Sample records for atom trap trace

  1. 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...

  2. Atom trap trace analysis of krypton isotopes

    SciTech Connect (OSTI)

    Bailey, K.; Chen, C. Y.; Du, X.; Li, Y. M.; Lu, Z.-T.; O'Connor, T. P.; Young, L.

    1999-11-17T23:59:59.000Z

    A new method of ultrasensitive isotope trace analysis has been developed. This method, based on the technique of laser manipulation of neutral atoms, has been used to count individual {sup 85}Kr and {sup 81}Kr atoms present in a natural krypton gas sample with isotopic abundances in the range of 10{sup {minus}11} and 10{sup {minus}13}, respectively. This method is free of contamination from other isotopes and elements and can be applied to several different isotope tracers for a wide range of applications. The demonstrated detection efficiency is 1 x 10{sup {minus}7}. System improvements could increase the efficiency by many orders of magnitude.

  3. 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.

  4. An atom trap trace analysis (ATTA) system for measuring ultra-low contamination by krypton in

    E-Print Network [OSTI]

    Zelevinsky, Tanya

    An atom trap trace analysis (ATTA) system for measuring ultra-low contamination by krypton in xenon ultra-low contamination by krypton in xenon dark matter detectors Tae Hyun Yoon The XENON dark matter analysis (ATTA) device to detect the ultra-low kryp- ton concentration in the xenon target. This project

  5. Atom Trap Trace Analysis at ANL | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurTheBrookhaven NationalRegionals » HighAbstractsAprilArgonneArkansasAtom Trap

  6. 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 ...

  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. 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.

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. 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

  14. 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

  15. Fast optimal frictionless atom cooling in harmonic traps

    E-Print Network [OSTI]

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

    2009-10-05T23:59:59.000Z

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

  16. 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.

  17. 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...

  18. 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.

  19. Advanced Gasification Mercury/Trace Metal Control with Monolith Traps

    SciTech Connect (OSTI)

    Michael L. Swanson; Grant E. Dunham; Mark A. Musich

    2007-02-01T23:59:59.000Z

    Three potential additives for controlling mercury emissions from syngas at temperatures ranging from 350 to 500 F (177 to 260 C) were developed. Current efforts are being directed at increasing the effective working temperature for these sorbents and also being able to either eliminate any potential mercury desorption or trying to engineer a trace metal removal system that can utilize the observed desorption process to repeatedly regenerate the same sorbent monolith for extended use. Project results also indicate that one of these same sorbents can also successfully be utilized for arsenic removal. Capture of the hydrogen selenide in the passivated tubing at elevated temperatures has resulted in limited results on the effective control of hydrogen selenide with these current sorbents, although lower-temperature results are promising. Preliminary economic analysis suggests that these Corning monoliths potentially could be more cost-effective than the conventional cold-gas (presulfided activated carbon beds) technology currently being utilized. Recent Hg-loading results might suggest that the annualized costs might be as high as 2.5 times the cost of the conventional technology. However, this annualized cost does not take into account the significantly improved thermal efficiency of any plant utilizing the warm-gas monolith technology currently being developed.

  20. Heating of trapped ultracold atoms by collapse dynamics

    E-Print Network [OSTI]

    Franck Laloë; William J. Mullin; Philip Pearle

    2014-11-12T23:59:59.000Z

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

  1. Advanced Gasification Mercury/Trace Metal Control with Monolith Traps

    SciTech Connect (OSTI)

    Musich, Mark; Swanson, Michael; Dunham, Grant; Stanislowski, Joshua

    2010-10-05T23:59:59.000Z

    Two Corning monoliths and a non-carbon-based material have been identified as potential additives for mercury capture in syngas at temperatures above 400°F and pressure of 600 psig. A new Corning monolith formulation, GR-F1-2189, described as an active sample appeared to be the best monolith tested to date. The Corning SR Liquid monolith concept continues to be a strong candidate for mercury capture. Both monolith types allowed mercury reduction to below 5-?g/m{sup 3} (~5 ppb), a current U.S. Department of Energy (DOE) goal for trace metal control. Preparation methods for formulating the SR Liquid monolith impacted the ability of the monolith to capture mercury. The Energy & Environmental Research Center (EERC)-prepared Noncarbon Sorbents 1 and 2 appeared to offer potential for sustained and significant reduction of mercury concentration in the simulated fuel gas. The Noncarbon Sorbent 1 allowed sustained mercury reduction to below 5-?g/m{sup 3} (~5 ppb). The non-carbon-based sorbent appeared to offer the potential for regeneration, that is, desorption of mercury by temperature swing (using nitrogen and steam at temperatures above where adsorption takes place). A Corning cordierite monolith treated with a Group IB metal offered limited potential as a mercury sorbent. However, a Corning carbon-based monolith containing prereduced metallic species similar to those found on the noncarbon sorbents did not exhibit significant or sustained mercury reduction. EERC sorbents prepared with Group IB and IIB selenide appeared to have some promise for mercury capture. Unfortunately, these sorbents also released Se, as was evidenced by the measurement of H2Se in the effluent gas. All sorbents tested with arsine or hydrogen selenide, including Corning monoliths and the Group IB and IIB metal-based materials, showed an ability to capture arsine or hydrogen selenide at 400°F and 600 psig. Based on current testing, the noncarbon metal-based sorbents appear to be the most effective arsine and hydrogen selenide sorbents. The noncarbon sorbent was able to reduce the concentration to 0 ppb from a starting concentration of 120 ppb. This compares to the target value of 5 ppb (~17?g/m{sup 3}). The EERC-prepared metal-based pellet and coprecipitate sorbents exhibited arsine reductions of 90% or greater, being below 10 ppb. Corning SR Liquid monoliths exhibited brief periods (<1 hour) of attaining 90% arsine reduction but were able to achieve greater than 80% reduction for several hours. With respect to hydrogen selenide, all Group IB and IIB metal-based sorbents tested exhibited 100% reduction from an inlet concentration of approximately 400 ppb. Corning SR Liquid monoliths exhibited an 82% reduction when two monoliths were tested simultaneously in series.

  2. ADVANCED GASIFICATION MERCURY/TRACE METAL CONTROL WITH MONOLITH TRAPS

    SciTech Connect (OSTI)

    Mark A. Musich; Michael L. Swanson; Grant E. Dunham; Joshua J. Stanislowski

    2010-07-31T23:59:59.000Z

    Two Corning monoliths and a non-carbon-based material have been identified as potential additives for mercury capture in syngas at temperatures above 400°F and pressure of 600 psig. A new Corning monolith formulation, GR-F1-2189, described as an active sample appeared to be the best monolith tested to date. The Corning SR Liquid monolith concept continues to be a strong candidate for mercury capture. Both monolith types allowed mercury reduction to below 5-?g/m3 (~5 ppb), a current U.S. Department of Energy (DOE) goal for trace metal control. Preparation methods for formulating the SR Liquid monolith impacted the ability of the monolith to capture mercury. The Energy & Environmental Research Center (EERC)-prepared Noncarbon Sorbents 1 and 2 appeared to offer potential for sustained and significant reduction of mercury concentration in the simulated fuel gas. The Noncarbon Sorbent 1 allowed sustained mercury reduction to below 5-?g/m3 (~5 ppb). The non-carbon-based sorbent appeared to offer the potential for regeneration, that is, desorption of mercury by temperature swing (using nitrogen and steam at temperatures above where adsorption takes place). A Corning cordierite monolith treated with a Group IB metal offered limited potential as a mercury sorbent. However, a Corning carbon-based monolith containing prereduced metallic species similar to those found on the noncarbon sorbents did not exhibit significant or sustained mercury reduction. EERC sorbents prepared with Group IB and IIB selenide appeared to have some promise for mercury capture. Unfortunately, these sorbents also released Se, as was evidenced by the measurement of H2Se in the effluent gas. All sorbents tested with arsine or hydrogen selenide, including Corning monoliths and the Group IB and IIB metal-based materials, showed an ability to capture arsine or hydrogen selenide at 400°F and 600 psig. Based on current testing, the noncarbon metal-based sorbents appear to be the most effective arsine and hydrogen selenide sorbents. The noncarbon sorbent was able to reduce the concentration to 0 ppb from a starting concentration of 120 ppb. This compares to the target value of 5 ppb (~17?g/m3). The EERC-prepared metal-based pellet and coprecipitate sorbents exhibited arsine reductions of 90% or greater, being below 10 ppb. Corning SR Liquid monoliths exhibited brief periods (<1 hour) of attaining 90% arsine reduction but were able to achieve greater than 80% reduction for several hours. With respect to hydrogen selenide, all Group IB and IIB metal-based sorbents tested exhibited 100% reduction from an inlet concentration of approximately 400 ppb. Corning SR Liquid monoliths exhibited an 82% reduction when two monoliths were tested simultaneously in series.

  3. Resonant interaction of trapped cold atoms with a magnetic cantilever tip

    E-Print Network [OSTI]

    Montoya, Cris; Geraci, Andrew A; Eardley, Matthew; Moreland, John; Hollberg, Leo; Kitching, John

    2015-01-01T23:59:59.000Z

    Magnetic resonance in an ensemble of laser-cooled trapped Rb atoms is excited using a micro- cantilever with a magnetic tip. The cantilever is mounted on a multi-layer chip designed to capture, cool, and magnetically transport cold atoms. The coupling is observed by measuring the loss from a magnetic trap as the oscillating cantilever induces Zeeman state transitions in the atoms. Interfacing cold atoms with mechanical devices could enable probing and manipulating atomic spins with nanometer spatial resolution and single-spin sensitivity, leading to new capabilities in quantum computation, quantum simulation, or precision sensing.

  4. Resonant interaction of trapped cold atoms with a magnetic cantilever tip

    E-Print Network [OSTI]

    Cris Montoya; Jose Valencia; Andrew A. Geraci; Matthew Eardley; John Moreland; Leo Hollberg; John Kitching

    2015-03-26T23:59:59.000Z

    Magnetic resonance in an ensemble of laser-cooled trapped Rb atoms is excited using a micro- cantilever with a magnetic tip. The cantilever is mounted on a multi-layer chip designed to capture, cool, and magnetically transport cold atoms. The coupling is observed by measuring the loss from a magnetic trap as the oscillating cantilever induces Zeeman state transitions in the atoms. Interfacing cold atoms with mechanical devices could enable probing and manipulating atomic spins with nanometer spatial resolution and single-spin sensitivity, leading to new capabilities in quantum computation, quantum simulation, or precision sensing.

  5. Deep superconducting magnetic traps for neutral atoms and molecules J. G. E. Harris,a)

    E-Print Network [OSTI]

    Harris, Jack

    2003 We describe the design, construction and performance of three realizations of a high of the coils into a cryogenic vacuum environment suitable for producing cold atoms and molecules. © 2004 atomic vapors away from material walls, thereby breaking thermal contact be- tween the trapped atoms

  6. 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.

  7. 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.

  8. Semilinear response for the heating rate of cold atoms in vibrating traps

    E-Print Network [OSTI]

    Cohen, Doron

    OFFPRINT Semilinear response for the heating rate of cold atoms in vibrating traps A. Stotland, D;Europhysics Letters (EPL) has a new online home at www.epljournal.org Take a look for the latest journal news.epljournal.org doi: 10.1209/0295-5075/86/10004 Semilinear response for the heating rate of cold atoms in vibrating

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

    E-Print Network [OSTI]

    Srivastava, Rajendra P.

    1978-06-01T23:59:59.000Z

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

  10. 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.

  11. Velocity tuning of friction with two trapped atoms

    E-Print Network [OSTI]

    Gangloff, Dorian; Counts, Ian; Jhe, Wonho; Vuleti?, Vladan

    2015-01-01T23:59:59.000Z

    Friction is the basic, ubiquitous mechanical interaction between two surfaces that results in resistance to motion and energy dissipation. In spite of its technological and economic significance, our ability to control friction remains modest, and our understanding of the microscopic processes incomplete. At the atomic scale, mismatch between the two contacting crystal lattices can lead to a reduction of stick-slip friction (structural lubricity), while thermally activated atomic motion can give rise to a complex velocity dependence, and nearly vanishing friction at sufficiently low velocities (thermal lubricity). Atomic force microscopy has provided a wealth of experimental results, but limitations in the dynamic range, time resolution, and control at the single-atom level have hampered a full quantitative description from first principles. Here, using an ion-crystal friction emulator with single-atom, single substrate-site spatial resolution and single-slip temporal resolution, we measure the friction force...

  12. Nanowire photonic crystal waveguides for single-atom trapping and strong light-matter interactions

    SciTech Connect (OSTI)

    Yu, S.-P.; Hood, J. D.; Muniz, J. A.; Martin, M. J.; Hung, C.-L.; Kimble, H. J., E-mail: hjkimble@caltech.edu [Norman Bridge Laboratory of Physics 12-33, California Institute of Technology, Pasadena, California 91125 (United States); Institute for Quantum Information and Matter, California Institute of Technology, Pasadena, California 91125 (United States); Norte, Richard; Meenehan, Seán M.; Cohen, Justin D.; Painter, Oskar, E-mail: opainter@caltech.edu [Institute for Quantum Information and Matter, California Institute of Technology, Pasadena, California 91125 (United States); Thomas J. Watson, Sr., Laboratory of Applied Physics 128-95, California Institute of Technology, Pasadena, California 91125 (United States)

    2014-03-17T23:59:59.000Z

    We present a comprehensive study of dispersion-engineered nanowire photonic crystal waveguides suitable for experiments in quantum optics and atomic physics with optically trapped atoms. Detailed design methodology and specifications are provided, as are the processing steps used to create silicon nitride waveguides of low optical loss in the near-IR. Measurements of the waveguide optical properties and power-handling capability are also presented.

  13. ccsd-00005837,version2-10Jul2005 Partially ferromagnetic electromagnet for trapping and cooling neutral atoms to

    E-Print Network [OSTI]

    Boyer, Edmond

    lasers. INTRODUCTION The realization of Bose-Einstein condensates (BECs) of a dilute gas of trapped atoms of 87 Rb atoms to quantum degeneracy. Pure Bose-Einstein condensates containing 106 atoms are routinely, 9]. It is therefore expected that the use of Bose-Einstein condensed atoms will advance the field

  14. 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. Fortágh

    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.

  15. Fractal templates in the escape dynamics of trapped ultracold atoms Kevin A. Mitchell

    E-Print Network [OSTI]

    Steck, Daniel A.

    Fractal templates in the escape dynamics of trapped ultracold atoms Kevin A. Mitchell School nonlinear dynamics, we predict that fractal behavior can be seen in experimental escape data. These data can. This fractal pattern is particularly well resolved below the Bose-Einstein transition temperature--a direct

  16. Trapping and Manipulation of Isolated Atoms Using Nanoscale Plasmonic Structures D. E. Chang,1

    E-Print Network [OSTI]

    Heller, Eric

    - and nanopho- tonic structures [8­10] [see Fig. 1(a)]. Alternatively, hybrid quantum systems consisting, heating and decoherence rates acting on the trapped atom. DOI: 10.1103/PhysRevLett.103.123004 PACS numbers: 37.10.Gh, 42.50.Àp, 73.20.Mf, 78.67.Bf Much interest has recently been directed towards hybrid

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

    E-Print Network [OSTI]

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

    2015-02-04T23:59:59.000Z

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

  18. Preparation of a high concentration of lithium-7 atoms in a magneto-optical trap

    SciTech Connect (OSTI)

    Zelener, B. B., E-mail: bobozel@mail.ru; Saakyan, S. A.; Sautenkov, V. A. [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation); Manykin, E. A. [National Research Nuclear University “Moscow Engineering Physics Institute,” (Russian Federation); Zelener, B. V.; Fortov, V. E. [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation)

    2014-11-15T23:59:59.000Z

    This study is aimed at obtaining high concentration of optically cooled lithium-7 atoms for preparing strongly interacting ultracold plasma and Rydberg matter. A special setup has been constructed, in which two high-power semiconductor lasers are used to cool lithium-7 atoms in a magneto-optical trap. At an optimum detuning of the cooling laser frequency and a magnetic field gradient of 35 G/cm, the concentration of ultracold lithium-7 atoms reaches about 10{sup 11} cm{sup ?3}. Additional independent information about the concentration and number of ultracold lithium-7 atoms on different sublevels of the ground state was obtained by using of an additional probing laser.

  19. Laser scattering by density fluctuations of ultra-cold atoms in a magneto-optical trap

    E-Print Network [OSTI]

    J. T. Mendonça; H. Terças

    2011-04-06T23:59:59.000Z

    We study the spectrum of density fluctuations in the ultra-cold gas of neutral atoms, confined in a magneto-optical trap. We determine the corresponding amplitude and spectra of laser light scattered by this medium. We derive an expression for the dynamical structure function, by using a test particle method. We propose to use the collective laser scattering as a diagnostic method for the microscopic properties of the ultra-cold matter. This will also allow us to check on the atomic correlations which are mediated by the collective mean field inside the gas.

  20. Cavity cooling of a trapped atom using Electromagnetically-Induced Transparency

    E-Print Network [OSTI]

    Marc Bienert; Giovanna Morigi

    2011-12-01T23:59:59.000Z

    A cooling scheme for trapped atoms is proposed, which combines cavity-enhanced scattering and electromagnetically induced transparency. The cooling dynamics exploits a three-photon resonance, which combines laser and cavity excitations. It is shown that relatively fast ground-state cooling can be achieved in the Lamb-Dicke regime and for large cooperativity. Efficient ground-state cooling is found for parameters of ongoing experiments.

  1. Influence of coherent Raman scattering on coherent population trapping in atomic sodium vapor

    SciTech Connect (OSTI)

    Wong, Vincent; Bennink, Ryan S.; Marino, Alberto M.; Boyd, Robert W.; Stroud, C.R. Jr.; Narducci, F.A. [Institute of Optics, University of Rochester, Rochester, New York 14627 (United States); EO Sensors Division, Naval Air Systems Command, Patuxent River, Maryland 20670 (United States)

    2004-11-01T23:59:59.000Z

    We study how coherent Stokes and anti-Stokes Raman scattering influence coherent population trapping. In an experiment using an atomic sodium vapor cell we observe induced transparency, induced absorption, and gain features, all of subnatural linewidth. The electromagnetically induced resonance is a peak or a dip depending on which side of the optical transition the fields are tuned to, and thus whether coherent anti-Stokes Raman scattering or coherent Stokes Raman scattering is the dominant process.

  2. Fast nondestructive temperature measurement of two-electron atoms in a magneto-optical trap

    SciTech Connect (OSTI)

    Cristiani, Matteo; Valenzuela, Tristan; Gothe, Hannes; Eschner, Juergen [ICFO-Institut de Ciencies Fotoniques, Mediterranean Technology Park, E-08860 Castelldefels (Barcelona) (Spain)

    2010-06-15T23:59:59.000Z

    We extend the technique originally proposed by [Honda et al., Phys. Rev. A 59, R934 (1999)] to measure the temperature of ytterbium and alkaline-earth-metal atoms confined in a magneto-optical trap (MOT). The method is based on the analysis of excitation spectra obtained by probing the {sup 1}S{sub 0}{yields}{sup 3}P{sub 1} intercombination line. Thanks to a careful analysis and modeling of the effects caused by the MOT light on the probe transition we overcome the resolution and precision limits encountered in previous works. Ground-state light shift and Rabi broadening are measured and successfully compared with calculated values. This knowledge allows us to properly extract the Doppler contribution to the linewidth, thus obtaining a reliable measurement of the cloud temperature. We finally show how spectroscopy on free-falling atoms provides an alternative method to determine the sample temperature which resembles the standard time-of-flight technique.

  3. Alfvén ion-cyclotron instability in an axisymmetric trap with oblique injection of fast atoms

    SciTech Connect (OSTI)

    Tsidulko, Yu. A.; Chernoshtanov, I. S., E-mail: cherivn@ngs.ru [Russian Academy of Sciences, Budker Institute of Nuclear Physics (Russian Federation)

    2014-12-15T23:59:59.000Z

    Conditions for the onset of Alfvén ion-cyclotron instability and the spatial structure of unstable modes in an axisymmetric mirror trap with oblique injection of fast atoms are studied. It is shown that the main contribution to instability comes from the inverse population of ions in the velocity space domain into which atoms are injected. Using the distribution function of fast ions obtained by approximately solving the Fokker-Planck equation, the instability threshold in terms of ?{sub ?} is determined in the Wentzel-Kramers-Brillouin approximation as a function of the geometric parameters and the parameters of injection and target plasma. It is demonstrated that the stability threshold increases substantially when the radius of the hot plasma decreases to a size comparable with the Larmor radius of fast ions. It is shown that the perturbed fields near the axis and at the plasma periphery can rotate in opposite directions, which is important for the interpretation of experimental data.

  4. Combining red- and blue-detuned optical potentials to form a Lamb-Dicke trap for a single neutral atom

    E-Print Network [OSTI]

    Xiaodong He; Peng Xu; Jin Wang; Mingsheng Zhan

    2012-02-03T23:59:59.000Z

    We propose and demonstrate a scheme for strongly radially confining a single neutral atom in a bichromatic far-off resonance optical dipole trap(BFORT) . BFORT is composed of a blue-detuned Laguerre-Gaussian $LG^1_ 0$ beam and a red-detuned Gaussian beam. The trapping radial dimension of a single atom trapped in the Gaussian FORT can be greatly compressed by imposing a blue-detuned Laguerre-Gaussian $LG^1_ 0$ beam with moderate potential depth. By modulating the potential depth of the Gaussian FORT we observed that the resonant and parametric excitation of the oscillatory motion of a single atom in this BFORT and obtained the oscillation frequency that well fits prediction from the theoretical model. The frequency measurement shows that effective trapping dimension can be greatly sharper than that diffraction limited of microscopic objective we used. Then we show that the excess scattering rate due to imposing blue detuned light can be eliminated when single atoms is close to ground-state theoretically. So BFORT suits the purpose of acting as a Lamb-Dicke trap for further cooling a single neutral atom to motion ground-state and finding application in quantum information progressing.

  5. Production and trapping of radioactive atoms at the TRI\\muP facility

    E-Print Network [OSTI]

    E. Traykov; U. Dammalapati; S. De; O. C. Dermois; L. Huisman; K. Jungmann; W. Kruithof; A. J. Mol; C. J. G. Onderwater; A. Rogachevskiy; M. da Silva e Silva; M. Sohani; O. Versolato; L. Willmann; H. W. Wilschut

    2008-03-28T23:59:59.000Z

    The structures for the TRI$\\mu$P facility have been completed and commissioned. At the facility radioactive nuclides are produced to study fundamental interactions and symmetries. An important feature is the possibility to trap radioactive atoms in order to obtain and hold a pure substrate-free sample for precision measurements. In the TRI$\\mu$P facility a production target is followed by a magnetic separator, where radioactive isotopes are produced in inverse reaction kinematics. Separation up to 99.95% could be achieved for $^{21}$Na. A novel transmitting thermal ionizing device was developed to stop the energetic isotopes. Some 50% of stopped $^{21}$Na could be extracted and transported as low energy singly charged ions into a radio frequency quadrupole cooler and buncher with 35% transmission efficiency. The ions are transported lossless via a drift tube and a low energy electrostatic beam line into the experimental setup. Such ions can be neutralized on hot metal foils and the resulting atoms can be stored in a magneto-optical trap. The functioning of that principle was demonstrated with stable Na extracted from the thermal ionizer, radioactive beams will follow next.

  6. Exploring Ramsey-coherent population trapping atomic clock realized with pulsed microwave modulated laser

    SciTech Connect (OSTI)

    Yang, Jing; Yun, Peter [Key Laboratory of Atomic Frequency Standards, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China); Tian, Yuan; Tan, Bozhong [Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074 (China); Gu, Sihong, E-mail: shgu@wipm.ac.cn [Key Laboratory of Atomic Frequency Standards, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China); Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2014-03-07T23:59:59.000Z

    A scheme for a Ramsey-coherent population trapping (CPT) atomic clock that eliminates the acousto-optic modulator (AOM) is proposed and experimentally studied. Driven by a periodically microwave modulated current, the vertical-cavity surface-emitting laser emits a continuous beam that switches between monochromatic and multichromatic modes. Ramsey-CPT interference has been studied with this mode-switching beam. In eliminating the AOM, which is used to generate pulsed laser in conventional Ramsey-CPT atomic clock, the physics package of the proposed scheme is virtually the same as that of a conventional compact CPT atomic clock, although the resource budget for the electronics will slightly increase as a microwave switch should be added. By evaluating and comparing experimentally recorded signals from the two Ramsey-CPT schemes, the short-term frequency stability of the proposed scheme was found to be 46% better than the scheme with AOM. The experimental results suggest that the implementation of a compact Ramsey-CPT atomic clock promises better frequency stability.

  7. Blue-detuned evanescent field surface traps for neutral atoms based on mode interference in ultra-thin optical fibres

    E-Print Network [OSTI]

    G. Sague; A. Baade; A. Rauschenbeutel

    2008-06-24T23:59:59.000Z

    We present and analyze a novel concept for blue-detuned evanescent field surface traps for cold neutral atoms based on two-mode interference in ultra-thin optical fibres. When two or more transverse modes with the same frequency co-propagate in the fibre, their different phase velocities cause a stationary interference pattern to establish. Intensity minima of the evanescent field at any distance from the fibre surface can be created and an array of optical microtraps can thus be obtained in the evanescent field. We discuss three possible combinations of the lowest order modes, yielding traps at one to two hundred nanometres from the fibre surface which, using a few ten milliwatts of trapping laser power, have a depth on the order of 1 mK for caesium atoms and a trapping lifetime exceeding 100 seconds. The resulting trapping geometry is of particular interest because atoms in such microtrap arrays will be coupled to any additional field propagating in the fibre via the evanescent field, thereby realising ensembles of fibre-coupled atoms.

  8. Atom Trap Trace Analysis at ANL | U.S. DOE Office of Science...

    Office of Science (SC) Website

    by: DOE-NP, NSF-Earth Science Impactbenefit to spin-off field: Used to date old ground water, non-proliferation monitoring, Radio-Krypton Dating A new technique for counting very...

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

    E-Print Network [OSTI]

    Jordi Mur-Petit; Juan José García-Ripoll

    2015-01-12T23:59:59.000Z

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

  10. Strong interaction between light and a single trapped atom without a cavity

    E-Print Network [OSTI]

    Meng Khoon Tey; Zilong Chen; Syed Abdullah Aljunid; Brenda Chng; Florian Huber; Gleb Maslennikov; Christian Kurtsiefer

    2008-06-12T23:59:59.000Z

    Coupling of light to an atom at single quanta level with high probability is a building block for many quantum information processing protocols. It is commonly believed that efficient coupling is only achievable with the assistance of a cavity. Here, we report on an observation of substantial coupling between a light beam and a single $^{87}$Rb atom in a direct extinction measurement by focusing light to a small spot with a single lens. Our result opens a new perspective on processing quantum information carried by light using atoms, and is important to many ongoing experiments that require strong coupling of single photons to an atom in free space.

  11. Photoionization of optically trapped ultracold atoms with a high-power light-emitting diode

    SciTech Connect (OSTI)

    Goetz, Simone; Hoeltkemeier, Bastian; Amthor, Thomas; Weidemueller, Matthias [Physikalisches Institut, Universitaet Heidelberg, Im Neuenheimer Feld 226, 69120 Heidelberg (Germany)

    2013-04-15T23:59:59.000Z

    Photoionization of laser-cooled atoms using short pulses of a high-power light-emitting diode (LED) is demonstrated. Light pulses as short as 30 ns have been realized with the simple LED driver circuit. We measure the ionization cross section of {sup 85}Rb atoms in the first excited state, and show how this technique can be used for calibrating efficiencies of ion detector assemblies.

  12. Fluorescence during Doppler cooling of a single trapped atom J. H. Wesenberg,* R. J. Epstein,

    E-Print Network [OSTI]

    . Leibfried, R. B. Blakestad, J. Britton, J. P. Home, W. M. Itano, J. D. Jost, E. Knill, C. Langer, R. Ozeri of this temperature measurement provides a way to measure atom heating rates by observing the temperature rise field. After cooling and heating effects related to micromotion were observed, these effects were

  13. 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 ...

  14. Long-range sound-mediated dark-soliton interactions in trapped atomic condensates

    SciTech Connect (OSTI)

    Allen, A. J.; Jackson, D. P.; Barenghi, C. F.; Proukakis, N. P. [School of Mathematics and Statistics, Newcastle University, Newcastle upon Tyne, NE1 7RU (United Kingdom)

    2011-01-15T23:59:59.000Z

    A long-range soliton interaction is discussed whereby two or more dark solitons interact in an inhomogeneous atomic condensate, modifying their respective dynamics via the exchange of sound waves without ever coming into direct contact. An idealized double-well geometry is shown to yield perfect energy transfer and complete periodic identity reversal of the two solitons. Two experimentally relevant geometries are analyzed which should enable the observation of this long-range interaction.

  15. 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 ...

  16. Tracing Noble Gas Radionuclides in the Environment

    E-Print Network [OSTI]

    P. Collon; W. Kutschera; Z. -T. Lu

    2004-02-11T23:59:59.000Z

    Trace analysis of radionuclides is an essential and versatile tool in modern science and technology. Due to their ideal geophysical and geochemical properties, long-lived noble gas radionuclides, in particular, 39Ar (t1/2 = 269 yr), 81Kr (t1/2 = 2.3x10^5 yr) and 85Kr (t1/2 = 10.8 yr), have long been recognized to have a wide range of important applications in Earth sciences. In recent years, significant progress has been made in the development of practical analytical methods, and has led to applications of these isotopes in the hydrosphere (tracing the flow of groundwater and ocean water). In this article, we introduce the applications of these isotopes and review three leading analytical methods: Low-Level Counting (LLC), Accelerator Mass Spectrometry (AMS) and Atom Trap Trace Analysis (ATTA).

  17. Atom-light interactions in ultracold anisotropic media

    E-Print Network [OSTI]

    Vengalattore, Mukund T., 1977-

    2005-01-01T23:59:59.000Z

    A series of studies on atom-light interactions in ultracold anisotropic media were conducted. Methods to trap ultracold neutral atoms in novel traps with widely tunable trap frequencies and anisotropies were investigated. ...

  18. 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.

  19. 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.

  20. 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.

  1. Geothermal: Sponsored by OSTI -- Trace metal characterization...

    Office of Scientific and Technical Information (OSTI)

    Trace metal characterization and speciation in geothermal effluent by multiple scanning anodic stripping voltammetry and atomic absorpotion analysis. Annual progress report...

  2. 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.

  3. arXiv:1101.0686v1[physics.atom-ph]4Jan2011 Characteristics of integrated magneto-optical traps

    E-Print Network [OSTI]

    on an isolated pyramid, with hand-wound coils generating the trapping magnetic field. This was later replaced, and because they are micro-fabricated it is easy to form several pyramid MOTs on the same chip. In this paper hydroxide to form concave pyramidal hollows. The sides of the pyramids range in length L from 4.2 mm down

  4. 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.

  5. 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...

  6. 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. ...

  7. atomic photoabsorption process: Topics by E-print Network

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

    individual sites within atom-trap arrays. Cecilia Muldoon; Lukas Brandt; Jian Dong; Dustin Stuart; Edouard Brainis; Matthew Himsworth; Axel Kuhn 2012-03-21 306 Atomic...

  8. Transport of atom packets in a train of Ioffe-Pritchard traps T. Lahaye, G. Reinaudi, Z. Wang, A. Couvert, and D. Gury-Odelin

    E-Print Network [OSTI]

    Guéry-Odelin, David

    cooling techniques, of a magnetically guided atomic beam on which evaporative cooling can then be applied Received 11 May 2006; published 28 September 2006 We demonstrate transport and evaporative cooling.1103/PhysRevA.74.033622 PACS number s : 03.75.Pp, 32.80.Pj The combination of laser cooling and evaporative

  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. Realization of a superconducting atom chip

    E-Print Network [OSTI]

    Thomas Nirrengarten; Angie Qarry; Cédric Roux; Andreas Emmert; Gilles Nogues; Michel Brune; Jean-Michel Raimond; Serge Haroche

    2006-10-09T23:59:59.000Z

    We have trapped rubidium atoms in the magnetic field produced by a superconducting atom chip operated at liquid Helium temperatures. Up to $8.2\\cdot 10^5$ atoms are held in a Ioffe-Pritchard trap at a distance of 440 $\\mu$m from the chip surface, with a temperature of 40 $\\mu$K. The trap lifetime reaches 115 s at low atomic densities. These results open the way to the exploration of atom--surface interactions and coherent atomic transport in a superconducting environment, whose properties are radically different from normal metals at room temperature.

  11. Loading and characterization of a printed-circuit-board atomic ion trap Kenneth R. Brown, Robert J. Clark, Jaroslaw Labaziewicz, Philip Richerme, David R. Leibrandt, and Isaac L. Chuang

    E-Print Network [OSTI]

    Richerme, Phil

    -dimensional 3D lay- ered planar traps 6­8 and the ability to integrate control electronics below the electrode of new trap geometries and ion shuttling techniques. In this Brief Report, we demonstrate the loading

  12. 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.

  13. 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

  14. 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 ...

  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. 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

  17. Accelerometer using atomic waves for space applications

    E-Print Network [OSTI]

    of Bose-Einstein condensation (BEC) of a dilute gas of trapped atoms in a single quantum state [18, 19, 20 of such devices in the field of navigation, surveying and analysis of earth structures. Matter-wave interferometry that the use of Bose-Einstein condensed atoms will bring the science of atom optics, and in particular atom

  18. 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  

  19. 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...

  20. 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...

  1. 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) ...

  2. 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 ...

  3. 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 ...

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

    SciTech Connect (OSTI)

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

    2014-10-07T23:59:59.000Z

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

  5. 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 ...

  6. analytical atomic spectrometry: Topics by E-print Network

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

    cooling of trapped atoms is described as a sequence of truncation of the high energy for arbitrary power-law potentials. The threshold density for accelerated evaporation...

  7. atomic transition arrays: Topics by E-print Network

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

    individual sites within atom-trap arrays. Cecilia Muldoon; Lukas Brandt; Jian Dong; Dustin Stuart; Edouard Brainis; Matthew Himsworth; Axel Kuhn 2012-03-21 412 Interstellar...

  8. 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...

  9. Calibration of a single atom detector for atomic micro chips

    E-Print Network [OSTI]

    A. Stibor; S. Kraft; T. Campey; D. Komma; A. Günther; J. Fortágh; C. J. Vale; H. Rubinsztein-Dunlop; C. Zimmermann

    2007-02-13T23:59:59.000Z

    We experimentally investigate a scheme for detecting single atoms magnetically trapped on an atom chip. The detector is based on the photoionization of atoms and the subsequent detection of the generated ions. We describe the characterization of the ion detector with emphasis on its calibration via the correlation of ions with simultaneously generated electrons. A detection efficiency of 47.8% (+-2.6%) is measured, which is useful for single atom detection, and close to the limit allowing atom counting with sub-Poissonian uncertainty.

  10. 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.

  11. 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.

  12. Symposium on atomic spectroscopy (SAS-83): abstracts and program

    SciTech Connect (OSTI)

    Not Available

    1983-09-01T23:59:59.000Z

    Abstracts of papers given at the symposium are presented. Session topics include: Rydbergs, optical radiators, and planetary atoms; highly ionized atoms; ultraviolet radiation; theory, ion traps, and laser cooling; beam foil; and astronomy. (GHT)

  13. atomic fermi gas: Topics by E-print Network

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

    atomic Fermi gases. G. M. Bruun 2002-10-29 4 Fermi excitations in a trapped atomic Fermi gas with a molecular Bose condensate Condensed Matter (arXiv) Summary: We discuss the...

  14. Atom chip apparatus for experiments with ultracold rubidium and potassium gases

    SciTech Connect (OSTI)

    Ivory, M. K.; Ziltz, A. R.; Fancher, C. T.; Pyle, A. J.; Sensharma, A.; Chase, B.; Field, J. P.; Garcia, A.; Aubin, S., E-mail: saaubi@wm.edu [Department of Physics, College of William and Mary, Williamsburg, Virginia 23187 (United States); Jervis, D. [Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7 (Canada)] [Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7 (Canada)

    2014-04-15T23:59:59.000Z

    We present a dual chamber atom chip apparatus for generating ultracold {sup 87}Rb and {sup 39}K atomic gases. The apparatus produces quasi-pure Bose-Einstein condensates of 10{sup 4} {sup 87}Rb atoms in an atom chip trap that features a dimple and good optical access. We have also demonstrated production of ultracold {sup 39}K and subsequent loading into the chip trap. We describe the details of the dual chamber vacuum system, the cooling lasers, the magnetic trap, the multicoil magnetic transport system, the atom chip, and two optical dipole traps. Due in part to the use of light-induced atom desorption, the laser cooling chamber features a sufficiently good vacuum to also support optical dipole trap-based experiments. The apparatus is well suited for studies of atom-surface forces, quantum pumping and transport experiments, atom interferometry, novel chip-based traps, and studies of one-dimensional many-body systems.

  15. An ultra-bright atom laser

    E-Print Network [OSTI]

    V. Bolpasi; N. K. Efremidis; M. J. Morrissey; P. Condylis; D. Sahagun; M. Baker; W. von Klitzing

    2013-11-25T23:59:59.000Z

    We present a novel, ultra-bright atom-laser and ultra-cold thermal atom beam. Using rf-radiation we strongly couple the magnetic hyperfine levels of 87Rb atoms in a magnetically trapped Bose-Einstein condensate. At low rf-frequencies gravity opens a small hole in the trapping potenital and a well collimated, extremely bright atom laser emerges from just below the condensate. As opposed to traditional atom lasers based on weak coupling, this technique allows us to outcouple atoms at an arbitrarily large rate. We demonstrate an increase in flux per atom in the BEC by a factor of sixteen compared to the brightest quasi-continuous atom laser. Furthermore, we produce by two orders of magnitude the coldest thermal atom beam to date (200 nK).

  16. 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 31.6 s ± 3.4 s 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.

  17. 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.

  18. 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.

  19. Uncertainty Measurement for Trace Element Analysis of Uranium and Plutonium Samples by Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS)

    SciTech Connect (OSTI)

    Gallimore, David L. [Los Alamos National Laboratory

    2012-06-13T23:59:59.000Z

    The measurement uncertainty estimatino associated with trace element analysis of impurities in U and Pu was evaluated using the Guide to the Expression of Uncertainty Measurement (GUM). I this evalution the uncertainty sources were identified and standard uncertainties for the components were categorized as either Type A or B. The combined standard uncertainty was calculated and a coverage factor k = 2 was applied to obtain the expanded uncertainty, U. The ICP-AES and ICP-MS methods used were deveoped for the multi-element analysis of U and Pu samples. A typical analytical run consists of standards, process blanks, samples, matrix spiked samples, post digestion spiked samples and independent calibration verification standards. The uncertainty estimation was performed on U and Pu samples that have been analyzed previously as part of the U and Pu Sample Exchange Programs. Control chart results and data from the U and Pu metal exchange programs were combined with the GUM into a concentration dependent estimate of the expanded uncertainty. Comparison of trace element uncertainties obtained using this model was compared to those obtained for trace element results as part of the Exchange programs. This process was completed for all trace elements that were determined to be above the detection limit for the U and Pu samples.

  20. 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).

  1. 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.

  2. 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.

  3. Quantum information processing with trapped electrons and superconducting electronics

    E-Print Network [OSTI]

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

    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.

  4. Recent Progress in ultracold atoms

    E-Print Network [OSTI]

    Baltisberger, Jay H.

    , cold gas experiments 2. How to make a BEC out of fermions 3. Recent Progress: Controlling Interaction (Feshbach Resonance) 4. From BCS to BEC: Rotating trap and spin- polarized condensates. 5. Future research and Einstein What is Bose-Einstein condensation (BEC)? #12;300 K to 1 mK 109 atoms 1 mK to 1 mK 108 106 atoms

  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. 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.

  8. 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.

  9. 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.

  10. atomic bose-einstein condensate: Topics by E-print Network

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

    by periodically replenishing a condensate held in an optical dipole trap with new condensates delivered using optical tweezers. The source contained more than 1 106 atoms at all...

  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. 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.

  13. Nano Positioning of Single Atoms in a Micro Cavity

    E-Print Network [OSTI]

    Stefan Nussmann; Markus Hijlkema; Bernhard Weber; Felix Rohde; Gerhard Rempe; Axel Kuhn

    2005-06-10T23:59:59.000Z

    The coupling of individual atoms to a high-finesse optical cavity is precisely controlled and adjusted using a standing-wave dipole-force trap, a challenge for strong atom-cavity coupling. Ultracold Rubidium atoms are first loaded into potential minima of the dipole trap in the center of the cavity. Then we use the trap as a conveyor belt that we set into motion perpendicular to the cavity axis. This allows us to repetitively move atoms out of and back into the cavity mode with a repositioning precision of 135 nm. This makes possible to either selectively address one atom of a string of atoms by the cavity, or to simultaneously couple two precisely separated atoms to a higher mode of the cavity.

  14. 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 ...

  15. 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

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

    E-Print Network [OSTI]

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

    2010-09-15T23:59:59.000Z

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

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. atomic ions: Topics by E-print Network

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

    Lothar Ratschbacher; Carlo Sias; Michael Khl 2010-08-17 4 Micromotion in trapped atom-ion systems Quantum Physics (arXiv) Summary: We examine the validity of the harmonic...

  2. Towards a quantum gas microscope for fermionic atoms

    E-Print Network [OSTI]

    Ramasesh, Vinay (Vinay V.)

    2012-01-01T23:59:59.000Z

    This thesis reports the achievement of a two-species apparatus for use in an upcoming experiment with fermionic ultracold atomic gases. First, we describe the construction of a laser system capable of cooling and trapping ...

  3. atomic interaction networks: Topics by E-print Network

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

    or lambda configuration E. S. Guerra; C. R. Carvalho 2005-01-15 13 Trapped atomic condensates with anisotropic interactions Quantum Physics (arXiv) Summary: We study the ground...

  4. atomic oxygen interactions: Topics by E-print Network

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

    or lambda configuration E. S. Guerra; C. R. Carvalho 2005-01-15 16 Trapped atomic condensates with anisotropic interactions Quantum Physics (arXiv) Summary: We study the ground...

  5. atomic oxygen interaction: Topics by E-print Network

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

    or lambda configuration E. S. Guerra; C. R. Carvalho 2005-01-15 16 Trapped atomic condensates with anisotropic interactions Quantum Physics (arXiv) Summary: We study the ground...

  6. Realization of Bose-Einstein condensation with Lithium-7 atoms

    E-Print Network [OSTI]

    Yu, Yichao

    2014-01-01T23:59:59.000Z

    This thesis presents our work on developing and improving the techniques of trapping and cooling an ultra-cold cloud of Lithium-7 atoms and the realization of the Bose- Einstein condensate as a first step to study quantum ...

  7. 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.

  8. 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.

  9. 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.

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

    E-Print Network [OSTI]

    Torii, Yoshio

    Long storage time of collective coherence in an optically trapped Bose-Einstein condensate Yutaka of the storage time realized by loading the atoms into an optical dipole trap, wherein an unfavorable spin-dependent phase shift and spatial diffusion of atoms can be suppressed. The measured storage time was 0.57 2 ms

  11. Bose-Einstein condensation in dilute atomic gases1 Hans-Joachim Miesner and Wolfgang Ketterle

    E-Print Network [OSTI]

    -8] contained a more complete account on the cooling and trapping techniques and described the progress during and observe nanokelvin samples of atoms. Keywords: Bose-Einstein condensation, optical cooling and trapping atoms by two to three orders of magnitude. The observation of BEC in such systems [1-3] has created

  12. Probabilistic quantum gates between remote atoms through interference of optical frequency qubits

    E-Print Network [OSTI]

    Madsen, Martin John

    Probabilistic quantum gates between remote atoms through interference of optical frequency qubits L gates on remote trapped atom qubits through interference of optical frequency qubits. The method does be localized well under the Lamb-Dicke limit through laser cooling in a strong trap, the elimination

  13. Remote preparation of an atomic quantum memory

    E-Print Network [OSTI]

    Wenjamin Rosenfeld; Stefan Berner; Juergen Volz; Markus Weber; Harald Weinfurter

    2006-08-29T23:59:59.000Z

    Storage and distribution of quantum information are key elements of quantum information processing and quantum communication. Here, using atom-photon entanglement as the main physical resource, we experimentally demonstrate the preparation of a distant atomic quantum memory. Applying a quantum teleportation protocol on a locally prepared state of a photonic qubit, we realized this so-called remote state preparation on a single, optically trapped 87Rb atom. We evaluated the performance of this scheme by the full tomography of the prepared atomic state, reaching an average fidelity of 82%.

  14. 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.

  15. Design of a dual species atom interferometer for space

    E-Print Network [OSTI]

    Schuldt, Thilo; Krutzik, Markus; Bote, Lluis Gesa; Gaaloul, Naceur; Hartwig, Jonas; Ahlers, Holger; Herr, Waldemar; Posso-Trujillo, Katerine; Rudolph, Jan; Seidel, Stephan; Wendrich, Thijs; Ertmer, Wolfgang; Herrmann, Sven; Kubelka-Lange, André; Milke, Alexander; Rievers, Benny; Rocco, Emanuele; Hinton, Andrew; Bongs, Kai; Oswald, Markus; Franz, Matthias; Hauth, Matthias; Peters, Achim; Bawamia, Ahmad; Wicht, Andreas; Battelier, Baptiste; Bertoldi, Andrea; Bouyer, Philippe; Landragin, Arnaud; Massonnet, Didier; Lévèque, Thomas; Wenzlawski, Andre; Hellmig, Ortwin; Windpassinger, Patrick; Sengstock, Klaus; von Klitzing, Wolf; Chaloner, Chris; Summers, David; Ireland, Philip; Mateos, Ignacio; Sopuerta, Carlos F; Sorrentino, Fiodor; Tino, Guglielmo M; Williams, Michael; Trenkel, Christian; Gerardi, Domenico; Chwalla, Michael; Burkhardt, Johannes; Johann, Ulrich; Heske, Astrid; Wille, Eric; Gehler, Martin; Cacciapuoti, Luigi; Gürlebeck, Norman; Braxmaier, Claus; Rasel, Ernst

    2014-01-01T23:59:59.000Z

    Atom interferometers have a multitude of proposed applications in space including precise measurements of the Earth's gravitational field, in navigation & ranging, and in fundamental physics such as tests of the weak equivalence principle (WEP) and gravitational wave detection. While atom interferometers are realized routinely in ground-based laboratories, current efforts aim at the development of a space compatible design optimized with respect to dimensions, weight, power consumption, mechanical robustness and radiation hardness. In this paper, we present a design of a high-sensitivity differential dual species $^{85}$Rb/$^{87}$Rb atom interferometer for space, including physics package, laser system, electronics and software. The physics package comprises the atom source consisting of dispensers and a 2D magneto-optical trap (MOT), the science chamber with a 3D-MOT, a magnetic trap based on an atom chip and an optical dipole trap (ODT) used for Bose-Einstein condensate (BEC) creation and interferometry...

  16. 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.

  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. Laser cooling of two trapped ions: Sideband cooling beyond the Lamb-Dicke limit G. Morigi,1

    E-Print Network [OSTI]

    Blatt, Rainer

    of ultracold atoms, have provided renewed interest and applications for laser cooling techniques 1- onstrated to be a successful technique for cooling single ions to the ground state of a harmonic trap 9Laser cooling of two trapped ions: Sideband cooling beyond the Lamb-Dicke limit G. Morigi,1 J

  19. 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.

  20. 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.

  1. 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.

  2. Optical quantum swapping in a coherent atomic medium

    E-Print Network [OSTI]

    Aurelien Dantan

    2011-10-03T23:59:59.000Z

    We propose to realize a passive optical quantum swapping device which allows for the exchange of the quantum fluctuations of two bright optical fields interacting with a coherent atomic medium in an optical cavity. The device is based on a quantum interference process between the fields within the cavity bandwidth arising from coherent population trapping in the atomic medium.

  3. Mobile and remote inertial sensing with atom interferometers

    E-Print Network [OSTI]

    Boyer, Edmond

    Mobile and remote inertial sensing with atom interferometers B. Barrett, P.-A. Gominet, E. Cantin for equivalence principle tests. We also discuss fu- ture applications of this technology, such as remote sensing on laser-cooling and trapping neutral atoms [6, 7, 8, 9, 10] which eventually led to two nobel prizes

  4. 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.

  5. 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 ...

  6. 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.

  7. Loading atom lasers by collectivity-enhanced optical pumping

    SciTech Connect (OSTI)

    Macovei, Mihai A.; Evers, Joerg [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany)

    2010-01-15T23:59:59.000Z

    The effect of collectivity on the loading of an atom laser via optical pumping is discussed. In our model, atoms in a beam are laser-excited and subsequently spontaneously decay into a trapping state. We consider the case of sufficiently high particle density in the beam such that the spontaneous emission is modified by the particle interaction. We show that the collective effects lead to a better population of the trapping state over a wide range of system parameters, and that the second-order correlation function of the atoms can be controlled by the applied laser field.

  8. Trace metal mapping by laser-induced breakdown spectroscopy

    SciTech Connect (OSTI)

    Kaiser, Jozef [ORNL; Novotny, Dr. Karel [Masaryk University; Hrdlicka, A [Brno University of Technology, Czech Republic; Malina, R [Brno University of Technology, Czech Republic; Hartl, M [Brno University of Technology, Czech Republic; Kizek, R [Mendel University of Brno; Adam, V [Mendel University of Brno

    2012-01-01T23:59:59.000Z

    Abstract: Laser-Induced Breakdown Spectroscopy (LIBS) is a sensitive optical technique capable of fast multi-elemental analysis of solid, gaseous and liquid samples. The potential applications of lasers for spectrochemical analysis were developed shortly after its invention; however the massive development of LIBS is connected with the availability of powerful pulsed laser sources. Since the late 80s of 20th century LIBS dominated the analytical atomic spectroscopy scene and its application are developed continuously. Here we review the utilization of LIBS for trace elements mapping in different matrices. The main emphasis is on trace metal mapping in biological samples.

  9. Atom-Probe Tomographic Measurement of Trapped Hydrogen Isotopes |

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 1112011AT&T, Inc.'s ReplyApplication of Training AprilUnion Call to Make America

  10. Atom-Probe Tomographic Measurement of Trapped Hydrogen Isotopes |

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 111 1,613Portsmouth SitePresentationsMarketing CorporationTechnical ConferenceDepartment of

  11. Fundamental Electroweak Studies using Trapped Ions & Atoms

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.Newof Energy ForrestalPrincetonF2:Bioenergy SHARE

  12. Steven Chu: Laser Cooling and Trapping of Atoms

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del Sol HomeFacebookScholarshipSpiraling LaserAppropriationsLabAll of us

  13. 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...

  14. 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.

  15. Universal 1+2-body bound states in planar atomic wave guides Ludovic Pricoupenko(1)

    E-Print Network [OSTI]

    physics open the possi- bility of trapping and cooling atomic mixtures composed of different atomic species [1­4] in quasi two-dimensional (quasi-2D) geometries [5, 6]. These dramatic progress open exciting ratio. Motivated by these recent progress, we consider in this paper mixtures of two atomic species

  16. 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.

  17. 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.

  18. 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.

  19. 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...

  20. Studies of atomic hydrogen beam sources

    E-Print Network [OSTI]

    Schafer, Todd William

    1989-01-01T23:59:59.000Z

    with the Penning ion trap and data acquisition system, and to Mr. Shigu Tu for assisting him with the RF ion trap system and collection of data. TABLE OF CONTENTS CHAPTER Page I INTRODUCTION II BACKGROUND . II. 1 Atomic Hydrogen Production II. 2 Polarized..., and hexapole magnet present. However, testing was done on the Penning system with both discharge tubes. Atomrc hydrogen was produced in the source system by a rf discharge (30 MHz g: 73 MHz for the new and old discharge tubes, respectively) through a pyrex...

  1. Sensitivity of ultracold atoms to quantized flux in a superconducting ring

    E-Print Network [OSTI]

    Weiss, P; Bernon, S; Bothner, D; Sárkány, L; Zimmermann, C; Kleiner, R; Koelle, D; Fortágh, J; Hattermann, H

    2015-01-01T23:59:59.000Z

    We report on the magnetic trapping of an ultracold ensemble of $^{87}$Rb atoms close to a superconducting ring prepared in different states of quantized magnetic flux. The niobium ring of 10 $\\mu$m radius is prepared in a flux state $n \\Phi_0$, with $\\Phi_0 = h / 2e$ the flux quantum and $n$ varies between $\\pm 5$. An atomic cloud of 250 nK temperature is positioned with a harmonic magnetic trapping potential at $\\sim 18 \\mu$m distance below the ring. The inhomogeneous magnetic field of the supercurrent in the ring contributes to the magnetic trapping potential of the cloud. The induced deformation of the magnetic trap impacts the shape of the cloud, the number of trapped atoms as well as the center-of-mass oscillation frequency of Bose-Einstein condensates. When the field applied during cooldown of the chip is varied, the change of these properties shows discrete steps that quantitatively match flux quantization.

  2. 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.

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

    E-Print Network [OSTI]

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

    2014-11-22T23:59:59.000Z

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

  4. Heat-Traced Fluid Transfer Lines

    E-Print Network [OSTI]

    Schilling, R. E.

    1984-01-01T23:59:59.000Z

    HEAT-TRACED FLUID TRANSFER LINES Robert E. Schilling, P.E. Eaton Corporation Aurora, Ohio This paper discusses basic considerations in designing a heat tracing system using either steam or electrical tracing. Four basic reasons to heat...

  5. Coherence and Raman Sideband Cooling of a Single Atom in an Optical Tweezer

    E-Print Network [OSTI]

    Thompson, J. D.

    We investigate quantum control of a single atom in a tightly focused optical tweezer trap. We show that inevitable spatially varying polarization gives rise to significant internal-state decoherence but that this effect ...

  6. Multichannel calculations for frequency shift and line broadening cross sections in collisions of cold hydrogen atoms

    E-Print Network [OSTI]

    Zygelman, B.; Jamieson, M.J.

    Zygelman,B. Jamieson,M.J. Stancil,P.C. Dalgarno,A. Workshop on Collisions of Cold Trapped Atoms at Joint Institute for Laboratory Astrophysics, Boulder, CO, U.S.A.

  7. Tracing Geothermal Fluids

    SciTech Connect (OSTI)

    Michael C. Adams; Greg Nash

    2004-03-01T23:59:59.000Z

    Geothermal water must be injected back into the reservoir after it has been used for power production. Injection is critical in maximizing the power production and lifetime of the reservoir. To use injectate effectively the direction and velocity of the injected water must be known or inferred. This information can be obtained by using chemical tracers to track the subsurface flow paths of the injected fluid. Tracers are chemical compounds that are added to the water as it is injected back into the reservoir. The hot production water is monitored for the presence of this tracer using the most sensitive analytic methods that are economically feasible. The amount and concentration pattern of the tracer revealed by this monitoring can be used to evaluate how effective the injection strategy is. However, the tracers must have properties that suite the environment that they will be used in. This requires careful consideration and testing of the tracer properties. In previous and parallel investigations we have developed tracers that are suitable from tracing liquid water. In this investigation, we developed tracers that can be used for steam and mixed water/steam environments. This work will improve the efficiency of injection management in geothermal fields, lowering the cost of energy production and increasing the power output of these systems.

  8. Optimal trajectories for efficient atomic transport without final excitation

    E-Print Network [OSTI]

    Xi Chen; E. Torrontegui; Dionisis Stefanatos; Jr-Shin Li; J. G. Muga

    2011-08-08T23:59:59.000Z

    We design optimal harmonic-trap trajectories to transport cold atoms without final excitation, combining an inverse engineering techniqe based on Lewis-Riesenfeld invariants with optimal control theory. Since actual traps are not really harmonic, we keep the relative displacement between the center of mass and the trap center bounded. Under this constraint, optimal protocols are found according to different physical criteria. The minimum time solution has a "bang-bang" form, and the minimum displacement solution is of "bang-off-bang" form. The optimal trajectories for minimizing the transient energy are also discussed.

  9. Natural orbitals and Bose-Einstein condensates in traps: A diffusion Monte Carlo analysis J. L. DuBois and H. R. Glyde

    E-Print Network [OSTI]

    Glyde, Henry R.

    Natural orbitals and Bose-Einstein condensates in traps: A diffusion Monte Carlo analysis J. L. Du of the atoms in an ideal Bose gas can condense into a single quantum state. London 3,4 postulated in harmonic traps over a wide range of densities. Bose- Einstein condensation is formulated using the one

  10. 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.

  11. Epidemic Contact Tracing via Communication Traces Katayoun Farrahi1

    E-Print Network [OSTI]

    interactions, where contagious outbreaks propagate. However, due to privacy constraints and noisy data traces may be a viable option to arrest contagious outbreaks. Citation: Farrahi K, Emonet R, Cebrian M

  12. Atom Interferometry

    ScienceCinema (OSTI)

    Mark Kasevich

    2010-01-08T23:59:59.000Z

    Atom de Broglie wave interferometry has emerged as a tool capable of addressing a diverse set of questions in gravitational and condensed matter physics, and as an enabling technology for advanced sensors in geodesy and navigation. This talk will review basic principles, then discuss recent applications and future directions. Scientific applications to be discussed include measurement of G (Newton?s constant), tests of the Equivalence Principle and post-Newtonian gravity, and study of the Kosterlitz-Thouless phase transition in layered superfluids. Technology applications include development of precision gryoscopes and gravity gradiometers. The talk will conclude with speculative remarks looking to the future: Can atom interference methods be sued to detect gravity waves? Can non-classical (entangled/squeezed state) atom sources lead to meaningful sensor performance improvements?

  13. Adsorptive Stripping Voltammetric Measurements of Trace Uranium...

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

    Adsorptive Stripping Voltammetric Measurements of Trace Uranium at the Bismuth Film Electrode. Adsorptive Stripping Voltammetric Measurements of Trace Uranium at the Bismuth Film...

  14. Driven Ratchets for Cold Atoms

    E-Print Network [OSTI]

    Renzoni, F

    2011-01-01T23:59:59.000Z

    Brownian motors, or ratchets, are devices which "rectify" Brownian motion, i.e. they can generate a current of particles out of unbiased fluctuations. The ratchet effect is a very general phenomenon which applies to a wide range of physical systems, and indeed ratchets have been realized with a variety of solid state devices, with optical trap setups as well as with synthetic molecules and granular gases. The present article reviews recent experimental realizations of ac driven ratchets with cold atoms in driven optical lattices. This is quite an unusual system for a Brownian motor as there is no a real thermal bath, and both the periodic potential for the atoms and the fluctuations are determined by laser fields. Such a system allowed us to realize experimentally rocking and gating ratchets, and to precisely investigate the relationship between symmetry and transport in these ratchets, both for the case of periodic and quasiperiodic driving.

  15. Driven Ratchets for Cold Atoms

    E-Print Network [OSTI]

    F. Renzoni

    2011-12-05T23:59:59.000Z

    Brownian motors, or ratchets, are devices which "rectify" Brownian motion, i.e. they can generate a current of particles out of unbiased fluctuations. The ratchet effect is a very general phenomenon which applies to a wide range of physical systems, and indeed ratchets have been realized with a variety of solid state devices, with optical trap setups as well as with synthetic molecules and granular gases. The present article reviews recent experimental realizations of ac driven ratchets with cold atoms in driven optical lattices. This is quite an unusual system for a Brownian motor as there is no a real thermal bath, and both the periodic potential for the atoms and the fluctuations are determined by laser fields. Such a system allowed us to realize experimentally rocking and gating ratchets, and to precisely investigate the relationship between symmetry and transport in these ratchets, both for the case of periodic and quasiperiodic driving.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. Cold atoms as a coolant for levitated optomechanical systems

    E-Print Network [OSTI]

    Gambhir Ranjit; Cris Montoya; Andrew A. Geraci

    2014-12-17T23:59:59.000Z

    Optically trapped dielectric objects are well suited for reaching the quantum regime of their center of mass motion in an ultra-high vacuum environment. We show that ground state cooling of an optically trapped nanosphere is achievable when starting at room temperature, by sympathetic cooling of a cold atomic gas optically coupled to the nanoparticle. Unlike cavity cooling in the resolved sideband limit, this system requires only a modest cavity finesse and it allows the cooling to be turned off, permitting subsequent observation of strongly-coupled dynamics between the atoms and sphere. Nanospheres cooled to their quantum ground state could have applications in quantum information science or in precision sensing.

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

    E-Print Network [OSTI]

    Adams, James B

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

  2. Ion transport in macroscopic RF linear traps Jofre Pedregosa-Gutierrez,

    E-Print Network [OSTI]

    Boyer, Edmond

    ´er^ome, 13397 Marseille Cedex 20, France (Dated: July 18, 2014) Abstract Efficient transport of cold atomsIon transport in macroscopic RF linear traps Jofre Pedregosa-Gutierrez, Caroline Champenois, Marius information processing to frequency metrology. Different transport schemes have been developed, which allow

  3. Remote generation of entanglement for individual atoms via optical fibers

    E-Print Network [OSTI]

    Y. Q. Guo; H. Y. Zhong; Y. H. Zhang; H. S. Song

    2008-05-29T23:59:59.000Z

    The generation of atomic entanglement is discussed in a system that atoms are trapped in separate cavities which are connected via optical fibers. Two distant atoms can be projected to Bell-state by synchronized turning off the local laser fields and then performing a single quantum measurement by a distant controller. The distinct advantage of this scheme is that it works in a regime that $\\Delta\\approx\\kappa\\gg g$, which makes the scheme insensitive to cavity strong leakage. Moreover, the fidelity is not affected by atomic spontaneous emission.

  4. Magnetic-film atom chip with 10 $?$m period lattices of microtraps for quantum information science with Rydberg atoms

    E-Print Network [OSTI]

    V. Y. F. Leung; D. R. M. Pijn; H. Schlatter; L. Torralbo-Campo; A. La Rooij; G. B. Mulder; J. Naber; M. L. Soudijn; A. Tauschinsky; C. Abarbanel; B. Hadad; E. Golan; R. Folman; R. J. C. Spreeuw

    2014-07-01T23:59:59.000Z

    We describe the fabrication and construction of a setup for creating lattices of magnetic microtraps for ultracold atoms on an atom chip. The lattice is defined by lithographic patterning of a permanent magnetic film. Patterned magnetic-film atom chips enable a large variety of trapping geometries over a wide range of length scales. We demonstrate an atom chip with a lattice constant of 10 $\\mu$m, suitable for experiments in quantum information science employing the interaction between atoms in highly-excited Rydberg energy levels. The active trapping region contains lattice regions with square and hexagonal symmetry, with the two regions joined at an interface. A structure of macroscopic wires, cut out of a silver foil, was mounted under the atom chip in order to load ultracold $^{87}$Rb atoms into the microtraps. We demonstrate loading of atoms into the square and hexagonal lattice sections simultaneously and show resolved imaging of individual lattice sites. Magnetic-film lattices on atom chips provide a versatile platform for experiments with ultracold atoms, in particular for quantum information science and quantum simulation.

  5. Magnetic-film atom chip with 10 ?m period lattices of microtraps for quantum information science with Rydberg atoms

    SciTech Connect (OSTI)

    Leung, V. Y. F. [Van der Waals-Zeeman Institute, University of Amsterdam, Science Park 904, PO Box 94485, 1090 GL Amsterdam (Netherlands) [Van der Waals-Zeeman Institute, University of Amsterdam, Science Park 904, PO Box 94485, 1090 GL Amsterdam (Netherlands); Complex Photonic Systems (COPS), MESA Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede (Netherlands); Pijn, D. R. M.; Schlatter, H.; Torralbo-Campo, L.; La Rooij, A. L.; Mulder, G. B.; Naber, J.; Soudijn, M. L.; Tauschinsky, A.; Spreeuw, R. J. C., E-mail: r.j.c.spreeuw@uva.nl [Van der Waals-Zeeman Institute, University of Amsterdam, Science Park 904, PO Box 94485, 1090 GL Amsterdam (Netherlands)] [Van der Waals-Zeeman Institute, University of Amsterdam, Science Park 904, PO Box 94485, 1090 GL Amsterdam (Netherlands); Abarbanel, C.; Hadad, B.; Golan, E. [Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Be'er Sheva 84105 (Israel)] [Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Be'er Sheva 84105 (Israel); Folman, R. [Department of Physics and Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Be'er Sheva 84105 (Israel)] [Department of Physics and Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Be'er Sheva 84105 (Israel)

    2014-05-15T23:59:59.000Z

    We describe the fabrication and construction of a setup for creating lattices of magnetic microtraps for ultracold atoms on an atom chip. The lattice is defined by lithographic patterning of a permanent magnetic film. Patterned magnetic-film atom chips enable a large variety of trapping geometries over a wide range of length scales. We demonstrate an atom chip with a lattice constant of 10 ?m, suitable for experiments in quantum information science employing the interaction between atoms in highly excited Rydberg energy levels. The active trapping region contains lattice regions with square and hexagonal symmetry, with the two regions joined at an interface. A structure of macroscopic wires, cutout of a silver foil, was mounted under the atom chip in order to load ultracold {sup 87}Rb atoms into the microtraps. We demonstrate loading of atoms into the square and hexagonal lattice sections simultaneously and show resolved imaging of individual lattice sites. Magnetic-film lattices on atom chips provide a versatile platform for experiments with ultracold atoms, in particular for quantum information science and quantum simulation.

  6. Buffer-gas cooling of ions in a multipole radio frequency trap beyond the critical mass ratio

    E-Print Network [OSTI]

    Weckesser, P; López-Carrera, H; Weidemüller, M

    2015-01-01T23:59:59.000Z

    We theoretically investigate the dynamics of a trapped ion immersed in a spatially localized buffer gas. For a homogeneous buffer gas, the ion reaches a stable equilibrium only if the mass ratio of the buffer gas atom to the ion is below a critical value. We show how this limitation can be overcome by using multipole traps and a spatially confined buffer gas. Using a generalized model for elastic collisions of the ion with the buffer gas atoms, the ion's energy distribution is derived for arbitrary buffer gas distributions and trap parameters. Three regimes characterized by the analytical form of the ion's energy distribution are found. Final ion temperatures down to the millikelvin regime can be achieved even for heavy buffer gases by actively controlling the size of the buffer gas or the trap voltage (forced sympathetic cooling).

  7. Feedback Cooling of a Single Neutral Atom

    E-Print Network [OSTI]

    Markus Koch; Christian Sames; Alexander Kubanek; Matthias Apel; Maximilian Balbach; Alexei Ourjoumtsev; Pepijn W. H. Pinkse; Gerhard Rempe

    2010-10-15T23:59:59.000Z

    We demonstrate feedback cooling of the motion of a single rubidium atom trapped in a high-finesse optical resonator to a temperature of about 160 \\mu K. Time-dependent transmission and intensity-correlation measurements prove the reduction of the atomic position uncertainty. The feedback increases the 1/e storage time into the one second regime, 30 times longer than without feedback. Feedback cooling therefore rivals state-of-the-art laser cooling, but with the advantages that it requires less optical access and exhibits less optical pumping.

  8. Moller Polarimetry with Atomic Hydrogen Targets

    SciTech Connect (OSTI)

    Chudakov, Eugene [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Luppov, V. [University of Michigan Spin Physics Center, Ann Arbor, MI (United States)

    2012-06-01T23:59:59.000Z

    A proposal to use polarized atomic hydrogen gas as the target for electron beam polarimetry based on the Moller scattering is described. Such a gas, stored in an ultra-cold magnetic trap, would provide a target of practically 100\\% polarized electrons. It is conceivable to reach a $\\sim$0.3\\% systematic accuracy of the beam polarimetry with such a target. Feasibility studies for the CEBAF electron beam have been performed.

  9. ccsd-00001508,version1-1May2004 Realization of a magnetically guided atomic beam in the collisional regime

    E-Print Network [OSTI]

    Boyer, Edmond

    to periodically re- plenish with new condensates a gas sample held in an optical dipole trap. The second-Einstein condensation (BEC) [2] and pulsed "atom lasers" extracted from the condensate [3]. These advances in atom atom laser"). The first possibility [4] consists in using the "standard" condensation procedure

  10. Sub-Poissonian atom number fluctuations using light-assisted collisions

    E-Print Network [OSTI]

    Y. R. P. Sortais; A. Fuhrmanek; R. Bourgain; A. Browaeys

    2012-01-23T23:59:59.000Z

    We investigate experimentally the number statistics of a mesoscopic ensemble of cold atoms in a microscopic dipole trap loaded from a magneto-optical trap, and find that the atom number fluctuations are reduced with respect to a Poisson distribution due to light-assisted two-body collisions. For numbers of atoms N>2, we measure a reduction factor (Fano factor) of 0.72+/-0.07, which differs from 1 by more than 4 standard deviations. We analyze this fact by a general stochastic model describing the competition between the loading of the trap from a reservoir of cold atoms and multi-atom losses, which leads to a master equation. Applied to our experimental regime, this model indicates an asymptotic value of 3/4 for the Fano factor at large N and in steady state. We thus show that we have reached the ultimate level of reduction in number fluctuations in our system.

  11. 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

  12. Atom interferometry with Bose-Einstein condensates in a double-well The applicability, accuracy, and sensitivity of atom interferometers may be improved

    E-Print Network [OSTI]

    Atom interferometry with Bose-Einstein condensates in a double-well potential The applicability properties of gaseous Bose-Einstein condensates in combination with the fine manipulation capabilities created a trapped-atom interferometer using gaseous Bose-Einstein condensates coherently split

  13. Measuring Atomic Properties with an Atom Interferometer

    E-Print Network [OSTI]

    Roberts, Tony David

    2006-06-28T23:59:59.000Z

    Two experiments are presented which measure atomic properties using an atom interferometer. The interferometer splits the sodium de Broglie wave into two paths,

  14. Phase-space properties of magneto-optical traps utilising micro-fabricated gratings

    E-Print Network [OSTI]

    McGilligan, James P; Riis, Erling; Arnold, Aidan S

    2015-01-01T23:59:59.000Z

    We have used diffraction gratings to simplify the fabrication, and dramatically increase the atomic collection efficiency, of magneto-optical traps using micro-fabricated optics. The atom number enhancement was mainly due to the increased beam capture volume, afforded by the large area (4cm^2) shallow etch (200nm) binary grating chips. Here we provide a detailed theoretical and experimental investigation of the on-chip magneto-optical trap temperature and density in four different chip geometries using 87Rb, whilst studying effects due to MOT radiation pressure imbalance. With optimal initial MOTs on two of the chips we obtain both large atom number (2x10^7) _and_ sub-Doppler temperatures (50uK) after optical molasses.

  15. Long Range Interactions With Laser Cooled Neutral Atoms

    SciTech Connect (OSTI)

    Gattobigio, Giovanni Luca [Institut Non Lineaire de Nice, Universite de Nice-Sophia-Antipolis, CNRS UMR 661, 1361, route des Lucioles 06560 Valbonne France (France); Dipartimento di Fisica dell'Universita di Ferrara, 44100 Ferrara (Italy); Michaud, Franck; Labeyrie, Guillaume; Kaiser, Robin [Institut Non Lineaire de Nice, Universite de Nice-Sophia-Antipolis, CNRS UMR 661, 1361, route des Lucioles 06560 Valbonne (France); Loureiro, Jorge; Mendonca, Jose Tito; Tercas, Hugo [Instituto Superior Tecnico, Av. Rovisco Pais 1, 1049-001 Lisboa (Portugal); Pohl, Thomas [ITAMP, 60 Garden Street, Cambridge, MA 02138 (United States)

    2008-09-07T23:59:59.000Z

    Multiple scattering of light in a trap of laser cooled neutral atoms leads to repulsion forces between the atoms. The corresponding interactions have long range behavior in 1/r{sup 2} and are thus similar to Coulomb interaction in an one component confined plasma. Consequences of these interactions will be described in this paper, including the limitation of the spatial density one can obtain in such systems and self-sustained oscillations of the cloud.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. Sensitivity test of a blue-detuned dipole trap designed for parity non-conservation measurements in Fr

    E-Print Network [OSTI]

    Dong Sheng; Jiehang Zhang; Luis A. Orozco

    2012-04-23T23:59:59.000Z

    A dynamic blue-detuned optical dipole trap with stable $^{87}Rb$ atoms produces a differential ac Stark shift of 18 Hz in the ground state hyperfine transition, and it preserves the ground state hyperfine superpositions for a long coherence time of 180 ms. The trapped atoms undergoing microwave Rabi oscillations are sensitive to a small signal, artificially generated with a second microwave source, phase locked to the first allow- ing a simple and effective method for determining signal-to-noise ratio limits through interference techniques. This provides an excellent means of calibrating sensitivity in experiments such as our ongoing Fr parity non-conservation measurement.

  1. Phenomena of spin rotation and oscillation of particles (atoms, molecules) containing in a trap blowing on by wind of high energy particles in storage ring - new method of measuring of spin-dependent part of zero-angle coherent scattering amplitude

    E-Print Network [OSTI]

    Vladimir Baryshevsky

    2002-12-09T23:59:59.000Z

    New experiment arrangement to study spin rotation and oscillation of particles of gas target through which beam of high energy particles passes is discussed. Such experiment arrangement make it realizable for storage ring and allows to study zero-angle scattering amplitude at highest possible energies. Life-time of particle beam in storage ring can reach several hours and even days. Life-time of particle in gas target (gas trap) is long too. Particles circulate in storage ring with frequency $\

  2. 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-Püschel; 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.

  3. Atomic magnetometer

    DOE Patents [OSTI]

    Schwindt, Peter (Albuquerque, NM); Johnson, Cort N. (Albuquerque, NM)

    2012-07-03T23:59:59.000Z

    An atomic magnetometer is disclosed which uses a pump light beam at a D1 or D2 transition of an alkali metal vapor to magnetically polarize the vapor in a heated cell, and a probe light beam at a different D2 or D1 transition to sense the magnetic field via a polarization rotation of the probe light beam. The pump and probe light beams are both directed along substantially the same optical path through an optical waveplate and through the heated cell to an optical filter which blocks the pump light beam while transmitting the probe light beam to one or more photodetectors which generate electrical signals to sense the magnetic field. The optical waveplate functions as a quarter waveplate to circularly polarize the pump light beam, and as a half waveplate to maintain the probe light beam linearly polarized.

  4. Atom interferometry in an optical cavity

    E-Print Network [OSTI]

    Paul Hamilton; Matt Jaffe; Justin M. Brown; Lothar Maisenbacher; Brian Estey; Holger Müller

    2014-09-25T23:59:59.000Z

    We propose and demonstrate a new scheme for atom interferometry, using light pulses inside an optical cavity as matter wave beamsplitters. The cavity provides power enhancement, spatial filtering, and a precise beam geometry, enabling new techniques such as low power beamsplitters ($modest power, or new self-aligned interferometer geometries utilizing the transverse modes of the optical cavity. As a first demonstration, we obtain Ramsey-Raman fringes with $>75\\%$ contrast and measure the acceleration due to gravity, $\\mathit{g}$, to $60 \\mathrm{\\mu \\mathit{g} / \\sqrt{Hz}}$ resolution in a Mach-Zehnder geometry. We use $>10^7$ cesium atoms in the compact mode volume ($600 \\mathrm{\\mu m}$ $1/e^2$ waist) of the cavity and show trapping of atoms in higher transverse modes. This work paves the way toward compact, high sensitivity, multi-axis interferometry.

  5. Quantum Control of Qubits and Atomic Motion Using Ultrafast Laser Pulses

    E-Print Network [OSTI]

    J. Mizrahi; B. Neyenhuis; K. Johnson; W. C. Campbell; C. Senko; D. Hayes; C. Monroe

    2013-07-01T23:59:59.000Z

    Pulsed lasers offer significant advantages over CW lasers in the coherent control of qubits. Here we review the theoretical and experimental aspects of controlling the internal and external states of individual trapped atoms with pulse trains. Two distinct regimes of laser intensity are identified. When the pulses are sufficiently weak that the Rabi frequency $\\Omega$ is much smaller than the trap frequency $\\otrap$, sideband transitions can be addressed and atom-atom entanglement can be accomplished in much the same way as with CW lasers. By contrast, if the pulses are very strong ($\\Omega \\gg \\otrap$), impulsive spin-dependent kicks can be combined to create entangling gates which are much faster than a trap period. These fast entangling gates should work outside of the Lamb-Dicke regime and be insensitive to thermal atomic motion.

  6. Distributed trace using central performance counter memory

    DOE Patents [OSTI]

    Satterfield, David L; Sexton, James C

    2013-10-22T23:59:59.000Z

    A plurality of processing cores, are central storage unit having at least memory connected in a daisy chain manner, forming a daisy chain ring layout on an integrated chip. At least one of the plurality of processing cores places trace data on the daisy chain connection for transmitting the trace data to the central storage unit, and the central storage unit detects the trace data and stores the trace data in the memory co-located in with the central storage unit.

  7. Distributed trace using central performance counter memory

    DOE Patents [OSTI]

    Satterfield, David L.; Sexton, James C.

    2013-01-22T23:59:59.000Z

    A plurality of processing cores, are central storage unit having at least memory connected in a daisy chain manner, forming a daisy chain ring layout on an integrated chip. At least one of the plurality of processing cores places trace data on the daisy chain connection for transmitting the trace data to the central storage unit, and the central storage unit detects the trace data and stores the trace data in the memory co-located in with the central storage unit.

  8. LEARNING FROM BULLYING TRACES IN SOCIAL MEDIA

    E-Print Network [OSTI]

    Zhu, Xiaojin "Jerry"

    of bullying traces collected Lady Gaga Movie: Bully #12;Questions NLP Can Help with 8 Is the post a bullying

  9. angstrom noble gas: Topics by E-print Network

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

    (AMS) and Atom Trap Trace Analysis (ATTA). Collon, P; Lu, Z T 2004-01-01 5 Tracing Noble Gas Radionuclides in the Environment Nuclear Experiment (arXiv) Summary: Trace analysis of...

  10. 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

  11. 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

  12. Project AIRSTREAM: Trace gas final report

    SciTech Connect (OSTI)

    Leifer, R.

    1992-12-01T23:59:59.000Z

    The results of 10 years of sampling for trace gases in the upper troposphere and lower stratosphere are presented. These samples were collected under the auspices of the Atomic Energy Commission (AEC), the Energy Research and Development Administration (ERDA) and the Department of Energy (DOE). Almost 1000 whole air samples were collected during the years 1973 to 1983 under Project AIRSTREAM. Project AIRSTREAM was part of the Environmental Measurements Laboratory's (EML, at that time called the Health and Safety Laboratory/HASL) research effort to investigate the impact of the injection of radionuclides and stable compounds into the stratosphere. One or more of the following compounds were analyzed: CCl[sub 3]F, CCl[sub 2]F[sub 2], CCl[sub 4], N[sub 2]O, SF[sub 6], CO[sub 2], CH[sub 4], CH[sub 3]CCl[sub 3], and COS. Details of the Project's quality assurance program are discussed. Also included in the report are two-dimensional plots of the concentration of CCl[sub 3]F and a complete tabulation of the data.

  13. Project AIRSTREAM: Trace gas final report

    SciTech Connect (OSTI)

    Leifer, R.

    1992-12-01T23:59:59.000Z

    The results of 10 years of sampling for trace gases in the upper troposphere and lower stratosphere are presented. These samples were collected under the auspices of the Atomic Energy Commission (AEC), the Energy Research and Development Administration (ERDA) and the Department of Energy (DOE). Almost 1000 whole air samples were collected during the years 1973 to 1983 under Project AIRSTREAM. Project AIRSTREAM was part of the Environmental Measurements Laboratory`s (EML, at that time called the Health and Safety Laboratory/HASL) research effort to investigate the impact of the injection of radionuclides and stable compounds into the stratosphere. One or more of the following compounds were analyzed: CCl{sub 3}F, CCl{sub 2}F{sub 2}, CCl{sub 4}, N{sub 2}O, SF{sub 6}, CO{sub 2}, CH{sub 4}, CH{sub 3}CCl{sub 3}, and COS. Details of the Project`s quality assurance program are discussed. Also included in the report are two-dimensional plots of the concentration of CCl{sub 3}F and a complete tabulation of the data.

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

    SciTech Connect (OSTI)

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

    2012-02-28T23:59:59.000Z

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

  15. Casimir Effect and Trace formula Andreas Wirzba

    E-Print Network [OSTI]

    Wirzba, Andreas - Helmholtz-Institut für Strahlen- und Kernphysik (HISKP)

    1 Casimir Effect and Trace formula Andreas Wirzba Institut f¨ur Kernphysik Forschungszentrum J¨ulich · · Andreas Wirzba Casimir effect and trace formula Copenhagen, 17 May 2006 #12;1 Casimir Effect and Trace formula Andreas Wirzba Institut f¨ur Kernphysik Forschungszentrum J¨ulich 1. Introduction to the Casimir

  16. 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.

  17. Simplified motional heating rate measurements of trapped ions R. J. Epstein,* S. Seidelin, D. Leibfried, J. H. Wesenberg, J. J. Bollinger, J. M. Amini, R. B. Blakestad, J. Britton,

    E-Print Network [OSTI]

    Simplified motional heating rate measurements of trapped ions R. J. Epstein,* S. Seidelin, D. Leibfried, J. H. Wesenberg, J. J. Bollinger, J. M. Amini, R. B. Blakestad, J. Britton, J. P. Home, W. M have measured motional heating rates of trapped atomic ions, a factor that can influence multi

  18. Trace Explosive Detection Using Nanosensors

    SciTech Connect (OSTI)

    Senesac, Larry R [ORNL; Thundat, Thomas George [ORNL

    2008-01-01T23:59:59.000Z

    Selective and sensitive detection of explosives is very important in countering terrorist threats. Detecting trace explosives has become a very complex and expensive endeavor because of a number of factors, such as the wide variety of materials that can be used as explosives, the lack of easily detectable signatures, the vast number of avenues by which these weapons can be deployed, and the lack of inexpensive sensors with high sensitivity and selectivity. High sensitivity and selectivity, combined with the ability to lower the deployment cost of sensors using mass production, is essential in winning the war on explosives-based terrorism. Nanosensors have the potential to satisfy all the requirements for an effective platform for the trace detection of explosives.

  19. A ray tracing investigation of light trapping due to grooves in solar cells

    E-Print Network [OSTI]

    Ruggiero, Christopher W

    2007-01-01T23:59:59.000Z

    The biggest problem the world faces today is finding a renewable energy source as fossil fuel reserves being depleted, and the ongoing burning of fossil fuels is destroying environments all over the world. Solar energy is ...

  20. 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.

  1. Ultracold atoms in a cavity mediated double-well system

    E-Print Network [OSTI]

    Jonas Larson; Jani-Petri Martikainen

    2010-09-13T23:59:59.000Z

    We study ground-state properties and dynamics of a dilute ultracold atomic gas in a double well potential. The Gaussian barrier separating the two wells derives from the interaction between the atoms and a quantized field of a driven Fabry-Perot cavity. Due to intrinsic atom-field nonlinearity, several novel phenomena arise being the focus of this work. For the ground state, there is a critical pumping amplitude in which the atoms self-organize and the intra cavity field amplitude drastically increases. In the dynamical analysis, we show that the Josephson oscillations depend strongly on the atomic density and may be greatly suppressed within certain regimes, reminiscent of self-trapping of Bose-Einstein condensates in double-well setups. This pseudo self-trapping effect is studied within a mean-field treatment valid for large atom numbers. For small numbers of atoms, we consider the analogous many-body problem and demonstrate a collapse-revival structure in the Josephson oscillations.

  2. arXiv:0708.4197v1[cond-mat.other]30Aug2007 Optimal transport of ultracold atoms in the non-adiabatic regime

    E-Print Network [OSTI]

    Guéry-Odelin, David

    with ultracold atoms by moving slowly optical tweezers [3]. Transport of cold packets of atoms is also addressed numer- ically for ions in Paul traps [14]. In this article, we re- port on the transport of a coldarXiv:0708.4197v1[cond-mat.other]30Aug2007 Optimal transport of ultracold atoms in the non

  3. Atomism and Quantization Research Group in Mathematical Physics 1

    E-Print Network [OSTI]

    appear in two Laws of Nature: (i) Newton's Law of Universal Gravitation F(r) = - Gm 1 m 2 r 3 r , (1) where G is Newton's gravitational constant, and (ii) Planck's Law for the spectral energy density the gravitational interactions of matter. Traces of Atomism and of the three revolutions just described miraculously

  4. 2D Magneto-Optical Trapping of Diatomic Molecules Matthew T. Hummon,* Mark Yeo, Benjamin K. Stuhl,

    E-Print Network [OSTI]

    . Buffer gas cooling [14] and molecular beam slowing techniques, such as Stark [15] and Zeeman [16- and two-dimensional transverse laser cooling and magneto-optical trapping of the polar molecule yttrium precise control, produce new ultracold samples of atomic species not available with current cooling

  5. Long Range Interactions in MagnetoOptical Traps G. Labeyrie, G. L. Gattobigio, T. Pohl, and R. Kaiser

    E-Print Network [OSTI]

    .48.228.35. This article is copyrighted as indicated in the abstract. Reuse of AIP content is subject to the terms at: http is the dependence of the MOT size with number A^ of trapped atoms. We study in detail the scaling laws for the MOT and laser-cooled, yielding beautiful examples of crystallization due to the strong Coulomb interaction [4

  6. 526 OPTICS LETTERS / Vol. 17, No. 7 / April 1, 1992 Improved magneto-optic trapping in a vapor cell

    E-Print Network [OSTI]

    Gibble, Kurt

    to remain proportional to d4, the required laser power must in- crease as d3. Monroe et al.6 have shown-optic trap in a vapor cell and cap- turing atoms in the low-velocity tail of the thermal distribution distribution, which is proportional to v3 for v

  7. Three-wire magnetic trap for direct forced evaporative cooling Shengwang Du1,* and Eun Oh2

    E-Print Network [OSTI]

    Du, Shengwang

    Three-wire magnetic trap for direct forced evaporative cooling Shengwang Du1,* and Eun Oh2 1 Kong, China 2 U.S. Naval Research Laboratory, Remote Sensing Division, Washington, D.C. 20375, USA potential for direct forced evaporative cooling of neutral atoms without using induced spin

  8. Influence of monolayer contamination on electric-field-noise heating in ion traps

    E-Print Network [OSTI]

    A. Safavi-Naini; E. Kim; P. F. Weck; P. Rabl; H. R. Sadeghpour

    2012-09-28T23:59:59.000Z

    Electric field noise is a hinderance to the assembly of large scale quantum computers based on entangled trapped ions. Apart from ubiquitous technical noise sources, experimental studies of trapped ion heating have revealed additional limiting contributions to this noise, originating from atomic processes on the electrode surfaces. In a recent work [A. Safavi-Naini et al., Phys. Rev. A 84, 023412 (2011)] we described a microscopic model for this excess electric field noise, which points a way towards a more systematic understanding of surface adsorbates as progenitors of electric field jitter noise. Here, we address the impact of surface monolayer contamination on adsorbate induced noise processes. By using exact numerical calculations for H and N atomic monolayers on an Au(111) surface representing opposite extremes of physisorption and chemisorption, we show that an additional monolayer can significantly affect the noise power spectrum and either enhance or suppress the resulting heating rates.

  9. Laser cooling of trapped ions Jurgen Eschner

    E-Print Network [OSTI]

    Blatt, Rainer

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

  10. 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

  11. 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

  12. 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.

  13. Coherent cooling of atoms in a frequency-modulated standing laser wave: Wave function and stochastic trajectory approaches

    SciTech Connect (OSTI)

    Argonov, V. Yu., E-mail: argonov@poi.dvo.ru [Russian Academy of Sciences, Pacific Oceanological Institute (Russian Federation)

    2014-11-15T23:59:59.000Z

    The wave function of a moderately cold atom in a stationary near-resonant standing light wave delocalizes very fast due to wave packet splitting. However, we show that frequency modulation of the field can suppress packet splitting for some atoms whose specific velocities are in a narrow range. These atoms remain localized in a small space for a long time. We demonstrate and explain this effect numerically and analytically. We also demonstrate that the modulated field can not only trap but also cool the atoms. We perform a numerical experiment with a large atomic ensemble having wide initial velocity and energy distributions. During the experiment, most of atoms leave the wave while the trapped atoms have a narrow energy distribution.

  14. Chaotic Oscillations in Finite Quantum Systems: Trapped Bose-Einstein Condensates

    E-Print Network [OSTI]

    Luca Salasnich

    1999-06-22T23:59:59.000Z

    We discuss the recently achieved Bose-Einstein condensation for alkali-metal atoms in magnetic traps. The theoretically predicted low-energy collective oscillations of the condensate have been experimentally confirmed by laser imaging techniques. We show by using Poincar\\`e sections that at higher energies non-linear effects appear and oscillations become chaotic. PACS 03.75.Fi, 05.30.Jp, 05.45.+b, 32.80.Pj

  15. Electron shakeoff following the $\\Beta$+ decay of trapped 35Ar+ ions

    E-Print Network [OSTI]

    Couratin, C; Fabre, B; Pons, B; Fléchard, X; Liénard, E; Ban, G; Breitenfeldt, M; Delahaye, P; Durand, D; Méry, A; Naviliat-Cuncic, O; Porobic, T; Quéméner, G; Rodriguez, D; Severijns, N; Thomas, J C; Van Gorp, S

    2013-01-01T23:59:59.000Z

    The electron shakeoff of $^{35}$Cl atoms resulting from the $\\beta$$^+$ decay of $^{35}$Ar$^+$ ions has been investigated using a Paul trap coupled to a recoil-ion spectrometer. The charge-state distribution of the recoiling daughter nuclei is compared to theoretical calculations accounting for shakeoff and Auger processes. The calculations are in excellent agreement with the experimental results and enable to identify the ionization reaction routes leading to the formation of all charge states.

  16. 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 ¼ 26) to quantify catch at50 min, when the entry ratedeclined and the exit rate increased to a point where their confidence

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

    SciTech Connect (OSTI)

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

    2014-02-28T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Birgit Brandstätter; Andrew McClung; Klemens Schüppert; 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.

  19. Trace Holdings | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty Edit withTianlin Baxin Hydropower StationTown ofTown ofTown ofTrace Holdings Jump to:

  20. Stationary light in cold atomic gases

    E-Print Network [OSTI]

    Gor Nikoghosyan; Michael Fleischhauer

    2009-09-16T23:59:59.000Z

    We discuss stationary light created by a pair of counter-propagating control fields in Lambda-type atomic gases with electromagnetically induced transparency for the case of negligible Doppler broadening. In this case the secular approximation used in the discussion of stationary light in hot vapors is no longer valid. We discuss the quality of the effective light-trapping system and show that in contrast to previous claims it is finite even for vanishing ground-state dephasing. The dynamics of the photon loss is in general non exponential and can be faster or slower than in hot gases.

  1. 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...

  2. 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....

  3. 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 *...

  4. 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...

  5. 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...

  6. 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...

  7. Moøller polarimetry with polarized atomic hydrogen at MESA

    SciTech Connect (OSTI)

    Bartolomé, P. Aguar; Aulenbacher, K.; Tyukin, V. [Institut für Kernphysik, Johannes Gutenberg-University, D-55099 Mainz (Germany)

    2013-11-07T23:59:59.000Z

    A new generation of parity violation (PV) electron scattering experiments are planned to be carried out at the Institut für Kernphysik in Mainz. These experiments will be performed at low energies of 100-200 MeV using the new accelerator MESA (Mainz Energy recovering Superconducting Accelerator). One of the main challenges of such experiments is to achieve an accuracy in beam polarization measurements that must be below 0.5%. This very high accuracy can be reached using polarized atomic hydrogen gas, stored in an ultra-cold magnetic trap, as the target for electron beam polarimetry based on Mo/ller scattering. Electron spin-polarized atomic hydrogen can be stored at high densities of 10{sup 16} cm{sup ?2}, over relatively long time periods, in a high magnetic field (8T) and at low temperatures (0.3K). The gradient force splits the ground state of the hydrogen into four states with different energies. Atoms in the low energy states are trapped in the strong magnetic field region whereas the high energy states are repelled and pumped away. The physics of ultra-cold atomic hydrogen in magnetic traps and the status of the Mainz Hydro-Mo/ller project will be presented.

  8. Ultralong-Range Rydberg Molecules in a Divalent-Atomic System

    E-Print Network [OSTI]

    DeSalvo, B J; Dunning, F B; Killian, T C; Sadeghpour, H R; Yoshida, S; Burgdörfer, J

    2015-01-01T23:59:59.000Z

    We report the creation of ultralong-range Sr$_2$ molecules comprising one ground-state $5s^2$ $^1S_0$ atom and one atom in a $5sns$ $^3S_1$ Rydberg state for $n$ ranging from 29 to 36. Molecules are created in a trapped ultracold atomic gas using two-photon excitation near resonant with the $5s5p$ $^3P_1$ intermediate state, and their formation is detected through ground-state atom loss from the trap. The observed molecular binding energies are fit with the aid of first-order perturbation theory that utilizes a Fermi pseudopotential with effective $s$-wave and $p$-wave scattering lengths to describe the interaction between an excited Rydberg electron and a ground-state Sr atom.

  9. atom-atom collisions: Topics by E-print Network

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

    Atomic Safronova, Marianna 3 Atom-atom correlations in colliding Bose-Einstein condensates Quantum Physics (arXiv) Summary: We analyze atom-atom correlations in the s-wave...

  10. Radio-frequency dressed state potentials for neutral atoms

    E-Print Network [OSTI]

    S. Hofferberth; I. Lesanovsky; B. Fischer; J. Verdu; J. Schmiedmayer

    2006-08-29T23:59:59.000Z

    Potentials for atoms can be created by external fields acting on properties like magnetic moment, charge, polarizability, or by oscillating fields which couple internal states. The most prominent realization of the latter is the optical dipole potential formed by coupling ground and electronically excited states of an atom with light. Here we present an experimental investigation of the remarkable properties of potentials derived from radio-frequency (RF) coupling between electronic ground states. The coupling is magnetic and the vector character allows to design state dependent potential landscapes. On atom chips this enables robust coherent atom manipulation on much smaller spatial scales than possible with static fields alone. We find no additional heating or collisional loss up to densities approaching $10^{15}$ atoms / cm$^3$ compared to static magnetic traps. We demonstrate the creation of Bose-Einstein condensates in RF potentials and investigate the difference in the interference between two independently created and two coherently split condensates in identical traps. All together this makes RF dressing a powerful new tool for micro manipulation of atomic and molecular systems.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. Traces on Module Categories over Fusion Categories

    E-Print Network [OSTI]

    Gregor Schaumann

    2015-01-27T23:59:59.000Z

    We consider traces on module categories over pivotal fusion categories which are compatible with the module structure. It is shown that such module traces characterise the Morita classes of special haploid symmetric Frobenius algebras. Moreover, they are unique up to a scale factor and they equip the dual category with a pivotal structure. This implies that for each pivotal structure on a fusion category over the complex numbers there exists a conjugate pivotal structure defined by the canonical module trace.

  16. 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.

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

    E-Print Network [OSTI]

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

    2014-09-30T23:59:59.000Z

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

  18. 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.

  19. 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...

  20. Optimized coupling of cold atoms into a fiber using a blue-detuned hollow-beam funnel

    SciTech Connect (OSTI)

    Poulin, Jerome; Light, Philip S.; Kashyap, Raman; Luiten, Andre N. [Frequency Standards and Metrology Group, School of Physics, University of Western Australia, Western Australia 6009, Perth (Australia); Department of Engineering Physics, Ecole Polytechnique de Montreal, Montreal, Quebec, Canada H3C 3A7 (Canada); Frequency Standards and Metrology, School of Physics, University of Western Australia, Western Australia 6009, Perth (Australia)

    2011-11-15T23:59:59.000Z

    We theoretically investigate the process of coupling cold atoms into the core of a hollow-core photonic-crystal optical fiber using a blue-detuned Laguerre-Gaussian beam. In contrast to the use of a red-detuned Gaussian beam to couple the atoms, the blue-detuned hollow beam can confine cold atoms to the darkest regions of the beam, thereby minimizing shifts in the internal states and making the guide highly robust to heating effects. This single optical beam is used as both a funnel and a guide to maximize the number of atoms into the fiber. In the proposed experiment, Rb atoms are loaded into a magneto-optical trap (MOT) above a vertically oriented optical fiber. We observe a gravito-optical trapping effect for atoms with high orbital momentum around the trap axis, which prevents atoms from coupling to the fiber: these atoms lack the kinetic energy to escape the potential and are thus trapped in the laser funnel indefinitely. We find that by reducing the dipolar force to the point at which the trapping effect just vanishes, it is possible to optimize the coupling of atoms into the fiber. Our simulations predict that by using a low-power (2.5 mW) and far-detuned (300 GHz) Laguerre-Gaussian beam with a 20-{mu}m-radius core hollow fiber, it is possible to couple 11% of the atoms from a MOT 9 mm away from the fiber. When the MOT is positioned farther away, coupling efficiencies over 50% can be achieved with larger core fibers.

  1. 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...

  2. 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

  3. Stable heteronuclear few-atom bound states in mixed dimensions

    SciTech Connect (OSTI)

    Yin Tao; Zhang Peng; Zhang Wei [Department of Physics, Renmin University of China, Beijing 100872 (China)

    2011-11-15T23:59:59.000Z

    We study few-body problems in mixed dimensions where two or three heavy atoms are trapped individually in parallel one-dimensional tubes or two-dimensional disks and a single light atom travels freely in three dimensions. Using the Born-Oppenheimer approximation, we find three- and four-body bound states for a broad parameter region. Specifically, the existence of trimer and tetramer states persists to the negative scattering length regime, where no two-body bound state is present. As pointed out by Y. Nishida in an earlier work [Phys. Rev. A 82, 011605(R) (2010)], these few-body bound states are stable against three-body recombination due to geometric separation. In addition, we find that the binding energy of the ground trimer and tetramer state reaches its maximum value when the scattering lengths are comparable to the separation between the low-dimensional traps.

  4. Using a scalar parameter to trace dislocation evolution in atomistic modeling

    SciTech Connect (OSTI)

    Yang, Jinbo [ORNL; Zhang, Z F [Shenyang National Laboratory for Materials Science; Osetskiy, Yury N [ORNL; Stoller, Roger E [ORNL

    2015-01-01T23:59:59.000Z

    A scalar gamma-parameter is proposed from the Nye tensor. Its maximum value occurs along a dislocation line, either straight or curved, when the coordinate system is purposely chosen. This parameter can be easily obtained from the Nye tensor calculated at each atom in atomistic modeling. Using the gamma-parameter, a fully automated approach is developed to determine core atoms and the Burgers vectors of dislocations simultaneously. The approach is validated by revealing the smallest dislocation loop and by tracing the whole formation process of complicated dislocation networks on the fly.

  5. Entangling Atomic Spins with a Strong Rydberg-Dressed Interaction

    E-Print Network [OSTI]

    Jau, Y -Y; Keating, Tyler; Deutsch, I H; Biedermann, G W

    2015-01-01T23:59:59.000Z

    Controlling quantum entanglement between parts of a many-body system is the key to unlocking the power of quantum information processing for applications such as quantum computation, highprecision sensing, and simulation of many-body physics. Spin degrees of freedom of ultracold neutral atoms in their ground electronic state provide a natural platform given their long coherence times and our ability to control them with magneto-optical fields, but creating strong coherent coupling between spins has been challenging. We demonstrate a Rydberg-dressed ground-state blockade that provides a strong tunable interaction energy (~1 MHz in units of Planck's constant) between spins of individually trapped cesium atoms. With this interaction we directly produce Bell-state entanglement between two atoms with a fidelity >= 81(2)%, excluding atom loss events, and >= 60(3)% when loss is included.

  6. Probing the Kondo Lattice Model with Alkaline Earth Atoms

    E-Print Network [OSTI]

    Michael Foss-Feig; Michael Hermele; Ana Maria Rey

    2009-12-24T23:59:59.000Z

    We study transport properties of alkaline-earth atoms governed by the Kondo Lattice Hamiltonian plus a harmonic confining potential, and suggest simple dynamical probes of several different regimes of the phase diagram that can be implemented with current experimental techniques. In particular, we show how Kondo physics at strong coupling, low density, and in the heavy fermion phase is manifest in the dipole oscillations of the conduction band upon displacement of the trap center.

  7. Edge Transport in 2D Cold Atom Optical Lattices

    E-Print Network [OSTI]

    V. W. Scarola; S. Das Sarma

    2007-05-24T23:59:59.000Z

    We theoretically study the observable response of edge currents in two dimensional cold atom optical lattices. As an example we use Gutzwiller mean-field theory to relate persistent edge currents surrounding a Mott insulator in a slowly rotating trapped Bose-Hubbard system to time of flight measurements. We briefly discuss an application, the detection of Chern number using edge currents of a topologically ordered optical lattice insulator.

  8. Preparation of three-dimensional entanglement for distant atoms in coupled cavities via atomic spontaneous emission and cavity decay

    E-Print Network [OSTI]

    Shi-Lei Su; Xiao-Qiang Shao; Hong-Fu Wang; Shou Zhang

    2014-08-21T23:59:59.000Z

    We propose a dissipative scheme to prepare a three-dimensional entangled state for two atoms trapped in separate coupled cavities. Our work shows that both atomic spontaneous emission and cavity decay, which are two typical obstacles in unitary-dynamics-based schemes, could be utilized as resources for high-dimensional entangled state preparation without specifying initial state and controlling time precisely. Final numerical simulation with one group of experimental parameters indicates that the performance of our scheme is better than the unitary-dynamics-based scheme.

  9. Atomizing nozzle and process

    DOE Patents [OSTI]

    Anderson, I.E.; Figliola, R.S.; Molnar, H.M.

    1993-07-20T23:59:59.000Z

    High pressure atomizing nozzle includes a high pressure gas manifold having a divergent expansion chamber between a gas inlet and arcuate manifold segment to minimize standing shock wave patterns in the manifold and thereby improve filling of the manifold with high pressure gas for improved melt atomization. The atomizing nozzle is especially useful in atomizing rare earth-transition metal alloys to form fine powder particles wherein a majority of the powder particles exhibit particle sizes having near-optimum magnetic properties.

  10. Ultracold-atom collisions in atomic waveguides : A two-channel analysis

    E-Print Network [OSTI]

    Tom Kristensen; Ludovic Pricoupenko

    2015-04-16T23:59:59.000Z

    Low dimensional behavior of two ultra-cold atoms trapped in two-and one-dimensional waveguides is investigated in the vicinity of a magnetic Feshbach resonance. A quantitative two-channel model for the Feshbach mechanism is used allowing an exhaustive analysis of low-dimensional resonant scattering behavior and of the confinement induced bound states. The role of the different parameters of the resonance is depicted in this context. Results are compared with the ones of the zero-range approach. The relevance of the effective range approximation in low dimensions is studied. Examples of known resonances are used to illustrate the bound state properties.

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

    E-Print Network [OSTI]

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

    2015-04-06T23:59:59.000Z

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

  12. Atomic swelling upon compression

    E-Print Network [OSTI]

    V. K. Dolmatov; J. L. King

    2012-08-18T23:59:59.000Z

    The hydrogen atom under the pressure of a spherical penetrable confinement potential of a decreasing radius $r_{0}$ is explored, as a case study. A novel counter-intuitive effect of atomic swelling rather than shrinking with decreasing $r_{0}$ is unraveled, when $r_{0}$ reaches, and remains smaller than, a certain critical value. Upon swelling, the size of the atom is shown to increase by an order of magnitude, or more, compared to the size of the free atom. Examples of changes of photoabsorption properties of confined hydrogen atom upon its swelling are uncovered and demonstrated.

  13. Method for remote detection of trace contaminants

    DOE Patents [OSTI]

    Simonson, Robert J.; Hance, Bradley G.

    2003-09-09T23:59:59.000Z

    A method for remote detection of trace contaminants in a target area comprises applying sensor particles that preconcentrate the trace contaminant to the target area and detecting the contaminant-sensitive fluorescence from the sensor particles. The sensor particles can have contaminant-sensitive and contaminant-insensitive fluorescent compounds to enable the determination of the amount of trace contaminant present in the target are by relative comparison of the emission of the fluorescent compounds by a local or remote fluorescence detector. The method can be used to remotely detect buried minefields.

  14. Infrared near-field spectroscopy of trace explosives using an...

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

    spectroscopy of trace explosives using an external cavity quantum cascade laser. Infrared near-field spectroscopy of trace explosives using an external cavity quantum cascade...

  15. Workshop on L-functions and Trace Formula

    E-Print Network [OSTI]

    Ali Altug, Columbia University: Trace formula beyond endoscopy and analytic number theory. I will talk about trace formula and analytic number theory, and how ...

  16. Feasibility of the detection of trace elements in particulate...

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

    of trace elements in particulate matter using online High-Resolution Aerosol Mass Spectrometry. Feasibility of the detection of trace elements in particulate matter using online...

  17. Design of a dual species atom interferometer for space

    E-Print Network [OSTI]

    Thilo Schuldt; Christian Schubert; Markus Krutzik; Lluis Gesa Bote; Naceur Gaaloul; Jonas Hartwig; Holger Ahlers; Waldemar Herr; Katerine Posso-Trujillo; Jan Rudolph; Stephan Seidel; Thijs Wendrich; Wolfgang Ertmer; Sven Herrmann; André Kubelka-Lange; Alexander Milke; Benny Rievers; Emanuele Rocco; Andrew Hinton; Kai Bongs; Markus Oswald; Matthias Franz; Matthias Hauth; Achim Peters; Ahmad Bawamia; Andreas Wicht; Baptiste Battelier; Andrea Bertoldi; Philippe Bouyer; Arnaud Landragin; Didier Massonnet; Thomas Lévèque; Andre Wenzlawski; Ortwin Hellmig; Patrick Windpassinger; Klaus Sengstock; Wolf von Klitzing; Chris Chaloner; David Summers; Philip Ireland; Ignacio Mateos; Carlos F. Sopuerta; Fiodor Sorrentino; Guglielmo M. Tino; Michael Williams; Christian Trenkel; Domenico Gerardi; Michael Chwalla; Johannes Burkhardt; Ulrich Johann; Astrid Heske; Eric Wille; Martin Gehler; Luigi Cacciapuoti; Norman Gürlebeck; Claus Braxmaier; Ernst Rasel

    2014-12-08T23:59:59.000Z

    Atom interferometers have a multitude of proposed applications in space including precise measurements of the Earth's gravitational field, in navigation & ranging, and in fundamental physics such as tests of the weak equivalence principle (WEP) and gravitational wave detection. While atom interferometers are realized routinely in ground-based laboratories, current efforts aim at the development of a space compatible design optimized with respect to dimensions, weight, power consumption, mechanical robustness and radiation hardness. In this paper, we present a design of a high-sensitivity differential dual species $^{85}$Rb/$^{87}$Rb atom interferometer for space, including physics package, laser system, electronics and software. The physics package comprises the atom source consisting of dispensers and a 2D magneto-optical trap (MOT), the science chamber with a 3D-MOT, a magnetic trap based on an atom chip and an optical dipole trap (ODT) used for Bose-Einstein condensate (BEC) creation and interferometry, the detection unit, the vacuum system for $10^{-11}$ mbar ultra-high vacuum generation, and the high-suppression factor magnetic shielding as well as the thermal control system. The laser system is based on a hybrid approach using fiber-based telecom components and high-power laser diode technology and includes all laser sources for 2D-MOT, 3D-MOT, ODT, interferometry and detection. Manipulation and switching of the laser beams is carried out on an optical bench using Zerodur bonding technology. The instrument consists of 9 units with an overall mass of 221 kg, an average power consumption of 608 W (819 W peak), and a volume of 470 liters which would well fit on a satellite to be launched with a Soyuz rocket, as system studies have shown.

  18. 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.

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

    E-Print Network [OSTI]

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

    2011-09-15T23:59:59.000Z

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

  20. 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.

  1. 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.

  2. 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.

  3. Mass measurements near the $r$-process path using the Canadian Penning Trap mass spectrometer

    E-Print Network [OSTI]

    J. Van Schelt; D. Lascar; G. Savard; J. A. Clark; S. Caldwell; A. Chaudhuri; J. Fallis; J. P. Greene; A. F. Levand; G. Li; K. S. Sharma; M. G. Sternberg; T. Sun; B. J. Zabransky

    2012-04-09T23:59:59.000Z

    The masses of 40 neutron-rich nuclides from Z = 51 to 64 were measured at an average precision of $\\delta m/m= 10^{-7}$ using the Canadian Penning Trap mass spectrometer at Argonne National Laboratory. The measurements, of fission fragments from a $^{252}$Cf spontaneous fission source in a helium gas catcher, approach the predicted path of the astrophysical $r$ process. Where overlap exists, this data set is largely consistent with previous measurements from Penning traps, storage rings, and reaction energetics, but large systematic deviations are apparent in $\\beta$-endpoint measurements. Differences in mass excess from the 2003 Atomic Mass Evaluation of up to 400 keV are seen, as well as systematic disagreement with various mass models.

  4. 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.

  5. Privacy Vulnerability of Published Anonymous Mobility Traces

    E-Print Network [OSTI]

    2010-07-07T23:59:59.000Z

    Sep 20, 2010 ... locations of real users leading to the public availabilities of many such traces through .... infer the private information. ... are open to observations in public spaces. Hence, the ..... value is called the entropy rate of the process X.

  6. RESTRICTED-TRACE APPROXIMATION FOR NUCLEAR ANTIFERROMAGNETISM

    E-Print Network [OSTI]

    Boyer, Edmond

    1353 RESTRICTED-TRACE APPROXIMATION FOR NUCLEAR ANTIFERROMAGNETISM M. GOLDMAN and G. SARMA Service to predict several properties of nuclear antiferromagnetic structures : sublattice magnetization of nuclear dipolar magnetic ordering, either antiferromagnetic or ferromagnetic, has been reported

  7. Extraction of trace metals from fly ash

    DOE Patents [OSTI]

    Blander, Milton (Palos Park, IL); Wai, Chien M. (Moscow, ID); Nagy, Zoltan (Woodridge, IL)

    1984-01-01T23:59:59.000Z

    A process for recovering silver, gallium and/or other trace metals from a fine grained industrial fly ash associated with a process for producing phosphorous, the fly ash having a silicate base and containing surface deposits of the trace metals as oxides, chlorides or the like, with the process being carried out by contacting the fly ash with AlCl.sub.3 in an alkali halide melt to react the trace metals with the AlCl.sub.3 to form compositions soluble in the melt and a residue containing the silicate and aluminum oxide or other aluminum precipitate, and separating the desired trace metal or metals from the melt by electrolysis or other separation techniques.

  8. Extraction of trace metals from fly ash

    DOE Patents [OSTI]

    Blander, M.; Wai, C.M.; Nagy, Z.

    1983-08-15T23:59:59.000Z

    A process is described for recovering silver, gallium and/or other trace metals from a fine grained industrial fly ash associated with a process for producing phosphorous. The fly ash has a silicate base and contains surface deposits of the trace metals as oxides, chlorides or the like. The process is carried out by contacting the fly ash with AlCl/sub 3/ in an alkali halide melt to react the trace metals with the AlCl/sub 3/ to form compositions soluble in the melt and a residue containing the silicate and aluminum oxide or other aluminum precipitate, and separating the desired trace metal or metals from the melt by electrolysis or other separation techniques.

  9. 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.

  10. 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...

  11. 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.

  12. 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.

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

    SciTech Connect (OSTI)

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

    2014-10-15T23:59:59.000Z

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

  14. EBIT (Electron Beam Ion Trap), N-Division Experimental Physics. Annual report, 1994

    SciTech Connect (OSTI)

    Schneider, D. [ed.

    1995-10-01T23:59:59.000Z

    The experimental groups in the Electron Beam Ion Trap (EBIT) program continue to perform front-line research with trapped and extracted highly charged ions (HCI) in the areas of ion/surface interactions, atomic spectroscopy, electron-ion interaction and structure measurements, highly charged ion confinement, and EBIT development studies. The ion surface/interaction studies which were initiated five years ago have reached a stage where they an carry out routine investigations, as well as produce breakthrough results towards the development of novel nanotechnology. At EBIT and SuperEBIT studies of the x-ray emission from trapped ions continue to produce significant atomic structure data with high precision for few electron systems of high-Z ions. Furthermore, diagnostics development for magnetic and laser fusion, supporting research for the x-ray laser and weapons programs, and laboratory astrophysics experiments in support of NASA`s astrophysics program are a continuing effort. The two-electron contributions to the binding energy of helium like ions were measured for the first time. The results are significant because their precision is an order of magnitude better than those of competing measurements at accelerators, and the novel technique isolates the energy corrections that are the most interesting. The RETRAP project which was initiated three years ago has reached a stage where trapping, confining and electronic cooling of HCI ions up to Th{sup 80+} can be performed routinely. Measurements of the rates and cross sections for electron transfer from H{sub 2} performed to determine the lifetime of HCI up to Xe{sup q+} and Th{sup q+} (35 {le} q {le} 80) have been studied at mean energies estimated to be {approximately} 5 q eV. This combination of heavy ions with very high charges and very low energies is rare in nature, but may be encountered in planned fusion energy demonstration devices, in highly charged ion sources, or in certain astrophysical events.

  15. Trace element analysis of Texas lignite

    E-Print Network [OSTI]

    Mahar, Sean

    1982-01-01T23:59:59.000Z

    or in the planning stages, Near surface lignite re- sources are estimated to be 21 billion metric tons in Texas, while deep basin reserves are estimated at 31 billion metric tons. Near (3] surface reserves alone could fulfill Texas' electrical needs for 100 years... for environmental and health concerns trace element characterization of lignites is important. A needed avenue of research is charact- erization of trace element pathways in lignite fired power plants. :hat is to say what percentage of a certain element...

  16. Trapped ytterbium ions for scalable quantum Ion Quantum Technology Group, Department of Physics and Astronomy, University of Sussex, Brighton, East Sussex,

    E-Print Network [OSTI]

    Hensinger, Winfried

    performed accurate measurements of 2S1/2 2P1/2 and 2D3/2 3D[3/2]1/2 transitions for Yb+ isotopes. Motional to retain and control atoms during shuttling operations inside ion trap arrays. Vacuum system Vacuum chamber

  17. Bose-Einstein condensation in trapped bosons: A variational Monte Carlo analysis J. L. DuBois and H. R. Glyde

    E-Print Network [OSTI]

    Glyde, Henry R.

    Bose-Einstein condensation in trapped bosons: A variational Monte Carlo analysis J. L. DuBois and H describes the whole gas well. Effects of atoms excited above the condensate have been incorporated within correlations is used to study the sensitivity of condensate and noncondensate properties to the hard- sphere

  18. Capture Dynamics of Ultracold Atoms in the Presence of an Impurity Ion

    E-Print Network [OSTI]

    J. M. Schurer; A. Negretti; P. Schmelcher

    2015-05-01T23:59:59.000Z

    Following the sudden creation of a single ion in a quasi one-dimensional trapped ultracold ensemble of bosonic atoms, the major part of the atoms is captured in the vicinity of the ion, while the remaining fraction is emitted towards the outer regions of the trap. Subsequently, the two energy scales stemming from the trapping potential and the atom-ion interaction give rise to two major density oscillations. While the first one corresponds to a dipole oscillation, the second one results from a coherent superposition of an atom-ion bound and a trap state which causes spatial coherence and population transfer between the two density fractions. Induced by the dynamical build-up of correlations, this second oscillation exhibits a collapse and revival behavior. We apply the ab initio multiconfiguration time-dependent Hartree method for bosons to explore the nonequilibrium quantum dynamics and analyze it via a cluster expansion approach. The latter is adapted to bosonic systems of fixed particle number which provides us with a thorough understanding of the complicated many-body processes.

  19. Normal-Mode Spectroscopy of a Single-Bound-AtomCavity System P. Maunz, T. Puppe, I. Schuster, N. Syassen, P. W. H. Pinkse, and G. Rempe

    E-Print Network [OSTI]

    Rempe, Gerhard

    Normal-Mode Spectroscopy of a Single-Bound-Atom­Cavity System P. Maunz, T. Puppe, I. Schuster, N is stored in an intracavity dipole trap and cavity cooling is used to compensate for inevitable heating. Two Experimental research in quantum information science with atoms and ions [1] is based on the ability to control

  20. Optomechanical Rydberg-atom excitation via dynamic Casimir-Polder coupling

    E-Print Network [OSTI]

    Mauro Antezza; Caterina Braggio; Giovanni Carugno; Antonio Noto; Roberto Passante; Lucia Rizzuto; Giuseppe Ruoso; Salvatore Spagnolo

    2014-07-09T23:59:59.000Z

    We study the optomechanical coupling of a oscillating effective mirror with a Rydberg atomic gas, mediated by the dynamical atom-mirror Casimir-Polder force. This coupling may produce a near-field resonant atomic excitation whose probability scales as $\\propto (d^2\\;a\\;n^4\\;t)^2/z_0^8$, where $z_0$ is the average atom-surface distance, $d$ the atomic dipole moment, $a$ the mirror's effective oscillation amplitude, $n$ the initial principal quantum number, and $t$ the time. We propose an experimental configuration to realize this system with a cold atom gas trapped at a distance $\\sim 2\\cdot10 \\, \\mu$m from a semiconductor substrate, whose dielectric constant is periodically driven by an external laser pulse, hence realizing en effective mechanical mirror motion due to the periodic change of the substrate from transparent to reflecting. For a parabolic gas shape, this effect is predicted to excite about $\\sim 10^2$ atoms of a dilute gas of $10^3$ trapped Rydberg atoms with $n=75$ after about $0.5 \\,\\mu \\mbox{s}$, hence high enough to be detected in typical Rydberg gas experimental conditions.

  1. Quantum criticality and universal scaling of strongly attractive spin-imbalanced Fermi gases in a one-dimensional harmonic trap

    SciTech Connect (OSTI)

    Yin Xiangguo; Chen Shu [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Guan Xiwen [Department of Theoretical Physics, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia); Batchelor, Murray T. [Department of Theoretical Physics, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia); Mathematical Sciences Institute, Australian National University, Canberra ACT 0200 (Australia)

    2011-07-15T23:59:59.000Z

    We investigate quantum criticality and universal scaling of strongly attractive Fermi gases confined in a one-dimensional harmonic trap. We demonstrate from the power-law scaling of the thermodynamic properties that current experiments on this system are capable of measuring universal features at quantum criticality, such as universal scaling and Tomonaga-Luttinger liquid physics. The results also provide insights on recent measurements of key features of the phase diagram of a spin-imbalanced atomic Fermi gas [Y. Liao et al., Nature (London) 467, 567 (2010)] and point to further study of quantum critical phenomena in ultracold atomic Fermi gases.

  2. VOLUME 74, NUMBER 26 P H Y S I C A L R E V I E W L E T T E R S 26 JUNE 1995 Evaporative Cooling of Sodium Atoms

    E-Print Network [OSTI]

    which allow the cooling of atoms to temperatures below the recoil limit. Optical techniques and trap loss due to ex- cited state collisions [5]. The technique of forced evapora- tive cooling relies of different cooling and trapping techniques involving lasers and mag- netic fields we were able to obtain

  3. Improved graphite furnace atomizer

    DOE Patents [OSTI]

    Siemer, D.D.

    1983-05-18T23:59:59.000Z

    A graphite furnace atomizer for use in graphite furnace atomic absorption spectroscopy is described wherein the heating elements are affixed near the optical path and away from the point of sample deposition, so that when the sample is volatilized the spectroscopic temperature at the optical path is at least that of the volatilization temperature, whereby analyteconcomitant complex formation is advantageously reduced. The atomizer may be elongated along its axis to increase the distance between the optical path and the sample deposition point. Also, the atomizer may be elongated along the axis of the optical path, whereby its analytical sensitivity is greatly increased.

  4. Atomic Collapse Observed

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

    Scientists Observe Atomic Collapse State Quantum Mechanics Prediction Confirmed in Graphene Using NERSC's Hopper April 26, 2013 | Tags: Hopper, Materials Science Contact: Linda...

  5. 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 ...

  6. 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.

  7. 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 ...

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

    E-Print Network [OSTI]

    Boynton, T.; Dewhirst, B.

    1980-01-01T23:59:59.000Z

    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...

  9. 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...

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. 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

  15. The trace formula The Langevin process in R

    E-Print Network [OSTI]

    Herrmann, Samuel

    The trace formula The Langevin process in R Symmetric spaces and the Malliavin calculus and the trace formula Jean-Michel Bismut Universit´e Paris-Sud, Orsay `A la m´emoire de Paul Malliavin Jean-Michel Bismut The Malliavin calculus and the trace formula #12;The trace formula The Langevin process in R

  16. Measurement of low-energy Na^+ -- Na total collision rate in an ion--neutral hybrid trap

    E-Print Network [OSTI]

    Goodman, D S; Kwolek, J M; Blümel, R; Narducci, F A; Smith, W W

    2014-01-01T23:59:59.000Z

    We present measurements of the total elastic and resonant charge-exchange ion-atom collision rate coefficient $k_\\mathrm{ia}$ of cold sodium (\\ce{Na}) with optically-dark low energy \\ce{Na+} ions in a hybrid ion-neutral trap. To determine $k_\\mathrm{ia}$, we measured the trap loading and loss from both a \\ce{Na} magneto-optical trap (MOT) and a linear radio frequency quadrupole Paul trap. We found the total rate coefficient to be $7.4 \\pm 1.9 \\times 10^{-8}$ cm$^3$/s for the type I \\ce{Na} MOT immersed within an $\\approx 140$ K ion cloud and $1.10 \\pm 0.25 \\times 10^{-7}$ cm$^3$/s for the type II \\ce{Na} MOT within an $\\approx 1070$ K ion cloud. Our measurements show excellent agreement with previously reported theoretical fully quantal \\textit{ab initio} calculations. In the process of determining the total rate coefficient, we demonstrate that a MOT can be used to probe an optically dark ion cloud's spatial distribution within a hybrid trap.

  17. Topological Insulators and Metals in Atomic Optical Lattices

    E-Print Network [OSTI]

    Tudor D. Stanescu; Victor Galitski; J. Y. Vaishnav; Charles W. Clark; S. Das Sarma

    2009-01-26T23:59:59.000Z

    We propose the realization of topological quantum states with cold atoms trapped in an optical lattice. We discuss an experimental setup that generates a two-dimensional hexagonal lattice in the presence of a light-induced periodic vector potential, which represents a realization of the Haldane model with cold atoms. We determine theoretically the conditions necessary for observing the topological states and show that two of the key conditions are: 1) the realization of sharp boundaries and 2) the minimization of any smoothly varying component of the confining potential. We argue that, unlike their condensed matter counterparts, cold atom topological quantum states can be i) "seen", by mapping out the characteristic chiral edge states, and ii) controlled, by controlling the periodic vector potential and the properties of the confining potential.

  18. 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

  19. Observation of Nonlinear Self-Trapping of Broad Beams in Defocusing Waveguide Arrays

    SciTech Connect (OSTI)

    Bennet, Francis H.; Haslinger, Franz; Neshev, Dragomir N.; Kivshar, Yuri S. [Nonlinear Physics Centre, Centre for Ultrahigh-Bandwidth Devices for Optical Systems (CUDOS), Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200 (Australia); Alexander, Tristram J. [Nonlinear Physics Centre, Centre for Ultrahigh-Bandwidth Devices for Optical Systems (CUDOS), Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200 (Australia)] [School of Physical, Environmental and Mathematical Sciences, UNSW-ADFA, Canberra ACT 2600 (Australia); Mitchell, Arnan [CUDOS, School of Electrical and Computer Engineering, RMIT University, Melbourne Vic 3001 (Australia)

    2011-03-04T23:59:59.000Z

    We demonstrate experimentally the localization of broad optical beams in periodic arrays of optical waveguides with defocusing nonlinearity. This observation in optics is linked to nonlinear self-trapping of Bose-Einstein-condensed atoms in stationary periodic potentials being associated with the generation of truncated nonlinear Bloch states, existing in the gaps of the linear transmission spectrum. We reveal that unlike gap solitons, these novel localized states can have an arbitrary width defined solely by the size of the input beam while independent of nonlinearity.

  20. Trapping and transmission of matter-wave solitons in a collisionally inhomogeneous environment

    E-Print Network [OSTI]

    G. Theocharis; P. Schmelcher; P. G. Kevrekidis; D. J. Frantzeskakis

    2005-09-18T23:59:59.000Z

    We investigate bright matter-wave solitons in the presence of a spatially varying scattering length. It is demonstrated that, even in the absence of any external trapping potential, a soliton can be confined due to the inhomogeneous collisional interactions. Moreover we observe the enhanced transmission of matter-wave solitons through potential barriers for suitably chosen spatial variations of the scattering length. The results indicate that the manipulation of atomic interactions can become a versatile tool to control the dynamics of matter waves.

  1. 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

  2. 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.

  3. 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

  4. 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

  5. Alkali vapor pressure modulation on the 100 ms scale in a single-cell vacuum system for cold atom experiments

    SciTech Connect (OSTI)

    Dugrain, Vincent; Reichel, Jakob [Laboratoire Kastler Brossel, ENS, UPMC, CNRS, 24 rue Lhomond, 75005 Paris (France); Rosenbusch, Peter [LNE-SYRTE, Observatoire de Paris, CNRS, UPMC, 61 av de l’Observatoire, 75014 Paris (France)

    2014-08-15T23:59:59.000Z

    We describe and characterize a device for alkali vapor pressure modulation on the 100 ms timescale in a single-cell cold atom experiment. Its mechanism is based on optimized heat conduction between a current-modulated alkali dispenser and a heat sink at room temperature. We have studied both the short-term behavior during individual pulses and the long-term pressure evolution in the cell. The device combines fast trap loading and relatively long trap lifetime, enabling high repetition rates in a very simple setup. These features make it particularly suitable for portable atomic sensors.

  6. Cavity Nonlinear Optics at Low Photon Numbers from Collective Atomic Motion

    E-Print Network [OSTI]

    Subhadeep Gupta; Kevin L. Moore; Kater W. Murch; Dan M. Stamper-Kurn

    2007-09-05T23:59:59.000Z

    We report on Kerr nonlinearity and dispersive optical bistability of a Fabry-Perot optical resonator due to the displacement of ultracold atoms trapped within. In the driven resonator, such collective motion is induced by optical forces acting upon up to $10^5$ $^{87}$Rb atoms prepared in the lowest band of a one-dimensional intracavity optical lattice. The longevity of atomic motional coherence allows for strongly nonlinear optics at extremely low cavity photon numbers, as demonstrated by the observation of both branches of optical bistability at photon numbers below unity.

  7. Producing and Detecting Correlated atoms

    E-Print Network [OSTI]

    Christoph I. Westbrook; Martijn Schellekens; Aurélien Perrin; Valentina Krachmalnicoff; Jose Carlos Viana Gomes; Jean-Baptiste Trebbia; Jérôme Estève; Hong Chang; Isabelle Bouchoule; Denis Boiron; Alain Aspect; Tom Jeltes; John McNamara; Wim Hogervorst; Wim Vassen

    2006-09-04T23:59:59.000Z

    We discuss experiments to produce and detect atom correlations in a degenerate or nearly degenerate gas of neutral atoms. First we treat the atomic analog of the celebrated Hanbury Brown Twiss experiment, in which atom correlations result simply from interference effects without any atom interactions.We have performed this experiment for both bosons and fermions. Next we show how atom interactions produce correlated atoms using the atomic analog of spontaneous four-wavemixing. Finally, we briefly mention experiments on a one dimensional gas on an atom chip in which correlation effects due to both interference and interactions have been observed.

  8. A high-flux BEC source for mobile atom interferometers

    E-Print Network [OSTI]

    Jan Rudolph; Waldemar Herr; Christoph Grzeschik; Tammo Sternke; Alexander Grote; Manuel Popp; Dennis Becker; Hauke Müntinga; Holger Ahlers; Achim Peters; Claus Lämmerzahl; Klaus Sengstock; Naceur Gaaloul; Wolfgang Ertmer; Ernst M. Rasel

    2015-06-16T23:59:59.000Z

    Quantum sensors based on coherent matter-waves are precise measurement devices whose ultimate accuracy is achieved with Bose-Einstein condensates (BEC) in extended free fall. This is ideally realized in microgravity environments such as drop towers, ballistic rockets and space platforms. However, the transition from lab-based BEC machines to robust and mobile sources with comparable performance is a challenging endeavor. Here we report on the realization of a miniaturized setup, generating a flux of $4 \\times 10^5$ quantum degenerate $^{87}$Rb atoms every 1.6$\\,$s. Ensembles of $1 \\times 10^5$ atoms can be produced at a 1$\\,$Hz rate. This is achieved by loading a cold atomic beam directly into a multi-layer atom chip that is designed for efficient transfer from laser-cooled to magnetically trapped clouds. The attained flux of degenerate atoms is on par with current lab-based BEC experiments while offering significantly higher repetition rates. Additionally, the flux is approaching those of current interferometers employing Raman-type velocity selection of laser-cooled atoms. The compact and robust design allows for mobile operation in a variety of demanding environments and paves the way for transportable high-precision quantum sensors.

  9. Rapid chain tracing of polypeptide backbones in electron-density maps

    SciTech Connect (OSTI)

    Terwilliger, Thomas C., E-mail: terwilliger@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2010-03-01T23:59:59.000Z

    A method for rapid chain tracing of polypeptide backbones at moderate resolution is presented. A method for the rapid tracing of polypeptide backbones has been developed. The method creates an approximate chain tracing that is useful for visual evaluation of whether a structure has been solved and for use in scoring the quality of electron-density maps. The essence of the method is to (i) sample candidate C{sup ?} positions at spacings of approximately 0.6 Å along ridgelines of high electron density, (ii) list all possible nonapeptides that satisfy simple geometric and density criteria using these candidate C{sup ?} positions, (iii) score the nonapeptides and choose the highest scoring ones, and (iv) find the longest chains that can be made by connecting nonamers. An indexing and storage scheme that allows a single calculation of most distances and density values is used to speed up the process. The method was applied to 42 density-modified electron-density maps at resolutions from 1.5 to 3.8 Å. A total of 21 428 residues in these maps were traced in 24 CPU min with an overall r.m.s.d. of 1.61 Å for C{sup ?} atoms compared with the known refined structures. The method appears to be suitable for rapid evaluation of electron-density map quality.

  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. On-line Excited-State Laser Spectroscopy of Trapped Short-Lived Ra$^+$ Ions

    E-Print Network [OSTI]

    O. O. Versolato; G. S. Giri; L. W. Wansbeek; J. E. van den Berg; D. J. van der Hoek; K. Jungmann; W. L. Kruithof; C. J. G. Onderwater; B. K. Sahoo; B. Santra; P. D. Shidling; R. G. E. Timmermans; L. Willmann; H. W. Wilschut

    2010-03-29T23:59:59.000Z

    As an important step towards an atomic parity violation experiment in one single trapped Ra$^+$ ion, laser spectroscopy experiments were performed with on-line produced short-lived $^{212,213,214}$Ra$^+$ ions. The isotope shift of the $6\\,^2$D$_{3/2}$\\,-\\,$7\\,^2$P$_{1/2}$ and $6\\,^2$D$_{3/2}$\\,-\\,$7\\,^2$P$_{3/2}$ transitions and the hyperfine structure constant of the $7\\,^2$S$_{1/2}$ and $6\\,^2$D$_{3/2}$ states in $^{213}$Ra$^+$ were measured. These values provide a benchmark for the required atomic theory. A lower limit of $232(4)$ ms for the lifetime of the metastable $6\\,^2$D$_{5/2}$ state was measured by optical shelving.

  12. Tritium--helium-3 mass difference using the Penning trap mass spectroscopy

    SciTech Connect (OSTI)

    Van Dyck, R.S. Jr.; Farnham, D.L.; Schwinberg, P.B. (Department of Physics, FM-15, University of Washington, Seattle, Washington 98195 (United States))

    1993-05-10T23:59:59.000Z

    The atomic masses of both [sup 3]H and [sup 3]He have been measured with a Penning trap mass spectrometer that utilizes a frequency-shift detector to observe ion cyclotron resonances. Present resolution exceeds 1 part in 10[sup 9] and is limited only by the stability of the magnetic field. The leading systematic shift (at [approx lt]1 part in 10[sup 10]) is due to the residual quadratic [bold B] field dependence. The atomic masses have been combined to yield [Delta][ital Mc][sup 2]([sup 3]H[minus][sup 3]He)=18 590.1(1.7) eV. The excellent agreement with recent results from [beta] spectrometers lends strong support for new limits on the neutrino's rest mass.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. Trace fossil assemblages in selected shelf sandstones

    E-Print Network [OSTI]

    Locke, Kathleen Ann

    1983-01-01T23:59:59.000Z

    and decreasing marine 1nfluence. Individual trace fossil types are more abundant and show a greater d1versity 1n the delta-margin facies; several large, vert1cal crab(?) burrows are P ascot a d th bi g is do 1 t d by ~Ohio o h In the shelf sequences, mostly... ~Zoo h os, f d ly i th iddl -to. outer and outer shelf sequences. Continued study of trace fossils should provide more specific information than the general shelf locations described above. ACKNOWLEDGEMENTS The completion of this thesis marks...

  18. Trace element analysis of Texas lignite 

    E-Print Network [OSTI]

    Mahar, Sean

    1982-01-01T23:59:59.000Z

    . Gluskoter, and N. F. Shimp: Occurence and Distribution of Potentiall Volatile Trace Elements in Coal. Illinois State Geological Survey. Urbana, IL. (July, 1974). 39 [26] Andren, A. W. , D. H. Klein, and Y. Talmi: Selenium in Coal- Fired Plant Emissions.... Envir. Sci. and Tech. , 9:856, (Sept. , 1975). [27] Gluskoter, H. J. , R. R. Ruch, W. G. Miller, R. A. Cahill, G. B. Breher and J, K. Kuhn: Trace Elements in Coal: Occur- rence and Distribution. Illinois State Geological Sur- vey. Urbane, Illinois...

  19. Deeply-trapped molecules in self-nanostructured gas-phase material

    E-Print Network [OSTI]

    Alharbi, M; Debord, B; Gerome, F; Benabid, F

    2015-01-01T23:59:59.000Z

    Since the advent of atom laser-cooling, trapping or cooling natural molecules has been a long standing and challenging goal. Here, we demonstrate a method for laser-trapping molecules that is radically novel in its configuration, in its underlined physical dynamics and in its outcomes. It is based on self-optically spatially-nanostructured high pressure molecular hydrogen confined in hollow-core photonic-crystal-fibre. An accelerating molecular-lattice is formed by a periodic potential associated with Raman saturation except for a 1-dimentional array of nanometer wide and strongly-localizing sections. In these sections, molecules with a speed of as large as 1800 m/s are trapped, and stimulated Raman scattering in the Lamb-Dicke regime occurs to generate high power forward and backward-Stokes continuous-wave laser with sideband-resolved sub-Doppler emission spectrum. The spectrum exhibits a central line with a sub-recoil linewidth of as low as 14 kHz, more than 5 orders-of-magnitude narrower than in convention...

  20. Deeply-trapped molecules in self-nanostructured gas-phase material

    E-Print Network [OSTI]

    M. Alharbi; A. Husakou; B. Debord; F. Gerome; F. Benabid

    2015-06-03T23:59:59.000Z

    Since the advent of atom laser-cooling, trapping or cooling natural molecules has been a long standing and challenging goal. Here, we demonstrate a method for laser-trapping molecules that is radically novel in its configuration, in its underlined physical dynamics and in its outcomes. It is based on self-optically spatially-nanostructured high pressure molecular hydrogen confined in hollow-core photonic-crystal-fibre. An accelerating molecular-lattice is formed by a periodic potential associated with Raman saturation except for a 1-dimentional array of nanometer wide and strongly-localizing sections. In these sections, molecules with a speed of as large as 1800 m/s are trapped, and stimulated Raman scattering in the Lamb-Dicke regime occurs to generate high power forward and backward-Stokes continuous-wave laser with sideband-resolved sub-Doppler emission spectrum. The spectrum exhibits a central line with a sub-recoil linewidth of as low as 14 kHz, more than 5 orders-of-magnitude narrower than in conventional Raman scattering, and sidebands comprising Mollow triplet, molecular motional-sidebands and four-wave-mixing.

  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. 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...

  3. 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...

  4. Trace metal and ancillary data in the open waters of Puget Sound: 1980-1985. Data report

    SciTech Connect (OSTI)

    Paulson, A.J.; Curl, H.C.; Feely, R.A.; Geiselman, T.; Krogslund, K.A.

    1991-04-01T23:59:59.000Z

    In the second of three data reports, the complete data set between 1980 and 1985 for the open waters of Puget Sound is presented. The water column data are divided geographically. The information gained from these data has been interpreted by PMEL scientists and is published in a variety of scientific journals that are listed within each section. Building on research then underway at PMEL on estuarine circulation, laboratory scientists began a coordinated study that began with the description of the distribution of properties (salinity, temperature, trace metals and trace organics) in the water column and underlying sediments. The objectives of the Marine Environmental Quality trace metal program were (1) to quantify the sources and sinks of selected trace metals for Puget Sound, (2) to determine geochemical mechanisms that transform trace metals between the dissolved and particulate phases and (3) to determine to what extent these geochemical mechanisms alter the fate of trace metals entering Puget Sound. The water column data are divided geographically in the following manner: Duwamish River, Duwamish Waterway, Elliott Bay and Commencement Bay and other rivers discharging into Puget Sound. In addition to the water column data, sediment trap, sediment column solid phase and sediment column interstitial phase (pore water) data are presented. The text of the data report consists of the sampling and analytical methods with the accompanying quality control/quality assurance data. The text of the data sections are a summary of the data and published literature in which the data are interpreted along with a catalogue of the data available on microfiche located in the back pocket of the data report. In most cases, a table consists of one station with the parameters as columns and the depths as rows.

  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. Atomic and molecular supernovae

    SciTech Connect (OSTI)

    Liu, W.

    1997-12-01T23:59:59.000Z

    Atomic and molecular physics of supernovae is discussed with an emphasis on the importance of detailed treatments of the critical atomic and molecular processes with the best available atomic and molecular data. The observations of molecules in SN 1987A are interpreted through a combination of spectral and chemical modelings, leading to strong constraints on the mixing and nucleosynthesis of the supernova. The non-equilibrium chemistry is used to argue that carbon dust can form in the oxygen-rich clumps where the efficient molecular cooling makes the nucleation of dust grains possible. For Type Ia supernovae, the analyses of their nebular spectra lead to strong constraints on the supernova explosion models.

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

    SciTech Connect (OSTI)

    Scielzo, Nicholas David

    2003-06-01T23:59:59.000Z

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

  8. Trace metals in sediments of coastal Siberia 

    E-Print Network [OSTI]

    Esnough, Teresa Elizabeth

    1996-01-01T23:59:59.000Z

    For the work described in this thesis, a total of 218 samples from 104 cores from the East Siberian, Laptev, Kara, and Pechora Seas and the Ob and Yenisei Rivers were analyzed for the trace metals Ag, As, Ba, Cd, Cr, Cu, Fe, Hg, Ni, Pb, Sb, and Zn...

  9. Trace elements and Polycyclic Aromatic Hydrocarbons (PAHs)

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Trace elements and Polycyclic Aromatic Hydrocarbons (PAHs) in snow and ice sampled at Colle designed, built and tested. Melt water from inner part of ice core section was pumped to an ICP-SFMS and ICP-OES. Melt water from outer section was on-line extracted by solid-phase cartridges for semi

  10. Background Concentrations of Trace Metals in

    E-Print Network [OSTI]

    Ma, Lena

    of Florida State University System of Florida FLORIDA CENTER FOR SOLID AND HAZARDOUS WASTE MANAGEMENT 2207 NW for evaluating land application of non-hazardous waste materials and monitoring the mobility of trace metals from 8,000 archived samples. l To validate the sampling protocol used by the Florida Cooperative Soil

  11. Trace metals in sediments of coastal Siberia

    E-Print Network [OSTI]

    Esnough, Teresa Elizabeth

    1996-01-01T23:59:59.000Z

    For the work described in this thesis, a total of 218 samples from 104 cores from the East Siberian, Laptev, Kara, and Pechora Seas and the Ob and Yenisei Rivers were analyzed for the trace metals Ag, As, Ba, Cd, Cr, Cu, Fe, Hg, Ni, Pb, Sb, and Zn...

  12. Metal atomization spray nozzle

    DOE Patents [OSTI]

    Huxford, T.J.

    1993-11-16T23:59:59.000Z

    A spray nozzle for a magnetohydrodynamic atomization apparatus has a feed passage for molten metal and a pair of spray electrodes mounted in the feed passage. The electrodes, diverging surfaces which define a nozzle throat and diverge at an acute angle from the throat. Current passes through molten metal when fed through the throat which creates the Lorentz force necessary to provide atomization of the molten metal. 6 figures.

  13. Atomizing nozzle and method

    DOE Patents [OSTI]

    Ting, Jason (Ames, IA); Anderson, Iver E. (Ames, IA); Terpstra, Robert L. (Ames, IA)

    2000-03-16T23:59:59.000Z

    A high pressure close-coupled gas atomizing nozzle includes multiple discrete gas jet discharge orifices having aerodynamically designed convergent-divergent geometry with an first converging section communicated to a gas supply manifold and to a diverging section by a constricted throat section to increase atomizing gas velocity. The gas jet orifices are oriented at gas jet apex angle selected relative to the melt supply tip apex angle to establish a melt aspiration condition at the melt supply tip.

  14. Optical atomic magnetometer

    DOE Patents [OSTI]

    Budker, Dmitry; Higbie, James; Corsini, Eric P

    2013-11-19T23:59:59.000Z

    An optical atomic magnetometers is provided operating on the principles of nonlinear magneto-optical rotation. An atomic vapor is optically pumped using linearly polarized modulated light. The vapor is then probed using a non-modulated linearly polarized light beam. The resulting modulation in polarization angle of the probe light is detected and used in a feedback loop to induce self-oscillation at the resonant frequency.

  15. Atomic mass compilation 2012

    SciTech Connect (OSTI)

    Pfeiffer, B., E-mail: bpfeiffe@uni-mainz.de [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany); GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany); Venkataramaniah, K. [Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam (India)] [Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam (India); Czok, U. [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany)] [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany); Scheidenberger, C. [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany) [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany); II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany)

    2014-03-15T23:59:59.000Z

    Atomic mass reflects the total binding energy of all nucleons in an atomic nucleus. Compilations and evaluations of atomic masses and derived quantities, such as neutron or proton separation energies, are indispensable tools for research and applications. In the last decade, the field has evolved rapidly after the advent of new production and measuring techniques for stable and unstable nuclei resulting in substantial ameliorations concerning the body of data and their precision. Here, we present a compilation of atomic masses comprising the data from the evaluation of 2003 as well as the results of new measurements performed. The relevant literature in refereed journals and reports as far as available, was scanned for the period beginning 2003 up to and including April 2012. Overall, 5750 new data points have been collected. Recommended values for the relative atomic masses have been derived and a comparison with the 2003 Atomic Mass Evaluation has been performed. This work has been carried out in collaboration with and as a contribution to the European Nuclear Structure and Decay Data Network of Evaluations.

  16. Non-Linear Dynamics of Continuously Measured Bose-Einstein Condensates in One-Dimensional Harmonic Traps

    E-Print Network [OSTI]

    T. Yu. Ivanova; M. S. Samoylova; D. A. Ivanov

    2011-09-03T23:59:59.000Z

    Continuous center-of-mass position measurements performed on an interacting harmonically trapped Bose-gas are considered. Using both semi-analytical mean-field approach and completely quantum numerical technique based on positive P-representation, it is demonstrated that the atomic delocalization due to the measurement back action is smaller for a strongly interacting gas. The numerically calculated second-order correlation functions demonstrate appearance of atomic bunching as a result of the center-of-mass measurement. Though being rather small the bunching is present also for strongly interacting gas which is in contrast with the case of unperturbed gas. The performed analysis allows to speculate that for relatively strong interactions the size of atomic cloud determined with a single snapshot measurement can become smaller than the ground-state cloud size.

  17. Are the TRACE-P measurements representative of the western Pacific during March 2001?

    E-Print Network [OSTI]

    2004-01-01T23:59:59.000Z

    TRACE-P measurements representative of the western PacificTHE TRACE- P MEASUREMENTS REPRESENTATIVE? Pierce, R. B. , etTRACE-P measurements representative of the western Pacific

  18. 12.479 Trace-Element Geochemistry, Fall 2006

    E-Print Network [OSTI]

    Frey, Frederick August

    Focuses on element distribution in rocks and minerals using data obtained from natural and experimental systems. Emphasizes models describing trace-element partitioning and applications of trace-element geochemistry to ...

  19. 12.479 Trace-Element Geochemistry, Spring 2009

    E-Print Network [OSTI]

    Frey, Frederick

    The emphasis of this course is to use Trace Element Geochemistry to understand the origin and evolution of igneous rocks. The approach is to discuss the parameters that control partitioning of trace elements between phases ...

  20. A graphics architecture for ray tracing and photon mapping 

    E-Print Network [OSTI]

    Ling, Junyi

    2005-11-01T23:59:59.000Z

    and spatial locality, as well as eliminating unnecessary random memory accesses. A high level abstraction of the combined ray tracing and photon mapping streaming pipeline is introduced. Based on this abstraction, an e?cient ray tracing and photon...

  1. Steam Tracing...New Technologies for the 21st Century

    E-Print Network [OSTI]

    Pitzer, R. K.; Barth, R. E.; Bonorden, C.

    For decades, steam tracing has been an accepted practice in the heating of piping, vessels, and equipment. This paper presents recent product innovations such as "burn-safe" and "energy efficient" steam tracing products. For the many applications...

  2. A high-flux BEC source for mobile atom interferometers

    E-Print Network [OSTI]

    Jan Rudolph; Waldemar Herr; Christoph Grzeschik; Tammo Sternke; Alexander Grote; Manuel Popp; Dennis Becker; Hauke Müntinga; Holger Ahlers; Achim Peters; Claus Lämmerzahl; Klaus Sengstock; Naceur Gaaloul; Wolfgang Ertmer; Ernst M. Rasel

    2015-01-02T23:59:59.000Z

    Quantum sensors based on coherent matter-waves are precise measurement devices whose ultimate accuracy is achieved with Bose-Einstein condensates (BEC) in extended free fall. This is ideally realized in microgravity environments such as drop towers, ballistic rockets and space platforms. However, the transition from lab-based BEC machines to robust and mobile sources with comparable performance is a technological challenge. Here we report on the realization of a miniaturized setup, generating a flux of $4 \\times 10^5$ quantum degenerate $^{87}$Rb atoms every 1.6 s. Ensembles of $1 \\times 10^5$ atoms can be produced at a 1 Hz rate. This is achieved by loading a cold atomic beam directly into a multi-layer atom chip that is designed for efficient transfer from laser-cooled to magnetically trapped clouds. The attained flux of degenerate atoms is on par with current lab-based experiments while offering significantly higher repetition rates. The compact and robust design allows for mobile operation in a variety of demanding environments and paves the way for portable high-precision quantum sensors.

  3. A high-flux BEC source for mobile atom interferometers

    E-Print Network [OSTI]

    Rudolph, Jan; Grzeschik, Christoph; Sternke, Tammo; Grote, Alexander; Popp, Manuel; Becker, Dennis; Müntinga, Hauke; Ahlers, Holger; Peters, Achim; Lämmerzahl, Claus; Sengstock, Klaus; Gaaloul, Naceur; Ertmer, Wolfgang; Rasel, Ernst M

    2015-01-01T23:59:59.000Z

    Quantum sensors based on coherent matter-waves are precise measurement devices whose ultimate accuracy is achieved with Bose-Einstein condensates (BEC) in extended free fall. This is ideally realized in microgravity environments such as drop towers, ballistic rockets and space platforms. However, the transition from lab-based BEC machines to robust and mobile sources with comparable performance is a technological challenge. Here we report on the realization of a miniaturized setup, generating a flux of $4 \\times 10^5$ quantum degenerate $^{87}$Rb atoms every 1.6 s. Ensembles of $1 \\times 10^5$ atoms can be produced at a 1 Hz rate. This is achieved by loading a cold atomic beam directly into a multi-layer atom chip that is designed for efficient transfer from laser-cooled to magnetically trapped clouds. The attained flux of degenerate atoms is on par with current lab-based experiments while offering significantly higher repetition rates. The compact and robust design allows for mobile operation in a variety of...

  4. Universal bosonic tetramers of dimer-atom-atom structure

    E-Print Network [OSTI]

    A. Deltuva

    2012-03-28T23:59:59.000Z

    Unstable four-boson states having an approximate dimer-atom-atom structure are studied using momentum-space integral equations for the four-particle transition operators. For a given Efimov trimer the universal properties of the lowest associated tetramer are determined. The impact of this tetramer on the atom-trimer and dimer-dimer collisions is analyzed. The reliability of the three-body dimer-atom-atom model is studied.

  5. Universal bosonic tetramers of dimer-atom-atom structure

    E-Print Network [OSTI]

    Deltuva, A

    2012-01-01T23:59:59.000Z

    Unstable four-boson states having an approximate dimer-atom-atom structure are studied using momentum-space integral equations for the four-particle transition operators. For a given Efimov trimer the universal properties of the lowest associated tetramer are determined. The impact of this tetramer on the atom-trimer and dimer-dimer collisions is analyzed. The reliability of the three-body dimer-atom-atom model is studied.

  6. Ambient methods and apparatus for rapid laser trace constituent analysis

    DOE Patents [OSTI]

    Snyder, Stuart C. (Idaho Falls, ID); Partin, Judy K. (Idaho Falls, ID); Grandy, Jon D. (Idaho Falls, ID); Jeffery, Charles L. (Blackfoot, ID)

    2002-01-01T23:59:59.000Z

    A method and apparatus are disclosed for measuring trace amounts of constituents in samples by using laser induced breakdown spectroscopy and laser induced fluorescence under ambient conditions. The laser induced fluorescence is performed at a selected wavelength corresponding to an absorption state of a selected trace constituent. The intensity value of the emission decay signal which is generated by the trace constituent is compared to calibrated emission intensity decay values to determine the amount of trace constituent present.

  7. Quantum anomalous Hall effect with cold atoms trapped in a square lattice

    E-Print Network [OSTI]

    Liu, Xiong-Jun; Liu, Xin; Wu, Congjun; Sinova, Jairo

    2010-01-01T23:59:59.000Z

    -JUN LIU, XIN LIU, CONGJUN WU, AND JAIRO SINOVA PHYSICAL REVIEW A 81, 033622 (2010) represent the edge and bulk states, respectively. The light Bragg scattering directly measures the dynamical structure factor [23]: S(q, ?) = ? ky1 ,ky2 { 1? f [E...| #1; q0 the dynamical structure takes the general form S(q, ?) ? (|q| + ky0 )#5;2?(? ? vF q) + #8;0 ?#5;20 2t2aba2 1+ 3h???/(2q0atab) [1+ h???/(q0atab)]2 ? ( pi 2 + sin?1 ?1/2|q ? q0|? h??? ) #15;(? ? ?c), (11) where ?? = ? ?#8;0/2h...

  8. Hydrogen atom trapping in a self-organized one-dimensional dimer

    SciTech Connect (OSTI)

    Takami, Tsuyoshi, E-mail: takami@phys.sci.osaka-u.ac.jp [Department of Physics, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043 (Japan); Kawamura, Kazushi [Analytical Measurement Room, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043 (Japan)

    2014-09-01T23:59:59.000Z

    Metal–organic frameworks (MOFs) have attracted widespread attention owing to their unusual structure and properties produced by their nanospaces. However, many MOFs possess the similar three-dimensional frameworks, limiting their structural variety and operating capacity for hydrogen storage under ambient conditions. Here we report the synthesis and structural characterization of a single-crystal one-dimensional dimer whose structure, operating capacity, and physical mechanism contrast with those of existing MOFs. The hydrogen storage capacity of 2.6 wt.% is comparable to the highest capacity achieved by existing MOFs at room temperature. This exceptional storage capacity is realized by self-organization during crystal growth using a weak base.

  9. 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...

  10. 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).

  11. 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.

  12. 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

  13. 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...

  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. 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.

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. 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.

  1. Percolation mechanism through trapping/de-trapping process at defect states for resistive switching devices with structure of Ag/Si{sub x}C{sub 1?x}/p-Si

    SciTech Connect (OSTI)

    Liu, Yanhong; Gao, Ping; Li, La; Peng, Wei [School of Physics and Optoelectronic Engineering, Dalian University of Technology, No. 2 Linggong Road, Ganjingzi District, Dalian 116024 (China); Jiang, Xuening; Zhang, Jialiang [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Ministry of Education, Dalian University of Technology, No. 2 Linggong Road, Ganjingzi District, Dalian 116024 (China)

    2014-08-14T23:59:59.000Z

    Pure Si{sub x}C{sub 1?x} (x?>?0.5) and B-containing Si{sub x}C{sub 1?x} (x?>?0.5) based resistive switching devices (RSD) with the structure of Ag/Si{sub x}C{sub 1?x}/p-Si were fabricated and their switching characteristics and mechanism were investigated systematically. Percolation mechanism through trapping/ de-trapping at defect states was suggested for the switching process. Through the introduction of B atoms into Si{sub x}C{sub 1?x}, the density of defect states was reduced, then, the SET and RESET voltages were also decreased. Based on the percolation theory, the dependence of SET/RESET voltage on the density of defect states was analyzed. These results supply a deep understanding for the SiC-based RSD, which have a potential application in extreme ambient conditions.

  2. Trace anomaly of the conformal gauge field

    E-Print Network [OSTI]

    Sladkowski, J

    1993-01-01T23:59:59.000Z

    The proposed by Bastianelli and van Nieuwenhuizen new method of calculations of trace anomalies is applied in the conformal gauge field case. The result is then reproduced by the heat equation method. An error in previous calculation is corrected. It is pointed out that the introducing gauge symmetries into a given system by a field-enlarging transformation can result in unexpected quantum effects even for trivial configurations.

  3. HELSINKI UNIVERSITY OF TECHNOLOGY ENE-47.153 Trace elements and alkaliTrace elements and alkali

    E-Print Network [OSTI]

    Zevenhoven, Ron

    elements in fossil - and waste-derived fuelsTrace elements in fossil - and waste-derived fuels Coal Peat Heavy fuel oil Pet coke MSW RDF Wood Waste wood Waste paper Scrap tyres Sew. sludge Hg 0.02-3 ~0.07 .153 Behaviour of trace elements in coalBehaviour of trace elements in coal combustion flue gasescombustion flue

  4. The use of solvent extraction in trace metal analysis by atomic absorption spectroscopy

    E-Print Network [OSTI]

    Eddy, Raymond Douglas

    1968-01-01T23:59:59.000Z

    . , reagen4 grade. NamHPOn ~ 7H-. . G T ' Till 68 08 Fe . ?. 0. 0003'Ii. S~ diun; di. hy;!i'cg=n phosphate, J. T. Baker, rcag?nt grade. F. W. 138. 00. Sodium tartrate, J. T. Baker, reagent grade. Nae04H40e 2HnO F. W. 250. 08 Fe = 0. 0002/0. d... the sta!&dards ;&ere prepared. The solutions werc pipeti, ed. into a 125&-ml pear-sba d. separatory funnel and. 5 ml of 41 reagen4 sclurion &;as added. '!ne rsixture was shaken for I'ive s&inutes. 'The layers were allowed to separate snd th or- ganic...

  5. Atomic Force Microscope

    SciTech Connect (OSTI)

    Day, R.D.; Russell, P.E.

    1988-12-01T23:59:59.000Z

    The Atomic Force Microscope (AFM) is a recently developed instrument that has achieved atomic resolution imaging of both conducting and non- conducting surfaces. Because the AFM is in the early stages of development, and because of the difficulty of building the instrument, it is currently in use in fewer than ten laboratories worldwide. It promises to be a valuable tool for obtaining information about engineering surfaces and aiding the .study of precision fabrication processes. This paper gives an overview of AFM technology and presents plans to build an instrument designed to look at engineering surfaces.

  6. Iowa Powder Atomization Technologies

    ScienceCinema (OSTI)

    None

    2013-03-01T23:59:59.000Z

    The same atomization effect seen in a fuel injector is being applied to titanium metal resulting in fine titanium powders that are less than half the width of a human hair. Titanium melts above 3,000°F and is highly corrosive therefore requiring specialized containers. The liquid titanium is poured through an Ames Laboratory - USDOE patented tube which is intended to increase the energy efficiency of the atomization process, which has the ability to dramatically decrease the cost of fine titanium powders. This novel process could open markets for green manufacturing of titanium components from jet engines to biomedical implants.

  7. Iowa Powder Atomization Technologies

    SciTech Connect (OSTI)

    None

    2012-01-01T23:59:59.000Z

    The same atomization effect seen in a fuel injector is being applied to titanium metal resulting in fine titanium powders that are less than half the width of a human hair. Titanium melts above 3,000°F and is highly corrosive therefore requiring specialized containers. The liquid titanium is poured through an Ames Laboratory - USDOE patented tube which is intended to increase the energy efficiency of the atomization process, which has the ability to dramatically decrease the cost of fine titanium powders. This novel process could open markets for green manufacturing of titanium components from jet engines to biomedical implants.

  8. 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.

  9. 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.

  10. 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

  11. Trace Analytical Techniques for Nuclear Forensics

    SciTech Connect (OSTI)

    Halverson, J.E.

    1999-04-28T23:59:59.000Z

    Over the history of the Savannah River Site, the Savannah River Technology Center (SRTC) has developed high sensitivity analytical capabilities in support of the Site's Environmental Monitoring Program and nuclear material protection process. Many of these techniques are applicable to the developing need for nuclear forensic analysis capabilities. Radiological and critically control procedures are in place at the SRTC, as well as clean room practices, to minimize the potential for a radiological evidentiary sample to contaminate personnel and the facility, as well as to minimize contaminating the sample thus rendering it useless by law enforcement agencies. Some of the trace analytical techniques available at the SRTC include ultra-low-level gamma and alpha spectrometry, high-sensitivity thermal ionization mass spectrometry, time-of-flight secondary ion mass spectrometry and trace organic analyses. These techniques have been tested during a planned domestic smuggling exercise and in the analysis of an unknown sample.In the event of an interdiction involving the illegal use or movement of radioactive material by U.S. law enforcement agencies (local, state or federal) forensic analyses will be used in developing and building a legal case against the perpetrators. The Savannah River Technology Center (SRTC) at the U.S. Department of Energy's Savannah River Site, a former nuclear production site currently conducting nuclear material stabilization missions, located in Aiken South Carolina, has a long history of performing trace analytical analyses for environmental monitoring. Many of these techniques are also applicable to nuclear forensic analyses. A summary of the trace analytical techniques used at the SRTC, which are applicable to Nuclear Forensics, is presented in this paper.Contamination control, of facilities and personnel involved in the analytical analyses, as well as preventing contamination of the sample, is a unique challenge for nuclear forensic analyses. A discussion of sample handling and contamination control procedures is included in this paper. Some of the applicable analytical techniques available at the SRTC for nuclear forensic analyses include: ultra-low-level gamma and alpha spectroscopy, high-sensitivity thermal-ionization mass spectrometry (TIMS), time-of-flight secondary ion mass spectrometry (TOF-SIMS), and trace organic analyses. Results from analyses of special nuclear material (SNM) standards, materials from nuclear smuggling exercises, and materials of unknown origin will be presented.

  12. ScalaTrace: Tracing, Analysis and Modeling of HPC Codes at Scale

    SciTech Connect (OSTI)

    Mueller, F; Wu, X; Schulz, M; de Supinski, B; Gamblin, T

    2010-03-31T23:59:59.000Z

    Characterizing the communication behavior of large-scale applications is a difficult and costly task due to code/system complexity and their long execution times. An alternative to running actual codes is to gather their communication traces and then replay them, which facilitates application tuning and future procurements. While past approaches lacked lossless scalable trace collection, we contribute an approach that provides orders of magnitude smaller, if not near constant-size, communication traces regardless of the number of nodes while preserving structural information. We introduce intra- and inter-node compression techniques of MPI events, we develop a scheme to preserve time and causality of communication events, and we present results of our implementation for BlueGene/L. Given this novel capability, we discuss its impact on communication tuning and on trace extrapolation. To the best of our knowledge, such a concise representation of MPI traces in a scalable manner combined with time-preserving deterministic MPI call replay are without any precedence.

  13. VOLUME 87, NUMBER 25 P H Y S I C A L R E V I E W L E T T E R S 17 DECEMBER 2001 Ion-Trap Quantum Logic Using Long-Wavelength Radiation

    E-Print Network [OSTI]

    Wunderlich, Christof

    radiation in the radiofrequency or microwave regime. DOI: 10.1103/PhysRevLett.87.257904 PACS numbers: 03 Logic Using Long-Wavelength Radiation Florian Mintert1 and Christof Wunderlich2,* 1 I. Institut für radiation; the atom with mass m is trapped in a harmonic potential characterized by angular frequency vl

  14. Elements & Compounds Atoms (Elements)

    E-Print Network [OSTI]

    Frey, Terry

    #12;Elements & Compounds #12;Atoms (Elements) Molecules (Compounds) Cells Elements & Compounds #12 #12;First shell Second shell Third shell Hydrogen 1H Lithium 3Li Sodium 11Na Beryllium 4Be Magnesium energy Higher energy (a) A ball bouncing down a flight of stairs provides an analogy for energy levels

  15. TCgen 2.0: A Tool to Automatically Generate Lossless Trace Compressors Martin Burtscher

    E-Print Network [OSTI]

    Burtscher, Martin

    TCgen 2.0: A Tool to Automatically Generate Lossless Trace Compressors Martin Burtscher Computer of TCgen, a tool for generating portable lossless trace compressors based on user-provided trace format for translating user-provided trace descriptions into fast and effective trace compressors. A typical trace

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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...

  1. 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

  2. 1. Introduction to the relative trace formula Give an idea of the relative trace formula along any of the sources [CPS90,

    E-Print Network [OSTI]

    Ould Ahmedou, Mohameden

    1. Introduction to the relative trace formula Give an idea of the relative trace formula along any (91h:11042) [Jac05] Herv´e Jacquet, A guide to the relative trace formula, Automorphic representations2192826 (2006g:11100) [Lap10] Erez M. Lapid, Some applications of the trace formula and the relative trace

  3. Effect of reduction of trap charge carrier density in organic field effect transistors by surface treatment of dielectric layer

    SciTech Connect (OSTI)

    Dagar, Janardan; Yadav, Vandana; Kumar Singh, Rajiv; Suman, C. K.; Srivastava, Ritu, E-mail: ritu@mail.nplindia.org [Physics of Energy Harvesting Division, CSIR-National Physical Laboratory, CSIR-Network of Institute for Solar Energy (NISE), Dr. K.S.Krishnan Road, New Delhi 110012 (India); Tyagi, Priyanka [Physics of Energy Harvesting Division, CSIR-National Physical Laboratory, CSIR-Network of Institute for Solar Energy (NISE), Dr. K.S.Krishnan Road, New Delhi 110012 (India); Center for Applied Research in Electronics, Indian Institute of Technology Delhi, New Delhi 110016 (India)

    2013-12-14T23:59:59.000Z

    In this work, we have studied the effect of surface treatment of SiO{sub 2} dielectric layer on the reduction of the trap charge carrier density at dielectric/semiconducting interface by fabricating a metal–insulator–semiconductor (MIS) device using ?, ?-dihexylcarbonylquaterthiophene as semiconducting layer. SiO{sub 2} dielectric layer has been treated with 1,1,1,3,3,3-hexamethyldisilazane (HMDS) to modify the chemical group acting as charge traps. Capacitance-voltage measurements have been performed on MIS devices fabricated on SiO{sub 2} and HMDS treated SiO{sub 2}. These data have been used for the calculation of trap charge carrier density and Debye length at the dielectric-semiconductor interface. The calculated trap charge carrier density has been found to reduce from (2.925?±?0.049) × 10{sup 16}?cm{sup ?3} to (2.025?±?0.061) × 10{sup 16}?cm{sup ?3} for the MIS device with HMDS treated SiO{sub 2} dielectric in comparison to that of untreated SiO{sub 2}. Next, the effect of reduction in trap charge carrier density has been studied on the performance of organic field effect transistors. The improvement in the device parameters like mobility, on/off ratio, and gate leakage current has been obtained with the effect of the surface treatment. The charge carrier mobility has been improved by a factor of 2 through this treatment. Further, the influence of the treatment was observed by atomic force microscope and Fourier transform infrared spectroscopy techniques.

  4. 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 ...

  5. 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.

  6. Coherence Induced by Incoherent Pumping Field and Decay Process in Three-level $?$ Type Atomic System

    E-Print Network [OSTI]

    Bao-Quan Ou; Lin-Mei Liang; Cheng-Zu Li

    2007-12-25T23:59:59.000Z

    Following the method of Victor V. Kozlov et al.[PhysRevA. 74. 063829],we inspect the coherence induced by incoherent pump and spontaneous decay process in $\\Lambda$ type three-level atomic system with degenerated lower duplicate levels. The system shows a coherent population trapping state and multi-steady states characteristic in different conditions. Interestingly, two kinds of steady states generated by the system in different sets of pumping and decaying parameters, the "singlet" state and the "triplet" state, exhibit stable or unstable characteristics under the action of pumping field and vacuum reservoir, which promise fruitful applications to atomic coherence and interference in quantum optics.

  7. Natural orbits of atomic Cooper pairs in a nonuniform Fermi gas

    E-Print Network [OSTI]

    Y. H. Pong; C. K. Law

    2006-05-08T23:59:59.000Z

    We examine the basic mode structure of atomic Cooper pairs in an inhomogeneous Fermi gas. Based on the properties of Bogoliubov quasi-particle vacuum, the single particle density matrix and the anomalous density matrix share the same set of eigenfunctions. These eigenfunctions correspond to natural pairing orbits associated with the BCS ground state. We investigate these orbits for a Fermi gas in a spherical harmonic trap, and construct the wave function of a Cooper pair in the form of Schmidt decomposition. The issue of spatial quantum entanglement between constituent atoms in a pair is addressed.

  8. Atom-by-atom nucleation and growth of graphene nanopores

    E-Print Network [OSTI]

    Golovchenko, Jene A.

    Atom-by-atom nucleation and growth of graphene nanopores Christopher J. Russoa,b and J. A February 17, 2012 (received for review December 9, 2011) Graphene is an ideal thin membrane substrate structures in graphene with atomic preci- sion. It consists of inducing defect nucleation centers with ener

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Final report on LDRD project : narrow-linewidth VCSELs for atomic microsystems.

    SciTech Connect (OSTI)

    Chow, Weng Wah; Geib, Kent Martin; Peake, Gregory Merwin; Serkland, Darwin Keith

    2011-09-01T23:59:59.000Z

    Vertical-cavity surface-emitting lasers (VCSELs) are well suited for emerging photonic microsystems due to their low power consumption, ease of integration with other optical components, and single frequency operation. However, the typical VCSEL linewidth of 100 MHz is approximately ten times wider than the natural linewidth of atoms used in atomic beam clocks and trapped atom research, which degrades or completely destroys performance in those systems. This report documents our efforts to reduce VCSEL linewidths below 10 MHz to meet the needs of advanced sub-Doppler atomic microsystems, such as cold-atom traps. We have investigated two complementary approaches to reduce VCSEL linewidth: (A) increasing the laser-cavity quality factor, and (B) decreasing the linewidth enhancement factor (alpha) of the optical gain medium. We have developed two new VCSEL devices that achieved increased cavity quality factors: (1) all-semiconductor extended-cavity VCSELs, and (2) micro-external-cavity surface-emitting lasers (MECSELs). These new VCSEL devices have demonstrated linewidths below 10 MHz, and linewidths below 1 MHz seem feasible with further optimization.

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

    SciTech Connect (OSTI)

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

    2014-07-21T23:59:59.000Z

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

  15. Atomic phenomena in dense plasmas

    SciTech Connect (OSTI)

    Weisheit, J.C.

    1981-03-01T23:59:59.000Z

    The following chapters are included: (1) the plasma environment, (2) perturbations of atomic structure, (3) perturbations of atomic collisions, (4) formation of spectral lines, and (5) dielectronic recombination. (MOW)

  16. NARROW ATOMIC FEATURES FROM RAPIDLY SPINNING NEUTRON STARS

    SciTech Connect (OSTI)

    Bauboeck, Michi; Psaltis, Dimitrios; Oezel, Feryal, E-mail: mbaubock@email.arizona.edu, E-mail: dpsaltis@email.arizona.edu, E-mail: fozel@email.arizona.edu [Astronomy Department, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States)] [Astronomy Department, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States)

    2013-04-01T23:59:59.000Z

    Neutron stars spinning at moderate rates ({approx}300-600 Hz) become oblate in shape and acquire a nonzero quadrupole moment. In this paper, we calculate the profiles of atomic features from such neutron stars using a ray-tracing algorithm in the Hartle-Thorne approximation. We show that line profiles acquire cores that are much narrower than the widths expected from pure Doppler effects for a large range of observer inclinations. As a result, the effects of both the oblateness and the quadrupole moments of neutron stars need to be taken into account when aiming to measure neutron-star radii from rotationally broadened lines. Moreover, the presence of these narrow cores substantially increases the likelihood of detecting atomic lines from rapidly spinning neutron stars.

  17. atoms: Topics by E-print Network

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

    with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory...

  18. Spectra of In-like Tungsten, $W^{25+}$, from the Shanghai permanent magnet electron beam ion trap

    E-Print Network [OSTI]

    Li, W; Shi, Z; Fei, Z; R,; Zhao,; Brage, T; Huldt, S; Hutton, R; Zou, Y

    2015-01-01T23:59:59.000Z

    Three visible lines of M1 transitions from In-like W were recorded using the Shanghai permanent magnet electron beam ion trap. The experimental wavelengths were measured as 493.84 $\\pm$ 0.15, 226.97 $\\pm$ 0.13 and 587.63 $\\pm$ 0.23 nm (vacuum wavelengths). These results are in good agreement with theoretical predictions obtained using large-scale Relativistic Many-Body Perturbation Theory, in the form of the Flexible Atomic Code, and some explorations with the Muliconfiguration Dirac-Hartree-Fock code GRASP2K.

  19. 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...

  20. 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

  1. 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.

  2. A microfabricated atomic clock

    SciTech Connect (OSTI)

    Knappe, Svenja; Shah, Vishal; Schwindt, Peter D.D.; Hollberg, Leo; Kitching, John; Liew, Li-Anne; Moreland, John [Time and Frequency Division, National Institute of Standards and Technology, Boulder, Colorado 80305-3328 (United States); Electromagnetics Division, National Institute of Standards and Technology, Boulder, Colorado 80305-3328 (United States)

    2004-08-30T23:59:59.000Z

    Fabrication techniques usually applied to microelectromechanical systems (MEMS) are used to reduce the size and operating power of the core physics assembly of an atomic clock. With a volume of 9.5 mm{sup 3}, a fractional frequency instability of 2.5x10{sup -10} at 1 s of integration, and dissipating less than 75 mW of power, the device has the potential to bring atomically precise timing to hand-held, battery-operated devices. In addition, the design and fabrication process allows for wafer-level assembly of the structures, enabling low-cost mass-production of thousands of identical units with the same process sequence, and easy integration with other electronics.

  3. Delay in Atomic Photoionization

    SciTech Connect (OSTI)

    Kheifets, A. S. [Research School of Physical Sciences, Australian National University, Canberra ACT 0200 (Australia); Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106-4030 (United States); Ivanov, I. A. [Research School of Physical Sciences, Australian National University, Canberra ACT 0200 (Australia)

    2010-12-03T23:59:59.000Z

    We analyze the time delay between emission of photoelectrons from the outer valence ns and np subshells in noble gas atoms following absorption of an attosecond extreme ultraviolet pulse. Various processes such as elastic scattering of the photoelectron on the parent ion and many-electron correlation affect the apparent 'time zero' when the photoelectron leaves the atom. This qualitatively explains the time delay between photoemission from the 2s and 2p subshells of Ne as determined experimentally by attosecond streaking [Science 328, 1658 (2010)]. However, with our extensive numerical modeling, we were only able to account for less than half of the measured time delay of 21{+-}5 as. We argue that the extreme ultraviolet pulse alone cannot produce such a large time delay and it is the streaking IR field that is most likely responsible for this effect.

  4. 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.

  5. In situ measurements of Krypton in Xenon gas with a quadrupole mass spectrometer following a cold-trap at a temporarily reduced pumping speed

    E-Print Network [OSTI]

    Ethan Brown; Stephan Rosendahl; Christian Huhmann; Christian Weinheimer; Hans Kettling

    2012-12-20T23:59:59.000Z

    A new method for measuring trace amounts of krypton in xenon using a cold trap with a residual gas analyzer has been developed, which achieves an increased sensitivity by temporarily reducing the pumping speed while expending a minimal amount of xenon. By partially closing a custom built butterfly valve between the measurement chamber and the turbomolecular pump, a sensitivity of 40 ppt has been reached. This method has been tested on an ultra-pure gas sample from Air Liquide with an unknown intrinsic krypton concentration, yielding a krypton concentration of $330 \\pm 200$ ppt.

  6. EBIT - Electronic Beam Ion Trap: N Divison experimental physics annual report 1995

    SciTech Connect (OSTI)

    Schneider, D. [ed.

    1996-10-01T23:59:59.000Z

    The multi-faceted research effort of the EBIT (Electron Beam Ion Trap) program in N-Division of the Physics and Space Technology Department at Lawrence Livermore National Laboratory (LLNL) continues to contribute significant results to the physical sciences from studies with low energy very highly charged heavy ions. The EBIT program attracts a number of collaborators from the US and abroad for the different projects. The collaborations are partly carried out through participating graduate students demonstrating the excellent educational capabilities at the LLNL EBIT facilities. Moreover, participants from Historically Black Colleges and Universities are engaged in the EBIT project. This report describes EBIT work for 1995 in atomic structure measurements and radiative transition probabilities, spectral diagnostics for laboratory and astrophysical plasmas, ion/surface interaction studies, electron-ion interactions studies, retrap and ion collisions, and instrumental development.

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

    E-Print Network [OSTI]

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

    2005-05-15T23:59:59.000Z

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

  8. Correlation measurements in nuclear {beta}-decay using traps and polarized low energy beams

    SciTech Connect (OSTI)

    Naviliat-Cuncic, Oscar [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States)

    2013-05-06T23:59:59.000Z

    Precision measurements in nuclear {beta}-decay provide sensitive means to test discrete symmetries in the weak interaction and to determine some of the fundamental constants in semi-leptonic decays, like the coupling of the lightest quarks to charged weak bosons. The main motivation of such measurements is to find deviations from Standard Model predictions as possible indications of new physics. In this contribution I will focus on two topics related to precision measurements in nuclear {beta}-decay: i) the determination of the V{sub ud} element of the Cabibbo-Kobayashi-Maskawa quark mixing matrix from nuclear mirror transitions and ii) the search for exotic scalar or tensor contributions from {beta}{nu} angular correlations. The purpose is to underline the role being played by experimental techniques based on the confinement of radioactive species with atom and ion traps as well as the plans to use low energy polarized beams.

  9. Trace Element Geochemical Zoning in the Roosevelt Hot Springs...

    Open Energy Info (EERE)

    Capuano. 1980. Trace Element Geochemical Zoning in the Roosevelt Hot Springs Thermal Area, Utah. In: Transactions. GRC Annual Meeting; 09091980; Salt Lake City, UT. Salt...

  10. Tracing And Quantifying Magmatic Carbon Discharge In Cold Groundwaters...

    Open Energy Info (EERE)

    Tracing And Quantifying Magmatic Carbon Discharge In Cold Groundwaters- Lessons Learned From Mammoth Mountain, USA Jump to: navigation, search OpenEI Reference LibraryAdd to...

  11. Monitoring Trace Radionuclides by ICP Mass Spectrometry with...

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

    extensive monitoring programs for trace radionuclides relevant to the observation of illicit nuclear activities. FUNDING SOURCE: United States Department of Energy NA22 FOR MORE...

  12. The Effects of Trace Contaminants on Catalytic Processing of...

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

    Processing of Biomass-Derived Feedstocks . Abstract: Trace components in biomass feedstocks are potential catalyst poisons when catalytically processing these materials to...

  13. Day After Trinity: Oppenheimer and the Atomic Bomb

    SciTech Connect (OSTI)

    Documentary

    2005-10-31T23:59:59.000Z

    On October 31st at 4:00 pm in Panofsky Auditorium SLAC’s Colloquium Series will present the exceptional Oscar-nominated documentary The Day After Trinity. The film offers invaluable insight into historic events which have forever changed the face of our world – this screening should not to be missed. After witnessing the tremendous destructive power of the atomic bomb, J. Robert Oppenheimer declared “I have become death”. Still topically relevant a quarter of a century since its release, Director Jon Else’s documentary uses interviews, archival footage, and narration to reveal the internal landscape of the man whose leadership at Los Alamos, New Mexico, defined the rise of the Manhattan Project and the beginning of the Atomic Age. The Day After Trinity traces the unexpected path of Oppenheimer’s career - from his formation of the Los Alamos colony and the first successful atomic bomb detonation at the Trinity test site in 1945, to his final years spent branded as a security risk and excluded from the atomic energy research he pioneered due to his opposition to the development of the Hydrogen bomb.

  14. Optics and interferometry with atoms and molecules

    E-Print Network [OSTI]

    Cronin, Alexander D.

    Interference with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory fields technique used in atomic ...

  15. 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.

  16. 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.

  17. Theory of ultracold atomic Fermi gases

    SciTech Connect (OSTI)

    Giorgini, Stefano; Pitaevskii, Lev P.; Stringari, Sandro [Dipartimento di Fisica, Universita di Trento and CNR-INFM BEC Center, I-38050 Povo, Trento (Italy); Dipartimento di Fisica, Universita di Trento and CNR-INFM BEC Center, I-38050 Povo, Trento, Italy and Kapitza Institute for Physical Problems, ul. Kosygina 2, 117334 Moscow (Russian Federation); Dipartimento di Fisica, Universita di Trento and CNR-INFM BEC Center, I-38050 Povo, Trento (Italy)

    2008-10-15T23:59:59.000Z

    The physics of quantum degenerate atomic Fermi gases in uniform as well as in harmonically trapped configurations is reviewed from a theoretical perspective. Emphasis is given to the effect of interactions that play a crucial role, bringing the gas into a superfluid phase at low temperature. In these dilute systems, interactions are characterized by a single parameter, the s-wave scattering length, whose value can be tuned using an external magnetic field near a broad Feshbach resonance. The BCS limit of ordinary Fermi superfluidity, the Bose-Einstein condensation (BEC) of dimers, and the unitary limit of large scattering length are important regimes exhibited by interacting Fermi gases. In particular, the BEC and the unitary regimes are characterized by a high value of the superfluid critical temperature, on the order of the Fermi temperature. Different physical properties are discussed, including the density profiles and the energy of the ground-state configurations, the momentum distribution, the fraction of condensed pairs, collective oscillations and pair-breaking effects, the expansion of the gas, the main thermodynamic properties, the behavior in the presence of optical lattices, and the signatures of superfluidity, such as the existence of quantized vortices, the quenching of the moment of inertia, and the consequences of spin polarization. Various theoretical approaches are considered, ranging from the mean-field description of the BCS-BEC crossover to nonperturbative methods based on quantum Monte Carlo techniques. A major goal of the review is to compare theoretical predictions with available experimental results.

  18. Atomic Collapse Observed

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWP TWPAlumni AlumniFederalAshley BoyleAn overhead viewAtom-split it

  19. Can the trace formula describe weak localisation?

    E-Print Network [OSTI]

    Robert S. Whitney; Igor V. Lerner; Robert A. Smith

    1999-02-24T23:59:59.000Z

    We attempt to systematically derive perturbative quantum corrections to the Berry diagonal approximation of the two-level correlation function (TLCF) for chaotic systems. To this end, we develop a ``weak diagonal approximation'' based on a recent description of the first weak localisation correction to conductance in terms of the Gutzwiller trace formula. This semiclassical method is tested by using it to derive the weak localisation corrections to the TLCF for a semiclassically disordered system. Unfortunately the method is unable to correctly reproduce the ``Hikami boxes'' (the relatively small regions where classical paths are glued together by quantum processes). This results in the method failing to reproduce the well known weak localisation expansion. It so happens that for the first order correction it merely produces the wrong prefactor. However for the second order correction, it is unable to reproduce certain contributions, and leads to a result which is of a different form to the standard one.

  20. The Mission and Technology of a Gas Dynamic Trap Neutron Source for Fusion Material and Component Testing and Qualification

    SciTech Connect (OSTI)

    Molvik, A W; Simonen, T C

    2009-07-17T23:59:59.000Z

    This report summarizes discussions and conclusions of the workshop to 'Assess The Mission and Technology of a Gas Dynamic Trap Neutron Source for Fusion Material and Component Testing and Qualification'. The workshop was held at LBNL, Berkeley, CA on March 12, 2009. Most workshop attendees have worked on magnetic mirror systems, several have worked on similar neutron source designs, and others are knowledgeable of materials, fusion component, and neutral beams The workshop focused on the gas dynamic trap DT Neutron Source (DTNS) concept being developed at the Budker Institute of Nuclear Physics (BINP) in Novosibirsk, Russia. The DTNS may be described as a line source of neutrons, in contrast to a spallation or a D-Lithium source with neutrons beaming from a point, or a tokamak volume source. The DTNS is a neutral beam driven linear plasma system with magnetic mirrors to confine the energetic deuterium and tritium beam injected ions, which produce the 14 MeV neutrons. The hot ions are imbedded in warm-background plasma, which traps the neutral atoms and provides both MHD and micro stability to the plasma. The 14 MeV neutron flux ranges typically at the level of 1 to 4 MW/m2.

  1. Generating Entanglement between Atomic Spins with Low-Noise Probing of an Optical Cavity

    E-Print Network [OSTI]

    Cox, Kevin C; Greve, Graham P; Thompson, James K

    2015-01-01T23:59:59.000Z

    Atomic projection noise limits the ultimate precision of all atomic sensors, including clocks, inertial sensors, magnetometers, etc. The independent quantum collapse of $N$ atoms into a definite state (for example spin up or down) leads to an uncertainty $\\Delta \\theta_{SQL}=1/\\sqrt{N}$ in the estimate of the quantum phase accumulated during a Ramsey sequence or its many generalizations. This phase uncertainty is referred to as the standard quantum limit. Creating quantum entanglement between the $N$ atoms can allow the atoms to partially cancel each other's quantum noise, leading to reduced noise in the phase estimate below the standard quantum limit. Recent experiments have demonstrated up to $10$~dB of phase noise reduction relative to the SQL by making collective spin measurements. This is achieved by trapping laser-cooled Rb atoms in an optical cavity and precisely measuring the shift of the cavity resonance frequency by an amount that depends on the number of atoms in spin up. Detecting the probe light ...

  2. Generating Entanglement between Atomic Spins with Low-Noise Probing of an Optical Cavity

    E-Print Network [OSTI]

    Kevin C. Cox; Joshua M. Weiner; Graham P. Greve; James K. Thompson

    2015-04-20T23:59:59.000Z

    Atomic projection noise limits the ultimate precision of all atomic sensors, including clocks, inertial sensors, magnetometers, etc. The independent quantum collapse of $N$ atoms into a definite state (for example spin up or down) leads to an uncertainty $\\Delta \\theta_{SQL}=1/\\sqrt{N}$ in the estimate of the quantum phase accumulated during a Ramsey sequence or its many generalizations. This phase uncertainty is referred to as the standard quantum limit. Creating quantum entanglement between the $N$ atoms can allow the atoms to partially cancel each other's quantum noise, leading to reduced noise in the phase estimate below the standard quantum limit. Recent experiments have demonstrated up to $10$~dB of phase noise reduction relative to the SQL by making collective spin measurements. This is achieved by trapping laser-cooled Rb atoms in an optical cavity and precisely measuring the shift of the cavity resonance frequency by an amount that depends on the number of atoms in spin up. Detecting the probe light with high total efficiency reduces excess classical and quantum back-action of the probe. Here we discuss recent progress and a technique for reducing the relative frequency noise between the probe light and the optical cavity, a key requirement for further advances.

  3. 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...

  4. 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...

  5. 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...

  6. 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 ...

  7. 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).

  8. 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...

  9. 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.

  10. 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...

  11. 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

  12. 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.

  13. 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

  14. 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.

  15. 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.

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

    E-Print Network [OSTI]

    Atwater, Harry

    Solar cell efficiency enhancement via light trapping in printable resonant dielectric nanosphere´de´rale de Lausanne (EPFL), Institute of Microengineering (IMT), Photovoltaics and Thin Film Electronics, photovoltaics, resonant dielectric structures, solar cells * Corresponding author: e-mail jgrandid

  17. 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 ...

  18. Realization of Bose-Einstein condensates in lower dimensions Bose-Einstein condensates of sodium atoms have been prepared in optical and

    E-Print Network [OSTI]

    Realization of Bose-Einstein condensates in lower dimensions Bose-Einstein condensates of sodium dimensions exceeds the interaction energy between atoms. This realized condensates of lower dimensionality [1]. In anisotropic traps, a primary indicator of crossing the transition temperature for Bose- Einstein condensation

  19. Atomic Energy Commission Takes Over Responsibility for all Atomic...

    National Nuclear Security Administration (NNSA)

    Takes Over Responsibility for all Atomic Energy Programs | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile...

  20. 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.

  1. 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.

  2. 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...

  3. 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.

  4. 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.

  5. 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

  6. 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

  7. Fixed Space of Positive Trace-Preserving Super-Operators

    E-Print Network [OSTI]

    Ansis Rosmanis

    2011-09-15T23:59:59.000Z

    We examine the fixed space of positive trace-preserving super-operators. We describe a specific structure that this space must have and what the projection onto it must look like. We show how these results, in turn, lead to an alternative proof of the complete characterization of the fixed space of completely positive trace-preserving super-operators.

  8. Accuracy of Memory Reference Traces of Parallel Computations

    E-Print Network [OSTI]

    Holliday, Mark A.

    , the trace-driven simulator uses the intrinsic traces and the sequence of loads and stores before the current cy- cle, to determine the next address. The mapping between load and store sequences and next addresses to issue, sometimes, requires partial program reexecution. Programs that do not require partial

  9. Initial conditions for paraxial ray tracing in inhomogeneous anisotropic media

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    , theoretical seismology, seismic anisotropy, wave propagation 1 Introduction By standard kinematic ray tracing and in numerical modelling and interpretation of high-frequency seismic wave #12;elds propagating in inhomogeneous to such important quantities as geometrical spreading and ray amplitudes. The limitations of kinematic ray tracing

  10. 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.

  11. Quantum transport in ultracold atoms

    E-Print Network [OSTI]

    Chih-Chun Chien; Sebastiano Peotta; Massimiliano Di Ventra

    2015-04-11T23:59:59.000Z

    Ultracold atoms confined by engineered magnetic or optical potentials are ideal systems for studying phenomena otherwise difficult to realize or probe in the solid state because their atomic interaction strength, number of species, density, and geometry can be independently controlled. This review focuses on quantum transport phenomena in atomic gases that mirror and oftentimes either better elucidate or show fundamental differences with those observed in mesoscopic and nanoscopic systems. We discuss significant progress in performing transport experiments in atomic gases, contrast similarities and differences between transport in cold atoms and in condensed matter systems, and survey inspiring theoretical predictions that are difficult to verify in conventional setups. These results further demonstrate the versatility offered by atomic systems in the study of nonequilibrium phenomena and their promise for novel applications.

  12. 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.

  13. 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.

  14. 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.

  15. Observation of recoil-induced resonances and electromagnetically induced absorption of diffuse light by cold atoms

    SciTech Connect (OSTI)

    Zhang Wenzhuo [Key Laboratory of Quantum Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Graduate University of the Chinese Academy of Sciences, Beijing 100039 (China); Cheng Huadong; Wang Yuzhu [Key Laboratory of Quantum Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Liu Liang [Key Laboratory of Quantum Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062 (China)

    2009-05-15T23:59:59.000Z

    In this paper we report an experiment on the observation of the recoil-induced resonances (RIR) and electromagnetically induced absorption (EIA) of cold {sup 87}Rb atoms in diffuse light. The pump light of the RIR and the EIA comes from the diffuse light in an integrating sphere, which also serves the cooling light. We measured the RIR and the EIA signal varying with the detuning of the diffuse laser light, and also measured the number and the temperature of the cold atoms at the different detunings. The mechanism of RIR and EIA in the configuration with diffuse-light pumping and laser probing are discussed, and the difference between the nonlinear spectra of cold atoms in a diffuse-light cooling system and in a magneto-optical trap is studied.

  16. Creation of effective magnetic fields in optical lattices: The Hofstadter butterfly for cold neutral atoms

    E-Print Network [OSTI]

    D. Jaksch; P. Zoller

    2003-04-04T23:59:59.000Z

    We investigate the dynamics of neutral atoms in a 2D optical lattice which traps two distinct internal states of the atoms in different columns. Two Raman lasers are used to coherently transfer atoms from one internal state to the other, thereby causing hopping between the different columns. By adjusting the laser parameters appropriately we can induce a non vanishing phase of particles moving along a closed path on the lattice. This phase is proportional to the enclosed area and we thus simulate a magnetic flux through the lattice. This setup is described by a Hamiltonian identical to the one for electrons on a lattice subject to a magnetic field and thus allows us to study this equivalent situation under very well defined controllable conditions. We consider the limiting case of huge magnetic fields -- which is not experimentally accessible for electrons in metals -- where a fractal band structure, the Hofstadter butterfly, characterizes the system.

  17. Towards a Re-definition of the Second Based on Optical Atomic Clocks

    E-Print Network [OSTI]

    Riehle, Fritz

    2015-01-01T23:59:59.000Z

    The rapid increase in accuracy and stability of optical atomic clocks compared to the caesium atomic clock as primary standard of time and frequency asks for a future re-definition of the second in the International System of Units (SI). The status of the optical clocks based on either single ions in radio-frequency traps or on neutral atoms stored in an optical lattice is described with special emphasis of the current work at the Physikalisch-Technische Bundesanstalt (PTB). Besides the development and operation of different optical clocks with estimated fractional uncertainties in the 10^-18 range, the supporting work on ultra-stable lasers as core elements and the means to compare remote optical clocks via transportable standards, optical fibers, or transportable clocks is reported. Finally, the conditions, methods and next steps are discussed that are the prerequisites for a future re-definition of the second.

  18. Coherent Atom Optics with fast metastable rare gas atoms

    SciTech Connect (OSTI)

    Grucker, J.; Baudon, J.; Karam, J.-C.; Perales, F.; Vassilev, G.; Ducloy, M. [Laboratoire de Physique des Lasers, Universite Paris 13, Avenue J.B. Clement, 93430-Villetaneuse (France); Bocvarski, V. [Institute of Physics, Pregrevica 118, 11080 - Belgrade-Zemun (Serbia and Montenegro)

    2006-12-01T23:59:59.000Z

    Coherent atom optics experiments making use of an ultra-narrow beam of fast metastable atoms generated by metastability exchange are reported. The transverse coherence of the beam (coherence radius of 1.7 {mu}m for He*, 1.2 {mu}m for Ne*, 0.87 {mu}m for Ar*) is demonstrated via the atomic diffraction by a non-magnetic 2{mu}m-period reflection grating. The combination of the non-scalar van der Waals (vdW) interaction with the Zeeman interaction generated by a static magnetic field gives rise to ''vdW-Zeeman'' transitions among Zeeman sub-levels. Exo-energetic transitions of this type are observed with Ne*(3P2) atoms traversing a copper micro-slit grating. They can be used as a tunable beam splitter in an inelastic Fresnel bi-prism atom interferometer.

  19. Isotope Effects on Delayed Annihilation Time Spectra of Antiprotonic Helium Atoms in Low-Temperature Gas

    E-Print Network [OSTI]

    Ketzer, B; Daniel, H; Von Egidy, T; Niestroj, A; Schmid, S; Schmid, W; Yamazaki, T; Sugai, I; Nakayoshi, K; Hayano, R S; Maas, F E; Torii, H A; Ishikawa, T; Tamura, H; Morita, N; Horváth, D; Eades, John; Widmann, E

    1996-01-01T23:59:59.000Z

    The delayed annihilation time spectra (DATS) of antiprotonic helium atoms have been studied in isotopically pure low temperature ^3He and ^4He gas at various densities. The DATS taken at 5.8~K and 400~mbar are very similar in shape except for i) a small difference in the time scale and ii) the presence of a distinct fast decay component in the case of ^3He. The ratio of overall trapping times (mean lifetimes against annihilation), R = T_{\\mathrm{trap}}(\\mbox{^{4}He})/T_{\\mathrm{trap}}(\\mbox{^{3}He}), has been determined to be 1.144 \\pm 0.009, which is in good agreement with a theoretical estimate yielding R = [(M^*(\\mbox{\\overline{\\mathrm{p}}}\\mbox{^{4}He})/ M^*(\\mbox{\\overline{ \\mathrm{p}}}\\mbox{^{3}He})]^2=1.14, where M^* denotes the reduced mass of the \\mbox{\\overline{\\mathrm{p}}}\\mbox{He^{++}}\\ system. The presence of a short-lived component with a lifetime of (0.154\\pm 0.007)\\ \\mbox{\\mus} in the case of \\mbox{^{3}He}\\ suggests that the \\mbox{\\overline{\\mathrm{p}}}\\mbox{^{3}He^{+}}\\ atom has a state of in...

  20. Single photon absorption by a single atom: from heralded absorption to polarization state mapping

    E-Print Network [OSTI]

    Nicolas Piro; Jürgen Eschner

    2015-02-19T23:59:59.000Z

    Together with photon emission, the absorption of a single photon by a single atom is a fundamental process in matter-light interaction that manifests its quantum mechanical nature. As an experimentally controlled process, it is a key tool for the realization of quantum technologies. In particular, in an atom/photon based quantum network scenario, in which localized atomic particles are used as quantum information processing nodes while photons are used as carriers of quantum information between distant nodes, controlling both emission and absorption of single photons by single atoms is required for quantum coherent state mapping between the two entities. Most experimental efforts to date have focused on establishing the control of single photon emission by single trapped atoms, and the implementation of quantum networking protocols using this interaction. In this chapter, we describe experimental efforts to control the process of single photon absorption by single trapped ions. We describe a series of experiments in which polarization entangled photon pairs, generated by a spontaneous parametric down-conversion source, are coupled to a single ion. First the source is operated to generate heralded single photons, and coincidences between the absorption event of one photon of the pair and the detection of the heralding partner photon are observed. We then show how polarization control in the process is established, leading to the manifestation of the photonic polarization entanglement in the absorption process. Finally, we introduce protocols in which this interaction scheme is harnessed to perform tasks in a quantum network, such as entanglement distribution among distant nodes of the network, and we demonstrate a specific protocol for heralded, high-fidelity photon-to-atom quantum state transfer.

  1. Trace Assessment for BWR ATWS Analysis

    SciTech Connect (OSTI)

    Cheng, L.Y.; Diamond, D.; Arantxa Cuadra, Gilad Raitses, Arnold Aronson

    2010-04-22T23:59:59.000Z

    A TRACE/PARCS input model has been developed in order to be able to analyze anticipated transients without scram (ATWS) in a boiling water reactor. The model is based on one developed previously for the Browns Ferry reactor for doing loss-of-coolant accident analysis. This model was updated by adding the control systems needed for ATWS and a core model using PARCS. The control systems were based on models previously developed for the TRAC-B code. The PARCS model is based on information (e.g., exposure and moderator density (void) history distributions) obtained from General Electric Hitachi and cross sections for GE14 fuel obtained from an independent source. The model is able to calculate an ATWS, initiated by the closure of main steam isolation valves, with recirculation pump trip, water level control, injection of borated water from the standby liquid control system and actuation of the automatic depres-surization system. The model is not considered complete and recommendations are made on how it should be improved.

  2. The MOTion trap: a hybrid atom-ion trap system for experiments in cold-chemistry and the production of cold polar molecular ions

    E-Print Network [OSTI]

    Sullivan, Scott Trevor

    2013-01-01T23:59:59.000Z

    specie- speci?c cooling techniques, producing molecular ionsextending laser cooling techniques to diatomic molecules [a more general cooling technique is highly desirable. One

  3. The MOTion trap: a hybrid atom-ion trap system for experiments in cold-chemistry and the production of cold polar molecular ions

    E-Print Network [OSTI]

    Sullivan, Scott Trevor

    2013-01-01T23:59:59.000Z

    interaction in the hybrid system, the self heating rate ismass dependent heating e?ects for the hybrid system of this

  4. Bogoliubov theory and bosonic atoms

    E-Print Network [OSTI]

    Phan Thanh Nam

    2011-09-13T23:59:59.000Z

    We formulate the Bogoliubov variational principle in a mathematical framework similar to the generalized Hartree-Fock theory. Then we analyze the Bogoliubov theory for bosonic atoms in details. We discuss heuristically why the Bogoliubov energy should give the first correction to the leading energy of large bosonic atoms.

  5. Trace elements in oil shale. Progress report, 1979-1980

    SciTech Connect (OSTI)

    Chappell, W R

    1980-01-01T23:59:59.000Z

    The purpose of this research program is to understand the potential impact of an oil shale industry on environmental levels of trace contaminants in the region. The program involves a comprehensive study of the sources, release mechanisms, transport, fate, and effects of toxic trace chemicals, principally the trace elements, in an oil shale industry. The overall objective of the program is to evaluate the environmental and health consequences of the release of toxic trace elements by shale and oil production and use. The baseline geochemical survey shows that stable trace elements maps can be constructed for numerous elements and that the trends observed are related to geologic and climatic factors. Shale retorted by above-ground processes tends to be very homogeneous (both in space and in time) in trace element content. Leachate studies show that significant amounts of B, F, and Mo are released from retorted shales and while B and Mo are rapidly flushed out, F is not. On the other hand, As, Se, and most other trace elements are not present in significant quantities. Significant amounts of F and B are also found in leachates of raw shales. Very large concentrations of reduced sulfur species are found in leachates of processed shale. Very high levels of B and Mo are taken up in some plants growing on processed shale with and without soil cover. There is a tendency for some trace elements to associate with specific organic fractions, indicating that organic chelation or complexation may play an important role. Many of the so-called standard methods for analyzing trace elements in oil shale-related materials are inadequate. A sampling manual is being written for the environmental scientist and practicing engineer. A new combination of methods is developed for separating the minerals in oil shale into different density fractions. Microbial investigations have tentatively identified the existence of thiobacilli in oil shale materials such as leachates. (DC)

  6. In-situ control system for atomization

    DOE Patents [OSTI]

    Anderson, I.E.; Figliola, R.S.; Terpstra, R.L.

    1995-06-13T23:59:59.000Z

    Melt atomizing apparatus comprising a melt supply orifice for supplying the melt for atomization and gas supply orifices proximate the melt supply orifice for supplying atomizing gas to atomize the melt as an atomization spray is disclosed. The apparatus includes a sensor, such as an optical and/or audio sensor, for providing atomization spray data, and a control unit responsive to the sensed atomization spray data for controlling at least one of the atomizing gas pressure and an actuator to adjust the relative position of the gas supply orifice and melt supply in a manner to achieve a desired atomization spray. 3 figs.

  7. Spectral Emission of Moving Atom

    E-Print Network [OSTI]

    J. X. Zheng-Johansson

    2008-03-17T23:59:59.000Z

    A renewed analysis of the H.E. Ives and G.R. Stilwell's experiment on moving hydrogen canal rays (J. Opt. Soc. Am., 1938, v.28, 215) concludes that the spectral emission of a moving atom exhibits always a redshift which informs not the direction of the atom's motion. The conclusion is also evident from a simple energy relation: atomic spectral radiation is emitted as an orbiting electron consumes a portion of its internal energy on transiting to a lower-energy state which however has in a moving atom an additional energy gain; this results in a redshift in the emission frequency. Based on auxiliary experimental information and a scheme for de Broglie particle formation, we give a vigorous elucidation of the mechanism for deceleration radiation of atomic electron; the corresponding prediction of the redshift is in complete agreement with the Ives and Stilwell's experimental formula.

  8. Redistribution of trace chemical species by a small convective cloud

    SciTech Connect (OSTI)

    Stith, J.L.; Alkezweeny, A.J.; Pleim, J.E.; Ching, J.K.S.

    1993-01-01T23:59:59.000Z

    The paper describes a new experiment with a SF6 tracer to determine the mixing history of a small region of cloud-base air. In situ measurements of the SF6 are made to follow the region and simultaneous measurements of natural trace gases are used to determine the dilution of the tagged region as it is affected by the cloud. After describing the experimental method, the results from an experiment with a small cumulus, which was ideally suited for the experiment, are explained. The goal of the paper is to better understand how convective clouds redistribute trace constituents (e.g. moisture, trace gases) in the vertical.

  9. Algorithms and analysis for underwater vehicle plume tracing.

    SciTech Connect (OSTI)

    Byrne, Raymond Harry; Savage, Elizabeth L. (Texas A& M University, College Station, TX); Hurtado, John Edward (Texas A& M University, College Station, TX); Eskridge, Steven E.

    2003-07-01T23:59:59.000Z

    The goal of this research was to develop and demonstrate cooperative 3-D plume tracing algorithms for miniature autonomous underwater vehicles. Applications for this technology include Lost Asset and Survivor Location Systems (L-SALS) and Ship-in-Port Patrol and Protection (SP3). This research was a joint effort that included Nekton Research, LLC, Sandia National Laboratories, and Texas A&M University. Nekton Research developed the miniature autonomous underwater vehicles while Sandia and Texas A&M developed the 3-D plume tracing algorithms. This report describes the plume tracing algorithm and presents test results from successful underwater testing with pseudo-plume sources.

  10. Supersonic coal water slurry fuel atomizer

    DOE Patents [OSTI]

    Becker, Frederick E. (Reading, MA); Smolensky, Leo A. (Concord, MA); Balsavich, John (Foxborough, MA)

    1991-01-01T23:59:59.000Z

    A supersonic coal water slurry atomizer utilizing supersonic gas velocities to atomize coal water slurry is provided wherein atomization occurs externally of the atomizer. The atomizer has a central tube defining a coal water slurry passageway surrounded by an annular sleeve defining an annular passageway for gas. A converging/diverging section is provided for accelerating gas in the annular passageway to supersonic velocities.

  11. A passive measurement of dissociated atom densities in atmospheric pressure air discharge plasmas using vacuum ultraviolet self-absorption spectroscopy

    SciTech Connect (OSTI)

    Laity, George [Center for Pulsed Power and Power Electronics, Department of Electrical and Computer Engineering and Department of Physics, Texas Tech University, Lubbock, Texas 79409 (United States); Applied Science and Technology Maturation Department, Sandia National Laboratories, Albuquerque, New Mexico 87123 (United States); Fierro, Andrew; Dickens, James; Neuber, Andreas [Center for Pulsed Power and Power Electronics, Department of Electrical and Computer Engineering and Department of Physics, Texas Tech University, Lubbock, Texas 79409 (United States); Frank, Klaus [Erlangen Centre for Astroparticle Physics, Department of Physics, Friedrich–Alexander University at Erlangen-Nürnberg, 91058 Erlangen (Germany)

    2014-03-28T23:59:59.000Z

    We demonstrate a method for determining the dissociation degree of atmospheric pressure air discharges by measuring the self-absorption characteristics of vacuum ultraviolet radiation from O and N atoms in the plasma. The atom densities are determined by modeling the amount of radiation trapping present in the discharge, without the use of typical optical absorption diagnostic techniques which require external sources of probing radiation into the experiment. For an 8.0?mm spark discharge between needle electrodes at atmospheric pressure, typical peak O atom densities of 8.5?×?10{sup 17}?cm{sup ?3} and peak N atom densities of 9.9?×?10{sup 17}?cm{sup ?3} are observed within the first ?1.0?mm of plasma near the anode tip by analyzing the OI and NI transitions in the 130.0–132.0?nm band of the vacuum ultraviolet spectrum.

  12. A self-injected, diode-pumped, solid-state ring laser for laser cooling of Li atoms

    E-Print Network [OSTI]

    Miake, Yudai; O'Hara, Kenneth M; Gensemer, Stephen

    2015-01-01T23:59:59.000Z

    We have constructed a solid-state light source for experiments with laser cooled lithium atoms based on a Nd:YVO$_4$ ring laser with second-harmonic generation. Unidirectional lasing, an improved mode selection, and a high output power of the ring laser was achieved by weak coupling to an external cavity which contained the lossy elements required for single frequency operation. Continuous frequency tuning is accomplished by controlling two PZTs in the internal and the external cavities simultaneously. The light source has been utilized to trap and cool fermionic lithium atoms into the quantum degenerate regime.

  13. 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.

  14. 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.

  15. 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.; Galatà, A.; De Lazzari, M.; Porcellato, A. M.; Roncolato, C.; Stark, S. [INFN-LNL, viale dell’Università 2, 35020 Legnaro (Italy)] [INFN-LNL, viale dell’Università 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.; Romé, M. [INFN Sezione di Milano and Dipartimento di Fisica, Università degli Studi di Milano, via Celoria 16, 20133 Milano (Italy)] [INFN Sezione di Milano and Dipartimento di Fisica, Università 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.

  16. 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.

  17. Calculation of geometric phases in electric dipole searches with trapped spin-1/2 particles based on direct solution of the Schrödinger equation

    E-Print Network [OSTI]

    A. Steyerl; C. Kaufman; G. Müller; S. S. Malik; A. M. Desai; R. Golub

    2014-05-23T23:59:59.000Z

    Pendlebury $\\textit{et al.}$ [Phys. Rev. A $\\textbf{70}$, 032102 (2004)] were the first to investigate the role of geometric phases in searches for an electric dipole moment (EDM) of elementary particles based on Ramsey-separated oscillatory field magnetic resonance with trapped ultracold neutrons and comagnetometer atoms. Their work was based on the Bloch equation and later work using the density matrix corroborated the results and extended the scope to describe the dynamics of spins in general fields and in bounded geometries. We solve the Schr\\"odinger equation directly for cylindrical trap geometry and obtain a full description of EDM-relevant spin behavior in general fields, including the short-time transients and vertical spin oscillation in the entire range of particle velocities. We apply this method to general macroscopic fields and to the field of a microscopic magnetic dipole.

  18. First-principles study on the interaction of nitrogen atom with ?–uranium: From surface adsorption to bulk diffusion

    SciTech Connect (OSTI)

    Su, Qiulei; Deng, Huiqiu, E-mail: hqdeng@hnu.edu.cn, E-mail: hqdeng@gmail.com; Xiao, Shifang; Li, Xiaofan; Hu, Wangyu [Department of Applied Physics, Hunan University, Changsha 410082 (China); Ao, Bingyun; Chen, Piheng [Science and Technology on Surface Physics and Chemistry Laboratory, P.O. Box 718-35, Mianyang 621907 (China)

    2014-04-28T23:59:59.000Z

    Experimental studies of nitriding on uranium surfaces show that the modified layers provide considerable protection against air corrosion. The bimodal distribution of nitrogen is affected by both its implantation and diffusion, and the diffusion of nitrogen during implantation is also governed by vacancy trapping. In the present paper, nitrogen adsorption, absorption, diffusion, and vacancy trapping on the surface of and in the bulk of ?–uranium are studied with a first-principles density functional theory approach and the climbing image nudged elastic band method. The calculated results indicate that, regardless of the nitrogen coverage, a nitrogen atom prefers to reside at the hollow1 site and octahedral (Oct) site on and below the surface, respectively. The lowest energy barriers for on-surface and penetration diffusion occur at a coverage of 1/2 monolayer. A nitrogen atom prefers to occupy the Oct site in bulk ?–uranium. High energy barriers are observed during the diffusion between neighboring Oct sites. A vacancy can capture its nearby interstitial nitrogen atom with a low energy barrier, providing a significant attractive nitrogen-vacancy interaction at the trapping center site. This study provides a reference for understanding the nitriding process on uranium surfaces.

  19. Sodium storage facility trace heat system design description

    SciTech Connect (OSTI)

    Jones, D.D.

    1997-06-12T23:59:59.000Z

    This document describes the SSF PLC Ladder Logic, Cross references, and the software that was used to control the amount of power applied to the SSF Trace Heated components.

  20. L-?Functions and Trace Formula Workshop Schedule

    E-Print Network [OSTI]

    2015-05-11T23:59:59.000Z

    L-?Functions and Trace Formula Workshop Schedule. May 11 – May 13, 2015 at Purdue University. Monday, May 11. 9:15 am – 9:30 am: Casselman/Shahidi:.