAl2O4 lean NOx trap catalysts. Characteristics of Pt-KMgAl2O4 lean NOx trap catalysts. Abstract: We report the various characteristics of Pt-KMgAl2O4 lean NOx trap (LNT)...

  12. 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

  13. A Double Ion Trap for Large Coulomb Crystals Caroline Champenois, Jofre Pedregosa-Gutierrez, Mathieu Marciante,

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    : 37.10.Ty; 52.25.Kn;52.27.Jt MULTIPOLE TRAPS Thirty years after Wolfgang Paul's introduction of the 3D, the multipole trap is combined in line with a quadrupole trap, using a shuttling protocol between both parts

  14. DISSERTATION THE EFFECT OF TRAPPING DEFECTS ON CIGS SOLAR-CELL

    E-Print Network [OSTI]

    Sites, James R.

    DISSERTATION THE EFFECT OF TRAPPING DEFECTS ON CIGS SOLAR-CELL PERFORMANCE Submitted by Pamela K ENTITLED THE EFFECT OF TRAPPING DEFECTS ON CIGS SOLAR-CELL PERFORMANCE BE ACCEPTED AS FULFILLING IN PART RE OF DISSERTATION THE EFFECT OF TRAPPING DEFECTS ON CIGS SOLAR-CELL PERFORMANCE The relationship between basic solar-cell

  15. Cooling and Heating of the Quantum Motion of Trapped Cd+ Louis Deslauriers

    E-Print Network [OSTI]

    Monroe, Christopher

    ABSTRACT Cooling and Heating of the Quantum Motion of Trapped Cd+ Ions by Louis Deslauriers Chair information processor has seen tremendous progress in many fields of physics. In the last decade, trapped ions for entanglement generation limiting the fidelity of quantum logic gates. Effective ground state cooling of trapped

  16. Future works The Ion trap -Laser cooling technique has the ad-

    E-Print Network [OSTI]

    Hensinger, Winfried

    Future works The Ion trap - Laser cooling technique has the ad- vantages to easily manipulate apparatus for trace isotope analysis. Guidance of the ion beams to the trap Laser cooling of ions with this apparatus Realization of trapping ions from ICP-MS Optimization of the experimental system for detecting

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

    E-Print Network [OSTI]

    Fan, Shanhui

    trapping results in a thinner active region in a solar cell, which lowers the pro- duction cost by reducingAngular 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

  18. Light traps are one of a number of different gears used to sample

    E-Print Network [OSTI]

    438 Light traps are one of a number of different gears used to sample pelagic larval and juvenile fishes. In contrast to conventional towed nets, light traps primarily collect larger size classes and Cowen, 1996; Wilson, 2001). The relative ease with which multiple synoptic light trap samples can

  19. Academy of Natural Sciences An Effective Trapping and Marking Method for Aquatic Beetles

    E-Print Network [OSTI]

    Aiken, Ron

    suffer from one or more deficiencies. Glass bottles are heavy, awkwardto store and subject to vandalismin, Hydradephaga,marking, trapping] The first discussion of bottle traps used to studyaquaticbeetlesin North trapand a varietyof othersam- pling devices used in his studies in California ponds. His bottle trap

  20. 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

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

    E-Print Network [OSTI]

    Bandyopadhyay, Antar

    of poverty trap is synonymous to getting loan from the formal sector. The MFI discipline the borrower to saveEfficient 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

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

    E-Print Network [OSTI]

    Paris-Sud XI, Universit 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

  3. 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. Mnica 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

  4. 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

  5. Laser Stabilization for Quantum Computing with Trapped Barium ions Corey Adams

    E-Print Network [OSTI]

    Blinov, Boris

    system used to trap and cool Ba+ ions used for quantum computation research. The lasers, at 650 and 985 perform ex- periments, including trapping ions themselves. A trap works using both a laser cooling system in the cooling system is important to its success. A proposed method to stabilize lasers is to use an external

  6. Bacteria in shear flow

    E-Print Network [OSTI]

    Marcos, Ph.D. Massachusetts Institute of Technology

    2011-01-01T23:59:59.000Z

    Bacteria are ubiquitous and play a critical role in many contexts. Their environment is nearly always dynamic due to the prevalence of fluid flow: creeping flow in soil, highly sheared flow in bodily conduits, and turbulent ...

  7. Dispersed flow film boiling

    E-Print Network [OSTI]

    Yoder, Graydon L.

    1980-01-01T23:59:59.000Z

    Dispersed flow consists of small liquid droplets entrained in a flowing vapor. This flow regime can occur in cryogenic equipment, in steam generators, and during nuclear reactor loss of coolant accidents. A theoretical ...

  8. EFFECT OF FILTER TEMPERATURE ON TRAPPING ZINC VAPOR

    SciTech Connect (OSTI)

    Korinko, P.

    2011-03-25T23:59:59.000Z

    To address the {sup 65}Zn contamination issue in the TEF, a multi-task experimental program was initiated. The first experimental task was completed and is reported in Ref. 1. The results of the second experimental task are reported here. This task examined the effect of filter temperature on trapping efficiency and deposit morphology. Based on the first experimental tasks that examined filter pore size and trapping efficiency, stainless steel filter media with a 20 {micro}m pore size was selected. A series of experiments using these filters was conducted during this second task to determine the effect of filter temperature on zinc vapor trapping efficiency, adhesion and morphology. The tests were conducted with the filters heated to 60, 120, and 200 C; the zinc source material was heated to 400 C for all the experiments to provide a consistent zinc source. The samples were evaluated for mass change, deposit adhesion and morphology. As expected from the physical vapor deposition literature, a difference in deposit morphology and appearance was observed between the three filter temperatures. The filter held at 60 C had the largest average mass gain while the 120 and 200 C filters exhibited similar but lower weight gains. The standard deviations were large and suggest that all three temperatures exhibited comparable gains. No zinc was detected on the backside surface of the filters indicating high efficiency for front and internal trapping. A zinc rich deposit was formed on the surface of the 60 C filter. Based on a simple tape adhesion test, the surface zinc was readily removed from the 60 C filter while less zinc deposit was removed from the 120 and 200 C filter samples. It is surmised that the higher temperatures enable the zinc to deposit within the filter media rather than on the surface. Based on the findings that all three statistically trapped the same quantity of zinc vapor and that the higher temperatures resulted in a more adherent/better trapped product, operating the filters at 120 to 200 C is recommended.

  9. Multiphase flow calculation software

    DOE Patents [OSTI]

    Fincke, James R. (Idaho Falls, ID)

    2003-04-15T23:59:59.000Z

    Multiphase flow calculation software and computer-readable media carrying computer executable instructions for calculating liquid and gas phase mass flow rates of high void fraction multiphase flows. The multiphase flow calculation software employs various given, or experimentally determined, parameters in conjunction with a plurality of pressure differentials of a multiphase flow, preferably supplied by a differential pressure flowmeter or the like, to determine liquid and gas phase mass flow rates of the high void fraction multiphase flows. Embodiments of the multiphase flow calculation software are suitable for use in a variety of applications, including real-time management and control of an object system.

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

    E-Print Network [OSTI]

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

    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.

  11. Real-time calibration of a feedback trap

    SciTech Connect (OSTI)

    Gavrilov, Mom?ilo; Jun, Yonggun; Bechhoefer, John, E-mail: johnb@sfu.ca [Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6 (Canada)

    2014-09-15T23:59:59.000Z

    Feedback traps use closed-loop control to trap or manipulate small particles and molecules in solution. They have been applied to the measurement of physical and chemical properties of particles and to explore fundamental questions in the non-equilibrium statistical mechanics of small systems. These applications have been hampered by drifts in the electric forces used to manipulate the particles. Although the drifts are small for measurements on the order of seconds, they dominate on time scales of minutes or slower. Here, we show that a recursive maximum likelihood (RML) algorithm can allow real-time measurement and control of electric and stochastic forces over time scales of hours. Simulations show that the RML algorithm recovers known parameters accurately. Experimental estimates of diffusion coefficients are also consistent with expected physical properties.

  12. Scattering of short laser pulses from trapped fermions

    E-Print Network [OSTI]

    T. Wong; Ozgur Mustecaplioglu; L. You; M. Lewenstein

    2000-03-28T23:59:59.000Z

    We investigate the scattering of intense short laser pulses off trapped cold fermionic atoms. We discuss the sensitivity of the scattered light to the quantum statistics of the atoms. The temperature dependence of the scattered light spectrum is calculated. Comparisons are made with a system of classical atoms who obey Maxwell-Boltzmann statistics. We find the total scattering increases as the fermions become cooler but eventually tails off at very low temperatures (far below the Fermi temperature). At these low temperatures the fermionic degeneracy plays an important role in the scattering as it inhibits spontaneous emission into occupied energy levels below the Fermi surface. We demonstrate temperature dependent qualitative changes in the differential and total spectrum can be utilized to probe quantum degeneracy of trapped Fermi gas when the total number of atoms are sufficiently large $(\\geq 10^6)$. At smaller number of atoms, incoherent scattering dominates and it displays weak temperature dependence.

  13. 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; Brner, 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; Baeler, 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.

  14. 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. Brner; 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. Baeler; 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.

  15. Dipole Excitation With A Paul Ion Trap Mass Spectrometer

    SciTech Connect (OSTI)

    MacAskill, J. A.; Madzunkov, S. M.; Chutjian, A. [Atomic and Molecular Physics Group, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)

    2011-06-01T23:59:59.000Z

    Preliminary results are presented for the use of an auxiliary radiofrequency (rf) excitation voltage in combination with a high purity, high voltage rf generator to perform dipole excitation within a high precision Paul ion trap. These results show the effects of the excitation frequency over a continuous frequency range on the resultant mass spectra from the Paul trap with particular emphasis on ion ejection times, ion signal intensity, and peak shapes. Ion ejection times are found to decrease continuously with variations in dipole frequency about several resonant values and show remarkable symmetries. Signal intensities vary in a complex fashion with numerous resonant features and are driven to zero at specific frequency values. Observed intensity variations depict dipole excitations that target ions of all masses as well as individual masses. Substantial increases in mass resolution are obtained with resolving powers for nitrogen increasing from 114 to 325.

  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. Jaynes-Cummings Models with trapped electrons on liquid Helium

    E-Print Network [OSTI]

    Miao Zhang; H. Y. Jia; L. F. Wei

    2009-09-01T23:59:59.000Z

    Jaynes-Cummings model is a typical model in quantum optics and has been realized with various physical systems (e.g, cavity QED, trapped ions, and circuit QED etc..) of two-level atoms interacting with quantized bosonic fields. Here, we propose a new implementation of this model by using a single classical laser beam to drive an electron floating on liquid Helium. Two lowest levels of the {\\it vertical} motion of the electron acts as a two-level "atom", and the quantized vibration of the electron along one of the {\\it parallel} directions, e.g., $x$-direction, serves the bosonic mode. These two degrees of freedom of the trapped electron can be coupled together by using a classical laser field. If the frequencies of the applied laser fields are properly set, the desirable Jaynes-Cummings models could be effectively realized.

  18. Precise determination of micromotion for trapped-ion optical clocks

    E-Print Network [OSTI]

    Keller, J; Burgermeister, T; Mehlstubler, T E

    2015-01-01T23:59:59.000Z

    As relative systematic frequency uncertainties in trapped-ion spectroscopy are approaching the low 10^{-18} range, motional frequency shifts account for a considerable fraction of the uncertainty budget. Micromotion, a driven motion fundamentally connected to the principle of the Paul trap, is a particular concern in these systems. In this article, we experimentally investigate at this level three common methods for minimizing and determining the micromotion amplitude. We develop a generalized model for a quantitative application of the photon-correlation technique, which is applicable in the commonly encountered regime where the transition linewidth is comparable to the rf drive frequency. We show that a fractional frequency uncertainty due to the 2nd-order Doppler shift below 1 x 10^{-20} can be achieved. The quantitative evaluation is verified in an interleaved measurement with the conceptually simpler resolved sideband method. If not performed deep within the Lamb-Dicke regime, a temperature-dependent off...

  19. Passive regeneration of catalyst coated knitted fiber diesel particulate traps

    SciTech Connect (OSTI)

    Mayer, A.; Emig, G.; Gmehling, B.; Popovska, N.; Hoelemann, K.; Buck, A.

    1996-09-01T23:59:59.000Z

    Knitted fiber particulate traps facilitate deep-bed structures. These have excellent filtration properties, particularly for ultra-fine particulates. They are also suitable as substrate for catalytic processes. The two characteristics are: high total surface area of the filaments, and good mass transfer. These are prerequisites for intense catalytic activity. The deposited soot is uniformly distributed. Therefore, temperature peaks are avoided during regeneration. The tested coatings lower the regeneration temperature by about 200 C to burn-off temperatures below 350 C. Further improvements seem attainable. Thus, a purely passive regeneration appears feasible for most applications. The system is autonomous and cost effective. However, in extreme low load situations, e.g. city bus services, the necessary exhaust temperatures are not attained. Hence, burners or electrical heating is necessary for trap regeneration. Nevertheless, catalytic coating is attractive for substantially reducing the regeneration energy requirements.

  20. 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.

  1. Lava Dome | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal Pwer Plant Jump to:Landowners and Wind Energy DevelopmentLaurentian Energy Authority Jump to:Dome

  2. 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.

  3. Detection of Fusion Neutrons on the Multimirror Trap GOL-3

    SciTech Connect (OSTI)

    Burdakov, A.V. [Budker Institute of Nuclear Physics (Russian Federation); England, A.C. [Korea Basic Science Institute (Korea, Republic of); Kim, C.S. [Korea Basic Science Institute (Korea, Republic of); Koidan, V.S. [Budker Institute of Nuclear Physics (Russian Federation); Kwon, M. [Korea Basic Science Institute (Korea, Republic of); Postupaev, V.V. [Budker Institute of Nuclear Physics (Russian Federation); Rovenskikh, A.F. [Budker Institute of Nuclear Physics (Russian Federation); Sulyaev, Yu.S. [Budker Institute of Nuclear Physics (Russian Federation)

    2005-01-15T23:59:59.000Z

    Recently GOL-3 has been reconfigured to a multimirror trap with improved confinement and high ion temperature. A dense plasma is created with a life time in the millisecond range. BTI neutron bubble detectors, a stilbene scintillation crystal, a BC501A liquid scintillator, and a silver-activation counter have been used for measurements of the neutron emission from GOL-3. The results are in agreement with charge-exchange (CX), spectral broadening of the D{alpha} line, and diamagnetic measurements.

  4. 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

    Pressure tow and Medium Pressure Unit Heaters Slerilirers Autoclaves Dryers FIRST CHOICE Thermo-Matic Thermostatic Float-and-Thermostatic Float-and-Thermostatic Thermo-Matic Thcrmostalic Thermo-Matic Thermostatic Thermo-Dynamic Float...-and-Thermostatic Float-and-Thermostar ic Thcrmo-Dynamic Thermo-Dynamic Bimetallic Balanced Pressure Thermostatic Balanced-Pressure Thermostatic Platen Presses I L NOTE: Unusual operating conditions, or severe corrosion may influence the choice of a steam trap...

  5. 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.

  6. Photon trap for neutralization of negative ions beams

    E-Print Network [OSTI]

    Popov, S S; Ivanov, A A; Kotelnikov, I A

    2015-01-01T23:59:59.000Z

    For effectively neutralization of the powerful negative ions beams of hydrogen and deuterium the photon target is considered in long time. The attractiveness of the traditional approach (Fabry-Perot resonators) to their creation is limited to a number of stringent technical requirements and large economic costs. In this paper we propose a new concept of non-resonant photon trap (storage) for creation more technologically simple optical neutralizers.

  7. Collective coherent population trapping in a thermal field

    E-Print Network [OSTI]

    M. Macovei; Z. Ficek; C. H. Keitel

    2006-06-01T23:59:59.000Z

    We analyzed the efficiency of coherent population trapping (CPT) in a superposition of the ground states of three-level atoms under the influence of the decoherence process induced by a broadband thermal field. We showed that in a single atom there is no perfect CPT when the atomic transitions are affected by the thermal field. The perfect CPT may occur when only one of the two atomic transitions is affected by the thermal field. In the case when both atomic transitions are affected by the thermal field, we demonstrated that regardless of the intensity of the thermal field the destructive effect on the CPT can be circumvented by the collective behavior of the atoms. An analytic expression was obtained for the populations of the upper atomic levels which can be considered as a measure of the level of thermal decoherence. The results show that the collective interaction between the atoms can significantly enhance the population trapping in that the population of the upper state decreases with increased number of atoms. The physical origin of this feature was explained by the semiclassical dressed atom model of the system. We introduced the concept of multiatom collective coherent population trapping by demonstrating the existence of collective (entangled) states whose storage capacity is larger than that of the equivalent states of independent atoms.

  8. Production trap improvements using high-efficiency internals

    SciTech Connect (OSTI)

    Delavan, D.P.; Wilson, T.T.

    1995-10-01T23:59:59.000Z

    Most of the Gas-Oil Separation Plants (GOSP) in Southern Area Producing of Saudi Aramco will be producing between 40% and 75% water cuts by the turn of the century. Many GOSPs will be producing more than twice the amount of water they were originally designed for. Consequently, modifications must be made to the GOSPs so that they will have the capacity to separate and clean up these large volumes of produced water. The most attractive option is to improve the separation efficiency of the High Pressure Production Traps (HPPT) where formation water is first removed from the wellhead fluid. These traps have historically removed very little water from the wellhead fluid. However, the following modifications have proven to significantly improve the separation efficiency of the traps: double the height of the weir, and raise the oil level from 40% to 65% full; install a new inlet device to minimize the formation of foam; install coalescing and foam-breaking internals to enhance oil/water coalescing and separation and to break the foam on top of the oil layer.

  9. Demagnetization dynamics of non-interacting trapped fermions

    E-Print Network [OSTI]

    Koller, Andrew P; Wall, Michael L; Rey, Ana Maria

    2015-01-01T23:59:59.000Z

    Motivated by several experimental efforts to understand spin diffusion and transport in ultracold fermionic gases, we study the spin dynamics of initially spin-polarized ensembles of harmonically trapped non-interacting spin-1/2 fermionic atoms, subjected to a magnetic field gradient. We obtain simple analytic expressions for spin observables in the presence of both constant and linear magnetic field gradients, with and without a spin-echo pulse, and at zero and finite temperatures. The analysis shows the relevance of spin-motional coupling in the non-interacting regime where the demagnetization decay rate at short times can be faster than the experimentally measured rates in the strongly interacting regime under similar trapping conditions. Our calculations also show that particle motion limits the ability of a spin-echo pulse to remove the effect of magnetic field inhomogeneity, and that a spin-echo pulse can instead lead to an increased decay of magnetization at times comparable to the trapping period.

  10. 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

  11. Freshwater Flow Charts - 1995

    SciTech Connect (OSTI)

    Kaiper, G V

    2003-11-21T23:59:59.000Z

    This report covers the following: (1) Explanation of Charts Showing Freshwater Flow in 1995; (2) Estimated U.S. Freshwater Flow in 1995 (chart); (3) Estimated California Freshwater Flow in 1995 (chart); (4) Estimated New Mexico Freshwater Flow in 1995 (chart); and (5) Web locations and credits.

  12. Portable wastewater flow meter

    DOE Patents [OSTI]

    Hunter, Robert M. (320 S. Wilson Ave., Bozeman, MT 59715)

    1990-01-01T23:59:59.000Z

    A portable wastewater flow meter particularly adapted for temporary use at a single location in measuring the rate of liquid flow in a circular entrance conduit of a sewer manhole both under free flow and submerged, open channel conditions and under full pipe, surcharged conditions, comprising an apparatus having a cylindrical external surface and an inner surface that constricts the flow through the apparatus in such a manner that a relationship exists between (1) the difference between the static pressure head of liquid flowing through the entrance of the apparatus and the static pressure head of liquid flowing through the constriction, and (2) the rate of liquid flow through the apparatus.

  13. Portable wastewater flow meter

    DOE Patents [OSTI]

    Hunter, Robert M. (320 S. Wilson Ave., Bozeman, MT 59715)

    1999-02-02T23:59:59.000Z

    A portable wastewater flow meter particularly adapted for temporary use at a single location in measuring the rate of liquid flow in a circular entrance conduit of a sewer manhole both under free flow and submerged, open channel conditions and under fill pipe, surcharged conditions, comprising an apparatus having a cylindrical external surface and an inner surface that constricts the flow through the apparatus in such a manner that a relationship exists between (1) the difference between the static pressure head of liquid flowing through the entrance of the apparatus and the static pressure head of liquid flowing through the constriction, and (2) the rate of liquid flow through the apparatus.

  14. Interfaces and Free Boundaries 11 (2009), 239258 Two-phase flows involving capillary barriers in heterogeneous porous media

    E-Print Network [OSTI]

    Porretta, Alessio

    2009-01-01T23:59:59.000Z

    and immiscible oil-water flow through , and thus through each i. By Darcy's law, the conservation of oil medium leads to the phenomena of oil-trapping and oil-expulsion, which is modelled with discontinuous and water phases is given for all (x, t) i ]0, T [ by the equations it ui(x, t) - o,i(ui(x, t))( po

  15. Finite volume approximation for an immiscible two-phase flow in porous media with discontinuous capillary pressure

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    by substituting the Darcy-Muskat law in the conservation equations for both phases, so that we obtain for each experiments show in particular that this scheme permits to reproduce the oil trapping phenomenon. Keywords of incompressible immiscible two-phase flows are widely used in oil engineering to predict the motion of oil

  16. Millikelvin cooling of an optically trapped microsphere in vacuum

    E-Print Network [OSTI]

    Tongcang Li; Simon Kheifets; Mark G. Raizen

    2011-01-07T23:59:59.000Z

    The apparent conflict between general relativity and quantum mechanics remains one of the unresolved mysteries of the physical world. According to recent theories, this conflict results in gravity-induced quantum state reduction of "Schr\\"odinger cats", quantum superpositions of macroscopic observables. In recent years, great progress has been made in cooling micromechanical resonators towards their quantum mechanical ground state. This work is an important step towards the creation of Schr\\"odinger cats in the laboratory, and the study of their destruction by decoherence. A direct test of the gravity-induced state reduction scenario may therefore be within reach. However, a recent analysis shows that for all systems reported to date, quantum superpositions are destroyed by environmental decoherence long before gravitational state reduction takes effect. Here we report optical trapping of glass microspheres in vacuum with high oscillation frequencies, and cooling of the center-of-mass motion from room temperature to a minimum temperature of 1.5 mK. This new system eliminates the physical contact inherent to clamped cantilevers, and can allow ground-state cooling from room temperature. After cooling, the optical trap can be switched off, allowing a microsphere to undergo free-fall in vacuum. During free-fall, light scattering and other sources of environmental decoherence are absent, so this system is ideal for studying gravitational state reduction. A cooled optically trapped object in vacuum can also be used to search for non-Newtonian gravity forces at small scales, measure the impact of a single air molecule, and even produce Schr\\"odinger cats of living organisms.

  17. 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

    # Y Strainer with 0.020" Perlorated Plate Basket 114" NPS - 600# Globe Valve 112" NPS - 600# Gate Valve 112" x 4" Nipple (Schedule 80) 1/2" x 6" Nipple (Schedule 80) 114" x 4" Nipple (Schedule 80) Orifice Plate FIGURE 3 TYPICAL DRIP LEG... down before test rig is installed. 3. "Y" Strainer ahead of steam trap may be blown down and test rig connected at strainer blow down point. FIGURE 3A 398 ESL-IE-80-04-73 Proceedings from the Second Industrial Energy Technology Conference Houston...

  18. 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.

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

    E-Print Network [OSTI]

    Jordi Mur-Petit; Juan Jos Garca-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.

  2. 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.

  3. Cryogenic surface electrode ion traps with integrated superconducting microwave resonators for polar molecular ion spectroscopy

    E-Print Network [OSTI]

    Antohi, Paul Bogdan

    2011-01-01T23:59:59.000Z

    Trapped cold molecules open the possibility of studying ultracold chemistry and astrophysical processes in laboratory settings. Their rich internal structure also makes them suitable for quantum information manipulation ...

  4. 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...

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

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

    developed and characterized. The ion trap was incorporated through the use of added terminal electrodynamic ion funnel electrodes enabling control over the axial dc gradient in...

  6. 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

  7. High-Sensitivity Two-Photon Spectroscopy in a Dark Optical Trap, based on Electron Shelving

    E-Print Network [OSTI]

    Khaykovich, B; Baluschev, S; Fathi, D; Davidson, N E

    1999-01-01T23:59:59.000Z

    We propose a new spectroscopic method for measuring weak transitions in cold and trapped atoms, which exploits the long interaction times and tight confinement offered by dark optical traps together with an electron shelving technique to achieve extremely high sensitivity. We demonstrate our scheme by measuring a 5S_{1/2}-> 5D_{5/2} two-photon transition in cold Rb atoms trapped in a new single-beam dark optical trap, using an extremely weak probe laser power of 25 micro-Watt. We were able to measure transitions with as small excitation rate as 0.09 sec^(-1).

  8. 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.

  9. 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.

  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. Ultrasonic flow metering system

    DOE Patents [OSTI]

    Gomm, Tyler J. (Meridian, ID); Kraft, Nancy C. (Idaho Falls, ID); Mauseth, Jason A. (Pocatello, ID); Phelps, Larry D. (Pocatello, ID); Taylor, Steven C. (Idaho Falls, ID)

    2002-01-01T23:59:59.000Z

    A system for determining the density, flow velocity, and mass flow of a fluid comprising at least one sing-around circuit that determines the velocity of a signal in the fluid and that is correlatable to a database for the fluid. A system for determining flow velocity uses two of the inventive circuits with directional transmitters and receivers, one of which is set at an angle to the direction of flow that is different from the others.

  12. Probing Entanglement in Adiabatic Quantum Optimization with Trapped Ions

    E-Print Network [OSTI]

    Philipp Hauke; Lars Bonnes; Markus Heyl; Wolfgang Lechner

    2015-03-19T23:59:59.000Z

    Adiabatic quantum optimization has been proposed as a route to solve NP-complete problems, with a possible quantum speedup compared to classical algorithms. However, the precise role of quantum effects, such as entanglement, in these optimization protocols is still unclear. We propose a setup of cold trapped ions that allows one to quantitatively characterize, in a controlled experiment, the interplay of entanglement, decoherence, and non-adiabaticity in adiabatic quantum optimization. We show that, in this way, a broad class of NP-complete problems becomes accessible for quantum simulations, including the knapsack problem, number partitioning, and instances of the max-cut problem. Moreover, a general theoretical study reveals correlations of the success probability with entanglement at the end of the protocol. From exact numerical simulations for small systems and linear ramps, however, we find no substantial correlations with the entanglement during the optimization. For the final state, we derive analytically a universal upper bound for the success probability as a function of entanglement, which can be measured in experiment. The proposed trapped-ion setups and the presented study of entanglement address pertinent questions of adiabatic quantum optimization, which may be of general interest across experimental platforms.

  13. Heating of trapped ultracold atoms by collapse dynamics

    E-Print Network [OSTI]

    Franck Lalo; 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$^{-1}$.}

  14. Upgrade of the electron beam ion trap in Shanghai

    SciTech Connect (OSTI)

    Lu, D.; Yang, Y.; Xiao, J.; Shen, Y.; Fu, Y.; Wei, B.; Yao, K.; Hutton, R.; Zou, Y., E-mail: zouym@fudan.edu.cn [The Key Lab of Applied Ion Beam Physics, Ministry of Education, 200433 Shanghai (China); Shanghai EBIT Lab, Institute of Modern Physics, Fudan University, 200433 Shanghai (China)

    2014-09-15T23:59:59.000Z

    Over the last few years the Shanghai electron beam ion trap (EBIT) has been successfully redesigned and rebuilt. The original machine, developed under collaboration with the Shanghai Institute of Applied Physics, first produced an electron beam in 2005. It could be tuned with electron energies between 1 and 130 keV and beam current up to 160 mA. After several years of operation, it was found that several modifications for improvements were necessary to reach the goals of better electron optics, higher photon detection, and ion injection efficiencies, and more economical running costs. The upgraded Shanghai-EBIT is made almost entirely from Ti instead of stainless steel and achieves a vacuum of less than 10{sup ?10} Torr, which helps to minimize the loss of highly changed ions through charge exchange. Meanwhile, a more compact structure and efficient cryogenic system, and excellent optical alignment have been of satisfactory. The magnetic field in the central trap region can reach up till 4.8 T with a uniformity of 2.77 10{sup ?4}. So far the upgraded Shanghai-EBIT has been operated up to an electron energy of 151 keV and a beam current of up to 218 mA, although promotion to even higher energy is still in progress. Radiation from ions as highly charged as Xe{sup 53+,} {sup 54+} has been produced and the characterization of current density is estimated from the measured electron beam width.

  15. Elbow mass flow meter

    DOE Patents [OSTI]

    McFarland, Andrew R. (College Station, TX); Rodgers, John C. (Santa Fe, NM); Ortiz, Carlos A. (Bryan, TX); Nelson, David C. (Santa Fe, NM)

    1994-01-01T23:59:59.000Z

    Elbow mass flow meter. The present invention includes a combination of an elbow pressure drop generator and a shunt-type mass flow sensor for providing an output which gives the mass flow rate of a gas that is nearly independent of the density of the gas. For air, the output is also approximately independent of humidity.

  16. Lateral flow strip assay

    DOE Patents [OSTI]

    Miles, Robin R. (Danville, CA); Benett, William J. (Livermore, CA); Coleman, Matthew A. (Oakland, CA); Pearson, Francesca S. (Livermore, CA); Nasarabadi, Shanavaz L. (Livermore, CA)

    2011-03-08T23:59:59.000Z

    A lateral flow strip assay apparatus comprising a housing; a lateral flow strip in the housing, the lateral flow strip having a receiving portion; a sample collection unit; and a reagent reservoir. Saliva and/or buccal cells are collected from an individual using the sample collection unit. The sample collection unit is immersed in the reagent reservoir. The tip of the lateral flow strip is immersed in the reservoir and the reagent/sample mixture wicks up into the lateral flow strip to perform the assay.

  17. Gravid Mosquito Trap P462 -Trap The ChemTica GMT operates on 4 size D cell batteries. A photo-activated switch turns on the fan

    E-Print Network [OSTI]

    Ishida, Yuko

    batteries. A photo-activated switch turns on the fan at dusk. Manual shutoff is required at dawn to prevent at dawn to prevent loss of trapped mosquitoes. Power is supplied by four D cell batteries. The upper case

  18. 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. Teigelhfer

    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.

  19. ACOUSTIC WAVE TRAPPING IN ONE-DIMENSIONAL AXISYMMETRIC ARRAYS

    E-Print Network [OSTI]

    . Introduction Acoustic resonances are readily observed in axial flow compressors and this has led to many that both the acoustic and the water-wave channel problems reduced to the determination of the eigenvalues

  20. 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

  1. 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

  2. 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

  3. Thermodynamic limits of nanophotonic light trapping in thin film silicon solar cells1

    E-Print Network [OSTI]

    Schiff, Eric A.

    with solar tracking may realize the predicted JSC improvement. PACS Nos.: 88.40.jj, 42.79.Dj, 88.05.De to a significant improvement in light-trapping for cells used with solar trackingARTICLE Thermodynamic limits of nanophotonic light trapping in thin film silicon solar cells1 Brian

  4. Euler buckling-induced folding and rotation of red blood cells in an optical trap

    E-Print Network [OSTI]

    Sharma, Shobhona

    Euler buckling-induced folding and rotation of red blood cells in an optical trap A Ghosha 005, India Abstract. We investigate the physics of an optically-driven micromotor of biological origin. When a single, live red blood cell is placed in an optical trap, the normal biconcave disk shape

  5. Passive torque wrench and angular position detection using a single-beam optical trap

    E-Print Network [OSTI]

    Wang, Michelle

    Passive torque wrench and angular position detection using a single-beam optical trap James Inman,1 August 26, 2010 The recent advent of angular optical trapping techniques has allowed for rotational torsional measurements across a wide range of biological systems. 2010 Optical Society of America OCIS

  6. Torque-generating malaria-infected red blood cells in an optical trap

    E-Print Network [OSTI]

    Sharma, Shobhona

    Torque-generating malaria-infected red blood cells in an optical trap J.A. Dharmadhikari, S. Roy, A 005, India # atmol1@tifr.res.in Abstract: We have used optical tweezers to trap normal and Plasmodium emerge from our experiments. Firstly, while the optical field modifies both types of RBCs in the same

  7. Heating of trapped ions from the quantum ground state Q. A. Turchette,*,

    E-Print Network [OSTI]

    Sackett, Cass

    Heating of trapped ions from the quantum ground state Q. A. Turchette,*, D. Kielpinski, B. E. King. Monroe, and D. J. Wineland Time and Frequency Division, National Institute of Standards and Technology heating of laser-cooled 9 Be ions held in radio-frequency Paul traps. We have measured heating rates

  8. I. Top 20 TA Traps 83 II. Team Meeting Guidelines 85

    E-Print Network [OSTI]

    Minnesota, University of

    Other Teaching Resources Page I. Top 20 TA Traps 83 II. Team Meeting Guidelines 85 III. TA Office I. Top 20 TA Traps This list has been compiled by mentor TAs to help you avoid some common pitfalls of being a TA. These are the top twenty things TAs do that interfere with the work of teaching. General

  9. I. Top 20 TA Traps 129 II. Team Meeting Guidelines 131

    E-Print Network [OSTI]

    Minnesota, University of

    Chapter 5 Other Teaching Resources Page I. Top 20 TA Traps 129 II. Team Meeting Guidelines 131 III for TAs 152 #12;#12;Page 129 I. Top 20 TA Traps This list has been compiled by mentor TAs to help you avoid some common pitfalls of being a TA. These are the top twenty things TAs do that interfere

  10. I. Top 20 TA Traps 129 II. Team Meeting Guidelines 131

    E-Print Network [OSTI]

    Minnesota, University of

    Chapter 5 Other Teaching Resources Page I. Top 20 TA Traps 129 II. Team Meeting Guidelines 131 III for TAs 152 #12;#12;I. Top 20 TA Traps This list has been compiled by mentor TAs to help you avoid some common pitfalls of being a TA. These are the top twenty things TAs do that interfere with the work

  11. Repulsive trap for two electrons in a magnetic field A. D. Chepelianskii1

    E-Print Network [OSTI]

    Shepelyansky, Dima

    of crossed electric and magnetic fields. It is found that near one antidot the electron pair can be trapped for a long time, and the escape rate from such a trap is proportional to the square of a weak electric field field. Experiments with antidot lattices were car- ried out by different experimental groups see, e

  12. 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...

  13. Efficiency of Surveying, Baiting, and Trapping Wild Pigs at Fort Benning, Georgia Brian Lee Williams

    E-Print Network [OSTI]

    Ditchkoff, Steve

    Efficiency of Surveying, Baiting, and Trapping Wild Pigs at Fort Benning, Georgia by Brian Lee surveys, trapping efficiency, Fort Benning Copyright 2010 by Brian Lee Williams Approved by Stephen S This study, conducted at Fort Benning, Georgia, sought to develop more efficient ways of surveying

  14. 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

  15. The responses of freshwater macroinvertebrates to different wavelengths in submerged aquatic light traps

    E-Print Network [OSTI]

    Moeller, Edward F.

    1996-01-01T23:59:59.000Z

    attracted to green light emitting diodes more than infrared, amber, orange, red, white, or unlit diodes. The vertical placement of the trap in the water column is also important. Beehler and Webb (1992) found that traps placed at the bottom of the water...

  16. 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

  17. 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

  18. 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 observe an enhancement in solar absorption of almost 40% relative to a planar cell. Improvements

  19. 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...

  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

    An investigation of the sympathetic cooling method for the studies of large ultra-cold molecular ions in a quadrupole ion trap has been conducted.Molecular dynamics simulations are performed to study the rf heating mechanisms in the ion trap...

  1. 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

  2. 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

  3. Enhanced trapping of colding lithium by using the multiple-sideband cooling in a two-dimensional magneto-optical trap

    E-Print Network [OSTI]

    Li, Kai; Gao, Tianyou; Peng, Shi-Guo; Jiang, Kaijun

    2015-01-01T23:59:59.000Z

    Trapping lithium with a big number in a simplified experimental setup has difficulties and challenges today. In this paper, we experimentally demonstrate the enhancement of \\textsuperscript{6}Li trapping efficiency in a three-dimensional magneto-optical trap (3D MOT) by using the multiple-sideband cooling in a two-dimensional magneto-optical trap (2D MOT). To improve the number of trapped atoms, we broaden the cooling light spectrum to 102 MHz composed of seven frequency components and then trap atoms with a number of $6.0\\times10^8$ which is about 4 times compared to that in the single-frequency cooling. The capture velocity and dependence of atomic number on the laser detuning have been analyzed, where the experimental result has a good agreement with the theoretical prediction based on a simple two-level model. We also analyze the loss rate of alkali metals due to fine-structure exchanging collisions and find that the multiple-sideband cooling is special valid for lithium.

  4. 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.

  5. 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.

  6. 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 Zrich, Vladimir-Prelog-Weg 2, CH-8093 Zrich (Switzerland); Isenor, Merrill; Signorell, Ruth [Laboratory of Physical Chemistry, ETH Zrich, Vladimir-Prelog-Weg 2, CH-8093 Zrich (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.

  7. 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.

  8. Sudden Expansion of a One-Dimensional Bose Gas from Power-Law Traps

    E-Print Network [OSTI]

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

    2015-03-27T23:59:59.000Z

    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 Lieb-Liniger equations in the thermodynamic limit. For expansion from a harmonic trap, and in the limits of very weak and very strong interactions, we recover the self-similar scaling solutions known from the hydrodynamic approach. For all other power-law traps and arbitrary interaction strengths, the expansion is not self-similar and shows strong dependence of the density profile evolution on the trap anharmonicity. We also characterize dynamical fermionization of the expanding cloud in terms of correlation functions describing phase and density fluctuations.

  9. Ion-neutral sympathetic cooling in a hybrid linear rf Paul and magneto-optical trap

    E-Print Network [OSTI]

    Goodman, D S; Wells, J E; Narducci, F A; Smith, W W

    2012-01-01T23:59:59.000Z

    Long range polarization forces between ions and neutral atoms result in large elastic scattering cross sections, e.g., 10^6 a.u. for Na+ on Na or Ca+ on Na at cold and ultracold temperatures. This suggests that a hybrid ion-neutral trap should offer a general means for significant sympathetic cooling of atomic or molecular ions. We present SIMION 7.0 simulation results concerning the advantages and limitations of sympathetic cooling within a hybrid trap apparatus, consisting of a linear rf Paul trap concentric with a Na magneto-optical trap (MOT). This paper explores the impact of various heating mechanisms on the hybrid system and how parameters related to the MOT, Paul trap, number of ions, and ion species affect the efficiency of the sympathetic cooling.

  10. Ion-neutral sympathetic cooling in a hybrid linear rf Paul and magneto-optical trap

    E-Print Network [OSTI]

    D. S. Goodman; I. Sivarajah; J. E. Wells; F. A. Narducci; W. W. Smith

    2012-08-31T23:59:59.000Z

    Long range polarization forces between ions and neutral atoms result in large elastic scattering cross sections, e.g., 10^6 a.u. for Na+ on Na or Ca+ on Na at cold and ultracold temperatures. This suggests that a hybrid ion-neutral trap should offer a general means for significant sympathetic cooling of atomic or molecular ions. We present SIMION 7.0 simulation results concerning the advantages and limitations of sympathetic cooling within a hybrid trap apparatus, consisting of a linear rf Paul trap concentric with a Na magneto-optical trap (MOT). This paper explores the impact of various heating mechanisms on the hybrid system and how parameters related to the MOT, Paul trap, number of ions, and ion species affect the efficiency of the sympathetic cooling.

  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. Laser cooling of a trapped particle with increased Rabi frequencies

    SciTech Connect (OSTI)

    Blake, Tony; Kurcz, Andreas; Saleem, Norah S.; Beige, Almut [School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT (United Kingdom)

    2011-11-15T23:59:59.000Z

    This paper analyzes 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}<<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 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.

  13. 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.

  14. Magnetic-field dependent trap loss of ultracold metastable helium

    E-Print Network [OSTI]

    J. S. Borbely; R. van Rooij; S. Knoop; W. Vassen

    2011-11-24T23:59:59.000Z

    We have experimentally studied the magnetic-field dependence of the decay of a Bose-Einstein condensate of metastable 4He atoms confined in an optical dipole trap, for atoms in the m=+1 and m=-1 magnetic substates, and up to 450 G. Our measurements confirm long-standing calculations of the two-body loss rate coefficient that show an increase above 50 G. We demonstrate that for m=-1 atoms, decay is due to three-body recombination only, with a three-body loss rate coefficient of 6.5(0.4)(0.6)10^(-27)cm^6s^(-1), which is interesting in the context of universal few-body theory. We have also searched for a recently-predicted d-wave Feshbach resonance, but did not observe it.

  15. Graphene plasmonics for light trapping and absorption engineering

    E-Print Network [OSTI]

    Zhang, Jianfa; Liu, Wei; Yuan, Xiaodong; Qin, Shiqiao

    2015-01-01T23:59:59.000Z

    Plasmonics can be used to improve absorption in optoelectronic devices and has been intensively studied for solar cells and photodetectors. Graphene has recently emerged as a powerful plasmonic material. It shows significantly less losses compared to traditional plasmonic materials such as gold and silver and its plasmons can be tuned by changing the Fermi energy with chemical or electrical doping. Here we propose the usage of graphene plasmonics for light trapping in optoelectronic devices and show that the excitation of localized plasmons in doped, nanostructured graphene can enhance optical absorption in its surrounding media including both bulky and two-dimensional materials by tens of times, which may lead to a new generation of highly efficient, spectrally selective photodetectors in mid-infrared and THz ranges. The proposed concept could even revolutionize the field of plasmonic solar cells if graphene plasmons in the visible and near-infrared are realized.

  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. Local Detection of Quantum Correlations with a Single Trapped Ion

    E-Print Network [OSTI]

    M. Gessner; M. Ramm; T. Pruttivarasin; A. Buchleitner; H. -P. Breuer; H. Haeffner

    2014-08-11T23:59:59.000Z

    As one of the most striking features of quantum mechanics, quantum correlations are at the heart of quantum information science. Detection of correlations usually requires access to all the correlated subsystems. However, in many realistic scenarios this is not feasible since only some of the subsystems can be controlled and measured. Such cases can be treated as open quantum systems interacting with an inaccessible environment. Initial system-environment correlations play a fundamental role for the dynamics of open quantum systems. Following a recent proposal, we exploit the impact of the correlations on the open-system dynamics to detect system-environment quantum correlations without accessing the environment. We use two degrees of freedom of a trapped ion to model an open system and its environment. The present method does not require any assumptions about the environment, the interaction or the initial state and therefore provides a versatile tool for the study of quantum systems.

  18. Theory of phonon dynamics in an ion trap

    E-Print Network [OSTI]

    Dutta, T; Sengupta, K

    2015-01-01T23:59:59.000Z

    We develop a theory to address the non-equilibrium dynamics of phonons in a one-dimensional trapped ion system. We elaborate our earlier results obtained in Phys. Rev. Lett. {\\bf 111}, 170406 (2013) to chart out the mechanism of dynamics-induced cooling and entanglement generation between phonons in these systems when subjected to a linear ramp protocol inducing site-specific tuning of on-site interactions between the phonons. We further extend these studies to non-linear ramps and periodic drive protocols and identify the optimal ramp protocol for minimal cooling and entanglement generation time. We qualitatively address the effect of noise arising out of fluctuation of the intensity of the laser used to generate entanglement and provide a detailed discussion of a realistic experimental setup which may serve as a test bed for our theory.

  19. 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.

  20. Entropic Trapping of Particles at Polymer Surfaces and Interfaces

    E-Print Network [OSTI]

    Galen T. Pickett

    2015-05-22T23:59:59.000Z

    I consider the possibility that Gaussian random walk statistics are sufficient to trap nanoscopic additives at either a polymer interface or surface. When an additive particle goes to the free surface, two portions of the polymer surface energy behave quite differently. The purely enthalpic contribution increases the overall free energy when the additive protrudes above the level of the polymer matrix. The entropic part of the surface energy arising from constraints that segments near a surface can't cross it, is partly relaxed when the additive moves to the free surface. These two portions of the polymer surface energy determine the equilibrium wetting angle formed between the additive and the polymer matrix, the measurement of which in an experiment would allow an independent determination of each piece of the polymer surface energy.

  1. 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.

  2. Shelving and Probe Efficiency in Trapped Ion Experiments

    E-Print Network [OSTI]

    Schacht, M

    2014-01-01T23:59:59.000Z

    A generalized probe sequence typical of trapped ion experiments using shelving is studied. Detection efficiency is analyzed for finite shelved state lifetimes and using multi-modal count distributions. Multi-modal distributions are more appropriate for measurements that use a small number of ions than the simple Poisson counting statistics usually considered and have a larger variance that may be significant in determining uncertainties and in making weighted fits. Optimal probe times and the resulting state detection efficiency and sensitivity are determined for arbitrary cooling rates, initial states and shelved state lifetimes, in terms of a probe coherence time {\\tau}p. A universal optimal probe time of tp ~ 0.43{\\tau}p is shown to give an almost optimal probe sensitivity for most systems.

  3. Dust trapping by spiral arms in gravitationally unstable protostellar discs

    E-Print Network [OSTI]

    Dipierro, Giovanni; Lodato, Giuseppe; Testi, Leonardo

    2015-01-01T23:59:59.000Z

    In this paper we discuss the influence of gravitational instabilities in massive protostellar discs on the dynamics of dust grains. Starting from a Smoothed Particle Hydrodynamics (SPH) simulation, we have computed the evolution of the dust in a quasi-static gas density structure typical of self-gravitating disc. For different grain size distributions we have investigated the capability of spiral arms to trap particles. We have run 3D radiative transfer simulations in order to construct maps of the expected emission at (sub-)millimetre and near-infrared wavelengths. Finally, we have simulated realistic observations of our disc models at (sub-)millimetre and near-infrared wavelengths as they may appear with the Atacama Large Millimetre/sub-millimetre Array (ALMA) and the High-Contrast Coronographic Imager for Adaptive Optics (HiCIAO) in order to investigate whether there are observational signatures of the spiral structure. We find that the pressure inhomogeites induced by gravitational instabilities produce a...

  4. 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.

  5. From invasion percolation to flow in rock fracture networks

    E-Print Network [OSTI]

    Wettstein, Salomon J; Araujo, Nuno A M; Lanyon, Bill; Herrmann, Hans J

    2011-01-01T23:59:59.000Z

    The main purpose of this work is to simulate two-phase flow in the form of immiscible displacement through anisotropic, three-dimensional (3D) discrete fracture networks (DFN). The considered DFNs are artificially generated, based on a general distribution function or are conditioned on measured data from deep geological investigations. We introduce several modifications to the invasion percolation (MIP) to incorporate fracture inclinations, intersection lines, as well as the hydraulic path length inside the fractures. Additionally a trapping algorithm is implemented that forbids any advance of the invading fluid into a region, where the defending fluid is completely encircled by the invader and has no escape route. We study invasion, saturation, and flow through artificial fracture networks, with varying anisotropy and size and finally compare our findings to well studied, conditioned fracture networks.

  6. Modification of the Carbon and Beryllium Walls in JET by Erosion, Redeposition and Deuterium Trapping after the 1991 Discharge Period

    E-Print Network [OSTI]

    Modification of the Carbon and Beryllium Walls in JET by Erosion, Redeposition and Deuterium Trapping after the 1991 Discharge Period

  7. Experimental investigations on sodium plugging in narrow flow channels.

    SciTech Connect (OSTI)

    Momozaki, Y.; Cho, D. H.; Sienicki, J. J.; Moisseytsev, A.; Nuclear Engineering Division

    2010-08-01T23:59:59.000Z

    A series of experiments was performed to investigate the potential for plugging of narrow flow channels of sodium by impurities (e.g., oxides). In the first phase of the experiments, clean sodium was circulated through the test sections simulating flow channels in a compact diffusion-bonded heat exchanger such as a printed circuit heat exchanger. The primary objective was to see if small channels whose cross sections are semicircles of 2, 4, and 6 mm in diameter are usable in liquid sodium applications where sodium purity is carefully controlled. It was concluded that the 2-mm channels, the smallest of the three, could be used in clean sodium systems at temperatures even as low as 100 to 110 C without plugging. In the second phase, sodium oxide was added to the loop, and the oxygen concentration in the liquid sodium was controlled by means of varying the cold-trap temperature. Intentional plugging was induced by creating a cold spot in the test sections, and the subsequent plugging behavior was observed. It was found that plugging in the 2-mm test section was initiated by lowering the cold spot temperature below the cold-trap temperature by 10 to 30 C. Unplugging of the plugged channels was accomplished by heating the affected test section.

  8. Turbulent flow in graphene

    E-Print Network [OSTI]

    Kumar S. Gupta; Siddhartha Sen

    2010-06-05T23:59:59.000Z

    We demonstrate the possibility of a turbulent flow of electrons in graphene in the hydrodynamic region, by calculating the corresponding turbulent probability density function. This is used to calculate the contribution of the turbulent flow to the conductivity within a quantum Boltzmann approach. The dependence of the conductivity on the system parameters arising from the turbulent flow is very different from that due to scattering.

  9. Optimized holographic optical traps Marco Polin, Kosta Ladavac, # SangHyuk Lee, Yael Roichman, and David G. Grier

    E-Print Network [OSTI]

    Grier, David

    Optimized holographic optical traps Marco Polin, Kosta Ladavac, # SangHyuk Lee, Yael Roichman 10003 (Dated: July 18, 2005) Holographic optical traps use the forces exerted by computer methods for optimizing holographic optical traps' e#ciency and accuracy, and an optimal statistical

  10. Optimized holographic optical traps Marco Polin, Kosta Ladavac, # SangHyuk Lee, Yael Roichman, and David G. Grier

    E-Print Network [OSTI]

    Grier, David

    Optimized holographic optical traps Marco Polin, Kosta Ladavac, # SangHyuk Lee, Yael Roichman 10003 (Dated: December 26, 2011) Holographic optical traps use the forces exerted by computer methods for optimizing holographic optical traps' e#ciency and accuracy, and an optimal statistical

  11. Performance of optical traps with geometric aberrations Yael Roichman, Alex Waldron, Emily Gardel, and David G. Grier

    E-Print Network [OSTI]

    Grier, David

    Performance of optical traps with geometric aberrations Yael Roichman, Alex Waldron, Emily Gardel, NY 10003 (Dated: December 25, 2011) We assess the influence of geometric aberrations on optical traps holographic optical tweezers. The traps' lateral stiffness turns out to be insensitive to moderate amounts

  12. Performance of optical traps with geometric aberrations Yael Roichman, Alex Waldron, Emily Gardel, and David G. Grier

    E-Print Network [OSTI]

    Grier, David

    Performance of optical traps with geometric aberrations Yael Roichman, Alex Waldron, Emily Gardel, NY 10003 (Dated: November 12, 2005) We assess the influence of geometric aberrations on optical traps holographic optical tweezers. The traps' lateral stiffness turns out to be insensitive to moderate amounts

  13. Insensitivity of the rate of ion motional heating to trap-electrode material over a large temperature range

    E-Print Network [OSTI]

    Chiaverini, John

    We present measurements of trapped-ion motional-state heating rates in niobium and gold surface-electrode ion traps over a range of trap-electrode temperatures from approximately 4 K to room temperature (295 K) in a single ...

  14. Trapped proton fluxes at low Earth orbits measured by the PAMELA experiment

    E-Print Network [OSTI]

    Adriani, O; Bazilevskaya, G A; Bellotti, R; Boezio, M; Bogomolov, E A; Bongi, M; Bonvicini, V; Bottai, S; Bruno, A; Cafagna, F; Campana, D; Carbone, R; Carlson, P; Casolino, M; Castellini, G; Danilchenko, I A; De Donato, C; De Santis, C; De Simone, N; Di Felice, V; Formato, V; Galper, A M; Karelin, A V; Koldashov, S V; Koldobskiy, S; Krutkov, S Y; Kvashnin, A N; Leonov, A; Malakhov, V; Marcelli, L; Martucci, M; Mayorov, A G; Menn, W; Merg, M; Mikhailov, V V; Mocchiutti, E; Monaco, A; Mori, N; Munini, R; Osteria, G; Palma, F; Panico, B; Papini, P; Pearce, M; Picozza, P; Ricci, M; Ricciarini, S B; Sarkar, R; Scotti, V; Simon, M; Sparvoli, R; Spillantini, P; Stozhkov, Y I; Vacchi, A; Vannuccini, E; Vasilyev, G I; Voronov, S A; Yurkin, Y T; Zampa, G; Zampa, N; Zverev, V G

    2014-01-01T23:59:59.000Z

    We report an accurate measurement of the geomagnetically trapped proton fluxes for kinetic energy above > 70 MeV performed by the PAMELA mission at low Earth orbits (350-610 km). Data were analyzed in the frame of the adiabatic theory of charged particle motion in the geomagnetic field. Flux properties were investigated in detail, providing a full characterization of the particle radiation in the South Atlantic Anomaly region, including locations, energy spectra and pitch angle distributions. PAMELA results significantly improve the description of the Earth's radiation environment at low altitudes placing important constraints on the trapping and interaction processes, and can be used to validate current trapped particle radiation models.

  15. 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.

  16. 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 0.420?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.

  17. 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.

  18. 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.

  19. 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, Universitt Erlangen-Nrnberg, 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.

  20. Trapping processes in CaS:Eu{sup 2+},Tm{sup 3+}

    SciTech Connect (OSTI)

    Jia, Dongdong [Department of Materials Science and Engineering, Tsinghua University, Beijing, (China)] [Department of Materials Science and Engineering, Tsinghua University, Beijing, (China); Jia, Weiyi [Department of Physics, University of Puerto Rico, Mayaguez, Puerto Rico 00681 (Puerto Rico)] [Department of Physics, University of Puerto Rico, Mayaguez, Puerto Rico 00681 (Puerto Rico); Evans, D. R. [Department of Physics and Astronomy, University of Georgia, Athens, Georgia 30602 (United States)] [Department of Physics and Astronomy, University of Georgia, Athens, Georgia 30602 (United States); Dennis, W. M. [Department of Physics and Astronomy, University of Georgia, Athens, Georgia 30602 (United States)] [Department of Physics and Astronomy, University of Georgia, Athens, Georgia 30602 (United States); Liu, Huimin [Department of Physics, University of Puerto Rico, Mayaguez, Puerto Rico 00681 (Puerto Rico)] [Department of Physics, University of Puerto Rico, Mayaguez, Puerto Rico 00681 (Puerto Rico); Zhu, Jing [Department of Materials Science and Engineering, Tsinghua University, Beijing, (China)] [Department of Materials Science and Engineering, Tsinghua University, Beijing, (China); Yen, W. M. [Department of Physics and Astronomy, University of Georgia, Athens, Georgia 30602 (United States)] [Department of Physics and Astronomy, University of Georgia, Athens, Georgia 30602 (United States)

    2000-09-15T23:59:59.000Z

    CaS:Eu{sup 2+},Tm{sup 3+} is a persistent red phosphor. Thermoluminescence was measured under different excitation and thermal treatment conditions. The results reveal that the charge defects, created by substituting Tm{sup 3+} for Ca{sup 2+}, serve as hole traps for the afterglow at room temperature. Tm{sup 3+} plays the role of deep electron trapping centers, capturing electrons either through the conduction band or directly from the excited Eu{sup 2+} ions. These two processes, in which two different sites of Tm{sup 3+} are involved, correspond to two traps with different depths. (c) 2000 American Institute of Physics.

  1. Wavelength-Scale Imaging of Trapped Ions using a Phase Fresnel lens

    E-Print Network [OSTI]

    A. Jechow; E. W. Streed; B. G. Norton; M. J. Petrasiunas; D. Kielpinski

    2011-01-24T23:59:59.000Z

    A microfabricated phase Fresnel lens was used to image ytterbium ions trapped in a radio frequency Paul trap. The ions were laser cooled close to the Doppler limit on the 369.5 nm transition, reducing the ion motion so that each ion formed a near point source. By detecting the ion fluorescence on the same transition, near diffraction limited imaging with spot sizes of below 440 nm (FWHM) was achieved. This is the first demonstration of imaging trapped ions with a resolution on the order of the transition wavelength.

  2. 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.

  3. Microelectromechanical flow control apparatus

    DOE Patents [OSTI]

    Okandan, Murat (NE Albuquerque, NM)

    2009-06-02T23:59:59.000Z

    A microelectromechanical (MEM) flow control apparatus is disclosed which includes a fluid channel formed on a substrate from a first layer of a nonconducting material (e.g. silicon nitride). A first electrode is provided on the first layer of the nonconducting material outside the flow channel; and a second electrode is located on a second layer of the nonconducting material above the first layer. A voltage applied between the first and second electrodes deforms the fluid channel to increase its cross-sectional size and thereby increase a flow of a fluid through the channel. In certain embodiments of the present invention, the fluid flow can be decreased or stopped by applying a voltage between the first electrode and the substrate. A peristaltic pumping of the fluid through the channel is also possible when the voltage is applied in turn between a plurality of first electrodes and the substrate. A MEM flow control assembly can also be formed by providing one or more MEM flow control devices on a common substrate together with a submicron filter. The MEM flow control assembly can optionally include a plurality of pressure sensors for monitoring fluid pressure and determining flow rates through the assembly.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. Laser cooling and trapping of potassium at magic wavelengths

    E-Print Network [OSTI]

    M. S. Safronova; U. I. Safronova; Charles W. Clark

    2013-01-14T23:59:59.000Z

    We carry out a systematic study of the static and dynamic polarizabilities of the potassium atom using a first-principles high-precision relativistic all-order method in which all single, double, and partial triple excitations of the Dirac-Fock wave functions are included to all orders of perturbation theory. Recommended values are provided for a large number of electric-dipole matrix elements. Static polarizabilities of the 4s, 4p_j, 5s, 5p_j, and 3d_j states are compared with other theory and experiment where available. We use the results of the polarizability calculations to identify magic wavelengths for the 4s-np transitions for $n = 4, 5$, i.e. those wavelengths for which the two levels have the same ac Stark shifts. These facilitate state-insensitive optical cooling and trapping. The magic wavelengths for the $4s-5p$ transitions are of particular interest for attaining a quantum gas of potassium at high phase-space density. We find 20 such wavelengths in the technically interest region of 1050-1130 nm. Uncertainties of all recommended values are estimated.

  9. Capped colloids as light-mills in optical traps

    E-Print Network [OSTI]

    F. S. Merkt; A. Erbe; P. Leiderer

    2006-05-18T23:59:59.000Z

    Custom-designed colloidal particles in an optical tweezers act as light-mills in a fluid. In particular, aqueous suspensions of capped colloids, in which half of the surface is covered with metal layers, are investigated. Due to their asymmetry, the capped colloids can act as rotators when exposed to intense laser fields. Particles of 4.7 micrometer in diameter are observed rotating around the focus of a laser beam. For low intensities, particles become trapped close to the spot of highest laser intensity. Above a threshold value of about 4 mW in total beam intensity, the particles move away from the center of the focus and start to rotate at frequencies of about 1 Hz. The balance of forces due to light pressure and hydrodynamic forces gives a constant rotation rate. The speed of the spinning particle increases linearly with laser power to above 2 Hz until the particles are ejected from the focus for intensities higher than 7 mW. Magnetic caps introduce further possibilities to tune the rotation rates.

  10. 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.

  11. 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.

  12. Trapped surfaces and nature of singularities in Lyra's geometry

    E-Print Network [OSTI]

    Amir Hadi Ziaie; Arash Ranjbar; Hamid Reza Sepangi

    2015-01-10T23:59:59.000Z

    Motivated by the geometrical interpretation of Brans-Dicke (BD) scalar field which may also act as a torsion potential in Lyra geometry, we study the effects of spacetime torsion on the dynamics of a collapsing massive star. Taking the interior spacetime as the FLRW metric and the matter content as spherically symmetric, homogeneous perfect fluid with the equation of state (EoS) $p=w\\rho$, we show that the collapse ends in a spacetime singularity which is of the strong curvature type in the sense of Tipler. Whether the trapped surfaces form during the dynamical evolution of the collapse depends on the torsion parameter, related to the BD coupling parameter, and the EoS subject to the conditions on physical reasonableness of the collapse configuration. Hence, the space of torsion and EoS parameters is divided into two portions, one for which the collapse process leads to the formation of apparent horizon and the other for which the apparent horizon is failed to form in the interior region. The nature of the singularity is examined from the exterior perspective, by searching for the existence of radial null geodesics reaching the faraway observers. Moreover, it is found that the effects of a dynamical torsion can be transferred to the outside region of the collapsing star, making the exterior region dynamic.

  13. Trapped Ion Quantum Error Correcting Protocols Using Only Global Operations

    E-Print Network [OSTI]

    Joseph F. Goodwin; Benjamin J. Brown; Graham Stutter; Howard Dale; Richard C. Thompson; Terry Rudolph

    2014-07-07T23:59:59.000Z

    Quantum error-correcting codes are many-body entangled states that are prepared and measured using complex sequences of entangling operations. Each element of such an entangling sequence introduces noise to delicate quantum information during the encoding or reading out of the code. It is important therefore to find efficient entangling protocols to avoid the loss of information. Here we propose an experiment that uses only global entangling operations to encode an arbitrary logical qubit to either the five-qubit repetition code or the five-qubit code, with a six-ion Coulomb crystal architecture in a Penning trap. We show that the use of global operations enables us to prepare and read out these codes using only six and ten global entangling pulses, respectively. The proposed experiment also allows the acquisition of syndrome information during readout. We provide a noise analysis for the presented protocols, estimating that we can achieve a six-fold improvement in coherence time with noise as high as $\\sim 1\\%$ on each entangling operation.

  14. 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.

  15. High-field penning-malmberg trap: confinement properties and use in positron accumulation

    SciTech Connect (OSTI)

    Hartley, J.H.

    1997-09-01T23:59:59.000Z

    This dissertation reports on the development of the 60 kG cryogenic positron trap at Lawrence Livermore National Laboratory, and compares the trap`s confinement properties with other nonneutral plasma devices. The device is designed for the accumulation of up to 2{times}10{sup 9} positrons from a linear-accelerator source. This positron plasma could then be used in Bhabha scattering experiments. Initial efforts at time-of-flight accumulation of positrons from the accelerator show rapid ({approximately}100 ms) deconfinement, inconsistent with the long electron lifetimes. Several possible deconfinement mechanisms have been explored, including annihilation on residual gas, injection heating, rf noise from the accelerator, magnet field curvature, and stray fields. Detailed studies of electron confinement demonstrate that the empirical scaling law used to design the trap cannot be extrapolated into the parameter regime of this device. Several possible methods for overcoming these limitations are presented.

  16. An optical-fiber interface to a trapped-ion quantum computer

    E-Print Network [OSTI]

    Kim, Tony Hyun

    2011-01-01T23:59:59.000Z

    The trapped-ion quantum computer is an atom-based implementation of a quantum computer that has successfully demonstrated numerous quantum algorithms and the potential for scalability. Fundamental to its operation is the ...

  17. 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

  18. Additional Steam Traps Increase Production of a Drum Oven at a Petroleum Jelly Plant

    SciTech Connect (OSTI)

    Not Available

    2002-03-01T23:59:59.000Z

    Additional steam traps were installed on the drum oven at a petroleum jelly production facility at an ExxonMobil plant in Nigeria. The installation improved heat transfer and saved energy.

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

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

    and CHF Peden.2008."Excellent Sulfur Resistance of PtBaOCeO2 Lean NOx Trap Catalysts."Applied Catalysis. B, Environmental 84(3-4):545-551. doi:10.1016j.apcatb.2008.05.009...

  20. 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.

  1. Decoherence and Quantum Interference assisted electron trapping in a quantum dot

    E-Print Network [OSTI]

    Ahmed El Halawany; Michael N. Leuenberger

    2013-08-08T23:59:59.000Z

    We present a theoretical model for the dynamics of an electron that gets trapped by means of decoherence and quantum interference in the central quantum dot (QD) of a semiconductor nanoring (NR) made of five QDs, between 100 K and 300 K. The electron's dynamics is described by a master equation with a Hamiltonian based on the tight-binding model, taking into account electron-LO phonon interaction (ELOPI). Based on this configuration, the probability to trap an electron with no decoherence is almost 27%. In contrast, the probability to trap an electron with decoherence is 70% at 100 K, 63% at 200 K and 58% at 300 K. Our model provides a novel method of trapping an electron at room temperature.

  2. On the application of radio frequency voltages to ion traps via helical resonators

    E-Print Network [OSTI]

    J. D. Siverns; L. R. Simkins; S. Weidt; W. K. Hensinger

    2011-10-18T23:59:59.000Z

    Ions confined using a Paul trap require a stable, high voltage and low noise radio frequency (RF) potential. We present a guide for the design and construction of a helical coil resonator for a desired frequency that maximises the quality factor for a set of experimental constraints. We provide an in-depth analysis of the system formed from a shielded helical coil and an ion trap by treating the system as a lumped element model. This allows us to predict the resonant frequency and quality factor in terms of the physical parameters of the resonator and the properties of the ion trap. We also compare theoretical predictions with experimental data for different resonators, and predict the voltage applied to the ion trap as a function of the Q-factor, input power and the properties of the resonant circuit.

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

    E-Print Network [OSTI]

    Goerg, Georg M; Hbert-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. 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.

  5. 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 ...

  6. Efficient Light Trapping in Inverted Nanopyramid Thin Crystalline Silicon Membranes for Solar Cell Applications

    E-Print Network [OSTI]

    Mavrokefalos, Anastassios

    Thin-film crystalline silicon (c-Si) solar cells with light-trapping structures can enhance light absorption within the semiconductor absorber layer and reduce material usage. Here we demonstrate that an inverted nanopyramid ...

  7. 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 ...

  8. 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 ...

  9. 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 ...

  10. Polaronic trapping of electrons and holes by native defects in anatase TiO{sub 2}

    SciTech Connect (OSTI)

    Morgan, Benjamin J.; Watson, Graeme W. [School of Chemistry, Trinity College, University of Dublin, Dublin 2 (Ireland)

    2009-12-15T23:59:59.000Z

    We have investigated the formation of native defects in anatase TiO{sub 2} using density functional theory (DFT) modified with on-site Coulomb terms (DFT+U) applied to both Ti d and O p states. Oxygen vacancies and titanium interstitials are found to be deep donors that trap two and four electrons, with transition levels that explain the two features seen in deep level transient spectroscopy experiments. Titanium vacancies are deep acceptors accommodating four holes. Self-trapping of both electrons and holes is also predicted. In all cases both donor and acceptor trap states correspond to strongly localized small polarons, in agreement with experimental EPR data. Variation in defect formation energies with stoichiometry explains the poor hole-trapping of reduced TiO{sub 2}.

  11. 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

  12. Magnetically stimulated fluid flow patterns

    ScienceCinema (OSTI)

    Martin, Jim; Solis, Kyle

    2014-08-06T23:59:59.000Z

    Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.

  13. Magnetically stimulated fluid flow patterns

    SciTech Connect (OSTI)

    Martin, Jim; Solis, Kyle

    2014-03-06T23:59:59.000Z

    Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.

  14. 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.

  15. 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.

  16. 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.

  17. I. Top 20 TA Traps 123 II. Team Meeting Guidelines 125

    E-Print Network [OSTI]

    Minnesota, University of

    Chapter 5 Other Teaching Resources Page I. Top 20 TA Traps 123 II. Team Meeting Guidelines 125 III.0.0 143 IX. Useful Information for TAs 147 #12;#12;Page 123 I. Top 20 TA Traps This list has been compiled by mentor TAs to help you avoid some common pitfalls of being a TA. These are the top twenty things TAs do

  18. 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

    AbstractThe 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...

  19. An ion ring in a linear multipole trap for optical frequency metrology C. Champenois, # M. Marciante, J. PedregosaGutierrez, M. Houssin, and M. Knoop

    E-Print Network [OSTI]

    Recanati, Catherine

    An ion ring in a linear multipole trap for optical frequency metrology C. Champenois, # M­Kitamachi, Koganei, Tokyo 184­8795, Japan (Dated: May 31, 2010) A ring crystal of ions trapped in a linear multipole multipole traps where the electric field amplitude is almost null in the center part of the trap [13]. Large

  20. Immobilization of Cesium Traps from the BN-350 Fast Reactor (Aktau, Kazakhstan)

    SciTech Connect (OSTI)

    J. A. Michelbacher; C. Knight; O. G. Romanenko; I. L. Tazhibaeva; I. L. Yakovlev; A. V. Rovneyko; V. I. Maev; D. Wells; A. Herrick

    2011-03-01T23:59:59.000Z

    During BN-350 reactor operations and also during the initial stages of decommissioning, cesium traps were used to decontaminate the reactors primary sodium coolant. Two different types of carbon-based trap were used the MAVR series, low ash granulated graphite adsorber (LAG) contained in a carrier designed to be inserted into the reactor core during shutdown; and a series of ex-reactor trap accumulators(TAs) which used reticulated vitreous carbon (RVC) to reduce Cs-137 levels in the sodium after final reactor shutdown. In total four MAVRs and seven TAs were used at BN-350 to remove an estimated cumulative 755 TBq of cesium. The traps, which also contain residual sodium, need to be immobilized in an appropriate way to allow them to be consigned as waste packages for long term storage and, ultimately, disposal. The present paper reports on the current status of the implementation phase, with particular reference to the work done to date on the trap accumulators, which have the most similarity with the cesium traps used at other reactors.

  1. Deuterium trapping at defects created with neutron and ion irradiations in tungsten

    SciTech Connect (OSTI)

    Y. Hatano; M. Shimada; T. Otsuka; Y. Oya; V.Kh. Alimov; M. Hara; J. Shi; M. Kobayashi; T. Oda; G. Cao; K. Okuno; T. Tanaka; K. Sugiyama; J. Roth; B. Tyburska-Pschel; J. Dorner; N. Yoshida; N. Futagami; H. Watanabe; M. Hatakeyama; H. Kurishita; M. Sokolov; Y. Katoh

    2013-07-01T23:59:59.000Z

    The effects of neutron and ion irradiations on deuterium (D) retention in tungsten (W) were investigated. Specimens of pure W were irradiated with neutrons to 0.3 dpa at around 323 K and then exposed to high-flux D plasma at 473 and 773 K. The concentration of D significantly increased by neutron irradiation and reached 0.8 at% at 473 K and 0.4 at% at 773 K. Annealing tests for the specimens irradiated with 20 MeV W ions showed that the defects which play a dominant role in the trapping at high temperature were stable at least up to 973 K, while the density decreased at temperatures equal to or above 1123 K. These observations of the thermal stability of traps and the activation energy for D detrapping examined in a previous study (1.8 eV) indicated that the defects which contribute predominantly to trapping at 773 K were small voids. The higher concentration of trapped D at 473 K was explained by additional contributions of weaker traps. The release of trapped D was clearly enhanced by the exposure to atomic hydrogen at 473 K, though higher temperatures are more effective for using this effect for tritium removal in fusion reactors.

  2. 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.

  3. 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...

  4. Parallel flow diffusion battery

    DOE Patents [OSTI]

    Yeh, H.C.; Cheng, Y.S.

    1984-01-01T23:59:59.000Z

    A parallel flow diffusion battery for determining the mass distribution of an aerosol has a plurality of diffusion cells mounted in parallel to an aerosol stream, each diffusion cell including a stack of mesh wire screens of different density.

  5. Optical flow switching

    E-Print Network [OSTI]

    Chan, Vincent W. S.

    Present-day networks are being challenged by dramatic increases in bandwidth demand of emerging applications. We will explore a new transport, ldquooptical flow switchingrdquo, that will enable significant growth and ...

  6. Olefin Autoxidation in Flow

    E-Print Network [OSTI]

    Neuenschwander, Ulrich

    Handling hazardous multiphase reactions in flow brings not only safety advantages but also significantly improved performance, due to better mass transfer characteristics. In this paper, we present a continuous microreactor ...

  7. Conjugate flow action functionals

    SciTech Connect (OSTI)

    Venturi, Daniele, E-mail: daniele-venturi@brown.edu [Division of Applied Mathematics, Brown University, Rhode Island 02912 (United States)] [Division of Applied Mathematics, Brown University, Rhode Island 02912 (United States)

    2013-11-15T23:59:59.000Z

    We present a new general framework to construct an action functional for a non-potential field theory. The key idea relies on representing the governing equations relative to a diffeomorphic flow of curvilinear coordinates which is assumed to be functionally dependent on the solution field. Such flow, which will be called the conjugate flow, evolves in space and time similarly to a physical fluid flow of classical mechanics and it can be selected in order to symmetrize the Gteaux derivative of the field equations with respect to suitable local bilinear forms. This is equivalent to requiring that the governing equations of the field theory can be derived from a principle of stationary action on a Lie group manifold. By using a general operator framework, we obtain the determining equations of such manifold and the corresponding conjugate flow action functional. In particular, we study scalar and vector field theories governed by second-order nonlinear partial differential equations. The identification of transformation groups leaving the conjugate flow action functional invariant could lead to the discovery of new conservation laws in fluid dynamics and other disciplines.

  8. U.S. Department of Energy Idaho National Engineering and Environmental...

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

    future lava flows inundating a random site within a VRZ can be constructed. Hackett and Smith (1994) estimated the general probability for lava flow inundation within each of the...

  9. Section 13: Flow control 1 Section 13: Flow control

    E-Print Network [OSTI]

    Kohlenbach, Ulrich

    Geometries for Energyefficient Flow Around Bodies Abstract 14:30 14:50: Elfriede Friedmann (Universitt

  10. Energy Flow Energy Flow Energy Flow A.Ukleja, T.Tymieniecka, I.Skillicorn 1 Azimuthal asymmetry

    E-Print Network [OSTI]

    Energy Flow Energy Flow Energy Flow A.Ukleja, T.Tymieniecka, I.Skillicorn 1 Azimuthal asymmetry using energy flow method Azimuthal angle distribution at Q2 >100 GeV2 Energy flow method.Ukleja on behalf of the ZEUS Collaboration #12; Energy Flow Energy Flow Energy Flow A.Ukleja, T.Tymieniecka, I

  11. Integrated Fiber-Mirror Ion Trap for Strong Ion-Cavity Coupling

    E-Print Network [OSTI]

    Birgit Brandsttter; Andrew McClung; Klemens Schppert; Bernardo Casabone; Konstantin Friebe; Andreas Stute; Piet O. Schmidt; Christian Deutsch; Jakob Reichel; Rainer Blatt; Tracy E. Northup

    2013-11-27T23:59:59.000Z

    We present and characterize fiber mirrors and a miniaturized ion-trap design developed to integrate a fiber-based Fabry-Perot cavity (FFPC) with a linear Paul trap for use in cavity-QED experiments with trapped ions. Our fiber-mirror fabrication process not only enables the construction of FFPCs with small mode volumes, but also allows us to minimize the influence of the dielectric fiber mirrors on the trapped-ion pseudopotential. We discuss the effect of clipping losses for long FFPCs and the effect of angular and lateral displacements on the coupling efficiencies between cavity and fiber. Optical profilometry allows us to determine the radii of curvature and ellipticities of the fiber mirrors. From finesse measurements we infer a single-atom cooperativity of up to $12$ for FFPCs longer than $200 \\mu$m in length; comparison to cavities constructed with reference substrate mirrors produced in the same coating run indicates that our FFPCs have similar scattering losses. We discuss experiments to anneal fiber mirrors and explore the influence of the atmosphere under which annealing occurs on coating losses, finding that annealing under vacuum increases the losses for our reference substrate mirrors. Our unique linear Paul trap design provides clearance for such a cavity and is miniaturized to shield trapped ions from the dielectric fiber mirrors. We numerically calculate the trap potential in the absence of fibers. In the experiment additional electrodes can be used to compensate distortions of the potential due to the fibers. Home-built fiber feedthroughs connect the FFPC to external optics, and an integrated nanopositioning system affords the possibility of retracting or realigning the cavity without breaking vacuum.

  12. Study of the Natural Gas Hydrate 'Trap Zone' and the Methane Hydrate Potential in the Sverdrup Basin, Canada

    SciTech Connect (OSTI)

    Majorowicz, J. A. [Northern Geothermal Consult. (Canada)], E-mail: majorowi@show.ca; Hannigan, P. K.; Osadetz, K. G. [Geological Survey of Canada, Calgary (Canada)

    2002-06-15T23:59:59.000Z

    The methane hydrate stability zone beneath Sverdrup Basin has developed to a depth of 2 km underneath the Canadian Arctic Islands and 1 km below sea level under the deepest part of the inter-island sea channels. It is not, however, a continuous zone. Methane hydrates are detected in this zone, but the gas hydrate/free gas contact occurs rarely. Interpretation of well logs indicate that methane hydrate occurs within the methane stability zone in 57 of 150 analyzed wells. Fourteen wells show the methane hydrate/free gas contact. Analysis of the distribution of methane hydrate and hydrate/gas contact occurrences with respect to the present methane hydrate stability zone indicate that, in most instances, the detected methane hydrate occurs well above the base of methane hydrate stability. This relationship suggests that these methane hydrates were formed in shallower strata than expected with respect to the present hydrate stability zone from methane gases which migrated upward into hydrate trap zones. Presently, only a small proportion of gas hydrate occurrences occur in close proximity to the base of predicted methane hydrate stability. The association of the majority of detected hydrates with deeply buried hydrocarbon discoveries, mostly conventional natural gas accumulations, or mapped seismic closures, some of which are dry, located in structures in western and central Sverdrup Basin, indicate the concurring relationship of hydrate occurrence with areas of high heat flow. Either present-day or paleo-high heat flows are relevant. Twenty-three hydrate occurrences coincide directly with underlying conventional hydrocarbon accumulations. Other gas hydrate occurrences are associated with structures filled with water with evidence of precursor hydrocarbons that were lost because of upward leakage.

  13. Does Water Content or Flow Rate Control Colloid Transport in Unsaturated Porous Media?

    SciTech Connect (OSTI)

    Thorsten Knappenberger; Markus Flury; Earl D. Mattson; James B. Harsh

    2014-03-01T23:59:59.000Z

    Mobile colloids can play an important role in contaminant transport in soils: many contaminants exist in colloidal form, and colloids can facilitate transport of otherwise immobile contaminants. In unsaturated soils, colloid transport is, among other factors, affected by water content and flow rate. Our objective was to determine whether water content or flow rate is more important for colloid transport. We passed negatively charged polystyrene colloids (220 nm diameter) through unsaturated sand-filled columns under steady-state flow at different water contents (effective water saturations Se ranging from 0.1 to 1.0, with Se = (? ?r)/(?s ?r)) and flow rates (pore water velocities v of 5 and 10 cm/min). Water content was the dominant factor in our experiments. Colloid transport decreased with decreasing water content, and below a critical water content (Se < 0.1), colloid transport was inhibited, and colloids were strained in water films. Pendular ring and water film thickness calculations indicated that colloids can move only when pendular rings are interconnected. The flow rate affected retention of colloids in the secondary energy minimum, with less colloids being trapped when the flow rate increased. These results confirm the importance of both water content and flow rate for colloid transport in unsaturated porous media and highlight the dominant role of water content.

  14. Development of PM trap system for urban buses

    SciTech Connect (OSTI)

    Kumagai, Yasuaki; Nakashima, Naohisa; Miyata, Osamu; Ikeda, Tatuya

    1996-09-01T23:59:59.000Z

    In response to stringent particulate matter (PM) emission regulations worldwide, developments of diesel particulate filter (DPF) continue apace in addition to engine modification for PM reduction. Particularly with buses used in urban areas, reduction methods in black smoke emissions are being researched in addition to the efforts to satisfy the aforementioned PM regulations. The system described in this paper was developed for use mainly with buses in large urban concentrations. The system consists of both wall-flow monolith filters for filtration of PM emissions and electric heaters for regeneration. A key feature of this system is that exhaust gas is used for effective combustion of PM during regeneration. Optimization of the exhaust gas flow rate drawn into the filter under regeneration has resulted in regeneration efficiency comparable with those achieved using air pumps. The difficulty of putting DPF systems to practical use has been due to cracking and melting of filters caused by excessive PM accumulation and subsequent increases in temperature in excess of tolerable levels. To prevent these problems, some means of controlling the accumulated PM mass was required. Since bus routes in large urban concentrations follow common patterns, the mass of PM accumulated over a given time period is more or less constant. Thus, the amount of PM accumulated over a given time period can be estimated easily and filter damage can be prevented.

  15. Piezoelectric axial flow microvalve

    SciTech Connect (OSTI)

    Gemmen, Randall; Thornton, Jimmy; Vipperman, Jeffrey S.; Clark, William W.

    2007-01-09T23:59:59.000Z

    This invention is directed to a fuel cell operable with a quantity of fuel and a quantity of an oxidizer to produce electrical power, the fuel cell including a fuel cell body including a labyrinth system structured to permit the fuel and the oxidizer to flow therethrough; at least a first catalyst in fluid communication with the labyrinth; and at least a first microvalve operably disposed within at least a portion of the labyrinth. The microvalve utilizes a deflectable member operable upon the application of a voltage from a voltage source. The microvalve includes an elongated flow channel formed therein and extending substantially longitudinally between the first and second ends to permit substantially longitudinal flow of the fluid therethrough and between the first and second ends; and the deflectable member disposed on the valve body, the deflectable member including at least a first piezoelectric portion that is piezoelectrically operable to deflect the deflectable member between an open position and a closed position upon the application of a voltage, the deflectable member in the closed position being operable to resist the flow of the fluid through the flow channel.

  16. Particle trap to sheath non-binding contact for a gas-insulated transmission line having a corrugated outer conductor

    DOE Patents [OSTI]

    Fischer, William H. (Pittsburgh, PA)

    1984-04-24T23:59:59.000Z

    A non-binding particle trap to outer sheath contact for use in gas insulated transmission lines having a corrugated outer conductor. The non-binding feature of the contact according to the teachings of the invention is accomplished by having a lever arm rotatably attached to a particle trap by a pivot support axis disposed parallel to the direction of travel of the inner conductor/insulator/particle trap assembly.

  17. Particle trap to sheath contact for a gas-insulated transmission line having a corrugated outer conductor

    DOE Patents [OSTI]

    Fischer, William H. (Pittsburgh, PA); Cookson, Alan H. (Pittsburgh, PA); Yoon, Kue H. (Pittsburgh, PA)

    1984-04-10T23:59:59.000Z

    A particle trap to outer elongated conductor or sheath contact for gas-insulated transmission lines. The particle trap to outer sheath contact of the invention is applicable to gas-insulated transmission lines having either corrugated or non-corrugated outer sheaths. The contact of the invention includes an electrical contact disposed on a lever arm which in turn is rotatably disposed on the particle trap and biased in a direction to maintain contact between the electrical contact and the outer sheath.

  18. Understanding the dynamics of a two-phase flow (liquid and gas) has been studied quite extensively over the past. This problem is indeed of direct relevance for many areas such

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    be trapped on the ground because of the presence of an obstacle. The studied products were propane, butane set-up, and pressure storage. 1 INTRODUCTION In many chemical and process plants, gas are stored for the understanding of the flow inside the pipe. The net of pipes linking the storage and the nozzle are composed

  19. Gaseous Flows in Galaxies

    E-Print Network [OSTI]

    F. Combes

    2007-09-02T23:59:59.000Z

    The gas component plays a major role in the dynamics of spiral galaxies, because of its dissipative character, and its ability to exchange angular momentum with stars in the disk. Due to its small velocity dispersion, it triggers gravitational instabilities, and the corresponding non-axisymmetric patterns produce gravity torques, which mediate these angular momentum exchanges. When a srong bar pattern develops with the same pattern speed all over the disk, only gas inside corotation can flow towards the center. But strong bars are not long lived in presence of gas, and multiple-speed spiral patterns can develop between bar phases, and help the galaxy to accrete external gas flowing from cosmic filaments. The gas is then intermittently driven to the galaxy center, to form nuclear starbursts and fuel an active nucleus. The various time-scales of these gaseous flows are described.

  20. The uses of electron beam ion traps in the study of highly charged ions

    SciTech Connect (OSTI)

    Knapp, D.

    1994-11-02T23:59:59.000Z

    The Electron Beam Ion Trap (EBIT) is a relatively new tool for the study of highly charged ions. Its development has led to a variety of new experimental opportunities; measurements have been performed with EBITs using techniques impossible with conventional ion sources or storage rings. In this paper, I will highlight the various experimental techniques we have developed and the results we have obtained using the EBIT and higher-energy Super-EBIT built at the Lawrence Livermore National Laboratory. The EBIT employs a high-current-density electron beam to trap, ionize, and excite a population of ions. The ions can be studied in situ or extracted from the trap for external experiments. The trapped ions form an ionization-state equilibrium determined by the relative ionization and recombination rates. Ions of several different elements may simultaneously be present in the trap. The ions are nearly at rest, and, for most systems, all in their ground-state configurations. The electron-ion interaction energy has a narrow distribution and can be varied over a wide range. We have used the EBIT devices for the measurement of electron-ion interactions, ion structure, ion-surface interactions, and the behavior of low-density plasmas.

  1. 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.

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

    SciTech Connect (OSTI)

    Pud, S.; Li, J.; Offenhusser, A.; Vitusevich, S. A., E-mail: s.vitusevich@fz-juelich.de [Peter Grnberg Institute (PGI-8), Forschungszentrum Jlich, 52425 Jlich (Germany); Gasparyan, F. [Peter Grnberg Institute (PGI-8), Forschungszentrum Jlich, 52425 Jlich (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.

  3. Dislocation-related trap levels in nitride-based light emitting diodes

    SciTech Connect (OSTI)

    Venturi, Giulia; Castaldini, Antonio; Cavallini, Anna [Department of Physics and Astronomy, University of Bologna, Viale Berti Pichat 6/2, Bologna 40127 (Italy); Meneghini, Matteo; Zanoni, Enrico [Department of Information Engineering, University of Padova, via Gradenigo 6/B, Padova 35131 (Italy); Zhu, Dandan; Humphreys, Colin [Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS (United Kingdom)

    2014-05-26T23:59:59.000Z

    Deep level transient spectroscopy was performed on InGaN/GaN multiple quantum well light emitting diodes (LEDs) in order to determine the effect of the dislocation density on the deep intragap electronic levels. The LEDs were grown by metalorganic vapor phase epitaxy on GaN templates with a high dislocation density of 8 10{sup 9} cm{sup ?2} and a low dislocation density of 3 10{sup 8} cm{sup ?2}. Three trapping levels for electrons were revealed, named A, A1, and B, with energies E{sub A}???0.04?eV, E{sub A1}???0.13?eV, and E{sub B}???0.54?eV, respectively. The trapping level A has a much higher concentration in the LEDs grown on the template with a high density of dislocations. The logarithmic dependence of the peak amplitude on the bias pulse width for traps A and A1 identifies the defects responsible for these traps as associated with linearly arranged defects. We conclude that traps A and A1 are dislocation-related intragap energy levels.

  4. Bose-Einstein condensates with attractive 1/r interaction: The case of self-trapping

    E-Print Network [OSTI]

    I. Papadopoulos; P. Wagner; G. Wunner; J. Main

    2007-09-18T23:59:59.000Z

    Amplifying on a proposal by O'Dell et al. for the realization of Bose-Einstein condensates of neutral atoms with attractive $1/r$ interaction, we point out that the instance of self-trapping of the condensate, without external trap potential, is physically best understood by introducing appropriate "atomic" units. This reveals a remarkable scaling property: the physics of the condensate depends only on the two parameters $N^2 a/a_u$ and $\\gamma/N^2$, where $N$ is the particle number, $a$ the scattering length, $a_u$ the "Bohr" radius and $\\gamma$ the trap frequency in atomic units. We calculate accurate numerical results for self-trapping wave functions and potentials, for energies, sizes and peak densities, and compare with previous variational results. As a novel feature we point out the existence of a second solution of the extended Gross-Pitaevskii equation for negative scattering lengths, with and without trapping potential, which is born together with the ground state in a tangent bifurcation. This indicates the existence of an unstable collectively excited state of the condensate for negative scattering lengths.

  5. Multiphase cooling flows

    E-Print Network [OSTI]

    Peter A. Thomas

    1996-08-20T23:59:59.000Z

    I discuss the multiphase nature of the intracluster medium whose neglect can lead to overestimates of the baryon fraction of clusters by up to a factor of two. The multiphase form of the cooling flow equations are derived and reduced to a simple form for a wide class of self-similar density distributions. It is shown that steady-state cooling flows are \\emph{not} consistent with all possible emissivity profiles which can therefore be used as a test of the theory. In combination, they provide strong constraints on the mass distribution within the cooling radius.

  6. Coherent structures in ion temperature gradient turbulence-zonal flow

    SciTech Connect (OSTI)

    Singh, Rameswar, E-mail: rameswar.singh@lpp.polytechnique.fr [Laboratoire de Physique des Plasmas, Ecole Polytechnique, Route de Saclay, 91128 Palaiseau Cedex (France); Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); Singh, R. [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Kaw, P. [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); Grcan, . D. [Laboratoire de Physique des Plasmas, Ecole Polytechnique, Route de Saclay, 91128 Palaiseau Cedex (France); Diamond, P. H. [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); CMTFO and CASS, University of California, San Diego, California 92093 (United States)

    2014-10-15T23:59:59.000Z

    Nonlinear stationary structure formation in the coupled ion temperature gradient (ITG)-zonal flow system is investigated. The ITG turbulence is described by a wave-kinetic equation for the action density of the ITG mode, and the longer scale zonal mode is described by a dynamic equation for the m?=?n?=?0 component of the potential. Two populations of trapped and untrapped drift wave trajectories are shown to exist in a moving frame of reference. This novel effect leads to the formation of nonlinear stationary structures. It is shown that the ITG turbulence can self-consistently sustain coherent, radially propagating modulation envelope structures such as solitons, shocks, and nonlinear wave trains.

  7. Total current collapse in High-Voltage GaN MIS-HEMTs induced by Zener trapping D. Jin, J. Joh*, S. Krishnan*, N. Tipirneni*, S. Pendharkar* and J. A. del Alamo

    E-Print Network [OSTI]

    del Alamo, Jess A.

    Total current collapse in High-Voltage GaN MIS-HEMTs induced by Zener trapping D. Jin, J. Joh*, S collapse in GaN MIS-HEMTs for >600 V operation. Extreme trapping leading to total current collapse has been trapping ("Zener trapping") inside the AlGaN barrier or the GaN channel layers. The trapping takes place

  8. Light Trapping for High Efficiency Heterojunction Crystalline Si Solar Cells: Preprint

    SciTech Connect (OSTI)

    Wang, Q.; Xu, Y.; Iwaniczko, E.; Page, M.

    2011-04-01T23:59:59.000Z

    Light trapping plays an important role to achieve high short circuit current density (Jsc) and high efficiency for amorphous/crystalline Si heterojunction solar cells. Si heterojunction uses hydrogenated amorphous Si for emitter and back contact. This structure of solar cell posses highest open circuit voltage of 0.747 V at one sun for c-Si based solar cells. It also suggests that over 25% record-high efficiency is possible with further improvement of Jsc. Light trapping has two important tasks. The first one is to reduce the surface reflectance of light to zero for the solar spectrum that Si has a response. The second one is to increase the effective absorption length to capture all the photon. For Si heterojunction solar cell, surface texturing, anti-reflectance indium tin oxides (ITO) layer at the front and back are the key area to improve the light trapping.

  9. BPM Button Optimization to Minimize Distortion Due to Trapped Mode Heating

    SciTech Connect (OSTI)

    Cameron,P.; Blednyk, A.; Kosciuk, B.; Pinayev, I.; Ravindranath, I.; Singh, O

    2009-05-04T23:59:59.000Z

    The outer circumference of a BPM button and the inner circumference of the button housing comprise a transmission line. This transmission line typically presents an impedance of a few tens of ohms to the beam, and couples very weakly to the 50 ohm coaxial transmission line that comprises the signal path out of the button. The modes which are consequently excited and trapped often have quality factors of several hundred, permitting resonant excitation by the beam. The thermal distortion resulting from trapped mode heating is potentially problematic for achieving the high precision beam position measurements needed to provide the sub-micron beam position stability required by light source users. We present a button design that has been optimized via material selection and component geometry to minimize both the trapped mode heating and the resulting thermal distortion.

  10. Cooling the motion of a trapped atom with a cavity field

    E-Print Network [OSTI]

    Marc Bienert; Giovanna Morigi

    2012-11-07T23:59:59.000Z

    We theoretically analyze the cooling dynamics of an atom which is tightly trapped inside a high-finesse optical resonator. Cooling is achieved by suitably tailored scattering processes, in which the atomic dipole transition either scatters a cavity photon into the electromagnetic field external to the resonator, or performs a stimulated emission into the cavity mode, which then dissipates via the cavity mirrors. We identify the parameter regimes in which the atom center-of-mass motion can be cooled into the ground state of the external trap. We predict, in particular, that for high cooperativities interference effects mediated by the atomic transition may lead to higher efficiencies. The dynamics is compared with the cooling dynamics of a trapped atom inside a resonator studied in [Phys. Rev. Lett. 95, 143001, (2005)] where the atom, instead of the cavity, is driven by a laser field.

  11. Tapered optical fibers as tools for probing magneto-optical trap characteristics

    E-Print Network [OSTI]

    M. J. Morrissey; K. Deasy; Y. Wu; S. Chakrabarti; S. Nic Chormaic

    2009-03-17T23:59:59.000Z

    We present a novel technique for measuring the characteristics of a magneto-optical trap for cold atoms by monitoring the spontaneous emission from trapped atoms coupled into the guided mode of a tapered optical nanofiber. We show that the nanofiber is highly sensitive to very small numbers of atoms close to its surface. The size and shape of the MOT, determined by translating the cold atom cloud across the tapered fiber, is in excellent agreement with measurements obtained using the conventional method of fluorescence imaging using a CCD camera. The coupling of atomic fluorescence into the tapered fiber also allows us to monitor the loading and lifetime of the trap. The results are compared to those achieved by focusing the MOT fluorescence onto a photodiode and it was seen that the tapered fiber gives slightly longer loading and lifetime measurements due to the sensitivity of the fiber, even when very few atoms are present.

  12. Modeling and control of entanglement dynamics in laser cooling of trapped atoms

    E-Print Network [OSTI]

    Maryam Roghani; Heinz-Peter Breuer; Hanspeter Helm

    2011-08-01T23:59:59.000Z

    We discuss the dynamical behavior of the entanglement between the internal and the external degrees of freedom of a trapped atom in electromagnetically-induced transparency (EIT) laser cooling. It is shown that essential features of the intricate entanglement dynamics observed in full numerical simulations of the underlying quantum master equation can be understood in terms of a two-state model on the basis of Landau-Zener splittings in the atom-laser field Hamiltonian. An extension of this model to an effective non-Hermitian Hamiltonian is constructed which describes the decay of entanglement by spontaneous emission processes. We also discuss schemes for the control of entanglement and demonstrate that a permanent entanglement can be imprinted on trapped atoms through a rapid switch off of the driving fields. Finally, we point out fundamental distinctions between the entanglement created in EIT cooling and in the cooling scheme based on velocity-selective coherent population trapping.

  13. Off-resonance energy absorption in a linear Paul trap due to mass selective resonant quenching

    SciTech Connect (OSTI)

    Sivarajah, I.; Goodman, D. S.; Wells, J. E.; Smith, W. W. [Department of Physics, University of Connecticut, Storrs, Connecticut 06269 (United States)] [Department of Physics, University of Connecticut, Storrs, Connecticut 06269 (United States); Narducci, F. A. [Naval Air Systems Command, EO Sensors Division, Bldg 2187, Suite 3190 Patuxent River, Maryland 20670 (United States)] [Naval Air Systems Command, EO Sensors Division, Bldg 2187, Suite 3190 Patuxent River, Maryland 20670 (United States)

    2013-11-15T23:59:59.000Z

    Linear Paul traps (LPT) are used in many experimental studies such as mass spectrometry, atom-ion collisions, and ion-molecule reactions. Mass selective resonant quenching (MSRQ) is implemented in LPT either to identify a charged particle's mass or to remove unwanted ions from a controlled experimental environment. In the latter case, MSRQ can introduce undesired heating to co-trapped ions of different mass, whose secular motion is off resonance with the quenching ac field, which we call off-resonance energy absorption (OREA). We present simulations and experimental evidence that show that the OREA increases exponentially with the number of ions loaded into the trap and with the amplitude of the off-resonance external ac field.

  14. Structure and dynamics of ion clusters in linear octupole traps: Phase diagrams, chirality, and melting mechanisms

    SciTech Connect (OSTI)

    Yurtsever, E.; Onal, E. D.; Calvo, F. [Koc University, Rumelifeneriyolu, Sariyer, Istanbul TR-34450 (Turkey); LASIM, Universite de Lyon and CNRS UMR 5579, 43 Bd du 11 Novembre 1918, FR-69622 Villeurbanne Cedex (France)

    2011-05-15T23:59:59.000Z

    The stable structures and melting dynamics of clusters of identical ions bound by linear octupole radiofrequency traps are theoretically investigated by global optimization methods and molecular dynamics simulations. By varying the cluster sizes in the range of 10-1000 ions and the extent of trap anisotropy by more than one order of magnitude, we find a broad variety of stable structures based on multiple rings at small sizes evolving into tubular geometries at large sizes. The binding energy of these clusters is well represented by two contributions arising from isotropic linear and octupolar traps. The structures generally exhibit strong size effects, and chiral arrangements spontaneously emerge in many crystals. Sufficiently large clusters form nested, coaxial tubes with different thermal stabilities. As in isotropic octupolar clusters, the inner tubes melt at temperatures that are lower than the overall melting point.

  15. Improving Ion Mobility Measurement Sensitivity by Utilizing Helium in an Ion Funnel-Trap

    SciTech Connect (OSTI)

    Ibrahim, Yehia M.; Garimella, Venkata BS; Tolmachev, Aleksey V.; Baker, Erin Shammel; Smith, Richard D.

    2014-05-01T23:59:59.000Z

    Ion mobility instruments that utilize nitrogen as buffer gas are often preceded by an ion trap and accumulation region that also uses nitrogen, and for different inert gases no significant effects upon performance are expected for IMS of larger ions. However, we have observed significantly improved performance for an ion funnel trap upon adding helium; the signal intensities for higher m/z species were improved by more than an order of magnitude compared to using pure nitrogen. The effect of helium upon IMS resolving power was also studied by introducing a He/N2 gas mixture into the drift cell, and in some cases a slight improvement was observed compared to pure N2. The improvement in signal can be largely attributed to faster and more efficient ion ejection into the drift tube from the ion funnel trap.

  16. Cold inelastic collisions between lithium and cesium in a two-species magneto-optical trap

    E-Print Network [OSTI]

    Schlder, U; Schnemann, U; Grimm, R; Weidemller, M

    1999-01-01T23:59:59.000Z

    We investigate collisional properties of lithium and cesium which are simultaneously confined in a combined magneto-optical trap. Trap-loss collisions between the two species are comprehensively studied. Different inelastic collision channels are identified, and inter-species rate coefficients as well as cross sections are determined. It is found that loss rates are independent of the optical excitation of Li, as a consequence of the repulsive Li$^*$-Cs interaction. Li and Cs loss by inelastic inter-species collisions can completely be attributed to processes involving optically excited cesium (fine-structure changing collisions and radiative escape). By lowering the trap depth for Li, an additional loss channel of Li is observed which results from ground-state Li-Cs collisions changing the hyperfine state of cesium.

  17. Impact of the Meissner effect on magnetic micro traps for neutral atoms near superconducting thin films

    E-Print Network [OSTI]

    D. Cano; B. Kasch; H. Hattermann; D. Koelle; R. Kleiner; C. Zimmermann; J. Fortgh

    2008-08-21T23:59:59.000Z

    We theoretically evaluate changes in the magnetic potential arising from the magnetic field near superconducting thin films. An example of an atom chip based on a three-wire configuration has been simulated in the superconducting and the normal conducting state. Inhomogeneous current densities within the superconducting wires were calculated using an energy-minimization routine based on the London theory. The Meissner effect causes changes to both trap position and oscillation frequencies at short distances from the superconducting surface. Superconducting wires produce much shallower micro traps than normal conducting wires. The results presented in this paper demonstrate the importance of taking the Meissner effect into account when designing and carrying out experiments on magnetically trapped neutral atoms near superconducting surfaces.

  18. 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.

  19. Enhanced Efficiency of Light-Trapping Nanoantenna Arrays for Thin Film Solar Cells

    E-Print Network [OSTI]

    Simovski, Constantin R; Voroshilov, Pavel M; Guzhva, Michael E; Belov, Pavel A; Kivshar, Yuri S

    2013-01-01T23:59:59.000Z

    We suggest a novel concept of efficient light-trapping structures for thin-film solar cells based on arrays of planar nanoantennas operating far from plasmonic resonances. The operation principle of our structures relies on the excitation of chessboard-like collective modes of the nanoantenna arrays with the field localized between the neighboring metal elements. We demonstrated theoretically substantial enhancement of solar-cell short-circuit current by the designed light-trapping structure in the whole spectrum range of the solar-cell operation compared to conventional structures employing anti-reflecting coating. Our approach provides a general background for a design of different types of efficient broadband light-trapping structures for thin-film solar-cell technologically compatible with large-area thin-film fabrication techniques.

  20. Flow cytometry apparatus

    DOE Patents [OSTI]

    Pinkel, Daniel (Walnut Creek, CA)

    1991-01-01T23:59:59.000Z

    An obstruction across the flow chamber creates a one dimensional convergence of a sheath fluid. A passageway in the construction directs flat cells near to the area of one dimensional convergence in the sheath fluid to provide proper orientation of flat cells at fast rates.