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Sample records for trap atoms atom

  1. Fundamental Electroweak Studies using Trapped Ions & Atoms

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

    collaboration performs fundamental electroweak studies on trapped ions & atoms. We use neutral atom and ion trapping techniques at radioactive ion beam facilities here and...

  2. Analysis of a magnetically trapped atom clock

    SciTech Connect (OSTI)

    Kadio, D.; Band, Y. B.

    2006-11-15

    We consider optimization of a rubidium atom clock that uses magnetically trapped Bose condensed atoms in a highly elongated trap, and determine the optimal conditions for minimum Allan variance of the clock using microwave Ramsey fringe spectroscopy. Elimination of magnetic field shifts and collisional shifts are considered. The effects of spin-dipolar relaxation are addressed in the optimization of the clock. We find that for the interstate interaction strength equal to or larger than the intrastate interaction strengths, a modulational instability results in phase separation and symmetry breaking of the two-component condensate composed of the ground and excited hyperfine clock levels, and this mechanism limits the clock accuracy.

  3. Polarization-dependent atomic dipole traps behind a circular aperture for neutral-atom quantum computing

    SciTech Connect (OSTI)

    Gillen-Christandl, Katharina; Copsey, Bert D.

    2011-02-15

    The neutral-atom quantum computing community has successfully implemented almost all necessary steps for constructing a neutral-atom quantum computer. We present computational results of a study aimed at solving the remaining problem of creating a quantum memory with individually addressable sites for quantum computing. The basis of this quantum memory is the diffraction pattern formed by laser light incident on a circular aperture. Very close to the aperture, the diffraction pattern has localized bright and dark spots that can serve as red-detuned or blue-detuned atomic dipole traps. These traps are suitable for quantum computing even for moderate laser powers. In particular, for moderate laser intensities ({approx}100 W/cm{sup 2}) and comparatively small detunings ({approx}1000-10 000 linewidths), trap depths of {approx}1 mK and trap frequencies of several to tens of kilohertz are achieved. Our results indicate that these dipole traps can be moved by tilting the incident laser beams without significantly changing the trap properties. We also explored the polarization dependence of these dipole traps. We developed a code that calculates the trapping potential energy for any magnetic substate of any hyperfine ground state of any alkali-metal atom for any laser detuning much smaller than the fine-structure splitting for any given electric field distribution. We describe details of our calculations and include a summary of different notations and conventions for the reduced matrix element and how to convert it to SI units. We applied this code to these traps and found a method for bringing two traps together and apart controllably without expelling the atoms from the trap and without significant tunneling probability between the traps. This approach can be scaled up to a two-dimensional array of many pinholes, forming a quantum memory with single-site addressability, in which pairs of atoms can be brought together and apart for two-qubit gates for quantum computing.

  4. Optical lattice clock with atoms confined in a shallow trap

    SciTech Connect (OSTI)

    Lemonde, Pierre; Wolf, Peter

    2005-09-15

    We study the trap depth requirement for the realization of an optical clock using atoms confined in a lattice. We show that site-to-site tunneling leads to a residual sensitivity to the atom dynamics hence requiring large depths [(50-100)E{sub r} for Sr] to avoid any frequency shift or line broadening of the atomic transition at the 10{sup -17}-10{sup -18} level. Such large depths and the corresponding laser power may, however, lead to difficulties (e.g., higher-order light shifts, two-photon ionization, technical difficulties) and therefore one would like to operate the clock in much shallower traps. To circumvent this problem we propose the use of an accelerated lattice. Acceleration lifts the degeneracy between adjacents potential wells which strongly inhibits tunneling. We show that using the Earth's gravity, much shallower traps (down to 5E{sub r} for Sr) can be used for the same accuracy goal.

  5. Atomic clock based on transient coherent population trapping

    SciTech Connect (OSTI)

    Guo Tao; Deng Ke; Chen Xuzong; Wang Zhong

    2009-04-13

    We proposed a scheme to implement coherent population trapping (CPT) atomic clock based on the transient CPT phenomenon. We proved that the transient transmitted laser power in a typical {lambda} system near CPT resonance features as a damping oscillation. Also, the oscillating frequency is exactly equal to the frequency detuning from the atomic hyperfine splitting. Therefore, we can directly measure the frequency detuning and then compensated to the output frequency of microwave oscillator to get the standard frequency. By this method, we can further simplify the structure of CPT atomic clock, and make it easier to be digitized and miniaturized.

  6. Isotopic abundance in atom trap trace analysis

    DOE Patents [OSTI]

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

    2014-03-18

    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.

  7. Theory of magic optical traps for Zeeman-insensitive clock transitions in alkali-metal atoms

    SciTech Connect (OSTI)

    Derevianko, Andrei

    2010-05-15

    Precision measurements and quantum-information processing with cold atoms may benefit from trapping atoms with specially engineered, 'magic' optical fields. At the magic trapping conditions, the relevant atomic properties remain immune to strong perturbations by the trapping fields. Here we develop a theoretical analysis of magic trapping for especially valuable Zeeman-insensitive clock transitions in alkali-metal atoms. The involved mechanism relies on applying a magic bias B field along a circularly polarized trapping laser field. We map out these B fields as a function of trapping laser wavelength for all commonly used alkalis. We also highlight a common error in evaluating Stark shifts of hyperfine manifolds.

  8. Simultaneous magneto-optical trapping of bosonic and fermionic chromium atoms

    SciTech Connect (OSTI)

    Chicireanu, R.; Pouderous, A.; Barbe, R.; Laburthe-Tolra, B.; Marechal, E.; Vernac, L.; Keller, J.-C.; Gorceix, O.

    2006-05-15

    We report on magneto-optical trapping of fermionic {sup 53}Cr atoms. A Zeeman-slowed atomic beam provides loading rates up to 3x10{sup 6} s{sup -1}. We present systematic characterization of the magneto-optical trap (MOT). We obtain up to 5x10{sup 5} atoms in the steady-state MOT. The atoms radiatively decay from the excited P state into metastable D states, and, due to the large dipolar magnetic moment of chromium atoms in these states, they can remain magnetically trapped in the quadrupole field gradient of the MOT. We study the accumulation of metastable {sup 53}Cr atoms in this magnetic trap. We also report on the simultaneous magneto-optical trapping of bosonic {sup 52}Cr and fermionic {sup 53}Cr atoms. Finally, we characterize the light-assisted collision losses in this Bose-Fermi cold mixture.

  9. Steven Chu: Laser Cooling and Trapping of Atoms

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

    ... 100, Issue 18; May 2008 Top Additional Web Pages: Landmarks: Laser Cooling of Atoms, Physical Review Focus, April 2, 2008 Steven Chu: Uncovering the Secret Life of Molecules, ...

  10. Luther-Emery Phase and Atomic-Density Waves in a Trapped Fermion Gas

    SciTech Connect (OSTI)

    Gao Xianlong; Rizzi, M.; Polini, Marco; Tosi, M. P.; Fazio, Rosario; Campo, V. L. Jr.; Capelle, K.

    2007-01-19

    The Luther-Emery liquid is a state of matter that is predicted to occur in one-dimensional systems of interacting fermions and is characterized by a gapless charge spectrum and a gapped spin spectrum. In this Letter we discuss a realization of the Luther-Emery phase in a trapped cold-atom gas. We study by means of the density-matrix renormalization-group technique a two-component atomic Fermi gas with attractive interactions subject to parabolic trapping inside an optical lattice. We demonstrate how this system exhibits compound phases characterized by the coexistence of spin pairing and atomic-density waves. A smooth crossover occurs with increasing magnitude of the atom-atom attraction to a state in which tightly bound spin-singlet dimers occupy the center of the trap. The existence of atomic-density waves could be detected in the elastic contribution to the light-scattering diffraction pattern.

  11. Precision polarization measurements of atoms in a far-off-resonance optical dipole trap

    SciTech Connect (OSTI)

    Fang, F.; Vieira, D. J.; Zhao, X.

    2011-01-15

    Precision measurement of atomic and nuclear polarization is an essential step for beta-asymmetry measurement of radioactive atoms. In this paper, we report the polarization measurement of Rb atoms in an yttrium-aluminum-garnet (YAG) far-off-resonance optical dipole trap. We have prepared a cold cloud of polarized Rb atoms in the YAG dipole trap by optical pumping and achieved an initial nuclear polarization of up to 97.2(5)%. The initial atom distribution in different Zeeman levels is measured by using a combination of microwave excitation, laser pushing, and atomic retrap techniques. The nuclear-spin polarization is further purified to 99.2(2)% in 10 s and maintained above 99% because the two-body collision loss rate between atoms in mixed spin states is greater than the one-body trap loss rate. Systematic effects on the nuclear polarization, including the off-resonance Raman scattering, magnetic field gradient, and background gas collisions, are discussed.

  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.; Norte, Richard; Meenehan, Sen M.; Cohen, Justin D.; Painter, Oskar

    2014-03-17

    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. High Contrast Ramsey Fringes with Coherent-Population-Trapping Pulses in a Double Lambda Atomic System

    SciTech Connect (OSTI)

    Zanon, T.; Guerandel, S.; Clercq, E. de; Holleville, D.; Dimarcq, N.; Clairon, A. [SYRTE, Observatoire de Paris, 61 Avenue de l'Observatoire, 75014 Paris (France)

    2005-05-20

    We report the observation of Raman-Ramsey fringes using a double lambda scheme creating coherent population trapping in an atomic ensemble combined with pulsed optical radiations. The observation was made in a Cs vapor mixed with N{sub 2} buffer gas in a closed cell. The double lambda scheme is created with lin perpendicular lin polarized laser beams leading to higher contrast than the usual simple lambda scheme. The pulsed trapping technique leads to narrow fringe widths scaling as 1/(2T) with high contrasts which are no longer limited by the saturation effect. This technique operates in a different way from the classical Ramsey sequence: the signal is done by applying a long trapping pulse to prepare the atomic state superposition, and fringe detection is accomplished by optical transmission during a short second trapping pulse without any perturbation of the dark state.

  14. Clock transition for a future optical frequency standard with trapped atoms

    SciTech Connect (OSTI)

    Courtillot, Irene; Quessada, Audrey; Kovacich, Richard P.; Brusch, Anders; Kolker, Dmitri; Zondy, Jean-Jacques; Rovera, Giovanni D.; Lemonde, Pierre

    2003-09-01

    We report direct excitation of the strongly forbidden 5s{sup 2} {sup 1}S{sub 0}-5s5p {sup 3}P{sub 0} transition in {sup 87}Sr. Its frequency is 429 228 004 235(20) kHz. A resonant laser creates a small leak in a magneto-optical trap (MOT): atoms build up to the metastable {sup 3}P{sub 0} state and escape the trapping process, leading to a detectable decrease in the MOT fluorescence. This line has a natural width of 10{sup -3} Hz and can be used for a new generation of optical frequency standards using atoms trapped in a light-shift-free dipole trap.

  15. Characterization of a state-insensitive dipole trap for cesium atoms

    SciTech Connect (OSTI)

    Phoonthong, P.; Douglas, P.; Wickenbrock, A.; Renzoni, F.

    2010-07-15

    In this work we characterize a state-insensitive dipole trap for cold cesium atoms, as realized by tightly focusing a single running laser beam at the magic wavelength. The use of trapping light at the magic wavelength of 935.6 nm resulted in the same ac Stark shift for the {sup 6}S{sub 1/2} ground state and the {sup 6}P{sub 3/2} excited state. A complete characterization of the trap is given, which includes the dependence of the lifetime on the trap depth, an analysis of the important role played by a depumper beam, and a comparison with dipole trapping at different (nonmagic) wavelengths. In particular, we measured the differential light shift of the relevant optical transition as a function of the trapping light wavelength, and showed that it becomes zero at the magic wavelength. Our results are compared to previous realizations of state-insensitive dipole traps for cesium atoms. We also discuss the possible role of the state-insensitive trap, its limitations, and possible developments for the study of ground-state quantum coherence phenomena and related applications.

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

    SciTech Connect (OSTI)

    Zelener, B. B. Saakyan, S. A.; Sautenkov, V. A.; Manykin, E. A.; Zelener, B. V.; Fortov, V. E.

    2014-11-15

    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.

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

    Office of Science (SC) Website

    Atom Trap Trace Analysis at ANL Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Applications of Nuclear Science Applications of Nuclear Science Archives Small Business Innovation Research / Small Business Technology Transfer Funding Opportunities Nuclear Science Advisory Committee (NSAC) Community Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301)

  18. A highly miniaturized vacuum package for a trapped ion atomic clock

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

    Schwindt, Peter D. D.; Jau, Yuan-Yu; Partner, Heather; Casias, Adrian; Wagner, Adrian R.; Moorman, Matthew; Manginell, Ronald P.; Kellogg, James R.; Prestage, John D.

    2016-05-12

    We report on the development of a highly miniaturized vacuum package for use in an atomic clock utilizing trapped ytterbium-171 ions. The vacuum package is approximately 1 cm3 in size and contains a linear quadrupole RF Paul ion trap, miniature neutral Yb sources, and a non-evaporable getter pump. We describe the fabrication process for making the Yb sources and assembling the vacuum package. To prepare the vacuum package for ion trapping, it was evacuated, baked at a high temperature, and then back filled with a helium buffer gas. Once appropriate vacuum conditions were achieved in the package, the package wasmore » sealed with a copper pinch-off and was then pumped only by the non-evaporable getter. We demonstrated ion trapping in this vacuum package and the operation of an atomic clock, stabilizing a local oscillator to the 12.6 GHz hyperfine transition of 171Yb+. The fractional frequency stability of the clock was measured to be 2 × 10-11 / τ1/2.« less

  19. Performance of a prototype atomic clock based on lin parallel lin coherent population trapping resonances in Rb atomic vapor

    SciTech Connect (OSTI)

    Mikhailov, Eugeniy E.; Horrom, Travis; Belcher, Nathan; Novikova, Irina

    2010-03-15

    We report on the performance of the first table-top prototype atomic clock based on coherent population trapping (CPT) resonances with parallel linearly polarized optical fields (lin parallel lin configuration). Our apparatus uses a vertical-cavity surface-emitting laser (VCSEL) tuned to the D{sub 1} line of {sup 87}Rb with the current modulation at the {sup 87}Rb hyperfine frequency. We demonstrate cancellation of the first-order light shift by the proper choice of rf modulation power and further improve our prototype clock stability by optimizing the parameters of the microwave lock loop. Operating in these optimal conditions, we measured a short-term fractional frequency stability (Allan deviation) 2x10{sup -11}{tau}{sup -1/2} for observation times 1 s{<=}{tau}{<=}20 s. This value is limited by large VCSEL phase noise and environmental temperature fluctuation. Further improvements in frequency stability should be possible with an apparatus designed as a dedicated lin parallel lin CPT resonance clock with environmental impacts minimized.

  20. Dark soliton decay due to trap anharmonicity in atomic Bose-Einstein condensates

    SciTech Connect (OSTI)

    Parker, N. G.; Proukakis, N. P.; Adams, C. S.

    2010-03-15

    A number of recent experiments with nearly pure atomic Bose-Einstein condensates have confirmed the predicted dark soliton oscillations when under harmonic trapping. However, a dark soliton propagating in an inhomogeneous condensate has also been predicted to be unstable to the emission of sound waves. Although harmonic trapping supports an equilibrium between the coexisting soliton and sound, we show that the ensuing dynamics are sensitive to trap anharmonicities. Such anharmonicities can break the soliton-sound equilibrium and lead to the net decay of the soliton on a considerably shorter time scale than other dissipation mechanisms. Thus, we propose that small realistic modifications to existing experimental setups could enable the experimental observation of this decay channel.

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

    SciTech Connect (OSTI)

    Yang, Jing; Yun, Peter; Tian, Yuan; Tan, Bozhong; Gu, Sihong

    2014-03-07

    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.

  2. {sup 39}Ar Detection at the 10{sup -16} Isotopic Abundance Level with Atom Trap Trace Analysis

    SciTech Connect (OSTI)

    Jiang, W.; Williams, W.; Bailey, K.; O'Connor, T. P.; Mueller, P.; Davis, A. M.; Hu, S.-M.; Sun, Y. R.; Lu, Z.-T.; Purtschert, R.; Sturchio, N. C.

    2011-03-11

    Atom trap trace analysis, a laser-based atom counting method, has been applied to analyze atmospheric {sup 39}Ar (half-life=269 yr), a cosmogenic isotope with an isotopic abundance of 8x10{sup -16}. In addition to the superior selectivity demonstrated in this work, the counting rate and efficiency of atom trap trace analysis have been improved by 2 orders of magnitude over prior results. The significant applications of this new analytical capability lie in radioisotope dating of ice and water samples and in the development of dark matter detectors.

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

    SciTech Connect (OSTI)

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

    2010-07-09

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

  4. Scheme for generating the singlet state of three atoms trapped in distant cavities coupled by optical fibers

    SciTech Connect (OSTI)

    Wang, Dong-Yang; Wen, Jing-Ji; Bai, Cheng-Hua; Hu, Shi; Cui, Wen-Xue; Wang, Hong-Fu; Zhu, Ai-Dong; Zhang, Shou

    2015-09-15

    An effective scheme is proposed to generate the singlet state with three four-level atoms trapped in three distant cavities connected with each other by three optical fibers, respectively. After a series of appropriate atom–cavity interactions, which can be arbitrarily controlled via the selective pairing of Raman transitions and corresponding optical switches, a three-atom singlet state can be successfully generated. The influence of atomic spontaneous decay, photon leakage of cavities and optical fibers on the fidelity of the state is numerically simulated showing that the three-atom singlet state can be generated with high fidelity by choosing the experimental parameters appropriately.

  5. Coherent population trapping resonances at lower atomic levels of Doppler broadened optical lines

    SciTech Connect (OSTI)

    ?ahin, E; Hamid, R; elik, M; zen, G; Izmailov, A Ch

    2014-11-30

    We have detected and analysed narrow high-contrast coherent population trapping (CPT) resonances, which are induced in absorption of a weak monochromatic probe light beam by counterpropagating two-frequency pump radiation in a cell with rarefied caesium vapour. The experimental investigations have been performed by the example of nonclosed three level ?-systems formed by spectral components of the D{sub 2} line of caesium atoms. The applied method allows one to analyse features of the CPT phenomenon directly at a given low long-lived level of the selected ?-system even in sufficiently complicated spectra of atomic gases with large Doppler broadening. We have established that CPT resonances in transmission of the probe beam exhibit not only a higher contrast but also a much lesser width in comparison with well- known CPT resonances in transmission of the corresponding two-frequency pump radiation. The results obtained can be used in selective photophysics, photochemistry and ultra-high resolution atomic (molecular) spectroscopy. (laser applications and other topics in quantum electronics)

  6. ATOM | NISAC

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

    NISACATOM content top Network Optimization Models (RNAS and ATOM) Posted by Admin on Mar 1, 2012 in | Comments 0 comments Many critical infrastructures can be represented by a...

  7. Reconfigurable site-selective manipulation of atomic quantum systems in two-dimensional arrays of dipole traps

    SciTech Connect (OSTI)

    Kruse, J.; Gierl, C.; Schlosser, M.; Birkl, G.

    2010-06-15

    We trap atoms in versatile two-dimensional (2D) arrays of optical potentials, prepare flexible 2D spin configurations, perform site-selective coherent manipulation, and demonstrate the implementation of simultaneous measurements of different system properties, such as dephasing and decoherence. This approach for the flexible manipulation of atomic quantum systems is based on the combination of 2D arrays of microlenses and 2D arrays of liquid crystal light modulators. This offers extended types of control for the investigation of quantum degenerate gases, quantum information processing, and quantum simulations.

  8. 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)

    2013-04-15

    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.

  9. Atom Interferometry

    ScienceCinema (OSTI)

    Mark Kasevich

    2010-01-08

    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?

  10. Atom Interferometry

    SciTech Connect (OSTI)

    Mark Kasevich

    2008-05-07

    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?

  11. Ultracold Atoms: How Quantum Field Theory Invaded Atomic Physics

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

    Ultracold Atoms: How Quantum Field Theory Invaded Atomic Physics Eric Braaten Ohio State University May 6, 2015 4:00 p.m. (coffee @ 3:30) The development of the technology for trapping atoms and cooling them to ultralow temperatures gave birth to a new subfield of atomic physics. It also led to the introduction of new theoretical methods into atomic physics, I n particular quantum field theory (QFT). Methods of QFT developed in high energy physics have proved to be very useful in ultracold atom

  12. 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.

    2011-01-15

    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.

  13. Collective mode evidence of high-spin bosonization in a trapped one-dimensional atomic Fermi gas with tunable spin

    SciTech Connect (OSTI)

    Liu, Xia-Ji Hu, Hui

    2014-11-15

    We calculate the frequency of collective modes of a one-dimensional repulsively interacting Fermi gas with high-spin symmetry confined in harmonic traps at zero temperature. This is a system realizable with fermionic alkaline-earth-metal atoms such as {sup 173}Yb, which displays an exact SU(?) spin symmetry with ??2 and behaves like a spinless interacting Bose gas in the limit of infinite spin components ???, namely high-spin bosonization. We solve the homogeneous equation of state of the high-spin Fermi system by using Bethe ansatz technique and obtain the density distribution in harmonic traps based on local density approximation. The frequency of collective modes is calculated by exactly solving the zero-temperature hydrodynamic equation. In the limit of large number of spin-components, we show that the mode frequency of the system approaches that of a one-dimensional spinless interacting Bose gas, as a result of high-spin bosonization. Our prediction of collective modes is in excellent agreement with a very recent measurement for a Fermi gas of {sup 173}Yb atoms with tunable spin confined in a two-dimensional tight optical lattice.

  14. Quantum and Classical Description of H Atom Under Magnetic Field and Quadrupole Trap Potential

    SciTech Connect (OSTI)

    Mahecha, J. [Institute of Physics, University of Antioquia, AA 1226, Medellin (Colombia); LPMC, Institute of Physics, University Paul Verlaine, 1 Bv Arago, 57078 Metz Cedex 3 (France); Salas, J. P. [Area of Applied Physics, University of La Rioja, C/Madre de Dios 51, 26006, Logrono (Spain)

    2006-12-01

    A discussion regarding the energy levels spectrum of quantum systems whose classical analogous has states of chaotic motion is presented. The chaotic dynamics of the classical underlying system has its manifestation in the wave functions (in the form of 'scars') and in the energy levels (in the form of 'statistical repulsion' of the energy levels). The above mentioned signatures are named 'quantum chaos'. A typical study of quantum chaos requires finding accurate energy eigenvalues of highly excited states, to calculate the nearest neighbors spacing between levels, to perform the 'unfolding' of the spectrum in order to separate the fluctuations, and finally to find the probability distribution of the unfolded spectrum. This is exemplified by the hydrogen atom under uniform magnetic field and a quadrupole electric field.

  15. Atomic magnetometer

    DOE Patents [OSTI]

    Schwindt, Peter; Johnson, Cort N.

    2012-07-03

    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.

  16. Atomic Chemistry in Turbulent Media I: Effect of Atomic Cooling...

    Office of Scientific and Technical Information (OSTI)

    Atomic Chemistry in Turbulent Media I: Effect of Atomic Cooling Citation Details In-Document Search Title: Atomic Chemistry in Turbulent Media I: Effect of Atomic Cooling Authors: ...

  17. Atom Trajectory Viewer

    Energy Science and Technology Software Center (OSTI)

    2015-12-28

    Atom Trajectory Viewer is a visualization tool developed to enable interactive exploration of atomic trajectories and corresponding statistics in molecular dynamics.

  18. Atomizing nozzle and process

    DOE Patents [OSTI]

    Anderson, Iver E.; Figliola, Richard S.; Molnar, Holly M.

    1993-07-20

    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.

  19. Atomizing nozzle and process

    DOE Patents [OSTI]

    Anderson, Iver E.; Figliola, Richard S.; Molnar, Holly M.

    1992-06-30

    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.

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

    National Nuclear Security Administration (NNSA)

    Takes Over Responsibility for all Atomic Energy Programs Atomic Energy Commission Takes Over Responsibility for all Atomic Energy Program Washington, DC In accordance with the ...

  1. Laser spectroscopy of the 4s4p {sup 3}P{sub 2} - 4s3d {sup 1}D{sub 2} transition on magnetically trapped calcium atoms

    SciTech Connect (OSTI)

    Dammalapati, U.; Norris, I.; Burrows, C.; Riis, E.

    2011-06-15

    Laser excitation of the 4s4p {sup 3}P{sub 2} - 4s3d {sup 1}D{sub 2} transition in atomic calcium has been observed and the wavelength determined to 1530.5298(6) nm. The metastable 4s4p {sup 3}P{sub 2} atoms were magnetically trapped in the quadrupole magnetic field of a magneto-optical trap. This state represents the only ''loss'' channel for the calcium atoms when laser cooled on the 4s{sup 2} {sup 1}S{sub 0} - 4s4p {sup 1}P{sub 1} transition. A rate equation model shows that an order of magnitude more atoms are trapped in this state compared with those taking part in the main cooling cycle. Excitation of the {sup 3}P{sub 2} atoms back up to the 4s3d {sup 1}D{sub 2} state provides a means of accessing these atoms. Efficient repumping is achieved if the 1530-nm laser is used in conjunction with a 672-nm laser driving the 4s3d {sup 1}D{sub 2} - 4s5p {sup 1}P{sub 1} transition. In the present experiment, we detected about 4.5x10{sup 4} trapped {sup 3}P{sub 2} atoms, a relatively low atom density, and measured a lifetime of approximately 1 s, which is limited by background collisions.

  2. Atomic Energy Commission : Atomic Power at Shippingport - 1958 Educational Film

    SciTech Connect (OSTI)

    2013-02-02

    The United States Atomic Energy Commission & Westinghouse Electric Company take us on a tour of an atomic power station.

  3. PARTICLE ACCELERATORS; 74 ATOMIC AND MOLECULAR PHYSICS; ATOMS...

    Office of Scientific and Technical Information (OSTI)

    74 ATOMIC AND MOLECULAR PHYSICS; ATOMS; ELECTRONS; HELIUM; LIGHT SOURCES; RADIATIONS; STORAGE RINGS; SYNCHROTRONS SYNCHROTRON RADIATION SYNCHROTRONLIGHT SOURCES QUANTUM CHAOS...

  4. Atomic Energy Commission : Atomic Power at Shippingport - 1958 Educational Film

    ScienceCinema (OSTI)

    None

    2014-07-31

    The United States Atomic Energy Commission & Westinghouse Electric Company take us on a tour of an atomic power station.

  5. High data-rate atom interferometers through high recapture efficiency

    SciTech Connect (OSTI)

    Biedermann, Grant; Rakholia, Akash Vrijal; McGuinness, Hayden

    2015-01-27

    An inertial sensing system includes a magneto-optical trap (MOT) that traps atoms within a specified trapping region. The system also includes a cooling laser that cools the trapped atoms so that the atoms remain within the specified region for a specified amount of time. The system further includes a light-pulse atom interferometer (LPAI) that performs an interferometric interrogation of the atoms to determine phase changes in the atoms. The system includes a controller that controls the timing of MOT and cooling laser operations, and controls the timing of interferometric operations to substantially recapture the atoms in the specified trapping region. The system includes a processor that determines the amount inertial movement of the inertial sensing system based on the determined phase changes in the atoms. Also, a method of inertial sensing using this inertial sensing system includes recapture of atoms within the MOT following interferometric interrogation by the LPAI.

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

    National Nuclear Security Administration (NNSA)

    Programs | National Nuclear Security Administration | (NNSA) Takes Over Responsibility for all Atomic Energy Programs Atomic Energy Commission Takes Over Responsibility for all Atomic Energy Program Washington, DC In accordance with the Atomic Energy Act of 1946, all atomic energy activities are transferred to the newly created Atomic Energy Commission

  7. Metal atom oxidation laser

    DOE Patents [OSTI]

    Jensen, R.J.; Rice, W.W.; Beattie, W.H.

    1975-10-28

    A chemical laser which operates by formation of metal or carbon atoms and reaction of such atoms with a gaseous oxidizer in an optical resonant cavity is described. The lasing species are diatomic or polyatomic in nature and are readily produced by exchange or other abstraction reactions between the metal or carbon atoms and the oxidizer. The lasing molecules may be metal or carbon monohalides or monoxides. (auth)

  8. Metal atom oxidation laser

    DOE Patents [OSTI]

    Jensen, R.J.; Rice, W.W.; Beattie, W.H.

    1975-10-28

    A chemical laser which operates by formation of metal or carbon atoms and reaction of such atoms with a gaseous oxidizer in an optical resonant cavity is described. The lasing species are diatomic or polyatomic in nature and are readily produced by exchange or other abstraction reactions between the metal or carbon atoms and the oxidizer. The lasing molecules may be metal or carbon monohalides or monoxides.

  9. Improved graphite furnace atomizer

    DOE Patents [OSTI]

    Siemer, D.D.

    1983-05-18

    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.

  10. The Harnessed Atom

    Broader source: Energy.gov [DOE]

    The Harnessed Atom is a new middle school science, technology, engineering, and math (STEM) curriculum extension that focuses on nuclear science and energy. It offers teachers accurate, unbiased,...

  11. Coherent manipulation of atoms by copropagating laser beams

    SciTech Connect (OSTI)

    Ovchinnikov, Yuri B.

    2006-03-15

    Optical dipole traps and fractional Talbot optical lattices based on the interference between multiple copropagating laser beams are proposed. The variation of relative amplitudes and phases of the interfering light beams of these traps makes it possible to manipulate the spatial position of trapped atoms. Examples of spatial translation and splitting of atoms between a set of the interference traps are considered. The prospect of constructing all-light atom chips based on the proposed technique is presented.

  12. Modified Embedded Atom Method

    Energy Science and Technology Software Center (OSTI)

    2012-08-01

    Interatomic force and energy calculation subroutine to be used with the molecular dynamics simulation code LAMMPS (Ref a.). The code evaluated the total energy and atomic forces (energy gradient) according to a cubic spline-based variant (Ref b.) of the Modified Embedded Atom Method (MEAM) with a additional Stillinger-Weber (SW) contribution.

  13. High data rate atom interferometric device

    SciTech Connect (OSTI)

    Biedermann, Grant; McGuinness, Hayden James Evans; Rakholia, Akash

    2015-07-21

    A light-pulse atomic interferometry (LPAI) apparatus is provided. The LPAI apparatus comprises a vessel, two sets of magnetic coils configured to magnetically confine an atomic vapor in two respective magneto-optical traps (MOTs) within the vessel when activated, and an optical system configured to irradiate the atomic vapor within the vessel with laser radiation that, when suitably tuned, can launch atoms previously confined in each of the MOTs toward the other MOT. In embodiments, the magnetic coils are configured to produce a magnetic field that is non-zero at the midpoint between the traps. In embodiments, the time-of-flight of the launched atoms from one MOT to the other is 12 ms or less. In embodiments, the MOTs are situated approximately 36 mm apart. In embodiments, the apparatus is configured to activate the magnetic coils according to a particular temporal magnetic field gradient profile.

  14. CNEEC - Atomic Layer Deposition Tutorial by Stacey Bent

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

    Atomic Layer Deposition

  15. Atomizing nozzle and method

    DOE Patents [OSTI]

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

    2000-03-16

    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.

  16. Optical atomic magnetometer

    DOE Patents [OSTI]

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

    2013-11-19

    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.

  17. Metal atomization spray nozzle

    DOE Patents [OSTI]

    Huxford, T.J.

    1993-11-16

    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.

  18. Metal atomization spray nozzle

    DOE Patents [OSTI]

    Huxford, Theodore J.

    1993-01-01

    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.

  19. A high-overtone bulk acoustic wave resonator-oscillator-based 4.596 GHz frequency source: Application to a coherent population trapping Cs vapor cell atomic clock

    SciTech Connect (OSTI)

    Daugey, Thomas; Friedt, Jean-Michel; Martin, Gilles; Boudot, Rodolphe

    2015-11-15

    This article reports on the design and characterization of a high-overtone bulk acoustic wave resonator (HBAR)-oscillator-based 4.596 GHz frequency source. A 2.298 GHz signal, generated by an oscillator constructed around a thermally controlled two-port aluminum nitride-sapphire HBAR resonator with a Q-factor of 24 000 at 68 °C, is frequency multiplied by 2–4.596 GHz, half of the Cs atom clock frequency. The temperature coefficient of frequency of the HBAR is measured to be −23 ppm/ °C at 2.298 GHz. The measured phase noise of the 4.596 GHz source is −105 dB rad{sup 2}/Hz at 1 kHz offset and −150 dB rad{sup 2}/Hz at 100 kHz offset. The 4.596 GHz output signal is used as a local oscillator in a laboratory-prototype Cs microcell-based coherent population trapping atomic clock. The signal is stabilized onto the atomic transition frequency by tuning finely a voltage-controlled phase shifter implemented in the 2.298 GHz HBAR-oscillator loop, preventing the need for a high-power-consuming direct digital synthesis. The short-term fractional frequency stability of the free-running oscillator is 1.8 × 10{sup −9} at one second integration time. In locked regime, the latter is improved in a preliminary proof-of-concept experiment at the level of 6.6 × 10{sup −11} τ{sup −1/2} up to a few seconds and found to be limited by the signal-to-noise ratio of the detected CPT resonance.

  20. General Atomics (GA) | Princeton Plasma Physics Lab

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

    General Atomics (GA) Subscribe to RSS - General Atomics (GA) General Atomics Image: General Atomics (GA) The Scorpion's Strategy: "Catch and Subdue" Read more about The Scorpion's...

  1. The Harnessed Atom | Department of Energy

    Office of Environmental Management (EM)

    The Harnessed Atom The Harnessed Atom The Harnessed Atom The Harnessed Atom is a new middle school science, technology, engineering, and math (STEM) curriculum extension...

  2. Atomic vapor laser isotope separation

    SciTech Connect (OSTI)

    Stern, R.C.; Paisner, J.A.

    1986-08-15

    The atomic vapor laser isotope separation (AVLIS) process for the enrichment of uranium is evaluated. (AIP)

  3. Iowa Powder Atomization Technologies

    SciTech Connect (OSTI)

    2012-01-01

    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.

  4. Atomic Force Microscope

    SciTech Connect (OSTI)

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

    1988-12-01

    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.

  5. Iowa Powder Atomization Technologies

    ScienceCinema (OSTI)

    None

    2013-03-01

    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.

  6. INL Laboratory Scale Atomizer

    SciTech Connect (OSTI)

    C.R. Clark; G.C. Knighton; R.S. Fielding; N.P. Hallinan

    2010-01-01

    A laboratory scale atomizer has been built at the Idaho National Laboratory. This has proven useful for laboratory scale tests and has been used to fabricate fuel used in the RERTR miniplate experiments. This instrument evolved over time with various improvements being made ‘on the fly’ in a trial and error process.

  7. Lawrenciums ionization potential, atom by atom

    SciTech Connect (OSTI)

    Miller, Johanna L.

    2015-06-15

    Researchers in Japan have begun probing the atomic physics of elements that can be produced only in minute quantities.

  8. A microfabricated atomic clock

    SciTech Connect (OSTI)

    Knappe, Svenja; Shah, Vishal; Schwindt, Peter D.D.; Hollberg, Leo; Kitching, John; Liew, Li-Anne; Moreland, John

    2004-08-30

    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.

  9. ATOMIC ENERGY COMMISSION

    Office of Legacy Management (LM)

    ' ATOMIC ENERGY COMMISSION Frank K. Pittman, Director, bivisioa of Waste &&gement and s- portation, Headquarters j CONTAMItUTED RX-AEC-OWNED OR LEASED FACILITIES' This memorandum responds to your TWX certain information on the above subject. the documentation necessary to answer your available due to the records disposal vailing at the time of release or From records that are available and from disc&ions with most familiar with the transfer operations, &have the current

  10. Budget Atomization | Department of Energy

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

    Budget Atomization Budget Atomization Howard Dickenson, Deputy Associate Administrator for Acquisition and Project Management presented on Budget Atomization from the NNSA perspective. Howard presented an overview of the NNSA budget structure and an example of LANL controls. Chris Johns, Director of the Budget Office, DOE Office of the CFO presented on Budget Atomization from the DOE perspective. Chris provided an overview of funding, provided examples, and demonstrated the effect on labs/sites.

  11. Atomizer with liquid spray quenching

    DOE Patents [OSTI]

    Anderson, I.E.; Osborne, M.G.; Terpstra, R.L.

    1998-04-14

    Method and apparatus are disclosed for making metallic powder particles wherein a metallic melt is atomized by a rotating disk or other atomizer at an atomizing location in a manner to form molten droplets moving in a direction away from said atomizing location. The atomized droplets pass through a series of thin liquid quenching sheets disposed in succession about the atomizing location with each successive quenching sheet being at an increasing distance from the atomizing location. The atomized droplets are incrementally cooled and optionally passivated as they pass through the series of liquid quenching sheets without distorting the atomized droplets from their generally spherical shape. The atomized, cooled droplets can be received in a chamber having a collection wall disposed outwardly of the series of liquid quenching sheets. A liquid quenchant can be flowed proximate the chamber wall to carry the cooled atomized droplets to a collection chamber where atomized powder particles and the liquid quenchant are separated such that the liquid quenchant can be recycled. 6 figs.

  12. Atomizer with liquid spray quenching

    DOE Patents [OSTI]

    Anderson, Iver E.; Osborne, Matthew G.; Terpstra, Robert L.

    1998-04-14

    Method and apparatus for making metallic powder particles wherein a metallic melt is atomized by a rotating disk or other atomizer at an atomizing location in a manner to form molten droplets moving in a direction away from said atomizing location. The atomized droplets pass through a series of thin liquid quenching sheets disposed in succession about the atomizing location with each successive quenching sheet being at an increasing distance from the atomizing location. The atomized droplets are incrementally cooled and optionally passivated as they pass through the series of liquid quenching sheets without distorting the atomized droplets from their generally spherical shape. The atomized, cooled droplets can be received in a chamber having a collection wall disposed outwardly of the series of liquid quenching sheets. A liquid quenchant can be flowed proximate the chamber wall to carry the cooled atomized droplets to a collection chamber where atomized powder particles and the liquid quenchant are separated such that the liquid quenchant can be recycled.

  13. DOE - NNSA/NFO -- Atomic Testing Museum

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

    National Atomic Testing Museum NNSANFO Language Options U.S. DOENNSA - Nevada Field Office NATIONAL ATOMIC TESTING MUSEUM Photograph of Atomic Testing Museum The Nevada Test Site ...

  14. Atomic data for fusion

    SciTech Connect (OSTI)

    Hunter, H.T.; Kirkpatrick, M.I.; Alvarez, I.; Cisneros, C.; Phaneuf, R.A.; Barnett, C.F.

    1990-07-01

    This report provides a handbook of recommended cross-section and rate-coefficient data for inelastic collisions between hydrogen, helium and lithium atoms, molecules and ions, and encompasses more than 400 different reactions of primary interest in fusion research. Published experimental and theoretical data have been collected and evaluated, and the recommended data are presented in tabular, graphical and parametrized form. Processes include excitation and spectral line emission, charge exchange, ionization, stripping, dissociation and particle interchange reactions. The range of collision energies is appropriate to applications in fusion-energy research.

  15. Atomically resolved force microscopy at room temperature

    SciTech Connect (OSTI)

    Morita, Seizo

    2014-04-24

    Atomic force microscopy (AFM) can now not only image individual atoms but also construct atom letters using atom manipulation method even at room temperature (RT). Therefore, the AFM is the second generation atomic tool following the scanning tunneling microscopy (STM). However the AFM can image even insulating atoms, and also directly measure/map the atomic force and potential at the atomic scale. Noting these advantages, we have been developing a bottom-up nanostructuring system at RT based on the AFM. It can identify chemical species of individual atoms and then manipulate selected atom species to the predesigned site one-by-one to assemble complex nanostructures consisted of multi atom species at RT. Here we introduce our results toward atom-by-atom assembly of composite nanostructures based on the AFM at RT including the latest result on atom gating of nano-space for atom-by-atom creation of atom clusters at RT for semiconductor surfaces.

  16. Spectroscopy and isotope shifts of the 4s3d {sup 1}D{sub 2}-4s5p {sup 1}P{sub 1} repumping transition in magneto-optically trapped calcium atoms

    SciTech Connect (OSTI)

    Dammalapati, U.; Norris, I.; Burrows, C.; Arnold, A. S.; Riis, E.

    2010-02-15

    We investigate a repumping scheme for magneto-optically trapped calcium atoms. It is based on excitation of the 4s3d{sup 1}D{sub 2}-4s5p{sup 1}P{sub 1} transition at 672 nm with an extended cavity diode laser. The effect of the repumping is approximately a factor of three increase in trap lifetime and a doubling of the trapping efficiency from a Zeeman slowed thermal beam. Added to this, the 672-nm laser repumps atoms from an otherwise dark state to yield an overall increase in detected fluorescence signal from the magneto-optic trap (MOT) of more than an order of magnitude. Furthermore, we report isotope shift measurements of the 672-nm transition, for the first time, for four naturally occurring even isotopes. Using available charge radii data, the observed shifts, extending up to 4.3 GHz, display the expected linear dependence in a King plot analysis. The measured shifts are used to determine the isotope shifts of the remaining {sup 41,43,46}Ca isotopes. These might be of interest where less abundant isotopes are used enabling isotope selective repumping, resulting in enhanced trapping and detection efficiencies.

  17. 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.; Jervis, D.

    2014-04-15

    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.

  18. The Collective Atomic Recoil Laser

    SciTech Connect (OSTI)

    Courteille, Ph.W.; Cube, C. avon; Deh, B.; Kruse, D.; Ludewig, A.; Slama, S.; Zimmermann, C.

    2005-05-05

    An ensemble of periodically ordered atoms coherently scatters the light of an incident laser beam. The scattered and the incident light may interfere and give rise to a light intensity modulation and thus to optical dipole forces which, in turn, emphasize the atomic ordering. This positive feedback is at the origin of the collective atomic recoil laser (CARL). We demonstrate this dynamics using ultracold atoms confined by dipole forces in a unidirectionally pumped far red-detuned high-finesse optical ring cavity. Under the influence of an additional dissipative force exerted by an optical molasses the atoms, starting from an unordered distribution, spontaneously form a density grating moving at constant velocity. Additionally, steady state lasing is observed in the reverse direction if the pump laser power exceeds a certain threshold. We compare the dynamics of the atomic trajectories to the behavior of globally coupled oscillators, which exhibit phase transitions from incoherent to coherent states if the coupling strength exceeds a critical value.

  19. General Atomics | Open Energy Information

    Open Energy Info (EERE)

    Product: General Atomics offers research, development and consulting services to the nuclear industry, including nuclear energy production, manufacturing, defense and related...

  20. Scanning magnetoresistance microscopy of atom chips

    SciTech Connect (OSTI)

    Volk, M.; Whitlock, S.; Wolff, C. H.; Hall, B. V.; Sidorov, A. I.

    2008-02-15

    Surface based geometries of microfabricated wires or patterned magnetic films can be used to magnetically trap and manipulate ultracold neutral atoms or Bose-Einstein condensates. We investigate the magnetic properties of such atom chips using a scanning magnetoresistive (MR) microscope with high spatial resolution and high field sensitivity. By comparing MR scans of a permanent magnetic atom chip to field profiles obtained using ultracold atoms, we show that MR sensors are ideally suited to observe small variations of the magnetic field caused by imperfections in the wires or magnetic materials which ultimately lead to fragmentation of ultracold atom clouds. Measurements are also provided for the magnetic field produced by a thin current-carrying wire with small geometric modulations along the edge. Comparisons of our measurements with a full numeric calculation of the current flow in the wire and the subsequent magnetic field show excellent agreement. Our results highlight the use of scanning MR microscopy as a convenient and powerful technique for precisely characterizing the magnetic fields produced near the surface of atom chips.

  1. Atomic Scale Characterization of Compound Semiconductors Using Atom Probe Tomography

    SciTech Connect (OSTI)

    Gorman, B. P.; Norman, A. G.; Lawrence, D.; Prosa, T.; Guthrey, H.; Al-Jassim, M.

    2011-01-01

    Internal interfaces are critical in determining the performance of III-V multijunction solar cells. Studying these interfaces with atomic resolution using a combination of transmission electron microscopy (TEM), atom probe tomography (APT), and density functional calculations enables a more fundamental understanding of carrier dynamics in photovoltaic (PV) device structures. To achieve full atomic scale spatial and chemical resolution, data acquisition parameters in laser pulsed APT must be carefully studied to eliminate surface diffusion. Atom probe data with minimized group V ion clustering and expected stoichiometry can be achieved by adjusting laser pulse power, pulse repetition rate, and specimen preparation parameters such that heat flow away from the evaporating surface is maximized. Applying these improved analysis conditions to III-V based PV gives an atomic scale understanding of compositional and dopant profiles across interfaces and tunnel junctions and the initial stages of alloy clustering and dopant accumulation. Details on APT experimental methods and future in-situ instrumentation developments are illustrated.

  2. The Atomic City / The Magic of the Atom - 1950's Atomic Energy Commission Documentary

    ScienceCinema (OSTI)

    None

    2014-07-31

    The story of American cities located near atomic power plants, and steps taken monitoring radiation to ensure the safety of the public who live nearby. .

  3. The Atomic City / The Magic of the Atom - 1950's Atomic Energy Commission Documentary

    SciTech Connect (OSTI)

    2012-06-04

    The story of American cities located near atomic power plants, and steps taken monitoring radiation to ensure the safety of the public who live nearby. .

  4. Thirteenth International Conference on Atomic Physics(IGAP-13)

    SciTech Connect (OSTI)

    Walther, H.; Haensch, T.W.; Neizert, B. (eds.) (Max PlanckInstitute for Quantum Optics, Garching (Germany) Ludwig MaximilianUniversity, Munich (Germany))

    1993-01-01

    This conference proceeding contains invited papers on recentprogress in many subfields of atomic physics. Major advances inspectroscopy, laser cooling and trapping, atom interferometry,cavity quantum electrodynamics are discussed in many of thepresented papers. Quantum chaos is explored as well as novelexperiments with atoms in intense laser fields are discussed. Atotal of forty two papers are given in this proceedings, out ofthese, eleven have been abstracted for database. (AIP)

  5. In-situ control system for atomization

    DOE Patents [OSTI]

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

    1995-06-13

    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.

  6. In-situ control system for atomization

    DOE Patents [OSTI]

    Anderson, Iver E.; Figliola, Richard S.; Terpstra, Robert L.

    1995-06-13

    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. 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.

  7. Supersonic coal water slurry fuel atomizer

    DOE Patents [OSTI]

    Becker, Frederick E.; Smolensky, Leo A.; Balsavich, John

    1991-01-01

    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.

  8. Los Alamos National Laboratory ATOMIC PHOTOGRAPHY ATOMIC PHOTOGRAPHY

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

    ATOMIC PHOTOGRAPHY ATOMIC PHOTOGRAPHY BLASTS FROM THE PAST BLASTS FROM THE PAST Twenty-five U.S. atmospheric nuclear weapons operations (each a series of tests) were conducted from 1945 to 1963, primarily at the Pacific Proving Grounds and at the Nevada Test Site, southeastern Nevada. Below, observers witness Operation Greenhouse, Eniwetok Atoll, spring 1951. Greenhouse was a series of four tests. 17 Proof of principle for thermonuclear weapons, the 225-kiloton George test, May 8, 1951, of

  9. ATOMIC ENERGY ACT OF 1946

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

    D. Niisc AEC Hcadqoartcrs Library Voliiinc I Principal Docriiiiciits U.S. ATOMIC ENERGY COMMISSION WASHINGTON, 1965 PUBLIC LAW 5 8 5 - 7 9 CONQRESS CHAPTER 724-2 ...

  10. Imaging atoms in 3-D

    ScienceCinema (OSTI)

    Ercius, Peter

    2014-06-27

    Berkeley Lab's Peter Ercius discusses "Imaging atoms in 3-D" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas

  11. Efimov physics in cold atoms

    SciTech Connect (OSTI)

    Braaten, Eric . E-mail: braaten@mps.ohio-state.edu; Hammer, H.-W. . E-mail: hammer@itkp.uni-bonn.de

    2007-01-15

    Atoms with a large scattering length have universal low-energy properties that do not depend on the details of their structure or their interactions at short distances. In the 2-atom sector, the universal properties are familiar and depend only on the scattering length. In the 3-atom sector for identical bosons, the universal properties include the existence of a sequence of shallow triatomic molecules called Efimov trimers and log-periodic dependence of scattering observables on the energy and the scattering length. In this review, we summarize the universal results that are currently known. We also summarize the experimental information that is currently available with an emphasis on 3-atom loss processes.

  12. Theoretical studies of atomic transitions

    SciTech Connect (OSTI)

    Fischer, C.F.

    1990-10-01

    This paper discusses: lifetime of excited states; core-polarization studies; large relativistic calculations; Monte Carlo Hartree-Fock (MCHF) atomic structure package; and MCHF codes for the hypercube. (LSP)

  13. UNITED STATES ATOMIC ENERGY COMMISSION

    Office of Legacy Management (LM)

    I(S.0 -01: SPECIAL NUCLEAR MATERIAL LlCEWSE Pursuant to the Atomic Energy Act of 1954 and Title 10, Code of Federal Regulations, Chapter 1, Part 70, "Special Nuclear Material ...

  14. u. S. Atomic Energy Commission

    Office of Legacy Management (LM)

    S. Atomic Energy Commission R. 0. Box 30, Ansonia Station New York ES, N. Y. MATERIALS 5+k& hJf Reference: SK:BL Attention: Mr. R. J. Smith Jr. Director Special Materials Division ...

  15. Analysis of a free oscillation atom interferometer

    SciTech Connect (OSTI)

    Kafle, Rudra P.; Zozulya, Alex A.; Anderson, Dana Z.

    2011-09-15

    We analyze a Bose-Einstein condensate (BEC)-based free oscillation atom Michelson interferometer in a weakly confining harmonic magnetic trap. A BEC at the center of the trap is split into two harmonics by a laser standing wave. The harmonics move in opposite directions with equal speeds and turn back under the influence of the trapping potential at their classical turning points. The harmonics are allowed to pass through each other and a recombination pulse is applied when they overlap at the end of a cycle after they return for the second time. We derive an expression for the contrast of the interferometric fringes and obtain the fundamental limit of performance of the interferometer in the parameter space.

  16. Atomic vapor laser isotope separation process

    DOE Patents [OSTI]

    Wyeth, Richard W.; Paisner, Jeffrey A.; Story, Thomas

    1990-01-01

    A laser spectroscopy system is utilized in an atomic vapor laser isotope separation process. The system determines spectral components of an atomic vapor utilizing a laser heterodyne technique.

  17. Manhattan Project: Atomic Discoveries, 1890s-1939

    Office of Scientific and Technical Information (OSTI)

    The exact nature of these atoms remained elusive, however, despite centuries of attempts ... Explorations into the nature of the atom from 1919 to 1932 confirmed this new model, ...

  18. Atomic Photography: Blasts from the Past

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

    Atomic Photography National Security Science Latest Issue:July 2015 past issues All Issues submit Atomic Photography: Blasts from the Past A gallery of images reveals the weird...

  19. Quantum computations with atoms in optical lattices: Marker qubits and molecular interactions

    SciTech Connect (OSTI)

    Calarco, T.; Dorner, U.; Zoller, P.; Julienne, P.S.; Williams, C.J.

    2004-07-01

    We develop a scheme for quantum computation with neutral atoms, based on the concept of 'marker' atoms, i.e., auxiliary atoms that can be efficiently transported in state-independent periodic external traps to operate quantum gates between physically distant qubits. This allows for relaxing a number of experimental constraints for quantum computation with neutral atoms in microscopic potential, including single-atom laser addressability. We discuss the advantages of this approach in a concrete physical scenario involving molecular interactions.

  20. Atomic memory access hardware implementations

    SciTech Connect (OSTI)

    Ahn, Jung Ho; Erez, Mattan; Dally, William J

    2015-02-17

    Atomic memory access requests are handled using a variety of systems and methods. According to one example method, a data-processing circuit having an address-request generator that issues requests to a common memory implements a method of processing the requests using a memory-access intervention circuit coupled between the generator and the common memory. The method identifies a current atomic-memory access request from a plurality of memory access requests. A data set is stored that corresponds to the current atomic-memory access request in a data storage circuit within the intervention circuit. It is determined whether the current atomic-memory access request corresponds to at least one previously-stored atomic-memory access request. In response to determining correspondence, the current request is implemented by retrieving data from the common memory. The data is modified in response to the current request and at least one other access request in the memory-access intervention circuit.

  1. Atomizing, continuous, water monitoring module

    DOE Patents [OSTI]

    Thompson, C.V.; Wise, M.B.

    1997-07-08

    A system for continuously analyzing volatile constituents of a liquid is described. The system contains a pump for continuously pumping the liquid to be tested at a predetermined flow rate into an extracting container through a liquid directing tube having an orifice at one end and positioned to direct the liquid into the extracting container at a flow rate sufficient to atomize the liquid within the extracting container. A continuous supply of helium carrier gas at a predetermined flow rate is directed through a tube into the extracting container and co-mingled with the atomized liquid to extract the volatile constituents contained within the atomized liquid. The helium containing the extracted volatile constituents flows out of the extracting container into a mass spectrometer for an analysis of the volatile constituents of the liquid. 3 figs.

  2. Atomizing, continuous, water monitoring module

    DOE Patents [OSTI]

    Thompson, Cyril V.; Wise, Marcus B.

    1997-01-01

    A system for continuously analyzing volatile constituents of a liquid is described. The system contains a pump for continuously pumping the liquid to be tested at a predetermined flow rate into an extracting container through a liquid directing tube having an orifice at one end and positioned to direct the liquid into the extracting container at a flow rate sufficient to atomize the liquid within the extracting container. A continuous supply of helium carrier gas at a predetermined flow rate is directed through a tube into the extracting container and co-mingled with the atomized liquid to extract the volatile constituents contained within the atomized liquid. The helium containing the extracted volatile constituents flows out of the extracting container into a mass spectrometer for an analysis of the volatile constituents of the liquid.

  3. Hot atom chemistry and radiopharmaceuticals

    SciTech Connect (OSTI)

    Krohn, Kenneth A.; Moerlein, Stephen M.; Link, Jeanne M.; Welch, Michael J.

    2012-12-19

    The chemical products made in a cyclotron target are a combined result of the chemical effects of the nuclear transformation that made the radioactive atom and the bulk radiolysis in the target. This review uses some well-known examples to understand how hot atom chemistry explains the primary products from a nuclear reaction and then how radiation chemistry is exploited to set up the optimal product for radiosynthesis. It also addresses the chemical effects of nuclear decay. There are important principles that are common to hot atom chemistry and radiopharmaceutical chemistry. Both emphasize short-lived radionuclides and manipulation of high specific activity nuclides. Furthermore, they both rely on radiochromatographic separation for identification of no-carrieradded products.

  4. Atomic hydrogen in planetary nebulae

    SciTech Connect (OSTI)

    Schneider, S.E.; Silverglate, P.R.; Altschuler, D.R.; Giovanardi, C.

    1987-03-01

    The authors searched for neutral atomic hydrogen associated with 22 planetary nebulae and three evolved stars in the 21 cm line at the Arecibo Observatory. Objects whose radial velocities permitted discrimination from Galactic H I were chosen for observation. Hydrogen was detected in absorption from IC 4997. From the measurements new low limits are derived to the mass of atomic hydrogen associated with the undetected nebulae. Radio continuum observations were also made of several of the nebulae at 12.6 cm. The authors reexamine previous measurements of H I in planetary nebulae, and present the data on a consistent footing. The question of planetary nebula distances is considered at length. Finally, implications of the H I measurements for nebular evolution are discussed and it is suggested that atomic hydrogen seen in absorption was expelled from the progenitor star during the final 1000 yr prior to the onset of ionization. 68 references.

  5. Relativistic atomic beam spectroscopy II

    SciTech Connect (OSTI)

    1989-12-31

    The negative ion of H is one of the simplest 3-body atomic systems. The techniques we have developed for experimental study of atoms moving near speed of light have been productive. This proposal request continuing support for experimental studies of the H{sup -} system, principally at the 800 MeV linear accelerator (LAMPF) at Los Alamos. Four experiments are currently planned: photodetachment of H{sup -} near threshold in electric field, interaction of relativistic H{sup -} ions with matter, high excitations and double charge escape in H{sup -}, and multiphoton detachment of electrons from H{sup -}.

  6. Matrix isolation sublimation: An apparatus for producing cryogenic beams of atoms and molecules

    SciTech Connect (OSTI)

    Sacramento, R. L.; Alves, B. X.; Silva, B. A.; Wolff, W.; Cesar, C. L.; Oliveira, A. N.; Li, M. S.

    2015-07-15

    We describe the apparatus to generate cryogenic beams of atoms and molecules based on matrix isolation sublimation. Isolation matrices of Ne and H{sub 2} are hosts for atomic and molecular species which are sublimated into vacuum at cryogenic temperatures. The resulting cryogenic beams are used for high-resolution laser spectroscopy. The technique also aims at loading atomic and molecular traps.

  7. Displacement per Atom, Primary Knocked-on Atoms Produced in an Atomic Solid Target

    Energy Science and Technology Software Center (OSTI)

    2015-07-01

    Version 00 DART calculates the total number of displacements, primary knocked-on atoms, recoil spectra, displacement cross sections and displacement per atoms rates in a poly atomic solid target, composed of many different isotopes, using ENDF/B-VI derived cross sections. To calculate these values, different incident particles were considered: neutrons, ions and electrons. The user needs only to specify an incident particle energy spectrum and the composition of the target. The number of displaced atoms is calculatedmore » within the Binary Collision Approximation framework. To calculate the number of displacements the DART code does not use the classical NRT dpa analytical formula, which is only appropriate for projectile and target of the same mass. It numerically solves the linearized Boltzmann equation for a polyatomic target. It can be a useful tool to select the nature and energy of ions or electrons in particle accelerators or electron microscopes to mimic the primary damage induced by neutron irradiation in nuclear plants or fission facilities. Nuclear data: • Typically any ENDFB format evaluation may be used. This package includes the ENDFB-VI nuclear data library. Energy ranges: • Neutron or ion : 10E-11 to 20 MeV Data library distributed with DART v1.0: • ENDFB-VI nuclear data library« less

  8. Atomic vapor laser isotope separation

    SciTech Connect (OSTI)

    Stern, R.C.; Paisner, J.A.

    1985-11-08

    Atomic vapor laser isotope separation (AVLIS) is a general and powerful technique. A major present application to the enrichment of uranium for light-water power reactor fuel has been under development for over 10 years. In June 1985 the Department of Energy announced the selection of AVLIS as the technology to meet the nation's future need for the internationally competitive production of uranium separative work. The economic basis for this decision is considered, with an indicated of the constraints placed on the process figures of merit and the process laser system. We then trace an atom through a generic AVLIS separator and give examples of the physical steps encountered, the models used to describe the process physics, the fundamental parameters involved, and the role of diagnostic laser measurements.

  9. The Modified Embedded Atom Method

    SciTech Connect (OSTI)

    Baskes, M.I.

    1994-08-01

    Recent modifications have been made to generalize the Embedded Atom Method (EAM) to describe bonding in diverse materials. By including angular dependence of the electron density in an empirical way, the Modified Embedded Atom Method (MEAM) has been able to reproduce the basic energetic and structural properties of 45 elements. This method is ideally suited for examining the interfacial behavior of dissimilar materials. This paper explains in detail the derivation of the method, shows how the parameters of the MEAM are determined directly from experiment or first principles calculations, and examines the quality of the reproduction of the database. Materials with fcc, bcc, hcp, and diamond cubic crystal structure are discussed. A few simple examples of the application of the MEAM to surfaces and interfaces are presented. Calculations of pullout of a SiC fiber in a diamond matrix as a function of applied stress show non-uniform deformation of the fiber.

  10. The Future of Atomic Energy

    DOE R&D Accomplishments [OSTI]

    Fermi, E.

    1946-05-27

    There is definitely a technical possibility that atomic power may gradually develop into one of the principal sources of useful power. If this expectation will prove correct, great advantages can be expected to come from the fact that the weight of the fuel is almost negligible. This feature may be particularly valuable for making power available to regions of difficult access and far from deposits of coal. It also may prove a great asset in mobile power units for example in a power plant for ship propulsion. On the negative side there are some technical limitations to be applicability of atomic power of which perhaps the most serious is the impossibility of constructing light power units; also there will be some peculiar difficulties in operating atomic plants, as for example the necessity of handling highly radioactive substances which will necessitate, at least for some considerable period, the use of specially skilled personnel for the operation. But the chief obstacle in the way of developing atomic power will be the difficulty of organizing a large scale industrial development in an internationally safe way. This presents actually problems much more difficult to solve than any of the technical developments that are necessary, It will require an unusual amount of statesmanship to balance properly the necessity of allaying the international suspicion that arises from withholding technical secrets against the obvious danger of dumping the details of the procedures for an extremely dangerous new method of warfare on a world that may not yet be prepared to renounce war. Furthermore, the proper balance should be found in the relatively short time that will elapse before the 'secrets' will naturally become open knowledge by rediscovery on part of the scientists and engineers of other countries.

  11. Atomic vapor laser isotope separation process

    DOE Patents [OSTI]

    Wyeth, R.W.; Paisner, J.A.; Story, T.

    1990-08-21

    A laser spectroscopy system is utilized in an atomic vapor laser isotope separation process. The system determines spectral components of an atomic vapor utilizing a laser heterodyne technique. 23 figs.

  12. Princeton Plasma Physics Lab - General Atomics (GA)

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

    general-atomics-ga General Atomics en The Scorpion's Strategy: "Catch and Subdue" http:www.pppl.govnode1132

  13. Controlling dipole-dipole frequency shifts in a lattice-based optical atomic clock

    SciTech Connect (OSTI)

    Chang, D.E.; Lukin, M.D.; Ye Jun

    2004-02-01

    Motivated by the ideas of using cold alkaline-earth atoms trapped in an optical lattice for realization of optical atomic clocks, we investigate theoretically the perturbative effects of atom-atom interactions on a clock transition frequency. These interactions are mediated by the dipole fields associated with the optically excited atoms. We predict resonancelike features in the frequency shifts when constructive interference among atomic dipoles occur. We theoretically demonstrate that by fine tuning the coherent dipole-dipole couplings in appropriately designed lattice geometries, the undesirable frequency shifts can be greatly suppressed.

  14. The Atomic Energy Commission By Alice Buck

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

    Atomic Energy Commission By Alice Buck July 1983 U.S. Department of Energy Office of Management Office of the Executive Secretariat Office of History and Heritage Resources 1 Introduction Almost a year after World War II ended, Congress established the United States Atomic Energy Commission to foster and control the peacetime development of atomic science and technology. Reflecting America's postwar optimism, Congress declared that atomic energy should be employed not only in the Nation's

  15. How Atomic Vibrations Transform Vanadium Dioxide

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

    How Atomic Vibrations Transform Vanadium Dioxide How Atomic Vibrations Transform Vanadium Dioxide Calculations Confirm Material's Potential for Next-Generation Electronics, Energy November 10, 2014 Contact: Dawn Levy, levyd@ornl.gov, 865.576.6448 Budaivibe Vanadium atoms (blue) have unusually large thermal vibrations that stabilize the metallic state of a vanadium dioxide crystal. Red depicts oxygen atoms. Image credit: Oak Ridge National Laboratory For more than 50 years, scientists have

  16. Gauss Sum Factorization with Cold Atoms

    SciTech Connect (OSTI)

    Gilowski, M.; Wendrich, T.; Mueller, T.; Ertmer, W.; Rasel, E. M. [Institut fuer Quantenoptik, Leibniz Universitaet Hannover, Welfengarten 1, D-30167 Hannover (Germany); Jentsch, Ch. [Astrium GmbH-Satellites, 88039 Friedrichshafen (Germany); Schleich, W. P. [Institut fuer Quantenphysik, Universitaet Ulm, Albert-Einstein-Allee 11, D-89081 Ulm (Germany)

    2008-01-25

    We report the first implementation of a Gauss sum factorization algorithm by an internal state Ramsey interferometer using cold atoms. A sequence of appropriately designed light pulses interacts with an ensemble of cold rubidium atoms. The final population in the involved atomic levels determines a Gauss sum. With this technique we factor the number N=263193.

  17. Can binuclear atoms solve the cold fusion puzzle

    SciTech Connect (OSTI)

    Cerofolini, G.F. ); Para, A.F. )

    1993-01-01

    The internal and external inconsistencies of cold fusion phenomena are discussed. It is shown that most of these inconsistencies can be removed by assuming the formation of binuclear atoms that have the ability to trap thermal neutrons from the natural background in a localized state. 29 refs., 3 figs.

  18. Laser-cooled atomic ions as probes of molecular ions

    SciTech Connect (OSTI)

    Brown, Kenneth R.; Viteri, C. Ricardo; Clark, Craig R.; Goeders, James E.; Khanyile, Ncamiso B.; Vittorini, Grahame D.

    2015-01-22

    Trapped laser-cooled atomic ions are a new tool for understanding cold molecular ions. The atomic ions not only sympathetically cool the molecular ions to millikelvin temperatures, but the bright atomic ion fluorescence can also serve as a detector of both molecular reactions and molecular spectra. We are working towards the detection of single molecular ion spectra by sympathetic heating spectroscopy. Sympathetic heating spectroscopy uses the coupled motion of two trapped ions to measure the spectra of one ion by observing changes in the fluorescence of the other ion. Sympathetic heating spectroscopy is a generalization of quantum logic spectroscopy, but does not require ions in the motional ground state or coherent control of the ion internal states. We have recently demonstrated this technique using two isotopes of Ca{sup +} [Phys. Rev. A, 81, 043428 (2010)]. Limits of the method and potential applications for molecular spectroscopy are discussed.

  19. Atomic Structure Calculations from the Los Alamos Atomic Physics Codes

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Cowan, R. D.

    The well known Hartree-Fock method of R.D. Cowan, developed at Los Alamos National Laboratory, is used for the atomic structure calculations. Electron impact excitation cross sections are calculated using either the distorted wave approximation (DWA) or the first order many body theory (FOMBT). Electron impact ionization cross sections can be calculated using the scaled hydrogenic method developed by Sampson and co-workers, the binary encounter method or the distorted wave method. Photoionization cross sections and, where appropriate, autoionizations are also calculated. Original manuals for the atomic structure code, the collisional excitation code, and the ionization code, are available from this website. Using the specialized interface, you will be able to define the ionization stage of an element and pick the initial and final configurations. You will be led through a series of web pages ending with a display of results in the form of cross sections, collision strengths or rates coefficients. Results are available in tabular and graphic form.

  20. QUANTUM MECHANICS, GENERAL PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS...

    Office of Scientific and Technical Information (OSTI)

    of model atoms in fields Milonni, P.W. 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS; ATOMS; OPTICAL MODELS; QUANTUM MECHANICS;...

  1. Mexico: swapping crude for atoms

    SciTech Connect (OSTI)

    Navarro, B.

    1982-06-24

    Mexico, considered the Saudi Arabia of the Western Hemisphere because of its proven and potential petroleum reserves, has surprised the world: it has embarked on the biggest nuclear-electric program in the Third World, only to postpone it days before scheduled approval of an international bidding (on which the atomic energy industry had pinned its hopes). A graph shows Mexican supplies of electricity by source with official projections to 1990. The point of entrance of the first nuclear reactor, originally scheduled for 1982, won't come onstream until 1983; and how nuclear-generated electricity grows close to 5% of the total in 1990. The big question is, will the future President of Mexico give the green light to the atomic megaproject. And if he does, how will Mexico deal with the serious logistics problems and grave ecological implications confronting the industry worldwide. In this issue, the author and Energy Detente touch on these questions and review the nuclear power status of Mexico, as well as addressing some of its global problems. Also presented in this issue is an update of the fuel price/tax series for the Western Hemisphere countries.

  2. Sensing mode atomic force microscope

    DOE Patents [OSTI]

    Hough, Paul V. C.; Wang, Chengpu

    2006-08-22

    An atomic force microscope is described having a cantilever comprising a base and a probe tip on an end opposite the base; a cantilever drive device connected to the base; a magnetic material coupled to the probe tip, such that when an incrementally increasing magnetic field is applied to the magnetic material an incrementally increasing force will be applied to the probe tip; a moveable specimen base; and a controller constructed to obtain a profile height of a specimen at a point based upon a contact between the probe tip and a specimen, and measure an adhesion force between the probe tip and the specimen by, under control of a program, incrementally increasing an amount of a magnetic field until a release force, sufficient to break the contact, is applied. An imaging method for atomic force microscopy involving measuring a specimen profile height and adhesion force at multiple points within an area and concurrently displaying the profile and adhesion force for each of the points is also described. A microscope controller is also described and is constructed to, for a group of points, calculate a specimen height at a point based upon a cantilever deflection, a cantilever base position and a specimen piezo position; calculate an adhesion force between a probe tip and a specimen at the point by causing an incrementally increasing force to be applied to the probe tip until the probe tip separates from a specimen; and move the probe tip to a new point in the group.

  3. Sensing mode atomic force microscope

    DOE Patents [OSTI]

    Hough, Paul V. C.; Wang, Chengpu

    2003-01-01

    An atomic force microscope utilizes a pulse release system and improved method of operation to minimize contact forces between a probe tip affixed to a flexible cantilever and a specimen being measured. The pulse release system includes a magnetic particle affixed proximate the probe tip and an electromagnetic coil. When energized, the electromagnetic coil generates a magnetic field which applies a driving force on the magnetic particle sufficient to overcome adhesive forces exhibited between the probe tip and specimen. The atomic force microscope includes two independently displaceable piezo elements operable along a Z-axis. A controller drives the first Z-axis piezo element to provide a controlled approach between the probe tip and specimen up to a point of contact between the probe tip and specimen. The controller then drives the first Z-axis piezo element to withdraw the cantilever from the specimen. The controller also activates the pulse release system which drives the probe tip away from the specimen during withdrawal. Following withdrawal, the controller adjusts the height of the second Z-axis piezo element to maintain a substantially constant approach distance between successive samples.

  4. Sensing mode atomic force microscope

    DOE Patents [OSTI]

    Hough, Paul V.; Wang, Chengpu

    2004-11-16

    An atomic force microscope is described having a cantilever comprising a base and a probe tip on an end opposite the base; a cantilever drive device connected to the base; a magnetic material coupled to the probe tip, such that when an incrementally increasing magnetic field is applied to the magnetic material an incrementally increasing force will be applied to the probe tip; a moveable specimen base; and a controller constructed to obtain a profile height of a specimen at a point based upon a contact between the probe tip and a specimen, and measure an adhesion force between the probe tip and the specimen by, under control of a program, incrementally increasing an amount of a magnetic field until a release force, sufficient to break the contact, is applied. An imaging method for atomic force microscopy involving measuring a specimen profile height and adhesion force at multiple points within an area and concurrently displaying the profile and adhesion force for each of the points is also described. A microscope controller is also described and is constructed to, for a group of points, calculate a specimen height at a point based upon a cantilever deflection, a cantilever base position and a specimen piezo position; calculate an adhesion force between a probe tip and a specimen at the point by causing an incrementally increasing force to be applied to the probe tip until the probe tip separates from a specimen; and move the probe tip to a new point in the group.

  5. Truman Signs Atomic Energy Act | National Nuclear Security Administration |

    National Nuclear Security Administration (NNSA)

    (NNSA) Truman Signs Atomic Energy Act Truman Signs Atomic Energy Act Washington, DC President Truman signs the Atomic Energy Act of 1946, leading to the creation of the Atomic Energy Commission

  6. Hyperbaric Hydrothermal Atomic Force Microscope

    DOE Patents [OSTI]

    Knauss, Kevin G.; Boro, Carl O.; Higgins, Steven R.; Eggleston, Carrick M.

    2003-07-01

    A hyperbaric hydrothermal atomic force microscope (AFM) is provided to image solid surfaces in fluids, either liquid or gas, at pressures greater than normal atmospheric pressure. The sample can be heated and its surface imaged in aqueous solution at temperatures greater than 100.degree. C. with less than 1 nm vertical resolution. A gas pressurized microscope base chamber houses the stepper motor and piezoelectric scanner. A chemically inert, flexible membrane separates this base chamber from the sample cell environment and constrains a high temperature, pressurized liquid or gas in the sample cell while allowing movement of the scanner. The sample cell is designed for continuous flow of liquid or gas through the sample environment.

  7. Hyperbaric hydrothermal atomic force microscope

    DOE Patents [OSTI]

    Knauss, Kevin G.; Boro, Carl O.; Higgins, Steven R.; Eggleston, Carrick M.

    2002-01-01

    A hyperbaric hydrothermal atomic force microscope (AFM) is provided to image solid surfaces in fluids, either liquid or gas, at pressures greater than normal atmospheric pressure. The sample can be heated and its surface imaged in aqueous solution at temperatures greater than 100.degree. C. with less than 1 nm vertical resolution. A gas pressurized microscope base chamber houses the stepper motor and piezoelectric scanner. A chemically inert, flexible membrane separates this base chamber from the sample cell environment and constrains a high temperature, pressurized liquid or gas in the sample cell while allowing movement of the scanner. The sample cell is designed for continuous flow of liquid or gas through the sample environment.

  8. The Manhattan Project: Making the Atomic Bomb | Department of Energy

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

    The Manhattan Project: Making the Atomic Bomb The Manhattan Project: Making the Atomic Bomb This report is an account of work on the atomic bomb. The Manhattan Project: Making the Atomic Bomb (6.17 MB) More Documents & Publications Gosling, The Manhattan Project: Making the Atomic Bomb The_Manhattan_Project_2010.pdf The Manhattan Project: Making of the Atomic Bomb

  9. Method for enhanced atomization of liquids

    DOE Patents [OSTI]

    Thompson, Richard E.; White, Jerome R.

    1993-01-01

    In a process for atomizing a slurry or liquid process stream in which a slurry or liquid is passed through a nozzle to provide a primary atomized process stream, an improvement which comprises subjecting the liquid or slurry process stream to microwave energy as the liquid or slurry process stream exits the nozzle, wherein sufficient microwave heating is provided to flash vaporize the primary atomized process stream.

  10. Atomicity violation detection using access interleaving invariants

    DOE Patents [OSTI]

    Zhou, Yuanyuan; Lu, Shan; Tucek, Joseph Andrew

    2013-09-10

    During execution of a program, the situation where the atomicity of a pair of instructions that are to be executed atomically is violated is identified, and a bug is detected as occurring in the program at the pair of instructions. The pairs of instructions that are to be executed atomically can be identified in different manners, such as by executing a program multiple times and using the results of those executions to automatically identify the pairs of instructions.

  11. Integrated Nanosystems for Atomically Precise Manufacturing Workshop -

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

    August 5-6, 2015 | Department of Energy Nanosystems for Atomically Precise Manufacturing Workshop - August 5-6, 2015 Integrated Nanosystems for Atomically Precise Manufacturing Workshop - August 5-6, 2015 The US Department of Energy (DOE) Advanced Manufacturing Office (AMO) hosted a Workshop on Integrated Nanosystems for Atomically Precise Manufacturing (INFAPM) in Berkeley, California, August 5-6, 2015. DOE invited representatives from academia, national labs, the Executive Office of the

  12. Collisionally induced atomic clock shifts and correlations

    SciTech Connect (OSTI)

    Band, Y. B.; Osherov, I.

    2011-07-15

    We develop a formalism to incorporate exchange symmetry considerations into the calculation of collisional frequency shifts for atomic clocks using a density-matrix formalism. The formalism is developed for both fermionic and bosonic atomic clocks. Numerical results for a finite-temperature {sup 87}Sr {sup 1}S{sub 0} (F=9/2) atomic clock in a magic wavelength optical lattice are presented.

  13. Clock Shifts of Optical Transitions in Ultracold Atomic Gases

    SciTech Connect (OSTI)

    Yu Zhenhua; Pethick, C. J.

    2010-01-08

    We calculate the shift, due to interatomic interactions, of an optical transition in an atomic Fermi gas trapped in an optical lattice, as in recent experiments of Campbell et al.[Science 324, 360 (2009)]. Using a pseudospin formalism to describe the density matrix of atoms, we derive a Bloch equation which incorporates both spatial inhomogeneity of the probe laser field and interatomic interactions. Expressions are given for the frequency shift as a function of pulse duration, detuning of the probe laser, and the spatial dependence of the electric field of the probe beam. In the low temperature semiclassical regime, we find that the magnitude of the shift is proportional to the temperature.

  14. Calculating Atomic Number Densities for Uranium

    Energy Science and Technology Software Center (OSTI)

    1993-01-01

    Provides method to calculate atomic number densities of selected uranium compounds and hydrogenous moderators for use in nuclear criticality safety analyses at gaseous diffusion uranium enrichment facilities.

  15. Atomic Scale Characterization of Compound Semiconductors using...

    Office of Scientific and Technical Information (OSTI)

    more fundamental understanding of carrier dynamics in photovoltaic (PV) device structures. ... Applying these improved analysis conditions to III-V based PV gives an atomic scale ...

  16. Manhattan Project: Adventures Inside the Atom

    Office of Scientific and Technical Information (OSTI)

    This publication was produced at the request of the the Assistant Manager for Public Education, Oak Ridge Operations Office, Atomic Energy Commission. It is reproduced here via the ...

  17. Circuits of Atoms on Wires of Light

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

    Circuits of Atoms on Wires of Light 1663 Los Alamos science and technology magazine Latest Issue:July 2016 past issues All Issues » submit Circuits of Atoms on Wires of Light A new kind of circuitry-with electrons on conducting wires replaced by atoms on paths of laser light-is ushering in an era of "atomtronic" technology. March 8, 2016 Artist visualization of atomic circuits Los Alamos scientists have developed a reliable new way to create atomtronic circuits with waves of

  18. Atomic Scale Characterization of Compound Semiconductors using...

    Office of Scientific and Technical Information (OSTI)

    Country of Publication: United States Language: English Subject: 14 SOLAR ENERGY; 36 MATERIALS SCIENCE; ALLOYS; ATOMS; DATA ACQUISITION; DIFFUSION; FUNCTIONALS; HEAT FLUX; ...

  19. Optimizing Atomic Neighborhoods for Speedier Chemical Reactions...

    Office of Science (SC) Website

    processes involved in energy production and pollution control. Employing in-operation tools to atomic-level interactions in palladium-based catalysts enhances the discovery and...

  20. Atom-split it for nuclear energy

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

    adjustments were provided by the 'Calutron Girls' Seaborg-Chairman of the Atomic Energy Commission 1961-1971; discovered many elements Buckyball-Buckminsterfullerene; 60...

  1. CERTIFICATION DOCKET WESTINGHOUSE ATOMIC POWER DEVELOPMENT PLANT

    Office of Legacy Management (LM)

    ... A survey cf the area of the "L' Building was performed and consisted of gamma-ray ... - Statement of Certification Westinghouse Atomic Power Development Plant East Pittsburgh ...

  2. Conduction of molecular electronic devices: Qualitative insights through atom-atom polarizabilities

    SciTech Connect (OSTI)

    Stuyver, T.; Fias, S. De Proft, F.; Geerlings, P.; Fowler, P. W.

    2015-03-07

    The atom-atom polarizability and the transmission probability at the Fermi level, as obtained through the source-and-sink-potential method for every possible configuration of contacts simultaneously, are compared for polycyclic aromatic compounds. This comparison leads to the conjecture that a positive atom-atom polarizability is a necessary condition for transmission to take place in alternant hydrocarbons without non-bonding orbitals and that the relative transmission probability for different configurations of the contacts can be predicted by analyzing the corresponding atom-atom polarizability. A theoretical link between the two considered properties is derived, leading to a mathematical explanation for the observed trends for transmission based on the atom-atom polarizability.

  3. Sub-Angstrom Atomic-Resolution Imaging of Heavy Atoms to Light...

    Office of Scientific and Technical Information (OSTI)

    of Heavy Atoms to Light Atoms Citation Details In-Document Search ... Publication Date: 2003-05-23 OSTI Identifier: 822959 Report Number(s): LBNL--52090 Journal ID: ISSN ...

  4. Atomic magnetometer for human magnetoencephalograpy.

    SciTech Connect (OSTI)

    Schwindt, Peter; Johnson, Cort N.

    2010-12-01

    We have developed a high sensitivity (<5 fTesla/{radical}Hz), fiber-optically coupled magnetometer to detect magnetic fields produced by the human brain. This is the first demonstration of a noncryogenic sensor that could replace cryogenic superconducting quantum interference device (SQUID) magnetometers in magnetoencephalography (MEG) and is an important advance in realizing cost-effective MEG. Within the sensor, a rubidium vapor is optically pumped with 795 laser light while field-induced optical rotations are measured with 780 nm laser light. Both beams share a single optical axis to maximize simplicity and compactness. In collaboration with neuroscientists at The Mind Research Network in Albuquerque, NM, the evoked responses resulting from median nerve and auditory stimulation were recorded with the atomic magnetometer and a commercial SQUID-based MEG system with signals comparing favorably. Multi-sensor operation has been demonstrated with two AMs placed on opposite sides of the head. Straightforward miniaturization would enable high-density sensor arrays for whole-head magnetoencephalography.

  5. Atomic Layer Deposition | Argonne National Laboratory

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

    Atomic Layer Deposition New nanophase thin film materials with properties tailored to specifically meet the needs of industry New software simulates ALD over multiple length scale, saving industry time and money on developing specialized tools PDF icon Atomic_Layer_Deposition

  6. Some topological states in one-dimensional cold atomic systems

    SciTech Connect (OSTI)

    Mei, Feng; Zhang, Dan-Wei; Zhu, Shi-Liang

    2015-07-15

    Ultracold atoms trapped in optical lattices nowadays have been widely used to mimic various models from condensed-matter physics. Recently, many great experimental progresses have been achieved for producing artificial magnetic field and spin–orbit coupling in cold atomic systems, which turn these systems into a new platform for simulating topological states. In this paper, we give a review focusing on quantum simulation of topologically protected soliton modes and topological insulators in one-dimensional cold atomic system. Firstly, the recent achievements towards quantum simulation of one-dimensional models with topological non-trivial states are reviewed, including the celebrated Jackiw–Rebbi model and Su–Schrieffer–Heeger model. Then, we will introduce a dimensional reduction method for systematically constructing high dimensional topological states in lower dimensional models and review its applications on simulating two-dimensional topological insulators in one-dimensional optical superlattices.

  7. A continuous cold atomic beam interferometer

    SciTech Connect (OSTI)

    Xue, Hongbo; Feng, Yanying Yan, Xueshu; Jiang, Zhikun; Chen, Shu; Wang, Xiaojia; Zhou, Zhaoying

    2015-03-07

    We demonstrate an atom interferometer that uses a laser-cooled continuous beam of {sup 87}Rb atoms having velocities of 10–20 m/s. With spatially separated Raman beams to coherently manipulate the atomic wave packets, Mach–Zehnder interference fringes are observed at an interference distance of 2L = 19 mm. The apparatus operates within a small enclosed area of 0.07 mm{sup 2} at a bandwidth of 190 Hz with a deduced sensitivity of 7.8×10{sup −5} rad/s/√(Hz) for rotations. Using a low-velocity continuous atomic source in an atom interferometer enables high sampling rates and bandwidths without sacrificing sensitivity and compactness, which are important for applications in real dynamic environments.

  8. The Manhattan Project: Making the atomic bomb

    SciTech Connect (OSTI)

    Gosling, F.G.

    1994-09-01

    This article is a short history of the origins and development of the American atomic bomb program during World War II. Beginning with the scientific developments of the pre-war years, the monograph details the role of US government in conducting a secret, nationwide enterprise that took science from the laboratory and into combat with an entirely new type of weapon. The monograph concludes with a discussion of the immediate postwar period, the debate over the Atomic Energy Act of 1946, and the founding of the Atomic Energy Commission.

  9. 1982 bibliography of atomic and molecular processes

    SciTech Connect (OSTI)

    Barnett, C.F.; Crandall, D.H.; Gilbody, H.B.; Gregory, D.C.; Kirkpatrick, M.I.; McDaniel, E.W.; McKnight, R.H.; Meyer, F.W.; Morgan, T.J.; Phaneuf, R.A.

    1984-05-01

    This annotated bibliography includes papers on atomic and molecular processes published during 1982. Sources include scientific journals, conference proceedings, and books. Each entry is designated by one or more of the 114 categories of atomic and molecular processes used by the Controlled Fusion Atomic Data Center, Oak Ridge National Laboratory to classify data. Also indicated is whether the work was experimental or theoretical, what energy range was covered, what reactants were investigated, and the country of origin of the first author. Following the bibliographical listing, the entries are indexed according to the categories and according to reactants within each subcategory.

  10. SECTION IV: ATOMIC AND MOLECULAR SCIENCE

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

    IV: ATOMIC AND MOLECULAR SCIENCE A Pyroelectric Crystal Particle Accelerator ....................................................................................................................................................IV-1 J. Kalodimos and R.L. Watson Polarization of Ka Satellite Transitions in Potassium .....................................................................................................................................IV-4 K. S. Fruchey, R.L. Watson, V. Horvat, and Yong

  11. Network Optimization Models (RNAS and ATOM) | NISAC

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

    been used to study policy options concerning the movement of toxic chemicals by rail. Air Transport Optimization Model (ATOM) The TOM is a network-optimization model designed to...

  12. SECTION IV: ATOMIC, MOLECULAR AND MATERIALS SCIENCE

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

    ATOMIC, MOLECULAR AND MATERIALS SCIENCE A semiempirical scaling law for target K x-ray production in heavy ion collisions...... IV-1 R. L. Watson, Y. Peng, V. Horvat, and A. ...

  13. Experimental observation of magic-wavelength behavior of {sup 87}Rb atoms in an optical lattice

    SciTech Connect (OSTI)

    Lundblad, N.; Schlosser, M.; Porto, J. V.

    2010-03-15

    We demonstrate the cancellation of the differential ac Stark shift of the microwave hyperfine clock transition in trapped {sup 87}Rb atoms. Recent progress in metrology exploits so-called magic wavelengths, whereby an atomic ensemble can be trapped with laser light whose wavelength is chosen so that both levels of an optical atomic transition experience identical ac Stark shifts. Similar magic-wavelength techniques are not possible for the microwave hyperfine transitions in the alkali metals due to their simple electronic structure. We show, however, that ac Stark shift cancellation is indeed achievable for certain values of wavelength, polarization, and magnetic field. The cancellation comes at the expense of a small magnetic-field sensitivity. The technique demonstrated here has implications for experiments involving the precise control of optically trapped neutral atoms.

  14. New analogies between extreme QCD and cold atoms

    SciTech Connect (OSTI)

    Nishida, Yusuke

    2012-08-15

    We discuss two new analogies between extreme QCD and cold atoms. One is the analogue of 'hard probes' in cold atoms. The other is the analogue of 'quark-hadron continuity' in cold atoms.

  15. August 1, 1946: Atomic Energy Act | Department of Energy

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

    August 1, 1946: Atomic Energy Act August 1, 1946 President Truman signs the Atomic Energy Act of 1946. On January 1, 1947, all atomic energy activities are transferred to the newly ...

  16. Atomic resolution images of graphite in air

    SciTech Connect (OSTI)

    Grigg, D.A.; Shedd, G.M.; Griffis, D.; Russell, P.E.

    1988-12-01

    One sample used for proof of operation for atomic resolution in STM is highly oriented pyrolytic graphite (HOPG). This sample has been imaged with many different STM`s obtaining similar results. Atomic resolution images of HOPG have now been obtained using an STM designed and built at the Precision Engineering Center. This paper discusses the theoretical predictions and experimental results obtained in imaging of HOPG.

  17. CERTIFICATION DOCKET WESTINGHOUSE ATOMIC POWER DEVELOPMENT PLANT

    Office of Legacy Management (LM)

    WESTINGHOUSE ATOMIC POWER DEVELOPMENT PLANT EAST PITTSBURGH PLANT FOREST HILLS PITTSBURGH, PENNSYLVANIA Department of Energy Office of Nuclear Energy Office of Terminal Waste Disposal and Remedial Action Division of Remedial Action Projects ..-.. --__- _".-.-l--_--l -_._ _- --- ~~~. . ..~ CONTENTS Page - - I NTRODUCTI ON 1 Purpose 1 Docket Contents 1 Exhibit I: Summary of Activities at Westinghouse Atomic Power Development Plant, East Pittsburgh Plant, Forest Hills, Pittsburgh, Pennsylvania

  18. The Common Elements of Atomic and Hadronic Physics (Conference...

    Office of Scientific and Technical Information (OSTI)

    The Common Elements of Atomic and Hadronic Physics Citation Details In-Document Search Title: The Common Elements of Atomic and Hadronic Physics Authors: Brodsky, Stanley J. ;...

  19. Order, disorder and mixing: The atomic structure of amorphous...

    Office of Scientific and Technical Information (OSTI)

    Order, disorder and mixing: The atomic structure of amorphous mixtures of titania and tantala Citation Details In-Document Search Title: Order, disorder and mixing: The atomic ...

  20. The perfect atom sandwich requires an extra layer > Archived...

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

    Titanium atoms (yellow) preferentially bond with oxygen atoms (gray) and sit at the center of a complete octahedron, making it energetically more favorable for titanium to switch ...

  1. Institute for Atom-Efficient Chemical Transformations Energy...

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

    Institute for Atom-Efficient Chemical Transformations - an Energy Frontier Research Center The Institute for Atom-Efficient Chemical Transformations (IACT) employs a...

  2. Institute for Atom-Efficient Chemical Transformations Energy...

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

    scientific roadblocks to U.S. energy security. Institute for Atom-Efficient Chemical Transformations The Institute for Atom-Efficient Chemical Transformations (IACT)...

  3. Atomic line emission analyzer for hydrogen isotopes (Patent)...

    Office of Scientific and Technical Information (OSTI)

    Atomic line emission analyzer for hydrogen isotopes Title: Atomic line emission analyzer for hydrogen isotopes Apparatus for isotopic analysis of hydrogen comprises a low pressure ...

  4. Spatial atomic layer deposition on flexible substrates using...

    Office of Scientific and Technical Information (OSTI)

    Spatial atomic layer deposition on flexible substrates using a modular rotating cylinder reactor Citation Details In-Document Search Title: Spatial atomic layer deposition on...

  5. Charge flow model for atomic ordering in nonisovalent alloys...

    Office of Scientific and Technical Information (OSTI)

    Charge flow model for atomic ordering in nonisovalent alloys Title: Charge flow model for atomic ordering in nonisovalent alloys Authors: Wang, Shuzhi ; Wang, Lin-Wang Publication ...

  6. Hewlett and Duncan - Atomic Shield | Department of Energy

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

    Duncan - Atomic Shield Hewlett and Duncan - Atomic Shield Hewlett, Richard G. and Francis Duncan. Atomic Shield, 1947-1952. U.S. Atomic Energy Comission, 1972. The second volume of the three volume A History of the United States Atomic Energy Commission. Text in each PDF is fully searchable. "Hewlett and Duncan - Atomic Shield (complete).pdf" contains the complete text and images from Atomic Shield. 12mb "Hewlett and Duncan - Atomic Shield (figures only).pdf" contains hi-res

  7. Los Alamos Selected as Atomic Weapons Laboratory | National Nuclear...

    National Nuclear Security Administration (NNSA)

    Los Alamos Selected as Atomic Weapons Laboratory Los Alamos, NM Groves selects Los Alamos, New Mexico, as site for separate scientific laboratory to design an atomic bomb

  8. Signals from dark atom formation in halos (Journal Article) ...

    Office of Scientific and Technical Information (OSTI)

    Signals from dark atom formation in halos Prev Next Title: Signals from dark atom formation in halos Authors: Pearce, Lauren ; Petraki, Kalliopi ; Kusenko, Alexander ...

  9. The Simplicity of Perfect Atoms: Degeneracies in Supersymmetric...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: The Simplicity of Perfect Atoms: Degeneracies in Supersymmetric Hydrogen Citation Details In-Document Search Title: The Simplicity of Perfect Atoms: Degeneracies...

  10. The Simplicity of Perfect Atoms: Degeneracies in Supersymmetric...

    Office of Scientific and Technical Information (OSTI)

    The Simplicity of Perfect Atoms: Degeneracies in Supersymmetric Hydrogen Citation Details In-Document Search Title: The Simplicity of Perfect Atoms: Degeneracies in Supersymmetric...

  11. Ultra-sensitive Magnetic Microscopy with an Atomic Magnetometer...

    Office of Scientific and Technical Information (OSTI)

    Country of Publication: United States Language: English Subject: 74 ATOMIC AND ... PERFORMANCE TESTING; SENSITIVITY; DATA ACQUISITION SYSTEMS; ALKALI METALS; ATOMS Word ...

  12. Clifford G. Shull, Neutron Diffraction, Hydrogen Atoms, and Neutron...

    Office of Scientific and Technical Information (OSTI)

    In Professor Shull's opinion the most important problem he worked on at the time dealt with determining the positions of hydrogen atoms in materials. "Hydrogen atoms are ubiquitous ...

  13. Atomic Layer Deposition of Metal Sulfide Materials | Argonne...

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

    Atomic Layer Deposition of Metal Sulfide Materials Title Atomic Layer Deposition of Metal Sulfide Materials Publication Type Journal Article Year of Publication 2015 Authors...

  14. Atom probe tomographic mapping directly reveals the atomic distribution of phosphorus in resin embedded ferritin

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

    Perea, Daniel E.; Liu, Jia; Bartrand, Jonah A. G.; Dicken, Quinten G.; Thevuthasan, Suntharampillai Theva; Browning, Nigel D.; Evans, James E.

    2016-02-29

    In this study, we report the atomic-scale analysis of biological interfaces using atom probe tomography. Embedding the protein ferritin in an organic polymer resin lacking nitrogen provided chemical contrast to visualize atomic distributions and distinguish organic-organic and organic-inorganic interfaces. The sample preparation method can be directly extended to further enhance the study of biological, organic and inorganic nanomaterials relevant to health, energy or the environment.

  15. Atoms for peace and war, 1953-1961: Eisenhower and the Atomic Energy Commission

    SciTech Connect (OSTI)

    Hewlett, Richard G.; Holl, Jack M.

    1989-12-01

    This third volume in the official history of the U.S. Atomic Energy Commission covers the years of the Eisenhower Administration.

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

    SciTech Connect (OSTI)

    Argonov, V. Yu.

    2014-11-15

    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.

  17. Temperature measurement of cold atoms using single-atom transits and Monte Carlo simulation in a strongly coupled atom-cavity system

    SciTech Connect (OSTI)

    Li, Wenfang; Du, Jinjin; Wen, Ruijuan; Yang, Pengfei; Li, Gang; Zhang, Tiancai; Liang, Junjun

    2014-03-17

    We investigate the transmission of single-atom transits based on a strongly coupled cavity quantum electrodynamics system. By superposing the transit transmissions of a considerable number of atoms, we obtain the absorption spectra of the cavity induced by single atoms and obtain the temperature of the cold atom. The number of atoms passing through the microcavity for each release is also counted, and this number changes exponentially along with the atom temperature. Monte Carlo simulations agree closely with the experimental results, and the initial temperature of the cold atom is determined. Compared with the conventional time-of-flight (TOF) method, this approach avoids some uncertainties in the standard TOF and sheds new light on determining temperature of cold atoms by counting atoms individually in a confined space.

  18. Method and apparatus for atomic imaging

    DOE Patents [OSTI]

    Saldin, Dilano K.; de Andres Rodriquez, Pedro L.

    1993-01-01

    A method and apparatus for three dimensional imaging of the atomic environment of disordered adsorbate atoms are disclosed. The method includes detecting and measuring the intensity of a diffuse low energy electron diffraction pattern formed by directing a beam of low energy electrons against the surface of a crystal. Data corresponding to reconstructed amplitudes of a wave form is generated by operating on the intensity data. The data corresponding to the reconstructed amplitudes is capable of being displayed as a three dimensional image of an adsorbate atom. The apparatus includes a source of a beam of low energy electrons and a detector for detecting the intensity distribution of a DLEED pattern formed at the detector when the beam of low energy electrons is directed onto the surface of a crystal. A device responsive to the intensity distribution generates a signal corresponding to the distribution which represents a reconstructed amplitude of a wave form and is capable of being converted into a three dimensional image of the atomic environment of an adsorbate atom on the crystal surface.

  19. Layered Atom Arrangements in Complex Materials

    SciTech Connect (OSTI)

    K.E. Sikafus; R.W.Grimes; S.M.Corish; A.R. Cleave; M.Tang; C.R.Stanek; B.P. Uberuaga; J.A.Valdez

    2005-04-15

    In this report, we develop an atom layer stacking model to describe systematically the crystal structures of complex materials. To illustrate the concepts, we consider a sequence of oxide compounds in which the metal cations progress in oxidation state from monovalent (M{sup 1+}) to tetravalent (M{sup 4+}). We use concepts relating to geometric subdivisions of a triangular atom net to describe the layered atom patterns in these compounds (concepts originally proposed by Shuichi Iida). We demonstrate that as a function of increasing oxidation state (from M{sup 1+} to M{sup 4+}), the layer stacking motifs used to generate each successive structure (specifically, motifs along a 3 symmetry axis), progress through the following sequence: MMO, MO, M{sub r}O, MO{sub r/s}O{sub u/v}, MOO (where M and O represent fully dense triangular atom nets and r/s and u/v are fractions used to describe partially filled triangular atom nets). We also develop complete crystallographic descriptions for the compounds in our oxidation sequence using trigonal space group R{bar 3}.

  20. Permutation-invariant distance between atomic configurations

    SciTech Connect (OSTI)

    Ferré, Grégoire; Maillet, Jean-Bernard; Stoltz, Gabriel

    2015-09-14

    We present a permutation-invariant distance between atomic configurations, defined through a functional representation of atomic positions. This distance enables us to directly compare different atomic environments with an arbitrary number of particles, without going through a space of reduced dimensionality (i.e., fingerprints) as an intermediate step. Moreover, this distance is naturally invariant through permutations of atoms, avoiding the time consuming associated minimization required by other common criteria (like the root mean square distance). Finally, the invariance through global rotations is accounted for by a minimization procedure in the space of rotations solved by Monte Carlo simulated annealing. A formal framework is also introduced, showing that the distance we propose verifies the property of a metric on the space of atomic configurations. Two examples of applications are proposed. The first one consists in evaluating faithfulness of some fingerprints (or descriptors), i.e., their capacity to represent the structural information of a configuration. The second application concerns structural analysis, where our distance proves to be efficient in discriminating different local structures and even classifying their degree of similarity.

  1. Efimov physics in {sup 6}Li atoms

    SciTech Connect (OSTI)

    Braaten, Eric; Hammer, H.-W.; Kang, Daekyoung; Platter, Lucas

    2010-01-15

    A new narrow three-atom loss resonance associated with an Efimov trimer crossing the three-atom threshold has recently been discovered in a many-body system of ultracold {sup 6}Li atoms in the three lowest hyperfine spin states at a magnetic field near 895 G. O'Hara and coworkers have used measurements of the three-body recombination rate in this region to determine the complex three-body parameter associated with Efimov physics. Using this parameter as the input, we calculate the universal predictions for the spectrum of Efimov states and for the three-body recombination rate in the universal region above 600 G where all three scattering lengths are large. We predict an atom-dimer loss resonance at 672+-2 G associated with an Efimov trimer disappearing through an atom-dimer threshold. We also predict an interference minimum in the three-body recombination rate at 759+-1 G where the three-spin mixture may be sufficiently stable to allow experimental study of the many-body system.

  2. Atomic-Level Sculpting of Crystalline Oxides: Toward Bulk Nanofabrication with Single Atomic Plane Precision

    SciTech Connect (OSTI)

    Jesse, Stephen; He, Qian; Lupini, Andrew R.; Leonard, Donovan N.; Oxley, Mark P.; Ovchinnikov, Oleg; Unocic, Raymond R.; Tselev, Alexander; Fuentes-Cabrera, Miguel; Sumpter, Bobby G.; Pennycook, Stephen J.; Kalinin, Sergei V.; Borisevich, Albina Y.

    2015-10-19

    We demonstrate atomic-level sculpting of 3D crystalline oxide nanostructures from metastable amorphous layer in a scanning transmission electron microscope (STEM). Strontium titanate nanostructures grow epitaxially from the crystalline substrate following the beam path. This method can be used for fabricating crystalline structures as small as 1-2 nm and the process can be observed in situ with atomic resolution. We further demonstrate fabrication of arbitrary shape structures via control of the position and scan speed of the electron beam. Combined with broad availability of the atomic resolved electron microscopy platforms, these observations suggest the feasibility of large scale implementation of bulk atomic-level fabrication as a new enabling tool of nanoscience and technology, providing a bottom-up, atomic-level complement to 3D printing.

  3. Atomic-Level Sculpting of Crystalline Oxides: Toward Bulk Nanofabrication with Single Atomic Plane Precision

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

    Jesse, Stephen; He, Qian; Lupini, Andrew R.; Leonard, Donovan N.; Oxley, Mark P.; Ovchinnikov, Oleg; Unocic, Raymond R.; Tselev, Alexander; Fuentes-Cabrera, Miguel; Sumpter, Bobby G.; et al

    2015-10-19

    We demonstrate atomic-level sculpting of 3D crystalline oxide nanostructures from metastable amorphous layer in a scanning transmission electron microscope (STEM). Strontium titanate nanostructures grow epitaxially from the crystalline substrate following the beam path. This method can be used for fabricating crystalline structures as small as 1-2 nm and the process can be observed in situ with atomic resolution. We further demonstrate fabrication of arbitrary shape structures via control of the position and scan speed of the electron beam. Combined with broad availability of the atomic resolved electron microscopy platforms, these observations suggest the feasibility of large scale implementation of bulkmore » atomic-level fabrication as a new enabling tool of nanoscience and technology, providing a bottom-up, atomic-level complement to 3D printing.« less

  4. A History of the Atomic Energy Commission | Department of Energy

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

    Atomic Energy Commission A History of the Atomic Energy Commission A History of the Atomic Energy Commission - written by Alice L. Buck Washington, D.C.: U.S. Department of Energy, July 1983. 41 pp. AEC History.pdf (1.01 MB) More Documents & Publications The History of Nuclear Energy The Manhattan Project Hewlett and Holl - Atoms for Peace and War

  5. Light-pulse atom interferometric device

    DOE Patents [OSTI]

    Biedermann, Grant; McGuinness, Hayden James Evans; Rakholia, Akash; Jau, Yuan-Yu; Schwindt, Peter; Wheeler, David R.

    2016-03-22

    An atomic interferometric device useful, e.g., for measuring acceleration or rotation is provided. The device comprises at least one vapor cell containing a Raman-active chemical species, an optical system, and at least one detector. The optical system is conformed to implement a Raman pulse interferometer in which Raman transitions are stimulated in a warm vapor of the Raman-active chemical species. The detector is conformed to detect changes in the populations of different internal states of atoms that have been irradiated by the optical system.

  6. SECTION IV. ATOMIC AND MOLECULAR SCIENCE

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

    IV. ATOMIC AND MOLECULAR SCIENCE Cross Sections for Cu K-Vacancy Production in Fast Heavy Ion Collisions R.L. Watson, J.M. Blackadar and V. Horvat Enhancement of the Cu Kα x-ray Diagram Lines in Fast Heavy Ion Collisions R.L. Watson, V. Horvat and J.M. Blackadar K-shell Ionization by Secondary Electrons V. Horvat, R.L. Watson and J.M. Blackadar Target-atom Inner-shell Vacancy Distributions Created in Collisions with Heavy Ion Projectiles V. Horvat, R.L. Watson and J.M. Blackadar Systematics of

  7. Atom Probe Tomography of Nanoscale Electronic Materials

    SciTech Connect (OSTI)

    Larson, David J.; Prosa, Ty J.; Perea, Daniel E.; Inoue, Hidekazu; Mangelinck, D.

    2016-01-01

    Atom probe tomography (APT) is a mass spectrometry based on time-of-flight measurements which also concurrently produces 3D spatial information. The reader is referred to any of the other papers in this volume or to the following references for further information 4–8. The current capabilities of APT, such as detecting a low number of dopant atoms in nanoscale devices or segregation at a nanoparticle interface, make this technique an important component in the nanoscale metrology toolbox. In this manuscript, we review some of the applications of APT to nanoscale electronic materials, including transistors and finFETs, silicide contact microstructures, nanowires, and nanoparticles.

  8. Committee on Atomic, Molecular and Optical Sciences

    SciTech Connect (OSTI)

    Lancaster, James

    2015-06-30

    The Committee on Atomic, Molecular, and Optical Sciences (CAMOS) is a standing activity of the National Research Council (NRC) that operates under the auspices of the Board on Physics and Astronomy. CAMOS is one of five standing committees of the BPA that are charged with assisting it in achieving its goals—monitoring the health of physics and astronomy, identifying important new developments at the scientific forefronts, fostering interactions with other fields, strengthening connections to technology, facilitating effective service to the nation, and enhancing education in physics. CAMOS provides these capabilities for the atomic, molecular and optical (AMO) sciences.

  9. NREL: Measurements and Characterization - Atomic Force Microscopy

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

    Atomic Force Microscopy Atomic Force Microscopy (AFM) operates in several modes. In contact mode, a tip that is attached to a cantilever is scanned over the sample surface, while the force between tip and sample is measured. While the tip is scanned laterally, the force is kept constant by moving the cantilever/tip assembly up and down, so that the deflection of the cantilever is kept constant. The vertical movement of the cantilever/tip assembly is recorded and used to generate an image of the

  10. Fidelity imaging for atomic force microscopy

    SciTech Connect (OSTI)

    Ghosal, Sayan Salapaka, Murti

    2015-01-05

    Atomic force microscopy is widely employed for imaging material at the nanoscale. However, real-time measures on image reliability are lacking in contemporary atomic force microscopy literature. In this article, we present a real-time technique that provides an image of fidelity for a high bandwidth dynamic mode imaging scheme. The fidelity images define channels that allow the user to have additional authority over the choice of decision threshold that facilitates where the emphasis is desired, on discovering most true features on the sample with the possible detection of high number of false features, or emphasizing minimizing instances of false detections. Simulation and experimental results demonstrate the effectiveness of fidelity imaging.

  11. Isolating and moving single atoms using silicon nanocrystals

    DOE Patents [OSTI]

    Carroll, Malcolm S.

    2010-09-07

    A method is disclosed for isolating single atoms of an atomic species of interest by locating the atoms within silicon nanocrystals. This can be done by implanting, on the average, a single atom of the atomic species of interest into each nanocrystal, and then measuring an electrical charge distribution on the nanocrystals with scanning capacitance microscopy (SCM) or electrostatic force microscopy (EFM) to identify and select those nanocrystals having exactly one atom of the atomic species of interest therein. The nanocrystals with the single atom of the atomic species of interest therein can be sorted and moved using an atomic force microscope (AFM) tip. The method is useful for forming nanoscale electronic and optical devices including quantum computers and single-photon light sources.

  12. Atomic-level imaging, processing and characterization of semiconductor surfaces

    DOE Patents [OSTI]

    Kazmerski, Lawrence L.

    1995-01-01

    A method for selecting and removing single specific atoms from a solid material surface uses photon biasing to break down bonds that hold the selected atom in the lattice and to reduce barrier effects that hold the atom from transferring to a probe. The photon bias is preferably light or other electromagnetic radiation with a wavelength and frequency that approximately matches the wave function of the target atom species to be removed to induce high energy, selective thermionic-like vibration. An electric field potential is then applied between the probe and the surface of the solid material to pull the atom out of the lattice and to transfer the atom to the probe. Different extrinsic atoms can be installed in the lattice sites that are vacated by the removed atoms by using a photon bias that resonates the extrinsic atom species, reversing polarity of the electric field, and blowing gas comprising the extrinsic atoms through a hollow catheter probe.

  13. Atomic-level imaging, processing and characterization of semiconductor surfaces

    DOE Patents [OSTI]

    Kazmerski, L.L.

    1995-08-22

    A method for selecting and removing single specific atoms from a solid material surface uses photon biasing to break down bonds that hold the selected atom in the lattice and to reduce barrier effects that hold the atom from transferring to a probe. The photon bias is preferably light or other electromagnetic radiation with a wavelength and frequency that approximately matches the wave function of the target atom species to be removed to induce high energy, selective thermionic-like vibration. An electric field potential is then applied between the probe and the surface of the solid material to pull the atom out of the lattice and to transfer the atom to the probe. Different extrinsic atoms can be installed in the lattice sites that are vacated by the removed atoms by using a photon bias that resonates the extrinsic atom species, reversing polarity of the electric field, and blowing gas comprising the extrinsic atoms through a hollow catheter probe. 8 figs.

  14. Dual-axis high-data-rate atom interferometer via cold ensemble exchange

    SciTech Connect (OSTI)

    Rakholia, Akash V.; McGuinness, Hayden J.; Biedermann, Grant W.

    2014-11-24

    We demonstrate a dual-axis accelerometer and gyroscope atom interferometer, which can form the building blocks of a six-axis inertial measurement unit. By recapturing the atoms after the interferometer sequence, we maintain a large atom number at high data rates of 50 to 100 measurements per second. Two cold ensembles are formed in trap zones located a few centimeters apart and are launched toward one another. During their ballistic trajectory, they are interrogated with a stimulated Raman sequence, detected, and recaptured in the opposing trap zone. As a result, we achieve sensitivities at ?g/ ?Hz and ?rad/s/ ?Hz levels, making this a compelling prospect for expanding the use of atom interferometer inertial sensors beyond benign laboratory environments.

  15. Dual-axis high-data-rate atom interferometer via cold ensemble exchange

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

    Rakholia, Akash V.; McGuinness, Hayden J.; Biedermann, Grant W.

    2014-11-24

    We demonstrate a dual-axis accelerometer and gyroscope atom interferometer, which can form the building blocks of a six-axis inertial measurement unit. By recapturing the atoms after the interferometer sequence, we maintain a large atom number at high data rates of 50 to 100 measurements per second. Two cold ensembles are formed in trap zones located a few centimeters apart and are launched toward one another. During their ballistic trajectory, they are interrogated with a stimulated Raman sequence, detected, and recaptured in the opposing trap zone. As a result, we achieve sensitivities at μg/ √Hz and μrad/s/ √Hz levels, making thismore » a compelling prospect for expanding the use of atom interferometer inertial sensors beyond benign laboratory environments.« less

  16. Mobility of atoms under ion bombardment

    SciTech Connect (OSTI)

    Alekseevskii, V.; Gertsriken, D.; Kovtun, V.; Tyshkevich, V.; Fal'chenko, V.

    1981-10-01

    Argon ions bombardment (Eapprox.1KeV) of Armco iron in a cold glow discharge plasma (T< or approx. =150/sup 0/C) has been performed to investigate the mobility and behavior of the atoms in the crystal lattice and the formation of a solid solution of Argon in iron.(AIP)

  17. Quantum measurements of atoms using cavity QED

    SciTech Connect (OSTI)

    Dada, Adetunmise C.; Andersson, Erika [SUPA, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom); Jones, Martin L.; Kendon, Vivien M. [School of Physics and Astronomy, University of Leeds, Woodhouse Lane, Leeds LS2 9JT (United Kingdom); Everitt, Mark S. [School of Physics and Astronomy, University of Leeds, Woodhouse Lane, Leeds LS2 9JT (United Kingdom); National Institute of Informatics, 2-1-2 Hitotsubashi, Chiyoda ku, Tokyo 101-8430 (Japan)

    2011-04-15

    Generalized quantum measurements are an important extension of projective or von Neumann measurements in that they can be used to describe any measurement that can be implemented on a quantum system. We describe how to realize two nonstandard quantum measurements using cavity QED. The first measurement optimally and unambiguously distinguishes between two nonorthogonal quantum states. The second example is a measurement that demonstrates superadditive quantum coding gain. The experimental tools used are single-atom unitary operations effected by Ramsey pulses and two-atom Tavis-Cummings interactions. We show how the superadditive quantum coding gain is affected by errors in the field-ionization detection of atoms and that even with rather high levels of experimental imperfections, a reasonable amount of superadditivity can still be seen. To date, these types of measurements have been realized only on photons. It would be of great interest to have realizations using other physical systems. This is for fundamental reasons but also since quantum coding gain in general increases with code word length, and a realization using atoms could be more easily scaled than existing realizations using photons.

  18. Nano-soldering to single atomic layer

    DOE Patents [OSTI]

    Girit, Caglar O.; Zettl, Alexander K.

    2011-10-11

    A simple technique to solder submicron sized, ohmic contacts to nanostructures has been disclosed. The technique has several advantages over standard electron beam lithography methods, which are complex, costly, and can contaminate samples. To demonstrate the soldering technique graphene, a single atomic layer of carbon, has been contacted, and low- and high-field electronic transport properties have been measured.

  19. Atomic power in space: A history

    SciTech Connect (OSTI)

    Not Available

    1987-03-01

    ''Atomic Power in Space,'' a history of the Space Isotope Power Program of the United States, covers the period from the program's inception in the mid-1950s through 1982. Written in non-technical language, the history is addressed to both the general public and those more specialized in nuclear and space technologies. 19 figs., 3 tabs.

  20. Atomic physics with highly charged ions

    SciTech Connect (OSTI)

    Richard, P.

    1991-08-01

    This report discusses: One electron outer shell processes in fast ion-atom collisions; role of electron-electron interaction in two-electron processes; multi-electron processes at low energy; multi-electron processes at high energy; inner shell processes; molecular fragmentation studies; theory; and, JRM laboratory operations.

  1. Theory of multiphoton ionization of atoms

    SciTech Connect (OSTI)

    Szoeke, A.

    1986-03-01

    A non-perturbative approach to the theory of multiphoton ionization is reviewed. Adiabatic Floquet theory is its first approximation. It explains qualitatively the energy and angular distribution of photoelectrons. In many-electron atoms it predicts collective and inner shell excitation. 14 refs.

  2. Molecular Beam Studies of Hot Atom Chemical Reactions: Reactive Scattering of Energetic Deuterium Atoms

    DOE R&D Accomplishments [OSTI]

    Continetti, R. E.; Balko, B. A.; Lee, Y. T.

    1989-02-01

    A brief review of the application of the crossed molecular beams technique to the study of hot atom chemical reactions in the last twenty years is given. Specific emphasis is placed on recent advances in the use of photolytically produced energetic deuterium atoms in the study of the fundamental elementary reactions D + H{sub 2} -> DH + H and the substitution reaction D + C{sub 2}H{sub 2} -> C{sub 2}HD + H. Recent advances in uv laser and pulsed molecular beam techniques have made the detailed study of hydrogen atom reactions under single collision conditions possible.

  3. The atomization of water-oil emulsions

    SciTech Connect (OSTI)

    Broniarz-Press, L.; Ochowiak, M.; Rozanski, J.; Woziwodzki, S.

    2009-09-15

    The paper presents the results of experimental studies on atomization of the emulsions flowing through twin-fluid atomizers obtained by the use of the digital microphotography method. The main elements of the test installation were: nozzle, reservoir, pump and measurement units of liquid flow. The photographs were taken by a digital camera with automatic flash at exposure time of 1/8000 s and subsequently analyzed using Image Pro-Plus. The oils used were mineral oils 20-90, 20-70, 20-50 and 20-30. The studies were performed at flow rates of liquid phase changed from 0.0014 to 0.011 (dm{sup 3}/s) and gas phase changed from 0.28 to 1.4 (dm{sup 3}/s), respectively. The analysis of photos shows that the droplets being formed during the liquid atomization have very different sizes. The smallest droplets have diameters of the order of 10 {mu}m. The experimental results showed that the changes in physical properties of a liquid phase lead to the significant changes in the spray characteristics. The analysis of the photos of water and emulsions atomization process showed that the droplet sizes are dependent on gas and liquid flow rates, construction of nozzle and properties of liquid. The differences between characteristics of atomization for water and emulsions have been observed. Analysis of photos on forming the droplets in air-water and air-emulsions systems showed that droplets are bigger in air-emulsion system (at the same value of gas to liquid mass ratio). The values of Sauter mean diameter (SMD) increased with increase of volume fraction of oil in emulsion. The droplet size increased with emulsion viscosity. (author)

  4. Direct measurement of concurrence for atomic two-qubit pure states

    SciTech Connect (OSTI)

    Romero, G.; Lopez, C. E.; Lastra, F.; Retamal, J. C.; Solano, E.

    2007-03-15

    We propose a general scheme to measure the concurrence of an arbitrary two-qubit pure state in atomic systems. The protocol is based on one- and two-qubit operations acting on two available copies of the bipartite system, and followed by a global qubit readout. We show that it is possible to encode the concurrence in the probability of finding all atomic qubits in the ground state. Two possible scenarios are considered: atoms crossing three-dimensional microwave cavities and trapped ion systems.

  5. Laser diagnostics of the energy spectrum of Rydberg states of the lithium-7 atom

    SciTech Connect (OSTI)

    Zelener, B. B. Saakyan, S. A.; Sautenkov, V. A.; Manykin, E. A.; Zelener, B. V.; Fortov, V. E.

    2015-12-15

    The spectra of excited lithium-7 atoms prepared in a magneto-optical trap are studied using a UV laser. The laser diagnostics of the energy of Rydberg atoms is developed based on measurements of the change in resonance fluorescence intensity of ultracold atoms as the exciting UV radiation frequency passes through the Rydberg transition frequency. The energies of various nS configurations are obtained in a broad range of the principal quantum number n from 38 to 165. The values of the quantum defect and ionization energy obtained in experiments and predicted theoretically are discussed.

  6. Micromagic Clock: Microwave Clock Based on Atoms in an Engineered Optical Lattice

    SciTech Connect (OSTI)

    Beloy, K.; Derevianko, A.; Dzuba, V. A.; Flambaum, V. V.

    2009-03-27

    We propose a new class of atomic microwave clocks based on the hyperfine transitions in the ground state of aluminum or gallium atoms trapped in optical lattices. For such elements magic wavelengths exist at which both levels of the hyperfine doublet are shifted at the same rate by the lattice laser field, canceling its effect on the clock transition. A similar mechanism for the magic wavelengths may work in microwave hyperfine transitions in other atoms which have the fine-structure multiplets in the ground state.

  7. Nonlinear spectroscopic effects in quantum gases induced by atom-atom interactions

    SciTech Connect (OSTI)

    Safonov, A. I. Safonova, I. I.; Yasnikov, I. S.

    2013-05-15

    We consider nonlinear spectroscopic effects-interaction-enhanced double resonance and spectrum instability-that appear in ultracold quantum gases owing to collisional frequency shift of atomic transitions and, consequently, due to the dependence of the frequencies on the population of various internal states of the particles. Special emphasis is put to two simplest cases, (a) the gas of two-level atoms and (b) double resonance in a gas of three-level bosons, in which the probe transition frequency remains constant.

  8. Lesson 3 - Atoms and Isotopes | Department of Energy

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

    3 - Atoms and Isotopes Lesson 3 - Atoms and Isotopes You've probably heard people refer to nuclear energy as "atomic energy." Why? Nuclear energy is the energy that is stored in the bonds of atoms, inside the nucleus. Nuclear power plants are designed to capture this energy as heat and convert it to electricity. This lesson looks closely at what atoms are and how atoms store energy. This lesson covers the following topics: Matter Molecules Elements Chemical reaction Periodic table The

  9. Chiral meta-atoms rotated by light

    SciTech Connect (OSTI)

    Liu Mingkai; Powell, David A.; Shadrivov, Ilya V.

    2012-07-16

    We study the opto-mechanical properties of coupled chiral meta-atoms based on a pair of twisted split-ring resonators. By using a simple analytical model in conjunction with the Maxwell stress tensor, we capture insight into the mechanism and find that this structure can be used as a general prototype of subwavelength light-driven actuators over a wide range of frequencies. This coupled structure can provide a strong and tunable torque, and can support different opto-mechanical modes, including uniform rotation, periodically variable rotation and damped oscillations. Our results suggest that chiral meta-atoms are good candidates for creating sub-wavelength motors or wrenches controlled by light.

  10. International Atomic Energy Agency | National Nuclear Security

    National Nuclear Security Administration (NNSA)

    Administration International Atomic Energy Agency Secretary Moniz awards Hutcheon memorial nonproliferation fellowship to Thomas Gray Energy Secretary Ernest Moniz (second from bottom left, clockwise) and Anne Harrington, NNSA deputy administrator for Defense Nuclear Nonproliferation (sitting next to Moniz), discuss Ian Hutcheon's legacy with his wife Nancy (across from Harrington) and daughter Dana Hutcheon Gordon. Energy... DOE/NNSA's Nonproliferation Experts Lead First Workshop on the

  11. Atomization methods for forming magnet powders

    DOE Patents [OSTI]

    Sellers, Charles H.; Branagan, Daniel J.; Hyde, Timothy A.

    2000-01-01

    The invention encompasses methods of utilizing atomization, methods for forming magnet powders, methods for forming magnets, and methods for forming bonded magnets. The invention further encompasses methods for simulating atomization conditions. In one aspect, the invention includes an atomization method for forming a magnet powder comprising: a) forming a melt comprising R.sub.2.1 Q.sub.13.9 B.sub.1, Z and X, wherein R is a rare earth element; X is an element selected from the group consisting of carbon, nitrogen, oxygen and mixtures thereof; Q is an element selected from the group consisting of Fe, Co and mixtures thereof; and Z is an element selected from the group consisting of Ti, Zr, Hf and mixtures thereof; b) atomizing the melt to form generally spherical alloy powder granules having an internal structure comprising at least one of a substantially amorphous phase or a substantially nanocrystalline phase; and c) heat treating the alloy powder to increase an energy product of the alloy powder; after the heat treatment, the alloy powder comprising an energy product of at least 10 MGOe. In another aspect, the invention includes a magnet comprising R, Q, B, Z and X, wherein R is a rare earth element; X is an element selected from the group consisting of carbon, nitrogen, oxygen and mixtures thereof; Q is an element selected from the group consisting of Fe, Co and mixtures thereof; and Z is an element selected from the group consisting of Ti, Zr, Hf and mixtures thereof; the magnet comprising an internal structure comprising R.sub.2.1 Q.sub.13.9 B.sub.1.

  12. First principle thousand atom quantum dot calculations

    SciTech Connect (OSTI)

    Wang, Lin-Wang; Li, Jingbo

    2004-03-30

    A charge patching method and an idealized surface passivation are used to calculate the single electronic states of IV-IV, III-V, II-VI semiconductor quantum dots up to a thousand atoms. This approach scales linearly and has a 1000 fold speed-up compared to direct first principle methods with a cost of eigen energy error of about 20 meV. The calculated quantum dot band gaps are parametrized for future references.

  13. L. James Rainwater and the Atomic Nuclei

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

    L. James Rainwater and the Atomic Nucleus Resources with Additional Information James Rainwater Courtesy AIP Emilio Segre Visual Archives, W. F. Meggers Gallery of Nobel Laureates "During W.W. II, I [James Rainwater] worked ... [on the] Manhattan Project, mainly doing pulsed neutron spectroscopy using the small Columbia cyclotron. ... [Maria Geoppert-Mayer] shell model suggestion in 1949 was a great triumph and fitted my belief that a nuclear shell model should represent a proper approach

  14. AtomsPeace_Dec2003.qxd

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

    Atoms for Peace after 50 Years: The New Challenges and Opportunities December 2003 UCRL-TR-200927 This document was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor the University of California nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or

  15. Do triatomic molecules echo atomic periodicity?

    SciTech Connect (OSTI)

    Hefferlin, R. Barrow, J.

    2015-03-30

    Demonstrations of periodicity among triatomic-molecular spectroscopic constants underscore the role of the periodic law as a foundation of chemistry. The objective of this work is to prepare for another test using vibration frequencies ?{sub 1} of free, ground-state, main-group triatomic molecules. Using data from four data bases and from computation, we have collected ?{sub 1} data for molecules formed from second period atoms.

  16. Classical and quantum chaos in atomic systems

    SciTech Connect (OSTI)

    Delande, D.; Buchleitner, A. [Universite Pierre et Marie Curie, Paris (France)

    1994-12-31

    Atomic systems played a major role in the birth and growth of quantum mechanics. One central idea was to relate the well-known classical motion of the electron of a hydrogen atom--an ellipsis around the nucleus--to the experimentally observed quantization of the energy levels. This is the aim of the Bohr and Bohr-Sommerfeld models. These simple semiclassical models were unable to make any reliable prediction on the energy spectrum of the next simplest atom, helium. Because of the great success of quantum mechanics, the problem of correspondence between the classical and the quantal dynamics has not received much attention in the last 60 years. The fundamental question is (Gutzwiller, 1990). How can classical mechanics be understood as a limiting case within quantum mechanics? For systems with time-independent one-dimensional dynamics like the harmonic oscillator and the hydrogen atom, the correspondence is well understood. The restriction to such simple cases creates the erroneous impression that the classical behavior of simple systems is entirely comprehensible and easily described. During the last 20 years it has been recognized that this in not true and that a complex behavior can be obtained from simple equations of motion. This usually happens when the motion is chaotic, that is, unpredictable on a long time scale although perfectly deterministic (Henon, 1983). A major problem is that of understanding how the regular or chaotic behavior of the classical system is manifest in its quantum properties, especially in the semiclassical limit. 53 refs., 15 figs., 1 tab.

  17. First AID (Atom counting for Isotopic Determination).

    SciTech Connect (OSTI)

    Roach, J. L.; Israel, K. M.; Steiner, R. E.; Duffy, C. J.; Roench, F. R.

    2002-01-01

    Los Alamos National Laboratory (LANL) has established an in vitro bioassay monitoring program in compliance with the requirements in the Code of Federal Regulations, 10 CFR 835, Occupational Radiation Protection. One aspect of this program involves monitoring plutonium levels in at-risk workers. High-risk workers are monitored using the ultra-sensitive Therrnal Ionization Mass Spectrometry (TIMS) technique to ensure compliance with DOE standards. TIMS is used to measure atom ratios of 239Pua nd 240Puw ith respect to a tracer isotope ('Pu). These ratios are then used to calculate the amount of 239Pu and 240Pup resent. This low-level atom counting technique allows the calculation of the concentration levels of 239Pu and 240Pu in urine for at risk workers. From these concentration levels, dose assessments can be made and worker exposure levels can be monitored. Detection limits for TIMS analysis are on the order of millions of atoms, which translates to activity levels of 150 aCi 239Pua nd 500 aCi for 240Pu. pCi for Our poster presentation will discuss the ultra-sensitive, low-level analytical technique used to measure plutonium isotopes and the data verification methods used for validating isotopic measurements.

  18. The national ignition facility and atomic data

    SciTech Connect (OSTI)

    Crandall, David H.

    1998-07-08

    The National Ignition Facility (NIF) is under construction, capping over 25 years of development of the inertial confinement fusion concept by providing the facility to obtain fusion ignition in the laboratory for the first time. The NIF is a 192 beam glass laser to provide energy controlled in space and time so that a millimeter-scale capsule containing deuterium and tritium can be compressed to fusion conditions. Light transport, conversion of light in frequency, interaction of light with matter in solid and plasma forms, and diagnostics of extreme material conditions on small scale all use atomic data in preparing for use of the NIF. The NIF will provide opportunity to make measurements of atomic data in extreme physical environments related to fusion energy, nuclear weapon detonation, and astrophysics. The first laser beams of NIF should be operational in 2001 and the full facility completed at the end of 2003. NIF is to provide 1.8 megajoule of blue light on fusion targets and is intended to achieve fusion ignition by about the end of 2007. Today's inertial fusion development activities use atomic data to design and predict fusion capsule performance and in non-fusion applications to analyze radiation transport and radiation effects on matter. Conditions investigated involve radiation temperature of hundreds of eV, pressures up to gigabars and time scales of femptoseconds.

  19. The national ignition facility and atomic data

    SciTech Connect (OSTI)

    Crandall, D.H.

    1998-07-01

    The National Ignition Facility (NIF) is under construction, capping over 25 years of development of the inertial confinement fusion concept by providing the facility to obtain fusion ignition in the laboratory for the first time. The NIF is a 192 beam glass laser to provide energy controlled in space and time so that a millimeter-scale capsule containing deuterium and tritium can be compressed to fusion conditions. Light transport, conversion of light in frequency, interaction of light with matter in solid and plasma forms, and diagnostics of extreme material conditions on small scale all use atomic data in preparing for use of the NIF. The NIF will provide opportunity to make measurements of atomic data in extreme physical environments related to fusion energy, nuclear weapon detonation, and astrophysics. The first laser beams of NIF should be operational in 2001 and the full facility completed at the end of 2003. NIF is to provide 1.8 megajoule of blue light on fusion targets and is intended to achieve fusion ignition by about the end of 2007. Today{close_quote}s inertial fusion development activities use atomic data to design and predict fusion capsule performance and in non-fusion applications to analyze radiation transport and radiation effects on matter. Conditions investigated involve radiation temperature of hundreds of eV, pressures up to gigabars and time scales of femptoseconds. {copyright} {ital 1998 American Institute of Physics.}

  20. Atomic layer deposition of nanoporous biomaterials.

    SciTech Connect (OSTI)

    Narayan, R. J.; Adiga, S. P.; Pellin, M. J.; Curtiss, L. A.; Stafslien, S.; Chisholm, B.; Monteiro-Riviere, N. A.; Brigmon, R. L.; Elam, J. W.; Univ. of North Carolina; North Carolina State Univ.; Eastman Kodak Co.; North Dakota State Univ.; SRL

    2010-03-01

    Due to its chemical stability, uniform pore size, and high pore density, nanoporous alumina is being investigated for use in biosensing, drug delivery, hemodialysis, and other medical applications. In recent work, we have examined the use of atomic layer deposition for coating the surfaces of nanoporous alumina membranes. Zinc oxide coatings were deposited on nanoporous alumina membranes using atomic layer deposition. The zinc oxide-coated nanoporous alumina membranes demonstrated antimicrobial activity against Escherichia coli and Staphylococcus aureus bacteria. These results suggest that atomic layer deposition is an attractive technique for modifying the surfaces of nanoporous alumina membranes and other nanostructured biomaterials. Nanoporous alumina, also known as anodic aluminum oxide (AAO), is a nanomaterial that exhibits several unusual properties, including high pore densities, straight pores, small pore sizes, and uniform pore sizes. In 1953, Keller et al. showed that anodizing aluminum in acid electrolytes results in a thick layer of nearly cylindrical pores, which are arranged in a close-packed hexagonal cell structure. More recently, Matsuda & Fukuda demonstrated preparation of highly ordered platinum and gold nanohole arrays using a replication process. In this study, a negative structure of nanoporous alumina was initially fabricated and a positive structure of a nanoporous metal was subsequently fabricated. Over the past fifteen years, nanoporous alumina membranes have been used as templates for growth of a variety of nanostructured materials, including nanotubes, nanowires, nanorods, and nanoporous membranes.

  1. NIC atomic operation unit with caching and bandwidth mitigation

    DOE Patents [OSTI]

    Hemmert, Karl Scott; Underwood, Keith D.; Levenhagen, Michael J.

    2016-03-01

    A network interface controller atomic operation unit and a network interface control method comprising, in an atomic operation unit of a network interface controller, using a write-through cache and employing a rate-limiting functional unit.

  2. One Nanocrystal, Many Faces: Connecting the Atomic Surface Structures...

    Office of Science (SC) Website

    The atomic models are overlaid on the simulated images to illustrate atom positions. The Science When it comes to reducing the toxins released by burning gasoline, coal, or other ...

  3. General Atomics Hot Cell Facility, California, Site Fact Sheet

    Office of Legacy Management (LM)

    General Atomics Hot Cell Facility, California, Site. The U.S. Department of Energy Office ... After an Location of the General Atomics Hot Cell Facility, California, Site A hot cell is ...

  4. An Atomic-Level Understanding of Copper-Based Catalysts

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

    An Atomic-Level Understanding of Copper-Based Catalysts An Atomic-Level Understanding of Copper-Based Catalysts Print Thursday, 05 May 2016 12:20 Copper-based catalysts are widely ...

  5. Signals from dark atom formation in halos (Journal Article) ...

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Search Results Journal Article: Signals from dark atom formation in halos Citation Details In-Document Search Title: Signals from dark atom formation in halos ...

  6. The LANL atomic kinetics modeling effort and its application...

    Office of Scientific and Technical Information (OSTI)

    An on-line version of the codes is available at http:aphysics2.lanl.govtempweb. ATOMIC kinetics modelling code uses the atomic data for LTE or NLTE population kinetics models ...

  7. Dynamical Crystallization in the Dipole Blockade of Ultracold Atoms

    SciTech Connect (OSTI)

    Pohl, T.; Demler, E.; Lukin, M. D.

    2010-01-29

    We describe a method for controlling many-body states in extended ensembles of Rydberg atoms, forming crystalline structures during laser excitation of a frozen atomic gas. Specifically, we predict the existence of an excitation-number staircase in laser excitation of atomic ensembles into Rydberg states. It is shown that such ordered states can be selectively excited by chirped laser pulses, and, via quantum state transfer from atoms to light, be used to create crystalline photonic states.

  8. Lesson 6 - Atoms to Electricity | Department of Energy

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

    6 - Atoms to Electricity Lesson 6 - Atoms to Electricity Most power plants make electricity by boiling water to make steam that turns a turbine. A nuclear power plant works this way, too. At a nuclear power plant, splitting atoms produce the heat to boil the water. This lesson covers Inside the Reactor Heat Pressure Water Fission Control Fuel assemblies Control rods Coolant Pressure vessel Electricity Generation Generator Condenser Cooling tower Lesson 6 - Atoms to Electricity.pptx (9.7 MB) More

  9. SYMMETRY OF THE IBEX RIBBON OF ENHANCED ENERGETIC NEUTRAL ATOM...

    Office of Scientific and Technical Information (OSTI)

    English Subject: 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASYMMETRY; ATOMS; DETECTION; ENERGY DEPENDENCE; HELIOSPHERE; INTERSTELLAR SPACE; KEV RANGE; MAGNETIC FIELDS; PLASMA;...

  10. Atomic Layer Deposition (ALD) Preparation of Noble Metal Catalysts - Energy

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

    National Nuclear Security Administration | (NNSA) Explores Peaceful Uses of Nuclear Explosions Atomic Energy Commission Explores Peaceful Uses of Nuclear Explosions Nevada Test Site, NV As part of the Plowshare program seeking to develop peaceful uses for nuclear explosives, the Atomic Energy Commission conducts the Sedan test at the Nevada Test Site Programs | National Nuclear Security Administration | (NNSA)

    Takes Over Responsibility for all Atomic Energy Programs Atomic Energy

  11. DOE - Office of Legacy Management -- Gen_Atomics

    Office of Legacy Management (LM)

    General Atomics Hot Cell Facility, California, Site A Oakland Operations Office site gen_atomics_map The General Atomics Hot Cell Facility site was a research laboratory formerly operated under the DOE Oakland Operations Office, California. After remediation, the site transferred to the Office of Legacy Management in 2005. The site requires records management and stakeholder support. For more information about the General Atomics Hot Cell

  12. Gosling, The Manhattan Project: Making the Atomic Bomb | Department...

    Energy Savers [EERE]

    Operational Management History Historical Resources History Publications Gosling, The Manhattan Project: Making the Atomic Bomb Gosling, The Manhattan Project: Making...

  13. President Roosevelt Approves Production of Atomic Bomb | National Nuclear

    National Nuclear Security Administration (NNSA)

    Security Administration | (NNSA) Approves Production of Atomic Bomb President Roosevelt Approves Production of Atomic Bomb Washington, DC President Roosevelt approves production of the atomic bomb following receipt of a National Academy of Sciences report determining that a bomb is feasible

  14. Light pulse analysis with a multi-state atom interferometer

    SciTech Connect (OSTI)

    Herrera, I.; Lombardi, P.; Schfer, F.; Petrovic, J.; Cataliotti, F. S.

    2014-12-04

    We present a controllable multi-state cold-atom interferometer that is easy-to-use and fully merged on an atom chip. We demonstrate its applications as a sensor of the fields whose interactions with atoms are state-dependent.

  15. Method of performing MRI with an atomic magnetometer

    DOE Patents [OSTI]

    Savukov, Igor Mykhaylovich; Matlashov, Andrei Nikolaevich; Espy, Michelle A.; Volegov, Petr Lvovich; Kraus, Jr., Robert Henry; Zotev, Vadim Sergeyevich

    2012-11-06

    A method and apparatus are provided for performing an in-situ magnetic resonance imaging of an object. The method includes the steps of providing an atomic magnetometer, coupling a magnetic field generated by magnetically resonating samples of the object through a flux transformer to the atomic magnetometer and measuring a magnetic resonance of the atomic magnetometer.

  16. Method of performing MRI with an atomic magnetometer

    DOE Patents [OSTI]

    Savukov, Igor Mykhaylovich; Matlashov, Andrei Nikolaevich; Espy, Michelle A; Volegov, Petr Lvovich; Kraus, Jr., Robert Henry; Zotev, Vadim Sergeyevich

    2013-08-27

    A method and apparatus are provided for performing an in-situ magnetic resonance imaging of an object. The method includes the steps of providing an atomic magnetometer, coupling a magnetic field generated by magnetically resonating samples of the object through a flux transformer to the atomic magnetometer and measuring a magnetic resonance of the atomic magnetometer.

  17. Determination of Atomic Data Pertinent to the Fusion Energy Program

    SciTech Connect (OSTI)

    Reader, J.

    2013-06-11

    We summarize progress that has been made on the determination of atomic data pertinent to the fusion energy program. Work is reported on the identification of spectral lines of impurity ions, spectroscopic data assessment and compilations, expansion and upgrade of the NIST atomic databases, collision and spectroscopy experiments with highly charged ions on EBIT, and atomic structure calculations and modeling of plasma spectra.

  18. Large-angle illumination STEM: Toward three-dimensional atom-by-atom imaging

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

    Ishikawa, Ryo; Lupini, Andrew R.; Hinuma, Yoyo; Pennycook, Stephen

    2014-11-26

    To completely understand and control materials and their properties, it is of critical importance to determine their atomic structures in all three dimensions. Recent revolutionary advances in electron optics – the inventions of geometric and chromatic aberration correctors as well as electron source monochromators – have provided fertile ground for performing optical depth sectioning at atomic-scale dimensions. In this study we theoretically demonstrate the imaging of top/sub-surface atomic structures and identify the depth of single dopants, single vacancies and the other point defects within materials by large-angle illumination scanning transmission electron microscopy (LAI-STEM). The proposed method also allows us tomore » measure specimen properties such as thickness or three-dimensional surface morphology using observations from a single crystallographic orientation.« less

  19. Atomizing apparatus for making polymer and metal powders and whiskers

    DOE Patents [OSTI]

    Otaigbe, Joshua U.; McAvoy, Jon M.; Anderson, Iver E.; Ting, Jason; Mi, Jia; Terpstra, Robert

    2003-03-18

    Method for making polymer particulates, such as spherical powder and whiskers, by melting a polymer material under conditions to avoid thermal degradation of the polymer material, atomizing the melt using gas jet means in a manner to form atomized droplets, and cooling the droplets to form polymer particulates, which are collected for further processing. Atomization parameters can be controlled to produce polymer particulates with controlled particle shape, particle size, and particle size distribution. For example, atomization parameters can be controlled to produce spherical polymer powders, polymer whiskers, and combinations of spherical powders and whiskers. Atomizing apparatus also is provided for atoomizing polymer and metallic materials.

  20. A Green's function quantum average atom model

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

    Starrett, Charles Edward

    2015-05-21

    A quantum average atom model is reformulated using Green's functions. This allows integrals along the real energy axis to be deformed into the complex plane. The advantage being that sharp features such as resonances and bound states are broadened by a Lorentzian with a half-width chosen for numerical convenience. An implementation of this method therefore avoids numerically challenging resonance tracking and the search for weakly bound states, without changing the physical content or results of the model. A straightforward implementation results in up to a factor of 5 speed-up relative to an optimized orbital based code.

  1. Microwave meta-atom enhanced spintronic rectification

    SciTech Connect (OSTI)

    Gou, Peng; Xi, Fuchun; Qian, Qinbai; Xu, Jie; Gui, Y. S.; Hu, C.-M.; An, Zhenghua

    2015-04-06

    An artificial meta-atom (MA), or alternatively, a plasmonic antenna, has been demonstrated to significantly enhance the microwave spin rectifying photovoltage by more than two orders in magnitude (∼280) in the ferromagnetic resonance regime. The large enhancement is attributed to the unique structure of the MA which magnifies both microwave electric (∼5) and magnetic (∼56) fields in the same near-field spatial region. Our work develops the interdisciplinary direction with artificial and natural magnetism and may find promising applications in high-frequency or opto-spintronic devices and wireless microwave energy harvesting.

  2. Method for producing uranium atomic beam source

    DOE Patents [OSTI]

    Krikorian, Oscar H.

    1976-06-15

    A method for producing a beam of neutral uranium atoms is obtained by vaporizing uranium from a compound UM.sub.x heated to produce U vapor from an M boat or from some other suitable refractory container such as a tungsten boat, where M is a metal whose vapor pressure is negligible compared to that of uranium at the vaporization temperature. The compound, for example, may be the uranium-rhenium compound, URe.sub.2. An evaporation rate in excess of about 10 times that of conventional uranium beam sources is produced.

  3. Electric quadrupole transition probabilities for atomic lithium

    SciTech Connect (OSTI)

    elik, Gltekin; Gke, Yasin; Y?ld?z, Murat

    2014-05-15

    Electric quadrupole transition probabilities for atomic lithium have been calculated using the weakest bound electron potential model theory (WBEPMT). We have employed numerical non-relativistic HartreeFock wavefunctions for expectation values of radii and the necessary energy values have been taken from the compilation at NIST. The results obtained with the present method agree very well with the Coulomb approximation results given by Caves (1975). Moreover, electric quadrupole transition probability values not existing in the literature for some highly excited levels have been obtained using the WBEPMT.

  4. Ruthenium / aerogel nanocomposits via Atomic Layer Deposition

    SciTech Connect (OSTI)

    Biener, J; Baumann, T F; Wang, Y; Nelson, E J; Kucheyev, S O; Hamza, A V; Kemell, M; Ritala, M; Leskela, M

    2006-08-28

    We present a general approach to prepare metal/aerogel nanocomposites via template directed atomic layer deposition (ALD). In particular, we used a Ru ALD process consisting of alternating exposures to bis(cyclopentadienyl)ruthenium (RuCp{sub 2}) and air at 350 C to deposit metallic Ru nanoparticles on the internal surfaces of carbon and silica aerogels. The process does not affect the morphology of the aerogel template and offers excellent control over metal loading by simply adjusting the number of ALD cycles. We also discuss the limitations of our ALD approach, and suggest ways to overcome these.

  5. Experimental estimation of oxidation-induced Si atoms emission on Si(001) surfaces

    SciTech Connect (OSTI)

    Ogawa, Shuichi Tang, Jiayi; Takakuwa, Yuji

    2015-08-15

    Kinetics of Si atoms emission during the oxidation of Si(001) surfaces have been investigated using reflection high energy electron diffraction combined with Auger electron spectroscopy. The area ratio of the 1 × 2 and the 2 × 1 domains on a clean Si(001) surface changed with the oxidation of the surface by Langmuir-type adsorption. This change in the domain ratio is attributed to the emission of Si atoms. We can describe the changes in the domain ratio using the Si emission kinetics model, which states that (1) the emission rate is proportional to the oxide coverage, and (2) the emitted Si atoms migrate on the surface and are trapped at S{sub B} steps. Based on our model, we find experimentally that up to 0.4 ML of Si atoms are emitted during the oxidation of a Si(001) surface at 576 °C.

  6. Robust mesoscopic superposition of strongly correlated ultracold atoms

    SciTech Connect (OSTI)

    Hallwood, David W.; Ernst, Thomas; Brand, Joachim

    2010-12-15

    We propose a scheme to create coherent superpositions of annular flow of strongly interacting bosonic atoms in a one-dimensional ring trap. The nonrotating ground state is coupled to a vortex state with mesoscopic angular momentum by means of a narrow potential barrier and an applied phase that originates from either rotation or a synthetic magnetic field. We show that superposition states in the Tonks-Girardeau regime are robust against single-particle loss due to the effects of strong correlations. The coupling between the mesoscopically distinct states scales much more favorably with particle number than in schemes relying on weak interactions, thus making particle numbers of hundreds or thousands feasible. Coherent oscillations induced by time variation of parameters may serve as a 'smoking gun' signature for detecting superposition states.

  7. The Atomic Safety and Licensing Board Panel

    SciTech Connect (OSTI)

    1998-03-01

    Through the Atomic Energy Act, Congress made is possible for the public to get a full and fair hearing on civilian nuclear matters. Individuals who are directly affected by any licensing action involving a facility producing or utilizing nuclear materials may participate in a formal hearing, on the record, before independent judges on the Atomic Safety and Licensing Board Panel (ASLBP or Panel). Frequently, in deciding whether a license, permit, amendment, or extension should be granted to a particular applicant, the Panel members must be more than mere umpires. If appropriate, they are authorized to go beyond the issues the parties place before them in order to identify, explore, and resolve significant questions involving threats to the public health and safety that come to a board`s attention during the proceedings. This brochure explains the purpose of the panel. Also addressed are: type of hearing handled; method of public participation; formality of hearings; high-level waste; other panel responsibilities and litigation technology.

  8. New directions in optical atomic spectrometry

    SciTech Connect (OSTI)

    de Galan, L.

    1986-05-01

    Soon after its invention a successful method of analysis goes through a phase of rapid growth and exaggerated expectations before it recedes to a more balanced position in the analytical domain. Flame and furnace atomic absorption spectrometry (AAS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES), as we know them now, were introduced 20 to 30 years ago, developed into commercial instruments within a decade after their first description in the scientific literature, and have now reached a state of developmental equilibrium. It is undeniable that these techniques have continued to develop, but recent advances have been largely technical and cosmetic. The emphasis on automation and software has made life much easier and has significantly reduced the demand for manpower, but it has not enlarged the analytical scope of the techniques. Many initial promises have been fulfilled, but some shortcomings persist even today. At this point it would be easy to formulate the ideal method that determines all elements from the sub-parts-per-billion level to the 100% level, simultaneously, with high precision and accuracy, and at minimal cost. Clearly, no single method can possibly match such unrealistic expectations. In this article the author has, therefore, chosen the more modest approach of identifying some weak points in available technology and analyzing possible remedies. In several cases current developments are reviewed, and novel instruments proposed in the literature are evaluated. In other cases, the problems have hardly been addressed and thus may pose a challenge for future research. 10 references, 6 tables.

  9. Low energy neutral atoms from the heliosheath

    SciTech Connect (OSTI)

    Fuselier, S. A.; Allegrini, F.; Dayeh, M. A.; Desai, M.; Lewis, W.; Livadiotis, G.; McComas, D. J. E-mail: fallegrini@swri.edu E-mail: mdesai@swri.edu E-mail: george.livadiotis@swri.org; and others

    2014-04-01

    In the heliosheath beyond the termination shock, low energy (<0.5 keV) neutral atoms are created by charge exchange with interstellar neutrals. Detecting these neutrals from Earth's orbit is difficult because their flux is reduced substantially by ionization losses as they propagate from about 100 to 1 AU and because there are a variety of other signals and backgrounds that compete with this weak signal. Observations from IBEX-Lo and -Hi from two opposing vantage points in Earth's orbit established a lower energy limit of about 0.1 keV on measurements of energetic neutral atoms (ENAs) from the heliosphere and the form of the energy spectrum from about 0.1 to 6 keV in two directions in the sky. Below 0.1 keV, the detailed ENA spectrum is not known, and IBEX provides only upper limits on the fluxes. However, using some assumptions and taking constraints on the spectrum into account, we find indications that the spectrum turns over at an energy between 0.1 and 0.2 keV.

  10. Atoms for Peace after Fifty Years

    SciTech Connect (OSTI)

    Joeck, N; Lehman, R; Vergino, E; Schock, R

    2004-03-15

    President Eisenhower's hopes for nuclear technology still resonate, but the challenges to fulfilling them are much different today. On December 8, 1953, President Eisenhower, returning from his meeting with the leaders of Britain and France at the Bermuda Summit, flew directly to New York to address the United Nations General Assembly. His presentation, known afterwards as the ''Atoms for Peace'' speech, was bold, broad, and visionary. Eisenhower highlighted dangers associated with the further spread of nuclear weapons and the end of the thermonuclear monopoly, but the president also pointed to opportunities. Earlier that year, Stalin had died and the Korean War armistice was signed. Talks on reunification of Austria were about to begin. The speech sought East-West engagement and outlined a framework for reducing nuclear threats to security while enhancing the civilian benefits of nuclear technology. One specific proposal offered to place surplus military fissile material under the control of an ''international atomic energy agency'' to be used for peaceful purposes, especially economic development. Eisenhower clearly recognized the complex interrelationships between different nuclear technologies and the risks and the benefits that accrue from each. The widespread use of civilian nuclear technology and absence of any use of a nuclear weapon during the next half-century reflects success in his approach. Today, the world faces choices about nuclear technology that have their parallels in the Eisenhower calculus and its legacy. Although his specific fissile material proposal was never implemented, his broader themes gave impetus to agreements such as the nuclear Non-Proliferation Treaty (NPT) and institutions such as the International Atomic Energy Agency (IAEA). The resulting governance process has promoted some and restricted other nuclear technology. Perhaps even more influential was Eisenhower's overarching recommendation that we try to reduce the risks and seek

  11. 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

    2011-09-01

    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.

  12. Atomic line emission analyzer for hydrogen isotopes

    DOE Patents [OSTI]

    Kronberg, J.W.

    1993-03-30

    Apparatus for isotopic analysis of hydrogen comprises a low pressure chamber into which a sample of hydrogen is introduced and then exposed to an electrical discharge to excite the electrons of the hydrogen atoms to higher energy states and thereby cause the emission of light on the return to lower energy states, a Fresnel prism made at least in part of a material anomalously dispersive to the wavelengths of interest for dispersing the emitted light, and a photodiode array for receiving the dispersed light. The light emitted by the sample is filtered to pass only the desired wavelengths, such as one of the lines of the Balmer series for hydrogen, the wavelengths of which differ slightly from one isotope to another. The output of the photodiode array is processed to determine the relative amounts of each isotope present in the sample. Additionally, the sample itself may be recovered using a metal hydride.

  13. Friction forces on atoms after acceleration

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

    Intravaia, Francesco; Mkrtchian, Vanik E.; Buhmann, Stefan Yoshi; Scheel, Stefan; Dalvit, Diego A. R.; Henkel, Carsten

    2015-05-12

    The aim of this study is to revisit the calculation of atom–surface quantum friction in the quantum field theory formulation put forward by Barton (2010 New J. Phys. 12 113045). We show that the power dissipated into field excitations and the associated friction force depend on how the atom is boosted from being initially at rest to a configuration in which it is moving at constant velocity (v) parallel to the planar interface. In addition, we point out that there is a subtle cancellation between the one-photon and part of the two-photon dissipating power, resulting in a leading order contributionmore » to the frictional power which goes as v4. These results are also confirmed by an alternative calculation of the average radiation force, which scales as v3.« less

  14. Resonance ionization spectroscopy of zirconium atoms

    SciTech Connect (OSTI)

    Page, R.H.; Dropinski, S.C.; Worden, E.F. Jr.; Stockdale, J.A.D.

    1992-05-01

    We have examined the stepwise-resonant three-photon-ionization spectrum of neutral zirconium atoms using three separately-tunable pulsed visible dye lasers. Lifetimes of even-parity levels (measured with delayed-photoionization technique) range from 10 to 100 nsec. Direct ionization cross sections appear to be less than 10{sup {minus}17} cm{sup 2}; newly-detected autoionizing levels give peak ionization cross sections (inferred from saturation fluences) up to 10{sup {minus}15} cm{sup 2}. Members of Rydberg series converging to the 315 and 1323 cm{sup {minus}1} levels of Zr{sup +} were identified. ``Clumps`` of autoionizing levels are thought to be due to Rydberg-valence mixing.

  15. Atomic line emission analyzer for hydrogen isotopes

    DOE Patents [OSTI]

    Kronberg, James W.

    1993-01-01

    Apparatus for isotopic analysis of hydrogen comprises a low pressure chamber into which a sample of hydrogen is introduced and then exposed to an electrical discharge to excite the electrons of the hydrogen atoms to higher energy states and thereby cause the emission of light on the return to lower energy states, a Fresnel prism made at least in part of a material anomalously dispersive to the wavelengths of interest for dispersing the emitted light, and a photodiode array for receiving the dispersed light. The light emitted by the sample is filtered to pass only the desired wavelengths, such as one of the lines of the Balmer series for hydrogen, the wavelengths of which differ slightly from one isotope to another. The output of the photodiode array is processed to determine the relative amounts of each isotope present in the sample. Additionally, the sample itself may be recovered using a metal hydride.

  16. Friction forces on atoms after acceleration

    SciTech Connect (OSTI)

    Intravaia, Francesco; Mkrtchian, Vanik E.; Buhmann, Stefan Yoshi; Scheel, Stefan; Dalvit, Diego A. R.; Henkel, Carsten

    2015-05-12

    The aim of this study is to revisit the calculation of atom–surface quantum friction in the quantum field theory formulation put forward by Barton (2010 New J. Phys. 12 113045). We show that the power dissipated into field excitations and the associated friction force depend on how the atom is boosted from being initially at rest to a configuration in which it is moving at constant velocity (v) parallel to the planar interface. In addition, we point out that there is a subtle cancellation between the one-photon and part of the two-photon dissipating power, resulting in a leading order contribution to the frictional power which goes as v4. These results are also confirmed by an alternative calculation of the average radiation force, which scales as v3.

  17. Atomic line emission analyzer for hydrogen isotopes

    DOE Patents [OSTI]

    Kronberg, J.W.

    1991-05-08

    Apparatus for isotopic analysis of hydrogen comprises a low pressure chamber into which a sample of hydrogen is introduced and then exposed to an electrical discharge to excite the electrons of the hydrogen atoms to higher energy states and thereby cause the emission of light on the return to lower energy states, a Fresnel prism made at least in part of a material anomalously dispersive to the wavelengths of interest for dispersing the emitted light, and a photodiode array for receiving the dispersed light. The light emitted by the sample is filtered to pass only the desired wavelengths, such as one of the lines of the Balmer series for hydrogen, the wavelengths of which differ slightly from one isotope to another. The output of the photodiode array is processed to determine the relative amounts of each isotope present in the sample. Additionally, the sample itself may be recovered using, a metal hydride.

  18. Statistical correlations in the Moshinsky atom

    SciTech Connect (OSTI)

    Laguna, H. G.; Sagar, R. P.

    2011-07-15

    We study the influence of the interparticle and confining potentials on statistical correlation via the correlation coefficient and mutual information in ground and some excited states of the Moshinsky atom in position and momentum space. The magnitude of the correlation between positions and between momenta is equal in the ground state. In excited states, the correlation between the momenta of the particles is greater than between their positions when they interact through an attractive potential whereas for repulsive interparticle potentials the opposite is true. Shannon entropies, and their sums (entropic formulations of the uncertainty principle), are also analyzed, showing that the one-particle entropy sum is dependent on the interparticle potential and thus able to detect the correlation between particles.

  19. Strongly driven one-atom laser and decoherence monitoring

    SciTech Connect (OSTI)

    Lougovski, P.; Casagrande, F.; Lulli, A.; Solano, E.

    2007-09-15

    We propose the implementation of a strongly driven one-atom laser, based on the off-resonant interaction of a three-level atom in {lambda} configuration with a single cavity mode and three laser fields. We show that the system can be described equivalently by a two-level atom resonantly coupled to the cavity and driven by a strong effective coherent field. The effective dynamics can be solved exactly, including a thermal field bath, allowing an analytical description of field statistics and entanglement properties. We also show the possible generation of quantum superposition (Schroedinger cat) states for the whole atom-field system and for the field alone after atomic measurement. We propose a way to monitor the system decoherence by measuring atomic populations. Finally, we confirm the validity of our model through numerical solutions.

  20. Light atom quantum oscillations in UC and US

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

    Yiu, Yuen; Aczel, Adam A.; Granroth, Garrett E.; Abernathy, Douglas L.; Stone, Matthew B.; Buyers, W. J. L.; Lin, J. Y. Y.; Samolyuk, German D.; Stocks, George Malcolm; Nagler, Stephen E.

    2016-01-01

    High energy vibrational scattering in the binary systems UC and US is measured using time-of-flight inelastic neutron scattering. A clear set of well-defined peaks equally separated in energy is observed in UC, corresponding to harmonic oscillations of the light C atoms in a cage of heavy U atoms. The scattering is much weaker in US and only a few oscillator peaks are visible. We show how the difference between the materials can be understood by considering the neutron scattering lengths and masses of the lighter atoms. Monte Carlo ray tracing is used to simulate the scattering, with near quantitative agreementmore » with the data in UC, and some differences with US. The possibility of observing anharmonicity and anisotropy in the potentials of the light atoms is investigated in UC. Lastly, the observed data is well accounted for by considering each light atom as a single atom isotropic quantum harmonic oscillator.« less

  1. Light atom quantum oscillations in UC and US

    SciTech Connect (OSTI)

    Yiu, Yuen; Aczel, Adam A.; Granroth, Garrett E.; Abernathy, Douglas L.; Stone, Matthew B.; Buyers, W. J. L.; Lin, J. Y. Y.; Samolyuk, German D.; Stocks, George Malcolm; Nagler, Stephen E.

    2016-01-01

    High energy vibrational scattering in the binary systems UC and US is measured using time-of-flight inelastic neutron scattering. A clear set of well-defined peaks equally separated in energy is observed in UC, corresponding to harmonic oscillations of the light C atoms in a cage of heavy U atoms. The scattering is much weaker in US and only a few oscillator peaks are visible. We show how the difference between the materials can be understood by considering the neutron scattering lengths and masses of the lighter atoms. Monte Carlo ray tracing is used to simulate the scattering, with near quantitative agreement with the data in UC, and some differences with US. The possibility of observing anharmonicity and anisotropy in the potentials of the light atoms is investigated in UC. Lastly, the observed data is well accounted for by considering each light atom as a single atom isotropic quantum harmonic oscillator.

  2. Hard probes of strongly-interacting atomic gases

    SciTech Connect (OSTI)

    Nishida, Yusuke

    2012-06-18

    We investigate properties of an energetic atom propagating through strongly interacting atomic gases. The operator product expansion is used to systematically compute a quasiparticle energy and its scattering rate both in a spin-1/2 Fermi gas and in a spinless Bose gas. Reasonable agreement with recent quantum Monte Carlo simulations even at a relatively small momentum k/kF > 1.5 indicates that our large-momentum expansions are valid in a wide range of momentum. We also study a differential scattering rate when a probe atom is shot into atomic gases. Because the number density and current density of the target atomic gas contribute to the forward scattering only, its contact density (measure of short-range pair correlation) gives the leading contribution to the backward scattering. Therefore, such an experiment can be used to measure the contact density and thus provides a new local probe of strongly interacting atomic gases.

  3. Sixteenth International Conference on the physics of electronic and atomic collisions

    SciTech Connect (OSTI)

    Dalgarno, A.; Freund, R.S.; Lubell, M.S.; Lucatorto, T.B.

    1989-01-01

    This report contains abstracts of papers on the following topics: photons, electron-atom collisions; electron-molecule collisions; electron-ion collisions; collisions involving exotic species; ion- atom collisions, ion-molecule or atom-molecule collisions; atom-atom collisions; ion-ion collisions; collisions involving rydberg atoms; field assisted collisions; collisions involving clusters and collisions involving condensed matter.

  4. US Energy Secretary Samuel Bodman and Russian Atomic Energy Director

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

    Alexander Rumyantsev Discuss Bratislava Agreement | Department of Energy US Energy Secretary Samuel Bodman and Russian Atomic Energy Director Alexander Rumyantsev Discuss Bratislava Agreement US Energy Secretary Samuel Bodman and Russian Atomic Energy Director Alexander Rumyantsev Discuss Bratislava Agreement May 24, 2005 - 12:51pm Addthis US Energy Secretary Samuel Bodman (right) and Russian Atomic Energy Director Alexander Rumyantsev discuss progress in achieving the Bratislava Nuclear

  5. Iowa Powder Atomization Technologies, Inc. | Department of Energy

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

    Iowa Powder Atomization Technologies, Inc. America's Next Top Energy Innovator Challenge 6067 likes Iowa Powder Atomization Technologies, Inc. Ames Laboratory Iowa Powder Atomization Technologies, Inc. (IPAT) aims to become a leading domestic titanium powder producer allowing for a paradigm shift in the cost of titanium powders for metal injection molding (MIM) feedstock. Decreasing this cost will create vast opportunities for aerospace, military, biomedical, and consumer applications. Titanium

  6. Secretary Chu Addresses the International Atomic Energy Agency General

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

    Conference | Department of Energy Addresses the International Atomic Energy Agency General Conference Secretary Chu Addresses the International Atomic Energy Agency General Conference September 20, 2010 - 12:00am Addthis Washington, DC - U.S. Energy Secretary Steven Chu addressed the International Atomic Energy Agency's 54th General Conference today in Vienna. His prepared remarks are below: Thank you, Ambassador Enkhsaikhan. Congratulations on your election as President of this Conference.

  7. General Atomics Compliance Order, October 6, 1995 Summary

    Office of Environmental Management (EM)

    General Atomics Agreement Name General Atomics Compliance Order, October 6, 1995 HWCA 95/96-017 State California Agreement Type Compliance Agreement Legal Driver(s) FFCAct Scope Summary Address LDR requirements pertaining to storage and treatment of covered waste at General Atomics Parties DOE; State of California Environmental Protection Agency (Department of Toxic Substances Control) Date 10/6/1995 SCOPE * Address LDR requirements pertaining to storage and treatment of covered waste at General

  8. Publication of New Atomic Bomb Radiation Dosimetry System | Department of

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

    Energy Publication of New Atomic Bomb Radiation Dosimetry System Publication of New Atomic Bomb Radiation Dosimetry System February 27, 2006 Due to recent advances in computer technology, DS02 allows more complicated and detailed calculations than DS86 did, as well as detailed simulations of the atomic bomb explosions and of the radiation's release and dispersal. Many improvements have been made, including dose estimates, with consideration paid to the more detailed shielding conditions of

  9. Indium Oxide Thin Films by Atomic Layer Deposition Using Trimethylindium

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

    and Ozone | Argonne National Laboratory Indium Oxide Thin Films by Atomic Layer Deposition Using Trimethylindium and Ozone Title Indium Oxide Thin Films by Atomic Layer Deposition Using Trimethylindium and Ozone Publication Type Journal Article Year of Publication 2016 Authors Mane, AU, Allen, AJ, Kanjolia, RK, Elam, JW Journal Journal of Physical Chemistry C Volume 120 Start Page 9874 Issue 18 Pagination 10 Date Published 04182016 Abstract We investigated the atomic layer deposition (ALD)

  10. Atomic Energy Act and Related Legislation | Department of Energy

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

    Atomic Energy Act and Related Legislation Atomic Energy Act and Related Legislation Purpose and Organization The purpose of the Atomic Energy Act (42 U.S.C. Sect. 2011 - Sect. 2259) (AEA) is to assure the proper management of source, special nuclear, and byproduct material. The AEA and the statutes that amended it delegate the control of nuclear energy primarily to DOE, the Nuclear Regulatory Commission (NRC) , and the Environmental Protection Agency (EPA). DOE authority extends to: source

  11. Albert Einstein Alerts President Roosevelt of German Atomic Energy...

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

    Atomic Energy Program Washington, DC Albert Einstein writes President Franklin D. Roosevelt, alerting the President to the importance of research on nuclear chain reactions ...

  12. UNITED STATES ATOMIC ENERGY COMMISSION OAK RIDGE TENNESSEE THE...

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

    MDDC 869 UNITED STATES ATOMIC ENERGY COMMISSION OAK RIDGE TENNESSEE THE DIFFRACTION OF NEUTRONS BY CRYSTALLINE POWDERS by E. 0. Wollan C. G. Shull Clinton Laboratories Published ...

  13. Kinetics of the Hydrogen Atom Abstraction Reactions from 1-Butanol...

    Office of Scientific and Technical Information (OSTI)

    Theory Matches Experiment and More Citation Details In-Document Search Title: Kinetics of the Hydrogen Atom Abstraction Reactions from 1-Butanol by Hydroxyl Radical: Theory ...

  14. Oscillatory Magneto Conductance in Carbon Atom Wires | Energy...

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

    Our calculation shows a spin valve behavior with the parallel magnetization state between the two Co atoms giving higher conductance than the respective antiparallel magnetization ...

  15. Multi-component Cu-Strengthened Steel Welding Simulations: Atom...

    Office of Scientific and Technical Information (OSTI)

    Steel Welding Simulations: Atom Probe Tomography and Synchrotron X-ray Diffraction Analyses Citation Details In-Document Search Title: Multi-component Cu-Strengthened Steel Welding ...

  16. Fe Atomic Data for Non-equilibrium Ionization Plasmas Eriksen...

    Office of Scientific and Technical Information (OSTI)

    Fe Atomic Data for Non-equilibrium Ionization Plasmas Eriksen, Kristoffer A. Los Alamos National Laboratory; Fontes, Christopher J. Los Alamos National Laboratory; Colgan,...

  17. Ultrasonic-Based Mode-Synthesizing Atomic Force Microscopy -...

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

    Only ultrasonic-based atomic force microscopy in the industry Sufficiently flexible for compatibility with spectroscopic approaches such as Raman spectroscopy Easily adaptable to ...

  18. Sandia Energy - Sandia Chemist Named as an Institute of Atomic...

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

    Named as an Institute of Atomic and Molecular Sciences Advisory Board Member Chemist David Chandler works in Sandia's Transportation Energy Center and the Combustion Research...

  19. Atomic substitution reveals the structural basis for substrate...

    Office of Scientific and Technical Information (OSTI)

    by an adenine DNA glycosylase, Bacillus stearothermophilus MutY, have previously ... Language: ENGLISH Subject: 08 HYDROGEN; ADENINES; ATOMS; BACILLUS; BONDING; CLEAVAGE; DNA; ...

  20. The Manhattan Project: Making the Atomic Bomb. 1999 edition.

    SciTech Connect (OSTI)

    Gosling, F.G.

    1999-01-01

    ``The Manhattan Project: Making the Atomic Bomb`` is a short history of the origins and development of the American atomic bomb program during World War II. Beginning with the scientific developments of the pre-war years, the monograph details the role of the United States government in conducting a secret, nationwide enterprise that took science from the laboratory and into combat with an entirely new type of weapon. The monograph concludes with a discussion of the immediate postwar period, the debate over the Atomic Energy Act of 1946, and the founding of the Atomic Energy Commission.

  1. Aided by Simulations, Scientists Observe Atomic Collapse State

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

    Collapse State Observed Aided by Simulations, Scientists Observe Atomic Collapse State Quantum Mechanics Prediction Confirmed in Graphene Using NERSC's Hopper April 26, 2013...

  2. Atomic Layer Deposition for Stabilization of Amorphous Silicon...

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

    More Documents & Publications Nanostructured Metal Oxide Anodes Atomic Layer Deposition for Stabilization of Silicon Anodes Development of Industrially Viable Battery Electrode ...

  3. Isotropically sensitive optical filter employing atomic resonance transitions

    DOE Patents [OSTI]

    Marling, John B.

    1981-01-01

    An ultra-high Q isotropically sensitive optical filter or optical detector employing atomic resonance transitions. More specifically, atomic resonance transitions utilized in conjunction with two optical bandpass filters provide an optical detector having a wide field of view (.about.2.pi. steradians) and very narrow acceptance bandwidth approaching 0.01 A. A light signal to be detected is transmitted through an outer bandpass filter into a resonantly absorbing atomic vapor, the excited atomic vapor then providing a fluorescence signal at a different wavelength which is transmitted through an inner bandpass filter. The outer and inner bandpass filters have no common transmission band, thereby resulting in complete blockage of all optical signals that are not resonantly shifted in wavelength by the intervening atomic vapor. Two embodiments are disclosed, one in which the light signal raises atoms contained in the atomic vapor from the ground state to an excited state from which fluorescence occurs, and the other in which a pump laser is used to raise the atoms in the ground state to a first excited state from which the light signal then is resonantly absorbed, thereby raising the atoms to a second excited state from which fluorescence occurs. A specific application is described in which an optical detector according to the present invention can be used as an underwater detector for light from an optical transmitter which could be located in an orbiting satellite.

  4. Trimodal Tapping Mode Atomic Force Microscopy. Simultaneous 4D...

    Office of Scientific and Technical Information (OSTI)

    Materials This project focused on the development of single-pass multifrequency atomic ... Country of Publication: United States Language: English Subject: 77 NANOSCIENCE AND ...

  5. COLLOQUIUM: Assessing First Wall Materials at the Atomic Scale...

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

    Wall Materials at the Atomic Scale and Energy Writ Large at Princeton Professor Emily Carter Princeton University Colloquium Committee: The Princeton Plasma Physics Laboratory...

  6. Atomic Energy Commission Explores Peaceful Uses of Nuclear Explosions...

    National Nuclear Security Administration (NNSA)

    Explosions Nevada Test Site, NV As part of the Plowshare program seeking to develop peaceful uses for nuclear explosives, the Atomic Energy Commission conducts the Sedan test ...

  7. Big, Deep, and Smart Data in Energy Materials Research: Atomic...

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

    Big, Deep, and Smart Data in Energy Materials Research: Atomic View on Materials Functionalities Event Sponsor: Computing, Environment, and Life Sciences Seminar Start Date: Sep 22...

  8. Hydrogen transport diagnostics by atomic and molecular emission...

    Office of Scientific and Technical Information (OSTI)

    Hydrogen transport diagnostics by atomic and molecular emission line profiles simultaneously measured for large helical device Citation Details In-Document Search Title: Hydrogen ...

  9. SYMMETRY OF THE IBEX RIBBON OF ENHANCED ENERGETIC NEUTRAL ATOM...

    Office of Scientific and Technical Information (OSTI)

    HELIOSPHERE; INTERSTELLAR SPACE; KEV RANGE; MAGNETIC FIELDS; PLASMA; REFLECTION; SUN; SYMMETRY The circular ribbon of enhanced energetic neutral atom (ENA) emission...

  10. Institute for Atom-Efficient Chemical Transformations - Materials...

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

    of which are crucial for evaluating performance in the proverbial vacuum. Using atomic layer deposition (ALD), researchers can create highly specific nanobowls, controlling...

  11. Analytical evaluation of atomic form factors: Application to Rayleigh scattering

    SciTech Connect (OSTI)

    Safari, L.; Santos, J. P.; Amaro, P.; Jnkl, K.; Fratini, F.

    2015-05-15

    Atomic form factors are widely used for the characterization of targets and specimens, from crystallography to biology. By using recent mathematical results, here we derive an analytical expression for the atomic form factor within the independent particle model constructed from nonrelativistic screened hydrogenic wave functions. The range of validity of this analytical expression is checked by comparing the analytically obtained form factors with the ones obtained within the Hartee-Fock method. As an example, we apply our analytical expression for the atomic form factor to evaluate the differential cross section for Rayleigh scattering off neutral atoms.

  12. Storage and retrieval of thermal light in warm atomic vapor ...

    Office of Scientific and Technical Information (OSTI)

    Country of Publication: United States Language: English Subject: 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ATOMS; CORRELATION FUNCTIONS; INTERFEROMETRY; OPACITY; PHOTON ...

  13. Method of trivalent chromium concentration determination by atomic spectrometry

    DOE Patents [OSTI]

    Reheulishvili, Aleksandre N.; Tsibakhashvili, Neli Ya.

    2006-12-12

    A method is disclosed for determining the concentration of trivalent chromium Cr(III) in a sample. The addition of perchloric acid has been found to increase the atomic chromium spectrometric signal due to Cr(III), while leaving the signal due to hexavalent chromium Cr(VI) unchanged. This enables determination of the Cr(III) concentration without pre-concentration or pre-separation from chromium of other valences. The Cr(III) concentration may be measured using atomic absorption spectrometry, atomic emission spectrometry or atomic fluorescence spectrometry.

  14. International Atomic Energy Agency Feed | Open Energy Information

    Open Energy Info (EERE)

    Institute (WRI) World Watch Institute International Atomic Energy Agency Feed Nuclear Safety is a Continuum, not a Final Destination

    "There's this continuum with regard...

  15. Atomic Layer Deposition and in Situ Characterization of Ultraclean...

    Office of Scientific and Technical Information (OSTI)

    Hydroxide Citation Details In-Document Search Title: Atomic Layer Deposition and in Situ Characterization of Ultraclean Lithium Oxide and Lithium Hydroxide Authors: Kozen,...

  16. LSU EFRC - Center for Atomic Level Catalyst Design

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

    space control Our Mission Statement space control "Building Effective Catalysts from First Principles: Computational Catalysis and Atomic-Level Synthesis" The mission of LSU's ...

  17. Connecting Three Atomic Layers Puts Semiconducting Science on...

    Office of Science (SC) Website

    the linear junction region along the triangular interface produces enhanced light emission (red region). The Science A new semiconducting material that is only three atomic...

  18. Control Heterogeneous Catalysis at Atomic and Electronic-level...

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

    Control Heterogeneous Catalysis at Atomic and Electronic-level Using Intermetallic Compounds Precious metals and metal alloys are important heterogeneous catalysts for renewable...

  19. Atomic weight and isotopic abundance data analysis 1993

    SciTech Connect (OSTI)

    Holden, N.E.

    1993-08-01

    Literature on isotopic abundance measurements and their variation in nature have been reviewed for impact on standard atomic weight values and associated uncertainties for recent measurements.

  20. President Roosevelt Approves Production of Atomic Bomb | National...

    National Nuclear Security Administration (NNSA)

    Approves Production of Atomic Bomb | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing Proliferation...

  1. Exploiting Universality in Atoms with Large Scattering Lengths

    SciTech Connect (OSTI)

    Braaten, Eric

    2012-05-31

    The focus of this research project was atoms with scattering lengths that are large compared to the range of their interactions and which therefore exhibit universal behavior at sufficiently low energies. Recent dramatic advances in cooling atoms and in manipulating their scattering lengths have made this phenomenon of practical importance for controlling ultracold atoms and molecules. This research project was aimed at developing a systematically improvable method for calculating few-body observables for atoms with large scattering lengths starting from the universal results as a first approximation. Significant progress towards this goal was made during the five years of the project.

  2. ATOMIC BEAM STUDIES IN THE RHIC H-JET POLARIMETER.

    SciTech Connect (OSTI)

    MAKDISI,Y.; ZELENSKI,A.; GRAHAM,D.; KOKHANOVSKI,S.; MAHLER,G.; NASS,A.; RITTER,J.; ZUBETS,V.; ET AL.

    2005-01-28

    The results of atomic beam production studies are presented. Improved cooling of the atoms before jet formation in the dissociator cold nozzle apparently reduces the atomic beam velocity spread and improves beam focusing conditions. A carefully designed sextupole separating (and focusing) magnet system takes advantage of the high brightness source. As a result a record beam intensity of a 12.4 {center_dot} 10{sup 16} atoms/s was obtained within 10 mm acceptance at the collision point. The results of the polarization dilution factor measurements (by the hydrogen molecules at the collision point) are also presented.

  3. Hydrogen atom temperature measured with wavelength-modulated...

    Office of Scientific and Technical Information (OSTI)

    Subject: 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ABSORPTION SPECTROSCOPY; ATOMS; DIODE-PUMPED SOLID STATE LASERS; DISTRIBUTION ...

  4. Gosling, The Manhattan Project: Making the Atomic Bomb | Department of

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

    Energy Gosling, The Manhattan Project: Making the Atomic Bomb Gosling, The Manhattan Project: Making the Atomic Bomb F.G. Gosling. The Manhattan Project: Making the Atomic Bomb. DOE/MA-0002 Revised. Washington, D.C.: Department of Energy, 2010. 115 pp., with 38 pp. photo gallery). From the Forward to the 2010 Edition: "In a national survey at the turn of the millennium, journalists and historians ranked the dropping of the atomic bomb and the surrender of Japan to end the Second World

  5. The Evolution in Pu Nanocluster Electronic Structure: from Atomicity...

    Office of Scientific and Technical Information (OSTI)

    Conference: The Evolution in Pu Nanocluster Electronic Structure: from Atomicity to Three Dimensionality Citation Details In-Document Search Title: The Evolution in Pu Nanocluster ...

  6. President Eisenhower Delivers Atoms for Peace Speech | National...

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

    Eisenhower Delivers Atoms for Peace Speech | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing...

  7. The Harnessed Atom - Student Edition | Department of Energy

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

    Edition The Harnessed Atom is a middle school science, technology, engineering, and math (STEM) curriculum extension that focuses on nuclear science and energy. It is designed...

  8. The Electronic Structure of Oxygen Atom Vacancy and Hydroxyl...

    Office of Scientific and Technical Information (OSTI)

    Title: The Electronic Structure of Oxygen Atom Vacancy and Hydroxyl Impurity Defects on Titanium Dioxide (110) Surface Introducing a charge into a solid such as a metal oxide ...

  9. DOE - Office of Legacy Management -- Gen_Atomics

    Office of Legacy Management (LM)

    for the GA Project Files to the Office of Legacy Management (DOE memorandum) September 3, ... April 2002 General Atomics Final Drum of Legacy Mixed Wastes (Department of Toxic ...

  10. Isotropically sensitive optical filter employing atomic resonance transitions

    DOE Patents [OSTI]

    Marling, J.B.

    An ultra-high Q isotropically sensitive optical filter or optical detector is disclosed employing atomic resonance transitions. More specifically, atomic resonance transitions utilized in conjunction with two optical bandpass filters provide an optical detector having a wide field of view (approx. 2 ..pi.. steradians) and very narrow acceptance bandwidth approaching 0.01A. A light signal to be detected is transmitted through an outer bandpass filter into a resonantly absorbing atomic vapor, the excited atomic vapor than providing a fluorescence signal at a different wavelength which is transmitted through an inner bandpass filters have no common transmission band, therby resulting in complete blockage of all optical signals that are not resonantly shifted in wavelength by the intervening atomic vapor. Two embodiments are disclosed, one in which the light signal raises atoms contained in the atomic vapor from the ground state to an excited state from which fluorescence occurs, and the other in which a pump laser is used to raise the atoms in the ground state to a first excited state from which the light signal then is resonantly absorbed, thereby raising the atoms to a second excited state from which fluorescence occurs. A specific application is described in which an optical detector according to the present invention can be located in an orbiting satellite.

  11. Simulations of Kinetic Events at the Atomic Scale

    Broader source: Energy.gov [DOE]

    Presentation on the Simulations of Kinetic Events at the Atomic Scale given at the DOE Theory Focus Session on Hydrogen Storage Materials on May 18, 2006.

  12. Electroless Atomic Layer Deposition: A Scalable Approach to Surface...

    Office of Scientific and Technical Information (OSTI)

    Title: Electroless Atomic Layer Deposition: A Scalable Approach to Surface Modified Metal Powders. Abstract not provided. Authors: Cappillino, Patrick ; Robinson, David ; El Gabaly ...

  13. Atomic-Scale Mapping of Thermoelectric Power on Graphene: Role...

    Office of Scientific and Technical Information (OSTI)

    Mapping of Thermoelectric Power on Graphene: Role of Defects and Boundaries Citation Details In-Document Search Title: Atomic-Scale Mapping of Thermoelectric Power on ...

  14. Discovery of novel hydrogen storage materials: an atomic scale...

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

    Discovery of novel hydrogen storage materials: an atomic scale computational approach Home Author: C. Wolverton, D. J. Siegel, A. R. Akbarzadeh, V. Ozolins Year: 2008 Abstract:...

  15. Atomic-scale chemical quantification of oxide interfaces using...

    Office of Scientific and Technical Information (OSTI)

    Atomic-scale chemical quantification of oxide interfaces using energy-dispersive X-ray ... ANTIFERROMAGNETISM; ASYMMETRY; BISMUTH COMPOUNDS; DIFFUSION; EPITAXY; ...

  16. Thermal effects on the stability of excited atoms in cavities

    SciTech Connect (OSTI)

    Khanna, F. C.; Malbouisson, A. P. C.; Malbouisson, J. M. C.; Santana, A. E.

    2010-03-15

    An atom, coupled linearly to an environment, is considered in a harmonic approximation in thermal equilibrium inside a cavity. The environment is modeled by an infinite set of harmonic oscillators. We employ the notion of dressed states to investigate the time evolution of the atom initially in the first excited level. In a very large cavity (free space) for a long elapsed time, the atom decays and the value of its occupation number is the physically expected one at a given temperature. For a small cavity the excited atom never completely decays and the stability rate depends on temperature.

  17. REFRACTORY MATERIALS IN ATOMIC PILES. (Journal Article) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    REFRACTORY MATERIALS IN ATOMIC PILES. Citation Details ... OSTI Identifier: 4574486 Resource Type: Journal Article ... Receipt Date: 31-DEC-68 Research Org: Originating Research ...

  18. Ribosome research in atomic detail offers potential insights...

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

    A groundbreaking study of the human ribosome is revealing that the tiny molecular machine ... atomic-resolution model of the human ribosome consistent with microscopy. A). ...

  19. Atomic layer engineering for chemically sharp oxide heterointerfaces...

    Office of Scientific and Technical Information (OSTI)

    Title: Atomic layer engineering for chemically sharp oxide heterointerfaces Authors: Choi, Woo Seok 1 ; Rouleau, Christopher M 1 ; Seo, Sung Seok A 1 ; Eres, Gyula 1 ; Lee, ...

  20. Etalon-induced baseline drift and correction in atom flux sensors based on atomic absorption spectroscopy

    SciTech Connect (OSTI)

    Du, Yingge; Chambers, Scott A.

    2014-10-20

    Atom flux sensors based on atomic absorption (AA) spectroscopy are of significant interest in thin film growth as they can provide unobtrusive, element specific real-time flux sensing and control. The ultimate sensitivity and performance of these sensors are strongly affected by baseline drift. Here we demonstrate that an etalon effect resulting from temperature changes in optical viewport housings is a major source of signal instability, which has not been previously considered, and cannot be corrected using existing methods. We show that small temperature variations in the fused silica viewports can introduce intensity modulations of up to 1.5% which in turn significantly deteriorate AA sensor performance. This undesirable effect can be at least partially eliminated by reducing the size of the beam and tilting the incident light beam off the viewport normal.

  1. Etalon-induced Baseline Drift And Correction In Atom Flux Sensors Based On Atomic Absorption Spectroscopy

    SciTech Connect (OSTI)

    Du, Yingge; Chambers, Scott A.

    2014-10-20

    Atom flux sensors based on atomic absorption (AA) spectroscopy are of significant interest in thin film growth as they can provide unobtrusive, element specific, real-time flux sensing and control. The ultimate sensitivity and performance of the sensors are strongly affected by the long-term and short term baseline drift. Here we demonstrate that an etalon effect resulting from temperature changes in optical viewport housings is a major source of signal instability which has not been previously considered or corrected by existing methods. We show that small temperature variations in the fused silica viewports can introduce intensity modulations of up to 1.5%, which in turn significantly deteriorate AA sensor performance. This undesirable effect can be at least partially eliminated by reducing the size of the beam and tilting the incident light beam off the viewport normal.

  2. The Atomic Vapor Laser Isotope Separation Program

    SciTech Connect (OSTI)

    Not Available

    1992-11-09

    This report provides the finding and recommendations on the audit of the Atomic Vapor Laser Isotope Separation (AVLIS) program. The status of the program was assessed to determine whether the Department was achieving objectives stated in its January 1990 Plan for the Demonstration, Transition and Deployment of AVLIS Technology. Through Fiscal Year 1991, the Department had spent about $1.1 billion to develop AVLIS technology. The January 1990 plan provided for AVLIS to be far enough along by September to enable the Department to make a determination of the technical and economic feasibility of deployment. However, the milestones needed to support that determination were not met. An estimated $550 million would be needed to complete AVLIS engineering development and related testing prior to deployment. The earliest possible deployment date has slipped to beyond the year 2000. It is recommended that the Department reassess the requirement for AVLIS in light of program delays and changes that have taken place in the enrichment market since January 1990. Following the reassessment, a decision should be made to either fully support and promote the actions needed to complete AVLIS development or discontinue support for the program entirely. Management`s position is that the Department will successfully complete the AVLIS technology demonstration and that the program should continue until it can be transferred to a Government corporation. Although the auditors recognize that AVLIS may be transferred, there are enough technical and financial uncertainties that a thorough assessment is warranted.

  3. Carbon based thirty six atom spheres

    DOE Patents [OSTI]

    Piskoti, Charles R.; Zettl, Alex K.; Cohen, Marvin L.; Cote, Michel; Grossman, Jeffrey C.; Louie, Steven G.

    2005-09-06

    A solid phase or form of carbon is based on fullerenes with thirty six carbon atoms (C.sub.36). The C.sub.36 structure with D.sub.6h symmetry is one of the two most energetically favorable, and is conducive to forming a periodic system. The lowest energy crystal is a highly bonded network of hexagonal planes of C.sub.36 subunits with AB stacking. The C.sub.36 solid is not a purely van der Waals solid, but has covalent-like bonding, leading to a solid with enhanced structural rigidity. The solid C.sub.36 material is made by synthesizing and selecting out C.sub.36 fullerenes in relatively large quantities. A C.sub.36 rich fullerene soot is produced in a helium environment arc discharge chamber by operating at an optimum helium pressure (400 torr). The C.sub.36 is separated from the soot by a two step process. The soot is first treated with a first solvent, e.g. toluene, to remove the higher order fullerenes but leave the C.sub.36. The soot is then treated with a second solvent, e.g. pyridine, which is more polarizable than the first solvent used for the larger fullerenes. The second solvent extracts the C.sub.36 from the soot. Thin films and powders can then be produced from the extracted C.sub.36. Other materials are based on C.sub.36 fullerenes, providing for different properties.

  4. 2010 Atomic & Molecular Interactions Gordon Research Conference

    SciTech Connect (OSTI)

    Todd Martinez

    2010-07-23

    The Atomic and Molecular Interactions Gordon Conferences is justifiably recognized for its broad scope, touching on areas ranging from fundamental gas phase and gas-condensed matter collision dynamics, to laser-molecule interactions, photophysics, and unimolecular decay processes. The meeting has traditionally involved scientists engaged in fundamental research in gas and condensed phases and those who apply these concepts to systems of practical chemical and physical interest. A key tradition in this meeting is the strong mixing of theory and experiment throughout. The program for 2010 conference continues these traditions. At the 2010 AMI GRC, there will be talks in 5 broadly defined and partially overlapping areas of intermolecular interactions and chemical dynamics: (1) Photoionization and Photoelectron Dynamics; (2) Quantum Control and Molecules in Strong Fields; (3) Photochemical Dynamics; (4) Complex Molecules and Condensed Phases; and (5) Clusters and Reaction Dynamics. These areas encompass many of the most productive and exciting areas of chemical physics, including both reactive and nonreactive processes, intermolecular and intramolecular energy transfer, and photodissociation and unimolecular processes. Gas phase dynamics, van der Waals and cluster studies, laser-matter interactions and multiple potential energy surface phenomena will all be discussed.

  5. Atomic processes in high temperature plasmas

    SciTech Connect (OSTI)

    Hahn, Y.

    1991-07-01

    This is the final report on the project Atomic Processes in High Temperature Plasmas', which has been completed in June 30, 1991. The original contract started in 1978. The dielectronic recombination (DR) rate coefficients were calculated for ions with the number of electrons N = 1, 2, 3, 4, 5, 10, 11, and 12. The result was then used to construct a new and improved rate formula. Other important resonant processes, which are closely related to DR, were also studied to interpret experiments and to test the DR theory. The plasma field and the density effects on the rate coefficients was found to be important, and a consistent correction procedure is being developed. The available data on the DR rates and their accuracy do not yet fully meet the requirement for plasma modeling; there are serious gaps in the available data, and the currently adopted theoretical procedure needs improvements. Critical assessment of the current status of the DR problem is presented, and possible future work needed is summarized.

  6. Atomic Energy Commission Explores Peaceful Uses of Nuclear Explosions |

    National Nuclear Security Administration (NNSA)

    National Nuclear Security Administration | (NNSA) Explores Peaceful Uses of Nuclear Explosions Atomic Energy Commission Explores Peaceful Uses of Nuclear Explosions Nevada Test Site, NV As part of the Plowshare program seeking to develop peaceful uses for nuclear explosives, the Atomic Energy Commission conducts the Sedan test at the Nevada Test Site

  7. Structures of 38-atom gold-platinum nanoalloy clusters

    SciTech Connect (OSTI)

    Ong, Yee Pin; Yoon, Tiem Leong; Lim, Thong Leng

    2015-04-24

    Bimetallic nanoclusters, such as gold-platinum nanoclusters, are nanomaterials promising wide range of applications. We perform a numerical study of 38-atom gold-platinum nanoalloy clusters, Au{sub n}Pt{sub 38−n} (0 ≤ n ≤ 38), to elucidate the geometrical structures of these clusters. The lowest-energy structures of these bimetallic nanoclusters at the semi-empirical level are obtained via a global-minimum search algorithm known as parallel tempering multi-canonical basin hopping plus genetic algorithm (PTMBHGA), in which empirical Gupta many-body potential is used to describe the inter-atomic interactions among the constituent atoms. The structures of gold-platinum nanoalloy clusters are predicted to be core-shell segregated nanoclusters. Gold atoms are observed to preferentially occupy the surface of the clusters, while platinum atoms tend to occupy the core due to the slightly smaller atomic radius of platinum as compared to gold’s. The evolution of the geometrical structure of 38-atom Au-Pt clusters displays striking similarity with that of 38-atom Au-Cu nanoalloy clusters as reported in the literature.

  8. Efficient detection of photons emitted from fast moving atoms

    SciTech Connect (OSTI)

    Lehmann, Bernhard; Quintel, Harald; Ludin, Andrea; Tschannen, Thomas

    1997-01-15

    Metastable atoms of krypton and photons from a tunable cw infrared diode laser at 812 nm meet in counterpropagating beams. A photomultiplier mounted perpendicular to the beams detects photons reemitted from the passing atoms. Multiple diffuse reflections from a thermoplastics tube are used to achieve the high collection efficiency necessary for photon burst detection.

  9. Induce magnetism into silicene by embedding transition-metal atoms

    SciTech Connect (OSTI)

    Sun, Xiaotian; Wang, Lu E-mail: yyli@suda.edu.cn; Lin, Haiping; Hou, Tingjun; Li, Youyong E-mail: yyli@suda.edu.cn

    2015-06-01

    Embedding transition-metal (TM) atoms into nonmagnetic nanomaterials is an efficient way to induce magnetism. Using first-principles calculations, we systematically investigated the structural stability and magnetic properties of TM atoms from Sc to Zn embedded into silicene with single vacancy (SV) and double vacancies (DV). The binding energies for different TM atoms correlate with the TM d-shell electrons. Sc, Ti, and Co show the largest binding energies of as high as 6 eV, while Zn has the lowest binding energy of about 2 eV. The magnetic moment of silicene can be modulated by embedding TM atoms from V to Co, which mainly comes from the 3d orbitals of TM along with partly contributions from the neighboring Si atoms. Fe atom on SV and Mn atom on DV have the largest magnetic moment of more than 3 μB. In addition, we find that doping of N or C atoms on the vacancy site could greatly enhance the magnetism of the systems. Our results provide a promising approach to design silicene-based nanoelectronics and spintronics device.

  10. Problems with Accurate Atomic Lfetime Measurements of Multiply Charged Ions

    SciTech Connect (OSTI)

    Trabert, E

    2009-02-19

    A number of recent atomic lifetime measurements on multiply charged ions have reported uncertainties lower than 1%. Such a level of accuracy challenges theory, which is a good thing. However, a few lessons learned from earlier precision lifetime measurements on atoms and singly charged ions suggest to remain cautious about the systematic errors of experimental techniques.

  11. THE ATOMIC WEIGHTS COMMISSION AND ISOTOPIC ABUNDANCE RATIO DETERMINATIONS.

    SciTech Connect (OSTI)

    HOLDEN, N.E.

    2005-08-07

    Following Thomson's discovery of stable isotopes in non-radioactive chemical elements, the derivation of atomic weight values from mass spectrometric measurements of isotopic abundance ratios moved very slowly. Forty years later, only 3 1/2 % of the recommended values were based on mass spectrometric measurements and only 38% in the first half century. It might be noted that two chemical elements (tellurium and mercury) are still based on chemical measurements, where the atomic weight value calculated from the relative isotopic abundance measurement either agrees with the value from the chemical measurement or the atomic weight value calculated from the relative isotopic abundance measurement falls within the uncertainty of the chemical measurement of the atomic weight. Of the 19 chemical elements, whose atomic weight is based on non-corrected relative isotopic abundance measurements, five of these are two isotope systems (indium, iridium, lanthanum, lutetium and tantalum) and one is a three-isotope system (oxygen).

  12. ATOMIC CARBON IN THE UPPER ATMOSPHERE OF TITAN

    SciTech Connect (OSTI)

    Zhang, X.; Yung, Y. L.; Ajello, J. M.

    2010-01-01

    The atomic carbon emission C I line feature at 1657 A ({sup 3} P {sup 0} {sub J}-{sup 3} P{sub J} ) in the upper atmosphere of Titan is first identified from the airglow spectra obtained by the Cassini Ultra-violet Imaging Spectrograph. A one-dimensional photochemical model of Titan is used to study the photochemistry of atomic carbon on Titan. Reaction between CH and atomic hydrogen is the major source of atomic carbon, and reactions with hydrocarbons (C{sub 2}H{sub 2} and C{sub 2}H{sub 4}) are the most important loss processes. Resonance scattering of sunlight by atomic carbon is the dominant emission mechanism. The emission intensity calculations based on model results show good agreement with the observations.

  13. Conduction in alumina with atomic scale copper filaments

    SciTech Connect (OSTI)

    Xu, Xu; Liu, Jie; Anantram, M. P.

    2014-10-28

    The conductance of atomic scale filaments with three and seven Cu atoms in ?-alumina are calculated using ab initio density functional theory. We find that the filament with 3 Cu atoms is sufficient to increase the conductance of 1.3?nm thick alumina film by more than 10{sup 3} times in linear response. As the applied voltage increases, the current quickly saturates and differential resistance becomes negative. Compared to the filament with three Cu atoms, while the conductance of the filament with seven Cu atoms is comparable in linear response, they carry as much as twenty times larger current at large biases. The electron transport is analyzed based on local density of states, and the negative differential resistance in the seven Cu filaments occurs due to their narrow bandwidth.

  14. Remarkable NO oxidation on single supported platinum atoms

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

    Narula, Chaitanya K.; Allard, Lawrence F.; Stocks, G. M.; Moses-DeBusk, Melanie

    2014-11-28

    Our first-principles density functional theoretical modeling suggests that NO oxidation is feasible on fully oxidized single θ-alumina-supported platinum atoms via a modified Langmuir-Hinshelwood pathway. This is in contrast to the known decrease in NO oxidation activity of supported platinum with decreasing Pt particle size believed to be due to increased platinum oxidation. In order to validate our theoretical study, we evaluated single θ-Al2O3-supported platinum atoms and found them to exhibit remarkable NO oxidation activity. A comparison of turnover frequencies (TOF) of single supported Pt atoms with those of platinum particles for NO oxidation shows that single supported Pt atoms aremore » as active as fully formed platinum particles. The overall picture of NO oxidation on supported Pt is that NO oxidation activity decreases with decreasing Pt particle size but accelerates when Pt is present only as single atoms.« less

  15. Probing the Kondo lattice model with alkaline-earth-metal atoms

    SciTech Connect (OSTI)

    Foss-Feig, Michael; Hermele, Michael; Rey, Ana Maria

    2010-05-15

    We study transport properties of alkaline-earth-metal 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, at low density, and in the heavy fermion phase is manifest in the dipole oscillations of the conduction band upon displacement of the trap center.

  16. Radioactive Elements in the Standard Atomic Weights Table.

    SciTech Connect (OSTI)

    Holden,N.E.

    2007-08-04

    In the 1949 Report of the Atomic Weights Commission, a series of new elements were added to the Atomic Weights Table. Since these elements had been produced in the laboratory and were not discovered in nature, the atomic weight value of these artificial products would depend upon the production method. Since atomic weight is a property of an element as it occurs in nature, it would be incorrect to assign an atomic weight value to that element. As a result of that discussion, the Commission decided to provide only the mass number of the most stable (or longest-lived) known isotope as the number to be associated with these entries in the Atomic Weights Table. As a function of time, the mass number associated with various elements has changed as longer-lived isotopes of a particular element has been found in nature, or as improved half-life values of an element's isotopes might cause a shift in the longest-lived isotope from one mass to another. In the 1957 Report of the Atomic Weights Commission, it was decided to discontinue the listing of the mass number in the Atomic Weights Table on the grounds that the kind of information supplied by the mass number is inconsistent with the primary purpose of the Table, i.e., to provide accurate values of 'these constants' for use in various chemical calculations. In addition to the Table of Atomic Weights, the Commission included an auxiliary Table of Radioactive Elements for the first time, where the entry would be the isotope of that element which was the most stable, i.e., the one with the longest known half-life. In their 1973 Report, the Commission noted that the users of the main Table of Atomic Weights were dissatisfied with the omission of values for some elements in that Table and it was decided to reintroduce the mass number for the radioactive elements into the main Table. In their 1983 Report, the Commission decided that radioactive elements were considered to lack a characteristic terrestrial isotopic composition

  17. Atoms.inp Archive: Crystallographic Data from GSECARS

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Newville, Matthew

    The Atoms.inp Archive is a collection of crystallographic data for use in XAFS analysis. The crystallographic data is stored as atoms.inp files, which contain all the information necessary to describe the crystal, and can be used by the program ATOMS to generate feff.inp files. These files can then be used by the FEFF program [See http://leonardo.phys.washington.edu/feff/] to calculate a theoretical XAFS spectrum for the crystal. This archive exists because it can take a considerable amount of time to locate a suitable reference for a model structure to use for making theoretical XAFS standards. Even then, references sometimes give non-standard or incomplete crystallographic notation that ATOMS has difficulty interpreting. All of this means that getting a reliable atoms.inp file can take quite a bit of effort. It is hoped that this collection of well-documented and well-tested atoms.inp files will eliminate much of the work in creating theoretical XAFS standards from FEFF. [Taken from http://cars9.uchicago.edu/~newville/adb/]. The collection currently has more than 200 crystal structures, 2748 data files, and it continues to expand. The collection is related to the UWXAFS Project [http://depts.washington.edu/uwxafs/] and to the work of the Consortium for Advanced Radiation Sources (CARS). After searching the Archive, a user may also choose to run the web version of ATOMS software.

  18. Proceedings of the workshop on opportunities for atomic physics using slow, highly-charged ions

    SciTech Connect (OSTI)

    Not Available

    1987-01-01

    The study of atomic physics with highly-charged ions is an area of intense activity at the present time because of a convergence of theoretical interest and advances in experimental techniques. The purpose of the Argonne ''Workshop on Opportunities for Atomic Physics Using Slow, Highly-Charged Ions'' was to bring together atomic, nuclear, and accelerator physicists in order to identify what new facilities would be most useful for the atomic physics community. The program included discussion of existing once-through machines, advanced ion sources, recoil ion techniques, ion traps, and cooler rings. One of the topics of the Workshop was to discuss possible improvement to the ANL Tandem-Linac facility (ATLAS) to enhance the capability for slowing down ions after they are stripped to a high-charge state (the Accel/Decel technique). Another topic was the opportunity for atomic physics provided by the ECR ion source which is being built for the Uranium Upgrade of ATLAS. 18 analytics were prepared for the individual papers in this volume.

  19. The Manhattan Project: Making of the Atomic Bomb | Department of Energy

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

    The Manhattan Project: Making of the Atomic Bomb The Manhattan Project: Making of the Atomic Bomb history of the manhattan project The Manhattan Project: Making of the Atomic Bomb (6.17 MB) More Documents & Publications Gosling, The Manhattan Project: Making the Atomic Bomb The_Manhattan_Project_2010.pdf The Manhattan Project: Making the Atomic Bomb

  20. Modeling and optimizing of the random atomic spin gyroscope drift based on the atomic spin gyroscope

    SciTech Connect (OSTI)

    Quan, Wei; Lv, Lin Liu, Baiqi

    2014-11-15

    In order to improve the atom spin gyroscope's operational accuracy and compensate the random error caused by the nonlinear and weak-stability characteristic of the random atomic spin gyroscope (ASG) drift, the hybrid random drift error model based on autoregressive (AR) and genetic programming (GP) + genetic algorithm (GA) technique is established. The time series of random ASG drift is taken as the study object. The time series of random ASG drift is acquired by analyzing and preprocessing the measured data of ASG. The linear section model is established based on AR technique. After that, the nonlinear section model is built based on GP technique and GA is used to optimize the coefficients of the mathematic expression acquired by GP in order to obtain a more accurate model. The simulation result indicates that this hybrid model can effectively reflect the characteristics of the ASG's random drift. The square error of the ASG's random drift is reduced by 92.40%. Comparing with the AR technique and the GP + GA technique, the random drift is reduced by 9.34% and 5.06%, respectively. The hybrid modeling method can effectively compensate the ASG's random drift and improve the stability of the system.

  1. Positron impact excitations of hydrogen atom embedded in weakly coupled plasmas: Formation of Rydberg atoms

    SciTech Connect (OSTI)

    Rej, Pramit; Ghoshal, Arijit

    2014-09-15

    Formation of Rydberg atoms due to 1s?nlm excitations of hydrogen, for arbitrary n, l, m, by positron impact in weakly coupled plasma has been investigated using a distorted-wave theory in the momentum space. The interactions among the charged particles in the plasma have been represented by Debye-Huckel potentials. Making use of a simple variationally determined wave function for the hydrogen atom, it has been possible to obtain the distorted-wave scattering amplitude in a closed analytical form. A detailed study has been made on the effects of plasma screening on the differential and total cross sections in the energy range 20300?eV of incident positron. For the unscreened case, our results agree nicely with some of the most accurate results available in the literature. To the best of our knowledge, such a study on the differential and total cross sections for 1s?nlm inelastic positron-hydrogen collisions for arbitrary n, l, m in weakly coupled plasmas is the first reported in the literature.

  2. 1979 bibliography of atomic and molecular processes. [Bibliography

    SciTech Connect (OSTI)

    1980-08-01

    This annotated bibliography lists 2146 works on atomic and molecular processes reported in publications dated 1979. Sources include scientific journals, conference proceedings, and books. Each entry is designated by one or more of the 114 categories of atomic and molecular processes used by the Controlled Fusion Atomic Data Center, Oak Ridge National Laboratory, to classify data. Also indicated is whether the work was experimental or theoretical, what energy range was covered, what reactants were investigated, and the country of origin of the first author. Following the bibliographical listing are indexes of reactants and authors.

  3. Frequency redistribution function for the polarized two-term atom

    SciTech Connect (OSTI)

    Casini, R.; Landi Degl'Innocenti, M.; Manso Sainz, R.; Landolfi, M.

    2014-08-20

    We present a generalized frequency redistribution function for the polarized two-term atom in an arbitrary magnetic field. This result is derived within a new formulation of the quantum problem of coherent scattering of polarized radiation by atoms in the collisionless regime. The general theory, which is based on a diagrammatic treatment of the atom-photon interaction, is still a work in progress. However, the results anticipated here are relevant enough for the study of the magnetism of the solar chromosphere and of interest for astrophysics in general.

  4. 1978 bibliography of atomic and molecular processes. [Bibliography

    SciTech Connect (OSTI)

    Not Available

    1980-03-01

    This annotated bibliography lists 2557 works on atomic and molecular processes reported in publications dated 1978. Sources include scientific journals, conference proceedings, and books. Each entry is designated by one or more of the 114 categories of atomic and molecular processes used by the Controlled Fusion Atomic Data Center to classify data. Also indicated is whether the work was experimental or theoretical, what energy range was covered, what reactants were investigated, and the country of origin of the first author. Following the bibliographical listing are indexes of reactants and authors.

  5. USE OF ATOMIC LAYER DEPOSITION OF FUNCTIONALIZATION OF NANOPOROUS BIOMATERIALS

    SciTech Connect (OSTI)

    Brigmon, R.; Narayan, R.; Adiga, S.; Pellin, M.; Curtiss, L.; Stafslien, S.; Chisholm, B.; Monteiro-Riviere, N.; Elam, J.

    2010-02-08

    Due to its chemical stability, uniform pore size, and high pore density, nanoporous alumina is being investigated for use in biosensing, drug delivery, hemodialysis, and other medical applications. In recent work, we have examined the use of atomic layer deposition for coating the surfaces of nanoporous alumina membranes. Zinc oxide coatings were deposited on nanoporous alumina membranes using atomic layer deposition. The zinc oxide-coated nanoporous alumina membranes demonstrated antimicrobial activity against Escherichia coli and Staphylococcus aureus bacteria. These results suggest that atomic layer deposition is an attractive technique for modifying the surfaces of nanoporous alumina membranes and other nanostructured biomaterials.

  6. America's Atomic Army: The Historical Archaeology of Camp Desert Rock

    SciTech Connect (OSTI)

    Susan R. Edwards

    2007-11-02

    Established in 1951, Camp Desert Rock served as the training ground for America's 'Atomic Army'. For the next six years, U.S. ground troops traveled to the Nevada desert to participate in military maneuvers during atmospheric atomic weapons testing. Nearly 60,000 soldiers received physical and psychological training in atomic warfare. Abandoned when atmospheric testing ended, Camp Desert Rock was dismantled and its buildings moved to other locations. Today, the camp appears as a sterile expanse of desert marked by rock-lined tent platforms, concrete foundations, and trash scatters. Although visually unimposing, the site is rich with the history of America's nuclear testing program.

  7. Atomic Structure of Au329(SR)84 Faradaurate Plasmonic Nanomolecules

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

    Kumara, Chanaka; Zuo, Xiaobing; Ilavsky, Jan; Cullen, David; Dass, Amala

    2015-04-03

    To design novel nanomaterials, it is important to precisely control the composition, determine the atomic structure, and manipulate the structure to tune the materials property. Here we present a comprehensive characterization of the material whose composition is Au329(SR)84 precisely, therefore referred to as a nanomolecule. The size homogeneity was shown by electron microscopy, solution X-ray scattering, and mass spectrometry. We proposed its atomic structure to contain the Au260 core using experiments and modeling of a total-scattering-based atomic-pair distribution functional analysis. HAADF-STEM images shows fcc-like 2.0 ± 0.1 nm diameter nanomolecules.

  8. Boron nitride nanosheets as oxygen-atom corrosion protective coatings

    SciTech Connect (OSTI)

    Yi, Min; Shen, Zhigang; Zhao, Xiaohu; Liang, Shuaishuai; Liu, Lei

    2014-04-07

    The research of two-dimensional nanomaterials for anticorrosion applications is just recently burgeoning. Herein, we demonstrate the boron nitride nanosheets (BNNSs) coatings for protecting polymer from oxygen-atom corrosion. High-quality BNNSs, which are produced by an effective fluid dynamics method with multiple exfoliation mechanisms, can be assembled into coatings with controlled thickness by vacuum filtration. After exposed in atom oxygen, the naked polymer is severely corroded with remarkable mass loss, while the BNNSs-coated polymer remains intact. Barrier and bonding effects of the BNNSs are responsible for the coating's protective performance. These preliminary yet reproducible results pave a way for resisting oxygen-atom corrosion.

  9. Resolved Atomic Interaction Sidebands in an Optical Clock Transition

    SciTech Connect (OSTI)

    Bishof, M.; Lin, Y.; Swallows, M. D.; Ye, J.; Rey, A. M.; Gorshkov, A. V.

    2011-06-24

    We report the observation of resolved atomic interaction sidebands (ISB) in the {sup 87}Sr optical clock transition when atoms at microkelvin temperatures are confined in a two-dimensional optical lattice. The ISB are a manifestation of the strong interactions that occur between atoms confined in a quasi-one-dimensional geometry and disappear when the confinement is relaxed along one dimension. The emergence of ISB is linked to the recently observed suppression of collisional frequency shifts. At the current temperatures, the ISB can be resolved but are broad. At lower temperatures, ISB are predicted to be substantially narrower and useful spectroscopic tools in strongly interacting alkaline-earth gases.

  10. Bulk and surface controlled diffusion of fission gas atoms

    SciTech Connect (OSTI)

    Andersson, Anders D.

    2012-08-09

    Fission gas retention and release impact nuclear fuel performance by, e.g., causing fuel swelling leading to mechanical interaction with the clad, increasing the plenum pressure and reducing the gap thermal conductivity. All of these processes are important to understand in order to optimize operating conditions of nuclear reactors and to simulate accident scenarios. Most fission gases have low solubility in the fuel matrix, which is especially pronounced for large fission gas atoms such as Xe and Kr, and as a result there is a significant driving force for segregation of gas atoms to extended defects such as grain boundaries or dislocations and subsequently for nucleation of gas bubbles at these sinks. Several empirical or semi-empirical models have been developed for fission gas release in nuclear fuels, e.g. [1-6]. One of the most commonly used models in fuel performance codes was published by Massih and Forsberg [3,4,6]. This model is similar to the early Booth model [1] in that it applies an equivalent sphere to separate bulk UO{sub 2} from grain boundaries represented by the sphere circumference. Compared to the Booth model, it also captures trapping at grain boundaries, fission gas resolution and it describes release from the boundary by applying timedependent boundary conditions to the circumference. In this work we focus on the step where fission gas atoms diffuse from the grain interior to the grain boundaries. The original Massih-Forsberg model describes this process by applying an effective diffusivity divided into three temperature regimes. In this report we present results from density functional theory calculations (DFT) that are relevant for the high (D{sub 3}) and intermediate (D{sub 2}) temperature diffusivities of fission gases. The results are validated by making a quantitative comparison to Turnbull's [8-10] and Matzke's data [12]. For the intrinsic or high temperature regime we report activation energies for both Xe and Kr diffusion in UO

  11. UNITED STATES ATOMIC ENERGY COMMISSION OAK RIDGE OPERATIONS

    Office of Legacy Management (LM)

    AL, 3 UNITED STATES ATOMIC ENERGY COMMISSION OAK RIDGE OPERATIONS CINCINNATI AREA P. 0. BOX 39198, CINCINNATI 39, OHIO IN REPLY REFER TO: 0:OJT --r.LAal Cl E:c Mr. J. H. Noyes, ...

  12. The LANL atomic kinetics modeling effort and its application...

    Office of Scientific and Technical Information (OSTI)

    effort and its application to W plasmas Citation Details In-Document Search Title: The LANL atomic kinetics modeling effort and its application to W plasmas This is the work of ...

  13. PPPL and General Atomics scientists make breakthrough in understanding...

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

    Plus One Share on Facebook Carlos Paz-Soldan, left, and Raffi Nazikian at the DIII-D tokamak. (Photo by Lisa PetrilloGeneral Atomics) Carlos Paz-Soldan, left, and Raffi Nazikian...

  14. Fe Atomic Data for Non-equilibrium Ionization Plasmas (Conference...

    Office of Scientific and Technical Information (OSTI)

    Resource Relation: Conference: AtomDB Work Week and Workshop ; 2012-08-06 - 2012-08-10 ; Cambridge, Massachusetts, United States Research Org: Los Alamos National Laboratory (LANL) ...

  15. UNITED, STATES ATOMIC ENERGY COMMlSSldN

    Office of Legacy Management (LM)

    UNITED, STATES ATOMIC ENERGY COMMlSSldN WASHINOTO. DC. 2oi45 August 28, 1973 llemorandum to Files TRANSFXR OF THE PALISZRTON URANIIDl Olig STtXXPPILg Introduct ion .Por background ...

  16. Researchers measure how specific atoms move in dielectric materials...

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

    how atoms move in dielectric materials in order to store that charge," says Tedi-Marie Usher, a Ph.D. candidate in materials science and engineering at NC State and lead...

  17. Distinguished Speaker Lecture Series: Plasma Physics at the Atomic...

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

    Optical-field multi-photon ionization, generated by high- power short-pulse lasers, is ... He is best known for introducing many of the concepts in strong field atomic and molecular ...

  18. Manhattan Project: Exploring the Atom, 1919-1932

    Office of Scientific and Technical Information (OSTI)

    The road to the atomic bomb began in earnest in 1919 with the first artificial transmutation of an element. The New Zealander Ernest Rutherford, working in the Cavendish Laboratory ...

  19. Workshop on Atomic Force Microscopy, Nanometrology and More ...

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

    Swarna Addepalli 2012.12.17 One of my colleagues from our global research center in India, K.G. V. Siva Kumar (Sivakumar), recently attended a workshop on Atomic Force...

  20. International Atomic Energy Agency (IAEA) | Open Energy Information

    Open Energy Info (EERE)

    Programs 4 References About "The IAEA is the worlds center of cooperation in the nuclear field. It was set up as the worlds "Atoms for Peace" organization in 1957 within...

  1. An Atomic-Level Understanding of Copper-Based Catalysts

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

    An Atomic-Level Understanding of Copper-Based Catalysts Print Copper-based catalysts are widely used in chemical industries to convert water and carbon monoxide to hydrogen, carbon ...

  2. Oxygen Control of Atomic Structure and Physical Properties of...

    Office of Scientific and Technical Information (OSTI)

    Properties of SrRuO3 Surfaces Citation Details In-Document Search Title: Oxygen Control of Atomic Structure and Physical Properties of SrRuO3 Surfaces Authors: Tselev, ...

  3. Manhattan Project: The Atomic Bombing of Nagasaki, August 9,...

    Office of Scientific and Technical Information (OSTI)

    ... For those areas of Nagasaki affected by the explosion, the death rate was comparable to ... The Army and the Atomic Bomb, United States Army in World War II (Washington: ...

  4. Clifford G. Shull, Neutron Diffraction, Hydrogen Atoms, and Neutron...

    Office of Scientific and Technical Information (OSTI)

    can then be obtained. Understanding where atoms are in a material and how they interact with one another is the key to understanding a material's properties. "Then we can...

  5. Adsorption configurations of two nitrogen atoms on graphene

    SciTech Connect (OSTI)

    Rani, Babita, E-mail: babitabaghla15@gmail.com [Department of Physics, Punjabi University, Patiala- 147 002 and Department of Physics, Panjab University, Chandigarh- 160 014 (India); Jindal, V. K.; Dharamvir, Keya [Department of Physics, Panjab University, Chandigarh- 160 014 (India)

    2014-04-24

    We present calculations for different possible configurations of two nitrogen adatoms on graphene using the code VASP, based on Density Functional Theory (DFT). Two N atoms adsorbed on the graphene sheet can share a bond in two ways. They take positions either just above two adjacent carbon atoms or they form a bridge across opposite bonds of a hexagon in the graphene sheet. Both these configurations result into structural distortion of the sheet. Another stable configuration involving two N atoms consists of an N{sub 2} molecule which is physisorbed at a distance 3.69 on the graphene sheet. Two N atoms can also be adsorbed on alternate bridge sites of neighbouring hexagons of graphene. This configuration again leads to distortion of the sheet in perpendicular direction.

  6. Atomic-scale imaging correlation on the deformation and sensing...

    Office of Scientific and Technical Information (OSTI)

    Title: Atomic-scale imaging correlation on the deformation and sensing mechanisms of SnO2 nanowires Authors: Sun, Yong 1 ; Liu, Jie 2 ; Blom, Douglas 3 ; Koley, Goutam 2 ; ...

  7. I UNITED STATES I ATOMIC ENERGY C O M M

    Office of Legacy Management (LM)

    .a, I UNITED STATES I ATOMIC ENERGY C O M M ISSlOfr '. Dlstributicm: liance,vcy 6-9-61 ltr L ,. : ..a 3: ,:< i, ' i . . il.,, ,: . : ,",' i ....

  8. Part 810-ASSISTANCE TO FOREIGN ATOMIC ENERGY ACTIVITIES Sec.

    National Nuclear Security Administration (NNSA)

    Atomic Energy Act of 1954, as amended by the Nuclear Non-Proliferation Act of 1978, Pub. ... NNPA means the Nuclear Non-Proliferation Act of 1978. NPT means the Treaty on the ...

  9. "Stationary Flowing Liquid Lithium System For Pumping Out Atomic...

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

    Lithium System For Pumping Out Atomic Hydrogen Isotopes and Ions" Leonid E. Zakharov and Charles Gentile The system is comprised of a stationary closed loop for liquid lithium flow ...

  10. UNITED STATES ATOMIC ENERGY COMMISSION SPECIAL NUCLEAR MATERIAL...

    Office of Legacy Management (LM)

    STATES ATOMIC ENERGY COMMISSION SPECIAL NUCLEAR MATERIAL LlCENSE pp.o-o 43 Licensee 1. ... Date Sepikmber 30, I.962 -6. Special Nuclear:Material SnrichedtoS I under this ...

  11. Tomographic study of atomic-scale redistribution of platinum...

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

    Tomographic study of atomic-scale redistribution of platinum during the silicidation of Ni0.95Pt0.05Si(100) thin films Home Author: P. Adusumilli, L. J. Lauhon, D. N. Seidman, C....

  12. Investigation of odd-order nonlinear susceptibilities in atomic vapors

    SciTech Connect (OSTI)

    Yan, Yaqi; Shaanxi Key Laboratory of Information Photonic Technique, Xi’an Jiaotong University, Xi’an 710049; Teaching and Research Section of Maths and Physics, Guangzhou Commanding Academy of Chinese People’s Armed Police Force, Guangzhou, 510440 ; Wu, Zhenkun; Si, Jinhai; Yan, Lihe; Zhang, Yiqi; Yuan, Chenzhi; Sun, Jia; Shaanxi Key Laboratory of Information Photonic Technique, Xi’an Jiaotong University, Xi’an 710049 ; Zhang, Yanpeng; Shaanxi Key Laboratory of Information Photonic Technique, Xi’an Jiaotong University, Xi’an 710049

    2013-06-15

    We theoretically deduce the macroscopic symmetry constraints for arbitrary odd-order nonlinear susceptibilities in homogeneous media including atomic vapors for the first time. After theoretically calculating the expressions using a semiclassical method, we demonstrate that the expressions for third- and fifth-order nonlinear susceptibilities for undressed and dressed four- and six-wave mixing (FWM and SWM) in atomic vapors satisfy the macroscopic symmetry constraints. We experimentally demonstrate consistence between the macroscopic symmetry constraints and the semiclassical expressions for atomic vapors by observing polarization control of FWM and SWM processes. The experimental results are in reasonable agreement with our theoretical calculations. -- Highlights: •The macroscopic symmetry constraints are deduced for homogeneous media including atomic vapors. •We demonstrate that odd-order nonlinear susceptibilities satisfy the constraints. •We experimentally demonstrate the deduction in part.

  13. An Atomic-Level Understanding of Copper-Based Catalysts

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

    ... The surface becomes completely unstable at the atomic level, causing it to readily ... in the presence of CO. Ambient-pressure x-ray photoelectron spectroscopy (AP-XPS) at ...

  14. Measurement of Transient Atomic-scale Displacements in Thin Films...

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

    Measurement of Transient Atomic-scale Displacements in Thin Films with Picosecond and ... The inset shows a streak camera measurement of the x-ray pulse duration. Ultrafast x-ray ...

  15. Atomic, molecular, and nuclear quantum dynamics and control in...

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

    Atomic, molecular, and nuclear quantum dynamics and control in (strong) visible to x-ray (laser) fields Wednesday, July 20, 2016 - 3:00pm SLAC, Redtail Hawk Conference Room 108A ...

  16. Vanadium dioxide film protected with an atomic-layer-deposited...

    Office of Scientific and Technical Information (OSTI)

    In this work, the authors deposited an ultrathin Alsub 2Osub 3 film with atomic layer ... heated at 350 C. However, in a humid environment at prolonged durations, a thicker ALD ...

  17. Imaging Lithium Atoms at Sub-Angstrom Resolution (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Imaging Lithium Atoms at Sub-Angstrom Resolution Citation Details In-Document Search Title: ... Publication Date: 2005-01-03 OSTI Identifier: 875740 Report Number(s): ...

  18. General Atomics (GA) Fusion News: A New Spin on Understanding Plasma

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

    Confinement | Princeton Plasma Physics Lab General Atomics (GA) Fusion News: A New Spin on Understanding Plasma Confinement American Fusion News Category: General Atomics (GA) Link: General Atomics (GA) Fusion News: A New Spin on Understanding Plasma Confinement

  19. Albert Einstein Alerts President Roosevelt of German Atomic Energy Program

    National Nuclear Security Administration (NNSA)

    | National Nuclear Security Administration | (NNSA) Albert Einstein Alerts President Roosevelt of German Atomic Energy Program Albert Einstein Alerts President Roosevelt of German Atomic Energy Program Washington, DC Albert Einstein writes President Franklin D. Roosevelt, alerting the President to the importance of research on nuclear chain reactions and the possibility that research might lead to developing powerful bombs. Einstein notes that Germany has stopped the sale of uranium and

  20. The Harnessed Atom - Student Edition | Department of Energy

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

    Student Edition The Harnessed Atom - Student Edition The Harnessed Atom is a middle school science, technology, engineering, and math (STEM) curriculum extension that focuses on nuclear science and energy. It is designed to provide students with accurate, unbiased, and up-to-date information on the roles that energy and nuclear science play in our lives. The curriculum includes essential principles and fundamental concepts of energy science. This update is based on the original 1985 Harnessed

  1. The Harnessed Atom - Teachers' Edition | Department of Energy

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

    Teachers' Edition The Harnessed Atom - Teachers' Edition The Harnessed Atom is a middle school science, technology, engineering, and math (STEM) curriculum extension that focuses on nuclear science and energy. It is designed to provide students with accurate, unbiased, and up-to-date information on the roles that energy and nuclear science play in our lives. The curriculum includes essential principles and fundamental concepts of energy science. This update is based on the original 1985

  2. Klotz visits Bettis Atomic Power Laboratory | National Nuclear Security

    National Nuclear Security Administration (NNSA)

    Administration | (NNSA) Klotz visits Bettis Atomic Power Laboratory Wednesday, July 8, 2015 - 1:03pm Lt. Gen. Frank G. Klotz, DOE Undersecretary for Nuclear Security and NNSA Administrator, visited the Bettis Atomic Power Laboratory in West Mifflin, PA on July 2, 2015. NNSA Blog Gen. Klotz toured through several test facilities where Bettis personnel reviewed ongoing development efforts to qualify techniques for in-situ repairs of nuclear powered submarine components, discussed full scale

  3. NNSA Awards Mo-99 Cooperative Agreement to General Atomics | National

    National Nuclear Security Administration (NNSA)

    Nuclear Security Administration | (NNSA) Awards Mo-99 Cooperative Agreement to General Atomics September 30, 2015 WASHINGTON, DC - Today, the Department of Energy's National Nuclear Security Administration (DOE/NNSA) announced that it will award a cooperative agreement to General Atomics (GA) to support its project for domestic production of molybdenum-99 (Mo-99) without highly enriched uranium (HEU). Mo-99 is the parent isotope of technetium-99m, which is the most widely used radioisotope

  4. An Atomic-Level Understanding of Copper-Based Catalysts

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

    An Atomic-Level Understanding of Copper-Based Catalysts Print Copper-based catalysts are widely used in chemical industries to convert water and carbon monoxide to hydrogen, carbon dioxide, and methanol. There are theoretical models used to explain this reaction, but a complete understanding of the process has been lacking. However, recent research at the ALS has shed light on the process, giving scientists key data about how copper-based catalysts function at the atomic level. These catalysts

  5. Former Oak Ridge Bechtel Jacobs Employee Charged with Violating Atomic

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

    Energy Act | Department of Energy Former Oak Ridge Bechtel Jacobs Employee Charged with Violating Atomic Energy Act Former Oak Ridge Bechtel Jacobs Employee Charged with Violating Atomic Energy Act Department of Justice press release announcing that a federal grand jury in the Eastern District of Tennessee has charged a former contract worker, Roy Lynn Oakley, at East Tennessee Technology Park with converting to his own use restricted government materials utilized for uranium enrichment and

  6. Nature-inspired nanostructures yield first atomic resolution of peptide

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

    nanosheet Nature-inspired nanostructures yield first atomic resolution of peptide nanosheet Click to share on Facebook (Opens in new window) Click to share on Twitter (Opens in new window) Click to share on Reddit (Opens in new window) Click to share on Pinterest (Opens in new window) This atomic-resolution simulation of a two-dimensional peptoid nanosheet reveals a snake-like structure never seen before. This research could help scentists design incredibly sensitive chemical detectors or

  7. Lensless Imaging of Atomic Surface Structures via Ptychography | Stanford

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

    Synchrotron Radiation Lightsource Lensless Imaging of Atomic Surface Structures via Ptychography Monday, August 12, 2013 - 11:00am SLAC, Conference Room 137-322 Presented by Chenhui Zhu Materials Science Division, Argonne National Laboratory, Argonne, IL Coherent x-ray diffraction imaging (CDI) is a lensless technique, which has been in rapid progress recently due to its great potential for high spatial resolution and in-situ measurement. We demonstrate by numerical simulation that atomic

  8. LSU EFRC - Center for Atomic Level Catalyst Design - About Us

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

    About Us >> space control Our Mission Statement space control Message From The Director space control space control Our Mission Statement space control "Building Effective Catalysts from First Principles: Computational Catalysis and Atomic-Level Synthesis" The mission of LSU's Center for Atomic Level Catalyst Design is to advance: the ability of computational methods to accurately model catalytic reactions on solid surfaces over time and length scales far more representative of

  9. LSU EFRC - Center for Atomic Level Catalyst Design - Technical Conference

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

    2010 Technical Conference 2010 >> space control 2010 Technical Conference: Center for Atomic-level Catalyst Design Nov. 1-3, 2010 space control 2010 Technical Conference: Poster Presentations space control space control Technical Conference 2010 space control 2010 Technical Conference: Center for Atomic-level Catalyst Design Nov. 1-3, 2010 photos-1.jpg photos-10.jpg photos-11.jpg photos-13.jpg photos-14.jpg photos-15.jpg Louisiana State University, Lod Cook Alumni Center, Baton Rouge,

  10. LSU EFRC - Center for Atomic Level Catalyst Design - Technical Conference

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

    2011 1 space control 2011 Technical Conference: Center for Atomic-level Catalyst Design Oct. 25-27, 2011 Note: Links available only on request to CALCD members. Contact Webmaster Presentations from the EFRC Technical Conference 2011 Mike Janik Mike Janik (Penn State): "Modeling and synthesis of rare earth oxides" Ulrike Diebold Ulrike Diebold (TU Vienna): "Designing Nanocatalysts via Atomically Controlled Metal Clusters and their Supports" Petra de Jongh Petra de Jongh

  11. International Atomic Energy Agency holds conference on fusion roadmap |

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

    Princeton Plasma Physics Lab International Atomic Energy Agency holds conference on fusion roadmap By John Greenwald November 8, 2012 Tweet Widget Google Plus One Share on Facebook Hutch Neilson, third from left, chaired the four-day International Atomic Energy Agency Conference at the University of California at Los Angeles in mid-October, which drew 70 participants from 16 countries and international groups. Pictured here from left to right are Keeman Kim, National Fusion Research

  12. Katharine Page: Atomic-level insights for better materials

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

    Katharine Page: Atomic-level insights for better materials Alumni Link: Opportunities, News and Resources for Former Employees Latest Issue:September 2015 all issues All Issues » submit Katharine Page: Atomic-level insights for better materials Page's research supports materials' advances that could have wide-ranging impact, investigating, manipulating and manufacturing nano-particles. May 1, 2014 Katherine Page Katherine Page Contact Linda Anderman Email A Love for Science Impassioned by

  13. DOE - Office of Legacy Management -- Bettis Atomic Power Laboratories - PA

    Office of Legacy Management (LM)

    44 Bettis Atomic Power Laboratories - PA 44 FUSRAP Considered Sites Site: Bettis Atomic Power Laboratories (PA.44 ) Eliminated from further consideration under FUSRAP Designated Name: Not Designated Alternate Name: None Location: Allegheny County , West Mifflin , Pennsylvania PA.44-1 Evaluation Year: Circa 1987 PA.44-2 Site Operations: Conducted activities directed toward the design, development, testing, and operational follow of nuclear reactor propulsion plants for Naval surface and

  14. An Atomic-Level Understanding of Copper-Based Catalysts

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

    An Atomic-Level Understanding of Copper-Based Catalysts Print Copper-based catalysts are widely used in chemical industries to convert water and carbon monoxide to hydrogen, carbon dioxide, and methanol. There are theoretical models used to explain this reaction, but a complete understanding of the process has been lacking. However, recent research at the ALS has shed light on the process, giving scientists key data about how copper-based catalysts function at the atomic level. These catalysts

  15. Atom-probe tomography of tribological boundary films resulting from

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

    boron-based oil additives | Argonne National Laboratory Atom-probe tomography of tribological boundary films resulting from boron-based oil additives Title Atom-probe tomography of tribological boundary films resulting from boron-based oil additives Publication Type Journal Article Year of Publication 2016 Authors Kim, Y-J, Baik, S-I, Bertolucci-Coelho, L, Mazzaferro, L, Ramirez, G, Erdemir, A, Seidman, DN Journal Scripta Materialia Volume 111 Start Page 65 Issue 15 Pagination 4 Date

  16. Atomically Precise Electrocatalyst for Oxygen Evolution Reaction | Stanford

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

    Synchrotron Radiation Lightsource Atomically Precise Electrocatalyst for Oxygen Evolution Reaction Thursday, March 31, 2016 Traditional heterogeneous catalysts contain a range of particles sizes, crystallographic faces, and surface structures. This heterogeneity makes catalysts design a challenge because the active sites responsible for catalytic activity are simply not known. An emerging class of "atomically-precise" nanocatalysts can help alleviate this problem because they form

  17. Missing Oxygen Atoms Are Key to Robust Spintronic Material

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

    Missing Oxygen Atoms Are Key to Robust Spintronic Material Missing Oxygen Atoms Are Key to Robust Spintronic Material Print Friday, 01 April 2016 11:44 The endless pursuit of faster, more energy-efficient computers has led to the emergence of the field of spintronics, where the manipulation and detection of electron spins are utilized in electronic circuits. A particular class of materials called dilute magnetic oxides are promising candidates for spintronics applications because they exhibit

  18. Fe Atomic Data for Non-equilibrium Ionization Plasmas (Conference) |

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Fe Atomic Data for Non-equilibrium Ionization Plasmas Citation Details In-Document Search Title: Fe Atomic Data for Non-equilibrium Ionization Plasmas No abstract prepared. Authors: Eriksen, Kristoffer A. [1] ; Fontes, Christopher J. [1] ; Colgan, James P. [1] ; Zhang, Honglin [1] ; Hungerford, Aimee L. [1] ; Fryer, Christopher L. [1] ; Hughes, John P. [2] ; Smith, Randall K. [3] ; Badenes, Carles [4] + Show Author Affiliations Los Alamos National Laboratory Rutgers

  19. Cooling by Time Reversal of Atomic Matter Waves

    SciTech Connect (OSTI)

    Martin, J.; Georgeot, B.; Shepelyansky, D. L. [Laboratoire de Physique Theorique, Universite de Toulouse III, CNRS, 31062 Toulouse (France)

    2008-02-01

    We propose an experimental scheme which allows us to realized approximate time reversal of matter waves for ultracold atoms in the regime of quantum chaos. We show that a significant fraction of the atoms return back to their original state, being at the same time cooled down by several orders of magnitude. We give a theoretical description of this effect supported by extensive numerical simulations. The proposed scheme can be implemented with existing experimental setups.

  20. DOE - Office of Legacy Management -- Shippingport Atomic Power Plant - PA

    Office of Legacy Management (LM)

    13 Shippingport Atomic Power Plant - PA 13 FUSRAP Considered Sites Site: SHIPPINGPORT ATOMIC POWER PLANT (PA.13 ) Eliminated from further consideration under FUSRAP. Designated Name: Not Designated Alternate Name: Duquesne Light Company PA.13-1 Location: 25 miles west of Pittsburgh in Beaver County , Shippingport , Pennsylvania PA.13-2 Evaluation Year: circa 1987 PA.13-3 Site Operations: First commercially operated nuclear power reactor. Joint project (Federal Government an Duquesne Light

  1. Atomic, molecular, and nuclear quantum dynamics and control in (strong)

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

    visible to x-ray (laser) fields | Stanford Synchrotron Radiation Lightsource Atomic, molecular, and nuclear quantum dynamics and control in (strong) visible to x-ray (laser) fields Wednesday, July 20, 2016 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: Thomas Pfeifer, MPIK Heidelberg Program Description Electrons bound in atoms and small molecules represent some of the most fundamental quantum systems. These systems are so well known and reliable that they serve as optical

  2. Detection of J-coupling using atomic magnetometer

    DOE Patents [OSTI]

    Ledbetter, Micah P.; Crawford, Charles W.; Wemmer, David E.; Pines, Alexander; Knappe, Svenja; Kitching, John; Budker, Dmitry

    2015-09-22

    An embodiment of a method of detecting a J-coupling includes providing a polarized analyte adjacent to a vapor cell of an atomic magnetometer; and measuring one or more J-coupling parameters using the atomic magnetometer. According to an embodiment, measuring the one or more J-coupling parameters includes detecting a magnetic field created by the polarized analyte as the magnetic field evolves under a J-coupling interaction.

  3. Single-atom and two-atom Ramsey interferometry with quantized fields

    SciTech Connect (OSTI)

    Agarwal, G.S.; Pathak, P.K. [Physical Research Laboratory, Navrangpura, Ahmedabad 380 009 (India); Scully, M.O. [Department of Physics, Texas A and M University, College Station, Texas 77843 (United States); Max-Planck Institut fuer Quantenoptik, Garching (Germany)

    2003-04-01

    Implications of field quantization on Ramsey interferometry are discussed and general conditions for the occurrence of interference are obtained. Interferences do not occur if the fields in two Ramsey zones have a precise number of photons. However, in this case we show how an analog of Hanbury-Brown Twiss photon-photon correlation interferometry can be used to discern a variety of interference effects as the two independent Ramsey zones get entangled by the passage of the first atom. Interferences are restored by working with fields at a single-photon level. Generation of entangled states including states such as vertical bar 2,0>+e{sup i{theta}} vertical bar 0,2> is discussed.

  4. Effects of hydrogen atoms on surface conductivity of diamond film

    SciTech Connect (OSTI)

    Liu, Fengbin Cui, Yan; Qu, Min; Di, Jiejian

    2015-04-15

    To investigate the effects of surface chemisorbed hydrogen atoms and hydrogen atoms in the subsurface region of diamond on surface conductivity, models of hydrogen atoms chemisorbed on diamond with (100) orientation and various concentrations of hydrogen atoms in the subsurface layer of the diamond were built. By using the first-principles method based on density functional theory, the equilibrium geometries and densities of states of the models were studied. The results showed that the surface chemisorbed hydrogen alone could not induce high surface conductivity. In addition, isolated hydrogen atoms in the subsurface layer of the diamond prefer to exist at the bond centre site of the C-C bond. However, such a structure would induce deep localized states, which could not improve the surface conductivity. When the hydrogen concentration increases, the C-H-C-H structure and C-3H{sub bc}-C structure in the subsurface region are more stable than other configurations. The former is not beneficial to the increase of the surface conductivity. However, the latter would induce strong surface states near the Fermi level, which would give rise to high surface conductivity. Thus, a high concentration of subsurface hydrogen atoms in diamond would make significant contributions to surface conductivity.

  5. Creation and recovery of a W(111) single atom gas field ion source

    SciTech Connect (OSTI)

    Pitters, Jason L.; Urban, Radovan; Wolkow, Robert A.

    2012-04-21

    Tungsten single atom tips have been prepared from a single crystal W(111) oriented wire using the chemical assisted field evaporation and etching method. Etching to a single atom tip occurs through a symmetric structure and leads to a predictable last atom unlike etching with polycrystalline tips. The single atom tip formation procedure is shown in an atom by atom removal process. Rebuilds of single atom tips occur on the same crystalline axis as the original tip such that ion emission emanates along a fixed direction for all tip rebuilds. This preparation method could be utilized and developed to prepare single atom tips for ion source development.

  6. Deposition of cobalt atoms onto Alq 3 films: A molecular dynamics...

    Office of Scientific and Technical Information (OSTI)

    Deposition of cobalt atoms onto Alq 3 films: A molecular dynamics study Prev Next Title: Deposition of cobalt atoms onto Alq 3 films: A molecular dynamics study Authors: ...

  7. RADIOACTIVE ELEMENTS IN THE STANDARD ATOMIC WEIGHTS TABLE

    SciTech Connect (OSTI)

    Holden, N.E.; Holden, N.; Holden,N.E.

    2011-07-27

    In the 1949 Report of the Atomic Weights Commission, a series of new elements were added to the Atomic Weights Table. Since these elements had been produced in the laboratory and were not discovered in nature, the atomic weight value of these artificial products would depend upon the production method. Since atomic weight is a property of an element as it occurs in nature, it would be incorrect to assign an atomic weight value to that element. As a result of that discussion, the Commission decided to provide only the mass number of the most stable (or longest-lived) known isotope as the number to be associated with these entries in the Atomic Weights Table. As a function of time, the mass number associated with various elements has changed as longer-lived isotopes of a particular element has been found in nature, or as improved half-life values of an element's isotopes might cause a shift in the longest-lived isotope from one mass to another. In the 1957 Report of the Atomic Weights Commission, it was decided to discontinue the listing of the mass number in the Atomic Weights Table on the grounds that the kind of information supplied by the mass number is inconsistent with the primary purpose of the Table, i.e., to provide accurate values of 'these constants' for use in various chemical calculations. In addition to the Table of Atomic Weights, the Commission included an auxiliary Table of Radioactive Elements for the first time, where the entry would be the isotope of that element which was the most stable, i.e., the one with the longest known half-life. In their 1973 Report, the Commission noted that the users of the main Table of Atomic Weights were dissatisfied with the omission of values for some elements in that Table and it was decided to reintroduce the mass number for the radioactive elements into the main Table. In their 1983 Report, the Commission decided that radioactive elements were considered to lack a characteristic terrestrial isotopic composition

  8. Steven Chu: Laser Cooling and Trapping of Atoms

    Office of Scientific and Technical Information (OSTI)

    ... Interview with Steven Chu; August 26, 2008; Nobelprize.org Interview: Steven Chu, American Scientist, January - February 1998 Energy Nominee Steven Chu on Climate Change, National ...

  9. Steven Chu: Laser Cooling and Trapping of Atoms

    Office of Scientific and Technical Information (OSTI)

    in the Physics Department at the University of California, Berkeley, and 'the Theodore and Frances Geballe Professor of Physics and Applied Physics at Stanford University. ...

  10. Generic equilibration dynamics of planar defects in trapped atomic...

    Office of Scientific and Technical Information (OSTI)

    Publication Date: 2015-03-18 OSTI Identifier: 1179955 Type: Publisher's Accepted Manuscript Journal Name: Physical Review A Additional Journal Information: Journal Volume: 91; ...

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

    Office of Environmental Management (EM)

    Department of Energy (AHAM) Ex parte Memo Association of Home Appliance Manufacturers (AHAM) Ex parte Memo This memo memorializes the meeting between AHAM and the Department of Energy on October 17, 2012, for inclusion in the public docket. Memo_exparte_October 17 2012_BCS.pdf (103.36 KB) More Documents & Publications Ex parte Communication Memo AHAM Ex Parte Memorandum Ex Parte Meeting with DOE and Navigant Consulting on Battery Charger Energy

    RFI_July 2015_FINAL (00039560) (54.18

  12. PCTFE as a solution to birefringence in atom trap viewports

    SciTech Connect (OSTI)

    Warner, C. L.; Behr, J. A.; Gorelov, A.

    2014-11-15

    We have developed and characterized optical viewports with the glass-to-metal seal made by the plastic PCTFE (polychlorotrifluoroethylene). The goal is to reduce stress-induced birefringence while maintaining ultra-high vacuum compatibility. We have maintained a Stokes parameter S{sub 3} of 0.9986, and achieved <5 × 10{sup −11} Torr partial pressure of air. We have also measured the diffusion and permeation of helium through PCTFE and placed upper limits on nitrogen, oxygen, and argon permeation, as PCTFE has been suggested as an o-ring for transport of environmental noble gas samples, though we know of no other noble gas measurements.

  13. Quantum-noise-limited interferometric measurement of atomic noise: Towards spin squeezing on the Cs clock transition

    SciTech Connect (OSTI)

    Oblak, Daniel; Tittel, Wolfgang; Vershovski, Anton K.; Mikkelsen, Jens K.; Soerensen, Jens L.; Petrov, Plamen G.; Garrido Alzar, Carlos L.; Polzik, Eugene S.

    2005-04-01

    We investigate theoretically and experimentally a nondestructive interferometric measurement of the state population of an ensemble of laser-cooled and trapped atoms. This study is a step toward generation of (pseudo)spin squeezing of cold atoms targeted at the improvement of the cesium clock performance beyond the limit set by the quantum projection noise of atoms. We calculate the phase shift and the quantum noise of a near-resonant optical probe pulse propagating through a cloud of cold {sup 133}Cs atoms. We analyze the figure of merit for a quantum nondemolition (QND) measurement of the collective pseudospin and show that it can be expressed simply as a product of the ensemble optical density and the pulse-integrated rate of the spontaneous emission caused by the off-resonant probe light. Based on this, we propose a protocol for the sequence of operations required to generate and utilize spin squeezing for the improved atomic clock performance via a QND measurement on the probe light. In the experimental part we demonstrate that the interferometric measurement of the atomic population can reach a sensitivity of the order of {radical}(N{sub at}) in a cloud of N{sub at} cold atoms, which is an important benchmark toward the experimental realization of the theoretically analyzed protocol.

  14. Hydrogen Atom Reactivity toward Aqueous tert-Butyl Alcohol

    SciTech Connect (OSTI)

    Lymar S. V.; Schwarz, H.A.

    2012-02-09

    Through a combination of pulse radiolysis, purification, and analysis techniques, the rate constant for the H + (CH{sub 3}){sub 3}COH {yields} H{sub 2} + {sm_bullet}CH{sub 2}C(CH{sub 3}){sub 2}OH reaction in aqueous solution is definitively determined to be (1.0 {+-} 0.15) x 10{sup 5} M{sup -1} s{sup -1}, which is about half of the tabulated number and 10 times lower than the more recently suggested revision. Our value fits on the Polanyi-type, rate-enthalpy linear correlation ln(k/n) = (0.80 {+-} 0.05){Delta}H + (3.2 {+-} 0.8) that is found for the analogous reactions of other aqueous aliphatic alcohols with n equivalent abstractable H atoms. The existence of such a correlation and its large slope are interpreted as an indication of the mechanistic similarity of the H atom abstraction from {alpha}- and {beta}-carbon atoms in alcohols occurring through the late, product-like transition state. tert-Butyl alcohol is commonly contaminated by much more reactive secondary and primary alcohols (2-propanol, 2-butanol, ethanol, and methanol), whose content can be sufficient for nearly quantitative scavenging of the H atoms, skewing the H atom reactivity pattern, and explaining the disparity of the literature data on the H + (CH{sub 3}){sub 3}COH rate constant. The ubiquitous use of tert-butyl alcohol in pulse radiolysis for investigating H atom reactivity and the results of this work suggest that many other previously reported rate constants for the H atom, particularly the smaller ones, may be in jeopardy.

  15. HRTEM Imaging of Atoms at Sub-Angstrom Resolution

    SciTech Connect (OSTI)

    O'Keefe, Michael A.; Allard, Lawrence F.; Blom, Douglas A.

    2005-04-06

    John Cowley and his group at Arizona State University pioneered the use of transmission electron microscopy (TEM) for high-resolution imaging. Images were achieved three decades ago showing the crystal unit cell content at better than 4 Angstrom resolution. This achievement enabled researchers to pinpoint the positions of heavy atom columns within the unit cell. Lighter atoms appear as resolution is improved to sub-Angstrom levels. Currently, advanced microscopes can image the columns of the light atoms (carbon, oxygen, nitrogen) that are present in many complex structures, and even the lithium atoms present in some battery materials. Sub-Angstrom imaging, initially achieved by focal-series reconstruction of the specimen exit surface wave, will become common place for next-generation electron microscopes with CS-corrected lenses and monochromated electron beams. Resolution can be quantified in terms of peak separation and inter-peak minimum, but the limits imposed on the attainable resolution by the properties of the micro-scope specimen need to be considered. At extreme resolution the ''size'' of atoms can mean that they will not be resolved even when spaced farther apart than the resolution of the microscope.

  16. Reactions of carbon atoms in pulsed molecular beams

    SciTech Connect (OSTI)

    Reisler, H.

    1993-12-01

    This research program consists of a broad scope of experiments designed to unravel the chemistry of atomic carbon in its two spin states, P and D, by using well-controlled initial conditions and state-resolved detection of products. Prerequisite to the proposed studies (and the reason why so little is known about carbon atom reactions), is the development of clean sources of carbon atoms. Therefore, in parallel with the studies of its chemistry and reaction dynamics, the authors continuously explore new, state-specific and efficient ways of producing atomic carbon. In the current program, C({sup 3}P) is produced via laser ablation of graphite, and three areas of study are being pursued: (i) exothermic reactions with small inorganic molecules (e.g., O{sub 2}, N{sub 2}O, NO{sub 2}) that can proceed via multiple pathways; (ii) the influence of vibrational and translational energy on endothermic reactions involving H-containing reactants that yield CH products (e.g., H{sub 2}O H{sub 2}CO); (iii) reactions of C({sup 3}P) with free radicals (e.g., HCO, CH{sub 3}O). In addition, the authors plan to develop a source of C({sup 1}D) atoms by exploiting the pyrolysis of diazotetrazole and its salts in the ablation source. Another important goal involves collaboration with theoreticians in order to obtain relevant potential energy surfaces, rationalize the experimental results and predict the roles of translational and vibrational energies.

  17. Molecular Dynamics and Energy Minimization Based on Embedded Atom Method

    Energy Science and Technology Software Center (OSTI)

    1995-03-01

    This program performs atomic scale computer simulations of the structure and dynamics of metallic system using energetices based on the Embedded Atom Method. The program performs two types of calculations. First, it performs local energy minimization of all atomic positions to determine ground state and saddle point energies and structures. Second, it performs molecular dynamics simulations to determine thermodynamics or miscroscopic dynamics of the system. In both cases, various constraints can be applied to themore » system. The volume of the system can be varied automatically to achieve any desired external pressure. The temperature in molecular dynamics simulations can be controlled by a variety of methods. Further, the temperature control can be applied either to the entire system or just a subset of the atoms that would act as a thermal source/sink. The motion of one or more of the atoms can be constrained to either simulate the effects of bulk boundary conditions or to facilitate the determination of saddle point configurations. The simulations are performed with periodic boundary conditions.« less

  18. Barrier-free subsurface incorporation of 3d metal atoms into Bi(111) films

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

    Klein, C.; Vollmers, N. J.; Gerstmann, U.; Zahl, P.; Lukermann, D.; Jnawali, G.; Pfnur, H.; Sutter, P.; Tegenkamp, C.; Schmidt, W. G.; et al

    2015-05-27

    By combining scanning tunneling microscopy with density functional theory it is shown that the Bi(111) surface provides a well-defined incorporation site in the first bilayer that traps highly coordinating atoms such as transition metals (TMs) or noble metals. All deposited atoms assume exactly the same specific sevenfold coordinated subsurface interstitial site while the surface topography remains nearly unchanged. Notably, 3d TMs show a barrier-free incorporation. The observed surface modification by barrier-free subsorption helps to suppress aggregation in clusters. Thus, it allows a tuning of the electronic properties not only for the pure Bi(111) surface, but may also be observed formore » topological insulators formed by substrate-stabilized Bi bilayers.« less

  19. The Atomic Vapor Laser Isotope Separation Program. [Atomic Vapor Laser Isotope Separation (AVLIS) Program

    SciTech Connect (OSTI)

    Not Available

    1992-11-09

    This report provides the finding and recommendations on the audit of the Atomic Vapor Laser Isotope Separation (AVLIS) program. The status of the program was assessed to determine whether the Department was achieving objectives stated in its January 1990 Plan for the Demonstration, Transition and Deployment of AVLIS Technology. Through Fiscal Year 1991, the Department had spent about $1.1 billion to develop AVLIS technology. The January 1990 plan provided for AVLIS to be far enough along by September to enable the Department to make a determination of the technical and economic feasibility of deployment. However, the milestones needed to support that determination were not met. An estimated $550 million would be needed to complete AVLIS engineering development and related testing prior to deployment. The earliest possible deployment date has slipped to beyond the year 2000. It is recommended that the Department reassess the requirement for AVLIS in light of program delays and changes that have taken place in the enrichment market since January 1990. Following the reassessment, a decision should be made to either fully support and promote the actions needed to complete AVLIS development or discontinue support for the program entirely. Management's position is that the Department will successfully complete the AVLIS technology demonstration and that the program should continue until it can be transferred to a Government corporation. Although the auditors recognize that AVLIS may be transferred, there are enough technical and financial uncertainties that a thorough assessment is warranted.

  20. The sticking of atomic hydrogen on amorphous water ice

    SciTech Connect (OSTI)

    Veeraghattam, Vijay K.; Manrodt, Katie; Lewis, Steven P.; Stancil, P. C. E-mail: lewis@physast.uga.edu

    2014-07-20

    Using classical molecular dynamics, we have simulated the sticking and scattering process of a hydrogen atom on an amorphous ice film to predict the sticking probability of hydrogen on ice surfaces. A wide range of initial kinetic energies of the incident hydrogen atom (10 K-600 K) and two different ice temperatures (10 K and 70 K) were used to investigate this fundamental process in interstellar chemistry. We report here the sticking probability of atomic hydrogen as a function of incident kinetic energy, gas temperature, and substrate temperature, which can be used in astrophysical models. The current results are compared to previous theoretical and experimental studies that have reported a wide range in the sticking coefficient.

  1. Multiphoton- and simultaneous conjugate Ramsey-Borde atom interferometers

    SciTech Connect (OSTI)

    Mueller, Holger; Chiow, Sheng-wey; Herrmann, Sven [Physics Department, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305 (United States); Chu, Steven [Physics Department, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305 (United States); Lawrence Berkeley National Laboratory and Department of Physics, University of California, Berkeley, 1 Cyclotron Road, Berkeley, CA 94720 (United States)

    2008-03-06

    We report on our experiment to measure h/M, the ratio of the Planck constant to the mass of Cs atoms, and thereby the fine-structure constant. The target accuracy is 1 part per billion or better. We focus on two recent milestones: (i) The first realization of atom interferometers based on light-pulse beam splitters that transfer the momentum of up to 12 photon pairs, which increases the useful signal (matter wave phase shift) by a factor of 144 compared to the beam splitters used in the best present atom interferometers. Moreover, they lead to a cancellation of important systematic effects. (ii) The first realization of a simultaneous pair of conjugate Ramsey-Borde interferometers. In these, the relative sign of the inertial term is reversed so that it can be cancelled. Simultaneous operation means that this holds for a time-dependent inertial term (vibrations) too, which promises a substantial improvement in the signal to noise ratio.

  2. Single atom impurity in a single molecular transistor

    SciTech Connect (OSTI)

    Ray, S. J.

    2014-10-21

    The influence of an impurity atom on the electrostatic behaviour of a Single Molecular Transistor was investigated through Ab-initio calculations in a double-gated geometry. The charge stability diagram carries unique signature of the position of the impurity atom in such devices which together with the charging energy of the molecule could be utilised as an electronic fingerprint for the detection of such impurity states in a nano-electronic device. The two gated geometry allows additional control over the electrostatics as can be seen from the total energy surfaces (for a specific charge state), which is sensitive to the positions of the impurity. These devices which are operational at room temperature can provide significant advantages over the conventional silicon based single dopant devices functional at low temperature. The present approach could be a very powerful tool for the detection and control of individual impurity atoms in a single molecular device and for applications in future molecular electronics.

  3. SLAC All Access: Atomic, Molecular and Optical Science Instrument

    ScienceCinema (OSTI)

    Bozek, John

    2014-06-03

    John Bozek, a staff scientist at SLAC's Linac Coherent Light Source (LCLS) X-ray laser who manages the LCLS Soft X-ray Department, takes us behind the scenes at the Atomic, Molecular and Optical Science (AMO) instrument, the first of six experimental stations now operating at LCLS. Samples used in AMO experiments include atoms, molecules, clusters, and nanoscale objects such as protein crystals or viruses. Science performed at AMO includes fundamental studies of light-matter interactions in the extreme X-ray intensity of the LCLS pules, time-resolved studies of increasingly charged states of atoms and molecules, X-ray diffraction imaging of nanocrystals, and single-shot imaging of a variety of objects.

  4. Atomic and electronic structure of Ni-Nb metallic glasses

    SciTech Connect (OSTI)

    Yuan, C. C.; Yang, Y.-F. Xi, X. K.

    2013-12-07

    Solid state {sup 93}Nb nuclear magnetic resonance spectroscopy has been employed to investigate the atomic and electronic structures in Ni-Nb based metallic glass (MG) model system. {sup 93}Nb nuclear magnetic resonance (NMR) isotropic metallic shift of Ni{sub 60}Nb{sub 35}Sn{sub 5} has been found to be ∼100 ppm lower than that of Ni{sub 60}Nb{sub 35}Zr{sub 5} MG, which is correlated with their intrinsic fracture toughness. The evolution of {sup 93}Nb NMR isotropic metallic shifts upon alloying is clearly an electronic origin, as revealed by both local hyperfine fields analysis and first-principle computations. This preliminary result indicates that, in addition to geometrical considerations, atomic form factors should be taken into a description of atomic structures for better understanding the mechanical behaviors of MGs.

  5. Big Bang Day : The Great Big Particle Adventure - 1. Atom

    ScienceCinema (OSTI)

    None

    2011-04-25

    In this series, comedian and physicist Ben Miller asks the CERN scientists what they hope to find. The notion of atoms dates back to Greek philosophers who sought a natural mechanical explanation of the Universe, as opposed to a divine one. The existence what we call chemical atoms, the constituents of all we see around us, wasn't proved until a hundred years ago, but almost simultaneously it was realised these weren't the indivisible constituents the Greeks envisaged. Much of the story of physics since then has been the ever-deeper probing of matter until, at the end of the 20th century, a complete list of fundamental ingredients had been identified, apart from one, the much discussed Higgs particle. In this programme, Ben finds out why this last particle is so pivotal, not just to atomic theory, but to our very existence - and how hopeful the scientists are of proving its existence.

  6. Directing Matter: Toward Atomic-Scale 3D Nanofabrication

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

    Jesse, Stephen; Borisevich, Albina Y.; Fowlkes, Jason D.; Lupini, Andrew R.; Rack, Philip D.; Unocic, Raymond R.; Sumpter, Bobby G.; Kalinin, Sergei V.; Belianinov, Alex; Ovchinnikova, Olga S.

    2016-05-16

    Here we report that enabling memristive, neuromorphic, and quantum based computing as well as efficient mainstream energy storage and conversion technologies requires next generation of materials customized at the atomic scale. This requires full control of atomic arrangement and bonding in three dimensions. The last two decades witnessed substantial industrial, academic, and government research efforts directed towards this goal through various lithographies and scanning probe based methods. These technologies emphasize 2D surface structures, with some limited 3D capability. Recently, a range of focused electron and ion based methods have demonstrated compelling alternative pathways to achieving atomically precise manufacturing of 3Dmore » structures in solids, liquids, and at interfaces. Electron and ion microscopies offer a platform that can simultaneously observe dynamic and static structures at the nano and atomic scales, and also induce structural rearrangements and chemical transformation. The addition of predictive modeling or rapid image analytics and feedback enables guiding these in a controlled manner. Here, we review the recent results that used focused electron and ion beams to create free-standing nanoscale 3D structures, radiolysis and the fabrication potential with liquid precursors, epitaxial crystallization of amorphous oxides with atomic layer precision, as well as visualization and control of individual dopant motion within a 3D crystal lattice. These works lay the foundation for new approaches to directing nanoscale level architectures and offer a potential roadmap to full 3D atomic control in materials. Lastly, in this perspective we lay out the gaps that currently constrain the processing range of these platforms, reflect on indirect requirements, such as the integration of large scale data analysis with theory, and discuss future prospects of these technologies.« less

  7. High-accuracy coupled cluster calculations of atomic properties

    SciTech Connect (OSTI)

    Borschevsky, A.; Yakobi, H.; Eliav, E.; Kaldor, U.

    2015-01-22

    The four-component Fock-space coupled cluster and intermediate Hamiltonian methods are implemented to evaluate atomic properties. The latter include the spectra of nobelium and lawrencium (elements 102 and 103) in the range 20000-30000 cm{sup −1}, the polarizabilities of elements 112-114 and 118, required for estimating their adsorption enthalpies on surfaces used to separate them in accelerators, and the nuclear quadrupole moments of some heavy atoms. The calculations on superheavy elements are supported by the very good agreement with experiment obtained for the lighter homologues.

  8. Atomic vapor laser isotope separation using resonance ionization

    SciTech Connect (OSTI)

    Comaskey, B.; Crane, J.; Erbert, G.; Haynam, C.; Johnson, M.; Morris, J.; Paisner, J.; Solarz, R.; Worden, E.

    1986-09-01

    Atomic vapor laser isotope separation (AVLIS) is a general and powerful technique. A major present application to the enrichment of uranium for light-water power-reactor fuel has been under development for over 10 years. In June 1985, the Department of Energy announced the selection of AVLIS as the technology to meet the nation's future need for enriched uranium. Resonance photoionization is the heart of the AVLIS process. We discuss those fundamental atomic parameters that are necessary for describing isotope-selective resonant multistep photoionization along with the measurement techniques that we use. We illustrate the methodology adopted with examples of other elements that are under study in our program.

  9. Bettis and Knolls Atomic Power Laboratories | National Nuclear Security

    National Nuclear Security Administration (NNSA)

    Administration | (NNSA) Bettis and Knolls Atomic Power Laboratories Bettis and Knolls Atomic Power Laboratories DE-NR0000031 Managed and Operated by Bechtel Marine Propulsion Corporation Updated to Modification 075 dated 10/10/2012 BASIC Contract (Official) Modifications (Official) Funding Mods Available Upon Request Conformed Contract (Unofficial) Basic Contract (9/18/2008) (pdf, 2307KB) NR 001 (12/8/08) (pdf, 7938KB) DE-NR0000031 (Conformed to Mod 075 dated 10/10/2011) (pdf, 12MB) NR 002

  10. Paying tribute to our atomic veterans | National Nuclear Security

    National Nuclear Security Administration (NNSA)

    Administration | (NNSA) Paying tribute to our atomic veterans Friday, October 30, 2015 - 3:31pm NNSA Blog Glenn Podonsky, director of the U.S. Department of Energy's Office of Enterprise Assessment, pays tribute to the atomic veterans who worked at the Nevada National Security Site and other sites across the enterprise during the Cold War. He also introduced the video tribute below from Energy Secretary Ernest Moniz as part of the National Day of Remembrance celebration October 30th at the

  11. Berkeley Lab Scientists Grow Atomically Thin Transistors and Circuits |

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

    Department of Energy Berkeley Lab Scientists Grow Atomically Thin Transistors and Circuits Berkeley Lab Scientists Grow Atomically Thin Transistors and Circuits July 12, 2016 - 10:29am Addthis This schematic shows the chemical assembly of two-dimensional crystals. Graphene is first etched into channels and the TMDC molybdenum disulfide (MoS2) begins to nucleate around the edges and within the channel. On the edges, MoS2 slightly overlaps on top of the graphene. Finally, further growth

  12. PPPL and General Atomics scientists make breakthrough in understanding how

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

    to control intense heat bursts in fusion experiments | Princeton Plasma Physics Lab and General Atomics scientists make breakthrough in understanding how to control intense heat bursts in fusion experiments By Raphael Rosen March 13, 2015 Tweet Widget Google Plus One Share on Facebook Carlos Paz-Soldan, left, and Raffi Nazikian at the DIII-D tokamak. (Photo by Lisa Petrillo/General Atomics) Carlos Paz-Soldan, left, and Raffi Nazikian at the DIII-D tokamak. Gallery: Computer simulation of a

  13. PPPL and General Atomics scientists make breakthrough in understanding how

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

    to control intense heat bursts in fusion experiments | Princeton Plasma Physics Lab PPPL and General Atomics scientists make breakthrough in understanding how to control intense heat bursts in fusion experiments By Raphael Rosen March 16, 2015 Tweet Widget Google Plus One Share on Facebook Carlos Paz-Soldan, left, and Raffi Nazikian at the DIII-D tokamak. (Photo by Lisa Petrillo/General Atomics) Carlos Paz-Soldan, left, and Raffi Nazikian at the DIII-D tokamak. Gallery: Computer simulation

  14. An Atomic-Level Understanding of Copper-Based Catalysts

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

    An Atomic-Level Understanding of Copper-Based Catalysts An Atomic-Level Understanding of Copper-Based Catalysts Print Thursday, 05 May 2016 12:20 Copper-based catalysts are widely used in chemical industries to convert water and carbon monoxide to hydrogen, carbon dioxide, and methanol. There are theoretical models used to explain this reaction, but a complete understanding of the process has been lacking. However, recent research at the ALS has shed light on the process, giving scientists key

  15. Reinventing atomic magnetic simulations with spin-orbit coupling

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

    Perera, Meewanage Dilina N.; Eisenbach, Markus; Nicholson, Don M.; Stocks, George Malcolm; Landau, David P.

    2016-02-10

    We propose a powerful extension to the combined molecular and spin dynamics method that fully captures the coupling between the atomic and spin subsystems via spin-orbit interactions. Moreover, the foundation of this method lies in the inclusion of the local magnetic anisotropies that arise as a consequence of the lattice symmetry breaking due to phonons or crystallographic defects. By using canonical simulations of bcc iron with the system coupled to a phonon heat bath, we show that our extension enables the previously unachievable angular momentum exchange between the atomic and spin degrees of freedom.

  16. Laser stripping of hydrogen atoms by direct ionization

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

    Brunetti, E.; Becker, W.; Bryant, H. C.; Jaroszynski, D. A.; Chou, W.

    2015-05-08

    Direct ionization of hydrogen atoms by laser irradiation is investigated as a potential new scheme to generate proton beams without stripping foils. The time-dependent Schrödinger equation describing the atom-radiation interaction is numerically solved obtaining accurate ionization cross-sections for a broad range of laser wavelengths, durations and energies. Parameters are identified where the Doppler frequency up-shift of radiation colliding with relativistic particles can lead to efficient ionization over large volumes and broad bandwidths using currently available lasers.

  17. Phase contrast and operation regimes in multifrequency atomic force microscopy

    SciTech Connect (OSTI)

    Santos, Sergio

    2014-04-07

    In amplitude modulation atomic force microscopy the attractive and the repulsive force regimes induce phase shifts above and below 90°, respectively. In the more recent multifrequency approach, however, multiple operation regimes have been reported and the theory should be revisited. Here, a theory of phase contrast in multifrequency atomic force microscopy is developed and discussed in terms of energy transfer between modes, energy dissipation and the kinetic energy and energy transfer associated with externally driven harmonics. The single frequency virial that controls the phase shift might undergo transitions in sign while the average force (modal virial) remains positive (negative)

  18. How Are Atoms Held Together? | GE Global Research

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

    Are Atoms Held Together? Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new window) Click to share (Opens in new window) Click to share on LinkedIn (Opens in new window) Click to share on Tumblr (Opens in new window) How Are Atoms Held Together? 2012.03.30 Chief Scientist Jim Bray discusses positive and negative charges and their role in keeping matter stable. 0 Comments Comment Name Email Submit Comment You Might Also Like Vin_Smentlowski_AVS_Registration AVS

  19. DOE Comments - Radiation Protection (Atomic Energy Act) | Department of

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

    Energy - Radiation Protection (Atomic Energy Act) DOE Comments - Radiation Protection (Atomic Energy Act) 1. United States Department of Energy Comments on "Application of Protective Action Guides (PAGs) for Radiological Dispersal Devices (RDD) and Improvised Nuclear Device (IND) Incidents"; Notice (71 FR 174; January 3, 2006) (138.29 KB) 2. Department of Energy Comments on NCRP SC 64-23 Draft Report (241.23 KB) 3. DOE Comments on: "Uniform Federal Policy for Quality Assurance

  20. The chip-scale atomic clock : prototype evaluation.

    SciTech Connect (OSTI)

    Mescher, Mark; Varghese, Mathew; Lutwak, Robert; Serkland, Darwin Keith; Tepolt, Gary; Geib, Kent Martin; Leblanc, John; Peake, Gregory Merwin; Rashid, Ahmed

    2007-12-01

    The authors have developed a chip-scale atomic clock (CSAC) for applications requiring atomic timing accuracy in portable battery-powered applications. At PTTI/FCS 2005, they reported on the demonstration of a prototype CSAC, with an overall size of 10 cm{sup 3}, power consumption > 150 mW, and short-term stability sy(t) < 1 x 10-9t-1/2. Since that report, they have completed the development of the CSAC, including provision for autonomous lock acquisition and a calibrated output at 10.0 MHz, in addition to modifications to the physics package and system architecture to improve performance and manufacturability.

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

    SciTech Connect (OSTI)

    Miake, Yudai; Mukaiyama, Takashi; O’Hara, Kenneth M.; Gensemer, Stephen

    2015-04-15

    We have constructed a solid-state light source for experiments with laser cooled lithium atoms based on a Nd:Y V O{sub 4} ring laser with second-harmonic generation. Unidirectional lasing, an improved mode selection, and a high output power of the ring laser were 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 piezoelectric transducers (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.

  2. Bell's Inequality and Universal Quantum Gates in a Cold-Atom Chiral Fermionic p-Wave Superfluid

    SciTech Connect (OSTI)

    Zhang Chuanwei; Tewari, Sumanta; Das Sarma, S.

    2007-11-30

    We propose and analyze a probabilistic scheme to entangle two spatially separated topological qubits in a p{sub x}+ip{sub y} superfluid using controlled collisions between atoms in movable dipole traps and unpaired atoms inside vortex cores in the superfluid. We discuss how to test the violation of Bell's inequality with the generated entanglement. A set of universal quantum gates is shown to be implementable deterministically using the entanglement despite the fact that the entangled states can be created only probabilistically.

  3. Multiple dark-bright solitons in atomic Bose-Einstein condensates

    SciTech Connect (OSTI)

    Yan, D.; Kevrekidis, P. G.; Chang, J. J.; Hamner, C.; Engels, P.; Achilleos, V.; Frantzeskakis, D. J.; Carretero-Gonzalez, R.; Schmelcher, P.

    2011-11-15

    Motivated by recent experimental results, we present a systematic theoretical analysis of dark-bright-soliton interactions and multiple-dark-bright-soliton complexes in atomic two-component Bose-Einstein condensates. We study analytically the interactions between two dark-bright solitons in a homogeneous condensate and then extend our considerations to the presence of the trap. We illustrate the existence of robust stationary dark-bright-soliton ''molecules,'' composed of two or more solitons, which are formed due to the competition of the interaction forces between the dark- and bright-soliton components and the trap force. Our analysis is based on an effective equation of motion, derived for the distance between two dark-bright solitons. This equation provides equilibrium positions and characteristic oscillation frequencies of the solitons, which are found to be in good agreement with the eigenfrequencies of the anomalous modes of the system.

  4. Atomic-scale electrochemistry on the surface of a manganite

    SciTech Connect (OSTI)

    Vasudevan, Rama K; Tselev, Alexander; Baddorf, Arthur P; Kalinin, Sergei V

    2015-01-01

    The doped manganese oxides (manganites) have been widely studied for their colossal magnetoresistive effects, for potential applications in oxide spintronics, electroforming in resistive switching devices, and are materials of choice as cathodes in modern solid oxide fuel cells. However, little experimental knowledge of the dynamics of the surfaces of perovskite manganites at the atomic scale exists. Here, through in-situ scanning tunnelling microscopy (STM), we demonstrate atomic resolution on samples of La0.625Ca0.375MnO3 grown on (001) SrTiO3 by pulsed laser deposition (PLD). Furthermore, by applying triangular DC waveforms of increasing amplitude to the STM tip, and measuring the tunnelling current, we demonstrate the ability to both perform and monitor surface electrochemical processes at the atomic level, including, for the first time in a manganite, formation of single and multiple oxygen vacancies, disruption of the overlying manganite layers, and removal and deposition of individual atomic units or clusters. Our work paves the way for better understanding of surface oxygen reactions in these systems.

  5. Atomic-scale electrochemistry on the surface of a manganite

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

    Vasudevan, Rama K; Tselev, Alexander; Baddorf, Arthur P; Kalinin, Sergei V

    2015-01-01

    The doped manganese oxides (manganites) have been widely studied for their colossal magnetoresistive effects, for potential applications in oxide spintronics, electroforming in resistive switching devices, and are materials of choice as cathodes in modern solid oxide fuel cells. However, little experimental knowledge of the dynamics of the surfaces of perovskite manganites at the atomic scale exists. Here, through in-situ scanning tunnelling microscopy (STM), we demonstrate atomic resolution on samples of La0.625Ca0.375MnO3 grown on (001) SrTiO3 by pulsed laser deposition (PLD). Furthermore, by applying triangular DC waveforms of increasing amplitude to the STM tip, and measuring the tunnelling current, we demonstratemore » the ability to both perform and monitor surface electrochemical processes at the atomic level, including, for the first time in a manganite, formation of single and multiple oxygen vacancies, disruption of the overlying manganite layers, and removal and deposition of individual atomic units or clusters. Our work paves the way for better understanding of surface oxygen reactions in these systems.« less

  6. Argonne Outloud promo: From Atoms to Advanced Energy Technologies | Argonne

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

    National Laboratory promo: From Atoms to Advanced Energy Technologies Share Browse By - Any - General Argonne Information Energy -Energy efficiency --Vehicles ---Alternative fuels ---Automotive engineering ---Diesel ---Electric drive technology ---Hybrid & electric vehicles ---Hydrogen & fuel cells ---Internal combustion ---Powertrain research --Building design ---Construction --Manufacturing -Energy sources --Renewable energy ---Bioenergy ---Solar energy --Fossil fuels ---Natural

  7. NOx reduction by electron beam-produced nitrogen atom injection

    DOE Patents [OSTI]

    Penetrante, Bernardino M.

    2002-01-01

    Deactivated atomic nitrogen generated by an electron beam from a gas stream containing more than 99% N.sub.2 is injected at low temperatures into an engine exhaust to reduce NOx emissions. High NOx reduction efficiency is achieved with compact electron beam devices without use of a catalyst.

  8. Development of Highly Selective Oxidation Catalysts by Atomic Layer Deposition

    Broader source: Energy.gov [DOE]

    This factsheet describes a research project whose goal is to use Atomic Layer Deposition to construct nanostructured catalysts to improve the effectiveness of oxidative dehydrogenation of alkanes. More effective catalysts could enable higher specific conversion rates and result in drastic energy savings - up to 25 trillion Btu per year by 2020.

  9. Safeguards Agreement and Protocol with the International Atomic Energy Agency

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

    2004-01-07

    To ensure that DOE complies with the Agreement Between the United States of America and the International Atomic Energy Agency for the Application of Safeguards in the United States, the Protocol to the Agreement, and the subsidiary arrangements to the Agreement. Canceled by DOE O 142.2A. Cancels DOE 1270.2B.

  10. Surface determination through atomically resolved secondary-electron imaging

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

    Ciston, J.; Brown, H. G.; D’Alfonso, A. J.; Koirala, P.; Ophus, C.; Lin, Y.; Suzuki, Y.; Inada, H.; Zhu, Y.; Allen, L. J.; et al

    2015-06-17

    We report that unique determination of the atomic structure of technologically relevant surfaces is often limited by both a need for homogeneous crystals and ambiguity of registration between the surface and bulk. Atomically resolved secondary-electron imaging is extremely sensitive to this registration and is compatible with faceted nanomaterials, but has not been previously utilized for surface structure determination. Here we show a detailed experimental atomic-resolution secondary-electron microscopy analysis of the c(6 x 2) reconstruction on strontium titanate (001) coupled with careful simulation of secondary-electron images, density functional theory calculations and surface monolayer-sensitive aberration-corrected plan-view high-resolution transmission electron microscopy. Our workmore » reveals several unexpected findings, including an amended registry of the surface on the bulk and strontium atoms with unusual seven-fold coordination within a typically high surface coverage of square pyramidal TiO5 units. Lastly, dielectric screening is found to play a critical role in attenuating secondary-electron generation processes from valence orbitals.« less

  11. Robust quantum logic in neutral atoms via adiabatic Rydberg dressing

    SciTech Connect (OSTI)

    Keating, Tyler; Cook, Robert L.; Hankin, Aaron M.; Jau, Yuan -Yu; Biedermann, Grant W.; Deutsch, Ivan H.

    2015-01-28

    We study a scheme for implementing a controlled-Z (CZ) gate between two neutral-atom qubits based on the Rydberg blockade mechanism in a manner that is robust to errors caused by atomic motion. By employing adiabatic dressing of the ground electronic state, we can protect the gate from decoherence due to random phase errors that typically arise because of atomic thermal motion. In addition, the adiabatic protocol allows for a Doppler-free configuration that involves counterpropagating lasers in a ?+/?- orthogonal polarization geometry that further reduces motional errors due to Doppler shifts. The residual motional error is dominated by dipole-dipole forces acting on doubly-excited Rydberg atoms when the blockade is imperfect. As a result, for reasonable parameters, with qubits encoded into the clock states of 133Cs, we predict that our protocol could produce a CZ gate in < 10 ?s with error probability on the order of 10-3.

  12. The Common Elements of Atomic and Hadronic Physics

    SciTech Connect (OSTI)

    Brodsky, Stanley J.

    2015-02-26

    Atomic physics and hadronic physics are both governed by the Yang Mills gauge theory Lagrangian; in fact, Abelian quantum electrodynamics can be regarded as the zero-color limit of quantum chromodynamics. I review a number of areas where the techniques of atomic physics can provide important insight into hadronic eigenstates in QCD. For example, the Dirac-Coulomb equation, which predicts the spectroscopy and structure of hydrogenic atoms, has an analog in hadron physics in the form of frame-independent light-front relativistic equations of motion consistent with light-front holography which give a remarkable first approximation to the spectroscopy, dynamics, and structure of light hadrons. The production of antihydrogen in flight can provide important insight into the dynamics of hadron production in QCD at the amplitude level. The renormalization scale for the running coupling is unambiguously set in QED; an analogous procedure sets the renormalization scales in QCD, leading to scheme-independent scale-fixed predictions. Conversely, many techniques which have been developed for hadron physics, such as scaling laws, evolution equations, the quark-interchange process and light-front quantization have important applicants for atomic physics and photon science, especially in the relativistic domain.

  13. Robust quantum logic in neutral atoms via adiabatic Rydberg dressing

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

    Keating, Tyler; Cook, Robert L.; Hankin, Aaron M.; Jau, Yuan -Yu; Biedermann, Grant W.; Deutsch, Ivan H.

    2015-01-28

    We study a scheme for implementing a controlled-Z (CZ) gate between two neutral-atom qubits based on the Rydberg blockade mechanism in a manner that is robust to errors caused by atomic motion. By employing adiabatic dressing of the ground electronic state, we can protect the gate from decoherence due to random phase errors that typically arise because of atomic thermal motion. In addition, the adiabatic protocol allows for a Doppler-free configuration that involves counterpropagating lasers in a σ+/σ- orthogonal polarization geometry that further reduces motional errors due to Doppler shifts. The residual motional error is dominated by dipole-dipole forces actingmore » on doubly-excited Rydberg atoms when the blockade is imperfect. As a result, for reasonable parameters, with qubits encoded into the clock states of 133Cs, we predict that our protocol could produce a CZ gate in < 10 μs with error probability on the order of 10-3.« less

  14. Translation and integration of numerical atomic orbitals in linear molecules

    SciTech Connect (OSTI)

    Heinäsmäki, Sami

    2014-02-14

    We present algorithms for translation and integration of atomic orbitals for LCAO calculations in linear molecules. The method applies to arbitrary radial functions given on a numerical mesh. The algorithms are based on pseudospectral differentiation matrices in two dimensions and the corresponding two-dimensional Gaussian quadratures. As a result, multicenter overlap and Coulomb integrals can be evaluated effectively.

  15. Atom interferometry in space: Thermal management and magnetic shielding

    SciTech Connect (OSTI)

    Milke, Alexander; Kubelka-Lange, André; Gürlebeck, Norman Rievers, Benny; Herrmann, Sven; Schuldt, Thilo; Braxmaier, Claus

    2014-08-15

    Atom interferometry is an exciting tool to probe fundamental physics. It is considered especially apt to test the universality of free fall by using two different sorts of atoms. The increasing sensitivity required for this kind of experiment sets severe requirements on its environments, instrument control, and systematic effects. This can partially be mitigated by going to space as was proposed, for example, in the Spacetime Explorer and Quantum Equivalence Principle Space Test (STE-QUEST) mission. However, the requirements on the instrument are still very challenging. For example, the specifications of the STE-QUEST mission imply that the Feshbach coils of the atom interferometer are allowed to change their radius only by about 260 nm or 2.6 × 10{sup −4} % due to thermal expansion although they consume an average power of 22 W. Also Earth's magnetic field has to be suppressed by a factor of 10{sup 5}. We show in this article that with the right design such thermal and magnetic requirements can indeed be met and that these are not an impediment for the exciting physics possible with atom interferometers in space.

  16. Atomic radii for atoms with the 6s shell outermost: The effective atomic radius and the van der Waals radius from {sub 55}Cs to {sub 80}Hg

    SciTech Connect (OSTI)

    Tatewaki, Hiroshi; Hatano, Yasuyo; Noro, Takeshi; Yamamoto, Shigeyoshi

    2015-06-15

    We consider, for atoms from {sub 55}Cs to {sub 80}Hg, the effective atomic radius (r{sub ear}), which is defined as the distance from the nucleus at which the magnitude of the electric field is equal to that in He at one half of the equilibrium bond length of He{sub 2}. The values of r{sub ear} are about 50% larger than the mean radius of the outermost occupied orbital of 6s, . The value of r{sub ear} decreases from {sub 55}Cs to {sub 56}Ba and undergoes increases and decreases with rising nuclear charge from {sub 57}La to {sub 70}Y b. In fact r{sub ear} is understood as comprising two interlaced sequences; one consists of {sub 57}La, {sub 58}Ce, and {sub 64}Gd, which have electronic configuration (4f{sup n−1})(5d{sup 1})(6s{sup 2}), and the remaining atoms have configuration (4f{sup n})(6s{sup 2}). The sphere defined by r{sub ear} contains 85%–90% of the 6s electrons. From {sub 71}Lu to {sub 80}Hg the radius r{sub ear} also involves two sequences, corresponding to the two configurations 5d{sup n+1}6s{sup 1} and 5d{sup n}6s{sup 2}. The radius r{sub ear} according to the present methodology is considerably larger than r{sub vdW} obtained by other investigators, some of who have found values of r{sub vdW} close to .

  17. Hewlett and Holl - Atoms for Peace and War | Department of Energy

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

    Holl - Atoms for Peace and War Hewlett and Holl - Atoms for Peace and War Richard G. Hewlett and Jack M. Holl. Atoms for Peace and War: The Eisenhower Administration and the Atomic Energy Commission. A History of the Atomic Energy Commission, Volume III. Text in each PDF is fully searchable. HewlettandHollAtomsforPeaceandWarComplete.pdf (9.01 MB) HewlettandHollAtomsforPeaceandWarPicturesOnly.pdf (6.66 MB) More Documents & Publications A History of the Atomic Energy Commission Hewlett and

  18. Unconventional states and geometric effects in mesoscopic systems of ultra-cold atomic Fermi gases

    SciTech Connect (OSTI)

    Bolech, C. J.

    2014-10-15

    During the last decade, experiments all over the world started to test the superconducting state of matter using a newly developed mesoscopic tunable system: trapped ultra-cold atomic gases. Theorists and experimentalists hand-in-hand are now able to advance our understanding of the superconducting state by asking new questions that probe further into the physical mechanisms underlying the phenomenon and the door is open to the exploration of exotic unconventional superconducting states. In particular, a series of experiments on systems of trapped cold atomic gases were aimed at studying the effects of polarization on superconducting pairing. Two different experimental groups encountered surprising qualitative and quantitative discrepancies which seemed to be a function of the confining geometry and the cooling protocol. Our numerical studies demonstrate a tendency towards metastability and suggest an explanation for the observed discrepancy. From our calculations, the most likely solution which is consistent with the experiments supports a state strikingly similar to the so called FFLO state (after Ferrell, Fulde, Larkin and Ovchinnikov), which had been theorized long ago but eluded detection so far. Moreover, the three-dimensional scenario described above is reminiscent of predictions for one-dimensional systems of dilute polarized attractive gases and another set of ultra-cold-atom experiments incorporates optical lattices to study this reduced-dimensionality setting. The measurements are in quantitative agreement with theoretical calculations (using a wide array of numerical and analytic techniques) in which a partially polarized phase is found to be the one-dimensional analogue of the FFLO state. Moreover, exploring the dimensional-crossover regime, our latest findings indicate that the mesoscopic nature of these quasi-one-dimensional systems favors the appearance of a new type of Mott phase transition involving an emergent pair-superfluid of equal

  19. 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@gmail.com; Xiao, Shifang; Li, Xiaofan; Hu, Wangyu; Ao, Bingyun; Chen, Piheng

    2014-04-28

    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.

  20. Carbon nanotube forests growth using catalysts from atomic layer deposition

    SciTech Connect (OSTI)

    Chen, Bingan; Zhang, Can; Esconjauregui, Santiago; Xie, Rongsi; Zhong, Guofang; Robertson, John; Bhardwaj, Sunil; Cepek, Cinzia

    2014-04-14

    We have grown carbon nanotubes using Fe and Ni catalyst films deposited by atomic layer deposition. Both metals lead to catalytically active nanoparticles for growing vertically aligned nanotube forests or carbon fibres, depending on the growth conditions and whether the substrate is alumina or silica. The resulting nanotubes have narrow diameter and wall number distributions that are as narrow as those grown from sputtered catalysts. The state of the catalyst is studied by in-situ and ex-situ X-ray photoemission spectroscopy. We demonstrate multi-directional nanotube growth on a porous alumina foam coated with Fe prepared by atomic layer deposition. This deposition technique can be useful for nanotube applications in microelectronics, filter technology, and energy storage.

  1. Programming new geometry restraints: Parallelity of atomic groups

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

    Sobolev, Oleg V.; Afonine, Pavel V.; Adams, Paul D.; Urzhumtsev, Alexandre

    2015-08-01

    Improvements in structural biology methods, in particular crystallography and cryo-electron microscopy, have created an increased demand for the refinement of atomic models against low-resolution experimental data. One way to compensate for the lack of high-resolution experimental data is to use a priori information about model geometry that can be utilized in refinement in the form of stereochemical restraints or constraints. Here, the definition and calculation of the restraints that can be imposed on planar atomic groups, in particular the angle between such groups, are described. Detailed derivations of the restraint targets and their gradients are provided so that they canmore » be readily implemented in other contexts. Practical implementations of the restraints, and of associated data structures, in the Computational Crystallography Toolbox(cctbx) are presented.« less

  2. Programming new geometry restraints: Parallelity of atomic groups

    SciTech Connect (OSTI)

    Sobolev, Oleg V.; Afonine, Pavel V.; Adams, Paul D.; Urzhumtsev, Alexandre

    2015-08-01

    Improvements in structural biology methods, in particular crystallography and cryo-electron microscopy, have created an increased demand for the refinement of atomic models against low-resolution experimental data. One way to compensate for the lack of high-resolution experimental data is to use a priori information about model geometry that can be utilized in refinement in the form of stereochemical restraints or constraints. Here, the definition and calculation of the restraints that can be imposed on planar atomic groups, in particular the angle between such groups, are described. Detailed derivations of the restraint targets and their gradients are provided so that they can be readily implemented in other contexts. Practical implementations of the restraints, and of associated data structures, in the Computational Crystallography Toolbox(cctbx) are presented.

  3. Quantum entanglement for helium atom in the Debye plasmas

    SciTech Connect (OSTI)

    Lin, Yen-Chang; Fang, Te-Kuei; Ho, Yew Kam

    2015-03-15

    In the present work, we present an investigation on quantum entanglement of the two-electron helium atom immersed in weakly coupled Debye plasmas, modeled by the Debye-Hckel, or screened Coulomb, potential to mimic the interaction between two charged particles inside the plasma. Quantum entanglement is related to correlation effects in a multi-particle system. In a bipartite system, a measurement made on one of the two entangled particles affects the outcome of the other particle, even if such two particles are far apart. Employing wave functions constructed with configuration interaction B-spline basis, we have quantified von Neumann entropy and linear entropy for a series of He {sup 1,3}S{sup e} and {sup 1,3}P{sup o} states in plasma-embedded helium atom.

  4. Atomic picture of elastic deformation in a metallic glass

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

    Wang, X. D.; Aryal, S.; Zhong, C.; Ching, W. Y.; Sheng, H. W.; Zhang, H.; Zhang, D. X.; Cao, Q. P.; Jiang, J. Z.

    2015-03-17

    The tensile behavior of a Ni₆₀Nb₄₀ metallic glass (MG) has been studied by using ab initio density functional theory (DFT) calculation with a large cell containing 1024 atoms (614 Ni and 410 Nb). We provide insight into how a super elastic limit can be achieved in a MG. Spatially inhomogeneous responses of single atoms and also major polyhedra are found to change greatly with increasing external stress when the strain is over 2%, causing the intrinsically viscoelastic behavior. We uncover the origin of the observed super elastic strain limit under tension (including linear and viscoelastic strains) in small-sized MG samples,more » mainly caused by inhomogeneous distribution of excess volumes in the form of newly formed subatomic cavities.« less

  5. Quantum Coherence between Two Atoms beyond Q=10{sup 15}

    SciTech Connect (OSTI)

    Chou, C. W.; Hume, D. B.; Thorpe, M. J.; Wineland, D. J.; Rosenband, T. [Time and Frequency Division, National Institute of Standards and Technology, Boulder, Colorado 80305 (United States)

    2011-04-22

    We place two atoms in quantum superposition states and observe coherent phase evolution for 3.4x10{sup 15} cycles. Correlation signals from the two atoms yield information about their relative phase even after the probe radiation has decohered. This technique allowed a frequency comparison of two {sup 27}Al{sup +} ions with fractional uncertainty 3.7{sub -0.8}{sup +1.0}x10{sup -16}/{radical}({tau}/s). Two measures of the Q factor are reported: The Q factor derived from quantum coherence is 3.4{sub -1.1}{sup +2.4}x10{sup 16}, and the spectroscopic Q factor for a Ramsey time of 3 s is 6.7x10{sup 15}. We demonstrate a method to detect the individual quantum states of two Al{sup +} ions in a Mg{sup +}-Al{sup +}-Al{sup +} linear ion chain without spatially resolving the ions.

  6. Collisional shifts in optical-lattice atom clocks

    SciTech Connect (OSTI)

    Band, Y. B. [Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel); Atomic Physics Division, A267 Physics, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Ilse Katz Center for Nano-Science, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel); Vardi, A. [Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel)

    2006-09-15

    We theoretically study the effects of elastic collisions on the determination of frequency standards via Ramsey-fringe spectroscopy in optical-lattice atom clocks. Interparticle interactions of bosonic atoms in multiply occupied lattice sites can cause a linear frequency shift, as well as generate asymmetric Ramsey-fringe patterns and reduce fringe visibility due to interparticle entanglement. We propose a method of reducing these collisional effects in an optical lattice by introducing a phase difference of {pi} between the Ramsey driving fields in adjacent sites. This configuration suppresses site-to-site hopping due to interference of two tunneling pathways, without degrading fringe visibility. Consequently, the probability of double occupancy is reduced, leading to cancellation of collisional shifts.

  7. Electrohydrodynamic atomization (EHDA) assisted wet chemical synthesis of nickel nanoparticles

    SciTech Connect (OSTI)

    Barzegar Vishlaghi, M. [Department of Mechanical Engineering, University of Tabriz, Tabriz (Iran, Islamic Republic of)] [Department of Mechanical Engineering, University of Tabriz, Tabriz (Iran, Islamic Republic of); Farzalipour Tabriz, M., E-mail: meisam.fa@gmail.com [Department of Mechanical Engineering, University of Tabriz, Tabriz (Iran, Islamic Republic of); Mohammad Moradi, O. [Department of Mechanical Engineering, University of Tabriz, Tabriz (Iran, Islamic Republic of)] [Department of Mechanical Engineering, University of Tabriz, Tabriz (Iran, Islamic Republic of)

    2012-07-15

    Highlights: ? Electrohydrodynamic atomization (EHDA) assisted chemical synthesis of nickel nanoparticles is reported. ? Substituting water with non-aqueous media prevents the formation of nickel hydroxide. ? Size of particles decreased from 10 to 20 nm down to 24 nm by using multi-jet mode. ? Synthesized nanoparticles have diffraction patterns similar to amorphous materials. -- Abstract: In this study nickel nanoparticles were prepared via chemical reduction of nickel acetate using sodium borohydride using electrohydrodynamic atomization (EHDA) technique. This technique was used to spray a finely dispersed aerosol of nickel precursor solution into the reductive bath. Obtained particles were characterized by means of X-ray diffraction (XRD), UVVisible spectroscopy, and transmission electron microscopy (TEM). Results confirmed the formation of nickel nanoparticles and showed that applying EHDA technique to chemical reduction method results in producing smaller particles with narrower size distribution in comparison with conventional reductive precipitation method.

  8. Multimode quantum memory based on atomic frequency combs

    SciTech Connect (OSTI)

    Afzelius, Mikael; Simon, Christoph; Riedmatten, Hugues de; Gisin, Nicolas

    2009-05-15

    An efficient multimode quantum memory is a crucial resource for long-distance quantum communication based on quantum repeaters. We propose a quantum memory based on spectral shaping of an inhomogeneously broadened optical transition into an atomic frequency comb (AFC). The spectral width of the AFC allows efficient storage of multiple temporal modes without the need to increase the absorption depth of the storage material, in contrast to previously known quantum memories. Efficient readout is possible thanks to rephasing of the atomic dipoles due to the AFC structure. Long-time storage and on-demand readout is achieved by use of spin states in a lambda-type configuration. We show that an AFC quantum memory realized in solids doped with rare-earth-metal ions could store hundreds of modes or more with close to unit efficiency, for material parameters achievable today.

  9. Direct visualization of atomically precise nitrogen-doped graphene nanoribbons

    SciTech Connect (OSTI)

    Zhang, Yi; Zhang, Yanfang; Li, Geng; Lu, Jianchen; Du, Shixuan, E-mail: sxdu@iphy.ac.cn, E-mail: feng@mpip-mainz.mpg.de; Gao, Hong-Jun [Institute of Physics and University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190 (China); Lin, Xiao [University of Chinese Academy of Sciences and Institute of Physics, Chinese Academy of Sciences, Beijing 100049 (China); Berger, Reinhard; Feng, Xinliang, E-mail: sxdu@iphy.ac.cn, E-mail: feng@mpip-mainz.mpg.de; Mllen, Klaus [Max Planck Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz (Germany)

    2014-07-14

    We have fabricated atomically precise nitrogen-doped chevron-type graphene nanoribbons by using the on-surface synthesis technique combined with the nitrogen substitution of the precursors. Scanning tunneling microscopy and spectroscopy indicate that the well-defined nanoribbons tend to align with the neighbors side-by-side with a band gap of 1.02?eV, which is in good agreement with the density functional theory calculation result. The influence of the high precursor coverage on the quality of the nanoribbons is also studied. We find that graphene nanoribbons with sufficient aspect ratios can only be fabricated at sub-monolayer precursor coverage. This work provides a way to construct atomically precise nitrogen-doped graphene nanoribbons.

  10. High pressure injection and atomization characteristics of methanol

    SciTech Connect (OSTI)

    Aigal, A.K.; Pundir, B.P.; Khatchian, A.S.

    1986-01-01

    Research on conversion of diesel engines for operation on methanol is, currently, of worldwide interest. Due to requirements of higher cyclic delivery of methanol and changes in fuel properties e.g. compressibility, wave propagation velocity, viscosity, surface tension, density etc., injection and atomization characteristics of methanol are expected to be different from diesel. From the equation of continuity and forces acting on the injection system elements and applying the principles of similarity, modifications required in the injection system were identified. Methanol injection and atomization characteristics were studied with a modified injection system and compared with those observed with diesel fuel. Methanol gave more favourable cyclic delivery characteristics than diesel. Laser diffraction technique was used to study time and space resolved drop size distribution in methanol and diesel sprays. With methanol, drop size distribution were, generally, much narrower and droplets were smaller than diesel. Spatial distribution of drop size in methanol spray showed somewhat different trends than for diesel.

  11. Atomic quantum corrals for Bose-Einstein condensates

    SciTech Connect (OSTI)

    Xiong Hongwei [State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China); Kavli Institute for Theoretical Physics China, Chinese Academy of Sciences, Beijing 100190 (China); Wu Biao [Kavli Institute for Theoretical Physics China, Chinese Academy of Sciences, Beijing 100190 (China); International Center for Quantum Materials, Peking University, Beijing 100871 (China); Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2010-11-15

    We consider the dynamics of Bose-Einstein condensates in a corral-like potential. Compared to the electronic quantum corrals, the atomic quantum corrals have the advantages of allowing direct and convenient observation of the wave dynamics, together with adjustable interaction strength. Our numerical study shows that these advantages not only allow exploration of the rich dynamical structures in the density distribution but also make the corrals useful in many other aspects. In particular, the corrals for atoms can be arranged into a stadium shape for the experimental visualization of quantum chaos, which has been elusive with electronic quantum corrals. The density correlation is used to describe quantitatively the dynamical quantum chaos. Furthermore, we find that the interatomic interaction can greatly enhance the dynamical quantum chaos, for example, inducing a chaotic behavior even in circle-shaped corrals.

  12. Accurate Optical Lattice Clock with {sup 87}Sr Atoms

    SciTech Connect (OSTI)

    Le Targat, Rodolphe; Baillard, Xavier; Fouche, Mathilde; Brusch, Anders; Tcherbakoff, Olivier; Rovera, Giovanni D.; Lemonde, Pierre

    2006-09-29

    We report a frequency measurement of the {sup 1}S{sub 0}-{sup 3}P{sub 0} transition of {sup 87}Sr atoms in an optical lattice clock. The frequency is determined to be 429 228 004 229 879(5) Hz with a fractional uncertainty that is comparable to state-of-the-art optical clocks with neutral atoms in free fall. The two previous measurements of this transition were found to disagree by about 2x10{sup -13}, i.e., almost 4 times the combined error bar and 4 to 5 orders of magnitude larger than the claimed ultimate accuracy of this new type of clocks. Our measurement is in agreement with one of these two values and essentially resolves this discrepancy.

  13. Atomic picture of elastic deformation in a metallic glass

    SciTech Connect (OSTI)

    Wang, X. D.; Aryal, S.; Zhong, C.; Ching, W. Y.; Sheng, H. W.; Zhang, H.; Zhang, D. X.; Cao, Q. P.; Jiang, J. Z.

    2015-03-17

    The tensile behavior of a Ni??Nb?? metallic glass (MG) has been studied by using ab initio density functional theory (DFT) calculation with a large cell containing 1024 atoms (614 Ni and 410 Nb). We provide insight into how a super elastic limit can be achieved in a MG. Spatially inhomogeneous responses of single atoms and also major polyhedra are found to change greatly with increasing external stress when the strain is over 2%, causing the intrinsically viscoelastic behavior. We uncover the origin of the observed super elastic strain limit under tension (including linear and viscoelastic strains) in small-sized MG samples, mainly caused by inhomogeneous distribution of excess volumes in the form of newly formed subatomic cavities.

  14. Multi million-to-Billion Atom Molecular Dynamics Simulations of

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

    Cavitation-Induced Damage on a Silica Slab | Argonne Leadership Computing Facility Multi million-to-Billion Atom Molecular Dynamics Simulations of Cavitation-Induced Damage on a Silica Slab Authors: Shekhar, A., Nomura, K., Rajiv, K., Nakano, A., Vashishta, P Cavitation bubble collapse causes severe damage to materials. For example, cavitation erosion is a major threat to the safety of nuclear power plants. The cavitation bubbles may also be utilized for preventing stress corrosion cracking

  15. Computer simulation of D atoms in a Pd lattice

    SciTech Connect (OSTI)

    Berrondo, M. )

    1991-05-10

    We calculate the equilibrium configurations of a system of deuterium atoms absorbed in palladium. The interaction potential energy is taken as a sum of pair functionals including non-additive effects, which are crucial for this case. We conclude from our calculations that the most probable configuration for the deuterium in the {beta}-phase of PdD involves at least a partial occupation of the tetrahedral sites of the fcc palladium unit cell.

  16. Model based control of dynamic atomic force microscope

    SciTech Connect (OSTI)

    Lee, Chibum; Salapaka, Srinivasa M.

    2015-04-15

    A model-based robust control approach is proposed that significantly improves imaging bandwidth for the dynamic mode atomic force microscopy. A model for cantilever oscillation amplitude and phase dynamics is derived and used for the control design. In particular, the control design is based on a linearized model and robust H{sub ∞} control theory. This design yields a significant improvement when compared to the conventional proportional-integral designs and verified by experiments.

  17. UNITED STATES ATOMIC ENERGY COMMISSION CHICAGO OPERATIONS OFFICE

    Office of Legacy Management (LM)

    $$ ,_, . UNITED STATES ATOMIC ENERGY COMMISSION CHICAGO OPERATIONS OFFICE TELEPHONE 9600 SOUTH CASS AVENUE (312) 739-7711 ARCONNE. ILLINOIS 60439 ^,/" _. i ' > ;.:a c. JAN 17 1975 Martin B. Biles, Director Division of Operational Safety, HQ _ DISPOSAL OF SCRAP COPPER, CYCLOTRON DISMANTLING PROJECT, NUCLEAR RESEARCH CENTER, CARNEGIE-MELLON UNIVERSITY (CMU) Enclosed for your information is a copy of the October 28, 1974, letter from T. Morris (CMD) to J. Krupa (CH) with pages 1-4 and 8-16

  18. International Atomic Energy Agency - General Session | Department of Energy

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

    - General Session International Atomic Energy Agency - General Session September 18, 2006 - 8:53am Addthis Prepared Remarks for Energy Secretary Samuel Bodman Thank you Director General ElBaradei. Congratulations to Mr. Abdul Samad Minty on your election as President of this, the 50th IAEA General Conference. President George W. Bush sends a letter wishing us a productive conference. Let me draw from his message: "My Administration has announced a bold new proposal called the Global Nuclear

  19. Nitrogen Atom Transfer From High Valent Iron Nitrides

    SciTech Connect (OSTI)

    Johnson, Michael D.; Smith, Jeremy M.

    2015-10-14

    This report describes the synthesis and reactions of high valent iron nitrides. Organonitrogen compounds such as aziridines are useful species for organic synthesis, but there are few efficient methods for their synthesis. Using iron nitrides to catalytically access these species may allow for their synthesis in an energy-and atom-efficient manner. We have developed a new ligand framework to achieve these goals as well as providing a method for inducing previously unknown reactivity.

  20. Observing Oxygen Atoms Move during Information Storage in Tantalum Oxide

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

    Memristors | Stanford Synchrotron Radiation Lightsource Observing Oxygen Atoms Move during Information Storage in Tantalum Oxide Memristors Saturday, April 30, 2016 Memristor technology, or resistive random access memory (RRAM), is a frontrunner for next generation computer memory, owing to the promise of long endurance, low power, nanoscale device size and fast operation.1 Memristor devices are typically made of a transition metal oxide sandwiched between two metallic electrodes, and

  1. UNITED STATES ATOMIC ENERGY COMMISSION CHICAGO OPERATIONS OFFICE

    Office of Legacy Management (LM)

    &al IL.6 . . UNITED STATES ATOMIC ENERGY COMMISSION CHICAGO OPERATIONS OFFICE 9800 SOUTH CASS AVENUE ARGONNE, ILLINOIS 60439 ztc.&-jj TELEPHONE (312) 739-7711 NOV I 2 1974 Martin B. Biles, Director Division of Operational Safety, HQ RADIOLOGICAL CONDITION SURVEYS OF REAL PROPERTY Reference: Memorandum, Bauer to Biles, dated g/3/74 Enclosed for your information and use is a copy of the September 25, 1974, letter, Neal (ANL) to Manager (CH), with attachments which contain material

  2. UNITED STATES ATOMIC ENERGY COMMISSION NEVADA OPERATIONS OFFICE

    Office of Legacy Management (LM)

    UNITED STATES ATOMIC ENERGY COMMISSION NEVADA OPERATIONS OFFICE . MASTER .r NVO-152 DECEMBER 1974 Las Vegas, Nevada i, SUMMARY RIEPORT , . I ' i (ENT~ALNEVAD~TESTAREA D'lEMOBILIZATION AND '. !: RESTORATION ACTIVITIES --- -- --.- _.-~., ......~~-- . 1;/ , ",' NVO-152' ~ ~ .. I * , * " I ~I 'I 'I I~ I: I I I' I I. :."S;_~:.., 1'0" ,. <:. .* I DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United

  3. Atomic and molecular layer deposition for surface modification

    SciTech Connect (OSTI)

    Vh-Nissi, Mika; Sievnen, Jenni; Salo, Erkki; Heikkil, Pirjo; Kentt, Eija; Johansson, Leena-Sisko; Koskinen, Jorma T.; Harlin, Ali

    2014-06-01

    Atomic and molecular layer deposition (ALD and MLD, respectively) techniques are based on repeated cycles of gassolid surface reactions. A partial monolayer of atoms or molecules is deposited to the surface during a single deposition cycle, enabling tailored film composition in principle down to molecular resolution on ideal surfaces. Typically ALD/MLD has been used for applications where uniform and pinhole free thin film is a necessity even on 3D surfaces. However, thin even non-uniform atomic and molecular deposited layers can also be used to tailor the surface characteristics of different non-ideal substrates. For example, print quality of inkjet printing on polymer films and penetration of water into porous nonwovens can be adjusted with low-temperature deposited metal oxide. In addition, adhesion of extrusion coated biopolymer to inorganic oxides can be improved with a hybrid layer based on lactic acid. - Graphical abstract: Print quality of a polylactide film surface modified with atomic layer deposition prior to inkjet printing (360 dpi) with an aqueous ink. Number of printed dots illustrated as a function of 0, 5, 15 and 25 deposition cycles of trimethylaluminum and water. - Highlights: ALD/MLD can be used to adjust surface characteristics of films and fiber materials. Hydrophobicity after few deposition cycles of Al{sub 2}O{sub 3} due to e.g. complex formation. Same effect on cellulosic fabrics observed with low temperature deposited TiO{sub 2}. Different film growth and oxidation potential with different precursors. Hybrid layer on inorganic layer can be used to improve adhesion of polymer melt.

  4. Using Atom Interferometry to Search for New Forces

    SciTech Connect (OSTI)

    Wacker, Jay G.; /SLAC

    2009-12-11

    Atom interferometry is a rapidly advancing field and this Letter proposes an experiment based on existing technology that can search for new short distance forces. With current technology it is possible to improve the sensitivity by up to a factor of 10{sup 2} and near-future advances will be able to rewrite the limits for forces with ranges from 100 {micro}m to 1km.

  5. Dynamic processes and polarizability of sodium atom in Debye plasmas

    SciTech Connect (OSTI)

    Qi, Yue-Ying Ning, Li-Na

    2014-03-15

    Dynamic processes including excitation and ionization, and spectrum parameters including the oscillator strengths, dipole polarizabilities from the orbital 3s,3p of sodium atom embedded in weakly coupled plasma are investigated in the entire energy range of a non-relativistic regime. The interaction between the valence electron and the atomic core is simulated by a model potential, and the plasma screening of the Coulomb interaction between charged particles is described by the Debye-Hckel model. The screening of Coulomb interactions reduces the number of bound states, decreases their binding energies, broadens their radial distribution of electron wave functions, and significantly changes the continuum wave functions including the amplitudes and phase-shift. These changes strongly affect the dipole matrix elements between the bound-bound and bound-continuum states, and even the oscillator strengths, the photo-ionization cross sections and the dipole polarizabilities. The plasma screening effect changes the interaction between the valence electron and the atomic core into a short-range potential. The energy behaviors of photo-ionization cross sections are unfolded, for instance, its low-energy behavior (obeying Wigner threshold law), and the appearance of multiple shape and virtual-state resonances when the upper bound states emerge into the continuum. The Combet-Farnoux and Cooper minima in the photo-ionization cross sections are also investigated, and here, the Cooper minima appear not only for the l?l+1 channel but also for l?l?1 one, different from that of hydrogen-like ions in a Debye plasma, which appear only in the l?l+1 channel. The total static electric dipole polarizabilities monotonously and dramatically increase with the plasma screening effect increasing, which are similar to those of hydrogen-like ions and lithium atom. Comparison of calculated results for the oscillator strength, the photo-ionization cross section and polarizability with the results

  6. Katharine Page-Atomic-level insights for better materials

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

    Katharine Page Katharine Page-Atomic-level insights for better materials Page's research supports materials' advances that could have wide-ranging impact, investigating, manipulating and manufacturing nano-particles. March 26, 2014 Katharine Page Katharine Page "Page advises young women to be unafraid of exploring new career options and to always ask questions and learn from others along the way." A Love for Science Impassioned by materials science, Katharine Page told her college

  7. LSU EFRC - Center for Atomic Level Catalyst Design - Project

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

    Wet Chemical Synthesis of Atomically Precise Nanocatalysts space control Challa Kumar David A. Bruce Ulrike Diebold James J Spivey Tabbetha A. Dobbins space control PI names & Affiliations: Challa Kumar - Coordinator(LSU), David Bruce (Clemson University), Ulrike Diebold (TU-Vienna), James J. Spivey (LSU), Tabbetha A. Dobbins (Grambling University). In addition to these Key Personnel, senior investigators at LSU (not directly supported by the Center) have contributed to this project: K.

  8. LSU EFRC - Center for Atomic Level Catalyst Design - Research

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

    Research >> space control Wet Chemical Synthesis of Atomically Precise Nanocatalysts space control Control of Structures on Complex Catalyst Supports space control Electrocatalytic Reduction of CO2 space control Activation of CO on Metal Clusters space control Nano-structured Catalysts for CO Activation space control Modeling and Synthesis of Rare Earth Oxides space control space control Research space control space control The Six Projects that comprise our Center's research efforts have

  9. LSU EFRC - Center for Atomic Level Catalyst Design - Technical Conference

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

    2012 2 space control 2012 Technical Conference: Center for Atomic-level Catalyst Design Oct. 8-10, 2012 LSU Welcomes CALC-D researchers to the Center's 4th Annual Technical Conference. Over 50 investigators from the US and Europe, along with students and post-docs, will exchange information over the 3 days of the conference. The conference will feature technical presentations, tours of LSU's synchrotron facility , and five short courses designed to introduce students to the principles and

  10. Atomic veterans and their families: Responses to radiation exposure

    SciTech Connect (OSTI)

    Murphy, B.C.; Ellis, P.; Greenberg, S. )

    1990-07-01

    In-depth interviews with seven atomic veterans and their families indicated powerful psychological effects on all family members from exposure to low-level ionizing radiation. Four themes emerged: the invalidation of their experiences by government and other authority figures; family concerns about genetic effects on future generations; family members' desire to protect each other from fears of physical consequences; and desire to leave a record of their experiences to help prevent future suffering.

  11. Materials Properties at Internal Interfaces: Fundamental Atomic Issues

    SciTech Connect (OSTI)

    Browning, Nigel

    2014-09-12

    During the course of this research, the microscopy methods were applied to many different systems (see publication list). However, the work can be broadly classified into three main areas: the statistical distribution of grain boundary structures under different doping conditions, the identification of individual dopant atoms in oxide materials, and the evaluation of nucleation and growth processes in liquid and more recently. The main results from each of these efforts will be discussed in the final report.

  12. BEAM TRANSPORT AND STORAGE WITH COLD NEUTRAL ATOMS AND MOLECULES

    SciTech Connect (OSTI)

    Walstrom, Peter L.

    2012-05-15

    A large class of cold neutral atoms and molecules is subject to magnetic field-gradient forces. In the presence of a field, hyperfine atomic states are split into several Zeeman levels. The slopes of these curves vs. field are the effective magnetic moments. By means of optical pumping in a field, Zeeman states of neutral lithium atoms and CaH molecules with effective magnetic moments of nearly {+-} one Bohr magneton can be selected. Particles in Zeeman states for which the energy increases with field are repelled by increasing fields; particles in states for which the energy decreases with field are attracted to increasing fields. For stable magnetic confinement, field-repelled states are required. Neutral-particle velocities in the present study are on the order of tens to hundreds of m/s and the magnetic fields needed for transport and injection are on the order of in the range of 0.01-1T. Many of the general concepts of charged-particle beam transport carry over into neutral particle spin-force optics, but with important differences. In general, the role of bending dipoles in charged particle optics is played by quadrupoles in neutral particle optics; the role of quadrupoles is played by sextupoles. The neutralparticle analog of charge-exchange injection into storage rings is the use of lasers to flip the state of particles from field-seeking to field-repelled. Preliminary tracking results for two neutral atom/molecule storage ring configurations are presented. It was found that orbit instabilities limit the confinment time in a racetrack-shaped ring with discrete magnetic elements with drift spaces between them; stable behavior was observed in a toroidal ring with a continuous sextupole field. An alternative concept using a linear sextupole or octupole channel with solenoids on the ends is presently being considered.

  13. Ultra-sensitive Magnetic Microscopy with an Atomic Magnetometer

    SciTech Connect (OSTI)

    Kim, Young Jin

    2015-08-19

    The PowerPoint presentation focused on research goals, specific information about the atomic magnetometer, response and resolution factors of the SERF magnetometer, FC+AM systems, tests of field transfer and resolution on FC, gradient cancellation, testing of AM performance, ideas for a multi-channel AM, including preliminary sensitivity testing, and a description of a 6 channel DAQ system. A few ideas for future work ended the presentation.

  14. DOE - Office of Legacy Management -- Westinghouse Atomic Power Development

    Office of Legacy Management (LM)

    Plant - PA 04 Power Development Plant - PA 04 FUSRAP Considered Sites Site: WESTINGHOUSE ATOMIC POWER DEVELOPMENT PLANT (PA.04 ) Eliminated from consideration under FUSRAP Designated Name: Not Designated Alternate Name: None Location: East Pittsburgh , Pennsylvania PA.04-1 Evaluation Year: 1985 PA.04-2 Site Operations: Research and development on uranium oxide fuel elements in the 1940s. PA.04-3 PA.04-5 Site Disposition: Eliminated - Radiation levels below criteria PA.04-1 Radioactive

  15. Orientation-Dependent Entanglement Lifetime in a Squeezed Atomic Clock

    SciTech Connect (OSTI)

    Leroux, Ian D.; Schleier-Smith, Monika H.; Vuletic, Vladan

    2010-06-25

    We study experimentally the application of a class of entangled states, squeezed spin states, to the improvement of atomic-clock precision. In the presence of anisotropic noise, the entanglement lifetime is strongly dependent on squeezing orientation. We measure the Allan deviation spectrum of a clock operated with a phase-squeezed input state. For averaging times up to 50 s the squeezed clock achieves a given precision 2.8(3) times faster than a clock operating at the standard quantum limit.

  16. Atomic mix in directly driven inertial confinement implosions

    SciTech Connect (OSTI)

    Wilson, D. C.; Ebey, P. S.; Sangster, T. C.; Shmayda, W. T.; Yu. Glebov, V.; Lerche, R. A.

    2011-11-15

    Directly driven implosions on the Omega laser [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] have measured the presence of atomic mix using D+T neutron yield rates from plastic capsules with and without deuterated layers, and a nearly pure tritium fuel containing 0.7% deuterium. In 15, 19, and 24 {mu}m thick plastic shells, D+T neutron yields increased by factors of 86, 112, and 24 when the 1.2 {mu}m thick inner layer was deuterated. Based on adjusting a fully atomic mix modvfel to fit yield degradation in the un-deuterated capsule and applying it to the capsule with the deuterated layer, atomic mixing accounts for 40-75% of the yield degradation due to mix. For the first time, the time dependence of mixed mass was measured by the ratio of the yield rates from both types of capsules. As expected, the amount of mix grows throughout the D+T burn.

  17. Optimization of some parameters of atomic steam-gas powerplant

    SciTech Connect (OSTI)

    Ratnikov, Y.F.

    1985-10-21

    Determination of optimum parameters of binary-type atomic steam-gas powerplant is a difficult analytical problem in view of the complicated interdependence of parameters, which characterize the reactor, gas-turbine, and steam-turbine parts of the installation. Conclusions include: 1) Determination of optimum parameters of atomic steam-gas installation is recommended to produce with gas consumption = const and heat output of the reactor = var. since best technical-economic indices of installation correspond to this case. 2) With increase in power of atomic steam-gas installation, together with improvement in economic indices, the optimum pressure ratio descends and optimum temperature of feed water increases. 3) Increase in the fuel component leads to a decrease of optimum pressure ratio and to increase in temperature of feed water. 4) Change of cost of reactor plant over wide limits virtually does not have effect on numerical values of optimum parameters being investigated. 5) In all cases optimum pressure ratio is more, and temperature of feed water is less than outer limits, obtained by thermodynamic calculations.

  18. The hydrogen atom in plasmas with an external electric field

    SciTech Connect (OSTI)

    Bahar, M. K.; Soylu, A.

    2014-09-15

    We numerically solve the Schrdinger equation, using a more general exponential cosine screened Coulomb (MGECSC) potential with an electric field, in order to investigate the screening and weak external electric field effects on the hydrogen atom in plasmas. The MGECSC potential is examined for four different cases, corresponding to different screening parameters of the potential and the external electric field. The influences of the different screening parameters and the weak external electric field on the energy eigenvalues are determined by solving the corresponding equations using the asymptotic iteration method (AIM). It is found that the corresponding energy values shift when a weak external electric field is applied to the hydrogen atom in a plasma. This study shows that a more general exponential cosine screened Coulomb potential allows the influence of an applied, weak, external electric field on the hydrogen atom to be investigated in detail, for both Debye and quantum plasmas simultaneously. This suggests that such a potential would be useful in modeling similar effects in other applications of plasma physics, and that AIM is an appropriate method for solving the Schrdinger equation, the solution of which becomes more complex due to the use of the MGECSC potential with an applied external electric field.

  19. Atomic oxygen patterning from a biomedical needle-plasma source

    SciTech Connect (OSTI)

    Kelly, Sen; Turner, Miles M.

    2013-09-28

    A plasma needle is a cold plasma source operating at atmospheric pressure. Such sources interact strongly with living cells, but experimental studies on bacterial samples show that this interaction has a surprising pattern resulting in circular or annular killing structures. This paper presents numerical simulations showing that this pattern occurs because biologically active reactive oxygen and nitrogen species are produced dominantly where effluent from the plasma needle interacts with ambient air. A novel solution strategy is utilised coupling plasma produced neutral (uncharged) reactive species to the gas dynamics solving for steady state profiles at the treated biological surface. Numerical results are compared with experimental reports corroborating evidence for atomic oxygen as a key bactericidal species. Surface losses are considered for interaction of plasma produced reactants with reactive solid and liquid interfaces. Atomic oxygen surface reactions on a reactive solid surface with adsorption probabilities above 0.1 are shown to be limited by the flux of atomic oxygen from the plasma. Interaction of the source with an aqueous surface showed hydrogen peroxide as the dominant species at this interface.

  20. Atomic interactions in precision interferometry using Bose-Einstein condensates

    SciTech Connect (OSTI)

    Jamison, Alan O.; Gupta, Subhadeep; Kutz, J. Nathan

    2011-10-15

    We present theoretical tools for predicting and reducing the effects of atomic interactions in Bose-Einstein condensate (BEC) interferometry experiments. To address mean-field shifts during free propagation, we derive a robust scaling solution that reduces the three-dimensional Gross-Pitaevskii equation to a set of three simple differential equations valid for any interaction strength. To model the other common components of a BEC interferometer--condensate splitting, manipulation, and recombination--we generalize the slowly varying envelope reduction, providing both analytic handles and dramatically improved simulations. Applying these tools to a BEC interferometer to measure the fine structure constant, {alpha}[S. Gupta, K. Dieckmann, Z. Hadzibabic, and D. E. Pritchard, Phys. Rev. Lett. 89, 140401 (2002)], we find agreement with the results of the original experiment and demonstrate that atomic interactions do not preclude measurement to better than part-per-billion accuracy, even for atomic species with relatively large scattering lengths. These tools help make BEC interferometry a viable choice for a broad class of precision measurements.